TY - JOUR A1 - Sagu Tchewonpi, Sorel A1 - Zimmermann, Lynn A1 - Landgräber, Eva A1 - Homann, Thomas A1 - Huschek, Gerd A1 - Özpinar, Haydar A1 - Schweigert, Florian J. A1 - Rawel, Harshadrai Manilal T1 - Comprehensive Characterization and Relative Quantification of α-Amylase/Trypsin Inhibitors from Wheat Cultivars by Targeted HPLC-MS/MS JF - Foods N2 - The α-amylase/trypsin inhibitors (ATIs) are discussed as being responsible for non-celiac wheat sensitivity (NCWS), besides being known as allergenic components for baker’s asthma. Different approaches for characterization and quantification including proteomics-based methods for wheat ATIs have been documented. In these studies generally the major ATIs have been addressed. The challenge of current study was then to develop a more comprehensive workflow encompassing all reviewed wheat-ATI entries in UniProt database. To substantially test proof of concept, 46 German and Turkish wheat samples were used. Two extractions systems based on chloroform/methanol mixture (CM) and under buffered denaturing conditions were evaluated. Three aspects were optimized, tryptic digestion, chromatographic separation, and targeted tandem mass spectrometric analysis (HPLC-MS/MS). Preliminary characterization with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) documented the purity of the extracted ATIs with CM mixture and the amylase (60–80%)/trypsin (10–20%) inhibition demonstrated the bifunctional activity of ATIs. Thirteen (individual/common) biomarkers were established. Major ATIs (7–34%) were differently represented in samples. Finally, to our knowledge, the proposed HPLC-MS/MS method allowed for the first time so far the analysis of all 14 reviewed wheat ATI entries reported. KW - α-amylase/trypsin inhibitors KW - wheat cultivars KW - SDS-PAGE KW - peptides markers KW - relative quantification KW - mass spectrometry KW - LC-MRM-MS Y1 - 2020 U6 - https://doi.org/10.3390/foods9101448 SN - 2304-8158 VL - 9 IS - 10 PB - MDPI CY - Basel ER - TY - GEN A1 - Sagu Tchewonpi, Sorel A1 - Zimmermann, Lynn A1 - Landgräber, Eva A1 - Homann, Thomas A1 - Huschek, Gerd A1 - Özpinar, Haydar A1 - Schweigert, Florian J. A1 - Rawel, Harshadrai Manilal T1 - Comprehensive Characterization and Relative Quantification of α-Amylase/Trypsin Inhibitors from Wheat Cultivars by Targeted HPLC-MS/MS T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The α-amylase/trypsin inhibitors (ATIs) are discussed as being responsible for non-celiac wheat sensitivity (NCWS), besides being known as allergenic components for baker’s asthma. Different approaches for characterization and quantification including proteomics-based methods for wheat ATIs have been documented. In these studies generally the major ATIs have been addressed. The challenge of current study was then to develop a more comprehensive workflow encompassing all reviewed wheat-ATI entries in UniProt database. To substantially test proof of concept, 46 German and Turkish wheat samples were used. Two extractions systems based on chloroform/methanol mixture (CM) and under buffered denaturing conditions were evaluated. Three aspects were optimized, tryptic digestion, chromatographic separation, and targeted tandem mass spectrometric analysis (HPLC-MS/MS). Preliminary characterization with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) documented the purity of the extracted ATIs with CM mixture and the amylase (60–80%)/trypsin (10–20%) inhibition demonstrated the bifunctional activity of ATIs. Thirteen (individual/common) biomarkers were established. Major ATIs (7–34%) were differently represented in samples. Finally, to our knowledge, the proposed HPLC-MS/MS method allowed for the first time so far the analysis of all 14 reviewed wheat ATI entries reported. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1028 KW - α-amylase/trypsin inhibitors KW - wheat cultivars KW - SDS-PAGE KW - peptides markers KW - relative quantification KW - mass spectrometry KW - LC-MRM-MS Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-486118 SN - 1866-8372 IS - 1028 ER - TY - JOUR A1 - Zurell, Damaris A1 - Grimm, Volker A1 - Rossmanith, Eva A1 - Zbinden, Niklaus A1 - Zimmermann, Niklaus E. A1 - Schröder-Esselbach, Boris T1 - Uncertainty in predictions of range dynamics black grouse climbing the Swiss Alps JF - Ecography : pattern and diversity in ecology ; research papers forum N2 - Empirical species distribution models (SDMs) constitute often the tool of choice for the assessment of rapid climate change effects on species vulnerability. Conclusions regarding extinction risks might be misleading, however, because SDMs do not explicitly incorporate dispersal or other demographic processes. Here, we supplement SDMs with a dynamic population model 1) to predict climate-induced range dynamics for black grouse in Switzerland, 2) to compare direct and indirect measures of extinction risks, and 3) to quantify uncertainty in predictions as well as the sources of that uncertainty. To this end, we linked models of habitat suitability to a spatially explicit, individual-based model. In an extensive sensitivity analysis, we quantified uncertainty in various model outputs introduced by different SDM algorithms, by different climate scenarios and by demographic model parameters. Potentially suitable habitats were predicted to shift uphill and eastwards. By the end of the 21st century, abrupt habitat losses were predicted in the western Prealps for some climate scenarios. In contrast, population size and occupied area were primarily controlled by currently negative population growth and gradually declined from the beginning of the century across all climate scenarios and SDM algorithms. However, predictions of population dynamic features were highly variable across simulations. Results indicate that inferring extinction probabilities simply from the quantity of suitable habitat may underestimate extinction risks because this may ignore important interactions between life history traits and available habitat. Also, in dynamic range predictions uncertainty in SDM algorithms and climate scenarios can become secondary to uncertainty in dynamic model components. Our study emphasises the need for principal evaluation tools like sensitivity analysis in order to assess uncertainty and robustness in dynamic range predictions. A more direct benefit of such robustness analysis is an improved mechanistic understanding of dynamic species responses to climate change. Y1 - 2012 U6 - https://doi.org/10.1111/j.1600-0587.2011.07200.x SN - 0906-7590 VL - 35 IS - 7 SP - 590 EP - 603 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Kimminich, Eva A1 - Jäger, Heidi A1 - Horn-Conrad, Antje A1 - Scholz, Jana A1 - Zimmermann, Matthias A1 - Kampe, Heike T1 - Portal Wissen = Signs BT - The Research Magazine of the University of Potsdam N2 - Signs take a variety of forms. We use or encounter them every day in various areas. They represent perceptions and ideas: A letter represents a sound, a word or picture stands for an idea, a note for a sound, a chemical formula for a substance, a boundary stone for a territorial claim, a building for an ideology, a gesture for a cue or an assessment. On the one hand, we open up the world to ourselves by using signs; we acquire it, ensconce ourselves in it, and we punctuate it to represent ourselves in it. On the other, this reference to the world and ourselves becomes visible in our sign systems. As manifestations of a certain way of interacting with nature, the environment, and fellow human beings, they provide information about the social order or ethnic distinctions of a certain society or epoch as well as about how it perceives the world and humanity. As a man-made network of meanings, sign systems can be changed and, in doing so, change how we perceive the world and humanity. Linguistically, this may, for example, be done by using an evaluative prefix: human – inhuman, sense – nonsense, matter – anti-matter or by hierarchizing terms, as in upper class and lower class. The consequences of such labeling, therefore, may decide on the raison d'être of the signified within an aspect of reality and the nature of this existence. Since ancient times we have reflected on signs, at first mainly in philosophy. Each era has created theories of signs as a means of approaching its essence. Nowadays semiotics is especially concerned with them. While linguistics focuses on linguistic signs, semiotics deals with all types of signs and the interaction of components and processes involved in their communication. Semiotics has developed models, methods, and concepts. Semiosis and semiosphere, for example, are concepts that illuminate the processing of signs, i.e. the construction of meaning and the interaction of different sign systems. A sign is not limited to a monolithic meaning but is culturally contingent and marked by the socioeconomic conditions of the individual decoding it. Sociopolitical and sociocultural developments therefore affect the processing of signs. Dealing with signs and sign systems, their circulation, and reciprocal play with shapes and interpretive possibilities is therefore an urgent and trailblazing task in light of sociocultural communication processes in our increasingly heterogeneous society to optimize communication and promote intercultural understanding as well as to recognize, use, and bolster social trends. The articles in this magazine illustrate the many ways academia is involved in researching, interpreting, and explaining signs. Social scientists at the University of Potsdam are examining whether statistics about petitions made by GDR citizens can be interpreted retrospectively as a premonitory sign of the peaceful revolution of 1989. Colleagues at the Institute of Romance Studies are analyzing what Alexander von Humboldt’s American travel diaries signalize, and young researchers in the Research Training Group on “Wicked Problems, Contested Administrations” are examining challenges that seem to raise question marks for administrations. A project promoting sustainable consumption hopes to prove that academia can contribute to setting an example. An initiative of historians supporting Brandenburg cities in disseminating the history of the Reformation shows that the gap between academia and signs and wonder is not unbridgeable. I wish you an inspiring read! Prof. Dr. Eva Kimminich Professor of Romance Cultural Studies T3 - Portal Wissen: The research magazine of the University of Potsdam [Englische Ausgabe] - 02/2015 Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-441553 SN - 2198-9974 IS - 02/2015 ER - TY - JOUR A1 - Apergi, Maria A1 - Zimmermann, Eva A1 - Weko, Silvia A1 - Lilliestam, Johan T1 - Is renewable energy technology trade more or less conflictive than other trade? JF - Energy policy N2 - Renewable energy changes the geopolitics of energy: whereas access to fossil fuel resources were key in the past, control over technology and industry will be key in the future. Consequently, different scholars have predicted that a growing focus on renewables will increase or decrease conflict in the energy sector, with no consensus on which is most likely. Here, we investigate the degree of conflict in renewable energy technology (RET) trade by analyzing data on 7041 trade conflicts 1995–2020, guided by two sets of theory-driven hypotheses. We show that RET trade is associated with more, longer, and more intense trade conflicts than other trade conflicts for 1995–2016. This supports the neorealist, geo-economic view of countries being willing to risk conflict to increase their share of a market rather than avoiding conflicts to increase the overall market size. It also contradicts the view that renewables will reduce conflict: at least in the past and regarding trade, it has increased rather than decreased conflict. For 2017–2020, this trend is reversed and RET trade became significantly less conflictive than other trade. Our findings imply that improved conflict-resolution institutions for RET are needed. We also suggest establishing specific institutions to govern trade in immature technologies. Y1 - 2023 U6 - https://doi.org/10.1016/j.enpol.2023.113538 SN - 0301-4215 SN - 1873-6777 VL - 177 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Zang, Arno A1 - Stephansson, Ove A1 - Stenberg, Leif A1 - Plenkers, Katrin A1 - von Specht, Sebastian A1 - Milkereit, Claus A1 - Schill, Eva A1 - Kwiatek, Grzegorz A1 - Dresen, Georg A1 - Zimmermann, Günter A1 - Dahm, Torsten A1 - Weber, Michael T1 - Hydraulic fracture monitoring in hard rock at 410 m depth with an advanced fluid-injection protocol and extensive sensor array JF - Geophysical journal international N2 - In this paper, an underground experiment at the Aspo Hard Rock Laboratory (HRL) is described. Main goal is optimizing geothermal heat exchange in crystalline rock mass at depth by multistage hydraulic fracturing with minimal impact on the environment, that is, seismic events. For this, three arrays with acoustic emission, microseismicity and electromagnetic sensors are installed mapping hydraulic fracture initiation and growth. Fractures are driven by three different water injection schemes (continuous, progressive and pulse pressurization). After a brief review of hydraulic fracture operations in crystalline rock mass at mine scale, the site geology and the stress conditions at Aspo HRL are described. Then, the continuous, single-flow rate and alternative, multiple-flow rate fracture breakdown tests in a horizontal borehole at depth level 410 m are described together with the monitoring networks and sensitivity. Monitoring results include the primary catalogue of acoustic emission hypocentres obtained from four hydraulic fractures with the in situ trigger and localizing network. The continuous versus alternative water injection schemes are discussed in terms of the fracture breakdown pressure, the fracture pattern from impression packer result and the monitoring at the arrays. An example of multistage hydraulic fracturing with several phases of opening and closing of fracture walls is evaluated using data from acoustic emissions, seismic broad-band recordings and electromagnetic signal response. Based on our limited amount of in situ tests (six) and evaluation of three tests in Avro granodiorite, in the multiple-flow rate test with progressively increasing target pressure, the acoustic emission activity starts at a later stage in the fracturing process compared to the conventional fracturing case with continuous water injection. In tendency, also the total number and magnitude of acoustic events are found to be smaller in the progressive treatment with frequent phases of depressurization. KW - Geomechanics KW - Fracture and flow KW - Broad-band seismometers Y1 - 2016 SN - 0956-540X SN - 1365-246X VL - 208 SP - 790 EP - 813 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Günther, Oliver A1 - Schüle, Manja A1 - Zurell, Damaris A1 - Jeltsch, Florian A1 - Roeleke, Manuel A1 - Kampe, Heike A1 - Zimmermann, Matthias A1 - Scholz, Jana A1 - Engbert, Ralf A1 - Elsner, Birgit A1 - Schlangen, David A1 - Agrofylax, Luisa A1 - Georgi, Doreen A1 - Weymar, Mathias A1 - Wagener, Thorsten A1 - Bookhagen, Bodo A1 - Eibl, Eva P. S. A1 - Korup, Oliver A1 - Oswald, Sascha A1 - Thieken, Annegret A1 - van der Beek, Pieter A. T1 - Portal Wissen = Exzellenz JF - Portal Wissen: Das Forschungsmagazin der Universität Potsdam N2 - Was nicht nur gut oder sehr gut ist, nennen wir gern exzellent. Aber was meint das eigentlich? Vom lateinischen „excellere“ kommend, beschreibt es Dinge, Personen oder Handlungen, die „hervor-“ oder „herausragen“ aus der Menge, sich „auszeichnen“ gegenüber anderen. Mehr geht nicht. Exzellenz ist das Mittel der Wahl, wenn es darum geht, der Erste oder Beste zu sein. Und das macht auch vor der Forschung nicht halt. Wer auf die Universität Potsdam schaut, findet zahlreiche ausgezeichnete Forschende, hervorragende Projekte und immer wieder auch aufsehenerregende Erkenntnisse, Veröffentlichungen und Ergebnisse. Aber ist die UP auch exzellent? Eine Frage, die 2023 ganz sicher andere Wellen schlägt als vielleicht vor 20 Jahren. Denn seit dem Start der Exzellenzinitiative 2005 gelten als – wörtlich – exzellent jene Hochschulen, denen es gelingt, in dem umfangreichsten Förderprogramm für Wissenschaft in Deutschland einen Zuschlag zu erhalten. Egal ob in Form von Graduiertenschulen, Forschungsclustern oder – seit Fortsetzung des Programms ab 2019 unter dem Titel „Exzellenzstrategie“ – ganzen Exzellenzuniversitäten: Wer im Kreis der Forschungsuniversitäten zu den Besten gehören will, braucht das Siegel der Exzellenz. In der gerade eingeläuteten neuen Wettbewerbsrunde der „Exzellenzstrategie des Bundes und der Länder“ bewirbt sich die Universität Potsdam mit drei Clusterskizzen um Förderung. Ein Antrag kommt aus der Ökologie- und Biodiversitätsforschung. Ziel ist es, ein komplexes Bild ökologischer Prozesse zu zeichnen – und dabei die Rolle von einzelnen Individuen ebenso zu betrachten wie das Zusammenwirken vieler Arten in einem Ökosystem, um die Funktion der Artenvielfalt genauer zu bestimmen. Eine zweite Skizze haben die Kognitionswissenschaften eingereicht. Hier soll das komplexe Nebeneinander von Sprache und Kognition, Entwicklung und Lernen sowie Motivation und Verhalten als dynamisches Miteinander erforscht werden – wobei auch mit den Erziehungswissenschaften kooperiert wird, um verknüpfte Lernund Bildungsprozesse stets mitzudenken. Der dritte Antrag aus den Geo- und Umweltwissenschaften nimmt extreme und besonders folgenschwere Naturgefahren und -prozesse wie Überschwemmungen und Dürren in den Blick. Die Forschenden untersuchen die Extremereignisse mit besonderem Fokus auf deren Wechselwirkung mit der Gesellschaft, um mit ihnen einhergehende Risiken und Schäden besser einschätzen sowie künftig rechtzeitig Maßnahmen einleiten zu können. „Alle drei Anträge zeichnen ein hervorragendes Bild unserer Leistungsfähigkeit“, betont der Präsident der Universität, Prof. Oliver Günther, Ph.D. „Die Skizzen dokumentieren eindrucksvoll unser Engagement, vorhandene Forschungsexzellenz sowie die Potenziale der Universität Potsdam insgesamt. Allein die Tatsache, dass sich drei schlagkräftige Konsortien in ganz unterschiedlichen Themenbereichen zusammengefunden haben, zeigt, dass wir auf unserem Weg in die Spitzengruppe der deutschen Universitäten einen guten Schritt vorangekommen sind.“ In diesem Heft schauen wir, was sich in und hinter diesen Anträgen verbirgt: Wir haben mit den Wissenschaftlerinnen und Wissenschaftlern gesprochen, die sie geschrieben haben, und sie gefragt, was sie sich vornehmen, sollten sie den Zuschlag erhalten und ein Cluster an die Universität holen. Wir haben aber auch auf die Forschung geschaut, die zu den Anträgen geführt hat und die schon länger das Profil der Universität prägt und ihr national wie international Anerkennung eingebracht hat. Wir stellen eine kleine Auswahl an Projekten, Methoden und Forschenden vor, um zu zeigen, warum in diesen Anträgen tatsächlich exzellente Forschung steckt! Übrigens: Auch „Exzellenz“ ist nicht das Ende der Fahnenstange. Immerhin lässt sich das Adjektiv exzellent sogar steigern. In diesem Sinne wünschen wir exzellentestes Vergnügen beim Lesen! T3 - Portal Wissen: Das Forschungsmagazin der Universität Potsdam [Deutsche Ausgabe] - 02/2023 Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-611440 SN - 2194-4245 IS - 02/2023 ER - TY - JOUR A1 - Garbusow, Maria A1 - Schad, Daniel A1 - Sommer, Christian A1 - Juenger, Elisabeth A1 - Sebold, Miriam A1 - Friedel, Eva A1 - Wendt, Jean A1 - Kathmann, Norbert A1 - Schlagenhauf, Florian A1 - Zimmermann, Ulrich S. A1 - Heinz, Andreas A1 - Huys, Quentin J. M. A1 - Rapp, Michael A. T1 - Pavlovian-to-instrumental transfer in alcohol dependence: a pilot study JF - Neuropsychobiology : international journal of experimental and clinical research in biological psychiatry, pharmacopsychiatry, Biological Psychology/Pharmacopsychology and Pharmacoelectroencephalography N2 - Background: Pavlovian processes are thought to play an important role in the development, maintenance and relapse of alcohol dependence, possibly by influencing and usurping ongoing thought and behavior. The influence of pavlovian stimuli on ongoing behavior is paradigmatically measured by pavlovian-to-instrumental transfer (PIT) tasks. These involve multiple stages and are complex. Whether increased PIT is involved in human alcohol dependence is uncertain. We therefore aimed to establish and validate a modified PIT paradigm that would be robust, consistent and tolerated by healthy controls as well as by patients suffering from alcohol dependence, and to explore whether alcohol dependence is associated with enhanced PIT. Methods: Thirty-two recently detoxified alcohol-dependent patients and 32 age- and gender-matched healthy controls performed a PIT task with instrumental go/no-go approach behaviors. The task involved both pavlovian stimuli associated with monetary rewards and losses, and images of drinks. Results: Both patients and healthy controls showed a robust and temporally stable PIT effect. Strengths of PIT effects to drug-related and monetary conditioned stimuli were highly correlated. Patients more frequently showed a PIT effect, and the effect was stronger in response to aversively conditioned CSs (conditioned suppression), but there was no group difference in response to appetitive CSs. Conclusion: The implementation of PIT has favorably robust properties in chronic alcohol-dependent patients and in healthy controls. It shows internal consistency between monetary and drug-related cues. The findings support an association of alcohol dependence with an increased propensity towards PIT. KW - Pavlovian-to-instrumental transfer KW - Alcohol dependence KW - Human Y1 - 2014 U6 - https://doi.org/10.1159/000363507 SN - 0302-282X SN - 1423-0224 VL - 70 IS - 2 SP - 111 EP - 121 PB - Karger CY - Basel ER - TY - JOUR A1 - Schad, Daniel A1 - Garbusow, Maria A1 - Friedel, Eva A1 - Sommer, Christian A1 - Sebold, Miriam A1 - Hägele, Claudia A1 - Bernhardt, Nadine A1 - Nebe, Stephan A1 - Kuitunen-Paul, Sören A1 - Liu, Shuyan A1 - Eichmann, Uta A1 - Beck, Anne A1 - Wittchen, Hans-Ulrich A1 - Walter, Henrik A1 - Sterzer, Philipp A1 - Zimmermann, Ulrich S. A1 - Smolka, Michael N. A1 - Schlagenhauf, Florian A1 - Huys, Quentin J. M. A1 - Heinz, Andreas A1 - Rapp, Michael A. T1 - Neural correlates of instrumental responding in the context of alcohol-related cues index disorder severity and relapse risk JF - European archives of psychiatry and clinical neuroscience : official organ of the German Society for Biological Psychiatry N2 - The influence of Pavlovian conditioned stimuli on ongoing behavior may contribute to explaining how alcohol cues stimulate drug seeking and intake. Using a Pavlovian-instrumental transfer task, we investigated the effects of alcohol-related cues on approach behavior (i.e., instrumental response behavior) and its neural correlates, and related both to the relapse after detoxification in alcohol-dependent patients. Thirty-one recently detoxified alcohol-dependent patients and 24 healthy controls underwent instrumental training, where approach or non-approach towards initially neutral stimuli was reinforced by monetary incentives. Approach behavior was tested during extinction with either alcohol-related or neutral stimuli (as Pavlovian cues) presented in the background during functional magnetic resonance imaging (fMRI). Patients were subsequently followed up for 6 months. We observed that alcohol-related background stimuli inhibited the approach behavior in detoxified alcohol-dependent patients (t = -3.86, p < .001), but not in healthy controls (t = -0.92, p = .36). This behavioral inhibition was associated with neural activation in the nucleus accumbens (NAcc) (t((30)) = 2.06, p < .05). Interestingly, both the effects were only present in subsequent abstainers, but not relapsers and in those with mild but not severe dependence. Our data show that alcohol-related cues can acquire inhibitory behavioral features typical of aversive stimuli despite being accompanied by a stronger NAcc activation, suggesting salience attribution. The fact that these findings are restricted to abstinence and milder illness suggests that they may be potential resilience factors. KW - Alcohol dependence KW - Human neuroimaging KW - Nucleus accumbens KW - Pavlovian-instrumental transfer KW - Relapse Y1 - 2018 U6 - https://doi.org/10.1007/s00406-017-0860-4 SN - 0940-1334 SN - 1433-8491 VL - 269 IS - 3 SP - 295 EP - 308 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Friedel, Eva A1 - Sebold, Miriam A1 - Kuitunen-Paul, Sören A1 - Nebe, Stephan A1 - Veer, Ilya M. A1 - Zimmermann, Ulrich S. A1 - Schlagenhauf, Florian A1 - Smolka, Michael N. A1 - Rapp, Michael A. A1 - Walter, Henrik A1 - Heinz, Andreas T1 - How Accumulated Real Life Stress Experience and Cognitive Speed Interact on Decision-Making Processes JF - Frontiers in human neuroscienc N2 - Rationale: Advances in neurocomputational modeling suggest that valuation systems for goal-directed (deliberative) on one side, and habitual (automatic) decision-making on the other side may rely on distinct computational strategies for reinforcement learning, namely model-free vs. model-based learning. As a key theoretical difference, the model-based system strongly demands cognitive functions to plan actions prospectively based on an internal cognitive model of the environment, whereas valuation in the model-free system relies on rather simple learning rules from operant conditioning to retrospectively associate actions with their outcomes and is thus cognitively less demanding. Acute stress reactivity is known to impair model-based but not model-free choice behavior, with higher working memory capacity protecting the model-based system from acute stress. However, it is not clear which impact accumulated real life stress has on model-free and model-based decision systems and how this influence interacts with cognitive abilities. Methods: We used a sequential decision-making task distinguishing relative contributions of both learning strategies to choice behavior, the Social Readjustment Rating Scale questionnaire to assess accumulated real life stress, and the Digit Symbol Substitution Test to test cognitive speed in 95 healthy subjects. Results: Individuals reporting high stress exposure who had low cognitive speed showed reduced model-based but increased model-free behavioral control. In contrast, subjects exposed to accumulated real life stress with high cognitive speed displayed increased model-based performance but reduced model-free control. Conclusion: These findings suggest that accumulated real life stress exposure can enhance reliance on cognitive speed for model-based computations, which may ultimately protect the model-based system from the detrimental influences of accumulated real life stress. The combination of accumulated real life stress exposure and slower information processing capacities, however, might favor model-free strategies. Thus, the valence and preference of either system strongly depends on stressful experiences and individual cognitive capacities. KW - chronic stress KW - model-based learning KW - model-free learning KW - decision making KW - cognitive speed KW - real-life events Y1 - 2017 U6 - https://doi.org/10.3389/fnhum.2017.00302 SN - 1662-5161 VL - 11 SP - 1 EP - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Garbusow, Maria A1 - Schad, Daniel A1 - Sebold, Miriam A1 - Friedel, Eva A1 - Bernhardt, Nadine A1 - Koch, Stefan P. A1 - Steinacher, Bruno A1 - Kathmann, Norbert A1 - Geurts, Dirk E. M. A1 - Sommer, Christian A1 - Mueller, Dirk K. A1 - Nebe, Stephan A1 - Paul, Soeren A1 - Wittchen, Hans-Ulrich A1 - Zimmermann, Ulrich S. A1 - Walter, Henrik A1 - Smolka, Michael N. A1 - Sterzer, Philipp A1 - Rapp, Michael A. A1 - Huys, Quentin J. M. A1 - Schlagenhauf, Florian A1 - Heinz, Andreas T1 - Pavlovian-to-instrumental transfer effects in the nucleus accumbens relate to relapse in alcohol dependence JF - Addiction biology N2 - In detoxified alcohol-dependent patients, alcohol-related stimuli can promote relapse. However, to date, the mechanisms by which contextual stimuli promote relapse have not been elucidated in detail. One hypothesis is that such contextual stimuli directly stimulate the motivation to drink via associated brain regions like the ventral striatum and thus promote alcohol seeking, intake and relapse. Pavlovian-to-Instrumental-Transfer (PIT) may be one of those behavioral phenomena contributing to relapse, capturing how Pavlovian conditioned (contextual) cues determine instrumental behavior (e.g. alcohol seeking and intake). We used a PIT paradigm during functional magnetic resonance imaging to examine the effects of classically conditioned Pavlovian stimuli on instrumental choices in n=31 detoxified patients diagnosed with alcohol dependence and n=24 healthy controls matched for age and gender. Patients were followed up over a period of 3 months. We observed that (1) there was a significant behavioral PIT effect for all participants, which was significantly more pronounced in alcohol-dependent patients; (2) PIT was significantly associated with blood oxygen level-dependent (BOLD) signals in the nucleus accumbens (NAcc) in subsequent relapsers only; and (3) PIT-related NAcc activation was associated with, and predictive of, critical outcomes (amount of alcohol intake and relapse during a 3 months follow-up period) in alcohol-dependent patients. These observations show for the first time that PIT-related BOLD signals, as a measure of the influence of Pavlovian cues on instrumental behavior, predict alcohol intake and relapse in alcohol dependence. KW - human Pavlovian-to-instrumental transfer KW - nucleus accumbens KW - relapse in alcohol use disorder Y1 - 2016 U6 - https://doi.org/10.1111/adb.12243 SN - 1355-6215 SN - 1369-1600 VL - 21 SP - 719 EP - 731 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Günther, Oliver A1 - Schüle, Manja A1 - Zurell, Damaris A1 - Jeltsch, Florian A1 - Roeleke, Manuel A1 - Kampe, Heike A1 - Zimmermann, Matthias A1 - Scholz, Jana A1 - Mikulla, Stefanie A1 - Engbert, Ralf A1 - Elsner, Birgit A1 - Schlangen, David A1 - Agrofylax, Luisa A1 - Georgi, Doreen A1 - Weymar, Mathias A1 - Wagener, Thorsten A1 - Bookhagen, Bodo A1 - Eibl, Eva P. S. A1 - Korup, Oliver A1 - Oswald, Sascha A1 - Thieken, Annegret A1 - van der Beek, Pieter A. T1 - Portal Wissen = Excellence JF - Portal Wissen: The research magazine of the University of Potsdam N2 - When something is not just good or very good, we often call it excellent. But what does that really mean? Coming from the Latin word “excellere,” it describes things, persons, or actions that are outstanding or superior and distinguish themselves from others. It cannot get any better. Excellence is the top choice for being the first or the best. Research is no exception. At the university, you will find numerous exceptional researchers, outstanding projects, and, time and again, sensational findings, publications, and results. But is the University of Potsdam also excellent? A question that will certainly create a different stir in 2023 than it did perhaps 20 years ago. Since the launch of the Excellence Initiative in 2005, universities that succeed in winning the most comprehensive funding program for research in Germany have been considered – literally – excellent. Whether in the form of graduate schools, research clusters, or – since the program was continued in 2019 under the title “Excellence Strategy” – entire universities of excellence: Anyone who wants to be among the best research universities needs the seal of excellence. The University of Potsdam is applying for funding with three cluster proposals in the recently launched new round of the “Excellence Strategy of the German Federal and State Governments.” One proposal comes from ecology and biodiversity research. The aim is to paint a comprehensive picture of ecological processes by examining the role of single individuals as well as the interactions among many species in an ecosystem to precisely determine the function of biodiversity. A second proposal has been submitted by the cognitive sciences. Here, the complex coexistence of language and cognition, development and learning, as well as motivation and behavior will be researched as a dynamic interrelation. The projects will include cooperation with the educational sciences to constantly consider linked learning and educational processes. The third proposal from the geo and environmental sciences concentrates on extreme and particularly devastating natural hazards and processes such as floods and droughts. The researchers examine these extreme events, focusing on their interaction with society, to be able to better assess the risks and damages they might involve and to initiate timely measures in the future. “All three proposals highlight the excellence of our performance,” emphasizes University President Prof. Oliver Günther, Ph.D. “The outlines impressively document our commitment, existing research excellence, and the potential of the University of Potsdam as a whole. The fact that three powerful consortia have come together in different subject areas shows that we have taken a good step forward on our way to becoming one of the top German universities.” In this issue, we are looking at what is in and behind these proposals: We talked to the researchers who wrote them. We asked them about their plans in case their proposals are successful and they bring a cluster of excellence to the university. But we also looked at the research that has led to the proposals, has long shaped the university’s profile, and earned it national and international recognition. We present a small selection of projects, methods, and researchers to illustrate why there really is excellent research in these proposals! By the way, “excellence” is also not the end of the flagpole. After all, the adjective “excellent” even has a comparative and a superlative. With this in mind, I wish you the most excellent pleasure reading this issue! T3 - Portal Wissen: The research magazine of the University of Potsdam [Englische Ausgabe] - 02/2023 Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-611456 SN - 2198-9974 IS - 02/2023 ER -