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Designing the playscape: an interactive learning resource center that encourages creative learning
No full textHuman civilization and society have grown exponentially over the last millennia through the help of innovation and technology. What, then, propels innovation and technology? Throughout history, humans have used their imagination and creativity to make new things, tools, devices, and buildings to make life easier and advance civilization. The knowledge to create and use these tools is taught to the next generation through educational services and facilities such as learning resource centers. At its core, a learning resource center is usually a library that provides and encourages audiovisual aids, other tools, and books to support the educational system. The research in this practicum aims to define the connection between creativity and education through play and to study the typologies of learning resource centers/libraries and playful areas/third places such as playgrounds. As society is ever-evolving and growing, so too must its inhabitants. While the education system can teach people how to use sophisticated tools, the system could be improved with more opportunities to teach it creatively. Thus, this practicum aims to introduce a dynamic approach to designing learning resource centers by creating playful environments. The research focuses on exploring the concepts of play, interactive design, and maker spaces and using them to iterate a new design typology. This practicum will design an interactive learning resource center as a hub for individuals seeking growth, collaboration and learning through play. The project aims to contribute to the design industry by studying the outcome of combining two distinct typologies: learning resource centers (LRC) and playful areas, such as playgrounds. The research will provide various techniques and tools to create environments that promote learning through play.May 202
Publisher Correction to: Exploring patient and caregiver perceptions of the meaning of the patient partner role: a qualitative study
No full textPerformance of hot-mix asphalt mixtures for a balanced mix design
No full textSeveral transportation agencies in Canada are currently relying on volumetric properties of asphalt mixtures to accept or reject the final mix design. The existence of various pavement defects on Canadian roads indicates that volumetric mix design procedure alone does not guarantee adequate long-term pavement performance. Therefore, transportation agencies in Manitoba are finding ways to increase durability of their asphalt mixtures to accomplish a road network that is more sustainable, safer, and more economical. The balanced mix design (BMD) approach integrates two or more performance test criteria into mix design and acceptance to produce asphalt mixtures that are resistant to cracking and permanent deformation. The objective of this study is to assess cracking and rutting performance of plant-produced asphalt mixtures as well as fractionated reclaimed asphalt pavement (RAP) mixtures to validate current volumetric mix design methods and investigate ways to optimize mix performance for moving towards a BMD. Fractionated RAP mixtures were produced in the laboratory and plant-produced mixtures were collected from different pavement construction projects to prepare specimens for cracking and rutting evaluation. Cracking performance was determined using the Illinois flexibility index test and rutting performance was determined using the Hamburg wheel-tracking test. Results showed that polymer-modified binders, recycled materials, and reduction of nominal maximum aggregate size contributed to better rutting performance. In addition, RAP fractionation technology showed a promising effort in making asphalt mixtures move towards a BMD. Conversely, limestone aggregates and recycled asphalt shingles reduced cracking resistance and did not lead to a BMD.May 202
Experimental investigation and numerical modelling of under cover ice transport and hanging dam formation processes
No full textUnder cover ice transport and hanging dam formation are river ice processes that have a significant impact on hydraulics of an ice covered river during the winter. A thick ice accumulation from a hanging dam can cause the water level to rise imposing flooding to nearby communities, and hydropower generation during the winter is often negatively impacted by hanging dams. Under cover ice transport and hanging dam formation processes are not yet well understood due to difficulties associated with obtaining field data and lack of numerical modelling efforts. This research investigates under cover ice transport and hanging dam formation processes using laboratory experiments and numerical modelling. Under cover ice transport laboratory experiments were conducted to further develop a cover load transport formula describing the relationship between dimensionless transport rate and dimensionless flow strength under equilibrium conditions and this formula is known to be the only cover load formula that is developed exclusively using simulated ice that has similar physical properties to ice in a natural river. The effect of approach Froude number in the river and the incoming ice supply rate on hanging dam formation was analyzed using a series of experiments in a scaled down physical model. This is the first study of its kind that presents the relationship between the approach Froude number and the incoming ice supply rate on hanging dam formation and evolution, contributing to improving our understanding of these processes. The current model formulation for under cover transport processes and hanging dam formation in the CRISSP2D numerical model was evaluated and the laboratory developed cover load transport formula was incorporated in the model to improve the model in this application.February 202
Modular multilevel converters with partially integrated battery energy storage
No full textThis thesis investigates Modular Multilevel Converters (MMCs) with partially integrated Battery Energy Storage Systems (BESS), where only a subset of sub-modules (SMs) are equipped with battery energy storage via bidirectional boost converters. The primary goal of incorporating BESS is to provide inertial and frequency support to the grid. These converters are typically studied using Electromagnetic Transient (EMT) simulations. A continuous-time model of the MMC-BESS is developed based on the state-space equations of the converter. The proposed model enhances computational efficiency in two key ways: (i) it significantly reduces the number of nodes in the conventional switching model, thereby shrinking the size of its admittance matrix, and (ii) it avoids computationally expensive re-triangularization of the admittance matrix during normal operation, restricting it to rare instances of converter blocking. This method results in substantial reductions in the simulation time of MMC circuits, making it particularly useful for studies requiring repetitive simulations. The computational efficiency and accuracy of the proposed model are validated by comparing its implementation in the PSCAD/EMTDC simulator against conventional detailed switching models and experimental measurements from a single-phase scaled-down laboratory setup. The Peak Current Mode (PCM) control strategy is used to manage the DC-DC converters integrating the batteries with the MMC. PCM provides a protective layer that limits the current through the battery and DC-DC converters' switches. An Averaged Value Model (AVM) of the MMC-BESS, along with its per-unit representation, is also derived. The AVM is beneficial for low-frequency studies, such as upstream control design and SM capacitor sizing. Finally, the proposed topology and its model are used to explore replacing Manitoba's outdated Bipole I HVDC system with a VSC-HVDC system featuring MMC and MMC-BESS at the rectifier and inverter terminals, respectively. The study aims to stabilize and maintain system frequency while eliminating synchronous condensers and AC line filters.February 202
Singular solutions of a Hénon equation involving nonlinear gradient terms
No full textThis thesis explores a class of nonlinear elliptic partial differential equations known as Hénon-type equations, employed in various scientific domains including physics, biology, and applied mathematics. These equations are particularly useful in modeling pattern formation, reaction-diffusion processes, and population dynamics. The central focus is on determining solutions to equations of the form:
\noindent
We investigate the existence of positive singular solutions for Hénon-type equations involving nonlinear gradient terms. Specifically, we study equations of the form:
where , , is the unit ball centered at the origin in , and is a Hölder continuous function with . We prove the existence of positive singular solutions under various parameters under various conditions.
Moreover, we extend the analysis to exterior domains in , exploring the existence of positive classical solutions to equations of the form:
where is an exterior domain that does not contain the origin in its closure.
\noindent
We also consider the case where the solution has two singular points in . In particular, we consider:
where is a bounded domain in \IR^N with .
\noindent
This work contributes to understanding singular solutions in H\'enon-type equations, offering new insights into their behavior across various domains and parameter ranges.October 202
Impact of sex work and behavior on the immunological milieu of young female sex workers in Mombasa, Kenya.
No full textHIV disproportionately affects adolescent girls and young women in Sub-saharan Africa and having a diverse microbiome has been associated with an increased risk of HIV acquisition. Among African women studies have shown that most women harbour diverse microbiome groups, and this is coupled by high recurrence rates even after successful treatment of BV. We hypothesize that sexual intercourse and sex work has a negative impact on the immunological and microbial milleu of the female genital tract and is associated with increased sexually transmitted infection risk in adolescent and young girls from Mombasa.
Adolescent girls and young women were recruited from hotspot in Mombasa, Kenya and they self-triaged into 3 distinct groups using a triage questionnaire: Non-sex worker group, transactional group and female sex worker group. Cervicovaginal lavage and urine were collected from the study participants. The CVL sample was processed into a supernatant which was used to measure cytokines and soft cup pellet which was used to for microbiome sequencing and gene expression assays. The urine was used for qPCR of sexually transmitted infections.
In the first sub study we analysed microbiome data for 168 samples and found that molecular-BV was common among the participants, and it was highly correlated with cytokines associated with increased risk of HIV acquisition (chapter 4). We further assessed cytokine receptor expression of the samples above and found that most receptors were downregulated especially those that contained diverse microbiome (chapter 5). In this chapter we further assessed whether there was a correlation between barrier marker E-cadherin and, receptors and epidemiological variables and found that participants in the female sex worker and transactional groups have lower levels of E-cadherin (p=0.015). A negative correlation was also observed between E-cadherin and some of the receptors; IL10RA (p=0.027, R= -0.259*), IL1RAP (p=0.046, R= -0.234*), GMCSFRA (p=0.023, R= -0.267*), IFNYR2 (p=0.013, R= -0.291*).
In this cohort we found an interestingly low prevalence of sexually transmitted infections (Chapter 6) specifically Neisseria gonorrhea infections 0.5% (5). The most common STIs were Mycoplasma hominis 14.9% (114) and Ureaplasma urealyticum 18.9% (183) which are not classified as real STIs. When we further assessed whether having an STI or the combination of an STI and diverse microbiome has an impact on immune markers we found that the latter is associated with decreased expression of some receptors; CXCR1(p=0.012), GMCSFRA(p=0.045), IL2Rg (p=0.013), IFNyR2 (p=0.050) and CXCR3 (p=0.017).
In conclusion, this study shows the importance of assessing behavior in studies that are focused in understanding the immunological and microbiological factors that contribute to the disparities of HIV infection especially among adolescent girls and young women.October 202
Upper vs whole body cooling during exercise with thermal protective clothing in the heat
No full textIntroduction: Firefighters operating in hot environments face challenges from protective garments that restrict heat dissipation, resulting in increased core temperature, thermal discomfort, and performance decline. Cooling vests represent a viable solution. The study aim was to compare effectiveness of the same amount of cooling power to the upper body (UB) or whole body (WB) in alleviating thermoregulatory and physiological stress, enhancing cognitive function, and reducing ratings of thermal discomfort and exertion, during 60 min of exercise in a hot environment (40°C, 40% relative humidity) while wearing firefighter turnout gear. Methods: Eight healthy individuals (27.5±3 y) participated in three conditions with either no cooling (Control) or active cooling with a liquid perfused shirt (UB cooling), or with a liquid perfused shirt and pants (WB cooling). In each trial, participants performed three sets of 15 min of stepping (20 steps/min) and 5 min of rest. Results: Both cooling strategies were beneficial compared to having no cooling at all. Participants could only complete two exercise bouts during Control, but they completed all three bouts with active cooling. WB cooling provided an advantage over UB cooling for core and skin temperature, and thermal comfort and sensation. The advantage in minimizing the increase in core temperature was only evident during the third exercise bout. Conclusion: Active cooling is advantageous under these conditions. WB cooling provided some benefits versus UB cooling during heavy intensity exercise; however, it is uncertain whether these benefits would be observed during light-to-moderate exercise, which more likely reflects an actual firefighting scenario.May 202
Profitability of growth-enhancing technologies in Canadian feeder cattle production
No full textThe Canadian beef industry is experiencing heightened domestic and global demand; however, it is constantly challenged by the extremely narrow profit margins. In an effort to enhance efficiency, the cattle feeding industry has adopted the use of growth-enhancing technologies (GETs), which has resulted in cattle getting to finished weights more quickly. This study focuses on three types of technologies in the feedlot phase of the beef supply chain, including a trenbolone acetate + estradiol (TBA) implant, melengestrol acetate (MGA) feed additive and ractopamine hydrochloride (RAC) feed additive. Previous research has found positive impacts of GETs on animal performance and environmental sustainability; however, economic dimensions have not been as thoroughly explored. Accordingly, this thesis is the first attempt to use recent Canadian feedlot data to determine economic gains from GET adoption by feedlots. The objective of the research conducted for this thesis is to determine the relative profitability of cattle feeding in Canada using GET (conventional) versus non-GET (non-conventional) systems. Supporting objectives are to evaluate and compare measures of animal performance of the treatment groups; and determine the efficiency of conventional and non-conventional systems by estimating the probability distribution of risk. To achieve these objectives, data from a four-year animal trial at the Agriculture and Agri-food Lethbridge Research and Development Center are used, along with supporting price data from CanFax Research Services and Statistics Canada within an enterprise budgeting framework with accompanying risk analysis. Results from the partial enterprise budget indicate that the feeding system which employed TBA has the highest net returns for both heifers and steers; however, results from the risk analysis differ. Using stochastic dominance, feed additives were discovered to be second-degree stochastic dominant for their respective sex class. Further investigation confirms that a production system providing an RAC feed additive to steers is the least likely to generate a negative net return; and likewise for heifers receiving a TBA implant.October 202
From mine-face to micron-scale investigation of the Cretaceous McMurray Formation at Kearl Mine, northeastern Alberta, Canada
No full textRiver meander-belt morphodynamics are critical to understanding fluvial sedimentology, however, the process-to-product relationships are highly complex. To improve understanding of meander belt heterogeneity and depositional processes this thesis investigates the Lower Cretaceous McMurray Formation at Kearl mine, northeastern Alberta. The research objectives are to i) utilize extensive mine-face exposures by integrating them with related borehole data to reconstruct the local paleoenvironment, ultimately interpreting the paleochannel morphodynamic evolution through time; and ii) investigate fluvial mudstone microstructure of point-bar mudstones from Kearl mine using scanning electron microscopy (SEM).
The area of interest at Kearl mine is a 1.9 x 1.1 km area where mine-faces were excavated while on-site geologists documented notable geologic features. A focus of the study is the atypical channel-belt deposit trends observed in one of the documented point bars. The atypical point-bar deposits comprise inclined heterolithic stratification (IHS) that was interspersed with mudstone clast breccias and mudstone-lined trough cross-bedded sandstone. The deposits were localized in a segment of the point bar that did not conform to upward- nor downstream-fining trends in typical point-bar models. To better understand these peculiar deposits, this research produces and utilizes a planform reconstruction to investigate the fluvial processes that occurred during the atypical deposition, noting that the upstream cutbank material was mudstone-rich and may have influenced the atypical point-bar heterogeneity. Furthermore, a mudstone sampled downstream from the atypical deposits is analyzed with SEM to observe microstructure characteristics, which reveals evidence of sub-mm-sized mudstone aggregates. The presence of these micron-scale mudstone aggregates implies that a broader range of hydrodynamic conditions should be considered for fluvial mudstone deposition, particularly the mudstone component of point-bar IHS.October 202