Hongfei Guo, X. Yu, Xinhua Wang, Lei Guo, Liancheng Xu, Ran Lu
As students in online courses usually show differences in their cognitive levels and lack communication with teachers, it is difficult for teachers to grasp student perceptions of the importance of knowledge-points and to develop personalized teaching. Though recent studies have paid attention to this topic, existing methods fail to calculate the importance of every knowledge-point for each student. Moreover, some studies are based on expert analysis, are not data-driven, and hence are inapplicable to large-scale online scenarios. To address these issues, this article proposes a personal topic rank (PTR) as a solution, which links students and concepts to generate a personalized knowledge concept map. Then, the authors present a novel PTR method to calculate the importance of knowledge-points, wherein student mastery of knowledge-points, student understanding, and the knowledge-point itself are considered simultaneously. This article conducts extensive experiments on a real-world dataset to demonstrate that the method can achieve better results than baselines.
{"title":"Discovering Knowledge-Point Importance From the Learning-Evaluation Data","authors":"Hongfei Guo, X. Yu, Xinhua Wang, Lei Guo, Liancheng Xu, Ran Lu","doi":"10.4018/ijdet.302012","DOIUrl":"https://doi.org/10.4018/ijdet.302012","url":null,"abstract":"As students in online courses usually show differences in their cognitive levels and lack communication with teachers, it is difficult for teachers to grasp student perceptions of the importance of knowledge-points and to develop personalized teaching. Though recent studies have paid attention to this topic, existing methods fail to calculate the importance of every knowledge-point for each student. Moreover, some studies are based on expert analysis, are not data-driven, and hence are inapplicable to large-scale online scenarios. To address these issues, this article proposes a personal topic rank (PTR) as a solution, which links students and concepts to generate a personalized knowledge concept map. Then, the authors present a novel PTR method to calculate the importance of knowledge-points, wherein student mastery of knowledge-points, student understanding, and the knowledge-point itself are considered simultaneously. This article conducts extensive experiments on a real-world dataset to demonstrate that the method can achieve better results than baselines.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129294184","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}
Newarney Torrezão da Costa, Denis José Almeida, Gustavo Prado Oliveira, M. A. Fernandes
Personalized sequencing and recommendation of pedagogical actions in virtual learning environments are relevant aspects in promoting an effective learning process with computer-aided support. Hence, this work investigates the use of automated planning to sequence these actions according to student profiles. Actions are modeled to correspond to the cognitive process described by Bloom’s Taxonomy, and the student profile is set using the Revised Approaches to Studying Inventory. Both models share theoretical foundations linked to the cognitive process, and the mapping of these two theories is one of the contributions merged into this study. In planning, through use of a genetic algorithm and the problem formulation as an optimization problem, one can correctly manage the search for good solutions, as demonstrated in this work. Through use of Digital Bloom’s Taxonomy, one arrives at a recommend set of actions. Experiments were performed using 41 students. The results were promising and demonstrate the viability of the proposal.
{"title":"Customized Pedagogical Recommendation Using Automated Planning for Sequencing Based on Bloom's Taxonomy","authors":"Newarney Torrezão da Costa, Denis José Almeida, Gustavo Prado Oliveira, M. A. Fernandes","doi":"10.4018/ijdet.296700","DOIUrl":"https://doi.org/10.4018/ijdet.296700","url":null,"abstract":"Personalized sequencing and recommendation of pedagogical actions in virtual learning environments are relevant aspects in promoting an effective learning process with computer-aided support. Hence, this work investigates the use of automated planning to sequence these actions according to student profiles. Actions are modeled to correspond to the cognitive process described by Bloom’s Taxonomy, and the student profile is set using the Revised Approaches to Studying Inventory. Both models share theoretical foundations linked to the cognitive process, and the mapping of these two theories is one of the contributions merged into this study. In planning, through use of a genetic algorithm and the problem formulation as an optimization problem, one can correctly manage the search for good solutions, as demonstrated in this work. Through use of Digital Bloom’s Taxonomy, one arrives at a recommend set of actions. Experiments were performed using 41 students. The results were promising and demonstrate the viability of the proposal.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127096761","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}
Video platform is not only a social tool, but also an educational tool.The survey found that Vietnamese Chinese learners widely use YouTube to learn Chinese. However, there is not much research on it. Under the guidance of constructivism, language acquisition theory and immersion theory, this study aims to explore the effectiveness of using YouTube for Chinese teaching. Through the comprehensive methods of questionnaire survey and teaching experiment, the study found that the use of YouTube teaching has a positive impact on Chinese learning. They generally believe that YouTube creates a more real language environment, which is conducive to Chinese learning.
{"title":"Research on the Application of Chinese Teaching Based on Social Media Video Platforms","authors":"Guihua Wang, Guoxiang Zhou, Zhe Li","doi":"10.4018/ijdet.296699","DOIUrl":"https://doi.org/10.4018/ijdet.296699","url":null,"abstract":"Video platform is not only a social tool, but also an educational tool.The survey found that Vietnamese Chinese learners widely use YouTube to learn Chinese. However, there is not much research on it. Under the guidance of constructivism, language acquisition theory and immersion theory, this study aims to explore the effectiveness of using YouTube for Chinese teaching. Through the comprehensive methods of questionnaire survey and teaching experiment, the study found that the use of YouTube teaching has a positive impact on Chinese learning. They generally believe that YouTube creates a more real language environment, which is conducive to Chinese learning.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123958104","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 reports an empirical investigation of the effects of school teachers’ self-efficacy and self-concept on their perceived ICT usability. It employed a descriptive survey method within an ex-post-facto research design taking 300 teachers as samples from purposively selected 50 Indian schools. The findings revealed that self-efficacy and self-concept discretely had a positive effect on teachers’ perceived ICT usability although self-concept was found to have a deeper impact in comparison to self-efficacy. But the two variables operated simultaneously had a more significant and stronger positive effect on the teachers’ perceived ICT usability. For every 1 standard unit increase in self-efficacy and in self-concept, the perceived ICT usability will be increased by 0.95 standard units. Based on this regression output authors proposed the TAM3+ as an extension of the TAM3 by adding a new domain as users’ ‘subjective self’ encompassing self-efficacy and self-concept significantly affecting their perceived ease of technology use.
{"title":"Subject-Self Affecting on Teachers' Perceived ICT Usability: A Proposition for TAM3+","authors":"A. Kundu, Kedar Nath Dey, Tripti Bej","doi":"10.4018/ijdet.295980","DOIUrl":"https://doi.org/10.4018/ijdet.295980","url":null,"abstract":"This study reports an empirical investigation of the effects of school teachers’ self-efficacy and self-concept on their perceived ICT usability. It employed a descriptive survey method within an ex-post-facto research design taking 300 teachers as samples from purposively selected 50 Indian schools. The findings revealed that self-efficacy and self-concept discretely had a positive effect on teachers’ perceived ICT usability although self-concept was found to have a deeper impact in comparison to self-efficacy. But the two variables operated simultaneously had a more significant and stronger positive effect on the teachers’ perceived ICT usability. For every 1 standard unit increase in self-efficacy and in self-concept, the perceived ICT usability will be increased by 0.95 standard units. Based on this regression output authors proposed the TAM3+ as an extension of the TAM3 by adding a new domain as users’ ‘subjective self’ encompassing self-efficacy and self-concept significantly affecting their perceived ease of technology use.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"51 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132365834","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}
Toshiki Nishio, Kousuke Mouri, Takafumi Tanaka, M. Okamoto, Y. Matsubara
This paper describes the effects of a pairing method based on digital textbook logs and learners’ artifacts in conceptual modeling exercises. We developed a digital textbook system called Smart E-textbook Application (SEA) and a conceptual modeling tool called KIfU 3.0 to collect conceptual modeling activity logs in exercises. This study proposes a method that makes pairs of learners for group work by considering the characteristics of the artifacts created by them and digital textbook logs. An initial evaluation was conducted to evaluate the learning effects of our proposed pairing method compared to the random pairing method. From its results, this study found the discussion patterns and digital textbook browsing status in the maximum value of improvement and deterioration points of learners’ artifacts in the conceptual modeling.
{"title":"Effects of Pairing Methods Based on Digital Textbook Logs and Learner Artifacts in Conceptual Modeling Exercises","authors":"Toshiki Nishio, Kousuke Mouri, Takafumi Tanaka, M. Okamoto, Y. Matsubara","doi":"10.4018/ijdet.296703","DOIUrl":"https://doi.org/10.4018/ijdet.296703","url":null,"abstract":"This paper describes the effects of a pairing method based on digital textbook logs and learners’ artifacts in conceptual modeling exercises. We developed a digital textbook system called Smart E-textbook Application (SEA) and a conceptual modeling tool called KIfU 3.0 to collect conceptual modeling activity logs in exercises. This study proposes a method that makes pairs of learners for group work by considering the characteristics of the artifacts created by them and digital textbook logs. An initial evaluation was conducted to evaluate the learning effects of our proposed pairing method compared to the random pairing method. From its results, this study found the discussion patterns and digital textbook browsing status in the maximum value of improvement and deterioration points of learners’ artifacts in the conceptual modeling.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134290891","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 Covid-19 pandemic constrained higher education institutions to switch to online teaching, which led to major changes in students’ learning behavior, affecting their overall performance. Thus, students’ academic performance needs to be meticulously monitored to help institutions identify students at risk of academic failure, preventing them from dropping out of the program or graduating late. This paper proposes a CGPA Predicting Model (CPM) that detects poor academic performance by predicting their graduation cumulative grade point average (CGPA). The proposed model uses a two-layer process that provides students with an estimated final CGPA, given their progress in second- and third-year courses. This work allows academic advisors to make suitable remedial arrangements to improve students’ academic performance. Through extensive simulations on a data set related to students registered in undergraduate information technology program gathered over the years, we demonstrate that the CPM attains accurate performance predictions compared to benchmark methods.
{"title":"Predicting Student Performance to Improve Academic Advising Using the Random Forest Algorithm","authors":"Mirna Nachouki, M. A. Naaj","doi":"10.4018/ijdet.296702","DOIUrl":"https://doi.org/10.4018/ijdet.296702","url":null,"abstract":"The Covid-19 pandemic constrained higher education institutions to switch to online teaching, which led to major changes in students’ learning behavior, affecting their overall performance. Thus, students’ academic performance needs to be meticulously monitored to help institutions identify students at risk of academic failure, preventing them from dropping out of the program or graduating late. This paper proposes a CGPA Predicting Model (CPM) that detects poor academic performance by predicting their graduation cumulative grade point average (CGPA). The proposed model uses a two-layer process that provides students with an estimated final CGPA, given their progress in second- and third-year courses. This work allows academic advisors to make suitable remedial arrangements to improve students’ academic performance. Through extensive simulations on a data set related to students registered in undergraduate information technology program gathered over the years, we demonstrate that the CPM attains accurate performance predictions compared to benchmark methods.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133524295","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 represented dimensions from the Diffusion of Innovations theory and the Community of Inquiry model to explore the adoption of web-conferencing. It used logistic regression to model the likelihood of adopting web-conferencing in online teaching with data collected from 66 college online instructors. In the logistic regression analyses, measures of the instructors’ perception of the instructional benefits of web-conferencing, perception of web-conferencing as a tool for creating social presence and teaching presence, and perception of barriers of using web-conferencing in online instruction were the independent variables, and the binary dependent variable represented the instructors’ adoption or non-adoption of the web-conferencing innovation. The results of the full logistic regression model (with all three independent variables) and the reduced models (with one or two independent variables at a time) are reported and implications for promoting web-conferencing adoption and future research are discussed.
{"title":"Adopting Web Conferencing in Online Teaching: A Perspective From Logistic Regression","authors":"Yangzi Sun, J. Beriswill, M. Allen","doi":"10.4018/ijdet.296701","DOIUrl":"https://doi.org/10.4018/ijdet.296701","url":null,"abstract":"This study represented dimensions from the Diffusion of Innovations theory and the Community of Inquiry model to explore the adoption of web-conferencing. It used logistic regression to model the likelihood of adopting web-conferencing in online teaching with data collected from 66 college online instructors. In the logistic regression analyses, measures of the instructors’ perception of the instructional benefits of web-conferencing, perception of web-conferencing as a tool for creating social presence and teaching presence, and perception of barriers of using web-conferencing in online instruction were the independent variables, and the binary dependent variable represented the instructors’ adoption or non-adoption of the web-conferencing innovation. The results of the full logistic regression model (with all three independent variables) and the reduced models (with one or two independent variables at a time) are reported and implications for promoting web-conferencing adoption and future research are discussed.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120854726","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}
F. Ouyang, Xu Li, Pengcheng Jiao, Xian Peng, Wenzhi Chen
The design of social learning analytics (SLA) tools has become a practical means to make available learning information with a goal to improve students’ regulation, reflection, and engagement in online learning. This design-based research uses the multi-method analytics to iteratively design, implement, and modify the SLA tool that makes available social, topic, and cognitive information to students in online discussions. This tool demonstrates students’ online discussions from social, sematic, and cognitive aspects. This research further uses online questionnaire and interview methods to investigate students’ perceptions about the tool’s usefulness and usability. After experiencing this tool, students proposed critical feedback for tool improvement from the network visualization, peer reference, and explanation support perspectives. Overall, the SLA tool is a beneficial tool to foster students’ awareness of their own learning and peer learning process, to improve students’ regulation and reflection of learning, and eventually improve student engagement in online discussions.
{"title":"The Three-Iterative Design and Implementation of a Student-Facing Social Learning Analytics Tool","authors":"F. Ouyang, Xu Li, Pengcheng Jiao, Xian Peng, Wenzhi Chen","doi":"10.4018/ijdet.286738","DOIUrl":"https://doi.org/10.4018/ijdet.286738","url":null,"abstract":"The design of social learning analytics (SLA) tools has become a practical means to make available learning information with a goal to improve students’ regulation, reflection, and engagement in online learning. This design-based research uses the multi-method analytics to iteratively design, implement, and modify the SLA tool that makes available social, topic, and cognitive information to students in online discussions. This tool demonstrates students’ online discussions from social, sematic, and cognitive aspects. This research further uses online questionnaire and interview methods to investigate students’ perceptions about the tool’s usefulness and usability. After experiencing this tool, students proposed critical feedback for tool improvement from the network visualization, peer reference, and explanation support perspectives. Overall, the SLA tool is a beneficial tool to foster students’ awareness of their own learning and peer learning process, to improve students’ regulation and reflection of learning, and eventually improve student engagement in online discussions.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133423524","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}
Sávio Resende Guadelupe, Danilo P. Freitas, P. V. R. Carvalho, Alessandro Jatobá
This article presents an observational qualitative study regarding the use of agile methodologies in implementing project-based student assessment procedures in higher education courses. The study comprised 32 students enrolled in an online Biology class in a public university in Rio de Janeiro, Brazil. Students underwent two types of activities: first using traditional project-based learning; second using an agile approach based on the EduScum methodology. Results demonstrated that the agile methodology enforced student engagement, especially collaboration aspects. Interactions between students and teachers became more acute and straightforward. Moreover, it became easier for teachers to monitor students' performance throughout the course. This, this study provides highlights to enable schools to improve students' assessment procedures in distance education courses
{"title":"Monitoring Student Performance Through an Agile Project-Based Assessment Strategy for Distance Higher Education","authors":"Sávio Resende Guadelupe, Danilo P. Freitas, P. V. R. Carvalho, Alessandro Jatobá","doi":"10.4018/ijdet.286739","DOIUrl":"https://doi.org/10.4018/ijdet.286739","url":null,"abstract":"This article presents an observational qualitative study regarding the use of agile methodologies in implementing project-based student assessment procedures in higher education courses. The study comprised 32 students enrolled in an online Biology class in a public university in Rio de Janeiro, Brazil. Students underwent two types of activities: first using traditional project-based learning; second using an agile approach based on the EduScum methodology. Results demonstrated that the agile methodology enforced student engagement, especially collaboration aspects. Interactions between students and teachers became more acute and straightforward. Moreover, it became easier for teachers to monitor students' performance throughout the course. This, this study provides highlights to enable schools to improve students' assessment procedures in distance education courses","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115472954","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}
Metacognitive intervention of listening has prevailed in L2 (Second Language) listening research in the past decade. However, rare research has linked metacognitive intervention with online listening. This study examines L2 learners’ development of metacognitive awareness of listening through online metacognitive listening practice. A set of online metacognitive listening exercises were constructed, based on a metacognitive cycle that regularly guides learners through metacognitive processes of listening. Thirty-nine low-proficiency Chinese university EFL listeners from one intact class participated in the study and did online listening practice as individual outside-class homework for 14 weeks. The development of metacognitive awareness was measured by MALQ and enriched by the learners' reflective notes. Results reveal an inverted U-shape pattern in the development of metacognitive awareness and that the factors of metacognitive awareness develop asynchronously. Some factors appear more susceptible to listening task difficulty and more unstable in the development process.
{"title":"Development of L2 Listening Metacognitive Awareness via Online Metacognitive Listening Practice","authors":"Tao Pei, J. Suwanthep","doi":"10.4018/ijdet.286741","DOIUrl":"https://doi.org/10.4018/ijdet.286741","url":null,"abstract":"Metacognitive intervention of listening has prevailed in L2 (Second Language) listening research in the past decade. However, rare research has linked metacognitive intervention with online listening. This study examines L2 learners’ development of metacognitive awareness of listening through online metacognitive listening practice. A set of online metacognitive listening exercises were constructed, based on a metacognitive cycle that regularly guides learners through metacognitive processes of listening. Thirty-nine low-proficiency Chinese university EFL listeners from one intact class participated in the study and did online listening practice as individual outside-class homework for 14 weeks. The development of metacognitive awareness was measured by MALQ and enriched by the learners' reflective notes. Results reveal an inverted U-shape pattern in the development of metacognitive awareness and that the factors of metacognitive awareness develop asynchronously. Some factors appear more susceptible to listening task difficulty and more unstable in the development process.","PeriodicalId":298910,"journal":{"name":"Int. J. Distance Educ. Technol.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122673362","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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