VictorJuiz/thesis huggingface dataset:
Chronic Effects and Acute Physiological Response to Aerobic and Resistance Training in Patients Following Stroke Referred to a Cardiac Rehabilitation Program

There is compelling evidence that regular physical activity is likely to play a role in the secondary prevention of stroke and comorbid coronary artery disease. However, structured physical activity programs are not widely available for people following stroke. Cardiac rehabilitation programs (CRP) are well suited to provide exercise training following traditional stroke rehabilitation. However, people following stroke may be limited by a constellation of neurological deficits that may prevent them from effectively participating in and benefiting from an adapted CRP. Accordingly, the objectives of this work were to 1) examine the utility of cardiopulmonary exercise stress testing (CPET) for developing an exercise prescription in people ≥3 months post-stroke with mild/moderate motor impairments 2) determine ability to achieve minimal recommended exercise training levels reported to elicit health benefits during a single standard CR session following completion of a CRP 3) evaluate the physiological, and cognitive effects of a 24-week CRP of resistance and aerobic exercise and the effect of stroke-recovery-time. It was hypothesized that most patients (>50%) would reach a level of exertion on the CPET that would provide recommended exercise prescription target levels and that individuals would be able to systematically reach these target levels during a CR session. Moreover, the established exercise program would result in physiological and cognitive benefit independent of time-from-stroke. Study 1 demonstrated that most patients achieved a level of exertion during the CPET sufficient to inform an exercise prescription. In Study 2 patients with motor impairments were able to meet or exceed minimal recommended exercise target levels of intensity, duration and energy expenditure. In Study 3 a CRP yielded improvements over multiple domains of recovery (cardiovascular fitness, functional ambulation, sit-to-stand performance, and muscular strength). While those referred ≤1 year and >1 year post-stroke derived benefits from a CRP, those who started earlier (≤1 year) had greater improvements in ambulatory performance. In Study 4 combined aerobic and resistance exercise resulted in improvements in cognitive function. Change in cognition was positively associated with change in fat-free mass and change in anaerobic threshold. In summary people post-stroke are able to effectively participate in and benefit from an adapted CRP.

Keywords: Cerebrovascular Event
Exercise Therapy
Advisor: Brooks, Dina
The Dentate Gyrus of the Hippocampus: Roles of Transforming Growth Factor beta1 (TGFbeta1) and Adult Neurogenesis in the Expression of Spatial Memory

The dentate gyrus is a region that hosts most of the hippocampal cells in mammals. Nevertheless, its role in spatial memory remains poorly understood, especially in light of the recently-studied phenomenon of adult hippocampal neurogenesis and its possible role in aging and chronic brain disease. We found that chronic over-expression of transforming growth factor beta1 (TGFbeta1), a cytokine involved in neurodegenerative disease, results in several modifications of brain structure, including volumetric changes and persistent astrogliosis. Furthermore, TGFbeta1 over-expression affects the generation of new neurons, leading to an increased number of neurons in the dentate gyrus and deficits in spatial memory acquisition and storage in aged mice. Nonetheless, reducing neurogenesis via pharmacological treatment impairs spatial memory in juvenile mice but not in adult or aged mice. This suggests that the addition of new cells to hippocampal circuitry, and not the increased plasticity of these cells, is the most relevant role of neurogenesis in spatial memory. We tested this idea by modifying proliferation in the dentate gyrus at several ages using multiple techniques and evaluating the incorporation of newborn neurons into hippocampal circuitry. We found that all granule neurons, recently generated or not, have the same probability of being incorporated. Therefore, the number of new neurons participating in memory circuits is proportional to their availability. Our conclusion is that adult-generated cells have the same functional relevance as those generated during development. Together, our data show that the dentate gyrus is important for memory processing and that adult neurogenesis may be relevant to its functionality by optimizing the number of neurons for memory processing. The equilibrium between neurogenesis and optimal dentate gyrus size is disrupted when TGFbeta1 is chronically increased, which occurs in neurodegenerative pathologies, leading to cognitive impairment in aged animals.

Keywords: adult neurogenesis
transforming growth factor-beta
hippocampus
Dentate gyrus
cognition
Advisor: Frankland, Paul
A Framework for the Development of Scalable Heterogeneous Robot Teams with Dynamically Distributed Processing

As the applications of mobile robotics evolve it has become increasingly less practical for researchers to design custom hardware and control systems for each problem. This research presents a new approach to control system design that looks beyond end-of-lifecycle performance and considers control system structure, flexibility, and extensibility. Toward these ends the Control ad libitum philosophy is proposed, stating that to make significant progress in the real-world application of mobile robot teams the control system must be structured such that teams can be formed in real-time from diverse components. The Control ad libitum philosophy was applied to the design of the HAA (Host, Avatar, Agent) architecture: a modular hierarchical framework built with provably correct distributed algorithms. A control system for exploration and mapping, search and deploy, and foraging was developed to evaluate the architecture in three sets of hardware-in-the-loop experiments. First, the basic functionality of the HAA architecture was studied, specifically the ability to: a) dynamically form the control system, b) dynamically form the robot team, c) dynamically form the processing network, and d) handle heterogeneous teams. Secondly, the real-time performance of the distributed algorithms was tested, and proved effective for the moderate sized systems tested. Furthermore, the distributed Just-in-time Cooperative Simultaneous Localization and Mapping (JC-SLAM) algorithm demonstrated accuracy equal to or better than traditional approaches in resource starved scenarios, while reducing exploration time significantly. The JC-SLAM strategies are also suitable for integration into many existing particle filter SLAM approaches, complementing their unique optimizations. Thirdly, the control system was subjected to concurrent software and hardware failures in a series of increasingly complex experiments. Even with unrealistically high rates of failure the control system was able to successfully complete its tasks. The HAA implementation designed following the Control ad libitum philosophy proved to be capable of dynamic team formation and extremely robust against both hardware and software failure; and, due to the modularity of the system there is significant potential for reuse of assets and future extensibility. One future goal is to make the source code publically available and establish a forum for the development and exchange of new agents.

Keywords: robot teams
control system architecture
distributed
heterogeneous
failure recovery
SLAM
hardware-in-the-loop
Advisor: Emami, Mohammad Reza
To Cue or Not to Cue: Beacons and Landmarks in Object-displacement Tasks

Two experiments examined the role of various cues on children’s performance in a well-known object-displacement task. In this task, children observed a toy rolling down a ramp whose trajectory was occluded by an opaque screen with doors. A barrier was placed along the ramp, behind one of the doors, to stop the toy. The top portion of the barrier was visible above the screen. To search successfully, children had to retrieve the hidden toy by opening the correct door. Previous work had found that the barrier was an ineffective cue among children less than three years of age. According to a landmark-based account, this was because the barrier was only an indirect cue to object location. If a cue directly marked the location, then it would be more likely attended and utilized. This model underscores the spatial relation between cue and the target. Other cue properties are important in so far that they modify this spatial relation. In Experiment 1, a cue’s distance from the target object was manipulated (i.e., short vs. long), but the location marked by the cue was kept constant (i.e., correct door was directly below). The search performances of 24- and 30-month old children were compared under no cue, short-cue/short-door, and long-cue/long-door conditions. Both age groups performed equally well under both cued conditions. In Experiment 2, a cue’s movement (i.e., coincident with the car vs. not coincident with the car) down the ramp was manipulated. The performance of 24- and 30-month old children were compared under attached-direct cue and unattached-direct cue conditions. Both age groups performed well under both conditions. Collectively, the results provide support for the landmark-based account. The spatial relation between cue and target underlies toddlers’ search. Properties of the cue matter to the extent that they impact how well the cue marks its target.

Keywords: object-displacement task
landmark
beacon
cue use
toddler search
Advisor: Schmuckler, Mark
New Insights into the Evolutionary Mantenance of Male Mate Choice Behaviour using the Western Black Widow Spider, Latrodectus hesperus

Mate choice among males is relatively understudied, despite recent evidence supporting its ubiquity. Theory predicts male mate choice in response to variation in female quality, and male mating strategies that limit polygyny. However empirical research investigating these connections, particularly under natural conditions, is generally lacking. Using the Western black widow spider, Latrodectus hesperus, I investigated male mate choice, male investment, and the advantage of mating with females that differ in their potential to deliver fitness benefits to males via higher fecundity and/or reduced risk of sperm competition. Males were found to be preferentially attracted to larger, high-diet virgin females over females that were smaller due to a lower diet, or having been previously mated, or both. Through a three-year field study on females I found that males likely benefit from selectivity, as smaller, low-diet females often failed to deposit any egg sacs throughout the breeding season, likely due to their shortened web-site tenure and/or lack of bodily resources. I investigated the costs and benefits to male genital breakage in L. hesperus, a strategy typically assumed to result in male sterility while providing paternity protection. I found that genital mutilation in L. hesperus did not cause sterility and that males were capable of inseminating multiple females, likely because of the comparatively low amount of genital damage and the likelihood of the efficient placement of genital fragments. Evidence from double mating trials supported the efficacy of broken genital fragments as plugs, but first male sperm precedence was often maintained in cases where male genital breakage failed or fragments were positioned incorrectly, which occurred frequently. Together, these laboratory and field experiments contribute to a more complete view of mate choice.

Keywords: male mate choice
genital mutilation
mating plugs
spiders
natural populations
sexual selection
Advisor: Andrade, Maydianne
Interpreting Variability through Multiple Methodologies: The Interplay of Form and Function in Epipalaeolithic Microliths

The reason and significance of variation in material culture is one of the most fundamental debates in archaeological studies. These debates factor strongly into Levantine Epipalaeolithic research, where the morphological variability of microlithic tools has been interpreted to represent distinct cultural or ethnic communities. This dissertation addresses microlith variability during the Middle Epipalaeolithic (≈17,500 – 14,600 cal BP) through the analysis of lithic assemblages from Wadi Mataha, ‘Uyun al-Hammâm, and Kharaneh IV (Jordan). Although regionally disparate, the lithic assemblages are characterized by the same geometric microlith type: the trapeze-rectangle. The integration of typological, technological, morphometric, and use-wear analyses allows for the subtleties in material culture to be explored among these sites. In addition to these analyses, new methods for use-wear quantification are presented. This dissertation sets out to test several hypotheses in regards to the microlith assemblages: 1) microliths will have overlapping functions, indicating that function does not drive form; and 2) microliths will show differences in technological style. These hypotheses relate back to current debates in Epipalaeolithic research about the nature of microlith variability. Is variation in microlith morphology the product of different technological sequences of production or microlith function? Or is variability the result of different cultural practices? This material culture variability is explored through the lens of the chaîne opératoire, where I advocate for the inclusion of functional analysis into our study of lithic assemblages. Through the integration of multiple methods, I suggest there is not a direct correlation between microlith form and function. Instead, the variability we witness in microliths during the Middle Epipalaeolithic is the result of local expressions within different communities.

Keywords: lithic analysis
Epipalaeolithic
Advisor: Chazan, Michael
Considerations of Identity in Teachers' Attitudes toward Teaching Controversial Issues under Conditions of Globalization: A Critical Democratic Perspective from Canada

Controversy, as a vital principle of democracy, plays a central role in education for critical democratic global citizenship. Controversial issues, however, raise pedagogical challenges for teachers in that they are not only explicitly political, but also potentially threatening to the reproduction of status quo ideals and embedded national narratives – themselves keystones of citizenship education. The findings from this dissertation study report survey data on teachers’ attitudes toward teaching controversial issues from 202 Canadian teachers, as well as findings from interviews conducted with 16 Alberta teachers about how their multiple identities, and those of their students, intersect with their attitudes toward teaching controversial issues. The findings are discussed against indicators of critical democratic global citizenship education (CDGCE) which I advance in the thesis following from my investigation into the relationship between critical theory of a) democracy, b) globalization, and c) education. I engage the findings through the lens of critique and possibility and the reproduction and interruption of hegemonic discourse. Read through this lens, I found that hegemonic discourses of neutrality and universalism are being both reproduced and interrupted in complex ways that do affirm, but mostly refute, the promise of education for deepening democracy under conditions of globalization. Discourses of neutrality and universalism are being reproduced through insidious practices that affirm difference-blind and blank slate ideals and these need responding to. These have implications for how students in Canadian classrooms may be being prepared for critical democratic global citizenship education. Despite the misguided emphasis on the danger of teachers’ expressing extreme views in dominant discourses of education that question the place of controversial issues in school, I argue that the greater threat to deepening democracy is not teachers who express extreme views; it is curriculum and teachers who do not question familiar ones. In turn, I call for critical discursive and reflexive practices for teaching and learning with controversial issues that foreground identity, difference, and feelings as explicit material for learning. Finally, I delineate specific recommendations that are crucial responses for realizing the promise of education for deepening democracy under conditions of globalization.

Keywords: Teaching Controversial Issues
Canada
Critical Democratic Global Citizenship
Advisor: Portelli, John P.
Urban Greenspace, Civil Society and Science: The Creation and Management of the Rouge Park, Ontario, Canada.

Earth is becoming more urban. As the human population continues the current trend of migrating towards urbanized regions, the pressures to develop urban greenspaces will inevitably increase. Greenspaces play a critical role in urban livability for both human and non-human beings. This research examines the creation and management of the Rouge Park (Ontario, Canada), which is a large greenspace approximately 46 km2 located in the eastern portion of the Greater Toronto Area. The output of this research consists of three parts. The first provides an identification of the relevant actors, and a detailed chronology of the social and political events that led to the establishment of the Rouge Park. The second section explores the competing narratives of science, conservation, and development that were fundamental in shaping the protected area that we see today. The final section examines the governance and administration of the Rouge Park, and investigates the activities and involvement of civil society actors working in its day-to-day management. Using qualitative methods, I demonstrate that science and scientific expertise can be powerful tools of legitimization for civil society actors. In particular, I examine the benefits and pitfalls of placing ecologically-based rationalizations at the forefront of conservation policy deliberations. Furthermore, I show that despite shortcomings in the governance structure of the park, the current arrangement has provided civil society actors with increased opportunities to shape their community. My results show that a locally grounded nature conservation movement can serve as a powerful motivating force for citizens to enact long-term environmental planning initiatives.

Keywords: Rouge Park
civil society
Ontario
Canada
greenspace
conservation
Scarborough
Toronto
resource management
geography
GTA
Greater Toronto Area
Rouge River
national park
watershed
park
urban
livability
growth
science
nature
society
Parks Canada
Little Rouge Creek
Advisor: Andre, Sorensen
Biliteracy Development in Chinese and English: The Roles of Phonological Awareness, Morphological Awareness, and Orthographic Processing in Word-level Reading and Vocabulary Acquisition

This thesis examined the role of metalinguistic skills in concurrent and subsequent word-level reading and oral vocabulary among Chinese-English bilingual children who learned Chinese as their heritage language and English as their societal language. While previous studies on biliteracy development among this group of children have mostly focused on one of the two languages, this thesis gave equal emphasis to both languages. The research had two general purposes: 1) to investigate the role of phonological awareness, morphological awareness and orthographic processing in predicting word-level reading and oral vocabulary in Chinese and English concurrently and longitudinally; and 2) to examine the cross-linguistic role of phonological and morphological awareness to word-level reading and vocabulary, concurrently and longitudinally, between Chinese and English. These goals were explored through two interrelated studies, using path analyses. The participants included 91 Chinese-English bilingual children, recruited from kindergarten and Grade 1 Chinese heritage language classes in Canada. They were tested twice, one year apart, on a battery of cognitive and literacy measures in Chinese and English. Findings of Study 1 on within-language relationships indicated that, for word-level reading, all three metalinguistic skills were independent concurrent predictors in English, whereas only morphological awareness was predictive in Chinese. For oral vocabulary, morphological awareness was the only concurrent predictor in both languages. The longitudinal contributions of these metalinguistic skills were mostly mediated through the auto-regressors of the literacy outcomes. Findings of Study 2 on between-language relationships demonstrated that Chinese phonological awareness directly contributed to concurrent and subsequent English word reading beyond the effect of concurrent English phonological awareness. Yet, Chinese morphological awareness indirectly predicted concurrent and subsequent English oral vocabulary through concurrent English morphological awareness. Similarly, English morphological awareness only indirectly predicted concurrent and subsequent Chinese oral vocabulary. These findings suggest that different metalinguistic skills are required for literacy development in Chinese and English. Moreover, metalinguistic skills transfer to literacy, even across two typologically distant languages, but the transfer patterns of phonological and morphological awareness to different literacy skills vary considerably. These results are discussed in light of current reading and transfer models as well as linguistic contexts of biliteracy acquisition.

Keywords: reading development
biliteracy development
phonological awareness
morphological awareness
orthographic processing
Chinese reading
English reading
word reading
vocabulary
Advisor: Chen, Xi