Refine
Has Fulltext
- no (144) (remove)
Year of publication
- 2018 (144) (remove)
Document Type
- Doctoral Thesis (144) (remove)
Keywords
- Schulentwicklung (2)
- AG "Weser" Solidarność Leninwerft (1)
- Abschaffung (1)
- Akademiegeschichte (1)
- Akkermansia muciniphila (1)
- Aktuator (1)
- Alternatividentitäten (1)
- Alternativvarietäten (1)
- Bewegung und Sport (1)
- Bewertung (1)
Institute
- Institut für Biochemie und Biologie (20)
- Historisches Institut (18)
- Institut für Chemie (13)
- Öffentliches Recht (12)
- Institut für Physik und Astronomie (11)
- Institut für Ernährungswissenschaft (9)
- Bürgerliches Recht (8)
- Sozialwissenschaften (8)
- Wirtschaftswissenschaften (7)
- Department Psychologie (6)
Ärgerliche Wirtshäuser, ergötzliche Häfen, empfindsame Kerker: Räume und Emotionen bilden emotionale Topografien, mit deren Hilfe sich die Akteure die Welt als Lebenswelt ordnen und aneignen. Der Autor untersucht den Zusammenhang zwischen Bewegung in frühneuzeitlichen Räumen und der emotionalen Bewegtheit der Akteure. Er kommt zu dem Schluss, dass Emotionen und Räume dabei nicht nur passiv erlebt, sondern aktiv vollzogen werden. Denn es handelt sich bei beiden um wechselseitig verbundene Handlungsanweisungen, die in Regeln, Topoi und Vorstellungen münden. Die sich ergebenden Verflechtungen nehmen verschiedene Formen an, die in kulturell, sozial und individuell bedingten emotionalen Topografien kulminieren, also in Anordnungen von Räumen und zugehörigen Emotionen. In dieser Struktur liegen somit Erklärungen für das Verhalten der Akteure verborgen.
Zeigen und Verbergen
(2018)
Obwohl heutige Filme kaum mehr ohne Effekte auskommen, gelten digitale Visual Effects häufig als Störfaktor oder bloßes Spektakel. Nur selten werden althergebrachte Diskurse und Vorurteile hinterfragt und Visual Effects oft als lediglich ins Digitale transformierte Effekte gesehen.
Für einen neuen Zugang zu diesem bisher unterrepräsentierten Medienphänomen schlägt Katrin von Kap-herr die Betrachtung der digitalen Visual Effects unter einem Doppelgestus des gleichzeitigen Zeigens und Verbergens vor. Dies lässt eine neue Lesart der Visual Effects zutage treten, welche sich deutlich von den Strategien der analogen Vorgänger absetzt. Die Untersuchung schließt damit eine Lücke für eine deutschsprachige Leserschaft.
Neben der vorherrschenden Unternehmenskultur existieren innerhalb der Organisationen unterschiedliche Subkulturen. Eine solche Subkultur - die berufliche - ist im Kontext dieser Arbeit von Bedeutung. Ihr Einfluss auf das Individuum in Form einer sekundären Sozialisation fängt in der Regel noch vor dem Eintritt im Unternehmen an und kann je nach Dauer der Einflussnahme und Stärke der Unternehmens- und der Subkulturen unterschiedlich sein. Im Mittelpunkt des Buches steht die Untersuchung der Abhängigkeiten zwischen der beruflichen kulturellen Prägung der Mitarbeiter und dem Umgang mit Wissen im Unternehmenskontext. Das Buch bietet einen theoretischen Überblick über die relevanten Themenfelder, stellt die Entwicklung eines Modells der Interdependenzen zwischen Wissensmanagement, Unternehmenskultur und beruflicher Subkultur vor und diskutiert erste Ergebnisse zur empirischen Untersuchung der Interdependenzen sowie das hierzu entwickelte Instrument.
Welle der Konsumgesellschaft
(2018)
Wie beeinflussten sich Massenmedien und Massenkonsum im Frankreich der Nachkriegszeit gegenseitig?
Radio Luxembourg war in der europäischen Rundfunklandschaft der Nachkriegszeit eine Ausnahme: Die privatkommerzielle Radiostation sendete werbefinanzierte Unterhaltungsprogramme in die benachbarten Staaten und erreichte damit ein Millionenpublikum. Die Autorin Anna Jehle zeigt anhand verschiedener Untersuchungsfelder - der Unternehmens- und Programmgeschichte, der Zielgruppen, der Marketingaktivitäten und des Werbezeitenverkaufs -, wie eng die Entwicklung der Konsumgesellschaft im Frankreich der sogenannten trente glorieuses mit der Verbreitung und Nutzung des Radios verbunden war. Mit seinem ganz auf Massenkonsum ausgerichteten Rundfunkkonzept war Radio Luxembourg nicht nur integraler Bestandteil, sondern auch Katalysator und Agent der Konsummoderne. Dies hatte weitreichende Auswirkungen für das französische Rundfunksystem, das sich unter dem Einfluss Radio Luxembourgs kommerzialisierte, und zwar bereits lange vor der Deregulierung des Rundfunks in den 1980er Jahren.
Vom Neandertal nach Afrika
(2018)
Spektakuläre Debatten um bedeutende Fossilienfunde begleiteten die Suche nach unseren Ursprüngen.
Wer waren die ersten Menschen? Nachdem die Antwort darauf lange mit der Schöpfungsgeschichte verbunden war, entflammten ab Mitte des 19. Jahrhunderts neuartige Debatten. Funde menschlicher Fossilien führten zu Auseinandersetzungen über den Ursprung der Menschheit. Umkämpft war nicht nur die Frage, ob die ersten Menschen Deutsche, Engländer, Europäer oder Asiaten waren, ob schwarz oder weiß. Es ging um das Wesen des Menschen. Knochen aus dem Neandertal, von Java oder Südafrika bilden bis heute eine Projektionsfläche für das Verständnis des menschlichen Selbst. Entsprechend intensiv waren die internationalen wissenschaftlichen und öffentlichen Debatten, bis sich in den 1950er Jahren die Idee eines gemeinsamen afrikanischen Ursprungs durchsetzte.
Ellinor Schweighöfer geht am Beispiel spektakulärer Funde der Suche nach dem Ursprung nach. Sie untersucht, welche Zuschreibungen die Funde auslösten und mit welchen Techniken sich wissenschaftliche Fakten etablierten. Es ist eine Wissensgeschichte, bei der viele Stimmen einbezogen werden - Wissenschaftler ebenso wie Massenmedien. So macht die Autorin auch die Wechselwirkungen zwischen Weltanschauung, Politik und Wissenschaft deutlich.
Vom Kadetten bis zum Admiral
(2018)
Die Royal Navy und die Kaiserliche Marine erlebten seit dem letzten Drittel des 19. Jahrhunderts einen grundlegenden Wandel. Prägten anfangs Segelschiffhybride als Hauptkampfmittel die beiden Flotten, dominierten sie Großkampfschiffe vor Beginn des Ersten Weltkrieges. Aber auch U-Boote und Seeflugzeuge spielten eine zunehmende Rolle. Vor allem die drastischen technologischen und gesellschaftlichen Entwicklungen wirkten sich auf die Aufgaben, Rekrutierung und Ausbildung der Offiziere aus. Christian Jentzsch untersucht, wie das Seeoffizierkorps der Kaiserlichen Marine und das Executive Officer Corps der Royal Navy auf die Herausforderungen reagierten.
Den Inhalt eines Vertrags müssen die Parteien nicht selbst, sie können ihn kraft der ihnen zugewiesenen Privatautonomie durch einen Dritten vervollständigen oder anpassen lassen. Dieser Mechanismus lässt sich zu einer alternativen Streitbeilegungsmethode ausbauen, der »Vertragsarbitrage«. Der Begriff Vertragsarbitrage umfasst die in der Praxis weit verbreiteten »Schiedsgutachten« und »Dispute Adjudication Boards«, ist aber umfassender zu verstehen. Die Bezeichnung soll aufzeigen, dass neben der im Prozessrecht geregelten Schiedsgerichtsbarkeit eine im materiellem Recht verwurzelte alternative Streitbeilegungsmethode existiert, die ebenfalls zu verbindlichen Entscheidungen führt.
Über die Untersuchung des deutschen Rechts hinaus wird die Ausgestaltung von Vertragsarbitrageverfahren im englischen und französischem Recht untersucht. Die so nachgewiesenen Unterschiede der Rechtsordnungen führen zu der sodann untersuchten Frage des anwendbaren Rechts.
Through IOs' Eyes
(2018)
Is global governance characterized by overlap and fragmentation, or by coordination and harmonization? There are two rather different narratives about the worlds in which international organizations (IOs) live. One way or another, IOs are part of a broader environment and engage in relations with other actors in it. Rather than being detached from their environment, IOs are shaped by and respond to developments taking place within it (e.g., overlap). Thus, the general research interest of this dissertation lies in organizational responses to such environmental developments. Therein, the emphasis is placed on IO positionality, meaning the position of an IO within a “web” of interorganizational relations, or, more precisely, an IO’s position within an organizational field as a specification of the IO environment.
Against this background, the dissertation poses the following research question: How does an IO’s position within an organizational field shape its responses to developments of the field? In that, three subquestions are advanced: Which position does an IO occupy within the organizational field? How does an IO perceive the organizational field? How does an IO respond to developments and features of the field? Theoretically, the dissertation combines an open system perspective on IOs with two variants of field theory inspired by Bourdieu and by DiMaggio and Powell. Building on the central concept of the organizational field, the dissertation understands IOs as actors with agency. Empirically, the dissertation consists of a qualitative, comparative study and analyzes two IOs located within the organizational field of global food security governance. I select IOs that occupy different positions within the field of food security governance, namely an IO at the core of the field (the United Nations Food and Agriculture Organization, or FAO) and an IO at the periphery of the field (the United Nations Industrial Development Organization, or UNIDO). I compare and analyze their respective perceptions of the field of food security governance, including their own role and their understandings of food security, and their responses over time. To investigate these IOs’ perceptions and responses over time, the method of choice consists of a qualitative content analysis of a wide range of organizational documents (e.g., governing bodies’ reports).
The main argument this dissertation advances is as follows: The position that an IO occupies within an organizational field influences how the organization perceives its environment—in particular, features of and developments within this environment. Against this background, the main findings of this dissertation are as follows: Overall, FAO and UNIDO both perceive proliferation, overlap, and duplication as relevant developments of the organizational field of global food security governance over time. While both IOs see developments in the field of food security governance (e.g., overlap and duplication) as problematic given their detrimental effects for food security governance, FAO and UNIDO differ in decisive regards. Whereas FAO holds a narrative that other actors were responsible for this state of affairs, and thus responsible for reducing or even eliminating overlap and duplication, UNIDO perceives these developments differently. UNIDO acknowledges its own role in the development of overlap and duplication, and therefore also sees a role for itself in addressing these developments. The two IOs thus differ in what they understand to be the causes and historical priors of field-specific developments. Furthermore, while both FAO and UNIDO attempt to demonstrate that they are constructive players within the UN development system, the two IOs differ in their responses: While FAO engages in balancing by voicing its commitment to UN processes and to coordination, yet early on making different reservations, UNIDO, in contrast, engages in UN processes without similar reservations. Accordingly, the two IOs also differ on the responses they employ to field-level harmonization demands.
The dissertation makes several contributions. Theoretically, I contribute an innovative argument on the influence of perceptions for organizational responses to developments in the IOs’ environment. This argument may help us to better understand how IOs as actors embedded within an organizational field deal with changes evolving within these fields. Empirically, I scrutinize developments in food security governance, such as proliferation and overlap, through the eyes of IOs in the field. While proliferation, overlap, and duplication are often referred to in academic debates on food security governance, we do not yet actually understand these phenomena very well. To this, I contribute a study that analyzes IO perceptions of these developments in the field, thus resulting in a more in-depth and nuanced picture of how IOs perceive these developments as a central type of actor in food security governance. Next, to this emphasis on the IO perspective, I also inductively develop a spectrum of IO responses to field developments, ranging from expanding scope to defending turf. Finally, I also make a methodological-conceptual contribution: While concepts such as “position” are well-known, they are sometimes drawn on without developing a clear foundation of how to assess different positions. I thus add an approach for bringing this concept of position to life by developing a range of criteria that can be used to approximate an IO’s position within an organizational field, depending on different types of capital.
Systemic inflammation is a hallmark of cancer cachexia. Among tumor-host interactions, the white adipose tissue (WAT) is an important contributor to inflammation as it suffers morphological reorganization and lipolysis, releasing free fatty acids (FA), bioactive lipid mediators (LM) and pro-inflammatory cytokines, which accentuate the activation of pro-inflammatory signaling pathways and the recruitment of immune cells to the tissue. This project aimed to investigate which inflammatory factors are involved in the local adipose tissue inflammation and what is the influence of such factors upon enzymes involved in FA or LM metabolism in healthy individuals (Control), weight stable gastro-intestinal cancer patients (WSC) and cachectic cancer patients (CC). The results demonstrated that the inflammatory signature of systemic inflammation is different from local adipose tissue inflammation. The systemic inflammation of the cachectic cancer patients was characterized by higher levels of circulating saturated fatty acids (SFA), tumor-necrosis-factor-α (TNF-α), interleukins IL-6, IL-8 and CRP while levels of polyunsaturated fatty acids (PUFAs), especially n3-PUFAs, were lower in CC than in the other groups. In vitro and in adipose tissue explants, pro-inflammatory cytokines and SFAs were shown to increase the chemokines IL-8 and CXCL10 that were found to be augmented in adipose tissue inflammation in CC which was more profound in the visceral adipose tissue (VAT) than in subcutaneous adipose tissue (SAT). Systemic inflammation was negatively associated with the expression of PUFA synthesizing enzymes, though gene and protein expression did hardly differ between groups. The effects of inflammatory factors on enzymes in the whole tissue could have been masked by differentiated modulation of the diverse cell types in the same tissue. In vitro experiments showed that the expression of FA-modifying enzymes such as desaturases and elongases in adipocytes and macrophages was regulated into opposing directions by TNF-α, IL-6, LPS or palmitate. The higher plasma concentration of the pro-resolving LM resolvin D1 in CC cannot compensate the overall inflammatory status and the results indicate that inflammatory cytokines interfere with synthesis pathways of pro-resolving LM. In summary, the data revealed a complex inter-tissue and inter-cellular crosstalk mediated by pro-inflammatory cytokines and lipid compounds enhancing inflammation in cancer cachexia by feed-forward mechanisms.
Microbiota analyses of patients suffering from various diseases suggest a beneficial role of Akkermansia muciniphila in the maintenance of health, whereas several studies in animal models of intestinal inflammation report that this organism may aggravate inflammation. Therefore, it is important to clarify under which circumstances A. muciniphila exerts negative effects in the intestine of its host.
The previously reported observation that A. muciniphila aggravates acute intestinal inflammation in the Salmonella enterica serovar Typhimurium infection mouse model colonized with a simplified human intestinal microbiota was investigated in this study. To unravel the underlying mechanism that led to the observed phenomenon, the time course of events following the infection was analyzed. In mice colonized with a simplified human intestinal microbiota, Salmonella infection induced clear signs of intestinal inflammation three days post infection. The inflammatory response was similar in mice colonized with A. muciniphila before Salmonella infection. These observations were independent of the time when colonization with the simplified human intestinal microbiota occurred, right after birth or only after weaning, and contradict the previous report.
To find out whether A. muciniphila influences the development of chronic intestinal inflammation in a genetically predisposed host, mono-associated interleukin-10-deficient (Il10-/-) mice, Il10-/- mice dual-associated with A. muciniphila and colitogenic Escherichia coli NC101, as well as Il10-/- mice associated with A. muciniphila and a simplified human intestinal microbiota were compared to the respective mice without A. muciniphila. The data clearly show that in these gnotobiotic Il10-/- mice, A. muciniphila neither induces intestinal inflammation itself nor modulates it after induction by a colitogenic bacterium or by a simplified human intestinal microbiota.
The experiments lead to the conclusion that the promotion of intestinal inflammation is not an intrinsic feature of this bacterium. The results of this study encourage the proposed use of A. muciniphila for the prevention or treatment of metabolic disorders.
Terrain de je
(2018)
Synchrotron-based angle-resolved time-of-flight electron spectroscopy for dynamics in dichalogenides
(2018)
Der Autor entwickelt ein Modell des strategischen und operativen Managements in Konzernrechtsabteilungen und richtet dabei den Fokus auf praktische Erkenntnisse, die auf betriebs- und volkswirtschaftlichen Theorien sowie zahlreichen Experteninterviews aufgebaut sind. Ein besonderes Augenmerk legt er auf die Spezifika von Rechtsdienstleistungen im Vergleich zu anderen Leistungen, die in einem Konzern benötigt werden. Die Sichtweise des Leiters einer Rechtsabteilung /General Counsels steht dabei im Vordergrund. Es wird die Frage untersucht, wie dieser die Leitung und Steuerung der gesamten Abteilung am effizientesten und effektivsten ausfüllen kann.
Spectroscopy at the limit
(2018)
Shaping via binding
(2018)
The ongoing trend of miniaturizing multifunctional devices, especially for minimally-invasive medical or sensor applications demands new strategies for designing the required functional polymeric micro-components or micro-devices. Here, polymers, which are capable of active movement, when an external stimulus is applied (e.g. shape-memory polymers), are intensively discussed as promising material candidates for realization of multifunctional micro-components. In this context further research activities are needed to gain a better knowledge about the underlying working principles for functionalization of polymeric micro-scale objects with a shape-memory effect. First reports about electrospun solid microfiber scaffolds, demonstrated a much more pronounced shape-memory effect than their bulk counterparts, indicating the high potential of electrospun micro-objects.
Based on these initial findings this thesis was aimed at exploring whether the alteration of the geometry of micro-scale electrospun polymeric objects can serve as suitable parameter to tailor their shape-memory properties. The central hypothesis was that different geometries should result in different degrees of macromolecular chain orientation in the polymeric micro-scale objects, which will influence their mechanical properties as well as thermally-induced shape-memory function. As electrospun micro-scale objects, microfiber scaffolds composed of hollow microfibers with different wall thickness and electrosprayed microparticles as well as their magneto-sensitive nanocomposites all prepared from the same polymer exhibiting pronounced bulk shape-memory properties were investigated. For this work a thermoplastic multiblock copolymer, named PDC, with excellent bulk shape-memory properties, associated with crystallizable oligo(ε-caprolactone) (OCL) switching domains, was chosen for the preparation of electrospun micro-scale objects, while crystallizable oligo(p-dioxanone) (OPDO) segments serve as hard domains in PDC.
In the first part of the thesis microfiber scaffolds with different microfiber geometries (solid or hollow with different wall thickness) were discussed. Hollow microfiber based PDC scaffolds were prepared by coaxial electrospinning from a 1, 1, 1, 3, 3, 3 hexafluoro-2-propanol (HFP) solution with a polymer concentration of 13% w·v-1. Here as a first step core-shell fiber scaffolds consisting of microfibers with a PDC shell and sacrificial poly(ethylene glycol) (PEG) core are generated. The hollow PDC microfibers were achieved after dissolving the PEG core with water. The utilization of a fixed electrospinning setup and the same polymer concentration of the PDC spinning solution could ensure the fabrication of microfibers with almost identical outer diameters of 1.4 ± 0.3 µm as determined by scanning electron microscopy (SEM). Different hollow microfiber wall thicknesses of 0.5 ± 0.2 and 0.3 ± 0.2 µm (analyzed by SEM) have been realized by variation of the mass flow rate, while solid microfibers were obtained by coaxial electrospinning without supplying any core solution. Differential scanning calorimetry experiments and tensile tests at ambient temperature revealed an increase in degree of OCL crystallinity form χc,OCL = 34 ± 1% to 43 ± 1% and a decrease in elongation of break from 800 ± 40% to 200 ± 50% associated with an increase in Young´s modulus and failture stress for PDC hollow microfiber scaffolds when compared with soild fibers. The observed effects were enhanced with decreasing wall thickness of the single hollow fibers. The shape-memory properties of the electrospun PDC scaffolds were quantified by cyclic, thermomechanical tensile tests. Here, scaffolds comprising hollow microfibers exhibited lower shape fixity ratios around Rf = 82 ± 1% and higher shape recovery ratios of Rr = 67 ± 1% associated to more pronounced relaxation at constant strain during the first test cycle and a lower switching temperature of Tsw = 33 ± 1 °C than the fibrous meshes consisting of solid microfibers. These findings strongly support the central hypothesis that different fiber geometries (solid or hollow with different wall thickness) in electrospun scaffolds result in different degrees of macromolecular chain orientation in the polymeric micro-scale objects, which can be applied as design parameter for tailoring their mechanical and shape-memory properties.
The second part of the thesis deals with electrosprayed particulate PDC micro-scale objects. Almost spherical PDC microparticles with diameters of 3.9 ± 0.9 μm (as determined by SEM) were achieved by electrospraying of HFP solution with a polymer concentration of 2% w·v-1. In contrast, smaller particles with sizes of 400 ± 100 nm or 1.2 ± 0.3 μm were obtained for the magneto-sensitive composite PDC microparticles containing 23 ± 0.5 wt% superparamagnetic magnetite nanoparticles (mNPs). All prepared PDC microparticles exhibited a similar overall crystallinity like the PDC bulk material as analyzed by DSC. AFM nanoindentation results revealed no influence of the nanofiller incorporation on the local mechanical properties represented by the reduced modulus determined for pure PDC microparticles and magneto-sensitive composite PDC microparticles with similar diameters around 1.3 µm. It was found that the reduced modulus of the nanocomposite microparticles increased substantially with decreasing particles size from 2.4 ± 0.9 GPa (1.2 µm) to 11.9 ± 3.1 GPa (0.4 µm), which can be related to a higher orientation of the macromolecules at the surface of smaller sized microparticles. The magneto-sensitivity of such nanocomposite microparticles could be demonstrated in two aspects. One was by attracting/collecting the composite micro-objects with an external permanent magnet. The other one was by a inductive heating to 44 ± 1 °C, which is well above the melting transition of the OCL switching domains, when compacted to a 10 x 10 mm2 film with a thickness of 10 µm and exposed to an alternating magnet field with an magnetic field strength of 30 kA·m-1. Both functions are of great relevance for designing next generation drug delivery systems combining targeting and on demand release.
By a compression approach shape-memory functionalization of individual microparticles could be realized. Here different programming pressures and compression temperatures were applied. The shape-recovery capability of the programmed PDC microparticles was quantified by online and off-line heating experiments analyzed via microscopy measurement. The obtained shape-memory properties were found to be strongly depending on the applied programming pressure and temperature. The best shape-memory performance with a high shape recovery rate of about Rr = 80±1% was obtained when a low pressure of 0.2 MPa was applied at 55 °C. Finally, it was demonstrated that PDC microparticles can be utilized as micro building parts for preparation of a macroscopic film with temporary stability by compression of a densely packed array of PDC microparticles at 60 °C followed by subsequent cooling to ambient temperature. This film disintegrates into individual microparticles upon heating to 60 °C. Based on this technology the design of stable macroscopic release systems can be envisioned, which can be easily fixed at the site of treatment (i.e. by suturing) and disintegrate on demand to microparticles facilitating the drug release.
In summary, the results of this thesis could confirm the central hypothesis that the variation of the geometry of polymeric micro-objects is a suitable parameter to adjust their shape-memory performance by changing the degree of macromolecular chain orientation in the specimens or by enabling new functions like on demand disintegration. These fundamental findings might be relevant for designing novel miniaturized multifunctional polymer-based devices.
Versammlungen sind der Ursprung der Demokratie. "Friedlich und ohne Waffen" darf der öffentliche Raum zur politischen Willensbildung genutzt werden. Aber gilt die Versammlungsfreiheit auch im öffentlichen Raum, der im privaten Eigentum steht? Diese Frage ist von großer Brisanz, wenn öffentlicher Raum privatisiert wird. Bahnhöfe, Flughäfen, Einkaufsstraßen und Marktplätze können im privaten Eigentum stehen - und dabei öffentlicher Raum bleiben. Müssen Eigentümer eines Geländes, das als öffentlicher Raum gestaltet ist, dort auch Versammlungen dulden? Wie verhält sich die Versammlungsfreiheit zum Schutz des Grundeigentums? Kann der Staat die Versammlungsfreiheit auf privatem Gelände durchsetzen? Und wie unterscheidet sich der Schutz zwischen der EMRK und dem Grundgesetz? Maria Scharlau geht der Frage nach, wie dieser Konflikt zwischen Versammlungsrecht und Eigentumsschutz zu lösen ist.
Samarium hexaboride
(2018)
Die Publikation zu Sprachwandelprozessen im Russischen und Ukrainischen beschreibt eine ausschlaggebende Phase der neueren Sprachgeschichte Russlands und der Ukraine (1985–2008). Im Fokus steht die Anglisierung als eine der Haupttendenzen der aktuellen sprachlichen Destandardisierung europäischer Sprachen. Die Autorin zeigt am Beispiel der Anglisierung in der Werbesprache die Destandardisierung des Russischen und Ukrainischen nach 1985 auf. Diese korpusbasierte Untersuchung umfasst sowohl die quantitative (statistische) als auch die qualitative (systemlinguistische) Analyse des werbesprachlichen Korpus. Die quantitative chronologische Analyse belegt die deutlich stärkere Dynamik der Anglisierung im Ukrainischen nach 1998. Die qualitative Analyse illustriert die unterschiedlichen bzw. gemeinsamen innerlinguistischen Prozesse in beiden Sprachen, insbesondere Anglizismen-Integration und Standardisierungswege.
Polymeric materials, which can perform reversible shape changes after programming, in response to a thermal or electrical stimulation, can serve as (soft) actuating components in devices like artificial muscles, photonics, robotics or sensors. Such polymeric actuators can be realized with hydrogels, liquid crystalline elastomers, electro-active polymers or shape-memory polymers by controlling with stumuli such as heat, light, electrostatic or magnetic field. If the application conditions do not allow the direct heating or electric stimulation of these smart devices, noncontact triggering will be required. Remotely controlled actuation have been reported for liquid crystalline elastomer composites or shape-memory polymer network composites, when a persistent external stress is applied during inductive heating in an alternating magnetic field. However such composites cannot meet the demands of applications requiring remotely controlled free-standing motions of the actuating components.
The current thesis investigates, whether a reprogrammable remotely controlled soft actuator can be realized by magneto-sensitive multiphase shape-memory copolymer network composites containing magnetite nanoparticles as magneto-sensitive multivalent netpoints. A central hypothesis was that a magnetically controlled two-way (reversible bidirectional) shape-memory effect in such nanocomposites can be achieved without application of external stress (freestanding), when the required orientation of the crystallizable actuation domains (ADs) can be ensured by an internal skeleton like structure formed by a second crystallizable phase determing the samples´s geometry, while magneto-sensitive iron oxide nanoparticles covalently integrated in the ADs allow remote temperature control. The polymer matrix of these composites should exhibit a phase-segregated morphology mainly composed of cyrstallizable ADs, whereby a second set of higher melting crystallites can take a skeleton like, geometry determining function (geometry determining domains, GDs) after programming of the composite and in this way the orientation of the ADs is established and maintained during actuation. The working principle for the reversible bidirectional movements in the multiphase shape-memory polymer network composite is related to a melting-induced contraction (MIC) during inductive heating and the crystallization induced elongation (CIE) of the oriented ADs during cooling. Finally, the amount of multivalent magnetosensitive netpoints in such a material should be as low as possible to ensure an adequate overall elasticity of the nanocomposite and at the same time a complete melting of both ADs and GDs via inductive heating, which is mandatory for enabling reprogrammability.
At first, surface decorated iron oxide nanoparticles were synthesized and investigated. The coprecipitation method was applied to synthesize magnetic nanoparticles (mNPs) based on magnetite with size of 12±3 nm and in a next step a ring-opening polymerization (ROP) was utilized for covalent surface modification of such mNPs with oligo(ϵ-caprolactone) (OCL) or oligo(ω-pentadecalactone) (OPDL) via the “grafting from” approach. A successful coating of mNPs with OCL and OPDL was confirmed by differential scanning calorimetry (DSC) experiments showing melting peaks at 52±1 °C for mNP-OCL and 89±1 °C for mNP-OPDL. It was further explored whether two-layered surface decorated mNPs, can be prepared via a second surface-initiated ROP of mNP-OCL or mNP-OPDL with ω-pentadecalactone or ϵ-caprolactone. The observation of two distinct melting transitions in DSC experiments as well as the increase in molecular weight of the detached coatings determined by GPC and 1H-NMR indicated a successful synthesis of the twolayered nanoparticles mNP-OCL-OPDL and mNP-OPDL-OCL. In contrast TEM micrographs revealed a reduction of the thickness of the polymeric coating on the nanoparticles after the second ROP, indicating that the applied synthesis and purification required further optimization.
For evaluating the impact of the dispersion of mNPs within a polymer matrix on the resulting inductive heating capability of composites, plain mNPs as well as OCL coated magnetite nanoparticles (mNP-OCLs) were physically incorporated into crosslinked poly(ε-caprolactone) (PCL) networks. Inductive heating experiments were performed with both networks cPCL/mNP and cPCL/mNP-OCL in an alternating magnetic field (AMF) with a magnetic field strength of H = 30 kA·m-1. Here a bulk temperature of Tbulk = 74±2 °C was achieved for cPCL/mNP-OCL, which was almost 20 °C higher than the melting transition of the PCL-based polymer matrix. In contrast, the composite with plain mNPs could only reach a Tbulk of 48±2 °C, which is not sufficient for a complete melting of all PCL crystallites as required for actuation.
The inductive heating capability of a multiphase copolymer nanocomposite network (designed as soft actuators) containing surface decorated mNPs as covalent netpoints was investigated. Such composite was synthesized from star-shaped OCL and OPDL precursors, as well as mNP-OCLs via reaction with HDI. The weight ratio of OPDL and OCL in the starting reaction mixture was 15/85 (wt%/wt%) and the amount of iron oxide in the nanocomposite was 4 wt%. DSC experiments revealed two well separated melting and crystallization peaks confirming the required phase-segregated morphology in the nanocomposite NC-mNP-OCL. TEM images could illustrate a phase-segregated morphology of the polymer matrix on the microlevel with droplet shaped regions attributed to the OPDL domains dispersed in an OCL matrix. The TEM images could further demonstrate that the nanoparticulate netpoints in NC-mNP-OCL were almost homogeneously dispersed within the OCL domains. The tests of the inductive heating capability of the nanocomposites at a magnetic field strength of Hhigh = 11.2 kA·m-1 revealed a achievable plateau surface temperature of Tsurf = 57±1 °C for NC-mNP-OCL recorded by an infrared video camera. An effective heat generation constant (̅P) can be derived from a multi-scale model for the heat generation, which is proportional to the rate of heat generation per unit volume of the sample. NC-mNP-OCL with homogeneously dispersed mNP-OCLs exhibited a ̅P value of 1.04±0.01 K·s- 1 at Hhigh, while at Hreset = 30.0 kA·m-1 a Tsurf of 88±1 °C (where all OPDL related crystallite are molten) and a ̅P value of 1.93±0.02 K·s-1 was obtained indicating a high magnetic heating capability of the composite.
The free-standing magnetically-controlled reversible shape-memory effect (mrSME) was explored with originally straight nanocomposite samples programmed by bending to an angle of 180°. By switching the magnetic field on and off the composite sample was allowed to repetitively heat to 60 °C and cool to the ambient temperature. A pronounced mrSME, characterized by changes in bending angle of Δϐrev = 20±3° could be obtained for a composite sample programmed by bending when a magnetic field strength of Hhigh = 11.2 kA·m-1 was applied in a multi-cyclic magnetic bending experiment with 600 heating-cooling cycles it could be shown that the actuation performance did not change with increasing number of test cycles, demonstrating the accuracy and reproducibility of this soft actuator. The degree of actuation as well as the kinetics of the shape changes during heating could be tuned by variation of the magnetic filed strength between Hlow and Hhigh or the magnetic field exposure time. When Hreset = 30.0 kA·m-1 was applied the programmed geometry was erased and the composite sample returned to it´s originally straight shape. The reprogrammability of the nanocomposite actuators was demonstrated by one and the same test specimen first exhibiting reversible angle changes when programmed by bending, secondly reprogrammed to a concertina, which expands upon inductive heating and contracts during cooling and finally reprogrammed to a clip like shape, which closes during cooling and opens when Hhigh was applied. In a next step the applicability of the presented remote controllable shape-memory polymer actuators was demonstrated by repetitive opening and closing of a multiring device prepared from NC-mNP-OCL, which repetitively opens and closes when a alternating magnetic field (Hhigh = 11.2 kA·m-1) was switched on and off.
For investigation of the micro- and nanostructural changes related to the actuation of the developed nanocomposite, AFM and WAXS experiments were conducted with programmed nanocomposite samples under cyclic heating and cooling between 25 °C and 60 °C. In AFM experiments the change in the distance (D) between representative droplet-like structures related to the OPDL geometry determining domains was used to calculate the reversible change in D. Here Drev = 3.5±1% was found for NC-mNP-OCL which was in good agreement with the results of the magneto-mechanical actuation experiments. Finally, the analysis of azimuthal (radial) WAXS scattering profiles could support the oriented crystallization of the OCL actuation domains at 25 °C.
In conclusion, the results of this work successfully demonstrated that shape-memory polymer nanocomposites, containing mNPs as magneto-sensitive multifunctional netpoints in a covalently crosslinked multiphase polymer matrix, exhibit magnetically (remotely) controlled actuations upon repetitive exposure to an alternating magnetic field. Furthermore, the (shape) memory of such a nanocomposite can be erased by exposing it to temperatures above the melting temperature of the geometry forming domains, which allows a reprogramming of the actuator. These findings would be relevant for designing novel reprogrammable remotely controllable soft polymeric actuators.
The highly conserved protein complex containing the Target of Rapamycin (TOR) kinase is known to integrate intra- and extra-cellular stimuli controlling nutrient allocation and cellular growth. This thesis describes three studies aimed to understand how TOR signaling pathway influences carbon and nitrogen metabolism in Chlamydomonas reinhardtii. The first study presents a time-resolved analysis of the molecular and physiological features across the diurnal cycle. The inhibition of TOR leads to 50% reduction in growth followed by nonlinear delays in the cell cycle progression. The metabolomics analysis showed that the growth repression is mainly driven by differential carbon partitioning between anabolic and catabolic processes. Furthermore, the high accumulation of nitrogen-containing compounds indicated that TOR kinase controls the carbon to nitrogen balance of the cell, which is responsible for biomass accumulation, growth and cell cycle progression. In the second study the cause of the high accumulation of amino acids is explained. For this purpose, the effect of TOR inhibition on Chlamydomonas was examined under different growth regimes using stable 13C- and 15N-isotope labeling. The data clearly showed that an increased nitrogen uptake is induced within minutes after the inhibition of TOR. Interestingly, this increased N-influx is accompanied by increased activities of nitrogen assimilating enzymes. Accordingly, it was concluded that TOR inhibition induces de-novo amino acid synthesis in Chlamydomonas. The recognition of this novel process opened an array of questions regarding potential links between central metabolism and TOR signaling. Therefore a detailed phosphoproteomics study was conducted to identify the potential substrates of TOR pathway regulating central metabolism. Interestingly, some of the key enzymes involved in carbon metabolism as well as amino acid synthesis exhibited significant changes in the phosphosite intensities immediately after TOR inhibition. Altogether, these studies provide a) detailed insights to metabolic response of Chlamydomonas to TOR inhibition, b) identification of a novel process causing rapid upshifts in amino acid levels upon TOR inhibition and c) finally highlight potential targets of TOR signaling regulating changes in central metabolism. Further biochemical and molecular investigations could confirm these observations and advance the understanding of growth signaling in microalgae.
Ab 1806 versuchte Napoleon über sieben Jahre hinweg, den europäischen Kontinent gegen jegliche Importe aus Großbritannien abzuschotten. Dieses protektionistische Großexperiment löste in der zeitgenössischen Presse intensive Debatten zu wirtschaftstheoretischen Fragen aus: Fördert ökonomischer Isolationismus den nationalen Wohlstand? Können internationale Rechtsregelungen einem Handelskrieg entgegenwirken? Oder werden nationaler Wohlstand und damit globaler Frieden nicht eher durch allgemeinen Freihandel begünstigt? Alix Winter stellt das wirtschaftspolitische Ereignis der Kontinentalsperre als Kristallisationspunkt öffentlicher Auseinandersetzungen über ökonomische Grundsatzfragen heraus und identifiziert das frühe 19. Jahrhundert als Radikalisierungsphase aufklärerischer liberaler Wirtschaftstheorien.In 1806, Napoleon attempted to seal off the entire European continent from British imports. This ambitious protectionist experiment set off extensive debates about questions of economic theory. Did economic isolation foster the wealth of nations? Could international law prevent the outbreak of a maritime trade war? Or would global free trade promote wealth and peace among all nations? In this book, Alix Winter studies how the continental system served as a focal point for public discussions about fundamental economical questions and how the early nineteenth century witnessed the radicalisation of Enlightenment liberal economic theories.
Ostdeutsche Ehen vor Gericht
(2018)
Die DDR hatte eine der weltweit höchsten Scheidungsraten. Die Ehescheidung war mit nur wenigen Hürden verbunden und wurde weitgehend als Privatsache betrachtet. Doch ab 1990 trafen ost- und westdeutsche Bürger und Juristen
mit unterschiedlichen Erfahrungen aufeinander. Anja Schröter betrachtet die Scheidungspraxis in Ostdeutschland vom letzten Jahrzehnt der DDR über die Epochenzäsur 1989/90 hinweg bis zur Jahrtausendwende. Sie hat Juristen und ostdeutsche Bürger nach ihren Erfahrungen gefragt. Eine faszinierende Studie zum ostdeutschen Alltag im Umbruch.
In this thesis, we discuss the characterization of orthogroups by so-called disjunctions of identities. The orthogroups are a subclass of the class of completely regular semigroups, a generalization of the concept of a group. Thus there is for all elements of an orthogroup some kind of an inverse element such that both elements commute. Based on a fundamental result by A.H. Clifford, every completely regular semigroup is a semilattice of completely simple semigroups. This allows the description the gross structure of such semigroup. In particular every orthogroup is a semilattice of rectangular groups which are isomorphic to direct products of rectangular bands and groups. Semilattices of rectangular groups coming from various classes are characterized using the concept of an alternative variety, a generalization of the classical idea of a variety by Birkhoff.
After starting with some fundamental definitions and results concerning semigroups, we introduce the concept of disjunctions of identities and summarize some necessary properties. In particular we present some disjunction of identities which is sufficient for a semigroup for being completely regular. Furthermore we derive from this identity some statements concerning Rees matrix semigroups, a possible representation of completely simple semigroups. A main result of this thesis is the general description of disjunctions of identities such that a completely regular semigroup satisfying the described identity is a semilattice of left groups (right groups / groups). In this case the completely regular semigroup is an orthogroup. Furthermore we define various classes of rectangular groups such that there is an exponent taken from a set of pairwise coprime positive integers. An important result is the characterization of the class of all semilattices of particular rectangular groups (taken from the classes defined before) using a set-theoretic minimal set of disjunctions of identities. Additionally we investigate semilattices of groups (so-called Clifford semigroups). For this purpose we consider abelian groups of particular exponents and prove some well-known results from the theory of Clifford semigroups in an alternative way applying the concept of disjunctions of identities. As a practical application of the results concerning semilattices of left zero semigroups and right zero semigroups we identify a particular transformation semigroup. For more detailed information about the product of two arbitrary elements of a semilattice of semigroups we introduce the concept of strong semilattices of semigroups. It is well-known that a semilattice of groups is a strong semilattice of groups. So we can characterize a strong semilattice of groups of particular pairwise coprime exponents by disjunctions of identities. Additionally we describe the class of all strong semilattices of left zero semigroups and right zero semigroups with the help of such kind of identity, and we relate this statement to the theory of normal bands. A possible extension of the already described semilattices of rectangular groups can be achieved by an auxiliary total order (in terms of chains of semigroups). To this end we present a corresponding characterization due to disjunctions of identities which is obviously minimal. A list of open questions which have arisen during the research for this thesis, but left crude, is attached.
On a small scale
(2018)
This study argues that micro relations matter in peacekeeping. Asking what makes the implementation of peacekeeping interventions complex and how complexity is resolved, I find that formal, contractual mechanisms only rarely effectively reduce complexity – and that micro relations fill this gap. Micro relations are personal relationships resulting from frequent face-to-face interaction in professional and – equally importantly – social contexts.
This study offers an explanation as to why micro relations are important for coping with complexity, in the form of a causal mechanism. For this purpose, I bring together theoretical and empirical knowledge: I draw upon the current debate on ‘institutional complexity’ (Greenwood et al. 2011) in organizational institutionalism as well as original empirical evidence from a within-case study of the peacekeeping intervention in Haiti, gained in ten weeks of field research. In this study, scholarship on institutional complexity serves to identify theoretical causal channels which guide empirical analysis. An additional, secondary aim is pursued with this mechanism-centered approach: testing the utility of Beach and Pedersen’s (2013) theory-testing process tracing.
Regarding the first research question – what makes the implementation of peacekeeping interventions complex –, the central finding is that complexity manifests itself in the dual role of organizations as cooperation partners and competitors for (scarce) resources, turf and influence. UN organizations, donor agencies and international NGOs implementing peacekeeping activities in post-conflict environments have chronic difficulty mastering both roles because they entail contradictory demands: effective cooperation requires information exchange, resource and responsibility-sharing as well as external scrutiny, whereas prevailing over competitors demands that organizations conceal information, guard resources, increase relative turf and influence, as well as shield themselves from scrutiny. Competition fuels organizational distrust and friction – and impedes cooperation.
How is this complexity resolved? The answer to this second research question is that deep-seated organizational competition is routinely mediated – and cooperation motivated – in micro relations and micro interaction. Regular, frequent face-to-face interaction between individual organizational members generates social resources that help to transcend organizational distrust and conflict, most importantly familiarity with each other, personal trust and belief in reciprocity. Furthermore, informal conflict mediation and control mechanisms – namely, open discussion, mutual monitoring in direct interaction and social exclusion – enhance solidarity and mutual support.
Der 20. Juli 1944 zählt zu den Schlüsselereignissen der deutschen Geschichte des 20. Jahrhunderts. Das missglückte Attentat von Claus Schenk Graf von Stauffenberg auf Adolf Hitler und der anschließende Umsturzversuch sind zum Symbol des Widerstandes gegen den Nationalsozialismus geworden. Von den Ereignissen völlig überrascht, hatte das NS-Regime in Bezug auf die Gruppe der Verschwörer sofort festgelegt, dass in der Öffentlichkeit nur von einer »ganz kleinen Clique« die Rede sein dürfe – eine Formulierung, die mitunter noch heute das Bild des Widerstandskreises prägt.
Die vorliegende Analyse zeigt erstmals anhand von zahlreichen Netzwerkvisualisierungen, was die NS-Ermittler tatsächlich über das große und komplexe zivile und militärische Netzwerk vom 20. Juli 1944 wussten, das so unterschiedliche gesellschaftliche Gruppen umfasste wie Offiziere, Verwaltungsbeamte, Diplomaten, Juristen, Industrielle, Theologen, Gutsbesitzer, Gewerkschafter und Sozialdemokraten. Zeitgenössische Briefe und Tagebücher verdeutlichen schließlich das geschickte Agieren der Verschwörer vor und nach dem Umsturzversuch und offenbaren zudem die Fehlerhaftigkeit der NS-Quellen.
Companies have a keen interest in developing skilled negotiators in order to improve their negotiation outcome. A crucial determinant of the negotiation outcome are negotiation styles that represent the negotiator’s actual behavior during the negotiation process. In this context, the author examines the variation in negotiation styles throughout the negotiation process, points out the relevance of the negotiator’s characteristics and situational context as determinants of negotiation styles, and emphasizes the importance not only of actual but also of perceived negotiation behavior. As a result, existing negotiation research is advanced as new perspectives on negotiation styles are offered to improve a negotiator’s performance.
Nanoparticles (NPs) are particles between 1 and 100 nanometers in size. They have attracted enormous research interests owing to their remarkable physicochemical properties and potential applications in the optics, catalysis, sensing, electronics, or optical devices. The thesis investigates systems of NPs attached to planar substrates.
In the first part of the results section of the thesis a new method is presented to immobilize NPs. In many NP applications a strong, persistent adhesion to substrates is a key requirement. Up to now this has been achieved with various methods, which are not always the optimum regarding adhesion strength or applicability. We propose a new method which uses capillarity to enhance the binding agents in the contact area between NP and substrate. The adhesion strength resulting from the new approach is investigated in detail and it is shown that the new approach is superior to older methods in several ways.
The following section presents the optical visualization of nano-sized objects through a combination of thin film surface distortion and interference enhanced optical reflection microscopy. It is a new, fast and non-destructive technique. It not only reveals the location of NPs as small as 20nm attached to planar surfaces and embedded in a molecularly thin liquid film. It also allows the measurement of the geometry of the surface distortion of the liquid film. Even for small NPs the meniscus reaches out for micrometers, which is the reason why the NPs produce such a pronounced optical footprint.
The nucleation and growth of individual bubbles is presented in chapter 5. Nucleation is a ubiquitous natural phenomenon and of great importance in numerous industrial processes. Typically it occurs on very small scales (nanometers) and it is of a random nature (thermodynamics of small systems). Up to now most experimental nucleation studies deal with a large number of individual nucleation processes to cope with its inherently statistical, spatio-temporal character. In contrast, in this thesis the individual O2-bubble formation from single localized platinum NP active site is studied experimentally. The bubble formation is initiated by the catalytic reaction of H2O2 on the Pt surface. It is studied how the bubble nucleation and growth depends on the NP size, the H2O2 concentration and the substrate surface properties. It is observed that in some cases the bubbles move laterally over the substrate surface, driven by the O2-production and the film ablation.