VictorJuiz/thesis huggingface dataset:
Functional Characterization of Members of a Clade of F-box Proteins in Arabidopsis thaliana
Keywords: F-box Proteins
Arabidopsis thaliana
brevipedicellus
yeast two hybrid

In Arabidopsis, the F-box gene family encodes a large number of proteins postulated to act as substrate selectors for proteasome-mediated protein degradation. Recent reports document the importance of F-box proteins in developmental and metabolic signaling. Our microarray analyses of inflorescences of the brevipedicellus(bp) mutant indicate several F-box proteins are upregulated, suggesting that BP represses these genes in wild type plants to condition normal inflorescence development. We undertook analyses to examine the function of these proteins and their contribution to the pleiotropic phenotypes of bp. Yeast-2-hybrid screens revealed that the F-box protein At1g80440 binds to phenylalanine ammonia lyase-1(PAL1), the gateway enzyme of phenylpropanoid metabolism. Transgenic lines driven by the 35S cauliflower mosaic virus were attained but could not be propagated, suggesting a fatal phenotype. BP driven F-box expression results in phyllotaxy defects, manifest as alterations in the emergence of inflorescence and floral meristems in the axils of some cauline leaves.
Progressive Validity Metamodel Trust Region Optimization
Keywords: Multidisciplinary Optimization
Metamodels
Response Surfaces
Surrogate Models
Trust Region Optimization
Progressive Validity
Leave-k-out Cross-Validation
Concurrent Subspace Optimization

The goal of this work was to develop metamodels of the MDO framework piMDO and provide new research in metamodeling strategies. The theory of existing metamodels is presented and implementation details are given. A new trust region scheme --- metamodel trust region optimization (MTRO) --- was developed. This method uses a progressive level of minimum validity in order to reduce the number of sample points required for the optimization process. Higher levels of validity require denser point distributions, but the reducing size of the region during the optimization process mitigates an increase the number of points required. New metamodeling strategies include: inherited optimal latin hypercube sampling, hybrid latin hypercube sampling, and kriging with BFGS. MTRO performs better than traditional trust region methods for single discipline problems and is competitive against other MDO architectures when used with a CSSO algorithm. Advanced metamodeling methods proved to be inefficient in trust region methods.
An Empirical Approach to Understanding the Relationship Between Recombination and Fitness
Keywords: fitness
recombination
coincidence
Drosophila melanogaster
evolution of sex

The persistence of sex is a recurrent conundrum in evolutionary biology because sex is costly. These costs may be accounted for by looking at the outcome of sex, namely that sex causes genetic mixing. Recombination is one of the processes by which sex causes genetic mixing; determining when recombination is advantageous may alleviate some of the costs of sex. The advantages of recombination are in the effects of recombination and the influences thereupon. The first experiment focuses on the effects of recombination on the mean fitness and variance in fitness. A second experiment examines the influences on recombination by addressing whether recombination is a general response to poor condition. Specifically, the impact on recombination rate of genotypes with variable fitness is investigated. Differing fitness effects are not correlated to recombination rates. Conversely, coincidence, a recombination related trait, is positively correlated with fitness.
Labeling and Detection of Marrow Derived Mesenchymal Stromal Cells using Magnetic Resonance Imaging
Keywords: MRI
MPIO
stem cells
superparamagnetic iron oxide
stroke

Stem cell therapies hold great promise for diseases such as stroke, where few effective treatment options exist. Clinical translation of experimental stem cell therapies requires the ability to monitor delivery and behaviour of cells non-invasively in-vivo with clinical imaging modalities such as MRI. This thesis presents the translation of established methods for labelling and imaging stem cells with specialized MRI systems to a more clinically relevant setting. A methodology for harvesting and labelling a cell population containing stem cells with iron oxide for detection with a clinical MRI system is presented and single cell detection is demonstrated in-vitro. The feasibility of detecting iron oxide labelled stem cells intravenously delivered in a rat model of stroke is tested. Results demonstrate that while MRI is highly sensitive to the presence and distribution of iron oxide containing cells in-vivo the true origin of these cells remains ambiguous with the current methodology.
The Processes of Care after Colorectal Cancer Surgery in Ontario
Keywords: colorectal cancer
surveillance
relapse

Colorectal cancer (CRC) is common in Ontario. This study described the processes of care following CRC resection, and identified CRC relapse from administrative data. Methods: CRC patients aged 18-80 from 1996-2001 with a colorectal resection were identified from the Ontario Cancer Registry. Linked discharge abstracts and physician billings were examined for physician visits, body imaging and endoscopy over the 5 year follow-up period. Administrative codes suggesting disease relapse were compared with patient charts. Results: Overall, 12,804 patients were identified and 8,804 had no evidence of relapse. Most (96.2%) patients had general practitioner follow-up, while 49.3% had medical oncology and 80.4% had general surgery follow-up. Greater than 90% of patients received endoscopy, while only 68.7% of patients received body imaging. Detecting disease relapse was 87.5% sensitive and 93.0% specific. Conclusions: There is potential for improving post-resectional follow-up in CRC patients. It is possible to detect relapse through administrative databases.
A Climate Change Impact Assessment on the Spread of Furunculosis in the Ouje-Bougoumou Region
Keywords: climate change
Aboriginal health
furunculosis

A climate change impact assessment was conducted to examine the spread of furunculosis found in the fish species of Ouje-Bougoumou; and subsequently to examine the resulting impacts on the health of the community. A past assessment was performed to assess whether there was a temporal relationship between increased temperatures and past incidences of furunculosis using observed climate data and traditional ecological knowledge (TEK) data. To project future impacts of climate change, climate models, lake models and TEK were used. Findings show that the rise in air mean temperature coincides with the timeline of past incidences of furunculosis. It is predicted that the lake temperatures will remain suitable for the presence of A. salmonicida; thus, it is likely that the disease will persist throughout the twenty-first century. To conclude, climate change is not eliminated as a plausible factor to the onset of furunculosis.
The Role of Carbonic Anhydrase in the Modulation of Central Respiratory-related pH/CO2 Chemoreceptor-stimulated Breathing in the Leopard Frog (Rana pipiens) Following Chronic Hypoxia and Chronic Hypercapnia
Keywords: Acetazolamide
Amphibian Respiration
Carbonic Anhydrase
Central pH/CO2 Chemoreceptors
Chronic Hypercapnia
Chronic Hypoxia
Fictive Breathing
In Vitro Brainstem-Spinal Cord Preparation
Leopard Frogs

The aim of this thesis was to elucidate the role of carbonic anhydrase (CA) in the modulation of central pH/CO2-sensitive fictive breathing (measured using in vitro brainstem-spinal cord preparations) in leopard frogs (Rana pipiens) following exposure to chronic hypercapnia (CHC) and chronic hypoxia (CH). CHC caused an augmentation in fictive breathing compared to the controls (normoxic normocapnic). Addition of acetazolamide (ACTZ), a cell-permeant CA inhibitor, to the superfusate reduced fictive breathing in the controls and abolished the CHC-induced augmentation of fictive breathing. ACTZ had no effect on preparations taken from frogs exposed to CH. Addition of bovine CA to the superfusate did not alter fictive breathing in any group, suggesting that the effects of ACTZ were due to inhibition of intracellular CA. Taken together, these results indicate that CA is involved in central pH/CO2 chemoreception and the CHC-induced increase in fictive breathing in the leopard frog.
Building High Performing Globally Dispersed Teams: Challenging Inequality to Establish Trust
Keywords: global workplace
Organization Development
team development
team facilitation
equity
inequality
diversity
diversity management
Postcolonial Theory
autoethnography
storytelling
personal stories
globally dispersed teams
high performing teams
trust
conflict
social justice
virtual
power
difference
identity

This thesis explores barriers to the establishment of trust needed for high performing teams due to inequality in the context of a global economy. Postcolonial Theory is introduced to illustrate how inequality is a key aspect of diversity in the current context of the global workplace. Different philosophies underlying the values and norms in organizations are examined to make sense of contemporary approaches to diversity management in terms of how power, difference, and identity are addressed. This provides an understanding of the context of current team development praxis in working with diversity. Using autoethnography, the author tells personal stories of working in diverse teams to convey the complex ways in which power, difference, and identity coalesce in real-life experience. Some theoretical foundations are developed for facilitating the building of team trust in contexts with different philosophical approaches to diversity. Addressing social justice in Organization Development work is considered.
Widely-linear MMSE Receivers for Linear Dispersion Space-time Block-codes
Keywords: multiple-input multiple-output communication systems
space-time coding techniques
linear dispersion (LD) codes

Space-time coding techniques are widely used in multiple-input multiple-output communication systems to mitigate the effect of multipath fading in wireless channels. An important subset of space-time codes are linear dispersion (LD) codes, which are used for quasi-static Rayleigh flat fading channels when the channel state information (CSI) is only available at the receiver side. In this thesis, we propose a new receiver structure for LD codes. We suggest to use widely-linear minimum-mean-squared-error (WL-MMSE) estimates of the transmitted symbols in lieu of the sufficient statistics for maximum likelihood (ML) detection of these symbols. This structure offers both optimal and suboptimal operation modes. The structures of the proposed receivers in both modes are derived for general LD codes. As special cases, we study two important subsets of LD codes, namely orthogonal and quasi-orthogonal codes, and examine the performance of the proposed receivers for these codes.
The Role of Human Leukocyte Antigen-G in Heart Transplantation
Keywords: Heart Transplantation
HLA-G

Primarily expressed by trophoblast cells, human leukocyte antigen-G (HLA-G) plays an essential role in maintaining maternal-fetal immune tolerance. Having previously been detected following heart transplantation, we sought to establish the value of HLA-G in identifying freedom from moderate or severe rejection post-heart transplant, and the capability of its expression in vitro. After assessing myocardial HLA-G expression through immunohistochemistry, we demonstrated that it was significantly more prevalent in non-rejecting than rejecting heart transplant recipients. Utilizing vascular endothelial and smooth muscle cell culture models, we also determined that while HLA-G expression remains tightly regulated, its expression in vitro can be induced following progesterone treatment in a dose-dependent manner. Hence, HLA-G may reliably identify patients with a low immunological risk of developing subsequent clinically significant rejection post-heart transplant. Furthermore, HLA-G expression can be induced in cultured endothelial and smooth muscle cells, which might represent a strategy to protect against allograft rejection and vasculopathy.
Structural and Functional Insights on Regulation by Phenolic Compounds
Keywords: aromatic amino acid synthesis
metabolic regulation

The shikimate pathway is a primary metabolic pathway involved in the synthesis of aromatic compounds in plants, fungi, apicomplexan parasites and microbes. The absence of this pathway in animals makes it ideal for the synthesis of antimicrobial compounds and herbicides. Additionally, its branching into indole hormone synthesis and phenylpropanoid secondary metabolism makes this pathway attractive for metabolic engineering. Here, the focus is on the first step of the shikimate pathway catalyzed by DAHP synthase. This step consists of the condensation of phosphoenol pyruvate and erythrose-4-phosphate to make DAHP, which undergoes another six catalytic steps to synthesize chorismate, the precursor of the aromatic amino acids. Arabidopsis thaliana contains three DAHP synthase isozymes, which are known to indirectly regulate downstream pathways in response to wounding and pathogen stress. The model presented here proposes that DAHP synthase isozymes are regulated by the end products tyrosine, tryptophan and phenylalanine.
The Inhibitory Effect of Kell Blood Group Antibodies on Erythroid Progenitor Cell Growth
Keywords: hemolytic disease of the fetus and newborn
Kell

The clinical manifestations of hemolytic disease of the fetus and newborn mediated by anti-K, an antibody of the Kell blood group system, are distinguishable from the classical form of the disease. Affected fetuses have low numbers of circulating reticulocytes and antibody titers and bilirubin levels are not reliable predictors of anemia. These observations suggest that antibodies to Kell glycoprotein lead to anemia through suppression of erythropoiesis. This study established a liquid erythroid progenitor cell culture model in which to perform analyses on the mechanism of the suppressive growth effect of anti-Kell glycoprotein. Using this culture model, this study demonstrated the requirement for co-ligation of Kell glycoprotein by a bivalent antibody for growth suppression. The absence of markers of apoptosis in cell cultures treated with anti-Kell glycoprotein suggests that the mechanism of growth suppression is distinct from programmed cell death and necrosis. Furthermore, this growth suppression cannot be rescued by erythropoietin.
Analyses of Host Specificity, Immune Interactions and New Virulence Candidates of Pseudomonas syringae
Keywords: host specificity
Pseudomonas syringae
immune interactions

We studied the host specificity, interactions with plant immune systems, and virulence factors of the phytopathogenic Type III secretion system-carrying bacterium Pseudomonas syringae. In studying host specificity, we ran growth and pod assays using seventeen pathovars of P. syringae on kidney bean hosts. We tracked bacterial growth numbers over six days and compared pathovar growth patterns. To study immune interactions with host plants, we performed effector-triggered immunity induction and suppression assays with individual effectors in Arabidopsis thaliana to determine whether effector evolutionary age was related to resultant plant immune responses. No correlations were observed. To generate candidate virulence effectors, we sequenced mRNA from seven P. syringae pathovars grown in inducing media and pulled out hits to virulence-related genes.
Adaptive Processing in High Frequency Surface Wave Radar
Keywords: Adaptive Processing
Radar
HFSWR
Low Complexity
Multistage

High-Frequency Surface Wave Radar (HFSWR) is a radar technology that offers numerous advantages for surveillance of coastal waters beyond the exclusive economic zone. However, target detection and tracking is primarily limited by ionospheric interference. Ionospheric clutter is characterized by a high degree of nonhomogeneity and nonstationarity, which makes its suppression difficult using conventional processing techniques. Space-time adaptive processing techniques have enjoyed great success in airborne radar, but have not yet been investigated in the context of HFSWR. This thesis is primarily concerned with the evaluation of existing STAP techniques in the HFSWR scenario and the development of a new multistage adaptive processing approach, dubbed the Fast Fully Adaptive (FFA) scheme, which was developed with the particular constraints of the HFSWR interference environment in mind. Three different spatio-temporal partitioning schemes are introduced and a thorough investigation of the performance of the FFA is conducted.
Neuropsychological Contributions to Symptomatology in Eating Disordered Patients
Keywords: eating disorders
neuropsychology
set-shifting
decision-making

The present study examined the claim that neuropsychological deficits in set-shifting and emotional decision making are present in eating disordered patients, and to what extent these deficits relate to specific aspects of disordered eating. Sixteen eating disordered patients and 38 controls were given a battery of neuropsychological measures, as well as questionnaires measuring disordered eating. Compared to controls, patients demonstrated poorer performance on tasks of set-shifting, but not decision making, psychomotor speed, working memory, or IQ. Across groups, poor set-shifting was correlated with food-, shape-, and weight concerns, and restricting, whereas poor decision making was correlated to restricting. The study demonstrates that set-shifting deficits are present in eating disordered patients, and that specific relations exist between cognitive performance in different domains and disordered eating.
Utility of the Cytochrome Oxidase I gene (COI) for Species Identification and Phylogeographic Analysis in Black Flies (Diptera: Simuliidae)
Keywords: DNA Barcoding
Simuliidae
Phylogeography
Population Genetics

A short sequence of ca. 658-bp of the mitochondrial gene COI was used to investigate its utility as a DNA barcode in the medically important Simuliidae or black flies. Sixty-five species and species complexes were tested. Results indicate that the barcoding gene discriminated among morphologically distinct species with nearly 100% of efficacy and proved useful for revealing cryptic diversity. The DNA barcoding gene was also tested for revealing phylogeographic patterns in the western cordilleran Prosimulium travisi and the Prosimulium neomacropyga species-group. Phylogeographic analyses on these species revealed areas that acted as glacial refugia, postglacial history, cryptic speciation episodes and timing of the events that lead to their present-day distribution. The results obtained concur with other phylogeographic studies on similarly-distributed cordilleran organisms. In conclusion, the barcoding gene not only resulted useful for species discrimination in black flies but also for studies at the population level, providing value-added to this molecular marker.
The Role of South Asian Traditional Healers in Counselling
Keywords: Counselling Psychology
South Asian
Traditional Healers
Traditional Healing

The current study’s aim was to explore and document the role of South Asian traditional healers residing in Toronto as it has been observed that South Asians tend to approach these traditional healers for assistance with their physical, psychological and spiritual distresses. These healers were interviewed about their background, training, the South Asian traditional healing processes and their thoughts on collaboration with Western Mental Health practitioners. The data was analyzed using Grounded Theory. The results revealed that these traditional healers closely followed the South Asian traditional healing theories and cultural norms in their practices. The healing processes reflected the ideas of holism, planetary effects and religious healing. The traditional healers also expressed eagerness to associate with the Western Mental Health care services to benefit their clients. The findings suggest that South Asian traditional healers play a major role in the lives of South Asians.
Early Endothelial Progenitor Cells and Cardiac Transplant Vasculopathy
Keywords: Endothelial Progenitor Cell
adhesion

Cardiac allograft vasculopathy (CAV) limits survival after heart transplantation. CAV is caused by damage to the allograft endothelium, resulting in occlusive intimal lesions. Administration of ex vivo cultured early endothelial progenitor cells (eEPCs) enhances endothelial repair and inhibits intimal hyperplasia. However, engraftment rates of eEPCs remain low. We examined changes in eEPC adhesion molecule expression during ex vivo cultivation, and how these changes affect their ability to adhere. Compared to their parent cell population (freshly isolated peripheral blood mononuclear cells, PBMCs), eEPCs had decreased expression of integrins necessary to form firm adhesions with endothelial cells. Despite this eEPCs showed an enhanced ability to adhere under static conditions compared to PBMCs. However, under conditions of physiological flow, eEPC rolling adhesion was reduced compared to PBMCs. We hypothesize that low eEPC retention rates observed in vivo may be due to impaired eEPC rolling resulting from ex vivo culture.
Synthesizing Agents and Relationships for Land Use/Transportation Modelling
Keywords: Transportation
Urban Planning
Civil Engineering

Agent-based microsimulation models of socioeconomic processes require an initial synthetic population derived from census data. This thesis builds upon the Iterative Proportional Fitting (IPF) synthesis procedure, which has well-understood statistical properties and close links with log-linear models. Typical applications of IPF are limited in the number of attributes that can be synthesized per agent. A new method is introduced, implementing IPF with a sparse list-based data structure that allows many more attributes per agent. Additionally, a new approach is used to synthesize the relationships between agents, allowing the formation of household and family agents in addition to individual person agents. Using these methods, a complete population of persons, families, households and dwellings was synthesized for the Greater Toronto Area and Hamilton.
Attitude Sensing, Actuation, and Control of the BRITE and CanX-4&5 Satellites
Keywords: Attitude
Control
Satellite
Sensing

An attitude control system for the BRITE and CanX-4&5 nanosatellites is developed. BRITE and CanX-4&5 are research satellites based on the Space Flight Laboratory’s Generic Nanosatellite Bus, devoted to the study of star brightness and formation ﬂying, respectively. Novel low-cost testing procedures are developed and used to characterize satellite sensor and actuator performance. The algorithm governing the pointing of CanX-4&5 is enhanced based on preliminary simulation results. A linear-time invariant controller architecture, applicable to both BRITE and CanX-4&5, is designed based on simulation of several competing controllers. Testing information is combined with control laws and controller to simulate the attitude performance of the satellites throughout their missions.