@phdthesis{GilPulido2018, author = {Gil Pulido, Jes{\´u}s}, title = {The role of Batf3-dependent dendritic cells and the IL-23 receptor in atherosclerosis}, doi = {10.25972/OPUS-16720}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167203}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {Cardiovascular diseases represent the leading cause of death worldwide, with myocardial infarction and strokes being the most common complications. In both cases, the appearance of an enlarged artery wall as a consequence of a growing plaque is responsible for the disturbance of the blood flow. The formation of plaques is driven by a chronic inflammatory condition known as atherosclerosis, characterized by an initial step of endothelial cell (EC) dysfunction followed by the recruitment of circulating immune cells into the tunica intima of the vessel. Accumulation of lipids and cells lead to the formation of atheromatous plaques that will define the cardiovascular outcome of an individual. The role of the immune system in the progression of atherosclerosis has been widely recognized. By far, macrophages constitute the most abundant cell type in lesions and are known to be the major source of the lipid-laden foam cell pool during the course of the disease. However, other immune cells types, including T cells, dendritic cells (DCs) or mast cells, among others, have been described to be present in human and mouse plaques. How these populations can modulate the atherogenic process is dependent on their specialized function. DCs constitute a unique population with the ability to bridge innate and adaptive immune responses, mainly by their strong capacity to present antigens bound to a major histocompatibility complex (MHC) molecule. Given their ability to polarize T cells and secrete cytokines, their role in atherosclerosis has gained attention for the development of new therapeutic approaches that could impact lesion growth. Hence, knowing the effect of a specific subset is an initial key step to evaluate its potential for clinical purposes. For example, the basic leucine zipper ATF-like 3 transcription factor (Batf3) controls the development of conventional dendritic cells type 1 (cDCs1), characterized by the expression of the surface markers CD8 and CD103. Initially, they were described to promote both T-helper 1 (Th1) and regulatory T cell (Treg) responses, known to accelerate and to protect against atherosclerosis, respectively. The first part of this thesis aimed to elucidate the potential role of Batf3-dependent DCs in atherosclerosis and concluded that even though systemic immune responses were mildly altered they do not modify the course of the disease and may not represent an attractive candidate for clinical studies. DCs also have the ability to impact lesion growth through the release of a broad range of cytokines, which can either directly impact atherosclerotic plaques by modulating resident cells, or by further polarizing T cell responses. Among others, interleukin (IL) 23, a member of the IL-12 family of cytokines, has received much attention during the past year due to its connection to autoimmunity. IL-23 is known to induce pathogenicity of Th17 cells and is responsible for the development of several autoimmune diseases including multiple sclerosis, psoriasis or rheumatoid arthritis. Interestingly, these patients often present with an accelerated course of atherosclerosis and thus, are at higher risk of developing cardiovascular events. Several epidemiological studies have pointed toward a possible connection between IL-23 and its receptor IL-23R in atherosclerosis, although their exact contribution remains to be elucidated. The second part of this thesis showed that resident antigen-presenting cells (APCs) in the aorta produced IL-23 during the steady state but this secretion was greatly enhanced after incubation with oxidized low-density lipoprotein (oxLDL). Furthermore, disruption of the IL-23R signaling led to decreased relative necrotic plaque area in lesions of Ldlr-/-Il23r-/- mice fed a high-fat diet (HFD) for 6 and 12 weeks compared to Ldlr-/- controls. A proposed mechanism involves that increased IL-23 production in the context of atherosclerosis may promote the pathogenicity of IL-23-responding T cells, especially IL-23R+ γδ T cells in the aortic root. Response to IL-23 might increase the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-17 and alter the pro- and anti-inflammatory balance of cytokines in the aortic root. Altogether, these data showed that the IL-23 / IL-23R axis play a role in plaque stability.}, subject = {Arteriosklerose}, language = {en} } @phdthesis{Steck2018, author = {Steck, Daniel}, title = {Lagrange Multiplier Methods for Constrained Optimization and Variational Problems in Banach Spaces}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-174444}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {This thesis is concerned with a class of general-purpose algorithms for constrained minimization problems, variational inequalities, and quasi-variational inequalities in Banach spaces. A substantial amount of background material from Banach space theory, convex analysis, variational analysis, and optimization theory is presented, including some results which are refinements of those existing in the literature. This basis is used to formulate an augmented Lagrangian algorithm with multiplier safeguarding for the solution of constrained optimization problems in Banach spaces. The method is analyzed in terms of local and global convergence, and many popular problem classes such as nonlinear programming, semidefinite programming, and function space optimization are shown to be included as special cases of the general setting. The algorithmic framework is then extended to variational and quasi-variational inequalities, which include, by extension, Nash and generalized Nash equilibrium problems. For these problem classes, the convergence is analyzed in detail. The thesis then presents a rich collection of application examples for all problem classes, including implementation details and numerical results.}, subject = {Optimierung}, language = {en} } @phdthesis{Ziegenhals2018, author = {Ziegenhals, Thomas}, title = {The role of the miR-26 family in neurogenesis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-156395}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {For the differentiation of a embryonic stem cells (ESCs) to neuronal cells (NCs) a complex and coordinated gene regulation program is needed. One important control element for neuronal differentiation is the repressor element 1 silencing transcription factor (REST) complex, which represses neuronal gene expression in non-neuronal cells. Crucial effector proteins of the REST complex are small phosphatases such as the CTDSPs (C-terminal domain small phosphatases) that regulate polymerase II activity by dephosphorylating the C-terminal domain of the polymerase, thereby repressing target genes. The stepwise inactivation of REST, including the CTDSPs, leads to the induction of a neuron-specific gene program, which ultimately induces the formation of neurons. The spatio-temporal control of REST and its effector components is therefore a crucial step for neurogenesis. In zebrafish it was shown that the REST-associated CTDSP2 is negatively regulated by the micro RNA (miR) -26b. Interestingly, the miR-26b is encoded in an intron of the primary transcript of CTDSP2. This gives the fundament of an intrinsic regulatory negative feedback loop, which is essential for the proceeding of neurogenesis. This feedback loop is active during neurogenesis, but inactive in non-neuronal cells. The reason for this is that the maturation of the precursor miR (pre-miR) to the mature miR-26 is arrested in non neuronal cells, but not in neurons. As only mature miRs are actively repressing genes, the regulation of miR-26 processing is an essential step in neurogenesis. In this study, the molecular basis of miR-26 processing regulation in the context of neurogenesis was addressed. The mature miR is processed from two larger precursors: First the primary transcript is cleaved by the enzyme DROSHA in the nucleus to form the pre-miR. The pre-miR is exported from the nucleus and processed further through the enzyme DICER to yield the mature miR. The mature miR can regulate gene expression in association with the RNA-induced silencing complex (RISC). Multiple different scenarios in which miR processing was regulated were proposed and experimentally tested. Microinjection studies using Xenopus leavis oocytes showed that slowdown or blockage of the nucleo-cytoplasmic transport are not the reason for delayed pre-miR-26 processing. Moreover, in vitro and in vivo miR-processing assays showed that maturation is most likely regulated through a in trans acting factor, which blocks processing in non neuronal cells. Through RNA affinity chromatographic assays using zebrafish and murine lysates I was able to isolate and identify proteins that interact specifically with pre-miR-26 and could by this influence its biogenesis. Potential candidates are FMRP/FXR1/2, ZNF346 and Eral1, whose functional characterisation in the context of miR-biogenesis could now be addressed. The second part of my thesis was executed in close colaboration with the laboratory of Prof. Albrecht M{\"u}ller. The principal question was addressed how miR-26 influences neuronal gene expression and which genes are primarily affected. This research question could be addressed by using a cell culture model system, which mimics ex vivo the differentiation of ESCs to NCs via neuronal progenitor. For the functional analysis of miR-26 knock out cell lines were generated by the CRISPR/Cas9 technology. miR-26 deficient ESC keep their pluripotent state and are able to develop NPC, but show major impairment in differentiating to NCs. Through RNA deep sequencing the miR-26 induced transcriptome differences could be analysed. On the level of mRNAs it could be shown, that the expression of neuronal gene is downregulated in miR-26 deficient NCs. Interestingly, the deletion of miR-26 leads to selectively decreased levels of miRs, which on one hand regulate the REST complex and on the other hand are under transcriptional control by REST themself. This data and the discovery that induction of miR-26 leads to enrichment of other REST regulating miRs indicates that miR-26 initiates neurogenesis through stepwise inactivation of the REST complex.}, subject = {miRNS}, language = {en} } @phdthesis{Schoetz2018, author = {Sch{\"o}tz, Matthias}, title = {Convergent Star Products and Abstract O*-Algebras}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-174355}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {Diese Dissertation behandelt ein Problem aus der Deformationsquantisierung: Nachdem man die Quantisierung eines klassischen Systems konstruiert hat, w{\"u}rde man gerne ihre mathematischen Eigenschaften verstehen (sowohl die des klassischen Systems als auch die des Quantensystems). Falls beide Systeme durch *-Algebren {\"u}ber dem K{\"o}rper der komplexen Zahlen beschrieben werden, bedeutet dies dass man die Eigenschaften bestimmter *-Algebren verstehen muss: Welche Darstellungen gibt es? Was sind deren Eigenschaften? Wie k{\"o}nnen die Zust{\"a}nde in diesen Darstellungen beschrieben werden? Wie kann das Spektrum der Observablen beschrieben werden? Um eine hinreichend allgemeine Behandlung dieser Fragen zu erm{\"o}glichen, wird das Konzept von abstrakten O*-Algebren entwickelt. Dies sind im Wesentlichen *-Algebren zusammen mit einem Kegel positiver linearer Funktionale darauf (z.B. die stetigen positiven linearen Funktionale wenn man mit einer *-Algebra startet, die mit einer gutartigen Topologie versehen ist). Im Anschluss daran wird dieser Ansatz dann auf zwei Beispiele aus der Deformationsquantisierung angewandt, die im Detail untersucht werden.}, subject = {Deformationsquantisierung}, language = {en} } @phdthesis{Schreck2018, author = {Schreck, Maximilian}, title = {Synthesis and Photophysics of Linear and Star-Shaped Oligomers of Squaraine Dyes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-174272}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {In this thesis, the synthesis and photophysics of a great variety of squaraine dyes are presented. This variety is based on four parent squaraines containing either indolenine or quinoline heterocycles. By a suitable choice of the donor and acceptor unit, the optical properties can already be adapted to the properties desired on the stage of the monomer. To promote a further derivatisation of these dyes, diverse functional groups are attached to the monomers using transition metal-catalysed C-C coupling reactions. However, this has to be preceded by the synthesis of bromine-functionalised derivatives as a direct halogenation of squaraine dyes is not feasible. Therefore, the halogen function is already introduced in precursor molecules giving rise to a molecular building block system containing bromine-, boronic ester-, and alkyne-functionalised monomer units, which pave the way to a plethora of squaraine oligomers and polymers. The indolenine homopolymer pSQB-1 as well as the corresponding small molecular weight oligomers dSQB-1 and tSQB were synthesized applying Ni-mediated Yamamoto and Pd-catalysed Suzuki coupling methodologies, respectively. The motivation for this project relied on the fundamental investigations by V{\"o}lker et al. on pSQB-V. A progressive red-shift of the lowest energy absorption maximum from the dimer to the polymer was observed in CHCl3 compared to the monomer. With increasing number of monomer units, the exciton coupling decreases from the dimer to the polymer. In addition, the shape of the absorption band manifold shows a strong dependence on the solvent, which was also observed by V{\"o}lker et al. J-type aggregate behavior is found in chlorinated solvents such as CHCl3 and DCM, whereas H-type aggregates are formed in acetone. Temperature-dependent absorption studies in PhCN reveals a reversible equilibrium of diverse polymer conformers, which manifests itself in a gradual change from H-aggregate behavior to a mixture with a more pronounced J-aggregate behavior upon raising the temperature. It isassumed that both characteristic aggregate bands correlate in borderline cases with two polymer structures which can be assigned to a zig-zag and a helical structure. As no experimental evidence for these structures could hitherto be provided by NMR, TD-DFT computations on oligomers (22-mers) can reproduce very closely the characteristic features of the spectra for the two conformational isomers. The subsequent chapters are motivated by the goal to influence the optical properties through a control of the superstructure and thus of the intramolecular aggregate formation. On the one hand, bulky groups are implemented in the 3-position of the indolenine scaffold to provoke steric repulsion and thus favoring J-aggregate behavior at the expense of helical arrangements. The resulting homopolymer pDiPhSQB bearing two phenyl groups per indolenine exhibits J-type aggregate behavior with red-shifted absorption maxima in all considered solvents which is explained to be caused by the formation of elongated zig-zag structures. Furthermore, single-crystal X-ray analysis of monomer DiPhSQB-2-Br2 reveals a torsion of the indolenine moieties as a consequence of steric congestion. The twist of the molecular geometry and the resulting loss of planarity leads to a serious deterioration of the fluorescence properties, however a significant bathochromic shift of ca. 1 200 cm-1 of the lowest absorption band was observed compared to parent SQB, which is even larger than the shift for dSQB-1 (ca. 1 000 cm-1). On the other hand, a partial stiffening of the polymer backbone is attempted to create a bias for elongated polymer chains. In this respect, the synthetic approach is to replace every second biarylaxis with the rigid transoid benzodipyrrolenine unit. Despite a rather low average degree of polymerization < 10, exclusively red-shifted absorption maxima are observed in all solvents used. In order to complete the picture of intramolecular aggregates through the selective design of H-aggregates, a squaraine-squaraine copolymer was synthesised containing the classic cisoid indolenine as well as the cisoid quinoline building block. Taking advantage of the highly structure directing self-assembly character of the quinoline moiety, the copolymer pSQBC indeed showes a broad, blue-shifted main absorption band in comparison with the monomer unit dSQBC. The shape of the absorption band manifold solely exhibited a minor solvent and temperature dependence indicating a persistent H-aggregate behaviour. Hence, as a proof of concept, it is shown that the optical properties of the polymers (H- and J-aggregate) and the corresponding superstructure can be inherently controlled by an adequate design of monomer precursors. The last chapter of this work deals, in contrast to all other chapters, with intermolecular aggregates. It is shown that the two star-shaped hexasquarainyl benzenes hSQA-1 and hSQA-2 exhibit a strong propensity for self-organisation. Concentration- and temperature-dependent studies reveal a great driving force for self-assembly in acetone. While the larger hSQA-2 instantaneously forms stable aggregates, the aggregates of hSQA-1 shows a pronounced kinetic stability. Taking advantage of the kinetic persistency of these aggregates, the corresponding kinetic activation parameters for aggregation and deaggregation can be assessed. The absorption spectra of both hexasquarainyl benzenes in the aggregated state reveal some striking differences. While hSQA-1 features an intensive, very narrow and blue-shifted absorption band, two red-shifted bands are observed for hSQA-2, which are closely located at the monomer absorption. The very small bandwidth of hSQA-1 are interpreted to be caused by exchange narrowing and pointed towards highly ordered supramolecular aggregates. The concentration-dependent data of the two hexasquarainyl benzenes can be fitted to the dimer-model with excellent correlation coefficients, yielding binding constants in excess of 10^6 M-1, respectively. Such high binding constants are very surprising, considering the unfavourable bulky 3,3-dimethyl groups of the indolenine units which should rather prevent aggregation. Joint theoretical and NMR spectroscopic methods were applied to unravel the supramolecular aggregate structure of hSQA-1, which is shown to consist of two stacked hexasquarainyl benzenes resembling the picture of two stacked bowls.}, subject = {Squaraine}, language = {en} } @phdthesis{Lerch2018, author = {Lerch, Maike Franziska}, title = {Characterisation of a novel non-coding RNA and its involvement in polysaccharide intercellular adhesin (PIA)-mediated biofilm formation of \(Staphylococcus\) \(epidermidis\)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-155777}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, have been recognised as an important cause of health care-associated infections due to catheterisation, and livestock-associated infections. The colonisation of indwelling medical devices is achieved by the formation of biofilms, which are large cell-clusters surrounded by an extracellular matrix. This extracellular matrix consists mainly of PIA (polysaccharide intercellular adhesin), which is encoded by the icaADBC-operon. The importance of icaADBC in clinical strains provoking severe infections initiated numerous investigations of this operon and its regulation within the last two decades. The discovery of a long transcript being located next to icaADBC, downstream of the regulator gene icaR, led to the hypothesis of a possible involvement of this transcript in the regulation of biofilm formation (Eckart, 2006). Goal of this work was to characterise this transcript, named ncRNA IcaZ, in molecular detail and to uncover its functional role in S. epidermidis. The ~400 nt long IcaZ is specific for ica-positive S. epidermidis and is transcribed in early- and mid-exponential growth phase as primary transcript. The promotor sequence and the first nucleotides of icaZ overlap with the 3' UTR of the preceding icaR gene, whereas the terminator sequence is shared by tRNAThr-4, being located convergently to icaZ. Deletion of icaZ resulted in a macroscopic biofilm-negative phenotype with highly diminished PIA-biofilm. Biofilm composition was analysed in vitro by classical crystal violet assays and in vivo by confocal laser scanning microscopy under flow conditions to display biofilm formation in real-time. The mutant showed clear defects in initial adherence and decreased cell-cell adherence, and was therefore not able to form a proper biofilm under flow in contrast to the wildtype. Restoration of PIA upon providing icaZ complementation from plasmids revealed inconsistent results in the various mutant backgrounds. To uncover the functional role of IcaZ, transcriptomic and proteomic analysis was carried out, providing some hints on candidate targets, but the varying biofilm phenotypes of wildtype and icaZ mutants made it difficult to identify direct IcaZ mRNA targets. Pulse expression of icaZ was then used as direct fishing method and computational target predictions were executed with candidate mRNAs from aforesaid approaches. The combined data of these analyses suggested an involvement of icaR in IcaZ-mediated biofilm control. Therefore, RNA binding assays were established for IcaZ and icaR mRNA. A positive gel shift was maintained with icaR 3' UTR and with 5'/3' icaR mRNA fusion product, whereas no gel shift was obtained with icaA mRNA. From these assays, it was assumed that IcaZ regulates icaR mRNA expression in S. epidermidis. S. aureus instead lacks ncRNA IcaZ and its icaR mRNA was shown to undergo autoregulation under so far unknown circumstances by intra- or intermolecular binding of 5' UTR and 3' UTR (Ruiz de los Mozos et al., 2013). Here, the Shine-Dalgarno sequence is blocked through 5'/3' UTR base pairing and RNase III, an endoribonuclease, degrades icaR mRNA, leading to translational blockade. In this work, icaR mRNA autoregulation was therefore analysed experimentally in S. epidermidis and results showed that this specific autoregulation does not take place in this organism. An involvement of RNase III in the degradation process could not be verified here. GFP-reporter plasmids were generated to visualise the interaction, but have to be improved for further investigations. In conclusion, IcaZ was found to interact with icaR mRNA, thereby conceivably interfering with translation initiation of repressor IcaR, and thus to promote PIA synthesis and biofilm formation. In addition, the environmental factor ethanol was found to induce icaZ expression, while only weak or no effects were obtained with NaCl and glucose. Ethanol, actually is an ingredient of disinfectants in hospital settings and known as efficient effector for biofilm induction. As biofilm formation on medical devices is a critical factor hampering treatment of S. epidermidis infections in clinical care, the results of this thesis do not only contribute to better understanding of the complex network of biofilm regulation in staphylococci, but may also have practical relevance in the future.}, subject = {Biofilm}, language = {en} } @phdthesis{Budig2018, author = {Budig, Benedikt}, title = {Extracting Spatial Information from Historical Maps: Algorithms and Interaction}, edition = {1. Auflage}, publisher = {W{\"u}rzburg University Press}, address = {W{\"u}rzburg}, isbn = {978-3-95826-092-4}, doi = {10.25972/WUP-978-3-95826-093-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-160955}, school = {W{\"u}rzburg University Press}, pages = {viii, 160}, year = {2018}, abstract = {Historical maps are fascinating documents and a valuable source of information for scientists of various disciplines. Many of these maps are available as scanned bitmap images, but in order to make them searchable in useful ways, a structured representation of the contained information is desirable. This book deals with the extraction of spatial information from historical maps. This cannot be expected to be solved fully automatically (since it involves difficult semantics), but is also too tedious to be done manually at scale. The methodology used in this book combines the strengths of both computers and humans: it describes efficient algorithms to largely automate information extraction tasks and pairs these algorithms with smart user interactions to handle what is not understood by the algorithm. The effectiveness of this approach is shown for various kinds of spatial documents from the 16th to the early 20th century.}, subject = {Karte}, language = {en} } @phdthesis{Furth2018, author = {Furth, Sebastian}, title = {Linkable Technical Documentation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-174185}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {The success of semantic systems has been proven over the last years. Nowadays, Linked Data is the driver for the rapid development of ever new intelligent systems. Especially in enterprise environments semantic systems successfully support more and more business processes. This is especially true for after sales service in the mechanical engineering domain. Here, service technicians need effective access to relevant technical documentation in order to diagnose and solve problems and defects. Therefore, the usage of semantic information retrieval systems has become the new system metaphor. Unlike classical retrieval software Linked Enterprise Data graphs are exploited to grant targeted and problem-oriented access to relevant documents. However, huge parts of legacy technical documents have not yet been integrated into Linked Enterprise Data graphs. Additionally, a plethora of information models for the semantic representation of technical information exists. The semantic maturity of these information models can hardly be measured. This thesis motivates that there is an inherent need for a self-contained semantification approach for technical documents. This work introduces a maturity model that allows to quickly assess existing documentation. Additionally, the approach comprises an abstracting semantic representation for technical documents that is aligned to all major standard information models. The semantic representation combines structural and rhetorical aspects to provide access to so called Core Documentation Entities. A novel and holistic semantification process describes how technical documents in different legacy formats can be transformed to a semantic and linked representation. The practical significance of the semantification approach depends on tools supporting its application. This work presents an accompanying tool chain of semantification applications, especially the semantification framework CAPLAN that is a highly integrated development and runtime environment for semantification processes. The complete semantification approach is evaluated in four real-life projects: in a spare part augmentation project, semantification projects for earth moving technology and harvesting technology, as well as an ontology population project for special purpose vehicles. Three additional case studies underline the broad applicability of the presented ideas.}, subject = {Linked Data}, language = {en} } @phdthesis{Seifert2018, author = {Seifert, Sabine}, title = {New Electron-Deficient Polycyclic Aromatic Dicarboximides by Palladium-Catalyzed C-C Coupling and Core Halogenation-Cyanation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-156200}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {The thesis describes the development of new synthetic strategies towards planar nanometer-sized and electron-deficient polycyclic aromatic dicarboximides, which are rather unexplored compared with the large variety of electron-rich polycyclic aromatic hydrocarbons and nanographenes. Thus, new polycyclic aromatic systems containing a different number of dicarboximide groups were designed since this class of compounds has revealed its significance in the past due to a range of desirable molecular properties and its high thermal and photochemical stability. The synthetic concept towards these systems includes different C-C coupling techniques that were combined within coupling cascade reactions. Therefore, this thesis provides new insights into the reactivity of aromatic substrates and elucidates mechanistic aspects of C-C coupling cascade reactions to facilitate the precise design of new and desirable materials based on polycyclic aromatic dicarboximides. Furthermore, structure-property relationships as well as the optical and electrochemical properties were investigated by UV/Vis absorption and fluorescence spectroscopy and cyclic or square wave voltammetry. Insights into the molecular structures in the solid state were obtained by single-crystal X-ray analysis. In subsequent studies, highly electron-deficient perylene bisimides and their reduced species have been investigated in detail. Thus, core-functionalized perylene bisimides were synthesized and UV/Vis absorption spectroscopy, spectroelectrochemistry and cyclic or square wave voltammetry were used to determine their optical properties and the stability of the individual reduced species.}, subject = {Kupplungsreaktion}, language = {en} } @phdthesis{Wandtner2018, author = {Wandtner, Bernhard}, title = {Non-driving related tasks in highly automated driving - Effects of task characteristics and drivers' self-regulation on take-over performance}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173956}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {The rise of automated driving will fundamentally change our mobility in the near future. This thesis specifically considers the stage of so called highly automated driving (Level 3, SAE International, 2014). At this level, a system carries out vehicle guidance in specific application areas, e.g. on highway roads. The driver can temporarily suspend from monitoring the driving task and might use the time by engaging in so called non-driving related tasks (NDR-tasks). However, the driver is still in charge to resume vehicle control when prompted by the system. This new role of the driver has to be critically examined from a human factors perspective. The main aim of this thesis was to systematically investigate the impact of different NDR-tasks on driver behavior and take-over performance. Wickens' (2008) architecture of multiple resource theory was chosen as theoretical framework, with the building blocks of multiplicity (task interference due to resource overlap), mental workload (task demands), and aspects of executive control or self-regulation. Specific adaptations and extensions of the theory were discussed to account for the context of NDR-task interactions in highly automated driving. Overall four driving simulator studies were carried out to investigate the role of these theoretical components. Study 1 showed that drivers focused NDR-task engagement on sections of highly automated compared to manual driving. In addition, drivers avoided task engagement prior to predictable take-over situations. These results indicate that self-regulatory behavior, as reported for manual driving, also takes place in the context of highly automated driving. Study 2 specifically addressed the impact of NDR-tasks' stimulus and response modalities on take-over performance. Results showed that particularly visual-manual tasks with high motoric load (including the need to get rid of a handheld object) had detrimental effects. However, drivers seemed to be aware of task specific distraction in take-over situations and strictly canceled visual-manual tasks compared to a low impairing auditory-vocal task. Study 3 revealed that also the mental demand of NDR-tasks should be considered for drivers' take-over performance. Finally, different human-machine-interfaces were developed and evaluated in Simulator Study 4. Concepts including an explicit pre-alert ("notification") clearly supported drivers' self-regulation and achieved high usability and acceptance ratings. Overall, this thesis indicates that the architecture of multiple resource theory provides a useful framework for research in this field. Practical implications arise regarding the potential legal regulation of NDR-tasks as well as the design of elaborated human-machine-interfaces.}, subject = {Autonomes Fahrzeug}, language = {en} }