The mixed-grass prairie region of southwestern Manitoba is a hotspot for many endangered grassland birds. This region has been degraded to less than a quarter of its historical amount of mixed-grass prairie. Remaining prairie is primarily used for livestock grazing. The objective of this study was to evaluate the contribution of sustainable land management practices, such as rotational grazing, in the conservation of this region. In 2008 and 2009, I compared the abundances of grassland birds on two grazing regimes, twice-over rotation and season-long, to ungrazed fields. Bird surveys were done during the breeding season and were conducted using 100-m fixed-radius point-count plots. I determined the effects of treatment, landscape and vegetation characteristics on songbird abundances using generalized linear mixed models. Grassland birds selected grazed pastures over ungrazed fields in both years, and species richness of obligate grassland birds was significantly greater (α = 0.10) on season-long than twice-over pastures (β = 0.419, p = 0.032, in 2008 and β = 0.502, p = 0.043 in 2009). Season-long grazing may actually benefit grassland bird communities by creating somewhat temporally stable areas of high use and low use within the pasture. However, nesting success studies and long-term monitoring are necessary to further understand how twice-over rotation grazing systems contribute to the conservation of grassland birds in southwestern Manitoba.

Myocardial infarction (MI) is a leading cause of congestive heart failure (CHF), and its course of cardiac remodeling is of paramount importance in prevention and treatment of cardiac dysfunction. Activation of the sympathetic nervous system (SNS), and the renin angiotensin system (RAS), is critical in cardiac subcellular remodeling post MI. Although blockade has prevented remodeling, little is known regarding the beneficial effects in reversing subcelllular changes in failing hearts. Upon rat coronary artery occlusion - losartan, metoprolol, and prazosin were initiated 12 weeks post MI for 8 weeks, to evaluate their reversal effects at the molecular and cellular levels. As the sarcoplasmic reticulum (SR) primary regulates intracellular Ca2+ in cardiac contraction/relaxation, we hypothesized that abnormalities in its function and regulation contribute to contractile dysfunction. We examined cardiac performance, SR function, SR molecular expression and plasma catecholamine levels 20 weeks post MI. The fibrinous myocardium, cardiac hypertrophy and pulmonary edema all portrayed CHF, in addition to elevated LVEDP and depressed dP/dt. Ejection fraction, fractional shortening, and cardiac output were all significantly reduced, as were IVSs, LVIDd, LVPWs, and LVPWd. SR preparations showed altered phospholamban (PLB) and sarcoplasmic reticulum Ca2+ ATPase (SERCA2a) mRNA, which appropriately matched their protein expression. These modifications correlated to decreased cardiac SR Ca2+-uptake, providing further disruptions in Ca2+ homeostasis. Therefore, these modifications in the mRNA of PLB and SERCA2a are postulated to play a critical role in SR protein remodeling. Supplementary studies addressed remodeling of mRNA myofibrils, which revealed a decreased α-MHC isozyme with an increased β-MHC isozyme, and reduced myofibrillar Ca2+-stimulated ATPase post MI. Finally, circulating plasma catecholamine levels of norepinephrine, epinephrine and dopamine were significantly elevated. Losartan, metoprolol, and prazosin corrected lung edema, myocardial hypertrophy, cardiac contractile dysfunction, and attenuated PLB and SERCA2a proteins, whereas α- and β- MHC mRNA were only attenuated by losartan; and metoprolol only attenuated β-MHC mRNA. SR Ca2+-uptake activities and plasma catecholamines of norepinephrine were partially reversed, yet dopamine was only affected by losartan. Early work previously focused on prevention, but this study is one of the first to attempt reversal of cardiac subcellular remodeling in CHF due to MI.

It is well documented that exposure to intimate partner violence (IPV) negatively affects children’s developmental outcomes (Chan & Yeung, 2009; Evans, Davies & DiLillo, 2008) and may lead to the expression of symptomatology consistent with post-traumatic stress disorder (PTSD) (Graham-Bermann, De Voe, Mattis, Lynch & Thomas, 2006; Kilpatrick & Williams,1998). Currently there is no consensus as to the nature of the influence of mother-child relationships on child outcomes such as post-traumatic stress symptoms in IPV-exposed families. The present study examined the role of maternal influences, such as the quality of mother-child interaction, maternal depression, and maternal violence history on sibling trauma outcomes. Results indicated that increased maternal depressive symptoms, maternal violence history, and negative mother-child interactions did not significantly predict post-traumatic stress symptoms in siblings exposed to IPV. Findings provided support for the notion of maternal compensatory strategies used to protect siblings from the detrimental consequences of IPV exposure.

The thesis is based on using dynamical systems theories and techniques to study the qualitative dynamics of herpes simplex virus type 2 (HSV-2), a sexually-transmitted disease of major public health significance. A deterministic model for the interaction of the virus with the immune system in the body of an infected individual (in vivo) is designed first of all. It is shown, using Lyapunov function and LaSalle's Invariance Principle, that the virus-free equilibrium of the model is globally-asymptotically stable whenever a certain biological threshold, known as the reproduction number, is less than unity. Furthermore, the model has at least one virus-present equilibrium when the threshold quantity exceeds unity. Using persistence theory, it is shown that the virus will always be present in vivo whenever the reproduction threshold exceeds unity. The analyses (theoretical and numerical) of this model show that a future HSV-2 vaccine that enhances cell-mediated immune response will be effective in curtailling HSV-2 burden in vivo. A new single-group model for the spread of HSV-2 in a homogenously-mixed sexually-active population is also designed. The disease-free equilibrium of the model is globally-asymptotically stable when its associated reproduction number is less than unity. The model has a unique endemic equilibrium, which is shown to be globally-stable for a special case, when the reproduction number exceeds unity. The model is extended to incorporate an imperfect vaccine with some therapeutic benefits. Using centre manifold theory, it is shown that the resulting vaccination model undergoes a vaccine-induced backward bifurcation (the epidemiological importance of the phenomenon of backward bifurcation is that the classical requirement of having the reproduction threshold less than unity is, although necessary, no longer sufficient for disease elimination. In such a case, disease elimination depends upon the initial sizes of the sub-populations of the model). Furthermore, it is shown that the use of such an imperfect vaccine could lead to a positive or detrimental population-level impact (depending on the sign of a certain threshold quantity). The model is extended to incorporate the effect of variability in HSV-2 susceptibility due to gender differences. The resulting two-group (sex-structured) model is shown to have essentially the same qualitative dynamics as the single-group model. Furthermore, it is shown that adding periodicity to the corresponding autonomous two-group model does not alter the dynamics of the autonomous two-group model (with respect to the elimination of the disease). The model is used to evaluate the impact of various anti-HSV control strategies. Finally, the two-group model is further extended to address the effect of risk structure (i.e., risk of acquiring or transmitting HSV-2). Unlike the two-group model described above, it is shown that the risk-structured model undergoes backward bifurcation under certain conditions (the backward bifurcation property can be removed if the susceptible population is not stratified according to the risk of acquiring infection). Thus, one of the main findings of this thesis is that risk structure can induce the phenomenon of backward bifurcation in the transmission dynamics of HSV-2 in a population.

Head injuries are very common in daily life and in war field. Head injuries are classified into open and closed. The mechanical mechanisms involved in closed head injuries are very different from those in open head injuries. Closed head injuries are more often re-ported with the use of protective device such as helmets. Helmets were found effective in reducing open head injuries, but less effective for closed head injuries. Finite element modeling is an effective and efficient tool for investigating head injuries. In this thesis, a two-dimensional finite element model was constructed based on a Mag-netic Resonance Image (MRI) scan data from a patient. MATLAB programming was used to extract the information from the MRI scan data. The finite element model was then used to investigate factors affecting closed head injuries. As a new contribution to closed head injury study, the fluid component in the human head, CSF, was studied by a group of comparative simulations. The other three factors, elasticity modulus of the cra-nium, contact area of impact, and impact duration were also investigated. Their effects on reducing the strain values in the brain were measured. Investigation results show that, increasing elasticity modulus of the cranium, contact area of impact and impact duration are very helpful to reduce the strain values in the brain. Helmet is helpful to protect people from closed head injuries because it can change all these three factors by using different shell stiffness and different padding material. The cerebrospinal fluid is effective in protecting the brain from impacts, as a fluid is able to reduce normal strains and filter nearly all shear strains transferred to the brain. It indicates that if a layer of fluid could be added as a layer in a protective helmet, the helmet would be more effective in protecting the brain. Conclusions obtained from the investigations are helpful for preventing closed head injuries and for improving design of protective devices such as helmets.

The thesis focuses on the qualitative analysis of a general class of SEIRS models in periodic and non-periodic environments. The classical SEIRS model, with standard incidence function, is, first of all, extended to incorporate multiple infectious stages. Using Lyapunov function theory and LaSalle's Invariance Principle, the disease-free equilibrium (DFE) of the resulting SEIⁿRS model is shown to be globally-asymptotically stable whenever the associated reproduction number is less than unity. Furthermore, this model has a unique endemic equilibrium point (EEP), which is shown (using a non-linear Lyapunov function of Goh-Volterra type) to be globally-asymptotically stable for a special case. The SEIⁿRS model is further extended to incorporate arbitrary number of latent stages. A notable feature of the resulting SE^mIⁿRS model is that it uses gamma distribution assumptions for the average waiting times in the latent (m) and infectious (n) stages. Like in the case of the SEIⁿRS model, the SE^mIⁿRS model also has a globally-asymptotically stable DFE when its associated reproduction threshold is less than unity, and it has a unique EEP (which is globally-stable for a special case) when the threshold exceeds unity. The SE^mIⁿRS model is further extended to incorporate the effect of periodicity on the disease transmission dynamics. The resulting non-autonomous SE^mIⁿRS model is shown to have a globally-stable disease-free solution when the associated reproduction ratio is less than unity. Furthermore, the non-autonomous model has at least one positive (non-trivial) periodic solution when the reproduction ratio exceeds unity. It is shown (using persistence theory) that, for the non-autonomous model, the disease will always persist in the population whenever the reproduction ratio is greater than unity. One of the main mathematical contributions of this thesis is that it shows that adding multiple latent and infectious stages, gamma distribution assumptions (for the average waiting times in these stages) and periodicity to the classical SEIRS model (with standard incidence) does not alter the main qualitative dynamics (pertaining to the persistence or elimination of the disease from the population) of the SEIRS model.

A better understanding of people’s attitudes to housing is fundamental to attracting new residents and retaining those who already live in or close to the central city. As such, this study operating in a Canadian context adopts Hägerstrand’s model for the process of innovation diffusion. The study draws on the findings of an online survey and interviews with city planners in both Edmonton and Winnipeg to explore the demand and supply dimensions of city-center living and attitudes towards different types of housing and neighbourhood design. The study shows that the central area in Winnipeg and Edmonton are at different stages regarding housing. Prospective home owners who are interested in housing in the central area share a number of environmental attitudes. These attitudes were related to the care for recycling, the importance for eating organic food, the use of public transportation, volunteering in non-profit organization to help the community and the interest in attending cultural activities. Based on the results of the study, it can be expected that housing types such as apartments, townhouses and even loft housing can be more common in the future and especially in Winnipeg since apartments and townhouses are already common in Edmonton.

Many elderly people of Aboriginal origin find themselves displaced as they move from rural reserves into unfamiliar urban settings. The majority are forced to relocate to cities for medical purposes and fall between the cracks of an already fragile support system. Responsibility for their needs, particularly in relation to housing, is not clearly assigned to band organizations or governments. They seek shelter wherever they can. Some move in with family members or friends. Others secure units in non-profits, while several reside in single room occupancy hotels or rooming houses. In Winnipeg, and throughout Canada, specific numbers and individual circumstances of this demographic remain relatively unknown. Preliminary research indicates many are living in unhealthy and unsafe environments. This study begins to document the situations and conditions in which elderly people of Aboriginal origin are currently living. This task is achieved through a review of pertinent literature and through empirical work in the form of focus groups and semi-structured interviews. Participants include elderly Aboriginals and officials from Winnipeg and across Canada. The thesis aims to construct a body of evidence which highlights the housing needs of elderly Aboriginals. It also aims to assist the Aboriginal Senior Resource Centre (ASRC) in supporting elderly people of Aboriginal origin in Winnipeg and concludes with recommendations for policy makers, arguing for immediate implementation as well as further study.

Schools have always played an important role in modern society. They are a reflection of local values and changing educational and societal trends. The 21st century brings with it a multitude of challenges as we design schools and communities that embrace and engage learners in an era of global communication and unfettered knowledge exchange. This project explores the concept of a school-centred neighbourhood in response to these changes. Through a case study review of Grande Prairie’s Community Knowledge Campus, the study looks at the social influences of a multi-use school facility through the use of indicators of social capital, lifelong learning and learning-based community development. Interviews with school and municipal planners as well as facility users are used to explore the intended purpose of the development and to measure the effectiveness of this concept. The study concludes that multi-use school facilities have a measurable impact on the promotion of these social elements and thus contribute to the creation of a school-centred neighbourhood. Six recommendations are presented at the end of this study for use by school and municipal planners. These include: i) central locations and community linkages, ii) efficiencies and flexibility through multi-use school facilities, iii) the promotion of joint-use agreements, iv) coordinated school board capital planning and municipal land use planning, v) establishing a common planning language between schools and municipalities and vi) community planning and neighbourhood design through CKCs.

This practicum focuses on the issues of the overlapping boundaries between Student housing and downtown redevelopment. Can graduate students find a place in the downtown to meet their need for off-campus housing, and simultaneously help build a healthy, vibrant, downtown community; ensuring the housing facility represents a quality space for both graduate students and the local community? The following is an investigation of related issues including: Richard Florida’s notion of the Creative Class, multi-purpose development, the university as an urban catalyst, and adaptive reuse. The combination of graduate housing and the city’s downtown redevelopment will create new design typology that benefits both graduate students and downtown community. The practicum project consists of a live/work space for Winnipeg in the Waterfront area by adaptively reusing the James Ave Pumping Station building. The renovated building includes a bookstore, a coffee shop, a daycare, and an urban grocery store. However, the design focuses on the informal learning space and the quality of graduate students’ living experience through aspects such as accommodation, study space, meeting and casual spaces.