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Tao Zhang - One of the best experts on this subject based on the ideXlab platform.
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a bromo nitro redox Mediator of brch2no2 for efficient lithium oxygen batteries
Journal of Power Sources, 2021Co-Authors: Xiaoping Zhang, Junwen Deng, Ya Mao, Jingying Xie, Tao ZhangAbstract:Abstract The lithium−oxygen (Li–O2) battery is considered as a promising candidate for the next-generation energy storage systems owing to its high theoretic specific energy. However, the slow kinetics of Li–O2 batteries cause a high charging overpotential, which leads to poor cyclability. Redox Mediators are introduced as a promising tool to reduce the overpotentials of Li–O2 batteries. Unfortunately, the oxidized redox Mediators can diffuse to the lithium anode and induce undesirable reactions. This so-called “shuttle effect” leads to the consumption of the redox Mediators and the decrease of battery round-trip efficiency. In this work, an organic bromine, bromonitromethane (BrCH2NO2), can act bifunctionally as a redox Mediator and a lithium anode protective layer-forming agent for Li–O2 batteries. It generates bromine ion (Br−) and in situ forms a lithium anode protective layer via reducing on lithium anode. This layer suppresses the shuttle effect and allows efficient lithium ion (Li+) transfer. The superior cycling performance of batteries containing BrCH2NO2 demonstrates that the suitable bifunctional redox Mediator is important for highly efficient and stable Li–O2 batteries.
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anode interfacial layer formation via reductive ethyl detaching of organic iodide in lithium oxygen batteries
Nature Communications, 2019Co-Authors: Xiaoping Zhang, Yiyang Sun, Zhuang Sun, Chushu Yang, Tao ZhangAbstract:As soluble catalysts, redox Mediators can reduce the high charging overpotential of lithium-oxygen batteries by providing sufficient liquid-solid interface for lithium peroxide decomposition. However, the redox Mediators usually introduce undesirable reactions. In particular, the so-called “shuttle effect” leads to the loss of both the redox Mediators and electrical energy efficiency. In this study, an organic compound, triethylsulfonium iodide, is found to act bifunctionally as both a redox Mediator and a solid electrolyte interphase-forming agent for lithium-oxygen batteries. During charging, the organic iodide exhibits comparable lithium peroxide-oxidizing capability with inorganic iodides. Meanwhile, it in situ generates an interfacial layer on lithium anode via reductive ethyl detaching and the subsequent oxidation. This layer prevents the lithium anode from reacting with the redox Mediators and allows efficient lithium-ion transfer leading to dendrite-free lithium anode. Significantly improved cycling performance has been achieved by the bifunctional organic iodide redox Mediator. To fulfill the great promise of Li-O2 batteries, the high charge overpotential is a major challenge that has to be addressed. Here the authors introduce triethylsulfonium iodide as a redox Mediator as well as an enabler of a protective layer on Li anode, leading to notable electrochemical performance.
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anode interfacial layer formation via reductive ethyl detaching of organic iodide in lithium oxygen batteries
Nature Communications, 2019Co-Authors: Xiaoping Zhang, Yiyang Sun, Zhuang Sun, Chushu Yang, Tao ZhangAbstract:As soluble catalysts, redox Mediators can reduce the high charging overpotential of lithium-oxygen batteries by providing sufficient liquid-solid interface for lithium peroxide decomposition. However, the redox Mediators usually introduce undesirable reactions. In particular, the so-called "shuttle effect" leads to the loss of both the redox Mediators and electrical energy efficiency. In this study, an organic compound, triethylsulfonium iodide, is found to act bifunctionally as both a redox Mediator and a solid electrolyte interphase-forming agent for lithium-oxygen batteries. During charging, the organic iodide exhibits comparable lithium peroxide-oxidizing capability with inorganic iodides. Meanwhile, it in situ generates an interfacial layer on lithium anode via reductive ethyl detaching and the subsequent oxidation. This layer prevents the lithium anode from reacting with the redox Mediators and allows efficient lithium-ion transfer leading to dendrite-free lithium anode. Significantly improved cycling performance has been achieved by the bifunctional organic iodide redox Mediator.
Xiaoping Zhang - One of the best experts on this subject based on the ideXlab platform.
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a bromo nitro redox Mediator of brch2no2 for efficient lithium oxygen batteries
Journal of Power Sources, 2021Co-Authors: Xiaoping Zhang, Junwen Deng, Ya Mao, Jingying Xie, Tao ZhangAbstract:Abstract The lithium−oxygen (Li–O2) battery is considered as a promising candidate for the next-generation energy storage systems owing to its high theoretic specific energy. However, the slow kinetics of Li–O2 batteries cause a high charging overpotential, which leads to poor cyclability. Redox Mediators are introduced as a promising tool to reduce the overpotentials of Li–O2 batteries. Unfortunately, the oxidized redox Mediators can diffuse to the lithium anode and induce undesirable reactions. This so-called “shuttle effect” leads to the consumption of the redox Mediators and the decrease of battery round-trip efficiency. In this work, an organic bromine, bromonitromethane (BrCH2NO2), can act bifunctionally as a redox Mediator and a lithium anode protective layer-forming agent for Li–O2 batteries. It generates bromine ion (Br−) and in situ forms a lithium anode protective layer via reducing on lithium anode. This layer suppresses the shuttle effect and allows efficient lithium ion (Li+) transfer. The superior cycling performance of batteries containing BrCH2NO2 demonstrates that the suitable bifunctional redox Mediator is important for highly efficient and stable Li–O2 batteries.
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anode interfacial layer formation via reductive ethyl detaching of organic iodide in lithium oxygen batteries
Nature Communications, 2019Co-Authors: Xiaoping Zhang, Yiyang Sun, Zhuang Sun, Chushu Yang, Tao ZhangAbstract:As soluble catalysts, redox Mediators can reduce the high charging overpotential of lithium-oxygen batteries by providing sufficient liquid-solid interface for lithium peroxide decomposition. However, the redox Mediators usually introduce undesirable reactions. In particular, the so-called “shuttle effect” leads to the loss of both the redox Mediators and electrical energy efficiency. In this study, an organic compound, triethylsulfonium iodide, is found to act bifunctionally as both a redox Mediator and a solid electrolyte interphase-forming agent for lithium-oxygen batteries. During charging, the organic iodide exhibits comparable lithium peroxide-oxidizing capability with inorganic iodides. Meanwhile, it in situ generates an interfacial layer on lithium anode via reductive ethyl detaching and the subsequent oxidation. This layer prevents the lithium anode from reacting with the redox Mediators and allows efficient lithium-ion transfer leading to dendrite-free lithium anode. Significantly improved cycling performance has been achieved by the bifunctional organic iodide redox Mediator. To fulfill the great promise of Li-O2 batteries, the high charge overpotential is a major challenge that has to be addressed. Here the authors introduce triethylsulfonium iodide as a redox Mediator as well as an enabler of a protective layer on Li anode, leading to notable electrochemical performance.
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anode interfacial layer formation via reductive ethyl detaching of organic iodide in lithium oxygen batteries
Nature Communications, 2019Co-Authors: Xiaoping Zhang, Yiyang Sun, Zhuang Sun, Chushu Yang, Tao ZhangAbstract:As soluble catalysts, redox Mediators can reduce the high charging overpotential of lithium-oxygen batteries by providing sufficient liquid-solid interface for lithium peroxide decomposition. However, the redox Mediators usually introduce undesirable reactions. In particular, the so-called "shuttle effect" leads to the loss of both the redox Mediators and electrical energy efficiency. In this study, an organic compound, triethylsulfonium iodide, is found to act bifunctionally as both a redox Mediator and a solid electrolyte interphase-forming agent for lithium-oxygen batteries. During charging, the organic iodide exhibits comparable lithium peroxide-oxidizing capability with inorganic iodides. Meanwhile, it in situ generates an interfacial layer on lithium anode via reductive ethyl detaching and the subsequent oxidation. This layer prevents the lithium anode from reacting with the redox Mediators and allows efficient lithium-ion transfer leading to dendrite-free lithium anode. Significantly improved cycling performance has been achieved by the bifunctional organic iodide redox Mediator.
Andreu Terrén Glòria - One of the best experts on this subject based on the ideXlab platform.
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Blanqueig enzimàtic de pasta de kenaf emprant sistemes lacasa-mediador
Universitat Politècnica de Catalunya, 2013Co-Authors: Andreu Terrén GlòriaAbstract:Premi extraordinari doctorat curs 2012-2013, àmbit d’Enginyeria IndustrialLa present tesi s’emmarca dins d’una de les línies del Grup de Recerca Paperer i Gràfic (CIPAGRAF), del Departament d’Enginyeria Tèxtil i Paperera de l’Escola Tècnica Superior d’Enginyeries Industrial i Aeronàutica de Terrassa, encaminada a l’aplicacióde la Biotecnologia per desenvolupar nous sistemes enzimàtics per al blanqueig depastes i modificació de fibres cel·lulòsiques. La implantació d’etapes enzimàtiques en les seqüències de blanqueig de pasta de paper a nivell industrial continua essent, avui en dia, un dels principals reptes en el camp de la investigació paperera. La reducció de l’impacte ambiental, l’optimització de costos, així com el desenvolupament de productes paperers amb propietats noves i millorades, justifiquen l’estudi de noves seqüències enzimàtiques basades en l’aplicació de sistemes lacasa-mediador. La utilització d’una matèria prima renovable, el kenaf, està en sintonia amb el creixent interès de l’ús de fibres no fusteres per a l’obtenció de nous productes lignocel·lulòsics d’alt valor afegit. Així doncs, aquesta tesi es fonamenta en l’ús d’enzims per a blanquejar pasta de kenaf. Les seqüències de blanqueig enzimàtic estudiades consten de diferents tractaments amb el sistema lacasa-mediador (Etapa L). Les lacases utilitzades en aquesta etapa provenen dels fongs Pycnoporus cinnabarinus i Trametes villosa, les quals s’apliquen amb diferents mediadors naturals (compostos fenòlics derivats de la lignina) i amb un mediador sintètic. L’etapa enzimàtica es completa amb diferents etapes de blanqueig químic (quelant, peròxid d’hidrogen i peròxid d’hidrogen pressuritzat). Al final de les seqüències s’obtenen, en funció del mediador utilitzat en l’etapa enzimàtica, fibres de kenaf amb un alt contingut de cel·lulosa i altes blancors. En aquest sentit, en el transcurs de l’experimentació s’ha constatat la importància de la naturalesa química del mediador, ja que els diferents radicals fenoxi formats en l’etapa enzimàtica determinen la capacitat oxidativa del sistema lacasa-mediador. Per altra banda, els resultats obtinguts remarquen el paper de la composició química de la lignina de kenaf en el procés enzimàtic. La capacitat oxidativa de la lacasa augmenta en presència de pasta de kenaf i la quantitat d’àcids hexenurònics presents en la mateixa limita el grau de blancor assolit en els diferents tractaments, encara que el resultat final es semblant o superior a una pasta TCF convencional. L’aplicació de xilanases després de l’etapa enzimàtica lacasa-mediador es mostra efectiva en l’eliminació d’aquests àcids, essent una possible via de millora als tractaments proposats en la present tesi.The present thesis has been performed in the research group CIPAGRAF (Grup de Recerca Paperer i Gràfic) of the Departament d'Enginyeria Tèxtil i Paperera at the Escola Tècnica Superior d'Enginyeries Industrial i Aeronàutica de Terrassa. One of the research topics of the group is the application of enzymes in pulp biobleaching processes and in the modification of cellulosic fibers. The implementation of enzymatic stages in paper pulp bleaching sequences is, at present, one of the main challenges of the research in the paper industry. The application of laccase-Mediator systems can lead to a reduction of environmental impact and to cost optimization, as well as to the development of paper-derived products with novel and improved properties. The use of a renewable raw material -kenaf- is in accordance with the growing interest in the utilization of non-wood fibers for the production of new high-added value lignocellulosic products. Consequently, the present thesis is based on the use of enzymes for kenaf pulp bleaching. The enzymatic bleaching sequences studied involve different treatments with the laccase-Mediator system (Stage L). The two fungal enzymes used in this stage- Pycnoporus cinnabarinus and Trametes villosa laccases-have been assisted by different natural Mediators (lignin-derived phenolic compounds) and a synthetic one. The enzymatic stage has been completed with different chemical bleaching stages (chelating, hydrogen peroxide and pressurized hydrogen peroxide). At the end of the sequences, kenaf fibers with high cellulose levels and brightness were obtained. The significance of the chemical nature of the Mediator has been emphasized because the different phenoxy radicals formed in the enzymatic stage determine the oxidative capacity of the laccase-Mediator system. In addition, the results obtained also show the role of the chemical composition of kenaf lignin in the enzymatic process. The laccase oxidative capacity increases in the presence of kenaf pulp, and the amount of hexenuronic acids present limits the degree of brightness. Nevertheless, for the enzymatic treatments, the final results are similar to or better than for a conventional chlorine-free treatment. The application of xilanases after the laccase-Mediator stage has been shown to be efficient in hexenuronic acids removal, opening possible new improvements to the treatments reported in this work.Award-winnin
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Blanqueig enzimàtic de pasta de kenaf emprant sistemes lacasa-mediador
Universitat Politècnica de Catalunya, 2013Co-Authors: Andreu Terrén GlòriaAbstract:Premi extraordinari doctorat curs 2012-2013, àmbit d’Enginyeria IndustrialLa present tesi s’emmarca dins d’una de les línies del Grup de Recerca Paperer i Gràfic (CIPAGRAF), del Departament d’Enginyeria Tèxtil i Paperera de l’Escola Tècnica Superior d’Enginyeries Industrial i Aeronàutica de Terrassa, encaminada a l’aplicacióde la Biotecnologia per desenvolupar nous sistemes enzimàtics per al blanqueig depastes i modificació de fibres cel·lulòsiques. La implantació d’etapes enzimàtiques en les seqüències de blanqueig de pasta de paper a nivell industrial continua essent, avui en dia, un dels principals reptes en el camp de la investigació paperera. La reducció de l’impacte ambiental, l’optimització de costos, així com el desenvolupament de productes paperers amb propietats noves i millorades, justifiquen l’estudi de noves seqüències enzimàtiques basades en l’aplicació de sistemes lacasa-mediador. La utilització d’una matèria prima renovable, el kenaf, està en sintonia amb el creixent interès de l’ús de fibres no fusteres per a l’obtenció de nous productes lignocel·lulòsics d’alt valor afegit. Així doncs, aquesta tesi es fonamenta en l’ús d’enzims per a blanquejar pasta de kenaf. Les seqüències de blanqueig enzimàtic estudiades consten de diferents tractaments amb el sistema lacasa-mediador (Etapa L). Les lacases utilitzades en aquesta etapa provenen dels fongs Pycnoporus cinnabarinus i Trametes villosa, les quals s’apliquen amb diferents mediadors naturals (compostos fenòlics derivats de la lignina) i amb un mediador sintètic. L’etapa enzimàtica es completa amb diferents etapes de blanqueig químic (quelant, peròxid d’hidrogen i peròxid d’hidrogen pressuritzat). Al final de les seqüències s’obtenen, en funció del mediador utilitzat en l’etapa enzimàtica, fibres de kenaf amb un alt contingut de cel·lulosa i altes blancors. En aquest sentit, en el transcurs de l’experimentació s’ha constatat la importància de la naturalesa química del mediador, ja que els diferents radicals fenoxi formats en l’etapa enzimàtica determinen la capacitat oxidativa del sistema lacasa-mediador. Per altra banda, els resultats obtinguts remarquen el paper de la composició química de la lignina de kenaf en el procés enzimàtic. La capacitat oxidativa de la lacasa augmenta en presència de pasta de kenaf i la quantitat d’àcids hexenurònics presents en la mateixa limita el grau de blancor assolit en els diferents tractaments, encara que el resultat final es semblant o superior a una pasta TCF convencional. L’aplicació de xilanases després de l’etapa enzimàtica lacasa-mediador es mostra efectiva en l’eliminació d’aquests àcids, essent una possible via de millora als tractaments proposats en la present tesi.The present thesis has been performed in the research group CIPAGRAF (Grup de Recerca Paperer i Gràfic) of the Departament d'Enginyeria Tèxtil i Paperera at the Escola Tècnica Superior d'Enginyeries Industrial i Aeronàutica de Terrassa. One of the research topics of the group is the application of enzymes in pulp biobleaching processes and in the modification of cellulosic fibers. The implementation of enzymatic stages in paper pulp bleaching sequences is, at present, one of the main challenges of the research in the paper industry. The application of laccase-Mediator systems can lead to a reduction of environmental impact and to cost optimization, as well as to the development of paper-derived products with novel and improved properties. The use of a renewable raw material -kenaf- is in accordance with the growing interest in the utilization of non-wood fibers for the production of new high-added value lignocellulosic products. Consequently, the present thesis is based on the use of enzymes for kenaf pulp bleaching. The enzymatic bleaching sequences studied involve different treatments with the laccase-Mediator system (Stage L). The two fungal enzymes used in this stage- Pycnoporus cinnabarinus and Trametes villosa laccases-have been assisted by different natural Mediators (lignin-derived phenolic compounds) and a synthetic one. The enzymatic stage has been completed with different chemical bleaching stages (chelating, hydrogen peroxide and pressurized hydrogen peroxide). At the end of the sequences, kenaf fibers with high cellulose levels and brightness were obtained. The significance of the chemical nature of the Mediator has been emphasized because the different phenoxy radicals formed in the enzymatic stage determine the oxidative capacity of the laccase-Mediator system. In addition, the results obtained also show the role of the chemical composition of kenaf lignin in the enzymatic process. The laccase oxidative capacity increases in the presence of kenaf pulp, and the amount of hexenuronic acids present limits the degree of brightness. Nevertheless, for the enzymatic treatments, the final results are similar to or better than for a conventional chlorine-free treatment. The application of xilanases after the laccase-Mediator stage has been shown to be efficient in hexenuronic acids removal, opening possible new improvements to the treatments reported in this work.Award-winningPostprint (published version
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Blanqueig enzimàtic de pasta de kenaf emprant sistemes lacasa-mediador
Universitat Politècnica de Catalunya, 2013Co-Authors: Andreu Terrén GlòriaAbstract:La present tesi s’emmarca dins d’una de les línies del Grup de Recerca Paperer i Gràfic (CIPAGRAF), del Departament d’Enginyeria Tèxtil i Paperera de l’Escola Tècnica Superior d’Enginyeries Industrial i Aeronàutica de Terrassa, encaminada a l’aplicacióde la Biotecnologia per desenvolupar nous sistemes enzimàtics per al blanqueig depastes i modificació de fibres cel·lulòsiques. La implantació d’etapes enzimàtiques en les seqüències de blanqueig de pasta de paper a nivell industrial continua essent, avui en dia, un dels principals reptes en el camp de la investigació paperera. La reducció de l’impacte ambiental, l’optimització de costos, així com el desenvolupament de productes paperers amb propietats noves i millorades, justifiquen l’estudi de noves seqüències enzimàtiques basades en l’aplicació de sistemes lacasa-mediador. La utilització d’una matèria prima renovable, el kenaf, està en sintonia amb el creixent interès de l’ús de fibres no fusteres per a l’obtenció de nous productes lignocel·lulòsics d’alt valor afegit. Així doncs, aquesta tesi es fonamenta en l’ús d’enzims per a blanquejar pasta de kenaf. Les seqüències de blanqueig enzimàtic estudiades consten de diferents tractaments amb el sistema lacasa-mediador (Etapa L). Les lacases utilitzades en aquesta etapa provenen dels fongs Pycnoporus cinnabarinus i Trametes villosa, les quals s’apliquen amb diferents mediadors naturals (compostos fenòlics derivats de la lignina) i amb un mediador sintètic. L’etapa enzimàtica es completa amb diferents etapes de blanqueig químic (quelant, peròxid d’hidrogen i peròxid d’hidrogen pressuritzat). Al final de les seqüències s’obtenen, en funció del mediador utilitzat en l’etapa enzimàtica, fibres de kenaf amb un alt contingut de cel·lulosa i altes blancors. En aquest sentit, en el transcurs de l’experimentació s’ha constatat la importància de la naturalesa química del mediador, ja que els diferents radicals fenoxi formats en l’etapa enzimàtica determinen la capacitat oxidativa del sistema lacasa-mediador. Per altra banda, els resultats obtinguts remarquen el paper de la composició química de la lignina de kenaf en el procés enzimàtic. La capacitat oxidativa de la lacasa augmenta en presència de pasta de kenaf i la quantitat d’àcids hexenurònics presents en la mateixa limita el grau de blancor assolit en els diferents tractaments, encara que el resultat final es semblant o superior a una pasta TCF convencional. L’aplicació de xilanases després de l’etapa enzimàtica lacasa-mediador es mostra efectiva en l’eliminació d’aquests àcids, essent una possible via de millora als tractaments proposats en la present tesi.The present thesis has been performed in the research group CIPAGRAF (Grup de Recerca Paperer i Gràfic) of the Departament d'Enginyeria Tèxtil i Paperera at the Escola Tècnica Superior d'Enginyeries Industrial i Aeronàutica de Terrassa. One of the research topics of the group is the application of enzymes in pulp biobleaching processes and in the modification of cellulosic fibers. The implementation of enzymatic stages in paper pulp bleaching sequences is, at present, one of the main challenges of the research in the paper industry. The application of laccase-Mediator systems can lead to a reduction of environmental impact and to cost optimization, as well as to the development of paper-derived products with novel and improved properties. The use of a renewable raw material -kenaf- is in accordance with the growing interest in the utilization of non-wood fibers for the production of new high-added value lignocellulosic products. Consequently, the present thesis is based on the use of enzymes for kenaf pulp bleaching. The enzymatic bleaching sequences studied involve different treatments with the laccase-Mediator system (Stage L). The two fungal enzymes used in this stage- Pycnoporus cinnabarinus and Trametes villosa laccases-have been assisted by different natural Mediators (lignin-derived phenolic compounds) and a synthetic one. The enzymatic stage has been completed with different chemical bleaching stages (chelating, hydrogen peroxide and pressurized hydrogen peroxide). At the end of the sequences, kenaf fibers with high cellulose levels and brightness were obtained. The significance of the chemical nature of the Mediator has been emphasized because the different phenoxy radicals formed in the enzymatic stage determine the oxidative capacity of the laccase-Mediator system. In addition, the results obtained also show the role of the chemical composition of kenaf lignin in the enzymatic process. The laccase oxidative capacity increases in the presence of kenaf pulp, and the amount of hexenuronic acids present limits the degree of brightness. Nevertheless, for the enzymatic treatments, the final results are similar to or better than for a conventional chlorine-free treatment. The application of xilanases after the laccase-Mediator stage has been shown to be efficient in hexenuronic acids removal, opening possible new improvements to the treatments reported in this work
John J B Allen - One of the best experts on this subject based on the ideXlab platform.
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frontal eeg asymmetry as a moderator and Mediator of emotion
Biological Psychology, 2004Co-Authors: James A Coan, John J B AllenAbstract:Frontal EEG asymmetry appears to serve as (1) an individual difference variable related to emotional responding and emotional disorders, and (2) a state-dependent concomitant of emotional responding. Such findings, highlighted in this review, suggest that frontal EEG asymmetry may serve as both a moderator and a Mediator of emotion- and motivation-related constructs. Unequivocal evidence supporting frontal EEG asymmetry as a moderator and/or Mediator of emotion is lacking, as insufficient attention has been given to analyzing the frontal EEG asymmetries in terms of moderators and Mediators. The present report reviews the frontal EEG asymmetry literature from the framework of moderators and Mediators, and overviews data analytic strategies that would support claims of moderation and mediation.
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frontal eeg asymmetry as a moderator and Mediator of emotion
Biological Psychology, 2004Co-Authors: James A Coan, John J B AllenAbstract:Frontal EEG asymmetry appears to serve as (1) an individual difference variable related to emotional responding and emotional disorders, and (2) a state-dependent concomitant of emotional responding. Such findings, highlighted in this review, suggest that frontal EEG asymmetry may serve as both a moderator and a Mediator of emotion- and motivation-related constructs. Unequivocal evidence supporting frontal EEG asymmetry as a moderator and/or Mediator of emotion is lacking, as insufficient attention has been given to analyzing the frontal EEG asymmetries in terms of moderators and Mediators. The present report reviews the frontal EEG asymmetry literature from the framework of moderators and Mediators, and overviews data analytic strategies that would support claims of moderation and mediation.
Maik Drechsler - One of the best experts on this subject based on the ideXlab platform.
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resolving lipid Mediators maresin 1 and resolvin d2 prevent atheroprogression in mice
Circulation Research, 2016Co-Authors: Joana R Viola, Patricia Lemnitzer, Yvonne Jansen, Gergely Csaba, Carla Winter, Carlos Neideck, Carlos Silvestreroig, Gunnar Dittmar, Yvonne Doring, Maik DrechslerAbstract:Rationale: Atheroprogression is a consequence of non-resolved inflammation and currently a comprehensive overview of the mechanisms preventing resolution is missing. However, in acute inflammation, resolution is known to be orchestrated by a switch from inflammatory to resolving lipid Mediators. Therefore we hypothesized that lesional lipid Mediator imbalance favors atheroprogression. Objective: To understand the lipid Mediator balance during atheroprogression and to establish an interventional strategy based on delivery of resolving lipid Mediators. Methods and Results: Aortic lipid Mediator profiling of aortas from Apoe -/- mice fed a high fat diet for four weeks, eight weeks, or four months revealed an expansion of inflammatory lipid Mediators, Leukotriene B4 (LTB4) and Prostaglandin E2 (PGE2), and a concomitant decrease of resolving lipid Mediators, Resolvin D2 (RvD2) and Maresin 1 (MaR1), during advanced atherosclerosis. Functionally, aortic LTB4 and PGE2 levels correlated with traits of plaque instability while RvD2 and MaR1 levels correlated with signs of plaque stability. In a therapeutic context, repetitive RvD2 and MaR1 delivery prevented atheroprogression as characterized by halted expansion of the necrotic core and accumulation of macrophages along with increased fibrous cap thickness and smooth muscle cell numbers. Mechanistically, RvD2 and MaR1 induced a shift in macrophage profile towards a reparative phenotype which secondarily stimulated collagen synthesis in smooth muscle cells. Conclusions: We present evidence for the imbalance between inflammatory and resolving lipid Mediators during atheroprogression. Delivery of RvD2 and MaR1 successfully prevented atheroprogression suggesting that resolving lipid Mediators potentially represent an innovative strategy to resolve arterial inflammation.
