We discuss here conceptual change and the formation of robust learning outcomes from the viewpoint of complex dynamic systems (CDS). The CDS view considers students’ conceptions as context dependent and multifaceted structures which depend on the context of their application. In the CDS view the conceptual patterns (i.e. intuitive conceptions here) may be robust in a certain situation but are not formed, at least not as robust ones, in another situation. The stability is then thought to arise dynamically in a variety of ways and not so much to mirror rigid ontological categories or static intuitive conceptions. We use computational modelling to understand the generic dynamic and emergent features of that phenomenon. The model is highly simplified and idealized, but it shows how context dependence, described here by an epistemic landscape structure, leads to the formation of context dependent robust states that can be viewed as attractors in learning, and how owing to the sharply defined nature of these states, learning appears as a progression of switches from one state to another, giving thus the appearance of conceptual change as switches from one robust state to another. Finally, we discuss the implications of the results in directing attention to the design of learning tasks and their structure, and how empirically accessible learning outcomes might be related to these underlying factors.
{"title":"Complex Dynamic Systems View on Conceptual Change: How a Picture of Students' Intuitive Conceptions Accrue from Dynamically Robust Task Dependent Learning Outcomes.","authors":"I. Koponen, Tommi Kokkonen, Maiji Nousiainen","doi":"10.29173/CMPLCT29332","DOIUrl":"https://doi.org/10.29173/CMPLCT29332","url":null,"abstract":"We discuss here conceptual change and the formation of robust learning outcomes from the viewpoint of complex dynamic systems (CDS). The CDS view considers students’ conceptions as context dependent and multifaceted structures which depend on the context of their application. In the CDS view the conceptual patterns (i.e. intuitive conceptions here) may be robust in a certain situation but are not formed, at least not as robust ones, in another situation. The stability is then thought to arise dynamically in a variety of ways and not so much to mirror rigid ontological categories or static intuitive conceptions. We use computational modelling to understand the generic dynamic and emergent features of that phenomenon. The model is highly simplified and idealized, but it shows how context dependence, described here by an epistemic landscape structure, leads to the formation of context dependent robust states that can be viewed as attractors in learning, and how owing to the sharply defined nature of these states, learning appears as a progression of switches from one state to another, giving thus the appearance of conceptual change as switches from one robust state to another. Finally, we discuss the implications of the results in directing attention to the design of learning tasks and their structure, and how empirically accessible learning outcomes might be related to these underlying factors.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83382721","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 present special issue is yet one more collective endeavor in the area of educational research that demonstrates how the new science of complex dynamical systems could be applied in this domain. In social sciences, while the linear methodologies are, at the moment still the main stream, the appreciation of the new paradigm has already been growing, and a considerable body of research has been published recently in regular journals, special issues on complexity and edited book volumes. In physiology, behavioral sciences, economics and life sciences, complexity theory and nonlinear dynamics have been proven highly influential advancing the discipline. Education is no longer a late follower to those developments, but a privileged area where complex dynamical system (CDS) is by now an established paradigm. Complexity theory has inspired researchers and scholars working in education and curriculum studies to approach their subject matter from a different angle, and ask different questions, focusing on the processes through which things come to be what they are. It has also changed traditional ways of thinking, in qualitative as well as quantitative research, perhaps setting the stage for a paradigm shift. The foundation of the new science has been based on empirical studies that implement concepts of CDS,
{"title":"Special Issue: Proceedings of the Symposium on Complex Systems in Education","authors":"D. Stamovlasis, M. Koopmans","doi":"10.29173/CMPLCT29331","DOIUrl":"https://doi.org/10.29173/CMPLCT29331","url":null,"abstract":"The present special issue is yet one more collective endeavor in the area of educational research that demonstrates how the new science of complex dynamical systems could be applied in this domain. In social sciences, while the linear methodologies are, at the moment still the main stream, the appreciation of the new paradigm has already been growing, and a considerable body of research has been published recently in regular journals, special issues on complexity and edited book volumes. In physiology, behavioral sciences, economics and life sciences, complexity theory and nonlinear dynamics have been proven highly influential advancing the discipline. Education is no longer a late follower to those developments, but a privileged area where complex dynamical system (CDS) is by now an established paradigm. Complexity theory has inspired researchers and scholars working in education and curriculum studies to approach their subject matter from a different angle, and ask different questions, focusing on the processes through which things come to be what they are. It has also changed traditional ways of thinking, in qualitative as well as quantitative research, perhaps setting the stage for a paradigm shift. The foundation of the new science has been based on empirical studies that implement concepts of CDS,","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86721096","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 discusses investigations in science education addressing the nonlinear dynamical hypothesis. Learning science is a suitable field for applying interdisciplinary research and predominately for testing psychological theories. It was demonstrated that in this area the paradigm of complexity and nonlinear dynamics have offered theoretical advances and better interpretations of empirical data. Research showed that besides linear modes of behavior, sudden transitions occur in cognitive performance and this has questioned basic theoretical and epistemological assumptions. The neo-Piagetian framework and motivational theories offering constructs for serving as predictors in various model are the local theories which are embraced by the CDS meta-theory. Sudden transitions are modeled by catastrophe theory (CT) the analyses of which reveal the crucial role of certain variables, namely the bifurcation factors. Beyond a critical value of the bifurcation factor, the state variable splits into two-attractor regions and becomes bimodal. The bifurcation effect induces uncertainty and unpredictability in the system, which oscillates between two states entering the regime of chaos. Then in state variables such as learning outcomes and achievement, sudden transitions from success to failure are expected. Catastrophe theory explains unexpected phenomena associated with school failure, dropouts, illicit behaviors, sudden attitude change, and creativity. Moreover CT could contribute in elucidating theoretical debates and conflicting empirical evidences.
{"title":"The Dynamics of Cognitive Performance: What Has Been Learnt from Empirical Research in Science Education","authors":"D. Stamovlasis","doi":"10.29173/CMPLCT29333","DOIUrl":"https://doi.org/10.29173/CMPLCT29333","url":null,"abstract":"This paper discusses investigations in science education addressing the nonlinear dynamical hypothesis. Learning science is a suitable field for applying interdisciplinary research and predominately for testing psychological theories. It was demonstrated that in this area the paradigm of complexity and nonlinear dynamics have offered theoretical advances and better interpretations of empirical data. Research showed that besides linear modes of behavior, sudden transitions occur in cognitive performance and this has questioned basic theoretical and epistemological assumptions. The neo-Piagetian framework and motivational theories offering constructs for serving as predictors in various model are the local theories which are embraced by the CDS meta-theory. Sudden transitions are modeled by catastrophe theory (CT) the analyses of which reveal the crucial role of certain variables, namely the bifurcation factors. Beyond a critical value of the bifurcation factor, the state variable splits into two-attractor regions and becomes bimodal. The bifurcation effect induces uncertainty and unpredictability in the system, which oscillates between two states entering the regime of chaos. Then in state variables such as learning outcomes and achievement, sudden transitions from success to failure are expected. Catastrophe theory explains unexpected phenomena associated with school failure, dropouts, illicit behaviors, sudden attitude change, and creativity. Moreover CT could contribute in elucidating theoretical debates and conflicting empirical evidences.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81467036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article differentiates approaches to school-based teacher education. It contrasts the pervasive apprenticeship model, to a "naturally integrated" school-based teacher education program that we describe as a complex learning system. Rather than view teacher education as fragmented by separating educational theory (physically based on a university campus) and teaching practice (based in a school and resembling an apprenticeship), we favor an approach where all coursework is integrated with practice in a host school while maintaining close connections to the university. The latter model highlights learning as contextualized in school, focussed on the whole school, yet also informed by progressive educational thought. All participants in the school environment (not just university students) are at once both learners and teachers. Just as university-based aspects of teacher education suffer from a lack of practical relevance, we anticipate that any model of school-based teacher education will have to address the effects of context overwhelming theoretical learning, philosophical understandings, and generalization to other contexts. We claim that a complex learning system model is better able to mitigate these contextual effects. We propose an approach to address this issue through both "reduction" and "complexity".
{"title":"Integrated School-Based Teacher Education: From Apprenticeship to a Complex Learning System","authors":"Steve J. Collins, Hermia Ting","doi":"10.29173/CMPLCT28838","DOIUrl":"https://doi.org/10.29173/CMPLCT28838","url":null,"abstract":"This article differentiates approaches to school-based teacher education. It contrasts the pervasive apprenticeship model, to a \"naturally integrated\" school-based teacher education program that we describe as a complex learning system. Rather than view teacher education as fragmented by separating educational theory (physically based on a university campus) and teaching practice (based in a school and resembling an apprenticeship), we favor an approach where all coursework is integrated with practice in a host school while maintaining close connections to the university. The latter model highlights learning as contextualized in school, focussed on the whole school, yet also informed by progressive educational thought. All participants in the school environment (not just university students) are at once both learners and teachers. Just as university-based aspects of teacher education suffer from a lack of practical relevance, we anticipate that any model of school-based teacher education will have to address the effects of context overwhelming theoretical learning, philosophical understandings, and generalization to other contexts. We claim that a complex learning system model is better able to mitigate these contextual effects. We propose an approach to address this issue through both \"reduction\" and \"complexity\".","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79688715","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}
L. Ludlow, Fiona Ell, Marilyn Cochran-Smith, A. Newton, K. Trefcer, Kelsey Klein, L. Grudnoff, M. Haigh, M. Hill
Our purpose is to provide an exploratory statistical representation of initial teacher education as a complex system comprised of dynamic influential elements. More precisely, we reveal what the system looks like for differently-positioned teacher education stakeholders based on our framework for gathering, statistically analyzing, and graphically representing the results of a unique exercise wherein the participants literally mapped the system as they perceived it. Through an iterative series of inter-related studies employing cluster analysis and multidimensional scaling procedures, we demonstrate how initial teacher education may be represented as a complex system comprised of interactive agents and attributes whose perceived relationships are a function of nested stakeholder-dependent simplex systems. Furthermore, we illustrate how certain propositions of complexity theory, such as boundaries, heterogeneity, multidimensionality and emergence, may be investigated and represented quantitatively.
{"title":"Visualizing Teacher Education as a Complex System: A Nested Simplex System Approach","authors":"L. Ludlow, Fiona Ell, Marilyn Cochran-Smith, A. Newton, K. Trefcer, Kelsey Klein, L. Grudnoff, M. Haigh, M. Hill","doi":"10.29173/CMPLCT26053","DOIUrl":"https://doi.org/10.29173/CMPLCT26053","url":null,"abstract":"Our purpose is to provide an exploratory statistical representation of initial teacher education as a complex system comprised of dynamic influential elements. More precisely, we reveal what the system looks like for differently-positioned teacher education stakeholders based on our framework for gathering, statistically analyzing, and graphically representing the results of a unique exercise wherein the participants literally mapped the system as they perceived it. Through an iterative series of inter-related studies employing cluster analysis and multidimensional scaling procedures, we demonstrate how initial teacher education may be represented as a complex system comprised of interactive agents and attributes whose perceived relationships are a function of nested stakeholder-dependent simplex systems. Furthermore, we illustrate how certain propositions of complexity theory, such as boundaries, heterogeneity, multidimensionality and emergence, may be investigated and represented quantitatively.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76042433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is considerable variation in the dynamical literature in how the term ‘complexity’ is used. While there have been several attempts to describe from an educational perspective what complexity encompasses, the term is frequently used without an explicit definition. To forge a shared understanding of what complexity means, the purpose of this article is to define the term for the field in a way that acknowledges the variety of use that is encountered in the education. Four perspectives on complexity are offered: 1) Information theory, 2) Cybernetics and general systems theory, 3) The use of complexity to describe scenarios of transformation and 4) Complexity as a metatheory. The implications of each of these four conceptualizations for educational research and practice are discussed.
{"title":"Perspectives on Complexity, Its Definition and Applications in the Field","authors":"M. Koopmans","doi":"10.29173/CMPLCT27611","DOIUrl":"https://doi.org/10.29173/CMPLCT27611","url":null,"abstract":"There is considerable variation in the dynamical literature in how the term ‘complexity’ is used. While there have been several attempts to describe from an educational perspective what complexity encompasses, the term is frequently used without an explicit definition. To forge a shared understanding of what complexity means, the purpose of this article is to define the term for the field in a way that acknowledges the variety of use that is encountered in the education. Four perspectives on complexity are offered: 1) Information theory, 2) Cybernetics and general systems theory, 3) The use of complexity to describe scenarios of transformation and 4) Complexity as a metatheory. The implications of each of these four conceptualizations for educational research and practice are discussed.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75928941","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}
Pub Date : 2016-12-31DOI: 10.1515/9783839435175-fm
{"title":"Frontmatter","authors":"","doi":"10.1515/9783839435175-fm","DOIUrl":"https://doi.org/10.1515/9783839435175-fm","url":null,"abstract":"","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85949661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article describes the effectiveness and sustainability of teacher professional development interventions from a complexity view point as well as a more ‘standard’ viewpoint. The first aim of this study is to give a theoretical overview of effective aspects of interventions regarding teachers’ professionalizing using recent literature. The second aim is to re-interpret effectiveness and effectiveness studies using a complexity approach. The third aim is to empirically illustrate a complexity approach to the effectiveness of interventions using a multiple case study We have described intervention specific aspects, teacher specific aspects, context specific aspects and implementation specific aspects and have shown in the cases that during an intervention these aspects intertwine and act as a complex dynamic system. The complexity approach to interventions has implications for future empirical research as well as for the design of interventions. In future research, results of small scale and large scale research should be combined, in order to obtain a better insight in all relevant aspects and their effect on teachers’ behavior. Research ought to concentrate on the effects that all contextual aspects have intertwiningly in order to design more effective interventions and with better implementation processes.
{"title":"A complexity approach to investigating the effectiveness of an intervention for lower grade teachers on teaching science","authors":"A. Wetzels, Henderien W. Steenbeek, P. Geert","doi":"10.29173/CMPLCT23022","DOIUrl":"https://doi.org/10.29173/CMPLCT23022","url":null,"abstract":"This article describes the effectiveness and sustainability of teacher professional development interventions from a complexity view point as well as a more ‘standard’ viewpoint. The first aim of this study is to give a theoretical overview of effective aspects of interventions regarding teachers’ professionalizing using recent literature. The second aim is to re-interpret effectiveness and effectiveness studies using a complexity approach. The third aim is to empirically illustrate a complexity approach to the effectiveness of interventions using a multiple case study We have described intervention specific aspects, teacher specific aspects, context specific aspects and implementation specific aspects and have shown in the cases that during an intervention these aspects intertwine and act as a complex dynamic system. The complexity approach to interventions has implications for future empirical research as well as for the design of interventions. In future research, results of small scale and large scale research should be combined, in order to obtain a better insight in all relevant aspects and their effect on teachers’ behavior. Research ought to concentrate on the effects that all contextual aspects have intertwiningly in order to design more effective interventions and with better implementation processes.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86918782","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 utilizes the theoretical framework of complexity theory to compare and contrast leadership and educational change in two urban schools. Drawing on the notion of a complex adaptive system—an interdependent network of interacting elements that learns and evolves in adapting to an ever-shifting context—our case studies seek to reveal the complexities, tensions, characteristics, and related implications for school leadership derived from using this heuristic to understand adaptive change. In particular, we highlight the need to disrupt the status quo as a precursor to adaptive change, the power generated by distributing authority through decentralized networks, the importance of relational trust, and the impact of school culture.
{"title":"Complex Adaptive Schools: Educational Leadership and School Change","authors":"Brad Kershner, P. McQuillan","doi":"10.29173/CMPLCT23029","DOIUrl":"https://doi.org/10.29173/CMPLCT23029","url":null,"abstract":"This paper utilizes the theoretical framework of complexity theory to compare and contrast leadership and educational change in two urban schools. Drawing on the notion of a complex adaptive system—an interdependent network of interacting elements that learns and evolves in adapting to an ever-shifting context—our case studies seek to reveal the complexities, tensions, characteristics, and related implications for school leadership derived from using this heuristic to understand adaptive change. In particular, we highlight the need to disrupt the status quo as a precursor to adaptive change, the power generated by distributing authority through decentralized networks, the importance of relational trust, and the impact of school culture.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78231950","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 goal of this research study has been to develop, implement, and evaluate a school reform design experiment at a continuation high school with low-income, low-performing underrepresented minority students. The complexity sciences served as a theoretical framework for this design experiment. Treating an innovative college preparatory program as a nested complex adaptive system within a larger complex adaptive system, the school, we used features of complex adaptive systems (equilibrium, emergence, self-organization, and feedback loops) as a framework to design a strategy for school reform. The goal was to create an environment for change by pulling the school far from equilibrium using a strategy we call “purposeful perturbations” to disrupt the stable state of the school in a purposeful way. Over the four years of the study, several tipping points were reached, and we developed agent-based simulation models that capture important dynamic properties of the reform at these points. The study draws upon complexity theory in multiple ways that have supported improved education for low-achieving students.
{"title":"Navigating the Turbulent Waters of School Reform Guided by Complexity Theory.","authors":"D. G. White, J. Levin","doi":"10.29173/CMPLCT24566","DOIUrl":"https://doi.org/10.29173/CMPLCT24566","url":null,"abstract":"The goal of this research study has been to develop, implement, and evaluate a school reform design experiment at a continuation high school with low-income, low-performing underrepresented minority students. The complexity sciences served as a theoretical framework for this design experiment. Treating an innovative college preparatory program as a nested complex adaptive system within a larger complex adaptive system, the school, we used features of complex adaptive systems (equilibrium, emergence, self-organization, and feedback loops) as a framework to design a strategy for school reform. The goal was to create an environment for change by pulling the school far from equilibrium using a strategy we call “purposeful perturbations” to disrupt the stable state of the school in a purposeful way. Over the four years of the study, several tipping points were reached, and we developed agent-based simulation models that capture important dynamic properties of the reform at these points. The study draws upon complexity theory in multiple ways that have supported improved education for low-achieving students.","PeriodicalId":43228,"journal":{"name":"Complicity-An International Journal of Complexity and Education","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74448343","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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