VictorJuiz/thesis huggingface dataset:
Counteractive Control and the Dieter: The Role of Food Cue Specificity in Food Selection and Eating Behavior

Research on counteractive control theory suggests that exposure to food cues should bolster the dieting goal in restrained individuals. However, other research has found food cues to increase eating. The present study investigates whether cue specificity influences whether counteractive control or hyper-responsiveness to food cues takes precedence in dieters’ food selection and eating behavior. Restrained eaters were assigned to view a cookie, cake, or flower cue, then they selected a snack to take (apple or cookie). Participants also had an opportunity to eat cookies. Results showed that restrained participants exposed to the cake cue chose the apple more often than those receiving any other cue; exposure to a tempting cue not specific to the snack offered elicited counteractive control. However, participants exposed to either food cue ate more cookies than those exposed to the neutral cue. The role of food cue specificity in counteractive control and its limits are examined.

Keywords: Counteractive Control
Dieting
Food Cues
Advisor: Polivy, Janet
Molecular Mechanisms Of Neuroinflammation Following Global Cerebral Ischemia: The Role of Hypothermia Therapy

Hypothermia therapy (HT) is used clinically following global cerebral ischemia (GCI) but its therapeutic mechanisms are not completely understood. An elucidation of such mechanisms may lead to novel therapeutic approaches that improve patient outcome. Using a murine model of GCI, we determined the effect of HT on the expression of inflammatory proteins in the hippocampus and serum. We also examined its effect on microglia/macrophage activation and neurodegeneration in the brain at 72 hours following ischemia, and its effect on long-term spatial memory/learning and contextual fear response. GCI led to increased neurodegeneration and microglia/macrophage activation in the hippocampus, and increased IL-1β and KC protein expression in the hippocampus at 72 hours. Hypothermia therapy attenuated these inflammatory responses. It also improved spatial learning/memory at 7 and 21 days, and preserved contextual fear response 21 days post-ischemia. Hypothermia therapy attenuated the post-ischemic inflammatory response, protected hippocampal neurons, and preserved long-term memory and learning.

Keywords: hypothermia
cerebral ischemia
inflammation
neurodegeneration
cardiac arrest
cytokines
chemokines
adhesion molecules
spatial learning and memory
fear learning and memory
Advisor: Hutchison, James
Evolution of cps Loci in Vibrio vulnificus

Vibrio vulnificus is an opportunistic human and animal pathogen with the highest death rate of any foodborne disease agent. The capsular polysaccharide (CPS) is essential for virulence. Over 100 CPS types (carbotypes) have been identified among natural isolates, yet little is known about the genetic mechanisms that drive such diversity. Chitin, the second most abundant polysaccharide in nature, induces competence in Vibrio species. We found that transformation frequency varies by strain and (GlcNAc)2 was the shortest chitin-derived polymer capable of inducing competence. We confirmed that V. vulnificus can undergo chitin-dependent carbotype conversion following the uptake and recombination of complete cps loci from exogenous genomic DNA. The acquisition of a partial locus was also demonstrated when internal regions of homology between the endogenous and exogenous loci existed. Thus, the same mechanism governing the transfer of complete cps loci also contributes to their evolution by generating novel combinations of CPS biosynthesis genes.

Keywords: Vibrio vulnificus
CPS
Horizontal gene transfer
Advisor: Rowe-Magnus, Dean
Inhibitory Account of Semantic Interference Resolution in Memory: Suppression of Competing Information

Using a novel paradigm, we provide direct evidence for the role of inhibition during semantic interference resolution in memory. In Experiment 1, target words were primed via a naming task. Then, a cue word prompted participants to generate either a meaningfully related or unrelated word. Producing an unrelated word should require suppression of the cue's closest associates, which were the primed targets. Finally, participants read a list of words including the suppressed targets. Participants were slower to name targets in the unrelated condition than in the related condition, indicating that generating an unrelated word required suppression of competitors. Experiment 2 eliminated the initial priming phase, and a robust suppression effect was observed. Both studies showed that naming targets in the unrelated condition was even slower than controls. These results reflect that resolving semantic competition entails suppression of rejected competitors to below baseline levels, supporting an inhibitory account of interference resolution.

Keywords: interference
inhibition
suppression
Advisor: Hasher, Lynn
Characterization of Myometrial Cytokine Expression and Leukocyte Infiltration During Term and Preterm Labour in the Mouse

Studies indicate an association between both term labour (TL) and preterm labour (PTL) and the presence of uterine inflammatory cytokines and leukocyte infiltration. We hypothesized that peripheral leukocytes are recruited to uterine tissues by locally produced cytokines where they contribute to the initiation of TL and PTL. The cytokine expression profile was analyzed using an in vivo mouse model of gestation and two PTL models (Lipopolysaccharide- and RU486-induced). Myometrial neutrophil and macrophage infiltration was also studied. My results demonstrate that macrophage infiltration precedes neutrophil infiltration during late gestation and that both leukocyte subsets increase during PTL and further increase post partum. These changes in leukocyte numbers are associated with significant changes in multiple myometrial cytokines with TL and RU486-induced PTL showing similar cytokine profiles. Importantly, post partum involution, the process by which the uterus completes the reproductive cycle and returns to its pre-pregnant state, appears similar in all three models.

Keywords: Labour
Leukocytes
Cytokines
Preterm Labour
Lipopolysaccharide
Myometrium
RU486
Neutrophil
Macrophage
Post partum
Advisor: Lye, Stephen J.
Chemistry and Corrosion Mechanisms of Steels Embedded in High-density Slag Concrete for Storage of Used Nuclear Fuel

The chemistry and corrosion mechanisms associated with reduced sulfur compounds such as calcium sulfide, present in ground granulated blast-furnace slag (GGBFS), have been studied in high-density concrete, mortar and simulated pore-water environments. The high-density concrete and mortar samples were produced to replicate the high-density GGBFS concrete, in the dry storage containers (DSCs), used for radiation shielding from used nuclear fuel. Electrochemical measurements on embedded steel electrodes in high-density GGBFS concrete and mortar samples, showed that sulfide is capable of consuming oxygen to create a stable, reducing environment, though not in all cases, and the high-frequency electrolyte resistance increases with hydration time. Ion chromatography on simulated pore-water environments determined that thiosulfate is quite kinetically stable as a sulfide oxidation product and magnetite is capable of oxidizing sulfide. Microscopy has also been used to provide visual evidence of GGBFS hydration and elemental quantification of the hydrating microstructure in different environments.

Keywords: nuclear
corrosion
used fuel
chemical engineering
concrete
slag
nuclear waste management
steel
sulfide
thiosulfate
cement
GGBFS
steel corrosion
radioactive waste
ion chromatography
electrochemistry
microscopy
impedance
OPC
mortar
sulfate
magnetite
hematite
aggregates
Advisor: Newman, Roger C.
Promotion of the Availability and Accessibility of Misoprostol under the CEDAW: Postpartum Haemorrhage among the Rural Women of the Kyrgyz Republic

Maternal mortality in Kyrgyzstan is a discrimination of women not only based on sex, but also on rural/urban setting. Rural women are most likely to die of haemorrhage than urban women in Kyrgyzstan. Postpartum haemorrhage constitutes 45 per cent of all maternal deaths in Kyrgyzstan. This work concentrates on the obligations of Kyrgyzstan under articles 12 and 14.b of the Convention on Elimination of all Forms of Discrimination against Women (CEDAW). The work analyses the nature and scope of state obligations under respective articles. Kyrgyzstan has obligations to respect, protect and fulfill rural women’s human rights to address discriminations against rural women, provide appropriate health services and ensure availability and accessibility of misoprostol to rural women. Misoprostol is more suitable to the conditions of rural area than traditionally used oxytocin. Therefore, the availability and accessibility of rural women to misoprostol will prevent avoidable maternal deaths in haemorrhage.

Keywords: CEDAW
postpartum haemorrhage
article 12 on health
article 14 on rural women
Misoprostol
Kyrgyz Republic
Advisor: Cook, Rebecca J.
Morphine-induced Locomotion Increases following Viral Transfection of M5 Muscarinic Receptor Genes in the Ventromedial Hypothalamus of Wild-type Mice

Excitatory M5 muscarinic acetylcholine receptors are expressed at the highest level in the brain, in the ventromedial hypothalamus (VMH). M5 knockout (KO) mice emit fewer ultrasonic vocalizations (USVs) during mating, and show 40-50% lesser morphine-induced locomotion as compared to wild-type (WT) mice. Following viral transfection of M5 muscarinic receptors in the ventral tegmentum (VTA), KO mice depict restored mating-induced USVs and enhanced morphine-induced locomotion. The VMH is important for motivational processes, such as, feeding and producing USVs in rats. With a Herpes simplex virus (HSV), the M5 receptor gene was transfected into the VMH of WT mice. M5 transfection into neurons of the VMH increased locomotion in mice injected with 10mg/kg morphine. When a D2-selective dopamine blocker was injected into the same mice, locomotion was drastically reduced. There were no significant differences in amount of USVs produced. VMH may exert its effects on morphine through a DA dependent VTA pathway.

Keywords: muscarinic
ventromedial hypothalamus
Advisor: Yeomans, John S.
Attentional Selection and Reduced Interference Improve Visual Short-term Memory in Mild Cognitive Impairment

Visual short-term memory (VSTM) is a vital cognitive ability, allowing us to hold online the contents of visual awareness. Healthy older adults have reduced VSTM capacity compared to young adults; however recent evidence suggests that their performance may be improved by the use of a retroactive cue (“retro-cue”). The retro-cue reduces interference from irrelevant items within VSTM. Mild cognitive impairment (MCI) patients have reduced VSTM performance, compared to healthy older adults. Here, we examined whether the use of a retro-cue would increase VSTM capacity in MCI patients. By presenting a retro-cue after a to-be remembered array, we direct attention to the to-be probed location, which reduces interference from other items that are no longer relevant. The present findings suggest that VSTM capacity per se is not compromised in MCI patients, but these patients may be more susceptible to the effects of interference.

Keywords: Memory
Mild Cognitive Impairment
Advisor: Barense, Morgan
Assessing Primary Care Physicians’ Attitudes Towards Adoption of an Electronic Tool to Support Cancer Diagnosis

The objective of this study was to assess Primary Care Physicians’ attitudes towards adoption of the Diagnostic Assessment Program-Electronic Pathway Solution (DAP-EPS), an electronic tool for improving cancer diagnostic processes. The implementation of DAP-EPS is a provincial activity supported by Cancer Care Ontario in collaboration with the Canadian Cancer Society. We conducted an online survey of Ontario PCPs. To guide our study, we used an integrated theoretical framework combining the Technology Acceptance Model and Diffusion of Innovation. Study results suggested a strong influence of perceived usefulness of the DAP-EPS tool on physicians’ attitudes towards adoption of the tool. The results also found that perceived usefulness was more important than perceived ease-of-use within the PCP context. The study revealed that perceived usefulness is the main predictor of physicians’ attitudes. The findings also suggested that the management and implementation team should emphasize the usefulness of the DAP-EPS to increase adoption among PCPs.

Keywords: Cancer Care
e-Health
Physicians
Adoption
Advisor: Wiljer, David
Place Cell Activity in Disc1-L100P Mutant Mice

DISC1 is an established susceptibility gene for schizophrenia. To gain insight on the neural mechanisms responsible for hippocampal deficits in schizophrenia, we sought to characterize place cell activity and theta rhythm in our Disc1-L100P mouse strain that we have previously shown to express deficits in spatial working memory. Our findings suggest that the rate code of place cells is intact. We found that Disc1-L100P mice have deficits in theta rhythm, increased neural noise, and lower levels of PV+ interneurons in the hippocampus. Our findings are supportive of impaired temporal coding in Disc1-L100P place cells. We found that Disc1-L100P place cell waveforms were broader than those of wild-type mice and putative interneuron waveforms were narrower. These findings suggest that ion-channel function and expression in the hippocampus is altered in Disc1-L100P mice. In schizophrenic subjects deficits in working memory are associated with aberrant oscillatory activity, increased noise, and lower PV+ interneuron expression.

Keywords: Schizophrenia
Place Cells
Advisor: Roder, John C.
Circulating Microparticles in Response to Decompression Stress

The effect of decompression stress on circulating microparticles (MPs) from leukocytes (LMP), platelets (PMP), and endothelial cells (EMP) was investigated in fifteen male naval clearance divers. Venous blood samples were obtained 30 min before and 75 min after exposure to 81msw for 20 min. MPs were isolated by differential centrifugation and immunophenotyped using multiparameter flow cytometry. Venous gas emboli (VGE) were assessed using Doppler ultrasound every 40 min post-dive and subsequently graded using the Kisman Integrated Severity Score (mean KISS=21.92, indicating moderate level of VGE). Following the dive there was increased expression of CD41a, CD106, CD62P and CD31 on MPs, while CD45 and CD141 expression decreased. A positive correlation was found between KISS and CD41a expression post-dive. These results indicate that decompression stress activated platelets, producing PMPs and resulting in potential vascular disruption or injury. The inclusion of MP measures in future DCS-related research may help identify biomarkers of DCS.

Keywords: microparticles
decompression stress
flow cytometry
Advisor: Scott, Thomas
Identification and Development of Individualized Access Pathways Based on Response Efficiency Theory

Despite the evident advantages of assistive technologies, many are still abandoned within the first few months of use. The key to changing this may lie in the assessment process, which has been described as the most consequential phase in the provision of assistive technology [14]. The purpose of this research was to create a protocol for the assessment and delivery of individualized access technologies based on the concepts of response efficiency theory. The protocol was applied with three children, ages 12 to 14, who were seeking new access technologies. The results suggest that a protocol based on this theory will result in a technology that is appropriate to the user, and as a result will be less likely to be abandoned and will contribute to goal achievement and potentially improve participation.

Keywords: assistive technology
access
assesment
outcome measures
Advisor: Chau, Tom
Mechanisms underlying Metformin-induced Secretion of Glucagon-like Peptide-1 from the Intestinal L-cell

The incretin hormone glucagon-like peptide-1 enhances glucose-dependent insulin secretion and is therefore a most attractive therapeutic approach for the treatment of Type 2 Diabetes Mellitus. The anti-diabetic drug, metformin, has previously been shown to increase circulating levels of GLP-1, although its mechanism of action is currently unknown. Neither metformin nor AICAR (activators of AMPK) directly stimulated GLP-1 secretion from the L-cell in vitro. However, oral treatment of rats with metformin enhanced plasma levels of active and total GLP-1, independent of GLP-1 degradation. Furthermore, pre-treatment with the general muscarinic antagonist, atropine, or the M3 antagonist, 4-DAMP, decreased metformin–induced GLP-1 secretion, while M1 and M2 antagonists did not. Chronic bilateral subdiaphragmatic vagotomy had no effect, while the GRP antagonist, RC-3095, reduced metformin-induced GLP-1secretion. Therefore, I conclude that metformin-induced GLP-1 secretion occurs in part through the parasympathetic nervous system, the M3 and GRP receptors, but is independent of the vagus nerve.

Keywords: metformin
GLP-1
Advisor: Brubaker, Patricia
Detecting and Classifying Cognitive Activity Based on Changes in Cerebral Blood Flow Velocity

Individuals with severe physical impairments have a reduced ability to communicate through movement and speech. We investigated transcranial Doppler ultrasound as a potential measurement modality for a novel brain-computer interface. It was hypothesized that cognitive activity would result in detectable changes in cerebral blood flow velocity within the middle cerebral arteries. Nine able-bodied participants alternated between rest and two different mental activities - silent word generation and mental rotation. Two analyses were performed to assess the feasibility and practicality of a TCD-based brain-computer interface. Both mental activities were independently differentiated from rest with high accuracy. Intuitive time-domain features were sufficient for classification. Data transmission rate was quadrupled by differentiating all three classes simultaneously using shorter state durations. Transcranial Doppler ultrasound can be used to automatically detect cognitive activity and may be useful as the basis of a brain-computer interface.

Keywords: brain-computer interface
transcranial doppler
Advisor: Chau, Tom
No to Rawlsian Public Reason and Yes to the Enlarged Mentality: An Affirmative Role for Moral and Religious Arguments in Canadian Public Discourse in light of Charter Values

This paper examines two different theories in relation to the optimal modes of public deliberation about constitutional values and the public good in the context of democratic pluralism: Rawlsian Public Reason and Nedelsky’s Enlarged Mentality. I challenge Rawlsian public reason’s claim to epistemic abstinence, autonomy and its claim to reflect a political conception of justice by examining certain contradictory aspects of its theoretical rendition. I argue that significant aspects of the picture of democracy that Rawlsian public reason reflects are unempirical. I argue that Rawlsian public reason’s concept of bracketing moral and religious argumentation from public deliberation is unjustifiable, unattainable and derogates from Canadian constitutional values. I proffer that Nedelsky’s enlarged mentality is preferable as it is more realistic and consonant with Canadian constitutional values. I argue that Nedelsky’s enlarged mentality is facilitative of genuine and meaningful dialogic exchange in spite of difference whilst managing the risk of democratic instability.

Keywords: law, religion and public discourse
Advisor: Emon, Anver
Separating the Functions of the Medial and Lateral Entorhinal Cortex: Differential Involvement in Spatial and Non-spatial Memory Retrieval

Anatomical connectivity and single neuron coding suggest a dissociation of information representation within the lateral and medial entorhinal cortex, a brain region with widespread connections to cortical areas. We aimed to expand this idea by examining differential contribution of these two sub-regions to the retrieval of non-spatial and spatial memory. Inactivation of lateral, but not medial regions severely impaired the retrieval of recently and remotely acquired non-spatial memory while spatial memory remained intact. To link functioning of the lateral entorhinal cortex with the known roles of the hippocampus and medial prefrontal cortex for memory retrieval, communication with these two regions was detected as synchronized oscillations in local field potentials. We found that stronger communication between the lateral entorhinal and prefrontal cortex during stimulus-free periods correlated with better memory performance. The lateral entorhinal cortex therefore may serve as a gateway of memory-related information between the medial prefrontal and other cortical regions.

Keywords: memory
entorhinal cortex
Advisor: Takehara-Nishiuchi, Kaori
Hip Resurfacing Arthroplasty: Investigating the Femoral Component in the Sagittal Plane

The outcomes of hip resurfacing arthroplasty are largely dependent on prosthesis positioning. The biomechanics of notching, accurate measurement of femoral implant version and the use of computer navigation of the Birmingham Hip Resurfacing procedure were studied in this work. First, biomechanical tests were conducted with varying notch sizes and femoral positions, and it was determined that anterior notching weakens the construct (p=0.027) when the femur is in flexion and less so when in single-leg stance (p=0.155). Second, three novel techniques were used by three observers to measure the implant version in a lateral radiograph to determine which displayed a more accurate intra-class correlation. The third study examined the role of computer navigation as a learning device for improving the accuracy of femoral implant positioning using a manual alignment jig to curtail sequelae associated with malalignment.

Keywords: Hip Resurfacing
Orthopaedics
Advisor: Schemitsch, Emil H.
Oxytocin-immunoreactive Neurons in the Paraventricular Nucleus of the Hypothalamus in Hetercephalus glaber: A Quantitative Analysis

The naked mole-rat (Heterocephalus glaber) demonstrates a strict social and reproductive hierarchy. Oxytocin (OXT) is a peptide hormone that acts both peripherally and centrally in the regulation of a number of sexual and social behaviours. The main area of central production of this peptide is the paraventricular nucleus of the hypothalamus (PVN). The present study characterized differences that exist in OXT neurons in this region. Breeders and subordinates from established colonies were sacrificed and brains were processed for OXT-immunoreactivity. Four further groups of paired animals underwent various social and hormonal manipulations (opposite-sex paired, same sex-paired, opposite-sex/gonadectomised paired, opposite-sex/vasectomized paired) and were also used for analysis. Results showed that subordinate naked mole-rats had significantly more OXT-immunoreactive neurons in the PVN than either breeders or paired animals that had been gonadectomised. However, no differences were found on measures of OXT cell volume. Possible functional significance of these differences is discussed.

Keywords: oxytocin
naked mole-rat
paraventricular nucleus of the hypothalamus
Hetercephalus glaber
Advisor: Homes, Melissa