The Yellow Quill Mixed Grass Prairie Preserve is a remnant of an endangered community that is located in southwestern Manitoba and owned by The Nature Conservancy of Canada. In 2005 and 2006, this study was conducted to investigate the effect that the currently-practiced twice-over rotational cattle grazing regime is having on the carabid beetles and spiders. This study primarily compared grazed and ungrazed treatments on three paddocks. A secondary experiment investigated whether the spring graze, fall graze, or the combination of the two had the greatest impact on the carabids and spiders. Three periods were examined in three periods each season: before grazing had begun, after the spring graze, and after the fall graze. A total of 81 species of carabids and 156 species of spiders were recorded, including potentially new provincial records (two carabid species and 20 spider species). Seventy two species of plants were recorded in the study.

Net ecosystem carbon dioxide exchange (NEE) was measured using the eddy covariance (EC) technique at a wetland tundra-sedge fen near Churchill, Manitoba, Canada during two consecutive growing seasons (2007 and 2008). Mean daily NEE at the fen (DOY 157-254) was -3.5 (± 0.26 S.E.) g CO2 m-2 d-1 in 2007 and -4.6 (± 0.36) g CO2 m-2 d-1 in 2008. The fen was a net carbon dioxide (CO2) sink during both the 2007 and 2008 growing seasons of -343 (± 79) and -450 (± 87) g CO2 m-2, respectively. Mean air temperature during the summer (June 1-August 31) was about 1°C greater than the historical average (1971-2000) in 2007 and about 2°C greater in 2008. Growing season precipitation was 107.5 mm below normal in 2007 and 359.5 mm above normal in 2008. These data suggest that if future climate change brings warmer temperatures and near-to-above average precipitation maintaining the water table near the surface, similar subarctic ecosystems will experience increased gross ecosystem productivity enhancing CO2 sequestration during the growing season.

In Manitoba, potato fields have been found to be infested with Verticillium dahliae, which can produce Vertcillium wilt disease severity of up to 90% and reduce yield. Potato producers have then an increased interest on use of green manures and organic amendments to control Verticillium wilt. The objectives of this research were to evaluate selected green manure and organic amendments for their ability to reduce propagule density of V. dahliae in soil, incidence and severity of Verticillium wilt, and to enhance potato yield in Manitoba. In addition, a second study was conducted for the purpose of studying the potential of mustard green manure and seed meal to inhibit the germination of microsclerotia. Findings suggest that composted-cattle-manure and oriental mustard seed-meal amendments have promise as an alternative strategy for the control of V. dahliae. However, only composted beef cattle manure reduced disease, increased potato yield and improved nutrient availability (P) in soil

The purpose of this thesis was to compare ethinylestradiol (EE2) and nitrogen removal in a conventional membrane bioreactor (C-MBR) and a simultaneous nitrification-denitrification membrane bioreactor (SND-MBR). Two MBRs were operated in parallel for 450 days; various MBR operating parameters, total nitrogen removal, and estrogenic activity removal (EA) were measured. The SND-MBR was able to remove 59% of influent TN with an additional 21% removed via sludge wasting; the C-MBR had a TN removal efficiency of only 31%. The C-MBR and SND-MBR removed 57% and 58% of influent EA, respectively. Biodegradation was the dominant removal mechanism for both reactors with KBIO coefficients of 1.5 ± 0.6 and 1.6 ± 0.4 days-1 for the C-MBR and the SND-MBR, respectively. Adsorption removed approximately 1% of influent EA in each reactor. This indicates that SND was able remove greater amounts of TN with no observable impact on EA reduction and membrane operations.

The true prevalence of hepatitis B virus (HBV) infections in Northern Canada is underreported owing to the lack of occult-HBV studies. Clinical outcomes of HBV infections are variable; such that active disease is rare in Canadian and Greenlandic Inuit, yet hepatocellular carcinoma (HCC) is prevalent among genotype F (HBV/F) infected Alaskan Natives. The purpose of this study is to determine the true extent of occult infections in Northern Canada and the rate, nature and regional susceptibility of HBV genomic mutations among circumpolar indigenous populations. The occurrence of occult infections in 700 archived serum samples from Northern Canada was determined by viral DNA amplification. In addition, HBV mutational analysis was performed on 15 indigenous peoples infected by one of 3 HBV genotypes (B6, D and F), which are associated with varying outcomes, including inactive liver disease and HCC. Phylogenetic analyses and genetic variation was investigated with full-length HBV genomes. The results show 3.8% of 700 study subjects to be occult-HBV positive, with half of them infected with HBV/A. This study also reveals HBV/F strains contain deletions and substitutions associated with adverse outcomes, while HBV/D and B6 sequences lacked these mutations and contained mutational patterns associated with a benign outcome. The genetic diversity within the dominant and subclonal population levels are higher for HBV/B6 strains compared to HBV/D and HBV/F strains. The increased genetic variability found in virus associated with inactive disease may be indicative of an escape mechanism used by HBV to evade the host immune response or simply co-evolution between the virus and its host. These observations may demonstrate the association between differing clinical outcomes and infecting genotype in circumpolar indigenous populations.

HIV-1 integrase (IN) enzyme employs several viral and cellular proteins for nuclear translocation and crucial integration of viral cDNA. Successful identification of new viral/cellular interactions may shed light for better understanding of HIV-1 replication. 293T cells were transiently transfected with pYEF-1-TAP-IN and cell lysate were subjected to Tandem Affinity Purification system to pull down putative IN-interacting cellular partners. A number of distinct bands from the Coomassie-stained gel were excised followed by in-gel digestion and mass spectrometry. Putative cellular partners of HIV-1 IN were heat shock protein 60 (HSP60), β-tubulin, γ-actin, ATP synthase alpha subunit and histone H1.2 were identified by mass spectrometry. Additionally, SF3A3 (splicing factor 3A3), another previously reported factor, was successfully co-immunoprecipitated with IN. The C-terminal portion of IN was found to be the region of interaction with SF3A3. Overall, this study has provided better understanding of IN dynamics enriching existing knowledge of HIV-1 IN biology.

The following research thesis examined services offered by the Ozosunon program which is an Aboriginal Foster Care program. Its focus is to have Aboriginal families care for Aboriginal children within the community. The Ozosunon Neighbourhood Care Program Evaluation examined two primary questions: 1. Does the Ozosunon program provide services that are culturally appropriate? If the services are determined to be culturally appropriate, a second question was posed in an attempt to address the benefits of the services: 2. Does the Ozosunon program provide culturally appropriate services that support the child’s needs? The research was a mixed qualitative and quantitative study. The methods used were semi-structured interviews and questionnaires aimed at collecting relevant information regarding the program and the services offered. The results of the research showed that there are many shared positive views from participants regarding the program and its services. The responses showed that the program is offering cultural services but that perspectives regarding what that means were varied. After having completed the research it appears there is a need for further study on the services offered by the program, particularly how they are understood by staff, foster parents and families.

First in 1997, and later re-emerging in 2003, highly pathogenic avian influenza A virus, subtype H5N1, has spread from wild bird reservoirs to domestic bird flocks. As a result, cross-transmission has been confirmed in people living or working in close contact with infected birds. H5N1 virus infection is associated with a high mortality rate (>60%) in humans and the rapid evolution of the virus suggests that it could potentially develop into a new, and possibly severe, pandemic influenza virus. To-date, conventional inactivated and live-attenuated vaccine strategies offers the best protection against influenza virus infection; however, poor immunogenicity and weaker efficacy have been observed against H5N1 viruses. It was hypothesized that experimental adenovirus-based vaccines based on human adenovirus serotype 5 (AdHu5) or porcine adenovirus serotype 3 (PAV3) can offer protection against a broad range of avian influenza, subtype H5N1, viruses. Ad vaccine vectors are highly immunogenic and have demonstrated protective efficacy against several disease models. However, natural immunity against AdHu5 can interfere with vector efficacy. The nonhuman PAV3 was not neutralized by pooled human serum from 10,000-60,000 individuals and offers a promising alternative to AdHu5-based vectors. Systematic antigen screening using DNA vaccines identified the hemagglutinin (HA) glycoprotein as the most immunogenic H5N1 antigen. HA was then inserted directly into PAV3 or AdHu5. Comparable immune responses were observed between both vectors but, interestingly, the PAV3-based vaccine generated stronger T-cell responses and better rapid protection 8 days following immunization. Additionally, better long-term protection 1 year following vaccination was observed with the PAV3-HA vaccine. The co-administration of multiple H5N1 antigens was also screened to improve protection against divergent H5N1 challenge. Combinations of DNA vaccines expressing (HA+NA) and (HA+NP) offered the best promise for enhancing protection against homologous and heterologous H5N1 challenges, respectively. However, addition of three or more antigens reduced overall protection possibly by antigen dilution, competition, or interference. Co-administration of PAV3 or AdHu5 vectors expressing both the HA and NP antigens reduced protection against homologous and heterologous H5N1 virus challenges. For all combination vaccines, T-cell responses were strong against HA but significantly decreased against additional antigens in each combination vaccine. Overall, the experimental porcine-based Ad-based vaccine offered better protection than the H5N1 conventional vaccine against a broad range of different H5N1 viruses. Understanding of the relationship between immune parameters and protection will be critical in future improvement of adenovirus-based and other vaccines against avian influenza H5N1.

Tracheal respiratory sounds analysis has been investigated as a non-invasive method to estimate respiratory flow and upper airway obstruction. However, the flow-sound relationship is highly variable among subjects which makes it challenging to estimate flow in general applications. Therefore, a robust model for acoustical flow estimation in a large group of individuals did not exist before. On the other hand, a major application of acoustical flow estimation is to detect flow limitations in patients with obstructive sleep apnea (OSA) during sleep. However, previously the flow--sound relationship was only investigated during wakefulness among healthy individuals. Therefore, it was necessary to examine the flow-sound relationship during sleep in OSA patients. This thesis takes the above challenges and offers innovative solutions. First, a modified linear flow-sound model was proposed to estimate respiratory flow from tracheal sounds. To remove the individual based calibration process, the statistical correlation between the model parameters and anthropometric features of 93 healthy volunteers was investigated. The results show that gender, height and smoking are the most significant factors that affect the model parameters. Hence, a general acoustical flow estimation model was proposed for people with similar height and gender. Second, flow-sound relationship during sleep and wakefulness was studied among 13 OSA patients. The results show that during sleep and wakefulness, flow-sound relationship follows a power law, but with different parameters. Therefore, for acoustical flow estimation during sleep, the model parameters should be extracted from sleep data to have small errors. The results confirm reliability of the acoustical flow estimation for investigating flow variations during both sleep and wakefulness. Finally, a new method for sleep apnea detection and monitoring was developed, which only requires recording the tracheal sounds and the blood's oxygen saturation level (SaO2) data. It automatically classifies the sound segments into breath, snore and noise. A weighted average of features extracted from sound segments and SaO2 signal was used to detect apnea and hypopnea events. The performance of the proposed approach was evaluated on the data of 66 patients. The results show high correlation (0.96,p < 0.0001) between the outcomes of our system and those of the polysomnography. Also, sensitivity and specificity of the proposed method in differentiating simple snorers from OSA patients were found to be more than 91%. These results are superior or comparable with the existing commercialized sleep apnea portable monitors.

Although the demand for high scale production of mammalian orthoreoviruses (T3D in particular) is mounting to advance the research studies and clinical trials associated with their oncolytic capacity, very few reported studies have tried to understand the factors that affect the its production and subsequently optimize them to maximize the virus yield in cell culture systems. For this study, we manipulated several growth parameters (multiplicity of infection, cell density, cell feeding, media pH, and flask size) sequentially to select optimal conditions. Manipulation of cell density, whether cells were fed or not, and flask size all led to moderate changes in progeny virus titer. Altered media pH led to dramatic (more than 100 fold) virus replication changes. We conclude that cell physiological status has a key impact on infection progression and virus production. Optimal parameters consisted of infection at MOI of 0.1, cell density at infection of 95%, media re-feeding, media pH 7.0-8.5, and the smaller the flask size the better.