Ali Emrouznejad, G. R. Amin, M. Ghiyasi, Maria Michali
Data Envelopment Analysis (DEA) is a widely used mathematical programming approach for assessing the efficiency of decision-making units (DMUs) in various sectors. Inverse DEA is a post-DEA sensitivity analysis approach developed initially for solving resource allocation. The main objective of Inverse DEA is to determine the optimal quantity of inputs and/or outputs for each DMU under input and/or output perturbation (s) that would allow them to reach a given efficiency target. Since the early 2000s, Inverse DEA has been extended theoretically and applied successfully in different areas including banking, energy, education, sustainability, and supply chain management. In recent years, research has demonstrated the potential of Inverse DEA for solving novel inverse problems, such as estimating merger gains, minimizing production pollution, optimizing business partnerships, and more. This paper provides a comprehensive survey of the latest theoretical and practical advancements in Inverse DEA, while also highlighting potential areas for future research and development in this field. One such area is exploring the use of heuristic algorithms and optimization techniques in conjunction with Inverse DEA models to address issues of infeasibility and nonlinearity. Moreover, applying Inverse DEA to new sectors such as healthcare, agriculture, and environmental and climate change issues holds great promise for future research. Overall, this paper sets the stage for further advancements in this promising approach.
{"title":"A review of inverse data envelopment analysis: origins, development, and future directions","authors":"Ali Emrouznejad, G. R. Amin, M. Ghiyasi, Maria Michali","doi":"10.1093/imaman/dpad006","DOIUrl":"https://doi.org/10.1093/imaman/dpad006","url":null,"abstract":"\u0000 Data Envelopment Analysis (DEA) is a widely used mathematical programming approach for assessing the efficiency of decision-making units (DMUs) in various sectors. Inverse DEA is a post-DEA sensitivity analysis approach developed initially for solving resource allocation. The main objective of Inverse DEA is to determine the optimal quantity of inputs and/or outputs for each DMU under input and/or output perturbation (s) that would allow them to reach a given efficiency target. Since the early 2000s, Inverse DEA has been extended theoretically and applied successfully in different areas including banking, energy, education, sustainability, and supply chain management. In recent years, research has demonstrated the potential of Inverse DEA for solving novel inverse problems, such as estimating merger gains, minimizing production pollution, optimizing business partnerships, and more. This paper provides a comprehensive survey of the latest theoretical and practical advancements in Inverse DEA, while also highlighting potential areas for future research and development in this field. One such area is exploring the use of heuristic algorithms and optimization techniques in conjunction with Inverse DEA models to address issues of infeasibility and nonlinearity. Moreover, applying Inverse DEA to new sectors such as healthcare, agriculture, and environmental and climate change issues holds great promise for future research. Overall, this paper sets the stage for further advancements in this promising approach.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46135372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The passive management approach offers conservative investors a way to reduce risk concerning the market. This investment strategy aims at replicating a specific index, such as the NASDAQ Composite or the FTSE100 index. The problem is that buying all the index’s assets incurs high rebalancing costs, and this harms future returns. The index tracking problem concerns building a portfolio that follows a specific benchmark with fewer transaction costs. Since a subset of assets is required to solve the index problem this class of problems is NP-hard, and in the past years, researchers have been studying solution approaches to obtain more practical tracking portfolios. This work brings an analysis, spanning the last three decades, of the advances in mathematical approaches for index tracking. The systematic literature review covered important issues, such as the most relevant research areas, solution methods, and model structures. Special attention was given to the exploration and analysis of metaheuristics applied to the index tracking problem.
{"title":"A systematic literature review on solution approaches for the index tracking problem in the last decade","authors":"Julio Cezar Soares Silva, Adiel Almeida Filho","doi":"10.1093/imaman/dpad007","DOIUrl":"https://doi.org/10.1093/imaman/dpad007","url":null,"abstract":"\u0000 The passive management approach offers conservative investors a way to reduce risk concerning the market. This investment strategy aims at replicating a specific index, such as the NASDAQ Composite or the FTSE100 index. The problem is that buying all the index’s assets incurs high rebalancing costs, and this harms future returns. The index tracking problem concerns building a portfolio that follows a specific benchmark with fewer transaction costs. Since a subset of assets is required to solve the index problem this class of problems is NP-hard, and in the past years, researchers have been studying solution approaches to obtain more practical tracking portfolios. This work brings an analysis, spanning the last three decades, of the advances in mathematical approaches for index tracking. The systematic literature review covered important issues, such as the most relevant research areas, solution methods, and model structures. Special attention was given to the exploration and analysis of metaheuristics applied to the index tracking problem.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":"abs/2306.01660 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"61003350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to: Electric vehicle manufacturers' decisions on investing in carbon-reduction technology under government subsidy: a Cournot game model","authors":"","doi":"10.1093/imaman/dpad003","DOIUrl":"https://doi.org/10.1093/imaman/dpad003","url":null,"abstract":"","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136022222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Advances in inverse data envelopment analysis: empowering performance assessment","authors":"Ali Emrouznejad, G. R. Amin","doi":"10.1093/imaman/dpad004","DOIUrl":"https://doi.org/10.1093/imaman/dpad004","url":null,"abstract":"","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43546180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ali Emrouznejad, M. Marra, Guo-liang Yang, Maria Michali
We highlight the state-of-the-art in the eco-efficiency measurement using Data Envelopment Analysis, including Malmquist-Luenberger productivity index. We also consider productivity change over time, provide directions for future studies in the field, and gather the most recent policy suggestions for governments, organisations and sectors for reducing CO2 emissions. A structured literature search of the Web of Science academic database reveals 311 papers published between 1989 and 2022. We carry out network analysis of citations to show the evolution of the literature in this research topic. In doing so, we (a) examine the key-route main path of knowledge flows, (b) provide basic bibliometric information about the most active journals and authors, (c) conduct a qualitative in-depth analysis of the identified most important studies and (d) identify the research fronts and relate them to the emerging issues on the topic researched, focusing on the most recent period between 2000 and 2022. Based on the insights of the literature review, the second part of this paper critically analyses the papers on the key-route (main path) of this subject. This review can be used as guidance and a starting point for researchers and practitioners that want to further investigate optimal policies to reach NetZero.
{"title":"Eco-efficiency considering NetZero and data envelopment analysis: a critical literature review","authors":"Ali Emrouznejad, M. Marra, Guo-liang Yang, Maria Michali","doi":"10.1093/imaman/dpad002","DOIUrl":"https://doi.org/10.1093/imaman/dpad002","url":null,"abstract":"We highlight the state-of-the-art in the eco-efficiency measurement using Data Envelopment Analysis, including Malmquist-Luenberger productivity index. We also consider productivity change over time, provide directions for future studies in the field, and gather the most recent policy suggestions for governments, organisations and sectors for reducing CO2 emissions. A structured literature search of the Web of Science academic database reveals 311 papers published between 1989 and 2022. We carry out network analysis of citations to show the evolution of the literature in this research topic. In doing so, we (a) examine the key-route main path of knowledge flows, (b) provide basic bibliometric information about the most active journals and authors, (c) conduct a qualitative in-depth analysis of the identified most important studies and (d) identify the research fronts and relate them to the emerging issues on the topic researched, focusing on the most recent period between 2000 and 2022. Based on the insights of the literature review, the second part of this paper critically analyses the papers on the key-route (main path) of this subject. This review can be used as guidance and a starting point for researchers and practitioners that want to further investigate optimal policies to reach NetZero.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45670366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper derives an inspection policy for an economic production quantity (EPQ) model under the assumption that a process may produce non-conforming (NC) items. In various stages of a production process, a department receiving an order uses a single sampling inspection policy to detect NC items. Under such a policy, a lot is accepted if the number of NC items in the inspected sample is equal to or less than the acceptance number. The proposed model considers both EPQ- and quality-related costs. Moreover, economic production order quantity, sample size, and acceptance number are considered decision variables. A numerical example is presented, and a set of sensitivity analysis are provided to highlight the effectiveness of the proposed model. The results reveal that when the inspection cost is high, the classical EPQ model achieves a lower expected total cost for the production system compared to the EPQ model with the inspection. In contrast, when the NC cost is high, the EPQ model with the inspection policy outperforms the classical EPQ model, which can significantly decrease the expected total cost.
{"title":"The economic production quantity model with optimal single sampling inspection","authors":"M. Nakhaeinejad","doi":"10.1093/imaman/dpad001","DOIUrl":"https://doi.org/10.1093/imaman/dpad001","url":null,"abstract":"\u0000 This paper derives an inspection policy for an economic production quantity (EPQ) model under the assumption that a process may produce non-conforming (NC) items. In various stages of a production process, a department receiving an order uses a single sampling inspection policy to detect NC items. Under such a policy, a lot is accepted if the number of NC items in the inspected sample is equal to or less than the acceptance number. The proposed model considers both EPQ- and quality-related costs. Moreover, economic production order quantity, sample size, and acceptance number are considered decision variables. A numerical example is presented, and a set of sensitivity analysis are provided to highlight the effectiveness of the proposed model. The results reveal that when the inspection cost is high, the classical EPQ model achieves a lower expected total cost for the production system compared to the EPQ model with the inspection. In contrast, when the NC cost is high, the EPQ model with the inspection policy outperforms the classical EPQ model, which can significantly decrease the expected total cost.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45468749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-21DOI: 10.2533/chimia.2022.1005
Cristina Manatschal, Raimund Dutzler
The SLC11/NRAMP proteins constitute a conserved family of metal ion transporters that are expressed in all kingdoms of life. In humans, the two paralogs DMT1 and NRMP1 play an important role in iron homeostasis and the defense against pathogens. SLC11 transporters have evolved an exquisite selectivity for transition metal ions, which facilitates their efficient transport from a large background of Ca2+ and Mg2+. This is accomplished by the evolution of a conserved binding site, which contains besides promiscuous hard ligands, a methionine acting as soft ligand that exclusively coordinates transition metals and thus contributes to the exclusion of alkaline earth metal ions. This site is altered in a branch of prokaryotic family members, which are capable of transporting Mg2+, where the removal of the coordinating methionine and the accompanying expansion of the binding pocket captures this small ion in a hydrated state. The disposition of titratable residues in H+-coupled transition metal ion transporters, that are absent in uncoupled Mg2+ transporters, sheds light on potential coupling mechanisms. In combination, the discussed work has revealed detailed insight into transition metal ion transport and provides a basis for the development of inhibitors of DMT1 as strategy against iron overload disorders.
{"title":"The Structural Basis for Metal Ion Transport in the SLC11/NRAMP Family.","authors":"Cristina Manatschal, Raimund Dutzler","doi":"10.2533/chimia.2022.1005","DOIUrl":"10.2533/chimia.2022.1005","url":null,"abstract":"<p><p>The SLC11/NRAMP proteins constitute a conserved family of metal ion transporters that are expressed in all kingdoms of life. In humans, the two paralogs DMT1 and NRMP1 play an important role in iron homeostasis and the defense against pathogens. SLC11 transporters have evolved an exquisite selectivity for transition metal ions, which facilitates their efficient transport from a large background of Ca2+ and Mg2+. This is accomplished by the evolution of a conserved binding site, which contains besides promiscuous hard ligands, a methionine acting as soft ligand that exclusively coordinates transition metals and thus contributes to the exclusion of alkaline earth metal ions. This site is altered in a branch of prokaryotic family members, which are capable of transporting Mg2+, where the removal of the coordinating methionine and the accompanying expansion of the binding pocket captures this small ion in a hydrated state. The disposition of titratable residues in H+-coupled transition metal ion transporters, that are absent in uncoupled Mg2+ transporters, sheds light on potential coupling mechanisms. In combination, the discussed work has revealed detailed insight into transition metal ion transport and provides a basis for the development of inhibitors of DMT1 as strategy against iron overload disorders.</p>","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":"24 1","pages":"1005-1010"},"PeriodicalIF":1.2,"publicationDate":"2022-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83059928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the rise of e-commerce, an increasing number of retailers concentrate on the online channel to sell their products (strategy O), while some retailers select online and offline combined retailing. That is, the retailers introduce an offline experience store in addition to their online channels (strategy B). However, there is little literature on which strategies are better when a retailer’s intrusion is considered. This paper constructs a competitive system in which the incumbent is a well-established pure online retailer and the new entrant will decide which strategy to select, strategy O or strategy B. The hotelling model is applied to represent the competitive market of both retailers through consumers’ asymmetrical preference for products, and Nash games under two strategies are built. Through comparing equilibrium solutions, we show that when consumers prefer the incumbent’s product, Online and offline retailing is an effective strategy for the new entrant to compete with the incumbent. Meanwhile, the incumbent’s advantage does not always benefit him. Consumers’ asymmetrical preference for products may intensify the competition between them and hurt their profits, but the new entrant can benefit from providing offline retailing under most cases.
{"title":"Channel encroachment strategy through pure online or combined offline retailing","authors":"Sheng Chen, Ruidong Zhao","doi":"10.1093/imaman/dpac014","DOIUrl":"https://doi.org/10.1093/imaman/dpac014","url":null,"abstract":"\u0000 With the rise of e-commerce, an increasing number of retailers concentrate on the online channel to sell their products (strategy O), while some retailers select online and offline combined retailing. That is, the retailers introduce an offline experience store in addition to their online channels (strategy B). However, there is little literature on which strategies are better when a retailer’s intrusion is considered. This paper constructs a competitive system in which the incumbent is a well-established pure online retailer and the new entrant will decide which strategy to select, strategy O or strategy B. The hotelling model is applied to represent the competitive market of both retailers through consumers’ asymmetrical preference for products, and Nash games under two strategies are built. Through comparing equilibrium solutions, we show that when consumers prefer the incumbent’s product, Online and offline retailing is an effective strategy for the new entrant to compete with the incumbent. Meanwhile, the incumbent’s advantage does not always benefit him. Consumers’ asymmetrical preference for products may intensify the competition between them and hurt their profits, but the new entrant can benefit from providing offline retailing under most cases.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45297750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper considers an unobservable queue with adjustable service rate and strategic customers. A queueing-game-theoretic model is built to capture the interaction between the server’s service rate and customers’ joining decisions. Iterative and recursive methods are used to derive the steady-state distribution and the expected sojourn time in the queue. We obtain customers’ equilibrium and socially optimal joining strategies under two information scenarios which are unobservable and partially unobservable queues, separately. It is found that there are four equilibrium joining strategies at most in the fully unobservable queue and two equilibrium joining strategies in the almost unobservable queue. Interestingly, the social optimal arrival rate is between the minimum and maximum stable equilibria. Thus, in most cases, managers need to charge a price to induce the social optimal customers’ behavior. However, if the minimum equilibrium is achieved, managers are required to provide a subsidy to maximize the social welfare. unobservable queue; $(m, N)$ policy; equilibrium strategy; social welfare.
{"title":"Strategic joining rules in unobservable queues with dynamic service rate","authors":"Shuangfeng Ma, Wei Guo","doi":"10.1093/imaman/dpac013","DOIUrl":"https://doi.org/10.1093/imaman/dpac013","url":null,"abstract":"\u0000 This paper considers an unobservable queue with adjustable service rate and strategic customers. A queueing-game-theoretic model is built to capture the interaction between the server’s service rate and customers’ joining decisions. Iterative and recursive methods are used to derive the steady-state distribution and the expected sojourn time in the queue. We obtain customers’ equilibrium and socially optimal joining strategies under two information scenarios which are unobservable and partially unobservable queues, separately. It is found that there are four equilibrium joining strategies at most in the fully unobservable queue and two equilibrium joining strategies in the almost unobservable queue. Interestingly, the social optimal arrival rate is between the minimum and maximum stable equilibria. Thus, in most cases, managers need to charge a price to induce the social optimal customers’ behavior. However, if the minimum equilibrium is achieved, managers are required to provide a subsidy to maximize the social welfare. unobservable queue; $(m, N)$ policy; equilibrium strategy; social welfare.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48243969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper we propose an integrated model for optimising the process mean, the price of products, and the production quantity. This optimisation is conducted considering the impact of price differentiation in an imperfectly segmented market where demand leakages are common. The products that are produced by the production process are assigned to two market segments using sampling inspection. For optimisation of the process mean, pricing, and production quantities, a multi-objective model is formulated that maximises (i) The expected total risk-adjusted profit across segments for a risk-tolerant firm, (ii) The satisficing level, that is, the probability of exceeding a target set for total risk-adjusted expected profit, and (iii) The two conflicting objectives, expected total risk-adjusted profit and satisficing level. Depending on the complexity of models, either derivative-based closed form solutions or heuristic solution procedures are developed. The problem finds applications in process industries. A detailed numerical simulation is performed to corroborate the models, and it shows that a higher risk aversion results in a lower total expected risk-adjusted profit but a higher probability of achieving the target profit.
{"title":"Process mean selection and price differentiation in an imperfectly segmented market for a risk-averse firm","authors":"Syed Asif Raza, Srikrishna Madhumohan Govindaluri","doi":"10.1093/imaman/dpac012","DOIUrl":"https://doi.org/10.1093/imaman/dpac012","url":null,"abstract":"\u0000 In this paper we propose an integrated model for optimising the process mean, the price of products, and the production quantity. This optimisation is conducted considering the impact of price differentiation in an imperfectly segmented market where demand leakages are common. The products that are produced by the production process are assigned to two market segments using sampling inspection. For optimisation of the process mean, pricing, and production quantities, a multi-objective model is formulated that maximises (i) The expected total risk-adjusted profit across segments for a risk-tolerant firm, (ii) The satisficing level, that is, the probability of exceeding a target set for total risk-adjusted expected profit, and (iii) The two conflicting objectives, expected total risk-adjusted profit and satisficing level. Depending on the complexity of models, either derivative-based closed form solutions or heuristic solution procedures are developed. The problem finds applications in process industries. A detailed numerical simulation is performed to corroborate the models, and it shows that a higher risk aversion results in a lower total expected risk-adjusted profit but a higher probability of achieving the target profit.","PeriodicalId":56296,"journal":{"name":"IMA Journal of Management Mathematics","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49127882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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