Super heavy nuclei provide opportunities to study nuclear structure near three simultaneous limits: in charge Z, spin I and excitation energy E∗. These nuclei exist only because of a fission barrier, created by shell effects. It is therefore important to determine the fission barrier and its spin dependence Bf(I), which gives information on the shell energy Eshell(I). Theoretical calculations predict different fission barrier heights from Bf(I = 0) = 6.8 MeV for a macro-microscopic model to 8.7 MeV for Density Functional Theory calculations using the Gogny or Skyrme interactions. Hence, a measurement of Bf provides a test for theories.To investigate the fission barrier, an established method is to measure the rise of fission with excitation energy, characterized by the ratio of decay widths Γfission/Γtotal, using transfer reactions. However, for heavy elements such as 254No, there is no suitable target for a transfer reaction. We therefore rely on the complementary decay widths ratio Γγ/Γfission and its spin dependence, deduced from the entry distribution (I, E∗).Measurements of the gamma-ray multiplicity and total energy for 254No have been performed with beam energies of 219 and 223 MeV in the reaction 208Pb(48Ca,2n) at ATLAS (Argonne Tandem Linac Accelerator System). The 254No gamma rays were detected using the Gammasphere array as a calorimeter - as well as the usual high resolution γ-ray detector. Coincidences with evaporation residues at the Fragment Mass Analyzer focal plane separated 254No gamma rays from those from fission fragments, which are > 10^6 more intense. From this measurement, the entry distribution - i.e. the initial distribution of I and E∗ - is constructed. Each point (I,E∗) of the entry distribution is a point where gamma decay wins over fission and, therefore, gives information on the fission barrier.The measured entry distributions show an increase in the maximum spin and excitation energy from 219 to 223 MeV of beam energy. The distributions show a saturation of E∗ for high spins. The saturation is attributed to the fact that, as E∗ increases above the saddle, Γfission rapidly dominates. The resulting truncation of the entry distribution at high E∗ allows a determination of the fission barrier height.The experimental entry distributions are also compared with entry distributions calculated with decay cascade codes which take into account the full nucleus formation process, including the capture process and the subsequent survival probability as a function of E∗ and I. We used the KEWPIE2 and NRV codes to simulate the entry distribution.

During the last years, drugs that prolong the repolarisation phase of the myocardial action potential, due to inhibition of the rapid component of the delayed-rectifying potassium channel (IKr) have been in focus. In addition to arrhythmogenic potential, selective Ikr-blockers have also been shown to be embryotoxic and teratogenic in animal studies. The aim of this thesis was to investigate a theory that these developmental toxic results from pharmacologically induced episodes of embryonic cardiac arrhythmias leading to hypoxia related damage in the embryo. Almokalant (ALM) was used as a model compound for selective Ikr-blockers. ALM induced embryonic cardiac arrhythmia, and in similarity with results obtained by maternal hypoxia, ALM induced embryonic death and growth retardation in both rats, and mice. The theory of a hypoxia-related mechanism was strengthened by the results that ALM induce phase specific external and visceral defects (e.g. cleft lip/palate, distal digital, cardiovascular, and urogenital defects), and that the skeletal defects (not shown before) showed a clear trend; the later the treatment the more caudal was the site of the defect, which is in accordance with results from maternal hypoxia induced by e.g. lowering of the O2 content in the air. The spin trapping agent PBN decreased almokalant induced malformations, suggesting that the defects mainly are caused by reoxygenation damage after episodes of severe embryonic dysrhythmia, rather than "pure hypoxia". Sotalol was tested in a third species, the rabbit who expresses functional IKr channels both in the embryo and in the adult, where it induced developmental toxicity, and indicating that the embryo is more sensitive than the adult towards arrhythmia caused by IKr-blockers.

Timely student completion of undergraduate nursing programs in order to produce practicing registered nurses (RNs) is of concern to students, faculty, governments, employers, and health care consumers across Canada. The shortage of health care professionals in Saskatchewan, particularly in nursing, is an immediate and growing concern. The average age of RNs in Saskatchewan is 44.9 years (CIHI, 2003). With the inevitability of retirement of many RNs, recruitment and retention of new nurses is critical to the quality of health care in this province. The looming shortage creates a further challenge for key stakeholders in academia, government, and health regions who hold a vested interest in the retention of nurses educated in Saskatchewan. Currently, little is known about the impact of barriers to timely completion of students in the Nursing Education Program of Saskatchewan (NEPS). Considering the aging nursing workforce, frequent, substantial numbers of nursing graduates are important to meet the demand for health human resources in the province of Saskatchewan (SRNA, 2004). <p>The purpose of this research was to conduct a secondary analysis of the NEPS Database including exit surveys completed by 363 graduates over a three-year period, 2002-2003; 2003-2004; 2004-2005. Group membership was determined by splitting data between graduates who had taken four academic years (September to April) or less to complete the program (timely completers) and those who took longer than four academic years (delayed completers). Objectives were to examine the differences between the two aforementioned groups in terms of the following variables: employment hours, financial burden, student loan status, dollar amount of bursaries awarded during the NEPS, primary responsibility the year prior to the NEPS, significant life changes during the NEPS, Aboriginal ancestry and core course averages. <p>Results show that 86% of females in the study group completed the NEPS in a timely manner compared with 58% of their male counterparts. There was a trend of higher employment hours per week in every year of the NEPS for delayed completers. However, this difference approached statistical significance only for students in year one, t (360) = 1.81, p < .07. Fifty percent of delayed completers had three or more significant life changes during the NEPS. Seventy-five percent of timely completers had two or fewer significant life changes. Students require various forms of support to ensure timely completion of the NEPS. It is anticipated that results of this research will inform policy decisions to facilitate timely completion of the NEPS.

Two studies on potential approaches for processing low-salt, low-fat (LSLF) bologna were completed. In study 1, the effects of three factors, namely salt type (sea salt vs. regular NaCl), NaCl concentration (0.75%, 1.00%, 1.25% and 2.00%) and holding of stuffed batter before cooking (cooked immediately (CI) vs. delayed cooking (DC)), on the quality of LSLF bologna were investigated. There was no difference between salt type for most of the parameters measured. The holding factor significantly improved the water holding capacity (WHC) and texture of bologna samples containing 0.75% NaCl, as shown by lower (p<0.05) expressible moisture. However, holding factor did not affect WHC and instrumental texture of samples with 1.00%, 1.25% or 2.00% NaCl. A NaCl level by hold effect (p<0.05) was observed for texture profile analysis (TPA) in which there was significant improvement in the texture of samples containing 0.75% NaCl that were subjected to DC, but no effect at other NaCl levels. Panelists were able to detect the positive effect (p<0.05) of DC on the texture of samples with 0.75% or 1.00% NaCl. This study showed that DC is effective in improving the texture of bologna samples with extremely low NaCl (0.75%) content. The biggest challenge in this first study was the difficult sample handling experienced during slicing. Since bologna is commonly sold as thin slices, the bologna must be firm enough for ease of slicing. The second study focused on improving bologna firmness by the addition of microbial transglutaminase (MTG), known for its functionality as a protein cross-linker, and of flaxseed meal (FSM), known for its excellent water holding capacity. The physico-chemical and sensory characteristics of 12 treatment combinations (0, 0.15% and 0.30% MTG; 0, 0.5%, 1.0% and 1.5% FSM) were determined. In general, results showed that MTG significantly improved the textural quality of bologna, but resulted in a higher purge loss during storage of vacuum packaged slices. On the other hand, FSM significantly reduced the expressible moisture content and purge loss of the product. In terms of product colour, MTG had no effect but FSM when added to the formulation at level as low as 0.5%, affected the colour as determined by both instrumental and sensory evaluation. The overall results of the project indicated that texture in LSLF bologna is not a major issue, since processing conditions and combinations of ingredients can be manipulated to improve texture. The biggest challenge, however, is in the area of flavour – improving the flavour of low-salt processed meats warrants further research.

A combined experimental and analytical program was conducted to investigate the effects of Alkali-Silica Reaction (ASR) and Delayed Ettringite Formation (DEF) on D-regions in reinforced concrete (RC) bridge bents. Four large-scale RC specimens, which represent cantilever and straddle bents in Texas bridges in each specimen, were constructed. The first specimen represented the unexposed control specimen, while the other three were conditioned in the field with supplemental watering to promote ASR/DEF and served as the exposed specimens. The control and two exposed specimens with various levels of ASR/DEF, after eight months and two years of field conditioning, were load tested to failure. The last specimen remains in field with additional exposure to promote ASR/DEF and will be load tested in future studies. The width and length of preload-induced cracks and developing cracks that initiated in the exposed specimens and grew over time, indicating concrete expansion due to ASR/DEF mechanisms, were measured. Petrographic analysis results of concrete cores extracted from the exposed specimens after their load testing confirmed the formation of ASR gel and minimum accumulation of ettringite. The structural testing results showed that the failure mechanism in all three tested specimens was due to a brittle shear failure in the beam-column joint. However, slightly greater stiffness, strength, and ductility were observed in the exposed specimens as a result of the activation of the reinforcing steel in the specimens due to the expansion of the concrete primarily from ASR, which effectively prestressed and confined the core concrete. Sectional analysis and Strut-and-Tie Modeling (STM) of the experimental specimens were applied. Three-dimensional nonlinear Finite Element Analyses (FEA) were also conducted to numerically simulate the overall structural performance, internal response, and out-of-plane behavior of the experimental specimens. The effects of varying constitutive relations of the concrete in tension on models of the specimens were compared with the measured experimental response. A method to mimic ASR/DEF effects on exposed specimens was proposed and incorporated into the FEA approach. As a result, forces that prestress and confine the core concrete were effectively applied through the reinforcing steel prior to subsequent structural loading. The three-dimensional FEA approach was able to simulate the out-of-plane behavior of the beam-column joint and the proposed method yielded comparable results with the measured overall and internal behavior of specimens.

Today, except for mathematical operations, our brain functions much faster and more efficient than any supercomputer. It is precisely this form of information processing in neural networks that inspires researchers to create systems that mimic the brain’s information processing capabilities. In this thesis we propose a novel approach to implement these alternative computer architectures, based on delayed feedback. We show that one single nonlinear node with delayed feedback can replace a large network of nonlinear nodes. First we numerically investigate the architecture and performance of delayed feedback systems as information processing units. Then we elaborate on electronic and opto-electronic implementations of the concept. Next to evaluating their performance for standard benchmarks, we also study task independent properties of the system, extracting information on how to further improve the initial scheme. Finally, some simple modifications are suggested, yielding improvements in terms of speed or performance.

Main focus is to extend the analysis of the ruin related quantities, such as the surplus immediately prior to ruin, the deficit at ruin or the ruin probability, to the delayed renewal risk models. First, the background for the delayed renewal risk model is introduced and two important equations that are used as frameworks are derived. These equations are extended from the ordinary renewal risk model to the delayed renewal risk model. The first equation is obtained by conditioning on the first drop below the initial surplus level, and the second equation by conditioning on the amount and the time of the first claim. Then, we consider the deficit at ruin in particular among many random variables associated with ruin and six main results are derived. We also explore how the Gerber-Shiu expected discounted penalty function can be expressed in closed form when distributional assumptions are given for claim sizes or the time until the first claim. Lastly, we consider a model that has premium rate reduced when the surplus level is above a certain threshold value until it falls below the threshold value. The amount of the reduction in the premium rate can also be viewed as a dividend rate paid out from the original premium rate when the surplus level is above some threshold value. The constant barrier model is considered as a special case where the premium rate is reduced to $0$ when the surplus level reaches a certain threshold value. The dividend amount paid out during the life of the surplus process until ruin, discounted to the beginning of the process, is also considered.

Hybrid Make-To-Stock (MTS)-Make-To-Order (MTO) manufacturing is a well known policy that captures the benefits of both MTS and MTO policies. This manufacturing policy is adopted by many manufacturing firms because it allows for production based on customer specifications while keeping short response times. We study a hybrid MTS-MTO manufacturing system which consists of two processing stages and an intermediate buffer between these two stages. We propose two separate scenarios for ordering and replenishment of components from the first stage which will give more realistic guidance for practitioners. The first scenario is batching customer orders before being released to the first stage. The second scenario is batch replenishment of common components from the first stage. Most existing MTS-MTO models focus on one-for-one ordering and replenishment strategies. We enhance these models by introducing a batch ordering policy to account for economies of scale in ordering when there is an ordering cost associated with each order placed for common components. We use queueing theory to model the system behavior and use the matrix-geometric method to evaluate system performance under the new ordering policy. Afterwards, we develop an optimization model with the objective to minimize the system overall costs. The purpose of our optimization model is to find the optimal intermediate buffer size and the optimal order quantity for the system. In the second scenario, we introduce the batch replenishment policy from stage 1. This policy is suitable when stage 1 and stage 2 are physically distant and there is a shipping cost incurred when components are transferred from stage 1 to stage 2. The decision variables in this model are the intermediate buffer size and the shipping quantity. We show that the base stock policy is sub-optimal when there is an ordering cost incurred for ordering components. The savings from adopting the batch ordering policy are high and the response time for most customer orders is not affected. When there are shipping costs and shipping time between the two stages, we show that the right selection of the system decision variables can have a large impact on the total cost incurred by the system.

Main focus is to extend the analysis of the ruin related quantities, such as the surplus immediately prior to ruin, the deficit at ruin or the ruin probability, to the delayed renewal risk models. First, the background for the delayed renewal risk model is introduced and two important equations that are used as frameworks are derived. These equations are extended from the ordinary renewal risk model to the delayed renewal risk model. The first equation is obtained by conditioning on the first drop below the initial surplus level, and the second equation by conditioning on the amount and the time of the first claim. Then, we consider the deficit at ruin in particular among many random variables associated with ruin and six main results are derived. We also explore how the Gerber-Shiu expected discounted penalty function can be expressed in closed form when distributional assumptions are given for claim sizes or the time until the first claim. Lastly, we consider a model that has premium rate reduced when the surplus level is above a certain threshold value until it falls below the threshold value. The amount of the reduction in the premium rate can also be viewed as a dividend rate paid out from the original premium rate when the surplus level is above some threshold value. The constant barrier model is considered as a special case where the premium rate is reduced to $0$ when the surplus level reaches a certain threshold value. The dividend amount paid out during the life of the surplus process until ruin, discounted to the beginning of the process, is also considered.

Hybrid Make-To-Stock (MTS)-Make-To-Order (MTO) manufacturing is a well known policy that captures the benefits of both MTS and MTO policies. This manufacturing policy is adopted by many manufacturing firms because it allows for production based on customer specifications while keeping short response times. We study a hybrid MTS-MTO manufacturing system which consists of two processing stages and an intermediate buffer between these two stages. We propose two separate scenarios for ordering and replenishment of components from the first stage which will give more realistic guidance for practitioners. The first scenario is batching customer orders before being released to the first stage. The second scenario is batch replenishment of common components from the first stage. Most existing MTS-MTO models focus on one-for-one ordering and replenishment strategies. We enhance these models by introducing a batch ordering policy to account for economies of scale in ordering when there is an ordering cost associated with each order placed for common components. We use queueing theory to model the system behavior and use the matrix-geometric method to evaluate system performance under the new ordering policy. Afterwards, we develop an optimization model with the objective to minimize the system overall costs. The purpose of our optimization model is to find the optimal intermediate buffer size and the optimal order quantity for the system. In the second scenario, we introduce the batch replenishment policy from stage 1. This policy is suitable when stage 1 and stage 2 are physically distant and there is a shipping cost incurred when components are transferred from stage 1 to stage 2. The decision variables in this model are the intermediate buffer size and the shipping quantity. We show that the base stock policy is sub-optimal when there is an ordering cost incurred for ordering components. The savings from adopting the batch ordering policy are high and the response time for most customer orders is not affected. When there are shipping costs and shipping time between the two stages, we show that the right selection of the system decision variables can have a large impact on the total cost incurred by the system.