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The interpersonal mechanisms of prenatal couple conflict dynamics
No full textAccording to Kluwer’s (2010) transition to parenthood model, attachment insecurity (attachment avoidance and anxiety) is a prenatal risk factor that can affect the ways couples manage conflict. However, the specific mechanisms that link attachment to conflict have not been elucidated. This thesis was the first to test emotional flooding, a type of interpersonal emotion dysregulation, as a mediator for the relationship between attachment insecurity and prenatal couple conflict behaviours. We also sought to understand the complex interplay between attachment and emotional flooding from a dyadic lens, examining how each partner’s attachment style might interact to predict heightened emotions during conflict. Cross-sectional data were collected from 98 couples who were expecting their first child. Data were analyzed using hierarchical linear modeling (Raudenbush et al., 1995), polynomial regression (PR) and response surface analysis (RSA; Shanock et al., 2010), and variations of actor partner interdependence models (APIM; Cook and Kenny, 2005). The interaction between avoidant men and anxious women predicted greater emotional flooding in men. Avoidance matching between partners also predicted greater flooding in women. Finally, flooding mediated the relationship between attachment anxiety and displays of distress in men and displays of hostility in women. Results support literature citing coercive dynamics and the emotional antecedents of aversive conflict behaviours. Limitations and clinical implications are also discussed.Graduate2025-05-1
Investigating the effects of ischemic stroke and diaschisis on connectomic presynaptic dendritic spine networks
Get PDFIschemic stroke is a life-threatening medical condition that can lead to dysfunction in brain regions both proximally and distally connected to the stroke site, a phenomenon known as “diaschisis”. Diaschisis can play an important role in recovery after stroke; however, the structural changes that occur at the level of neurons connected to the stroke site are not fully understood. Here, we performed confocal microscopy to visualize dendritic spines after a photothrombotic stroke in the primary somatosensory forelimb cortex (S1FL) of adult mice labeled with a retrograde adeno-associated virus (retro pAAV.CAG.GFP). This allowed for the visualization of presynaptic neurons directly connected to the infarct core in areas such as S1FL, motor cortex (MC), secondary somatosensory cortex (S2), and contralateral primary somatosensory forelimb cortex (Contra-S1FL). We observed a decrease in presynaptic spine density one week after stroke in superficial basilar dendrites within the peri-infarct region, which recovered by six weeks after stroke. An increase in dendritic spine density was also found six weeks after stroke within superficial primary apical dendrites in peri-infarct region, and within S2 in superficial primary and secondary apical dendrites as well as deep basilar dendrites. These results suggest that a retrograde degenerative signal may be localized to the peri-infarct region, whereas other factors may be playing a role in the widespread functional changes seen after stroke. The increase in dendritic spines seen in the peri-infarct and S2 regions six weeks after stroke may be playing an adaptive or compensatory role and aiding in recovery. Using a diaschisis model, these findings add novel information about neuronal structure proximal and distal to the infarct core, as well as elucidate potential degenerative and protective structural processes that may underly recovery after stroke.Graduat
Turnover and the retention of Indigenous executives in Indigenous organizations
Get PDFThis dissertation explores the phenomenon of executive turnover within Indigenous organizations in Canada, addressing a critical gap in the literature on Indigenous leadership and governance. Drawing on mixed methods, including surveys, interviews, and focus groups with Indigenous executives and organizational leaders, the study examines the demographic and professional characteristics of Indigenous executives, the causes and impacts of turnover, and strategies for retention. It reveals that executive turnover is driven by factors such as lateral violence, burnout, inadequate compensation, and governance challenges, significantly affecting organizational stability and performance. Findings emphasize the importance of culturally grounded retention strategies, fair compensation, and improved governance practices to support Indigenous leadership. By identifying actionable insights and theoretical propositions, this work contributes to the development of effective policies and practices to strengthen Indigenous governance and self-determination.Graduat
Exploring the “White Space” Between Leadership Training and Leadership Development Outcomes in the British Columbia Public Sector
Get PDFMany public sector employees take leadership training to become better leaders. However, employing the knowledge learned to produce real-life outcomes does not happen automatically. A developmental space exists between acquiring leadership knowledge and the desired leadership outcomes, also called the “white-space.” This study explored this space between post-training and desired leadership outcomes to investigate how British Columbia public sector employees draw from leadership training and other experiences to become better leaders. This study conducted in-depth one-hour-long interviews with 21 public sector employees in leadership roles across various organizations in B.C. The study addressed how individuals attempt to achieve multidimensional, zero, first, and second-order leadership learning outcomes, what individual, group, and organizational attributes affect the “white-space,” and how individuals learn from their daily life experiences to further their leadership.
Significant findings from the interviews include several ways in which B.C. public sector employees attempt to achieve multidimensional and/or zero, first, and second-order learning outcomes in the ‘white space’ post-leadership training. Individuals strive to attain these learning outcomes by supporting team members, nurturing others’ personal development, actively seeking avenues to augment leadership competencies, developing confidence, actively utilizing acquired skills and more. Findings also reveal the intrinsic motivators that drive public sector employees to pursue leadership development, such as the desire to grow and develop others, achieve tangible positive changes for the public, and foster positive relationships within their teams and organizations. Another key finding is the interplay between individual traits and interpersonal dynamics in shaping leader identity, particularly in the B.C. public sector context. While all participants viewed themselves as leaders, their perceptions of leadership and leader identity were influenced by their perception of their individual traits and who they are in relation to others.
Some crucial findings related to individual, team, and organizational attributes that impact the public sector leadership development post-training have also emerged. For example, positive team attributes were supervisory support and peer support, successful collaboration on team projects and ideas, and clarity in roles and responsibilities within the team. Some of the critical negative team factors included uncollaborative team environment, “bad leaders/supervisor,” and lack of social interactions. Concerning organizational attributes, being provided with a mentor or a coach, organizational commitment to leadership development, and opportunities to practice leadership skills were deemed vital, such as opportunities for jobs, new projects, and tasks critical for leadership development. Key findings related to the negative organizational attributes in the public sector included factors such as lack of follow-up discussions or further training, public sector’s hiring and talent management culture that discourages leadership development process and disconnect between training and real-life situations.
The last part of the study explored how participants develop leadership through daily life activities through participating in external committees or groups, coaching or volunteering, seeking out leadership training outside of work, reading books or listening to podcasts on leadership, and engaging in self-care activities.
Overall, the study demonstrates a complex interplay between these factors that ultimately shape B.C public sector employees’ leader identities and the leadership development process post-training and ends with practical recommendations for public sector leadership development, particularly in the Canadian context.Graduat
Modelling, experimental validation and evaluation of a parallel hybrid-electric propulsion system for small-scale UAVs
Get PDFThe aviation industry is currently focused on research and development of propulsion systems that produce less emissions, are more efficient, and can provide better range/endurance. Hybrid-electric systems have shown a promising potential in reducing emissions. Current battery technologies do not have the energy density required to meet most application requirements. While combustion technology has improved in efficiency over the decades; hybrid technology is required to take the next big step. In addition to the environmental benefits parallel hybrid technology provides other benefits such as operating mode variety, redundancy, and higher endurance.
In this thesis research, the primary goal is to model, evaluate and validate a mathematical model developed for a parallel hybrid-electric propulsion system. This model will be used in Model Based Design (MBD) to predict system performance, improve component selection, and optimize operation. For this thesis the modelling and design was completed for small-scale unmanned aerial vehicles (UAVs). A test bench was redesigned to handle the power produced by the combustion engine and electric motor (EM). For the experimental configuration a 50cc Corvid-50 combustion engine was used which produces 2.8kW at 7000RPM. This engine was combined with a SKP 6485 electric motor capable of 4.12kW continuously with a maximum speed of 8364RPM. Both power units are coupled together with a Mayr 500.301.0 type 4 electromagnetic clutch rated for 40Nm at 7000RPM. The propulsion system is connected to an electric dynamometer with programmable load capable of simulating any power profile. Telemetry for the system is collected through National Instruments hardware, electronic speed controller, and engine control unit.
During operation the test bench is able to operate in five different modes. Combustion and electric-only operation are capable by disabling the clutch for electric-only and running the electric motor at zero current for combustion. When running the system in a hybrid configuration there are three command modes: dual speed, throttle and speed, speed and current. Each of these command modes dictate which power unit governs speed while the other has direct torque control. Each of these hybrid modes provides the opportunity for regeneration and boost modes when requested. The test bench generates the experimental data required to model the propulsion system with accuracy. Using datasheets, unloaded runs, governing equations, and controller values component level models were created to complete initial simulations. The model and test iterative process repeated until the system level model responded well. To further develop the simulation model a virtual flight mission was created.
The test bench and Simulink model ran the virtual flight mission in combustion, electric, and hybrid modes. These different runs provided the data required to assess the model’s accuracy and demonstrate the difference between each propulsion technology. For these tests the simulation was able to predict speed and torque within a range of 1-12\% for steady-state operation between flight segments. The starting torque of the electric motor to initiate combustion was modelled to represent cold starts where the torque range was between 2-3Nm. Over the length of the fifteen-minute flight mission run the simulation predicted battery charge and fuel consumption within 5\%.
Energy density of each propulsion type was analyzed for the components used on the test bench. This showed that combustion power has the highest available energy density at 1.17MJ/kg; electric power is substantially lower at 0.35MJ/kg. The initial energy density of the hybrid system is 0.71MJ/kg but can be further optimized. By optimizing the energy masses for the hybrid-electric system an energy density equal to the combustion engine was accomplished with a 0.77kg mass reduction. This optimization process can be taken further by improving the command sequence of the system to incorporate regeneration, clutch disengagement, and throttle curve modification to reduce fuel flow.
The results of this research project created a simulation model and test bench capable of high-power flight tests. Both the model and test bench will continue to develop; further increasing the ability to design, optimize, and test parallel hybrid systems. This will provide the experience and knowledge to design, build, and integrate a power unit ready for flight testing.Graduat
Design and testing of a terahertz bandstop filter using varying radii split-ring resonators
Get PDFThe terahertz (THz) band which ranges from 0.1 THz to 10 THz has been relatively unexplored when compared to other frequency bands due to the unavailability of sources and detectors. However, continual advances in technology have made this frequency band more accessible and have attracted attention because of unique applications such as imaging, spectroscopy, communications, and physical defect detection. In many applications throughout the electromagnetic spectrum signal filtering is used to improve signal-to-noise ratios. One method to filter signals is using split-ring resonators (SRRs) that are made of nonmagnetic metals which respond to electromagnetic waves like a magnetic medium. SRRs at their resonant frequency create a magnetic dipole so that they can stop or pass electromagnetic waves. This property has made SRRs a commonplace element in the design of metamaterials (MTMs). This thesis does not focus on the investigation of MTM properties and characteristics (negative permittivity or negative permeability), but it does provide some of the relevant background and theory.
This thesis reports a proof-of-concept terahertz band-stop filter constructed from SRRs that has a center frequency of 1.06 THz and a -3 dB bandwidth of 0.36 THz. The design consists of nine SRRs of varying radii (3×13 µm, 3×14 µm, 3×15 µm) that are placed between the conductors of a coplanar stripline (CPS). The response of the filter is measured using a modified terahertz time-domain spectrometer and a reasonable agreement between simulation and experiment was found. This work demonstrates the viability of using varying-radii SRRs as discrete sub-wavelength filter elements for THz systems. In addition, the ABCD matrix approach was utilized to get the transmission response of the equivalent circuit. This filter was fabricated using gold on a thin Si3N4 substrate, and the simulated data are in good agreement with the experimental results.Graduat
Sentiment Analysis on IMDB Reviews leveraging Transfer Learning and Neural Network Models via Keras API
No full textThis project focuses on sentiment analysis using a pre-labeled IMDB dataset containing 50,000 movie reviews. Our approach leverages transfer learning and a pre-trained neural network from TensorFlow Hub, specifically the NNLM model, to streamline the preprocessing stage. The sentiment classification model is built using the Keras API with a Sequential architecture. To design the model, several attempts have been made to improve the performance and overall accuracy and the finalized model includes first layer of an embedding layer that utilizes the pre-trained NNLM embeddings, followed by a three-layer network consisting of dense layer, dropout layer and another dense layer for classification respectively. To compile the model, Adam optimizer and binary cross-entropy loss are defined while achieving an accuracy of almost 88%. In addition to this deep learning model, traditional sentiment analysis algorithms such as logistic regression, random forest, and SVM were also trained for comparison. Each attempt’s output is visualized and finally in conclusion part it is discussed which of the models output the desired performance considering two factors of efficiency and accuracy. The results highlight that by incorporating transfer learning and Keras API, the overall model complexity and computational cost were significantly reduced while maintaining competitive accuracy.Graduat
A protocol for developing and evaluating neural network-based surrogate models and its application to building energy prediction
Get PDFBecause of their low computational costs, surrogate models (SMs), also known as meta-models, have attracted attention as simplified approximations of detailed simulations. Besides conventional statistical approaches, machine-learning techniques, such as neural networks (NNs), have been used to develop surrogate models. However, surrogate models based on NNs are currently not developed in a consistent manner. The development process of the models is not adequately described in most studies. There may be some doubt regarding the abilities of such models due to a lack of documented validation. In order to address these issues, this paper presents a protocol for the systematic development of NN-based surrogate models and how the procedure should be reported and justified. The protocol covers the model development procedure sample generation, data processing, SM training and validation, how to report the implementation, and how to justify the modeling choices. The protocol is used to critically review the quality of NN-based SMs in the prediction of building energy consumption. Sixty-eight papers are reviewed, and details of the developed surrogate models are summarized. The reported developing procedures were evaluated using the criteria proposed in the protocol. The results show that the selection of the number of neurons is the best-implemented step with a justification, followed by the determination of model architecture, mostly justified in a discussion way. While greater focus should be given to sample dataset generation, especially input variables selection, considering independence check and clear report of model validation on training and test data. Also, data preprocessing is strongly recommended.This work was supported by the ReBuild Initiative NSERC Alliance grant.FacultyReviewe
Exploring Language Availability, Understandability, and Readability of Patient Medication Information
Get PDFMany Canadians use prescription medications and need information to support informed decision making as well as maximizing the benefits and minimizing potential harms of taking medications. Patient Medication Information (PMI)—the paper leaflets provided with prescriptions—helps disseminate information. However, the availability of PMI in a consumer’s preferred language and how it is written can impact its effectiveness. Thus, this study explored 1) the availability of PMI in English, French, and Mandarin and 2) the patient-centredness of PMI in terms of its understandability and readability. PMI was available in English from all five chosen pharmacies. However, only two pharmacies provided PMI in French, and none offered it in Mandarin. For the PMI obtained, the French PMI was easier to read and understand than the English PMI. There were differences within the English PMI depending on the pharmacy source, demonstrating three areas of improvement that limit PMI’s value to the public. First, PMI should be standardized so that people receive the same information regardless of the pharmacy they use. Second, the content of PMI could be improved to make it easier for people to read and understand. Third, PMI in a person’s preferred language should be easy to obtain from pharmacies.Jamie Cassels Undergraduate Research Awards (JCURA)UndergraduateReviewe
Non-standard finite difference and Vieta-Lucas orthogonal polynomials for the multi-space fractional-order coupled Korteweg-de Vries equation
Get PDFThis paper focuses on examining numerical solutions for fractional-order models within the context of the coupled multi-space Korteweg-de Vries problem (CMSKDV). Different types of kernels, including Liouville-Caputo fractional derivative, as well as Caputo-Fabrizio and Atangana-Baleanu fractional derivatives, are utilized in the examination. For this purpose, the nonstandard finite difference method and spectral collocation method with the properties of the Shifted Vieta-Lucas orthogonal polynomials are employed for converting these models into a system of algebraic equations. The Newton-Raphson technique is then applied to solve these algebraic equations. Since there is no exact solution for non-integer order, we use the absolute two-step error to verify the accuracy of the proposed numerical results.This research was funded by the Deanship of Scientific Research at Najran University under grant number (NU/DRP/SERC/12/16).FacultyReviewe