This dissertation focuses on the spectroscopic and thermodynamic characterization of the unusual metal-RNA cluster found in the P5abc subdomain of the Tetrahymena group I intron. The P5abc subdomain is a part of the P4-P6 domain found in the Tetrahymena thermophila group I intron selfsplicing RNA. From both X-ray crystal structures of the P4-P6 domain, a remarkable cluster of Mg2+ or Mn2+ ions was found in the P5abc subdomain (Cate et al. 1996; Juneau et al. 2001). It is believed that the metal ion core in the P5abc subdomain stabilizes the active conformation of the RNA (Cate et al. 1996). An understanding of the role of these metal ions in facilitating the correct structure of the P5abc subdomain provides insight into how metal ions help overcome the folding barriers of complex RNA structures. Under solution conditions, the properties of this uncommon metal ion core and its influence on the truncated P5abc subdomain structure have been investigated. Both EPR spectroscopy and thermal denaturation experiments have been employed to search for a spectroscopic signature of metal ion core formation and also determine the thermodynamic contribution of the metal ion core on the stability of the folded P5abc structure. A spectroscopic signature of metal ion core formation was assigned for the P5abc subdomain by EPR microwave power saturation studies. Power saturation studies of the P5abc subdomain, P4-P6 domain and corresponding mutants reveal that the addition of 5 equivalents of Mn2+ are required for the wild type P5abc subdomain to form the metal ion core under solution conditions in 0.1 M NaCl. Results from both domain and subdomain microwave power saturation studies suggest that this technique can be applied for detecting clustering of Mn2+ ions in other RNA structures. The thermodynamic consequence of this metal ion core was probed by thermal denaturation techniques including UV-Vis spectroscopy and differential scanning calorimetry (DSC). DSC experiments were utilized to directly determine the thermodynamic contribution of the metal ion core. This value was determined to be an average of ∆∆G of -5.3 kcal/mol and is consistent with ∆∆G values obtained for other RNA tertiary structures.

The structure and function of RNA molecules are dependent on RNA-metal ion interactions in both diffusive and direct ways. Structural information for RNA has been obtained using various biophysical and biochemical methods. In this study, using site-directed spin labeling (SDSL) and EPR spectroscopy, distances in RNA duplexes, TAR RNA, and the hammerhead ribozyme have been measured to investigate RNA structures. Kinetic measurements have been performed in the extended hammerhead ribozyme to correlate the catalytic function with metal dependent ribozyme folding. As a basic model system for distance measurements, inter-spin distances in RNA duplexes with spin labels at various positions are measured using SDSL with continuous EPR and a Fourier deconvolution method. Divalent metal-ion dependent TAR RNA folding from bent to extended conformers is monitored by measuring inter-spin distances near the bulge region. In order to investigate a proposed loop-loop interaction in the extended hammerhead ribozyme which significantly enhances the ribozyme activity, distance measurements, dynamics studies, and kinetics measurements have been performed. We have introduced PELDOR long-distance measurements in order to investigate metal dependent folding of the hammerhead ribozyme. The dynamics of the spin labels attached to the hammerhead ribozyme with increasing mono- and divalent metal ion concentrations are monitored using CW EPR spectroscopy at room temperature. EPR data show that a loop-loop interaction occurs near the U1.6 nucleotide, and that in 0.1 M NaCl the docking occurs at submillimolar Mg2+ concentrations ([Mg2+]1/2, docking = ~ 0.7 mM). Kinetics measurements show that the hammerhead ribozyme requires high concentration of Mg2+ for the maximum cleavage activity ([Mg2+]1/2, cleavage = ~ 90 mM).

Abstract Methyl Viologen is a kind of organic molecular magnet of current interest which comprises with organic radicals (unpaired electrons). The molecular formula of the sample is (C12H14N2)2+X2-, where ¡§X2-¡¨ denotes a non-magnetic anion (CdI42-, I3-I- etc.). We perform the magnetization (using SQUID magnetometer) and electron paramagnetic resonance (EPR) measurements. Two absorption peaks are observed in EPR spectrum indicating that there are two radical forms in our samples. One of the radicals exists in every sample having the g1-factor value 2.004. The other radical which has the g2-factor 2.001 exists only in certain samples. Interestingly, we find that these samples exhibit ferromagnetism at room temperature. We use Lorentzian profile to quantitatively analyze the EPR spectrum of the samples and derive the ratio (A2/A1) of two different absorption peaks, which represents the amount of g2 radical. The remanent magnetization and saturation magnetization are found to increase as the ratio value increases, indicating that the strength of ferromagnetism is strongly correlated with g2 radical.

Nous nous intéressons à l'effet des fonds d'ondes gravitationnelles sur la polarisation de la lumière et aux conséquences induites sur des systèmes dans lesquels l'information est portée par la polarisation de photons. A cet effet, nous construisons l'approximation eikonale sur un espace courbe et étudions l'évolution des objets obtenus dans un bain d'ondes gravitationnelles. Nous développons alors un formalisme géométrique permettant de construire efficacement les observables physiques associées à un système optique, puis d'exprimer et d'évaluer ces observables en fonction des perturbations gravitationnelles. Nous montrons ainsi que pour des dispositifs de type EPR où l'évolution de la phase n'affecte pas les mesures, l'effet des ondes gravitationnelles sur les polarisations des photons est trop faible pour détruire les corrélations ce qui garantit la possibilité d'utiliser des corrélations EPR dans le cadre de communications spatiales.

The quest for sustainable development has always involved the complex task of reconciling the need for socio-economic development with public health and environmental protection. This challenge has often emerged in the trade and environment debate but has most recently been evident in international trade in used electrical and electronic equipment (UEEE). While international trade in UEEE provides means for socio-economic development in the developing world, it also serves as a conduit for transboundary dumping of e-waste in the developing world giving rise to serious health and environmental concerns. This research investigates the socio-economic as well as health and environmental impacts of international trade in UEEE in two developing countries – Nigeria and Ghana. The research identifies a major loophole in the existing international legal framework as the primary factor responsible for e-waste dumping in the developing world. This loophole relates to the absence of a legal framework for differentiating between functional UEEE and junk e-waste. This has resulted in both functional UEEE and junk e-waste being concurrently shipped to the developing world as “used electrical and electronic equipment”. The research proposes two policy frameworks for addressing this problem. On the part of developing countries, the research proposes a trade policy framework crafted in line with WTO rules. This framework will entail the development of an international certification system which will serve to differentiate functional used electronics from junk e-waste. While the former may be eligible for import, the research proposes an import ban on the latter. On the part of developed countries, the research proposes the development of a policy framework which regulates the toxic and hazardous substances that go into the production of electrical and electronic equipment as well as enhance their reusability and recyclability at end-of-life. The framework should take into consideration the entire life cycle of the products from the design stage to end-of-life. The research argues that the implementation of this design framework will go a long way in reducing the health and environmental impacts of such equipment when subsequently shipped to the developing world at end-of-life.

A mutation (CTG to TTG) of FeSOD gene was found in Escherichia coli. Since they both encode leucine, it is a silent mutation. Site-­‐directed mutagenesis was applied to correct the mutation, and the mutant FeSOD (before gene correction) and wild type FeSOD (after gene correction) were purified. The FeSODs from the two genes were Characterized using different assays and spectroscopic methods including EPR and CD. The requirement for the rare codon TTG may result in slowed translation and heavy demand on a scarce tRNA. Cultures expressing wild type FeSOD are better able to grow for long times after addition of IPTG and more mature to incorporate Fe atoms to the active sites than are cultures expressing the mutant gene. Moreover, the wild type FeSOD has more activity than the mutant. To our knowledge, this is the first time that a silent mutation has been demonstrated to affect metal incorporation into a metalloenzyme.

Australia has a crop research system with higher research intensity than exists internationally. Motivated to improve R&D policy in Canada, this dissertation focuses on the Australian End Point Royalty (EPR) system for wheat and addresses four principal questions: (1) How was the Australian system created and how does it work? (2) How do public, producer and private ownership of breeding programs affect the pricing of varieties? (3) How do EPR rates affect wheat variety adoption? (4) Finally, how would uniform EPR rates, similar to those used in France, affect variety selection, total production and revenue if used in the Australian market? In addressing the first question I use existing literature and interviews with prominent personnel in the Australian wheat breeding system, including management of InterGrain, AGT, DAFWA, GRDC and others. Interviews were conducted during field study in Australia in 2011. In addressing the second question I employ a horizontal location model to analyze three game theoretic scenarios of a two firm oligopoly market with private, public and producer owned-breeding companies. The results show public and producer ownership of one of the wheat breeding programs reduces price level relative to private only ownership. I derive a novel result showing that when competing with private firms who must price above marginal cost, the public firm should also price above marginal cost in order to maximize total industry surplus. In addressing the third question I develop and estimate an econometric wheat variety adoption model for Western Australia. I find EPR rates have a negative inelastic, statistically significant impact on the adoption of varieties. Finally, in addressing the last question, I use the econometric model to simulate the adoption of Australian wheat varieties, given a counterfactual of revenue neutral uniform EPR rates. The uniform EPR rates speed up both the adoption and dis-adoption of varieties, thereby increasing weighted average yield and total production. The value of the increase in value of production exceeds the revenue for breeders under varying EPR rates, suggesting uniform EPR system may be an attractive alternative to varying EPR rates.

Many countries have formulated their eHealth visions and billions of dollars have been spent on supporting the eHealth development throughout the world. An important part of the development is the electronic patient record (EPR). To enable sharing and increase cooperation between care providers, most Swedish county councils have decided to use a region-wide EPR. The health professionals often experience numerous problems and consider the region-wide EPR to be too generic and require them to tailor their practices instead of the system evolving towards supporting their needs. The aim of the PhD research is to gain knowledge of adoption when deploying and using region-wide health IT systems. This is accomplished by studying, analysing and reflecting upon what region-wide health IT systems are and how professionals use them in their practice. In the research a grounded theory method has been used, which means that the empirical data, not theories and hypotheses, have driven the research process. The data-gathering methods have been interviews, observations, participating in meetings, questionnaires, seminars and conducting literature reviews. In order to be able to improve the adoption, a set of four key principles has been identified: (1) Evolving systems-Engaged users, (2) Treat IT deployment and usage as part of organisational development, (3) Identify, respect and support differences, and (4) Identify what must be customised and what can be centralised. These four principles challenge the traditional way of developing enterprise-wide IT and emphasise the importance that users must engage in the development, procurement and deployment process to identify their similar and unique needs and procedures. It is crucial that both the similarities and uniqueness are respected and supported. The similarities can be supported by a centralised, standardised solution, while uniqueness requires a customised solution. In order to accomplish that, the IT deployment and usage needs to be treated as an important part of the on-going organisational development, and the IT systems must evolve, i.e., be continuously developed in order to engage the users to participate.

The quest for sustainable development has always involved the complex task of reconciling the need for socio-economic development with public health and environmental protection. This challenge has often emerged in the trade and environment debate but has most recently been evident in international trade in used electrical and electronic equipment (UEEE). While international trade in UEEE provides means for socio-economic development in the developing world, it also serves as a conduit for transboundary dumping of e-waste in the developing world giving rise to serious health and environmental concerns. This research investigates the socio-economic as well as health and environmental impacts of international trade in UEEE in two developing countries – Nigeria and Ghana. The research identifies a major loophole in the existing international legal framework as the primary factor responsible for e-waste dumping in the developing world. This loophole relates to the absence of a legal framework for differentiating between functional UEEE and junk e-waste. This has resulted in both functional UEEE and junk e-waste being concurrently shipped to the developing world as “used electrical and electronic equipment”. The research proposes two policy frameworks for addressing this problem. On the part of developing countries, the research proposes a trade policy framework crafted in line with WTO rules. This framework will entail the development of an international certification system which will serve to differentiate functional used electronics from junk e-waste. While the former may be eligible for import, the research proposes an import ban on the latter. On the part of developed countries, the research proposes the development of a policy framework which regulates the toxic and hazardous substances that go into the production of electrical and electronic equipment as well as enhance their reusability and recyclability at end-of-life. The framework should take into consideration the entire life cycle of the products from the design stage to end-of-life. The research argues that the implementation of this design framework will go a long way in reducing the health and environmental impacts of such equipment when subsequently shipped to the developing world at end-of-life.

This thesis presents a whole-core benchmark of the European Pressurized Reactor (EPR) using multiple transport methods. The core specifications were taken directly from the Final Safety Analysis Report (FSAR) submitted to the Nuclear Regulatory Commission (NRC) and the reactor was modeled in a stylized manner while maintaining full heterogeneity at the pin and assembly level. The geometry and material specifications are given as well as problem-specific cross sections for 2, 4, and 8 energy group calculations. Cross sections were generated using HELIOS, a lattice depletion code based on the Collision Probability Method (CPM). The multi-group cross sections were utilized in the reference calculation, COMET calculation, and response function generation. The reference solution was obtained via an MCNP model identical to the one implemented in COMET. Specific steps towards constructing and running a COMET calculation are outlined. Detailed results including assembly eigenvalues, core eigenvalues, and pin fission densities are presented.