VictorJuiz/thesis huggingface dataset:
Compensatory Responses to Copulatory Organ Damage in the Western Black Widow
Keywords: regeneration
black widow

Experimental alterations of morphological traits during development can reveal life history tactics and resource allocation patterns. I examined effects of amputation of a structure directly involved with mating compared to one that is less associated with fitness. I amputated one of the paired external copulatory organs (palps) of juvenile male black widow spiders Latrodectus hesperus), and compared changes in life history traits and fitness to males with amputated legs and controls. I show that palps are more likely to be regenerated than legs, smaller juveniles are more likely to regenerate, and mating success is adversely affected in all adults that suffered early amputation. The pre-existing relationship between juvenile size and development was a critical determinant of regeneration, however no life history costs of regeneration were evident. I conclude that plasticity in life history facilitates regeneration, and that this may mask trade-offs involved in compensatory effects at the population level.
Structural Integrity is Essential for the Replication of the Virusoid RNA of Lucerne Transient Streak Sobemovirus
Keywords: LTSV
Virusoid

Lucerne transient streak sobemovirus (LTSV) supports the replication of a small, 322-nucleotide, untranslated virusoid (vLTSV) that has an extensively base-paired, viroid-like structure. Since vLTSV does not code for its own proteins or share sequence homology with its helper virus (LTSV), it is presumed that it uses structural motifs to signal the helper virus (and host) machinery for its replication. In order to elucidate these structural domains, insertion-deletion mutations were introduced to disrupt the secondary structure. Infectivity assays of these mutants showed that they were all lethal, except a 9-nucleotide, palindromic insertion, which preserved the overall rod-like structure of the virusoid. Sequence analysis of cDNA clones prepared from progeny virusoid RNA revealed that the palindromic sequence was replicated up to twelve days of infection but discarded afterwards. Results indicate that vLTSV has an optimum size and secondary structure for replication and packaging within the LTSV helper virus.
The Social Democratic Future of Saskatchewan: An Analysis of the Electoral Geography of Saskatoon and Regina, Saskatchewan in 2003 and 2007
Keywords: Electoral Geography
Voting Behaviour and Space

In November 2007 the right of centre Saskatchewan Party defeated Saskatchewan’s social democratic party, which had been in government for seventeen years. Unlike previous defeats, the New Democratic Party’s (NDP) loss in 2007 clearly showed that a new intra-urban political polarization in Saskatoon and Regina had emerged with the outer suburbs abandoning the NDP and the core areas maintaining previous levels of support. This study employs correlation analysis and logistic and linear regression analysis, using survey data from the 2003 and 2007 general election campaigns from Saskatchewan. Urban zones are constructed based on the morphological (urban form) hypothesis in order to create categories for spatial analysis. The different types of urban places are analyzed incorporating survey and Statscan data. Statistically significant differences between the urban zones are discussed in light of possible mechanisms found in the literature in order to explain recent political turns in Saskatchewan.
The Effect of Scale Centredness on Patient Satisfaction Responses
Keywords: Likert Scale
Rating Scale Options

High satisfaction rates and the lack of response variability are problematic areas in survey research. An important area of methodological concern for self-report survey is the sensitivity and reliability of the instrument. This research examines the effects of a positive (right) centred scale on the distribution and reliability of satisfaction responses in a positive respondent population. A total of 216 participants were randomly assigned to one of the following three experimental Likert scale conditions: 5–point equal interval balanced scale; 5–point positive (right) packed scale; 5–point positive (right) centred scale. The distribution of responses occurred in the direction hypothesized. Comparable discrimination was found across the three conditions. Although, the study findings did not prove to be significant, the equal interval balanced scale produced the lowest mean score, contrary to previous research findings.
A Survey of Functional Retroposed Genes: H. sapiens, M. musculus, D. melanogaster, and C. elegans
Keywords: Retrogene
Chromosome X
Homo sapiens
Mus musculus
Drosophila melanogaster
Caenorhabditis elegans
MSCI
Selection
Intrachromosomal
Interchromosomal

Retrogenes are functional genes that are created through retroposition, whereby mature mRNA is reverse-transcribed and re-integrated into the genome. In this study, the following objectives were accomplished: (i) intrachromosomal- and interchromosomal-retroposed genes were located in H. sapiens, (ii) interchromosomal-retroposed genes were located in M. musculus, D. melanogaster, and C. elegans. To date, this is the first assay for intrachromosomal-retroposed genes in H. sapiens and interchromosomal-retroposed genes in C. elegans. Biases discovered include excess interchromosomal generation of retrogenes by chromosome X in H. sapiens, M. musculus, and D. melanogaster. Selection pressure created by the inactivation of the X chromosome during male meiosis appears to be at least partially responsible for this phenomenon. In addition, excess interchromosomal recruitment of retrogenes by chromosome X was observed in H. sapiens. The driving force appears to be an interplay between selection for female-beneficial genes and selection for male-beneficial genes. No other chromosome biases were discovered.
Identifying Protein Partners of the Neuronal Transmembrane Protein NETO2
Keywords: Neuroscience

The neuronal transmembrane proteins Neto1 and Neto2, along with different protein partners, perform multiple roles in diverse processes including axon guidance in the developing nervous system and synaptic plasticity in the adult brain. My project focuses on identifying the membrane bound interacting partners of Neto2 using Membrane Yeast Two Hybrid (MYTH). By performing MYTH screens for the Neto2 molecule using human adult and embryonic whole brain cDNA libraries, I have identified several novel membrane bound putative interacting partners including, VAMP associated protein B (VAPB) and Glutamate transporter EAAT3-associated protein (GTRAP3-18), which play diverse functions during the glutamatergic neurotransmission. Initial studies to validate these interactions in vivo are currently underway by co-immunoprecipitation approach using mouse brain tissue. If these two candidate proteins are confirmed to be true interactors, it will open important avenues of research for the Neto2 protein during excitatory neurotransmission in the mammalian central nervous system.
A Hierarchical Description Language and Packing Algorithm for Heterogenous FPGAs
Keywords: FPGA
CAD
Packing
Clustering
Field-Programmable Gate Arrays
Computer-Aided Design
Architecture

The complexity of Field-Programmable Gate Array (FPGAs) logic blocks have undergone constant evolution to the point where both the basic soft logic blocks that implement combinational logic and the fixed-function hard blocks contain complex interconnects, hierarchy and modes. The goal of this thesis is to both support that complexity and enable future architecture exploration of even increased complexity and new kinds of hard functionality. To accomplish this, a Computer-Aided Design (CAD) flow that can map a user circuit to an FPGA with these complex blocks is needed. We propose a new language that can describe these complex blocks and a new area-driven tool for the packing stage of that CAD flow. The packing stage groups components of a user circuit into the complex blocks available on the FPGA. We conduct experiments to illustrate the quality of the packing tool and to demonstrate the newly-enabled architecture exploration capabilities.
CyborGlogger: A Computational Framework for Real-time CyborGlogging
Keywords: CyborGlogger
cameraphone
Glogger
Lifelong
lifelong experience capture
j2me
symbian
iphone
mobile phones
sift
wearable
passive capture
sousveillance
equiveillance

CyborGlogs are lifelong log files of personal experiences that are captured without conscious thought or effort. By creating cyborglogs on a continuous basis, we can enable various novel applications where the lifelong records are used as memory aids or for personal safety. This thesis presents the development of a mobile application that provides the tools to instantly capture, archive, recall, and share our personal experiences on widely available cameraphones. To achieve this goal, a client-server computational framework is designed and implemented to support real-time interaction among the users. Three fully functional prototypes supporting three major mobile platforms (J2ME, Symbian, and iPhone) are presented to show the feasibility and flexibility of this framework. Finally, this thesis shows an early prototype which demonstrates the idea of mediated reality on cameraphones using various integrated sensors. This prototype explores the possibilities of developing truly intelligent wearable applications on mobile devices in the future.
Developmental Change in Frontal Neuronal Oscillations during Response Inhibition
Keywords: Neuroscience
Child development

The present study was designed to investigate developmental effects on cortical oscillations during response inhibition. EEG data were collected from 42 normally developing children (8 - 18 years old) while they performed Go/No-go tasks. We examined EEG power in alpha (8 - 12Hz) and theta (4 - 7Hz) frequency bands during No-go trials. Results showed that alpha and theta power decreased during baseline, and theta power enhancement during response inhibition (200 – 400ms post-stimulus) increased, with age. Also, baseline power was found to be negatively, and theta power enhancement during inhibition positively, correlated with behavioral performance. Importantly, when the effects of brain measures on behavioral performance were considered, age effects on performance became non-significant, suggesting a mediator role for brain activation. These findings indicate that, as children age, the brain cortex becomes less activated before inhibitory tasks but more activated during tasks, suggesting a more efficient allocation of neural resources.
Interproximal Papillae Adjacent to Single Implant Crowns in the Aesthetic Zone: Clinical and Radiographic Findings from a Multi-private Practice Based Research Network (PBRN) and Post-graduate Prosthodontics/Periodontology Residency Programs
Keywords: implant
papilla

This study was designed to determine if the following two variables influence the predictability of the presence of the interproximal papilla between single implant supported crown adjacent to a natural tooth: a) the vertical measurement from the crest of bone on the natural tooth to the contact point, and b) the horizontal measurement from the platform of the implant to the adjacent tooth root. Retrospective data from a multi-private practice based research network (PBRN) and from a graduate teaching institution were analyzed specific to the maxillary anterior aesthetic zones. 116 patients who had 139 dental implants restored for at least 6 months, with mesial and/or distal sites (N= 253) were included in the analysis. Assessments of the implant position based on osseous crestal topography were conducted using standardized radiographs which were digitized and interpreted with “Access” software. The gingival papilla morphology was assessed using the Jemt Papillary Index from calibrated digital clinical photographs. Contrary to previously published data, our results indicate that the presence of interproximal papillae is independent of the vertical and horizontal measurements investigated.
Study of a Semiconductor Nanowire under a Scanning Probe Tip Gate
Keywords: Nanowire
Scanning Probe

Nanowires are sensitive to external influences such as surface charges or external electric fields. An Atomic Force Microsope (AFM) is modified to perform back gating and tip gating measurements in order to understand the interaction between an external field, and surface charge and nanowire conductance. A 2D finite element method (FEM) model is developed to simulate the measured conductance. The model shows that surface states play a critical role in determining nanowire conductance. A 3D FEM model is developed to examine the influence of the AFM tip on the lateral resolution of the AFM tip in the electrostatic measurement. The radius of the AFM tip determines the lateral resolution of the tip. However, carrier concentration in the nanowire establishes a lower limit on the lateral resolution, for small tip radii. These results enable one to optimize Scanning Probe Microscopy experiments as well as inform sample preparation for nanowire characterization.
Cellular and Molecular Mechanism Underlying the Effect of Low-magnitude, High-frequency Vibration on Bone
Keywords: bone
mechanotransduction
osteocyte
osteoclast
mesenchymal stromal cell
whole body vibration
low-magnitude, high-frequency vibration

An emerging non-pharmacological treatment for bone degenerative diseases is whole body vibration (WBV), a mechanical signal composed of low-magnitude, high-frequency (LMHF) vibrations that when applied to bone, have osteogenic and anti-resorptive effects. Currently, the cellular and molecular mechanism underlying the effect of WBV on bone is unclear. In this study, we investigated the response of osteocytes, the putative mechanosensor in bone, under LMHF vibration. As bone cells differentiate from mesenchymal stromal cells (MSCs), we also studied the osteogenic differentiation of rat MSCs in the presence of vibration loading. We found that vibrated osteocytes show gene and protein expression changes suggestive of an anti-osteoclastogenic response, and secrete soluble factors that inhibit osteoclast formation and activity. In contrast, rat MSCs showed moderate to no response to LMHF vibration during osteogenic differentiation. Our data suggest that in vivo effects of LMHF vibration are mediated through mechanosensing and biochemical responses by osteocytes.
Synthesis of High Purity Silicon from Rice Husks
Keywords: silicon
rice husks
synthesis
reduction
leaching
RHA
high purity
solar grade silicon
magnesium
refining
Quantitative XRD
ICP

Impurity optimized silicon is needed for the advancement of terrestrial photovoltaic power generation. In this study the possibility of producing solar grade silicon from rice husks has been pursued. An integrated process flowsheet was developed and practiced that included initial leaching, reduction of Rice husk ash (RHA) and post-reduction purification of silicon. Metallothermic reduction of purified RHA with magnesium was investigated within the temperature range of 500-950 oC. The reduction product was purified by two stage acid leaching sequence. Analysis of the final silicon powder product by XRD and ICP-OES showed crystalline silicon with boron content to be less than 3ppm- corresponding to reduction by a factor greater than 10, whilst the phosphorus content was reduced by a factor of over 20 and reaching less than 73ppm. The effects of temperature, magnesium amount and leaching agents were optimized in this study. A one step test melting was also carried out to convert the silicon powder into silicon chunks.
Perturbation Evoked Balance Control Reactions in Individuals with Stroke
Keywords: Balance
Stroke
Posture

Individuals with stroke suffer from impaired balance that increases their risk of falling. Controlling reactive balance is essential to maintaining stability. The objective of the first study was to identify the role of pre-perturbation stance asymmetry on limb preference for reactive stepping in healthy young adults. This study demonstrated that steps taken with a pre-loaded limb are short, directed laterally and have a rapid swing time. The objective of the second study was to investigate the challenges of reactive stepping among individuals with stroke. This study demonstrated that participants primarily execute reactive stepping with their non-paretic limb, although those steps are highlighted by delays in timing and increased incidence of multiple stepping compared to healthy controls, even though all participants had very good clinical balance scores. Outcomes from this thesis present the need for improved clinical assessment of reactive balance control to help reduce the incidence of falling following stroke.
Ontario’s Energy - A Review of the Present and a Proposal for Future Development
Keywords: Ontario Supply Mix
Power optimization

The work presents a framework for analyzing complex decision making in policy from the perspective of planning power supply mix for Ontario. Concepts of sustainability are introduced and analyzed followed by an in-depth view of two case studies. The first analyzes the power supply mix for Ontario and the second analyzes policy impacts in Germany and Denmark. A linear programming model, including energy storage is then developed that would yield an optimized sustainability based development policy for electricity production in Ontario. Future work is recommended to calibrate and run the model. The analysis discusses the new model in relation to the first case study and provides a mechanism to evaluate tradeoffs traditionally unquantifiable, to yield a strategic plan for electricity development in Ontario.
Peace Through Health: Theory and Practice of the International Pediatric Emergency Medicine Elective (IPEME)
Keywords: Peace Through Health
Medical Elective
Collaboration
Peacebuilding
Evaluation
IPEME

This thesis seeks to evaluate the International Pediatric Emergency Medicine Elective (IPEME) as a case study of a peace-through-health initiative. Using the reasoning of Scolnik (2006), IPEME is first evaluated in terms of narrow, short-term outcomes and subsequently considered in terms of the greater body of peace-through-health work. A novel evaluation tool was designed to examine change in students’ ethical and professional attitudes over the course of the four-week elective. Supplementary qualitative data was collected to shed light on evaluation findings and provide insight into the advantages and disadvantages of the IPEME curriculum. Ethics and professionalism were defined in terms of the WHO 5 Star Global Criteria for Global Doctors conceptualized by the World Health Organization (Boelen, 1996). This research discusses these findings in light of the study’s limitations and considers their implications for IPEME as a medical elective and for its contribution to the greater body of peace-through-health work.
An Active Reconfigurable Reflectarray Antenna
Keywords: antenna
reflectarray antenna
active integrated
reconfigurable
amplifying
beam steering

This thesis focuses on a type of antenna known as the reflectarray antenna. In particular, it looks at the design of an active reconfigurable reflectarray antenna, which has not received much attention in the reflectarray community. Potential applications include deployment as a high gain, reconfigurable antenna for communication links, and as a spatial power combiner. The reflectarray element is an aperture-coupled patch that accepts a linearly polarized wave, phase shifts and amplifies the guided-waves in the transmission lines, and then re-radiates an orthogonally polarized wave. Stability analysis of the element, experimental results of the designed phase shifter and simulation and experimental results of the element are presented. Fabrication details of a 48 element reflectarray and challenges faced during experimental characterization of the elements are also discussed. The two dimensional beamforming capability and amplifying nature of the array are successfully demonstrated and veri fied, indicating robustness to phase errors and oscillating elements.
The Role of the Anterior Cingulate Cortex and Neurabin in Anxiety- and Depression-like Behaviours
Keywords: anterior cingulate cortex
neurabin
anxiety
depression
siRNA
microinjection

Neurabin, a cytoskeletal protein, has been shown to be required for normal dopamine signalling, and dopaminergic systems have been previously implicated in the pathophysiology of anxiety disorders, including generalized social anxiety disorder. And results from neuroimaging studies have implicated the anterior cingulate cortex (ACC) in depression and anxiety disorders. However, lesion studies have failed to produce the expected deficits. Here, we demonstrate that the injections of muscimol and midazolam into the ACC reduced anxiety- and depression-like behaviours, and that complete absence of neurabin reduced anxiety-like behaviour but increased depression-like behaviour. However, reduction of neurabin by injecting neurabin-targeted siRNA into the ACC reduced anxiety-like behaviour but did not affect depression-like behaviour. This study provides evidence that the imbalance of excitatory and inhibitory activity in the ACC alters affective disorders, and that neurabin may be critical for the modulation of these behaviours.
Misfolding of Particular PrP and Susceptibility to Prion Infection
Keywords: Prion protein
prion disease
prion susceptibility
protein misfolding
circular dichroism
analytical ultracentrifugation

Pathogenesis of prion diseases in animals is associated with the misfolding of the cellular prion protein PrPC to the infectious form, PrPSc. We hypothesized that an animal’s susceptibility to prions is correlated with the propensity of an animal’s PrPC to adopt a β-sheet, PrPSc-like, conformation. We have developed a method which uses circular dichroism (CD) to directly calculate the relative population of PrP molecules that adopt a β-sheet conformation or the ‘β-state’, as a function of denaturant concentration and pH. We find that the PrP from animals that are more susceptible to prion diseases, like hamsters and mice, adopt the β-state more readily than the PrP from rabbits. The X-ray crystal structure of rabbit PrP reveals a helix-capping motif that may lower the propensity to form the β-state. PrP in the β-state contains both monomeric and octameric β-structured species, and possesses cytotoxic properties.
Protein-protein Interaction Between Two Key Regulators of One-carbon Metabolism in Saccaharomyces cerevisiae.
Keywords: One-Carbon Metabolism
Gene Regulation

One-carbon metabolism is an essential process that is conserved from yeast to humans. Glycine stimulates the expression of genes in one-carbon metabolism, whereas its withdrawal causes repression of these genes. The transcription factor Bas1p and the metabolic enzyme Shm2p have been implicated in this regulation. I have shown that Bas1p physically interacts with Shm2p through co-immunoprecipitation. Using chromatin immunoprecipitation (ChIP), I have also shown that the interaction between Bas1p and Shm2p occurs at the promoter of two genes in the one-carbon metabolism regulon and that the binding of Shm2p requires Bas1p. Using a yeast-two hybrid system, I have systematically truncated Bas1p from the C-terminal end to find a region responsible for the interaction with Shm2p. My data suggest that Shm2p is directly bound to Bas1p at the promoters of glycine regulated genes where it regulates the transcriptional activity of Bas1p in response to changes in glycine levels.