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Mit dieser Arbeit soll ein Vorschlag unterbreitet werden, wie gerichtliche Entscheidungen analysiert und bewertet werden können. Im Mittelpunkt der Arbeit steht dabei die von Karl Larenz aufgeworfene Fragestellung, unter welchen Voraussetzungen eine richterliche Rechtsfortbildung als gelungen bezeichnet werden kann. Geht man in diesem Zusammenhang von der grundsätzlichen Annahme aus, dass sich die Auslegung und Rechtsfortbildung trennen lassen, werden für diese Arbeit im wesentlichen drei Dinge relevant: Zum einen stellt sich die Frage wie Richterrecht auszulegen ist, da nur bei Klärung des konkreten Inhalts einer Entscheidung ein qualitatives Urteil ermöglicht wird. Sodann stellt sich die Frage, wie die Kriterien zu entwickeln sind. Dabei schlägt diese Arbeit Wege vor, bestehende Kriterien zu untermauern und zu präzisieren und neue Maßstäbe selbst zu entwickeln. Eine Anwendung der entwickelten Kriterien soll zum Abschluss anhand der Delisting-Rechtsprechung des BGH erfolgen.
Mit dieser Arbeit zeigt der Autor die vielfältigen Wege der politischen Willensbildung im Bundestag einschließlich außerparlamentarischer Einflussnahmen auf und misst sie speziell am Grundgesetz.
Aufgrund der Fülle der im Parlament behandelten Thematiken kann nicht jeder Abgeordnete auf jedem Gebiet über ausreichende Sachkenntnisse verfügen. Dies zieht eine Zusammenarbeit der Abgeordneten in Fraktionen und Ausschüssen sowie Kontakte zu außerparlamentarischen Dritten nach sich. Beides dient auch dazu, fremde Wissensressourcen zu erschließen. Wenngleich dies nicht die einzige Ursache für außerparlamentarische Zusammenarbeit ist, zeigt sich hieran, dass Praktiken der Kooperation nicht grundsätzlich unlauter sein können. Der Autor zeigt die Grenzen/Bedingungen der Zulässigkeit auf.
Each year, donor countries spend billions of Euros on development cooperation. Not surprisingly, a large strand of research has emerged which examines the impact of development cooperation. A sub-discipline within this strand of the literature deals with the question of whether the impact or effectiveness of development cooperation depends on the quality of the recipient country's policy and institutional environment. Over hundreds of studies have assessed this question at the macro level. In so doing, most of these studies test whether a potential effect of aid on the growth of a recipient country’s gross domestic product (GDP) is conditional on the country's policy and institutional environment. However, even after decades of research and hundreds of studies, no conclusive result has been found. One of the main reasons for the inconclusive state of the literature is that most macro-level studies have to deal with a high risk of endogeneity, treat aid as nothing but a pure income transfer, and rely on low-quality GDP data. To solve these three methodical issues, some authors have started to change the analytical focus from the macro to the micro level. Thus, these authors assess the determinants for the performance of individual development projects instead of the determinants for an effect of aid on GDP. Yet, even though the number of studies focusing on the micro level has increased steadily over the last few years, the state of the literature on the determinants for the performance of development projects still contains multiple highly relevant research gaps. The present thesis seeks to address three of these research gaps. The first research gap addressed by this thesis is related to the specific type of development cooperation. So far, nearly all existing studies focus on projects by Multilateral Development Banks. Research on the determinants for the performance of bilateral development projects is still rare. Thus, even though donors pledge to implement effective development projects, there are hardly any micro-level studies on bilateral projects. So far, only three studies use a sample which includes bilateral projects. Yet, none of the three studies assess the determinants for the performance of bilateral technical development projects. The first paper in the present thesis (GIZ paper) seeks to address this research gap by assessing the determinants for the performance of projects by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ), a bilateral state-owned aid agency active in the area of technical cooperation. The results of the paper indicate that some but not all of the existing theoretical arguments can be extended to bilateral technical projects as well.. For example, the level of market interventions in the recipient county only affects the performance of financial development projects, while the recipient country’s government capacity affects both technical and financial development projects. The paper also indicates that effects of determinants may vary among project sectors. The paper also highlights a dilemma of technical development cooperation. The countries with low government capacity are usually the ones most in need of technical cooperation projects. But, at the same time, they are also the countries in which these projects have the poorest performance The second research gap addressed by this thesis is related to one specific factor in the policy and institutional environment of recipient countries, namely corruption. This determinant is often cited as essential for project performance but has gained surprisingly little coverage in empirical studies. The few existing studies on the effect of corruption on project performance are inconclusive. Some find a statistically significant correlation, while others do not. Furthermore, so far, all existing studies use corruption perception indices as a measurement for corruption, despite the fact that these indices have well-known deficits when it comes to this research topic. One of these deficits is that such indices do not distinguish between different forms of corruption, even though it is likely that the effect of corruption will vary depending on the type of development project and form of corruption. The second paper in this thesis (Corruption paper) seeks to address this inconclusive state of the research while focusing on one specific form of corruption, namely bribery between private firms and public officials. The paper finds a small but statistically significant correlation between the corruption level and the performance of World Bank projects. The systematic effect of corruption on project performance confirms the need to consider the risk of corruption in the design and during the implementation of projects. Nonetheless, the relatively small effect of corruption and the low pseudo R-squareds advise not to overestimate the relevance of corruption for project performance. At least for the project level, the paper finds no indication that corruption is a primary obstacle to aid effectiveness. The third research gap addressed by this thesis is related to one specific sample, namely recipient countries of the International Development Association (IDA). The question of whether the policy and institutional environment affects project performance is of particular relevance for these countries, given that the World Bank's ratings on a country's policy and institutional environment decide how much IDA resources it receives. One core justification of such an allocation system is that it helps to steer more resources to places where they are most effective. However, so far, there is no conclusive empirical evidence for this statement. The only study specifically focusing on this topic, a study by the Independent Evaluation Group of the World Bank from 2010, has essential methodological limitations. The third paper of this thesis (CPR paper) seeks to address this research gap by testing whether a more refined analysis confirms the assumption of previous studies that the policy and institutional environment of IDA-recipient countries, measured by the Country Policy and Institutional Assessment ratings, has an effect on the performance of World Bank projects. Overall, neither the main regression models nor any of the robustness tests indicate a substantial correlation between the policy and institutional environment and project performance. Only for Investments Loans is the coefficient large enough to assume some effect. The overall results not only contradict the results of previous studies, but also raise strong doubts around one of the core justifications for the allocation system of the IDA. All three papers rely on a statistical large-N analysis of the performance ratings of individual development projects. These ratings are usually assigned based on the final evaluation of a project and indicate the merit or worth of an activity. The merit or worth of an activity itself is measured by criteria like relevance, effectiveness, and efficiency. In the case of the two papers on World Bank projects, the needed data stem from different databases of the World Bank. The relevant data for the GIZ paper are gathered from internal evaluation reports of the GIZ. Logistic regressions are applied as the main analytical tool. Overall, the three papers show that the policy and institutional environment of recipient countries matters for project performance, but only to a small degree and under certain circumstances. This result highlights that many researchers and practitioners tend to overestimate the role that the policy and institutional environment of recipient countries plays in project performance. Furthermore, the thesis shows that authors of future studies should consider possible interactions between project- and country-level determinants whenever possible, both in their theoretical arguments and statistical models. Otherwise, the debate on the determinants for project performance is at risk of degenerating into a statistics tournament without any connection to reality.
Despite general concern that the massive deposits of methane stored under permafrost underground and undersea could be released into the atmosphere due to rising temperatures attributed to global climate change, little is known about the methanogenic microorganisms in permafrost sediments, their role in methane emissions, and their phylogeny. The aim of this thesis was to increase knowledge of uncultivated methanogenic microorganisms in submarine and terrestrial permafrost deposits, their community composition, the role they play with regard to methane emissions, and their phylogeny. It is assumed that methanogenic communities in warmer submarine permafrost may serve as a model to anticipate the response of methanogenic communities in colder terrestrial permafrost to rising temperatures. The compositions of methanogenic communities were examined in terrestrial and submarine permafrost sediment samples. The submarine permafrost studied in this research was 10°C warmer than the terrestrial permafrost. By polymerase chain reaction (PCR), DNA was extracted from each of the samples and analyzed by molecular microbiological methods such as PCR-DGGE, RT-PCR, and cloning. Furthermore, these samples were used for in vitro experiment and FISH. The submarine permafrost analysis of the isotope composition of CH4 suggested a relationship between methane content and in situ active methanogenesis. Furthermore, active methanogenesis was proven using 13C-isotope measurements of methane in submarine permafrost sediment with a high TOC value and a high methane concentration. In the molecular-microbiological studies uncultivated lines of Methanosarcina, Methanomicrobiales, Methanobacteriacea and the Groups 1.3 and Marine Benthic from Crenarchaeota were found in all submarine and terrestrial permafrost samples. Methanosarcina was the dominant group of the Archaea in all submarine and terrestrial permafrost samples. The archaeal community composition, in particular, the methanogenic community composition showed diversity with changes in temperatures. Furthermore, cell count of methanogens in submarine permafrost was 10 times higher than in terrestrial permafrost. In vitro experiments showed that methanogens adapt quickly and well to higher temperatures. If temperatures rise due to climate change, an increase in methanogenic activity can be expected as long as organic material is sufficiently available and qualitatively adequate.
In this work, the development of a new molecular building block, based on synthetic peptides derived from decorin, is presented. These peptides represent a promising basis for the design of polymer-based biomaterials that mimic the ECM on a molecular level and exploit specific biological recognition for technical applications. Multiple sequence alignments of the internal repeats of decorin that formed the inner and outer surface of the arch-shaped protein were used to develop consensus sequences. These sequences contained conserved sequence motifs that are likely to be related to structural and functional features of the protein. Peptides representative for the consensus sequences were synthesized by microwave-assisted solid phase peptide synthesis and purified by RP-HPLC, with purities higher than 95 mol%. After confirming the desired masses by MALDI-TOF-MS, the primary structure of each peptide was investigated by 1H and 2D NMR, from which a full assignment of the chemical shifts was obtained. The characterization of the peptides conformation in solution was performed by CD spectroscopy, which demonstrated that using TFE, the peptides from the outer surface of decorin show a high propensity to fold into helical structures as observed in the original protein. To the contrary, the peptides from the inner surface did not show propensity to form stable secondary structure. The investigation of the binding capability of the peptides to Collagen I was performed by surface plasmon resonance analyses, from which all but one of the peptides representing the inner surface of decorin showed binding affinity to collagen with values of dissociation constant between 2•10-7 M and 2.3•10-4 M. On the other hand, the peptides representative for the outer surface of decorin did not show any significant interaction to collagen. This information was then used to develop experimental demonstration for the binding capabilities of the peptides from the inner surface of decorin to collagen even when used in more complicated situations close to possible appications. With this purpose, the peptide (LRELHLNNN) which showed the highest binding affinity to collagen (2•10-7 M) was functionalized with an N-terminal triple bond in order to obtain a peptide dimer via copper(I)-catalyzed cycloaddition reaction with 4,4'-diazidostilbene-2,2'-disulfonic acid. Rheological measurements showed that the presence of the peptide dimer was able to enhance the elastic modulus (G') of a collagen gel from ~ 600 Pa (collagen alone) to ~ 2700 Pa (collagen and peptide dimer). Moreover, it was shown that the mechanical properties of a collagen gel can be tailored by using different molar ratios of peptide dimer respect to collagen. The same peptide, functionalized with the triple bond, was used to obtain a peptide-dye conjugate by coupling it with N-(5'-azidopentanoyl)-5-aminofluorescein. An aqueous solution (5 vol% methanol) of the peptide dye conjugate was injected into a collagen and a hyaluronic acid (HA) gel and images of fluorescence detection showed that the diffusion of the peptide was slower in the collagen gel compared to the HA gel. The third experimental demonstration was gained using the peptide (LSELRLHNN) which showed the lower binding affinity (2.3•10-4 M) to collagen. This peptide was grafted to hyaluronic acid via EDC-chemistry, with a degree of functionalization of 7 ± 2 mol% as calculated by 1H-NMR. The grafting was further confirmed by FTIR and TGA measurements, which showed that the onset of decomposition for the HA-g-peptide decreased by 10 °C compared to the native HA. Rheological measurements showed that the elastic modulus of a system based on collagen and HA-g-peptide increased by almost two order of magnitude (G' = 200 Pa) compared to a system based on collagen and HA (G' = 0.9 Pa). Overall, this study showed that the synthetic peptides, which were identified from decorin, can be applied as potential building blocks for biomimetic materials that function via biological recognition.
One of the most significant current discussions in Astrophysics relates to the origin of high-energy cosmic rays. According to our current knowledge, the abundance distribution of the elements in cosmic rays at their point of origin indicates, within plausible error limits, that they were initially formed by nuclear processes in the interiors of stars. It is also believed that their energy distribution up to 1018 eV has Galactic origins. But even though the knowledge about potential sources of cosmic rays is quite poor above „ 1015 eV, that is the “knee” of the cosmic-ray spectrum, up to the knee there seems to be a wide consensus that supernova remnants are the most likely candidates. Evidence of this comes from observations of non-thermal X-ray radiation, requiring synchrotron electrons with energies up to 1014 eV, exactly in the remnant of supernovae. To date, however, there is not conclusive evidence that they produce nuclei, the dominant component of cosmic rays, in addition to electrons. In light of this dearth of evidence, γ-ray observations from supernova remnants can offer the most promising direct way to confirm whether or not these astrophysical objects are indeed the main source of cosmic-ray nuclei below the knee. Recent observations with space- and ground-based observatories have established shell-type supernova remnants as GeV-to- TeV γ-ray sources. The interpretation of these observations is however complicated by the different radiation processes, leptonic and hadronic, that can produce similar fluxes in this energy band rendering ambiguous the nature of the emission itself. The aim of this work is to develop a deeper understanding of these radiation processes from a particular shell-type supernova remnant, namely RX J1713.7–3946, using observations of the LAT instrument onboard the Fermi Gamma-Ray Space Telescope. Furthermore, to obtain accurate spectra and morphology maps of the emission associated with this supernova remnant, an improved model of the diffuse Galactic γ-ray emission background is developed. The analyses of RX J1713.7–3946 carried out with this improved background show that the hard Fermi-LAT spectrum cannot be ascribed to the hadronic emission, leading thus to the conclusion that the leptonic scenario is instead the most natural picture for the high-energy γ-ray emission of RX J1713.7–3946. The leptonic scenario however does not rule out the possibility that cosmic-ray nuclei are accelerated in this supernova remnant, but it suggests that the ambient density may not be high enough to produce a significant hadronic γ-ray emission. Further investigations involving other supernova remnants using the improved back- ground developed in this work could allow compelling population studies, and hence prove or disprove the origin of Galactic cosmic-ray nuclei in these astrophysical objects. A break- through regarding the identification of the radiation mechanisms could be lastly achieved with a new generation of instruments such as CTA.