I have investigated the evolutionary response of Pseudomonas aeruginosa to salt (NaCl) stress, and the physiological mechanisms responsible for this adaptation. Populations of P. aeruginosa founded from the same ancestral genotype were selected at three different concentrations of NaCl, low, moderate and high for about 660 generations with four independent replicates for each concentration. Adaptation was measured as the fitness of the evolved populations relative to the ancestor assessed in direct, head-to-head competition experiments conducted in the same environment in which they were selected (direct response) as well as in all alternative environments (correlated response). Results suggest that selection in each salt environment led to adaptation to that environment and a modest degree of specialization that evolved because correlated responses to selection were smaller than direct responses. In order to identify the physiological mechanisms contributing to the populations' adaptation in high NaCl concentration, I chose a sample of evolved lines that showed the strongest evidence for specialization to salt and competed them against the common ancestor in KCl and sucrose. Results suggested that increased Na+ /H+ antiporter activity is probably the primary mechanism behind adaptation to high NaCl concentration, however alternative mechanisms cannot be excluded. Tolerance curves, which measure the performance of a genotype across a gradient of salt concentrations, suggested no change in the high salt group’s ability to tolerate extreme concentrations of NaCl. We conclude that high salt evolved population showed improvements to its ionic/osmotic stress resistance strategies mainly to Na+ efflux strategies but with no changes to salt niche.

The genetic requirements for Influenza virus to infect and adapt to new species is largely unknown. To understand the evolutionary steps required by a virus to become virulent, a human virus (A/HK/1/68) (HK), avirulent in mice, was subjected to 20 and 21 serial lung-to-lung passages in mouse. Sequence analysis revealed the emergence of eleven mutations within the NS1 gene of the new virulent strains, many of which occurred in binding sites for transcriptional and translational cellular factors. In the present study we have rescued viruses containing each of the NS1 mouse adapted mutations onto A/PR/8/34 (PR8) backbone. We found 9 of 16 NS1 mutants were adaptive by inducing mortality, body weight loss in BALB/c mice and enhanced virus replication in MDCK cells with properties of host cell interferon transcription inhibition. Sequence comparisons with the highly pathogenic A/Hong Kong/156/1997 (H5N1) and the most severe pandemic A/Brevig Mission/1/1918 (H1N1) NS1 genes showed convergent evolution with some of the mouse adapted viruses for F103L plus M106I and V226I plus R227K mutations respectively. The F103L and M106I mutations in the HK NS1 gene were shown to be adaptive by assessment with respect to replication, early viral protein synthesis, interferon-β antagonism and tropism in the mouse lung. We extended the study and proved increased virulence associated with F103L+M106I mutations in their respective H5N1 NS1 gene on the PR8 and HK backbones, as well as the PR8 NS1 gene and the H9N2 (A/Ck/Bj/1/95) gene in the PR8 and A/WSN/33 backbones respectively. However the V226I and R227K mutations in their respective HK and 1918 NS1 genes slightly enhanced virulence and viral growth at later stages of infection. This study demonstrates that NS1 is a virulence factor; involved in multiple viral processes including interferon antagonism and viral protein synthesis. Furthermore, NS1 mutations acquired during mouse adaptation are proven to be adaptive in human, mouse and avian NS1 genes.

In my dissertation I examine how adaptations of Greek tragedy in South Africa after the fall of apartheid (1994) address the transitional stage of the country and mediate in the formation and apprehension of post-apartheid national identities and the formation of a new communitas. Drawing particularly from Raymond Williams and Jean-Pierre Vernant, I approach tragedy as a paradigmatic model for analyzing the dialectical relationship between cultural text and social context. The examination of this paradigm in the context of post-apartheid South Africa is grounded in postcolonial theory defined as an ongoing project of addressing the politics of identity representation in conjunction with the underlying conditions of cultural and material inequalities in a neo-colonial context. I am focusing on three plays that provide distinct perspectives on the problem of national identity in the post-apartheid era and distinct artistic approaches to the process of adaptation. My examination of each play consists of two, interrelated parts: in the first part, I conduct a structural analysis of the text and an examination of the ways it relates to and reworks the major themes and concepts of the Greek tragedy it adapts. In the second part, I examine the connections between the country’s dominant discourses on national identities and the plays’ representations of these.

In recent decades, rates of type 2 diabetes mellitus (T2DM) and diabetic complications have reached epidemic proportions among Canadian Aboriginal people. Evidence in several populations suggests that abnormal birth weight, particularly low birth weight (LBW) and possibly high birth weight (HBW) may be linked to the development of T2DM. LBW often reflects poor maternal health/ nutritional status which may interfere with normal pancreatic development. HBW is a frequent complication of diabetic pregnancies which are associated with obesity and carbohydrate intolerance in adulthood. Since Saskatchewan Aboriginal newborns historically had higher rates of LBW, and more recently have experienced higher HBW rates, it follows that sub-optimal maternal/ fetal health may be important in the epidemic of T2DM in this population.<p> This thesis describes a case-control study that used Saskatchewan Health databases to determine the relationship between birth weight and T2DM. A sample of 846 adult diabetic Registered Indians (RI) were age and sex matched to three control groups: 1) non-diabetic RI, 2) diabetic general population (GP) subjects, and 3) non-diabetic GP subjects. RI subjects were identified as such by the provincial Health Insurance Registration File.<p> The results of this study show a significant association between HBW (> 4000 grams) and T2DM for RI people [odds ratio (OR) 1.63; 95% confidence interval (CI) 1.20, 2.24]. This association increased in strength from the middle to the latter part of this century and was found to be stronger for RI females than RI males. The comparison of birth weights within the four study groups revealed that diabetic RI (16.2%) were significantly more likely (p<0.05) than controls (10.7%,10.0%, 7.5% respectively) to have HBW. An association between LBW and T2DM (< 2500 grams) was not evident within either RI or GP sample populations.<p> The findings of this study support the hypothesis that HBW and its causes may be risk factors for T2DM among RI people. Programs to prevent gestational diabetes, and to diagnose and optimally manage diabetes during pregnancy could help to reduce rates of diabetes in future generations of Aboriginal peoples.

The cellular networks are evolving to meet the future requirements of data rate,coverage and capacity. The fourth generation mobile communication system, LTEhas been developed to meet these goals. LTE uses multiple antenna features andlarger bandwidths in order to accomplish this task. These features will furtherextend the requirements of data rate, coverage, latency and flexibility. LTE also utilizes the varying quality of the radio channel and the interferencefrom other transmitters by adapting the data rate to the instantaneous channelquality at all the time. This is typically referred to as Link Adaptation. Thelink adaptation fails from time to time due to the varying channel quality as wellas the interference from other transmitters. In order to counteract these failures,retransmission methods are employed. These methods detect the errors on thereceiver side and signals the transmitter for the retransmission of the erroneousdata. The efficiency of link adaptation increases if combined with a properly designedretransmission scheme at the expense of delays due to retransmissions. This master thesis focuses on the study of the retransmission schemes with fasterfeedback, resulting in a reduction in delay. The feedback is generated by makingan early estimate of the decoding outcome and sending it early to the transmitterresulting in faster retransmission. This is important in certain applications wherethe data transmission is intolerant to delays.The thesis work shows by system performance simulations that fast packet retransmission,precisely called Early HARQ Feedback, significantly affects the systemperformance together with the utilization of the link adaptation. The study alsoshows that the link adaptation, in certain scenarios, can be optimized to improvethe system performance. In that respect, it is also possible to increase the numberof retransmissions within the same resource utilization. That optimization is basicallycalled aggressive link adaptation. Consequently, Early HARQ Feedback incombination with aggressive link adaptation provides a large improvement in thedownlink performance of the studied cases.

AIM: The primary purpose of this thesis was to evaluate the pattern of changes to accommodation and phoria when pre-presbyopic individuals perform near work for 20 minutes with +2D lenses. In addition, the thesis also investigates the effect of the accommodative vergence cross-link (AV/A) and age on binocular adaptation to addition lenses. METHODS: Accommodation was measured using the PowerRefractor (Multichannel Systems, Germany) and phoria was measured using the modified Thorington Technique. Twenty four pre-presbyopic and emmetropic individuals (11 adults and 13 children) participated in the study. All participants fixated a near target at a distance of 33 cm for 20 minutes with +2D (lens condition) and without (no lens condition) +2D addition lenses. Binocular and monocular changes in accommodation and near phoria were measured at the outset and at 3, 6, 9, 15 and 20 minute intervals. RESULTS: Effect of +2D lenses on accommodation and phoria: The emmetropic adult participants exhibited lag of accommodation under the no lens condition (binocular: 0.51 ± 0.12D; monocular: 0.64 ± 0.15D) that were eliminated (under monocular viewing) and reversed (exceeded demand by 0.51 ± 0.11 D under binocular viewing condition) with the addition of +2D lenses. The near phoria showed a significant increase towards exophoria by 6 ± 0.56 ∆D upon introduction of +2D lenses. Sustained near viewing with +2 D lenses resulted in significant reduction of the binocular focus alone (not monocular focus) after 3 minutes of binocular viewing (magnitude of reduction: 0.24D; P<0.01). The exophoria also showed a concomitant reduction after 3 minutes of fixation at the near task (Magnitude of reduction: 3.6 ± 0.6 ∆D; P<0.001). The magnitude and rate of vergence adaptation, determined using an exponential function, was found to be 4.6 ± 0.21 ∆D and 2.12 minutes respectively for the emmetropic adult participants. Effect of age on vergence adaptation: A pattern of significant reduction in phoria and binocular focus similar to the adult participants was observed in young children. Analysis of the vergence adaptation curves in the two age groups did not show any significant difference in both the magnitude as well as the rate of phoria adaptation within the age range tested (Magnitude of adaptation - Adults: 4.65 ∆D; Children: 4.51 ∆D; P > 0.05; Time constants -Adults: 2.12 minutes: Children: 1.53 minutes, P > 0.05). Effect of AV/A ratio on vergence adaptation: The stimulus (St-AV/A) and the response AV/A (R-AV/A) ratios were determined and the participants were divided into two groups (low and high AV/A ratio) under both the conditions. The result indicated that, under both testing conditions (stimulus and response AV/A), the individuals with higher AV/A ratios demonstrated greater magnitudes of vergence adaptation than those individuals with lower ratios (Magnitude of adaptation: Low St-AV/A = 4.12 ∆D; Low R-AV/A= 4.25∆D; High St-AV/A = 4.88 ∆D; High R-AV/A = 4.65∆D; P<0.05) CONCLUSIONS: Introduction of near addition lenses initiated an increase in exophoria and convergence driven accommodation. Vergence adaptation occurred after 3 minutes of binocular viewing thus reducing exophoria and convergence driven accommodation. The magnitude and completeness of phoria adaptation were seen to depend on an individuals AV/A ratio with greater magnitude and incomplete adaptation observed in participants with higher AV/A ratios. Age, within the limits of the study did not appear to influence phoria adaptation with near addition lenses.

In my dissertation I examine how adaptations of Greek tragedy in South Africa after the fall of apartheid (1994) address the transitional stage of the country and mediate in the formation and apprehension of post-apartheid national identities and the formation of a new communitas. Drawing particularly from Raymond Williams and Jean-Pierre Vernant, I approach tragedy as a paradigmatic model for analyzing the dialectical relationship between cultural text and social context. The examination of this paradigm in the context of post-apartheid South Africa is grounded in postcolonial theory defined as an ongoing project of addressing the politics of identity representation in conjunction with the underlying conditions of cultural and material inequalities in a neo-colonial context. I am focusing on three plays that provide distinct perspectives on the problem of national identity in the post-apartheid era and distinct artistic approaches to the process of adaptation. My examination of each play consists of two, interrelated parts: in the first part, I conduct a structural analysis of the text and an examination of the ways it relates to and reworks the major themes and concepts of the Greek tragedy it adapts. In the second part, I examine the connections between the country’s dominant discourses on national identities and the plays’ representations of these.

The Sandman is a feature-length screenplay adaptation of E. T. A. Hoffmann’s short story "Der Sandmann." The screenplay re-imagines the story as a contemporary horror film with surrealist underpinnings. The script draws heavily on the gothic tradition. It also draws on the German Romantic tradition out of which Hoffmann writes. The theoretical structure of the screenplay owes a great deal to Sigmund Freud’s ideas about the "uncanny" and concerning the Oedipus complex, the repetition-compulsion, and the death-drive. I do not hold slavishly to these theories so much as use them as points of departure. The story: the young Nathan discovers one day that the Sandman is not a fairytale but a very real creature seemingly bent on his destruction. After abusing Nathan and causing the death of his Father, the Sandman disappears, only to return as Nathan moves away from home to begin his studies at university. Nathan, already haunted by the events of his childhood, spirals further and further into madness. The screenplay is followed by two informal essays concerning the approach taken to the construction of the text. / May 2005

The primary area of study for this thesis is the adaptive reuse of the remaining industrial buildings on Chaudire and Albert Islands in Ottawa, Canada. The recently closed paper mills and the obsolete infrastructure from the bygone lumber industry have the opportunity to be reintegrated with the core area of the nations capital. New uses are introduced to the buildings by material activators which engage spatial and programmatic opportunities of building adaptation. The activators include stair cores, classroom blocks, shoring trusses, glass box windows, and a theatre box. The program that they introduce includes office space, residencies for artists and crafts people, a theatre, galleries, a fabrication shop, and a lap pool. The architectural interventions transform the site into a new commercial and cultural enclave within the capital region, and preserve certain heritage characteristics of the existing buildings architecture.

I have investigated the evolutionary response of Pseudomonas aeruginosa to salt (NaCl) stress, and the physiological mechanisms responsible for this adaptation. Populations of P. aeruginosa founded from the same ancestral genotype were selected at three different concentrations of NaCl, low, moderate and high for about 660 generations with four independent replicates for each concentration. Adaptation was measured as the fitness of the evolved populations relative to the ancestor assessed in direct, head-to-head competition experiments conducted in the same environment in which they were selected (direct response) as well as in all alternative environments (correlated response). Results suggest that selection in each salt environment led to adaptation to that environment and a modest degree of specialization that evolved because correlated responses to selection were smaller than direct responses. In order to identify the physiological mechanisms contributing to the populations' adaptation in high NaCl concentration, I chose a sample of evolved lines that showed the strongest evidence for specialization to salt and competed them against the common ancestor in KCl and sucrose. Results suggested that increased Na+ /H+ antiporter activity is probably the primary mechanism behind adaptation to high NaCl concentration, however alternative mechanisms cannot be excluded. Tolerance curves, which measure the performance of a genotype across a gradient of salt concentrations, suggested no change in the high salt group’s ability to tolerate extreme concentrations of NaCl. We conclude that high salt evolved population showed improvements to its ionic/osmotic stress resistance strategies mainly to Na+ efflux strategies but with no changes to salt niche.