A breed-and-burn molten salt reactor (BBMSR) concept is proposed to address the Generation IV fuel cycle sustainability objective in a once-through cycle with low enrichment and no reprocessing. The BBMSR uses separate fuel and coolant molten salts, with the fuel contained in assemblies of individual tubes that can be shuffled and reclad periodically to enable high burnup. In this dual-salt configuration, the BBMSR may overcome several limitations of previous breed-and-burn (B$\&$B) designs to achieve high uranium utilisation with a simple, passively safe design. A central challenge in design of the BBMSR fuel is balancing the neutronic requirement of large fuel volume fraction for B$\&$B mode with the thermal-hydraulic requirements for safe and economically competitive reactor operation. Natural convection of liquid fuel within the tubes aids heat transfer to the coolant, and a systematic approach is developed to efficiently model this complex effect. Computational fluid dynamics modelling is performed to characterise the unique physics of the system and produce a new heat transfer correlation, which is used alongside established correlations in a numerical model. A design framework is built around this numerical model to iteratively search for the limiting power density of a given fuel and channel geometry, applying several defined temperature and operational constraints. It is found that the trade-offs between power density, core pressure drop, and pumping power are lessened by directing the flow of coolant downwards through the channel. Fuel configurations that satisfy both neutronic and thermal-hydraulic objectives are identified for natural, 5$\%$ enriched, and 20$\%$ enriched uranium feed fuel. B$\&$B operation is achievable in the natural and 5$\%$ enriched versions, with power densities of 73 W/cm$^3$ and 86 W/cm$^3$, and theoretical uranium utilisations of 300 $\mathrm{MWd/kgU_{NAT}}$ and 25.5 $\mathrm{MWd/kgU_{NAT}}$, respectively. Using 20$\%$ enriched feed fuel relaxes neutronic constraints so a wider range of fuel configurations can be considered, but there is a strong inverse correlation between power density and uranium utilisation. The fuel design study demonstrates the flexibility of the BBMSR concept to operate along a spectrum of modes ranging from high fuel utilisation at moderate power density using natural uranium feed fuel, to high power density and moderate utilisation using 20$\%$ uranium enrichment.

A dog owner does not only have rights, but also (and mainly) a lot of obligations. One of the aims of this work was to look at different areas concerning the ownership (holding) of a dog in relation to the actual public law regulations. Particular chapters reflect possible life situations, which have (especially from a point of view of public law) an effect on coexistence with a dog and (often negative) the impact (penalties) for a dog holder. Thematic areas are addressed, for example, purchasing a dog, his vaccination and other health and life conditions, the possibility of shortening a tail or ears, the admissible conditions and methods that permit the killing of a dog or the conditions and ways to bury a dog. Further mention is made of the possibilities of travelling with a dog (and also abroad), also described are the law regulations of dog fees and the generally binding ordinances of municipalities. Deeper consideration was essential in respect of the areas concerning misdemeanours and criminal offences, which can be commited both on a dog and by a dog (incl. veterinarian demands or animal cruelty). There are follow-up chapters concerning liability for damage and compensation for damage. A part of the work is dedicated to breed specific legislation concerning breeding some (so called "fighting" or...