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Study of the Cellular Detonation Dynamics at the Sub-Cell and Macro Scales
No full textThis thesis, presented as a series of articles, aims to provide a deeper understanding of how small-scale dynamics, i.e., the cellular structure of the reaction zone, influence large-scale dynamics, i.e., the shape and dynamics of the wave globally, and to develop a rational model for predicting the detonation dynamics at these large scales. Previous studies on detonation propagation in curved channels and suddenly enlarging area have shown that, while the detonation front remains cellular, the geometry induces a global curvature that is integrated over many cells. The resulting detonation dynamics can be effectively described by a speed-curvature ( – ) relationship, where non-steady effects are negligible at this scale. However, both curvature and non-steady effects are very important when investigating the detonation behaviour at the cellular level. This thesis aims to elucidate these effects through experimental analyses and modelling of detonation dynamics and behaviour.
The first article, presented in Chapter 2, investigates the evolution of a multi-cellular, irregular detonation structure, predicting its behaviour based on the global response of the detonation front to geometric influences. We introduce new experiments on detonation diffraction in a 2D channel, focusing on the highly irregular cellular structure of detonations in stoichiometric mixtures of ethylene, ethane, and methane with oxygen as the oxidizer. The critical conditions for detonation diffraction and the critical channel height for each mixture are determined experimentally. Critical curvature data obtained from single-headed detonation experiments conducted in a separate study were found to provide a good prediction of critical diffraction in detonation diffraction experiments. This finding supports the view that the concept based on the ( – ) relationship is meaningful in predicting critical diffraction of irregular structure detonations. Chapter 3 examines whether incorporating the global effect of curvature is a relevant approach to understanding the weakly transient phenomenon of detonation initiation. A novel experimental technique is proposed to isolate detonation formation from the reflection of two decaying shocks. The test gases include a regular cellular structure mixture of 2H₂/O₂/2Ar and a highly irregular cellular structure of CH₄/2O₂. Through these experiments, we identified three distinct regimes: detonation formation, a Mach shock followed by a flame, and a case where no ignition occurs behind the Mach shock. The transition between detonation formation and ignition was found to follow the critical curvature theory of quasi-steady curved detonations closely. Moreover, the boundary between re-ignition and no re-ignition was accurately predicted by the critical decay rate theory.
In Chapter 4, we study the propagation of detonation waves in narrow channels which are subjected to boundary layer losses. The effect of boundary layer losses appears as the lateral divergence of the flow due to the increase in boundary layer displacement thickness. Two highly regular cellular structure mixtures of 2H₂/O₂/7Ar and 2H₂/O₂/7He are employed as test gases. Both diluents, argon and helium, have identical kinetics, Mach number, and specific heat ratio; however, their transport properties differ. The experiments showed variations in velocity deficits and cell sizes, despite being designed to maintain a constant induction zone length across the mixtures. These differences were explained by modelling the impact of global lateral flow divergence caused by boundary layer losses. Therefore, it appears that the large-scale dynamics are controlled by the long reaction zone thickness and are decoupled from the rapid dynamics of the front.
In Chapter 5, we use the same experimental setup—a narrow channel—to investigate the hydrodynamic thickness of detonations in the regular mixture of 2H₂/O₂/7Ar and irregular mixture of CH₄/2O₂ cellular structures. We experimentally measure the mean pressure evolution within a detonation cell as well as the pressure changes resulting from the head-on reflection of the detonation wave. Our experiments show that, on a global scale, the hydrodynamic thickness corresponds to the length of one cell in both mixtures. Furthermore, we confirm that the overall pressure evolution of the detonation wave and its reflection can be accurately reconstructed using the one-dimensional ZND model for the regular mixture. For the irregular mixture, we introduce a simplified one-step model tailored to the global structure of the reaction zone. Building on the work presented in Chapter 4, we further confirm that in narrow channel experiments, the large-scale dynamics, in mixtures characterized by the extended reaction zone, can be decoupled from the fast dynamics of the front. These findings suggest that a physically accurate model of the reaction zone is adequate to capture the detonation dynamics.
In Chapter 6, we take the next step toward developing a sub-cellular model within a cell. While transient effects are crucial within a detonation cell, the onset of the reaction occurs much faster initially than its decay rate. Therefore, this work focuses on predicting detonation dynamics within a single cell, specifically determining the shock strength at the start of the cell based on its strength at the end. To achieve this, we reformulate the triple-point reflection model, assuming that the Mach shock is reactive. The objective is to predict the strength of the lead shock following the triple-point collision. The model’s predictions are then compared to experimental data from detonations propagating in narrow channels with an enlarged cell structure, with high-speed schlieren imaging capturing the reflection dynamics. Despite experimental uncertainties, the model demonstrates a strong agreement with the observed results
The effects of deprivation, age, and regional differences in COVID-19 mortality from 2020 to 2022: a retrospective analysis of public provincial data
No full textAbstract Background Coronavirus disease (COVID-19) quickly spread around the world after its initial identification in Wuhan, China in 2019 and became a global public health crisis. COVID-19 related hospitalizations and deaths as important disease outcomes have been investigated by many studies while less attention has been given to the relationship between these two outcomes at a public health unit level. In this study, we aim to establish the relationship of counts of deaths and hospitalizations caused by COVID-19 over time across 34 public health units in Ontario, Canada, taking demographic, geographic, socio-economic, and vaccination variables into account. Methods We analyzed daily data of the 34 health units in Ontario between March 1, 2020 and June 30, 2022. Associations between numbers of COVID-19 related deaths and hospitalizations were explored over three subperiods according to the availability of vaccines and the dominance of the Omicron variant in Ontario. A generalized additive model (GAM) was fit in each subperiod. Heterogeneity across public health units was formulated via a random intercept in each of the models. Results Mean daily COVID-19 deaths increased quickly as daily hospitalizations increased, particularly when daily hospitalizations were less than 20. In all the subperiods, mean daily deaths of a public health unit was significantly associated with its population size and the proportion of confirmed cases in subjects over 60 years old. The proportion of fully vaccinated (2 doses of primary series) people in the 60 + age group was a significant factor after the availability of the COVID-19 vaccines. The deprivation index, a measure of poverty, had a significantly positive effect on COVID-19 mortality after the dominance of the Omicron variant in Ontario. Quantification of these effects was provided, including effects related to public health units. Conclusions The differences in COVID-19 mortality across health units decreased over time, after adjustment for other covariates. In the last subperiod when most public health protections were released and the Omicron variant dominated, the least advantaged group might suffer higher COVID-19 mortality. Interventions such as paid sick days and cleaner indoor air should be made available to counter lifting of health protections
Of Receptors and Responses: Characterizing GPCR Signalling Pathways and Interactome Networks to Inform their Pharmacological Profiles
No full textG protein-coupled receptors (GPCRs) epitomize a preeminent class of drug targets, orchestrating a myriad of physiological processes. Notwithstanding their paramount biomedical importance, the advancement of GPCR-targeted drug discovery is impeded by the limitations of extant screening tools, which predominantly assess GPCR activation through agonist-induced G-protein and β-arrestin-2 activities. In this dissertation, we optimize and develop novel approaches to enhance the functional characterization of GPCRs and present non-canonical exemplars from the realm of GPCR-protein interactions.
We introduce Tango-Trio, a robust high-throughput cell-based platform that enables the parallel profiling of both basal and agonist-dependent activities of GPCRs. This platform captures the functional diversity of GPCRs, including β-arrestin-1/2 couplings, selectivities, and receptor internalization signatures. By constructing cumate-induced basal activation curves for approximately 200 receptors, including over 50 orphans, Tango-Trio provides a valuable tool for comprehensive GPCR screening and characterization.
Further, we develop the NbV5 tag system, an intracellular nanobody targeting the V5-tag, which enhances the study of protein-protein interactions (PPIs) in cellular assays. The smaller size of the V5-tag minimizes perturbations to protein stability and localization compared to larger functional moieties. This system is applicable in GPCR-based assays such as Bioluminescence Resonance Energy Transfer (BRET), NanoBiT, and Tango, and proves effective in live-cell imaging and microscopy, facilitating more accurate and versatile interrogation of GPCR signaling pathways.
Finally, we investigate the dynamic isoform-specific interactions between GPCRs and 14-3-3 proteins, a family of adaptor proteins that regulate various cellular processes, including signal transduction, cellular stress responses, apoptosis, and cell cycle progression. Utilizing stable reporter cell lines expressing all seven human 14-3-3 isoforms, we perform high-throughput agonist-based screening across approximately 100 non-orphan GPCR. Notably, we identify the neurokinin 3 receptor (NK3) receptor as a key candidate for in-depth study and demonstrate that different combinations of 14-3-3 isoform dimers modulate NK3 receptor activity, including surface expression and signaling pathways, thereby highlighting the intricate regulatory mechanisms of GPCR function.
Collectively, this work advances our understanding of GPCR signaling and PPIs in the proximal interactomes of GPCRs, offering new methodologies for drug discovery and providing insights into the sophisticated regulatory networks that underpin these receptors’ myriad functions
Ann Fenwick of Hornby: British Catholicism and the State in Hanoverian England
No full textIn eighteenth-century Britain, Roman Catholics were formally disabled by the restrictions imposed upon them by the penal laws. Under these laws, Catholics could not inherit land, dispense with their property as they wished, or obtain justice in the courts. However, the penal laws were not as rigid as they appeared in formal legislation. Ann Fenwick, a woman from Hornby, Lancashire, inherited her father’s estate at a young age and lived her life openly as a Catholic without facing any legal repercussions for her violations of these laws. However, when her husband died intestate, her brother-in-law, Thomas Fenwick, a lawyer and Member of Parliament for Westmorland from 1768-1774, took advantage of the disabilities imposed by the penal laws to deprive Ann of money she was owed. Despite this, Ann continued to live unabashedly as a Catholic, using what little money she had to finance the Catholic mission she began in her home. After her brother-in-law failed for years to pay her according to the annuity agreement the two had struck, Ann sued Thomas and received relief through a private Act of Parliament passed in the House of Lords. By investigating the life experiences of Ann Fenwick through previously underutilized archival material, including correspondence, financial ledgers, written prayers, legal petitions, and a private Act of Parliament, this thesis reveals a thriving Catholic community in Hanoverian England, a community that drew upon connections made in economic, religious, and familial spheres to live fruitful and faithful lives with limited fear of state persecution. The growing toleration from the landed Protestant elite towards Catholicism was born out of discussions of liberty and property. This interpretation challenges the traditional view of the English Catholic community in Hanoverian Britain as a group which was forced to act clandestinely to eke out a meagre subsistence
A Parallel Implementation of the Discontinuous-Galerkin-Hancock Method on Unstructured Meshes with Adaptive Mesh Refinement
No full textThe steady increase in computational power over the last generation gives rise to fields of research that use it, which is why Computational Fluid Dynamics (CFD) has been, and remains, a rapidly evolving field of research. Traditionally, the Navier-Stokes (NS) equations have been used almost exclusively to model viscous gas flows. More recently, the field of moment methods have emerged as an alternative. Moment methods are derived from the kinetic theory of gases. Because of this, they offer certain advantages over the NS model, such as an improved accuracy in describing rarefied gases or multiphase flow, where the microscopic scale can be more prominent. These moment methods are described by first-order hyperbolic partial differential equations (PDE) with stiff local relaxation source terms. The discontinuous-Galerkin (DG) methods, initially designed to solve first order hyperbolic balance laws, are of particular interest in the current study. The discontinuous-Galerkin-Hancock (DGH) method is of third-order accuracy, was designed specifically for the efficient solution of moment methods, and lends itself well to large-scale parallel computing. Once a scheme like DGH has been identified, it is always coupled with a tessellation of space. In a structured discretization, space is often split into quadrilaterals, which can be numbered in an orderly manner, such as would be considered intuitive or “structured”. Contrarily, an unstructured discretization splits space into polygons of theoretically any number of sides. This allows complex geometries to be more easily represented, and hence is more versatile. Given these meshes’ unstructured nature, their implementation becomes less straightforward. The current study outlines a paralellized implementation of the DGH scheme on unstructured meshes in two and three dimensions. An adaptive refinement algorithm was developed alongside this. The implementation allows the computational tasks to be spread amongst many processors, and its adaptive nature allows this implementation to tailor its mesh’s detail to the solution that is being computed in real-time. A multitude of different first-order PDEs in different contexts are solved in the current study. To begin with, a supersonic flow-past-bump case is investigated using the compressible Euler equations. This is done to showcase the adaptive refinement algorithm’s power, combined with the scheme’s ability to capture strong shocks. Next, the unstructured nature of the implementation is taken advantage of with complex geometries, such as for a multi-element airfoil, and for a room equipped with sound diffusion. The flow around the airfoil is modeled using the 10-moment Gaussian moment closure, to capture viscosity’s effects with a first-order hyperbolic model. Finally, the linear convection equations are used to verify the scheme’s order of accuracy on 2D and 3D meshes, and the Euler equations are used on a varying number of CPUs to demonstrate the implementation’s scalability on large clusters
The Spiritual Director in Orders of Monks: A Canonical Analysis
No full textSpiritual direction enjoys a prominent place within the monastic vision and ascetical discipline. Monks, however, have struggled to answer one simple question: Who is a monk’s spiritual director? Over the long development of universal and proper law and monastic customs, various answers have emerged sometimes emphasizing the superior’s spiritual paternity, at other times emphasizing the common good and discipline of the religious institute, and still at other times, especially in recent history, emphasizing the freedom of conscience as an application of the right to privacy. Since the Second Vatican Council has given religious a dual mandate for reform in Perfectœ caritatis to return to the sources and make suitable adaptations in the contemporary context, the canonical analysis of the spiritual director in orders of monks offers a tangible pattern of how the historical notion of the spiritual director can be adapted to the ius vigens without conflation of the fora and spiritual abuse.
This dissertation, therefore, purposes to analyze the canonical norms governing the spiritual director, to identify the resultant challenges in post-conciliar monasticism, and therefrom to offer a legal opinion of what might be done in orders of monks to address licitly these challenges in practice. Methodologically, this study commences with the historical evolution of the spiritual director from nascency in the desert experience and as promulgated in the monastic rules (chapter one) before considering the juridic treatment of the spiritual director in the 1917 and 1983 codifications (chapter two). Finally, the study considers the spiritual director post-codification in Church documents and monastic custom (chapter three) before surveying practical circumstances to offer a canonical appraisal and modest suggestions towards greater canonical observance (chapter four)
The revised Canadian Bleeding (CAN-BLEED) score for risk stratification of bleeding trauma patients: a mixed retrospective—prospective cohort study
No full textAbstract Background Traumatic hemorrhage is a significant cause of morbidity and mortality. There is considerable interest in risk stratification tools to aid with early activation of intervention pathways for bleeding patients. In this study, we refine the Canadian Bleeding (CAN-BLEED) score for the prediction of major interventions in bleeding trauma patients. Methods We conducted a mixed retrospective-prospective cohort study. We included a retrospective cohort from the CAN-BLEED derivation study, from September 2014 to September 2017. We also conducted a prospective cohort from May 2019 to August 2021 and included both datasets for refinement of the CAN-BLEED score. The primary outcome was major intervention, defined by a composite of massive transfusion, embolization, or surgery for hemostasis. Predictors were pre-specified based on previous validation work. We used a stepdown procedure and regression coefficients to create a clinical risk stratification score. We used bootstrap internal validation to assess optimism-corrected performance. Results We included 1368 patients in the overall cohort. Incidence of penetrating injury was 23% and median injury severity score was 17. The overall incidence of the need for major intervention was 17%. The revised score included 8 variables: systolic blood pressure, heart rate, lactate, penetrating mechanism, pelvic instability, Focused Abdominal Sonography for Trauma positive for free fluid, computed tomography positive for free fluid, or contrast extravasation. The C-statistic for the simplified score is 0.89. A score cut-off of less than 2 points yielded a 97% (94–98%) sensitivity in ruling out the need for major intervention. Conclusion The revised CAN-BLEED score offers a clinically intuitive and internally validated tool with excellent performance in identifying patients requiring major intervention for traumatic bleeding. Further efforts are required to evaluate its performance with an external validation
The Role of Tetrazinyl Radical Ligands in Lanthanide Metallocene Single-Molecule Magnets
No full textBeing at the forefront of new technological advancements in quantum information processing and spintronics, single-molecule magnets (SMMs) have greatly benefited from the incorporation of lanthanide (Ln) ions. Although mononuclear organometallic Ln-based SMMs have been the clear frontrunners in achieving high blocking temperatures and large energy barriers, the weak Ln···Ln magnetic interactions hinder the magnetic performance of polynuclear Ln-based SMMs. To this end, radical ligands with diffuse electron density can promote strong magnetic interactions with the Ln ions and potentially lead to strongly coupled, high-performing SMMs. The present dissertation focuses on exploring s-tetrazines as bridging ligands in lanthanocene complexes with a close emphasis on their magnetic properties.
In pursuit of tetrazinyl-bridged lanthanocene SMMs, the combination of highly delocalized 1,2,4,5-tetrazinyl radical anion (tz•–) with lanthanide metallocenes led to the isolation of a family of radical-bridged dinuclear lanthanocene complexes: [(Cp*2Ln)2(tz•–)(THF)2](BPh4) (Ln = Gd (1-Gd), Tb (1-Tb) and Dy (1-Dy); Cp* = pentamethylcyclopentadienyl; THF = tetrahydrofuran). Magnetic measurements and computational studies confirmed the very strong magnetic exchange coupling, which was found to be JGd–rad = –7.2 cm-1 for 1-Gd. Combined with the highly anisotropic TbIII and DyIII ions in 1-Tb and 1-Dy, the strong Ln-rad magnetic exchange coupling led to zero-field SMM behaviour and waist-restricted magnetic hysteresis loops. These dinuclear complexes serve as ideal models for understanding the magnetic interactions promoted by tetrazinyl radical bridges with 4f elements.
Taking advantage of the Cp* ancillary ligands and the steric effects imposed by their bulkiness, the chelate 3,6-bis(3,5-dimethyl-pyrazolyl)-1,2,4,5-tetrazine (bpytz) was incorporated into a series of radical-bridged Ln2 metallocenes: [(Cp*2LnIII)2(bpytz•−)](BPh4) (where Ln = Gd (2-Gd), Tb (2-Tb), Dy (2-Dy), Y (2-Y) and Er (2-Er)). Notably, it was found that compared to the cis fashion, the trans coordination of the bpytz•− enabled one of the strongest exchange couplings observed in radical-bridged Ln metallocene complexes; JGd–rad = –14.0 cm-1. The strong Ln-rad exchange coupling was further verified by high-frequency EPR (HF-EPR) spectroscopy and computational studies. In-depth analysis of the magnetic properties for 2-Tb, 2-Dy and 2-Er revealed slow magnetic relaxation but different magnetic performance, which was attributed to the intricate electronic differences of the individual LnIII ions.
Altering the electron distribution of the tetrazine ring by introducing electron-donating or withdrawing substituent groups at the 3- and 6-positions of the tetrazine ring affects the strength of the Ln-rad magnetic coupling. To elucidate the true influence of the substitution, a series of radical-bridged Ln2 metallocene complexes featuring the 3,6-dimethyl-1,2,4,5-tetrazine (dmtz) and the 3,6-dimethoxy-1,2,4,5-tetrazine (dmeotz) were synthesized: [(Cp*2Ln)2(dmtz•–)(THF)2](BPh4)·THF (Ln = Gd (3-Gd) and Dy (3-Dy)) and [(Cp*2Ln)2(dmeotz•–)(THF)](BPh4) (Ln = Gd (4-Gd) and Dy (4-Dy)). Cyclic voltammetry, UV-Vis absorption spectroscopy, SQUID magnetometry, as well as theoretical calculations were combined to underline the trends observed in this study, while comparisons to the unsubstituted 1,2,4,5-tetrazine (tz) and the 3,6-dichloro-1,2,4,5-tetrazine (dctz) were made. Both 3-Dy and 4-Dy exhibit slow magnetic relaxation at zero field, while a coercive field of ~5000 Oe was observed for 3-Dy.
Further exploration of the incorporation of tetrazinyl radical bridges into lanthanide metallocene complexes led to tetranuclear radical-bridged complexes: [(Cp*2Ln)4(tz•−)4]⋅3(C6H6) (Ln = Gd (5-Gd), Tb (5-Tb) and Dy (5-Dy)). The very strong JGd–rad1 = –12.0 cm-1 and JGd–rad2 = −7.5 cm-1 promoted by the tz•– bridges led to 5-Ln acting as a molecular entity, with a highly sought-after “giant-spin”, rather than weakly coupled individual spin centres. Both 5-Tb and 5-Dy exhibit slow magnetic relaxation at zero field. However, the electronic differences of the TbIII and DyIII ions resulted in waist-restricted hysteresis loops in 5-Tb, while in 5-Dy, the hysteresis loops were open with a large coercive field of 30 kOe. The giant coercivity obtained for 5-Dy provides a glimpse into the potential of polynuclear radical-bridged Ln SMMs to access systems with enhanced magnetic hardness, a critical aspect when envisioning next-generation storage devices.
A combination of strictly anhydrous and inert synthetic conditions, strong reducing agents, and non-acidic solvents, as well as blocking the accessibility of the nitrogen atoms by coordinating them to LnIII ions, allowed for the stabilization of the first structurally and physically characterized complexes bearing a dianionic tetrazine species: [(Cp*2Ln)2(tz2−)(THF)2]·2THF (Ln = Gd (6-Gd) and Y (6-Y)). Detailed structural analysis, physical characterization, ab initio calculations, as well as comparison to the radical-bridged complexes 1-Gd and 1-Y, support that the tz2– ligand is a closed-shell planar dianion with unique structural features vastly different from those of the dihydro (H2tz), neutral (tz), or radical (tz•−) species.
Employing radical ligands that can store unpaired electrons might be the key to promote strong magnetic interactions in polynuclear Ln SMMs. Incorporation of both radical and dianionic tetrazine bridges in the same molecular structure allowed for the isolation of the first examples of hexanuclear radical-bridged Ln metallocene complexes: [Cp*10Ln6(dmeotz2–)(dmeotz•–)4(THF)4](BPh4)2 (Ln = Gd (7-Gd) and Dy (7-Dy)). In-depth analysis of the magnetic properties of 7-Gd revealed the presence of strong Ln-dmeotz•– magnetic coupling, while 7-Dy exhibited thermally-activated magnetic relaxation at zero field. To unravel the observed trends of the magnetic properties of 7-Ln, magneto-structural correlations were employed.
The collective results of this dissertation provide critical insights into the role of s-tetrazinyl radicals in radical-bridged Ln SMMs
Characteristics of people with bipolar disorder I with and without auditory verbal hallucinations
No full textAbstract Background Approximately half of people with bipolar disorder type I (BD-I) report the presence of psychotic symptoms at least at some point during their illness. Previous data suggest that more than 20% of people with BD-I report the presence of auditory verbal hallucinations (AVHs), or “voice-hearing” in particular. While work in other disorders with psychotic features (e.g., schizophrenia) indicates that the presence vs. absence of AVHs is associated with poorer clinical outcomes, little is known about their effects on clinical and socioeconomic features in BD-I. Methods We investigated whether people with BD-I (N = 119) with AVHs (n = 36) and without AVHs (n = 83) in their lifetime differ in terms of demographic features and clinical measures. Relations with AVHs and other positive symptoms were explored. Results People with BD-I and AVHs vs. without AVHs had higher manic and positive symptom scores (i.e., higher scores on the hallucinations, delusions, and bizarre behavior subscales). Further, a greater proportion of those with vs. without AVHs reported lower subjective socioeconomic status and tended to have higher rates of unemployment, thus, speaking to the longer-term consequences of AVH presence. Conclusion Our findings suggest that people with BD-I with AVHs exhibit more severe psychotic features and manic symptoms compared to those without. This might be associated with more socioeconomic hardship. More in-depth characterization of people with BD-I with/without AVHs is needed to fully understand this subgroup’s unique challenges and needs. Limitations The modest sample size of the AVH group and a study population with low racial diversity/representation may limit generalizability
Left Out: Challenges Faced by Students with Learning Disabilities in Post-secondary Education at Ontarian Institutions
No full textBy identifying the perceived challenges and successes of students with LDs, the study aimed to understand how these students make sense of their challenges in post-secondary education at Ontarian institutions. Considering the epistemology of constructivism, the study utilized qualitative methodology guided by an interpretivist theoretical perspective rooted in the phenomenological paradigm.
Ten (10) students with LDs from Ontarian post-secondary institutions were recruited to contribute to this study to understand the essence of students' experiences, including factors that contribute to overcoming their challenges. Five (5) faculty members from Ontarian post-secondary institutions were also recruited to contribute their experiences dealing with the challenges of these students, including their result-based factors that effectively contributed to their academic successes.
The data analyses yielded two key themes - themes related to challenges and themes related to successes – with several corresponding nested themes. Themes related to challenges indicated that students with LDs had to comply with their respective institutions' psycho-educational assessments to receive accommodations. They experienced concerns about being labeled and stigmatized and found it necessary to conceal their learning disability, which reduced their chances of receiving academic accommodation on time. Their challenges become compounded when they need to deal with preconceptions of parents, peers, and faculty members to become more independent as they adapt to higher education.
Themes related to success indicated that positive interactions with faculty, peers, and service providers are significant in the academic success of students with LDs. The positive impact of their support on these students makes the faculty, peers, and service providers feel the meaning of their role in the student's success. While each student's academic journey was different, there were shared threads of resilience and success. The experiences of challenges of post-secondary students with LDs and their resilience to overcome the challenges presented in this study would contribute to the existing literature that enlightens hope for their potential success