On the track of the brain's microstructure : myelin water imaging using quantitative MRI

Conventional quantitative magnetic resonance imaging (MRI), for example monoexponential determination of the relaxation times T1 and T2, is sensitive to the various pathologies of myelinated tissue in the brain. However, it gives relatively unspecific information about the underlying nature of the disease. A parameter that directly correlates with the integrity of the myelin sheath is the so-called myelin water fraction (MWF). Based on multi-component analysis of non-invasive quantitative MRI measurements, mapping of the MWF becomes feasible and proved to be useful for studying demyelination and remyelination processes in the course of multiple sclerosis (MS) and other myelin related pathologies. Common myelin water imaging techniques often suffer from a lack of volume coverage due to their 2D acquisition schemes. This thesis focuses on the development of new myelin water mapping procedures, especially on fast 3D MRI measurements that provide whole brain coverage. In chapter 2, an MWF mapping technique based on balanced steady-state free precession (bSSFP) sequences is introduced. An extended bSSFP signal equation, which is based on a two-pool water model describing brain tissue, is derived to determine typical multi-compartment parameters, including the MWF, of healthy subjects. Possible influences of magnetization transfer effects, infinite radiofrequency pulses and B0/B1 inhomogeneities are discussed extensively. Chapter 3 introduces a 3D acquisition scheme based on multi-gradient-echo (mGRE) pulse sequences that is applied for sampling multi-component T2* decays in the human brain of healthy volunteers and MS patients. Quantitative myelin water maps are generated based on analysis of T2* spectra. Chapter 4 discusses possible adaptations and modifications of the proposed procedure from chapter 3 when moving to higher main magnetic field strengths. The effects of B0 inhomogeneities on the data sets and possible correction methods are additionally covered in this part of the thesis. Finally, the crucial role of accurate B1 and B0 imaging and the influences on myelin water imaging are revisited in chapter 5. A solution to simultaneous mapping of B1 and B0 is presented that might help to overcome systematic error sources in MWF mapping in the future

Memory Bounded Open-Loop Planning in Large POMDPs using Thompson Sampling

State-of-the-art approaches to partially observable planning like POMCP are based on stochastic tree search. While these approaches are computationally efficient, they may still construct search trees of considerable size, which could limit the performance due to restricted memory resources. In this paper, we propose Partially Observable Stacked Thompson Sampling (POSTS), a memory bounded approach to open-loop planning in large POMDPs, which optimizes a fixed size stack of Thompson Sampling bandits. We empirically evaluate POSTS in four large benchmark problems and compare its performance with different tree-based approaches. We show that POSTS achieves competitive performance compared to tree-based open-loop planning and offers a performance-memory tradeoff, making it suitable for partially observable planning with highly restricted computational and memory resources.Comment: Presented at AAAI 201

Legitimation strategies in an emerging field: family firm succession consultancy in Germany

Finding a successor has become a severe challenge for family firms in Germany. As family firms are disproportionately concentrated in rural economies, succession has also become a considerable threat for peripheral regions and their labor markets. It therefore lies in the interest of regional stakeholders to help support family business continuity. One way to do this is by providing consulting services for family entrepreneurs, especially when searching for a family-external successor. Succession consultancy, however is still in its infancy. Applying the framework of the organizational field that centers on the concept of legitimacy, this paper examines the strategies consultants employ in order to get selected by family entrepreneurs in their succession process, as well as consultants’ strategies to match family firms with external successors. Based on expert interviews with succession consultants in the region of Upper Palatinate in Bavaria, we demonstrate the importance of geography and interpersonal linkages in establishing legitimacy in the early stages of field formation, when heterogeneous groups of actors offer their services without set rules or standards. Our content analysis sheds light on the variety of strategies based on trust, networked, and public reputation in order to gain legitimacy as consultants, depending on whether or not they can draw on existing relationships with family firms. We furthermore identify a discrepancy between these legitimation strategies and the actual ways that consultants use to match family firms with external successors. Here, regardless of their previous contact with family firms, geography plays a major role in constraining both consulting and succession: Family firms more readily accept local consultants, and the consultants also preferred to screen succession candidates through their regional networks due to the higher chances of successful succession when finding external successors from within the same region. Conceptually, our analysis contributes to institutional theory by carving out legitimacy-enhancing mechanisms in emerging organizational fields, and by demonstrating the crucial role of geography and interpersonal linkages for succession as well as field formation processes

Der Ökologische Landbau in Mittel- und Osteuropa –Länderberichte

Die für das Jahr 2022 beantragten und genehmigten weiteren 14 Berichte sind bis auf die Berichte zu Belarus und Slowakei erstellt. Nach Abschluss des Projektes Ende 2023 liegt nun ein umfassendes Bild des Bio-Marktes der Region vor, mit insgesamt 24 Länderberichten aus zwei Projektphasen. Mit den nun vorliegenden Länderberichten wurde ein Beitrag zur Erreichung des Gesamtzieles (Kapitel 1.2) erreicht. Eine Beschreibung der Angebots- und Nachfragesituation im Bio-Sektor ist erfolgt. Chancen und Risiken für Marktakteure wurden benannt. Das Projektziel, eine aktuelle und detaillierte Übersicht über den Öko-Sektor in den bisher bearbeiteten Ländern zu geben, wurde erreicht. Damit können nicht nur die im ersten Durchgang 2010/11 publizierten Länderberichte mit den dann neu erstellten Berichten einen Einblick zur Entwicklung des Bio-Sektors dieser Länder in den letzten 10 Jahren geben, sondern es wird auch der Entwicklung der Marktbeziehungen und Potentiale der ganzen Region Rechnung getragen. Insbesondere die teilweise schon erfolgte und ansonsten zunehmende wirtschaftliche Entwicklung der beschriebenen Länder eröffnet auch Absatzmöglichkeiten für Bioprodukte aus Deutschland in diese. Damit sind die nun vorliegenden Länderberichte nicht nur für deutsche Akteure, die überwiegend Rohwaren aus ökologischer Herkunft aus diesen Ländern beziehen wollen, interessant, sondern auch für Akteure, die nach Absatzkanälen suchen oder ihr Netzwerk im Ökosektor auch international stärken wollen.Um eine Verstetigung der Projektarbeit zu ermöglichen sowie die Sichtbarkeit weiter zu erhöhen wurde eine bereits vorgelegte Projektskizze weiter verfolgt, mit Projektpartnern diskutiert und konkretisiert. Diese Konzeption mit Budget, um die Berichte mit eigener Webpräsenz zeitgemäßer und dynamisch anpassbar zu veröffentlichen, wird als separates Dokument erstellt und eingesandt

"Orte, an denen man wachsen kann" - Empirische Rekonstruktionen von Sinnzuschreibungen im Zusammenhang mit der Eröffnung zweier norwegischer Gedenkstätten

Der vorliegende Artikel ist das Resultat eines kleinen interdisziplinären Projekts zu Geschichtsbewusstsein, in dem wir Verfahren und Denkweisen von "Memory Research" - selbst ein interdisziplinäres Unterfangen - und Gesprächsforschung als linguistische und soziologische Disziplin kombiniert haben. Basis für die empirische Arbeit waren Interviews mit BesucherInnen der Eröffnungszeremonien für das Center for Studies of Holocaust and Religious Minorities (HL-Zentrum) in Oslo und das Falstad-Zentrum nördlich von Trondheim, Gedenkstätte eines ehemaligen SS-Strafgefangenenlagers und Menschenrechtszentrum. Der Artikel ist gleichzeitig ein programmatischer Versuch zu zeigen, dass Geschichtsbewusstsein am verlässlichsten in der Rekonstruktion von konkreter sprachlicher Interaktion zugänglich wird. Im ersten Teil des Artikels beleuchten wir die öffentliche Erinnerungskultur im Zusammenhang mit dem Holocaust und der deutschen Besatzung in Norwegen und reflektieren über die Funktion von Erinnerungsstätten. Dieser Teil bildet den Rahmen für die folgenden mikroanalytischen Rekonstruktionen zweier Gesprächsausschnitte, in denen wir die Brechungen zwischen offizieller Erinnerungskultur und privaten Sinngebungsprozessen und Orientierungsbedürfnissen sichtbar machen.This article is the result of an interdisciplinary endeavor to study the topic of historical consciousness, in which theoretical and methodological approaches of memory research (an interdisciplinary discipline in itself) and conversation analysis (a discipline integrating sociological and linguistic concepts) are combined. The study was empirically based on interviews with visitors of the opening ceremonies for the Holocaust Centre in Oslo and the Falstad-Centre near Trondheim (a memorial site and human rights center). One of our aims in the article is to demonstrate that historical consciousness can best be traced in actual social interaction and how the conversation analytic approach can be employed to make it accessible. We begin the article by giving an overview of the public memory culture related to the Holocaust and the German occupation of Norway and by reflecting on the function of memorial sites. This part establishes the frame for the microanalytic reconstructions of two interview segments. Through our analysis, we try to shed light upon the interplay and tensions between official memory culture and individual orientations and interpretations

Pratique de l’apprentissage interculturel

La Norvège explore les moyens d’intégrer de nouveaux groupes minoritaires, ethniques ou religieux, dans une société traditionnellement plus homogène. L’éducation est une composante essentielle de cette démarche. Elle peut contribuer à créer une culture de respect mutuel et de valorisation de la diversité et du pluralisme. Mais comment l’enseignement et l’apprentissage peuvent-ils concrétiser ce souhait ? Quelles sont les méthodes pédagogiques propres à relever ce défi ? L’article décrit une approche innovante, celle de l’apprentissage conceptuel. Par, l’intermédiaire du « projet de glossaire interculturel », les futurs enseignants dialoguent avec des pairs venus d’autres pays, grâce auxquels ils apprennent à mieux connaître d’autres cultures, et à réfléchir à leur propre perception de la société et de la diversité. Après un bref aperçu de la situation de l’éducation interculturelle en Norvège, les auteurs présentent l’outil pédagogique et son application dans le cadre d’une coopération internationale.Norway is exploring ways of integrating new minority, ethnic and religious groups into a traditionally more homogeneous society. Education is an essential part of this process. It can help to create a culture of mutual respect and to enhance diversity and pluralism. But how can teaching and learning make this possible? Which specific teaching methods can meet this challenge? The article describes an innovative approach, that of conceptual learning. Using a ‘draft intercultural glossary’, prospective teachers can talk with peers from other countries, so that they can learn more about other cultures and reflect on their own perceptions of society and diversity. After a brief overview of the state of intercultural education in Norway, the authors present the teaching tool and its application within the framework of international cooperation.Noruega explora los medios de integrar a nuevos grupos minoritarios, étnicos o religiosos, en una sociedad tradicionalmente más homogénea. La educación es un componente esencial de este proceso. Puede contribuir a crear una cultura de respecto mutuo y de valorización de la diversidad y del pluralismo. Sin embargo, ¿cómo la enseñanza y el aprendizaje pueden concretizar este deseo ? ¿Cuáles son los métodos pedagógicos propios para ganar este desafío ? El artículo describe una aproximación innovadora, la del aprendizaje conceptual. Por medio del “proyecto de glosario intercultural”, los futuros docentes dialogan con unos colegas que proceden de otros países, y gracias a los cuales aprenden a conocer mejor a otras culturas y a reflexionar sobre su propia percepción de la sociedad y de la diversidad. Después de una breve exposición de la situación de la educación intercultural en Noruega, los autores presentan el instrumento pedagógico y su aplicación en el marco de una cooperación internacional

FOSTERING DEMOCRATIC PREPAREDNESS TO PREVENT GROUP FOCUSED ENMITY IN NORWEGIAN SCHOOLS

U ovom radu predstavljen je konceptualni okvir norveškog projekta kojemu je cilj suzbijanje rasizma, antisemitizma i drugih oblika neprijateljstava usmjerenih prema manjinskim skupinama, kroz obrazovanje u nižim razredima srednje škole. Projekt pod naslovom “Demokratskom spremnošću protiv rasizma i antisemtizma” (“Democratic preparedness against Racism and Anti-Semitism” – Dembra) kombinira elemente stručnog usavršavanja nastavnika i razvoj škola. U projektu se koristilo uvidima iz međunarodnih istraživanja o neprijateljstvu usmjerenom prema skupinama (Zick et.al 2008, 2011), prema kojima će ljudi koji se osjećaju marginalizirano, isključeno i lišeno mogućnosti u društvu najvjerojatnije zadržati negativne stavove o jednoj ili nekoliko manjinskih skupina. Predrasude prema manjinama, osjećaj ugroženosti njihovom blizinom i protudemokratski stavovi, čini se, idu ruku pod ruku. Posljedica toga je da se pristup prema prevenciji neprijateljstva usmjerenog prema manjinskim skupinama kroz obrazovanje fokusira na razvoj inkluzivnog školskog okruženja, kao i na poticanje kritičkog razmišljanja, raspravu i aktivno sudjelovanje u demokratskim i različitim okruženjima. Ovaj rad opisuje cjelokupni školski pristup primijenjen u projektu, kombinirajući fokus na nastavnu praksu, školsku upravu i kulturu, koji se moraju razvijati u pojedinačnom kontekstu svake škole. Temeljeno na ovim principima, u trogodišnjem projektu radilo se s učiteljima i voditeljima 11 norveških škola. U radu se mogu vidjeti konkretni primjeri kako su pojedine škole implementirale aktivnosti povezane s različitostima, predrasudama i negativnim stavovima prema određenim manjinama. Koristeći se povratnim informacijama dobivenim od učitelja, razmotrit ćemo pozitivan utjecaj koji je projekt ostvario na učitelje škola koje su sudjelovale u njemu.This article introduces the conceptual framework of a Norwegian project which sets out to counteract racism, anti-Semitism and other forms of group focused enmity trough education in lower secondary schools. The project with the title “Democratic preparedness against Racism and Anti-Semitism” (Dembra) combines elements of in-service teacher training and school development. Conceptually, it operationalized insights from international research on group focused enmity (Zick et.al 2008, 2011) according to which people who feel marginalized, disconnected and deprived from opportunities in society are most likely to hold negative attitudes about one or several minority groups. Prejudice against minorities, a sense of being threatened by their presence and anti- democratic attitudes seem to go hand in hand. As a consequence, the approach towards prevention of group focused enmity through education focuses on developing inclusive school environments, as well as fostering critical thinking, debate and active participation in democratic and diverse environments. The article describes the whole school approach applied in the project, combining a focus on classroom practice, school governance and culture, which need to be developed in the particular context of each school. Based on these principles, the three-year project has worked with teachers and school leaders from 11 Norwegian schools. The article gives concrete examples of how some of the participating schools implemented activities related to diversity, prejudice and negative attitudes towards certain minorities. Based on the feedback from the participating teachers we will discuss the project’s positive impact on the teachers and the participating schools

FOSTERING DEMOCRATIC PREPAREDNESS TO PREVENT GROUP FOCUSED ENMITY IN NORWEGIAN SCHOOLS

U ovom radu predstavljen je konceptualni okvir norveškog projekta kojemu je cilj suzbijanje rasizma, antisemitizma i drugih oblika neprijateljstava usmjerenih prema manjinskim skupinama, kroz obrazovanje u nižim razredima srednje škole. Projekt pod naslovom “Demokratskom spremnošću protiv rasizma i antisemtizma” (“Democratic preparedness against Racism and Anti-Semitism” – Dembra) kombinira elemente stručnog usavršavanja nastavnika i razvoj škola. U projektu se koristilo uvidima iz međunarodnih istraživanja o neprijateljstvu usmjerenom prema skupinama (Zick et.al 2008, 2011), prema kojima će ljudi koji se osjećaju marginalizirano, isključeno i lišeno mogućnosti u društvu najvjerojatnije zadržati negativne stavove o jednoj ili nekoliko manjinskih skupina. Predrasude prema manjinama, osjećaj ugroženosti njihovom blizinom i protudemokratski stavovi, čini se, idu ruku pod ruku. Posljedica toga je da se pristup prema prevenciji neprijateljstva usmjerenog prema manjinskim skupinama kroz obrazovanje fokusira na razvoj inkluzivnog školskog okruženja, kao i na poticanje kritičkog razmišljanja, raspravu i aktivno sudjelovanje u demokratskim i različitim okruženjima. Ovaj rad opisuje cjelokupni školski pristup primijenjen u projektu, kombinirajući fokus na nastavnu praksu, školsku upravu i kulturu, koji se moraju razvijati u pojedinačnom kontekstu svake škole. Temeljeno na ovim principima, u trogodišnjem projektu radilo se s učiteljima i voditeljima 11 norveških škola. U radu se mogu vidjeti konkretni primjeri kako su pojedine škole implementirale aktivnosti povezane s različitostima, predrasudama i negativnim stavovima prema određenim manjinama. Koristeći se povratnim informacijama dobivenim od učitelja, razmotrit ćemo pozitivan utjecaj koji je projekt ostvario na učitelje škola koje su sudjelovale u njemu.This article introduces the conceptual framework of a Norwegian project which sets out to counteract racism, anti-Semitism and other forms of group focused enmity trough education in lower secondary schools. The project with the title “Democratic preparedness against Racism and Anti-Semitism” (Dembra) combines elements of in-service teacher training and school development. Conceptually, it operationalized insights from international research on group focused enmity (Zick et.al 2008, 2011) according to which people who feel marginalized, disconnected and deprived from opportunities in society are most likely to hold negative attitudes about one or several minority groups. Prejudice against minorities, a sense of being threatened by their presence and anti- democratic attitudes seem to go hand in hand. As a consequence, the approach towards prevention of group focused enmity through education focuses on developing inclusive school environments, as well as fostering critical thinking, debate and active participation in democratic and diverse environments. The article describes the whole school approach applied in the project, combining a focus on classroom practice, school governance and culture, which need to be developed in the particular context of each school. Based on these principles, the three-year project has worked with teachers and school leaders from 11 Norwegian schools. The article gives concrete examples of how some of the participating schools implemented activities related to diversity, prejudice and negative attitudes towards certain minorities. Based on the feedback from the participating teachers we will discuss the project’s positive impact on the teachers and the participating schools

Die Gegenwart in der Vergangenheit: Gruppendiskussionen über den Zweiten Weltkrieg und den Holocaust in (Ost)Deutschland und Norwegen

'Im folgenden Beitrag geht es darum, historische Sinnbildungsprozesse durch ein kontrastierendes Verfahren sichtbar zu machen. Dazu werden mit Norwegen und Ostdeutschland eine westeuropäische und eine postsozialistische Gesellschaft verglichen. Dieser Vergleich schärft den Blick dafür, dass in der Gesellschaft der ehemals Besetzten wie auch der ehemaligen Besatzer inzwischen eine dritte bzw. vierte Generation herangewachsen ist, die sich tradierte nationale und familiäre Muster des Erinnerns und Tradierens von NS- und Besatzungsgeschichte unter dem Eindruck eines zusammenwachsenden Europas und den Deutungsangeboten einer 'globalisierten Erinnerung' aneignet.' (Autorenreferat)'By applying a contrasting method, the article investigates how meaning is given to the past. Eastern Germany and Norway, a post socialist society and a well established welfare state, are compared. This contrast highlights that in the society of the former occupier as well as in that of the former occupied, a third and fourth generation has grown up which adopts traditional patterns of commemoration in new ways: both national and family narratives are transformed by the dynamics of a unified Europe and a 'globalisation' of commemoration.' (author's abstract