Bøger udgivet af Sudwestdeutscher Verlag Fur Hochschulschriften AG

The observation of neutrino masses and lepton mixing has highlighted the incompleteness of the Standard Model of particle physics. In order to address these and further issues, Grand Unified Theories and flavor symmetries are considered. GUTs such as SU(5) are vertical symmetries unifying the SM particles into multiplets. They usually predict new particles which can naturally explain the smallness of the neutrino masses via the seesaw mechanism. Flavor symmetries are horizontal symmetries acting on the generation space of the SM particles. They can serve as an explanation for the different mixings in the quark and lepton sectors and their mass hierarchies. In this book, we develop and perform a new systematic model building approach comprising flavor symmetries, GUTs and the seesaw mechanism. The results of this approach are, e.g., diverse lepton flavor and GUT models, a systematic scan of lepton flavor violation, new mass matrices, a new understanding of lepton mixing angles, a general extension of the idea of quark-lepton complementarity theta_12=pi/4-epsilon/sqrt{2} and for the first time the QLC relation in an SU(5) GUT.

Cultivation of adherently growing cells inside three dimensional scaffolds gains more importance as speci¿c demands from medicine and industry arise. A huge challenge herein lies in nutrient supply all over the scaffold's volume. This work presents a perfusion bioreactor device for cell cultivation inside porous aluminium oxide ceramics. Different modes of inoculation have been assessed as well as a set of perfusion velocities. Uniform cell distribution has been assured by cell staining of scaffold's cross sections. Two elaborate approaches for determination of overall cellular proliferation are introduced, which overcome the challenge of cell release out of porous substrates. The bioreactor supports vital growth of CHO-K1, A549, MDCK and human primary fibroblasts on and in ceramic cylinders of 5 mm height and 10 mm diameter with perfusion velocities from 0.33-0.66 ml/(min*cm²). For week-long perfusion cultivation of CHO-K1 and human primary fibroblasts fibrous structures have been observed inside ceramic scaffolds, thus supporting the hypothesis of three dimensional cell cultivation with secretion of extra-cellular-matrix proteins.

As a non-intrusive flow measurement technique, particle image velocimetry (PIV) is of intense research interest to those investigating turbomachinery. In most of turbomachinery applications, the complexity of the flow structures requires the use of three-component or stereoscopic PIV and the geometrical scales of the machines require the use of endoscopes in order to access the flow channel. This work presents the development of the endoscopic stereoscopic PIV for flow investigation at the inlet of a process centrifugal compressor. A new image reconstruction method is presented, which is capable of resolving high order distortions of the endoscopic imaging. In order to improve the measurement accuracy, a method for the calibration of pressure and temperature signals under quasi-steady conditions is developed and its application to the flow measurements with the 5-hole pressure probes is presented. Finally, several aspects of the application of the PIV at the inlet of the compressor together with a typical result are presented for the first time.

This book introduces a novel approach to modeling the behavior of programs at runtime. The technique leverages the structure of object-oriented programs to derive models that describe the behavior of individual objects. Our approach mines object behavior models, finite state automata where states correspond to different states of an object, and transitions are caused by method invocations. Such models capture the effects of method invocations on an object's state. This approach is the first to combine the control-flow with information about the values of variables. It is implemented in the publicly available Adabu tool, which mines object behavior models from the executions of large interactive programs. This book also shows the usefulness of object behavior models for automatic fix generation and specification mining.

In this thesis the optical properties of quasi two-dimensional organic molecular crystals are investigated. Within this class of materials some systems are metallic, some are insulating due to charge-order, and others even become superconducting. The driving force behind the ground states is the di¿erent degree of e¿ective electronic correlations. Recent experimental and theoretical studies of strongly correlated materials suggest that ¿uctuations of the ordered state may mediate superconductivity. The intention of this work is to prove the presence of such charge ¿uctuations and reveal their relation to superconductivity. To do this, we investigated BEDT-TTF based organic conductors by optical spectroscopy covering a broad frequency (8-20000 cm-1 ) and temperature (1.8-300 K) range using FTIR- and THz-spectrometers. In addition, the transport properties are investigated by dc four-point contact measurements and microwave cavity perturbation technique.

The applications of steel in industry are very diverse and widespread. The basic principle involved in heat treatment is the process of heating and cooling. The industrial process of case hardening aims to harden just the workpiece case, letting the inner part softer. The macrosopical model presented here takes into account the diffusion of carbon in the workpiece at austenitic phase, the slow diffusion at high temperature and the rapid cooling, which produces the formation of the martensitic microstructure. During this process, phase transformations in steel take place, influenced by the non homogeneous carbon distribution. The mathematical model presented here consists of a nonlinear evolution equation for the temperature, coupled with a nonlinear evolution equation for the carbon concentration, both coupled with two ordinary differential equations describing the evolution of phase fractions. Existence and uniqueness of solutions are investigated and some numerical simulations are presented.

Over the last decade, the software product line domain has emerged as one of the most promising software development paradigms. The main benefits of a software product line approach are improvements in productivity, time to market, product quality, and customer satisfaction. Therefore, one topic that needs greater emphasis is testing of software product lines to achieve the required software quality assurance. Our concern is how to test a software product line as early as possible in order to detect errors, because the cost of error detected in early phases is much less compared to the cost of errors when detected later. The method suggested is a model-based, reuse-oriented test technique called Colored Model Based Testing for Software Product Lines (CMBT-SWPL). CMBT-SWPL is a requirements-based approach for efficiently generating tests for products in a software product line. This testing approach is used for validation and verification of product lines. It is a novel approach to test product lines using a Colored State Chart (CSC), which considers variability early in the product line development process.

The framework of the Quantum Inverse Scattering Method is used to study the hamiltonian of the XXX and XXZ spin chain with general boundary fields. Key ingredient is the underlying algebraic structure which is a combination of the Yang-Baxter algebra and a so-called Reflection algebra including boundary fields of arbitrary direction and strength. For spin chains with diagonal boundary fields this setup has been well studied using algebraic Bethe ansatz and the inverse problem was solved by Kitanine for infinite chain lengths. These results are picked up and generalized to arbitrary lengths using non-linear integral equations. In the case of non-diagonal boundary fields the lack of a reference state or pseudo vacuum prohibits the solution by algebraic Bethe ansatz. The method of separation of variables is not constrained in that sense and is applied to the XXX chain and a spin-boson model. Finally a different approach to the case of non-diagonal boundary conditions is studied. Starting from the so-called fusion hierarchy non-linear integral equations are derived bearing the possibility to extract information about an eigenvalue of a specific state.

This thesis considers the dark matter (DM) density distribution of the Milky Way. The DM is assumed to consist of weakly interacting massive particles. Their density distribution is constrained by astronomical observations. An important constraint is the so-called rotation curve (RC) of the Milky Way, which describes the rotation speed of matter around the Galactic centre as function of Galactocentric distance. It is shown that a ringlike DM component in the Galactic disc is necessary to describe the peculiar dips in the RC at 3 and 9 kpc from the centre in agreement with the dip in the gas flaring of the Milky Way. This substructure effects the local DM density which is of crucial importance for direct DM search experiments. The slight GeV excess in the spectra of diffuse Galactic gamma rays of the EGRET and Fermi satellite data are consistent with this DM density distribution, if this excess is attributed to DM annihilation.

In general, infection of a host by multiple pathogens has important clinical implications. In conjunction with HIV, co-infections are associated with a significantly decreased survival probability. Unexpectedly, long-term viremia of the apathogenic GB Virus C (GBV-C) leads to improved survival of GBV-C co-infected HIV patients. However, epidemiological studies cannot prove a causal relationship nor they distinguish whether the observed reduction in HIV associated morbidity and mortality is caused by GBV-C/HIV interference or if GBV-C serves just as a surrogate marker for a robust immune system. Therefore, cell culture experiments were necessary. Indeed, GBV-C inhibits different HIV strains and clades. The underlaying mechanism of HIV suppression is complex. In addition to GBV-C proteins, such as the E2 glycoprotein that possess the ability to inhibit HIV entry or the NS5A protein that may imair later HIV replication steps, GBV-C elicits antibodies that neutralize HIV comparable to the broad reactive human anti-gp41 antibodies 2F5 and 4E10, as well. Taken together a combination of both inhibitory effects present an innovative approach for further drug development and vaccine design.

Information Markets are online based market systems and utilize market mechanisms for the aggregation of information. Market prices can be interpreted to forecast outcomes of future events. Information Markets show impressive prediction accuracy and often outperform other forecasting methods and experts. However, Information Markets still have not become an established part of companies' forecasting strategies. Nevertheless, a promising application in companies is the usage of Information Markets for the assessment of innovations since it efficiently integrates many relevant people into decision making. In this work, experimental evidence for the assessment of innovations in companies is given. Results from a field experiment show that employees accept Enterprise Information Markets as a valuable method for innovation management. In an investigation about trading behavior and activity, it can be shown that permanent liquidity is essential in order to get continuous forecasts. Summarized, this work provides results from two field experiments and shows that Information Markets produce accurate results given an appropriate market design - even in small-size markets.

This book analysis the impact of private road transport under emission trading using two different Computable General Equilibrium models. A static multi-region model with special emphasis on the European Union, addresses the welfare impact of road transport under the European Emission Trading System. Including terms-of-trade effects, this model does not account for congestion which is the main externality of road transport. Furthermore, technological details of electricity generation which are an important factor in evaluating climate policies are not included. Therefore, the second model is a static Small Open Economy model of the German economy including congestion effects and detailed technological characteristics of electricity generation. The results of both models highlight the important role of already existing taxes on transport fuels for the evaluation of carbon mitigation measures in road transportation.

The Boolean conjunctive normal form (CNF) satisability problem, called SAT for short, gets as input a CNF formula and has to decide whether this formula admits a satisfying truth assignment. As is well known, the remarkable result by S. Cook in 1971 established SAT as the first and genuine complete problem for the complexity class NP. In this thesis we consider SAT for a subclass of CNF, the so called Mixed Horn formula class (MHF). A formula F 2 MHF consists of a 2-CNF part P and a Horn part H. We propose that MHF has a central relevance in CNF because many prominent NP-complete problems, e.g. Feedback Vertex Set, Vertex Cover, Dominating Set and Hitting Set, can easily be encoded as MHF. Furthermore, we show that SAT remains NP-complete for some interesting subclasses of MHF. We also provide algorithms for some of these subclasses solving SAT in a better running time than O(2^0.5284n) which is the best bound for MHF so far. In addition, we investigate the computational complexity of some prominent variants of SAT, namely not-all-equal SAT (NAE-SAT) and exact SAT (XSAT) restricted to the class of linear CNF formulas.

Like in several sectors of consumer demand, attitudes, believes, and the political environment may also influence the worldwide demand for tourism. Consequentially, this book concentrates on a wider range of determinants including non-economical (geographical and socio-cultural) factors of tourism demand and supply at a worldwide scale. The second intent is to analyze whether and how (sustainable) tourism can be a trigger for economic development. The results show that tourism is able to enhance economic growth in countries which are specialized in this industry. As an increasing willingness to pay for outbound tourism goes hand in hand with an increasing per capita income in the world, it is evidenced that tourism is a superior good. However, cultural openness of a society is an important precondition from the country of origins' point of view. Regarding the tourism exporting countries (countries of destination), the most interesting outcome is that biodiversity as a proxy for "nice nature" is an important supply factor of the economy. Together with the tourism's potential to enhance economic growth, this reflects the value biodiversity can play for economic development.

Phage-derived FC31 integrase represents an attractive tool for site-directed recombination in mammalian cells. Integration is based on recombination between attachment site attB and wt/pseudo-attP` site. Disadvantages are inefficient nonviral gene delivery and aberrant events (15% chromosomal rearrangements/deletions) within the host genome. The study's aim was to increase safety and efficiency of FC31 integrase. DNA binding domain was mutated by alanine scan, 22 mutants were evaluated for improved integration and intramolecular recombination. The combination of beneficial mutations in addition to optimization of the integrase plasmid dose enhanced integration efficiencies from 1.7 to 5.5-fold. Several mutants showed cell line-dependent integration activities. Excision assays between native attB/attP sites revealed 5 mutants with 2-fold enhanced activity. Enhanced recombination between attB and 3 described attP' sites (hot spots) in the mammalian genome assumed preferred specificity. 2 mutants showed similar integration activity as wt due to hFIX expression in mouse hepatocytes. Mutational analysis revealed an efficient approach for improvements of integration efficiency in vitro.

In self-organizing processes, the coaction of multitudes of system elements, which are by themselves autonomous, leads to the formation of global structures that are continuously and independently adapted to a changeable environment. The use of these phenomena in the development of distributed software systems is particularly attractive as it allows distributing flexible problem solving abilities for complex global problems among the basic system elements. Hence, these processes can be used as powerful means for the decentralized coordination of distributed systems. This dissertation proposes a construction framework for self-organizing distributed systems - whereas self-organization is understood as the participation of system elements in decentralized, adaptive processes, as a supplement to the functional software system. This approach allows equipping applications with self-organizing features. A systematic development approach is enabled by the elevation of the adaptive, decentralized inter-agent process, which governs the self-organized structure formation, to an independent design element.

The book addresses capillary phenomena, which at the macro-scale are a part of our everyday experience. This includes clustering of cereals in a bowl of milk or locomotion of insects on a water surface. At the micro-scale, when gravity can be neglected, capillary forces are even more pronounced as they determine the shape of free liquid interfaces and therefore become a major factor governing the behavior of microscopic objects trapped at these interfaces. The book describes the effective interactions between colloidal particles deforming the surface of a micron-sized droplet deposited on a solid substrate and the possible equilibrium configurations of the particles on the droplet. The issue is of big relevance for experimental techniques, frequently employed in science and industry, which use sessile droplets for transferring the self-assembled colloidal structures onto the substrates.