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  1. Article ; Online: Effect of pH on the Properties of Hydrogels Cross-Linked via Dynamic Thia-Michael Addition Bonds.

    FitzSimons, Thomas M / Anslyn, Eric V / Rosales, Adrianne M

    ACS polymers Au

    2021  Volume 2, Issue 2, Page(s) 129–136

    Abstract: ... with a reversible thia-Michael addition reaction in aqueous buffer between pH 3 and pH 7. The rate constants of bond ...

    Abstract Hydrogels cross-linked with dynamic covalent bonds exhibit time-dependent properties, making them an advantageous platform for applications ranging from biomaterials to self-healing networks. However, the relationship between the cross-link exchange kinetics, material properties, and stability of these platforms is not fully understood, especially upon addition of external stimuli. In this work, pH was used as a handle to manipulate cross-link exchange kinetics and control the resulting hydrogel mechanics and stability in a physiologically relevant window. Poly(ethylene glycol)-based hydrogels were cross-linked with a reversible thia-Michael addition reaction in aqueous buffer between pH 3 and pH 7. The rate constants of bond exchange and equilibrium constants were determined for each pH value, and these data were correlated with the resulting mechanical profiles of the bulk hydrogels. With increasing pH, both the forward and the reverse rate constants increased, while the equilibrium constant decreased. These changes led to faster stress relaxation and less stiff hydrogels at more basic pH values. The elevated pH values also led to an increased mass loss and a faster rate of release of an encapsulated model bovine serum albumin fluorescent protein. The connection between the kinetics, mechanics, and molecular release profiles provides important insight into the structure-property relationships of dynamic covalent hydrogels, and this system offers a promising platform for controlled release between physiologically relevant pH values.
    Language English
    Publishing date 2021-12-28
    Publishing country United States
    Document type Journal Article
    ISSN 2694-2453
    ISSN (online) 2694-2453
    DOI 10.1021/acspolymersau.1c00049
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online ; E-Book: Zwangsstörungen im Kindes- und Jugendalter

    Simons, Michael

    (Klinische Psychologie und Psychotherapie bei Kindern, Jugendlichen und jungen Erwachsenen)

    2022  

    Author's details Michael Simons
    Series title Klinische Psychologie und Psychotherapie bei Kindern, Jugendlichen und jungen Erwachsenen
    Keywords Psychotherapie ; Diagnostik ; Erscheinungsbild ; Zwangsstörungen ; Kinder- und Jugendlichenpsychotherapie
    Language German
    Size 1 Online-Ressource (174 Seiten), Illustrationen
    Edition 1. Auflage
    Publisher Verlag W. Kohlhammer
    Publishing place Stuttgart
    Publishing country Germany
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    HBZ-ID HT021587025
    ISBN 978-3-17-038421-7 ; 978-3-17-038422-4 ; 9783170384200 ; 3-17-038421-X ; 3-17-038422-8 ; 3170384201
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  3. Article: Kommentar zum Beitrag von Dirk Simons und Michael Ebert

    Schildbach, Thomas / Ebert, Michael / Simons, Dirk

    Rechnungslegung und Kapitalmarktregulierung bei Unternehmensnetzwerken , p. 69-71

    2008  , Page(s) 69–71

    Author's details Thomas Schildbach
    Language German
    Publisher Verlagsgruppe Handelsblatt
    Publishing place Düsseldorf
    Document type Article
    Database ECONomics Information System

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  4. Book ; Online ; E-Book: Fibroblast growth factors

    Simons, Michael

    biology and clinical application : FGF biology and therapeutics

    2017  

    Author's details Michael Simons
    Keywords Fibroblast Growth Factors
    Language English
    Size 1 Online-Ressource (viii, 274 Seiten), Illustrationen
    Publisher World Scientific
    Publishing place New Jersey
    Publishing country United States
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    HBZ-ID HT019755372
    ISBN 978-981-3143-37-1 ; 9789813143364 ; 981-3143-37-1 ; 9813143363
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  5. Article ; Online: Investigations on the effect of amino acids on acrylamide, pyrazines, and Michael addition products in model systems.

    Koutsidis, Georgios / Simons, Sandra P J / Thong, Yeong H / Haldoupis, Yannis / Mojica-Lazaro, Jonas / Wedzicha, Bronislaw L / Mottram, Donald S

    Journal of agricultural and food chemistry

    2009  Volume 57, Issue 19, Page(s) 9011–9015

    Abstract: Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine-glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar ... ...

    Abstract Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine-glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar concentration to asparagine, increased the rate of acrylamide formation. The strong correlation between the unsubstituted pyrazine and acrylamide suggests the promotion of the formation of Maillard reaction intermediates, and in particular glyoxal, as the determining mode of action. At increased amino acid concentrations, diverse effects were observed. The initial rates of acrylamide formation remained high for valine, alanine, phenylalanine, tryptophan, glutamine, and leucine, while a significant mitigating effect, as evident from the acrylamide yields after 60 min of heating at 160 degrees C, was observed for proline, tryptophan, glycine, and cysteine. The secondary amine containing amino acids, proline and tryptophan, had the most profound mitigating effect on acrylamide after 60 min of heating. The relative importance of the competing effect of added amino acids for alpha-dicarbonyls and acrylamide-amino acid alkylation reactions is discussed and accompanied by data on the relative formation rates of selected amino acid-AA adducts.
    MeSH term(s) Acrylamide/analysis ; Acrylamide/chemical synthesis ; Acrylamide/chemistry ; Amino Acids/administration & dosage ; Amino Acids/chemistry ; Asparagine/chemistry ; Glucose/chemistry ; Glycine/pharmacology ; Hot Temperature ; Maillard Reaction ; Models, Chemical ; Pyrazines/analysis ; Pyrazines/chemical synthesis
    Chemical Substances Amino Acids ; Pyrazines ; Acrylamide (20R035KLCI) ; Asparagine (7006-34-0) ; Glucose (IY9XDZ35W2) ; Glycine (TE7660XO1C)
    Language English
    Publishing date 2009-10-14
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 241619-0
    ISSN 1520-5118 ; 0021-8561
    ISSN (online) 1520-5118
    ISSN 0021-8561
    DOI 10.1021/jf9014763
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Endothelial-to-mesenchymal transition: advances and controversies.

    Simons, Michael

    Current opinion in physiology

    2023  Volume 34

    Abstract: Endothelial-to-mesenchymal transition (EndMT) is a physiological process that is equally important during development and under certain pathological conditions in adult tissues. The last decade has witnessed a remarkable explosion of information about ... ...

    Abstract Endothelial-to-mesenchymal transition (EndMT) is a physiological process that is equally important during development and under certain pathological conditions in adult tissues. The last decade has witnessed a remarkable explosion of information about EndMT from molecular mechanisms responsible for its development to its role in various disease processes. The emerging picture is that of a complex set of interactions that underly pathophysiological basis of some of the most deadly and intractable diseases. This mini review brings together recent advances and attempts to present a unified view of this complex field.
    Language English
    Publishing date 2023-05-08
    Publishing country England
    Document type Journal Article
    ZDB-ID 2918626-2
    ISSN 2468-8673 ; 2468-8681
    ISSN (online) 2468-8673
    ISSN 2468-8681
    DOI 10.1016/j.cophys.2023.100678
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book ; Thesis: Wirksamkeit einer Hybridinstrumentierung im Vergleich zur rigiden Spondylodese im Bereich der Lendenwirbelsäule

    Simons, Raoul Marvin / Siewe, Jan Norbert / Michael, J.

    3-Jahres Ergebnisse einer prospektiv-randomisierten Studie

    2021  

    Institution Universitätsklinikum Köln / Klinik und Poliklinik für Orthopädie und Unfallchirurgie
    Author's details vorgelegt von Raoul Marvin Simons ; 1. Gutachter: Privatdozent Dr. med. J. Siewe, 2. Gutachter: Professor Dr. med. J. Michael ; aus der Klinik und Poliklinik für Orthopädie und Unfallchirurgie der Universität zu Köln
    Subject code 610
    Language German
    Size 78 Seiten, Illustrationen, Diagramme
    Publishing place Köln
    Publishing country Germany
    Document type Book ; Thesis
    Thesis / German Habilitation thesis Dissertation, Universität zu Köln, 2021
    HBZ-ID HT021188599
    Database Catalogue ZB MED Medicine, Health

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  8. Article ; Audio / Video: Investigations on the Effect of Amino Acids on Acrylamide, Pyrazines, and Michael Addition Products in Model Systems

    Koutsidis, Georgios / Simons, Sandra P.J / Thong, Yeong H / Haldoupis, Yannis / Mojica-Lazaro, Jonas / Wedzicha, Bronislaw L / Mottram, Donald S

    Journal of agricultural and food chemistry. 2009 Oct. 14, v. 57, no. 19

    2009  

    Abstract: Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine−glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar ... ...

    Abstract Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine−glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar concentration to asparagine, increased the rate of acrylamide formation. The strong correlation between the unsubstituted pyrazine and acrylamide suggests the promotion of the formation of Maillard reaction intermediates, and in particular glyoxal, as the determining mode of action. At increased amino acid concentrations, diverse effects were observed. The initial rates of acrylamide formation remained high for valine, alanine, phenylalanine, tryptophan, glutamine, and leucine, while a significant mitigating effect, as evident from the acrylamide yields after 60 min of heating at 160 °C, was observed for proline, tryptophan, glycine, and cysteine. The secondary amine containing amino acids, proline and tryptophan, had the most profound mitigating effect on acrylamide after 60 min of heating. The relative importance of the competing effect of added amino acids for α-dicarbonyls and acrylamide−amino acid alkylation reactions is discussed and accompanied by data on the relative formation rates of selected amino acid−AA adducts.
    Keywords water content ; asparagine ; glucose ; model food systems ; acrylamides ; pyrazines ; Maillard reaction ; Maillard reaction products ; amino acids ; chemical structure ; mechanism of action ; heat treatment ; temperature
    Language English
    Dates of publication 2009-1014
    Size p. 9011–9015.
    Document type Article ; Audio / Video
    ZDB-ID 241619-0
    ISSN 1520-5118 ; 0021-8561
    ISSN (online) 1520-5118
    ISSN 0021-8561
    DOI 10.1021/jf9014763
    Database NAL-Catalogue (AGRICOLA)

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  9. Article: Zwangsstörungen bei Kindern und Jugendlichen. Diagnostik und Behandlung

    Simons, Michael

    Die Psychotherapie

    2023  Volume 68, Issue 3, Page(s) 224–234

    Abstract: Zwangsstörungen bestehen aus Zwangsgedanken bzw. einem Unvollständigkeits- oder "Nicht-genau-richtig"-Erleben, Zwangsritualen und Vermeidungsverhalten. In der Diagnostik werden die wesentlichen Aspekte der Zwangsstörung erfasst. Sie umfasst zudem ein ... ...

    Title translation Obsessive-compulsive disorders in children and adolescents. Diagnostics and treatment
    Abstract Zwangsstörungen bestehen aus Zwangsgedanken bzw. einem Unvollständigkeits- oder "Nicht-genau-richtig"-Erleben, Zwangsritualen und Vermeidungsverhalten. In der Diagnostik werden die wesentlichen Aspekte der Zwangsstörung erfasst. Sie umfasst zudem ein strukturiertes Interview und eine Verhaltensanalyse. Empirische Wirksamkeitsnachweise liegen nur für die Kognitive Verhaltenstherapie (KVT) und die Gabe von selektiven Serotonin-Wiederaufnahmehemmern vor. Die wesentliche Intervention in der KVT ist die Exposition mit Reaktionsverhinderung. Diese folgt traditionell einem Habituationsrational oder in den letzten Jahren zunehmend dem Rational des Inhibitionslernens. Ergänzend können kognitive und metakognitive Interventionen erfolgen. Familienbezogene Interventionen dienen insbesondere dem Abbau der familiären Akkommodation. (c) The Author(s), under exclusive licence to Springer Medizin Verlag GmbH
    Keywords Adolescent Psychotherapy ; Behandlungsleitlinien ; Child Psychotherapy ; Cognitive Behavior Therapy ; Expositionstherapie ; Exposure Therapy ; Familientherapie ; Family Therapy ; Jugendlichenpsychotherapie ; Kinderpsychotherapie ; Kognitive Verhaltenstherapie ; Metacognition ; Metakognition ; Obsessive Compulsive Disorder ; Psychotherapeutic Techniques ; Psychotherapeutische Techniken ; Reaktionshemmung ; Response Inhibition ; Treatment Guidelines ; Zwangsstörung
    Language German
    Document type Article
    ISSN 2731-7161
    ISSN 2731-7161
    DOI 10.1007/s00278-023-00657-7
    Database PSYNDEX

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  10. Article ; Online: Metacognitive Awareness and the Subjective Experience of Remembering in Aphantasia.

    Siena, Michael J / Simons, Jon S

    Journal of cognitive neuroscience

    2024  , Page(s) 1–21

    Abstract: Individuals with aphantasia, a nonclinical condition typically characterized by mental imagery deficits, often report reduced episodic memory. However, findings have hitherto rested largely on subjective self-reports, with few studies experimentally ... ...

    Abstract Individuals with aphantasia, a nonclinical condition typically characterized by mental imagery deficits, often report reduced episodic memory. However, findings have hitherto rested largely on subjective self-reports, with few studies experimentally investigating both objective and subjective aspects of episodic memory in aphantasia. In this study, we tested both aspects of remembering in aphantasic individuals using a custom 3-D object and spatial memory task that manipulated visuospatial perspective, which is considered to be a key factor determining the subjective experience of remembering. Objective and subjective measures of memory performance were taken for both object and spatial memory features under different perspective conditions. Surprisingly, aphantasic participants were found to be unimpaired on all objective memory measures, including those for object memory features, despite reporting weaker overall mental imagery experience and lower subjective vividness ratings on the memory task. These results add to newly emerging evidence that aphantasia is a heterogenous condition, where some aphantasic individuals may lack metacognitive awareness of mental imagery rather than mental imagery itself. In addition, we found that both participant groups remembered object memory features with greater precision when encoded and retrieved in the first person versus third person, suggesting a first-person perspective might facilitate subjective memory reliving by enhancing the representational quality of scene contents.
    Language English
    Publishing date 2024-02-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1007410-7
    ISSN 1530-8898 ; 0898-929X ; 1096-8857
    ISSN (online) 1530-8898
    ISSN 0898-929X ; 1096-8857
    DOI 10.1162/jocn_a_02120
    Database MEDical Literature Analysis and Retrieval System OnLINE

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