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This article considers how different legal systems treat shareholder loans on corporate insolvency, looking at the approach of Germany, England, the US and Austria.

The flow structures in a circular-disk-generated recirculation wake with a centrally flushing jet were studied by the smoke-wire and schlieren flow visualization techniques. The smoke-wire was applied to the low velocity regime to reveal the detailed vortex structures in the recirculation bubble, whilst the schlieren technique was employed in the high velocity regime to show the characteristics of the penetration and mixing. The smoke and schlieren photographs show prominent features of the interaction between the central jet and the recirculation flow. Comprehensive flow patterns and the behavior in each characteristic flow regime were investigated. Four typical characteristic flow regimes, pre-penetration, transition, penetration, and no-recirculation, were identified for different jet velocities in the near wake region. The shear and mixing processes were found to be different in each regime. Density effects on the formation of recirculation are discussed. The contours of the separation surfaces and the lengths of the recirculation zone are correlated with nondimensional parameters. The recirculation length reaches a maximum in the transition region, and shortens with increasing central-to-annular jet velocity ratio in the penetration region.

Relaxin-like peptides (RLN/INSL) play diverse roles in reproductive and neuroendocrine processes in placental mammals and are functionally associated with two distinct types of receptors (RXFP) for each respective function. The diversification of RLN/INSL and RXFP gene families in vertebrates was predominantly driven by whole genome duplications (2R and 3R). Teleosts preferentially retained duplicates of genes putatively involved in neuroendocrine regulation, harboring a total of 10-11 receptors and 6 ligand genes, while most mammals have equal numbers of ligands and receptors. To date, the ligand-receptor relationships of teleost Rln/Insl peptides and their receptors have largely remained unexplored. Here, we use selection analyses based on sequence data from 5 teleosts and qPCR expression data from zebrafish to explore possible ligand-receptor pairings in teleosts. We find support for the hypothesis that, with the exception of RLN, which has undergone strong positive selection in mammalian lineages, the ligand and receptor genes shared between mammals and teleosts appear to have similar pairings. On the other hand, the teleost-specific receptors show evidence of subfunctionalization. Overall, this study underscores the complexity of RLN/INSL and RXFP ligand-receptor interactions in teleosts and establishes theoretical background for further experimental work in nonmammals.

This thesis explores the necessity for bovine tuberculosis (bTB) eradication; considers the use the tuberculin test as a tool in bTB eradication and explores the need to select the optimal test methodology, to evaluate outcomes of existing procedures and to progressively modify aspects of a bTB eradication programme. Tuberculosis remains a significant disease of animals and humans worldwide. The mycobacteria which cause bTB have an extremely wide host range and serious, although currently probably under-diagnosed, zoonotic potential. Where bTB controls are effective, clinical cases are infrequent in cattle and human zoonotic TB is uncommon. The design of a bTB control or eradication programme should, take into consideration fundamental scientific and veterinary knowledge, the inherent strengths and limitations of the test, the epidemiological profile of disease, non-bovine maintenance hosts and the experience of other eradication programmes. Programme managers need to be mindful of the necessity for robust quality control: including tuberculin assay, monitor of test performance and other surveillance protocols, and assessment of herd health and other bio-security practices. Continuous and rational evaluation of policy efficacy, constraints to progress, optimal desirable goals and appropriate policy adaptations requires data and epidemiological analysis capability. The Irish national bTB eradication programme is utilised in this thesis as an example of science informed policy in a national context. The studies reported were representative of an ongoing monitor and evaluation process of the quality of aspects of tuberculin, the tuberculin test and the continued re-evaluation of existing policy protocols. Tuberculin tests are safe to use and continue to be the primary tool in bTB eradication programmes with the choice of tuberculin test determined by the ecosystem in which it will be used. This thesis assesses the impact of different potencies of bovine tuberculin on the comparative tuberculin test (SICTT) and the single intradermal test (SIT). It also compares the performance of tuberculin from different manufacturers. There was a significant difference in the number of reactors detected using high and low potency tuberculin but no apparent impact if the supplier/manufacturer was changed provided the potency remained constant. However, potency estimates from guinea pig bio-assay conducted during these studies were imprecise. Two examples of policy review exercises forming part of the quality control assessment on the outputs of the SICTT are provided. These affirm the reliability of the SICTT, in Ireland, at current levels of bTB infection and demonstrate that the Irish depopulation policy for bTB (depopulation, disinfection, contiguous testing and local badger removal where implicated) is successful in enabling herds attain and retain bTB freedom following restocking. In conclusion control and eradication of tuberculosis in cattle is a desirable objective for animal welfare, socio-economic and zoonotic reasons. Tuberculin potency is critical to test performance affecting both test sensitivity and specificity and therefore, the accurate determination of potency is particularly important. In the future, as now, eradication of bTB will undoubtedly continue to require a multifaceted approach if it is to be successful.

It is widely believed that synaptic plasticity may provide the neural mechanism that underlies certain kinds of learning and memory in the mammalian brain. The expression of long-term potentiation (LTP) in the hippocampus, an experimental model of synaptic plasticity, requires the GluR-A subunit of the AMPA subtype of glutamate receptor. Genetically modified mice lacking the GluR-A subunit show normal acquisition of the standard, fixed-location, hidden-platform watermaze task, a spatial reference memory task that requires the hippocampus. In contrast, these mice are dramatically impaired on hippocampus-dependent, spatial working memory tasks, in which the spatial response of the animal is dependent on information in short-term memory. Taken together, these results argue for two distinct and independent spatial information processing mechanisms: (i) a GluR-A-independent associative learning mechanism through which a particular spatial response is gradually or incrementally strengthened, and which presumably underlies the acquisition of the classic watermaze paradigm and (ii) a GluR-A-dependent, non-associative, short-term memory trace which determines performance on spatial working memory tasks. These results are discussed in terms of Wagner's SOP model (1981).

The malaria parasite, Plasmodium yoelii 17X, causes a self-limited, nonlethal infection characterized, in the blood stage, by preferential invasion of reticulocytes. Previous studies have suggested that immunity to the blood stage infection may be related to enhanced levels of class I MHC Ag on the parasitized reticulocyte surface and can be adoptively transferred to immunodeficient mice by immune CD8+ T cells in the absence of CD4+ T cells. To further examine the mechanisms of CD8+ T cell involvement in immunity to blood stage P. yoelii infection, we performed in vivo CD8 depletion and adoptive transfer experiments. Depletion of CD8+ T cells during primary blood stage infection in BALB/c mice did not diminish the ability of the mice to resolve their infections. Spleen cells from immune BALB/c and C57BL/10 mice were transferred to BALB/c-nu/nu and C57BL/10-nu/nu mice, respectively. The recipient mice were CD4 depleted in vivo to kill any transferred CD4+ T cells. The mice failed to control the infection. Populations of CD4-, CD8+ T cells were transferred from immune CBA/CaJ donors to in vivo CD4-depleted CBA/CaJ recipients. The mice were unable to control the infection. Although immune unfractionated spleen cells transferred rapid protection in all three mouse strains and immune CD4+ T cells transferred immunity in the two mouse strains studied, CD8+ T cells by themselves were neither protective nor did they enhance immunity.