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Experimental evaluation of the wicking and reinforcement functions of wicking nonwoven geotextile-geogrid composite in roads
No full textRoad performance is significantly enhanced by incorporating geosynthetics through their reinforcement and drainage functions. This study introduces a new geosynthetic that integrates all these functions. It is made of biaxial polypropylene geogrids heat-bonded to wicking nonwoven geotextiles (WNWGs). Unlike the wicking woven geotextiles comprising deep-grooved fibers, WNWGs are chemically treated to be hydrophilic and thus possess rapid wetting and wicking properties while preserving the large lateral drainage functionality of conventional nonwoven geotextiles. To assess the wicking behavior of the geotextile, a series of wicking tests were conducted in water alone and saturated soils under controlled temperature and relative humidity. Additionally, contact angle measurements and microscopic analyses with Scanning Electron Microscopy (SEM) were conducted to elucidate the underlying wicking mechanisms. To assess the combined reinforcement and wicking performance of the new composite, a series of model tests including rainfall simulation and plate loading tests were performed on the WNWG-geogrid composite reinforced bases over weak subgrade using a customized model test apparatus. The results confirmed that the inclusion of WNWG-geogrid composite significantly enhanced drainage, stiffness, and bearing capacity of road bases. The findings from this study demonstrate the promising performance of this new composite and provides valuable reference for full-scale tests and applications in roads.Graduate2025-12-0
Does chronic stress alter reelin in the entorhinal cortex?
No full textChronic stress (CS) is a risk factor for depression and Alzheimer’s disease (AD). The entorhinal cortex (EC) is the region first showing deterioration in AD. Reelin, which regulates synaptic plasticity, is dysregulated in the hippocampus following CS, in depression and AD, and in the EC following age-related cognitive decline. To examine the effect of CS on reelin+ cells in the EC, 36 rats underwent a cyclic CS model of recurring depression. A subset of rats received an injection of reelin on the last day to determine whether reelin treatment reverses depression-like behaviour and restores reelin in the EC. Reelin treatment reversed depression-like behaviour, but no effect of CS on EC reelin+ cell density was observed, suggesting that CS does not affect EC reelin as it does in other regions. Correlations were examined between reelin+ cell density, forced swim test immobility, and spatial memory. There was no relationship between reelin+ cell density and immobility time, however there was a significant correlation between spatial memory and reelin cell density in males. This correlation was disrupted with chronic stress but successfully recovered with a reelin injection, suggesting a relationship between spatial memory and reelin levels in the EC.Jamie Cassels Undergraduate Research Awards (JCURA)UndergraduateReviewe
“Hors d’état de jouer”: Illness at the Comédie-Française in the 17th and 18th centuries
No full textLetters at the archival library of the Comédie-Française up to the 19th century pertaining to illness, accidents and poor health are transcribed and analysed for statistical trends and anecdotal insight into the effect of these absences on the theatre institution and the performance of theatre. Criteria assessed include gender, time frame, frequency of conditions and remedies (if applicable) and the purpose and content of letters. The results of the analyses suggest that women employed at the Comédie-Française during the studied time period were more likely to request time off due to indispositions than their male counterparts. Other trends are likewise revealed, including differences in rates of mention of common ailments between women and men and the demographic of actors who most often wrote time-off requests to the theatre. The actors' original manuscripts provide unique anecdotal insight into the work culture and approach towards illness during the time period. The information found in these results is an asset to future analyses of daily theatre programming and to further research on the challenges that performance artists face in their profession, a key issue to better understanding the cultural history of the performance arts.Valerie Kuehne Undergraduate Research Awards (VKURA)UndergraduateReviewe
Serial Verb Constructions and Auxiliary Verb Constructions in SENĆOŦEN
Get PDFSerial verb constructions (SVCs) and auxiliary verb constructions (AVCs) are understudied phenomena, particularly within the Salish language family. SENĆOŦEN is a dialect of Northern Straits Salish spoken in parts of British Columbia and Washington state. Building off existing SENĆOŦEN documentation, I present and examine a corpus of examples of SVCs in SENĆOŦEN, which is appended to this thesis. This corpus also includes examples of AVCs that contain the verb yeʔ ‘go.’ This thesis is divided into two parts: description and analysis. The former is contained in Chapter 1 and Chapter 2, which describe relevant SENĆOŦEN grammar and the corpus data. The latter is found in Chapter 3 and Chapter 4, in which I analyze the unique verb yeʔ ‘go’ and provide a Minimalist analysis of SENĆOŦEN AVCs and SVCs. I argue that, in an SVC, each verbal component can be as large as AspP. Additionally, I argue that some multi-verb constructions containing the verb yeʔ ‘go’ are better analyzed as AVCs, in which yeʔ ‘go’ is the head of an AuxP located between TP and AspP. The corpus of SENĆOŦEN SVCs and AVCs is appended in an effort to contribute to the overall body of research for the language and to the field of Salish syntax.Graduat
Exploration of applications of photon-counting detector computed tomography (CT) using a table-top CT system
No full textComputed Tomography (CT) is an essential diagnostic tool in healthcare, widely used for various applications including cancer detection, vascular disease evaluations, and radiation therapy planning. Recent advancements in photon-counting detector (PCD) technology have led to the development of photon-counting detector CT (PCD-CT), a promising innovation offering high spatial resolution and superior contrast-to-noise ratios compared to traditional CT. PCD-CT excels in detecting and characterizing small structures in various body parts, enhancing tissue differentiation, and material decomposition, thus potentially improving disease diagnosis and radiotherapy treatment planning. This research explores the applications of PCD-CT using a bench-top system, offering insights into its potential benefits over conventional CT systems. Despite its limitations in fully representing a clinical CT system, the bench-top model provides flexibility in assessing clinically useful features. This dissertation investigates four key applications of PCD-CT: material decomposition, multi-contrast imaging, metal artifact reduction, and high-resolution imaging.
We investigated the material decomposition capabilities of our bench-top PCD-CT scanner using a dual-energy CT (DECT) method for extracting effective atomic number (Zeff) and relative electron density (ρe) of tissues. We demonstrated that the method with PCD-CT was more accurate in extracting Zeff and ρe for a set of electron density phantom materials with known Zeff and ρe than the method with DECT. In addition, four tissue types were correctly identified in an ex-vivo tissue sample and an injected gold contrast agent was separated from the other four tissue types using K-edge subtraction imaging.
Multi-contrast imaging was demonstrated in a phantom model with four contrast agents: gadolinium, dysprosium, lutetium, and gold. The four contrast agents were inserted into the same cylindrical phantom and imaged in one scan. Using K-edge subtraction, we were able to demonstrate complete separation and accurate quantification of the four contrast agents, even of gadolinium and dysprosium, which have K-edge energies of 50.2 keV and 53.8 keV, respectively. Additionally, we optimized the acquisition parameters for the various contrast agents.
We also developed a novel metal artifact reduction (MAR) method using PCD-CT. As metal attenuates fewer higher energy x-rays than low energy x-rays, we showed that the
high-energy range of 100–110 keV demonstrated fewer metal artifacts. The high energy range is separable from the other x-ray data with the PCD. With this in mind, we developed
trace replacement metal artifact reduction (TRMAR). The metal traces in the corrupted conventional CT sinogram space are replaced with the high-energy trace data from the 100-110 keV range. With this, we maintained the contrast and image quality of the full spectrum conventional CT image and also kept the reduced metal artifacts from the high energy data.
Finally, we demonstrated the high spatial resolution of our PCD-CT system by imaging coronary artery stents and comparing the same stents imaged with two conventional CT scanners. PCD-CT demonstrated more accurate measurement of the stent strut, or wire, width, stent lumen diameter, and lumen CT number compared to conventional CT. In addition, this led to more accurate 3D representations of the stents. The higher accuracy of strut width and stent visualization is due to the higher spatial resolution of the PCD-CT system and the reduced metal and blooming artifacts it offers over conventional CT.
Each of these applications demonstrates the significant potential of PCD-CT in enhancing medical diagnostics and treatment, particularly in cardiovascular imaging, highlighting its
diverse contributions to the field of medical imaging.Graduat
Temperature dependent Korteweg stress coefficient from the Enskog-Vlasov equation
Get PDFEnskog-Vlasov equation—a nonlinear partial-integro-differential equation, provides a robust framework for analyzing liquid dynamics and phase transition. The Vlasov force expanded using Taylor series yields Korteweg stress with two constant coefficients. The first coefficient yields the van der Waals like contribution to equilibrium pressure, while the second coefficient determines the interfacial stresses/surface tension. In this article, we express the second Korteweg constant coefficient as a function of temperature. The developed model effectively captures the liquid-vapor interfacial region in equilibrium, reproducing the sharp interfacial structure predicted by the full Enskog-Vlasov equation. Additionally, we compare our results with those obtained through a particle-based approach, as studied by Frezzotti et.al (2019) [“Direct simulation Monte Carlo applications to liquid-vapor flows,” Physics of Fluids 31, 6 (2019)]. The proposed model balances simplicity with computational efficiency, comprehensively examined within the paper.FacultyReviewe
Counting X-free sets
Get PDFLet X be a finite subset of the integers. A set A contained in [n]^d is X-free if it does not contain a copy of X, that is subset of the form b+r*X, for any r > 0 and b in the d-dimensional real numbers. Let r_X(n) denote the cardinality of the largest X-free subset of [n]^d. In this thesis we explore X-free sets in three ways. Firstly, we give an exposition of a standard multidimensional extension of Behrend's construction that gives a lower bound on r_X(n) for all |X| >= 3. Next, we lower bound the number of copies of X guaranteed in subsets with cardinality larger than r_X(n). This is a supersatuation}result that uses the previously demonstrated lower bound on r_X(n). Finally, using our supersaturation result, we show that for infinitely many values of n the number of X-free subsets is 2^{O(r_X(n))}. This result is obtained using the powerful hypergraph container method. Further, it generalizes previous work of Balogh, Liu, and Sharifzadeh and Kim.
This thesis includes joint work with Natalie Behague, Joseph Hyde, Natasha Morrison, and Jonathan A. Noel.Graduat
The Heisenberg Spectral Triple and Associated Zeta Functions
Get PDFThe construction of Butler, Emerson, and Schultz [2] produced a certain spectral
triple, which they called the Heisenberg cycle, by way of the quantum mechanical annihilation and creation operators, d/dx ± x, along with their relationships to the harmonic
oscillator, -d^2/dx^2 + x^2; Where all of these operators are de fined (initially) to act on
smooth functions over R. In particular, their Heisenberg cycle was over a crossed-product
generated by the natural translation action on the (commutative) C*-algebra
of uniformly continuous, bounded, functions on R.
In this thesis, we generalize the Heisenberg cycle of Butler, Emerson, and Schultz to
allow for the construction of a spectral triple over a crossed-product generated by the
natural translation action on the C*-algebra of uniformly continuous, bounded, functions
on a Euclidean space, V , of arbitrary finite dimension n. For such a generalization,
the annihilation and creation operators are replaced using the exterior derivative and
codifferential, exterior and interior multiplication by a certain differential 1-form, and
the relationship these four operators have to the n-dimensional harmonic oscillator acting
on differential forms. Similarly to [2], we will show that our generalized Heisenberg
cycle provides a new way of producing spectral triples over crossed-products of the
form C(M) ⋊_α Γ, where Γ is a discrete subgroup of V and α : V x M →M is a smooth
V -action on a compact manifold M.
In Chapter 1, we introduce the problem and briefly discuss some historical background
behind Alain Connes program of noncommutative geometry, as well as touch
on some elementary constructions in multi-linear algebra. Chapter 2 is where we de ne
the classes of differential forms which appear most frequently in this thesis. Therein,
we also rigorously de fine the operators mentioned in the paragraph above, and use
them to produce the so-called Dirac-Heisenberg which will be associated to our generalization of the Heisenberg cycle. For the first half of Chapter 3, we discuss some
basic C*-algebra theory and introduce the crossed-product native to the Heisenberg
cycle. In the latter half of that chapter, we verify that our Heisenberg cycle satis es
the conditions of a spectral triple, compute an integral formula for the resulting ζ-functions, and show how one uses the Heisenberg cycle to produce spectral triples over
crossed-products generated by smooth actions of V on compact manifolds.Graduat
Unsettling narratives: Climate action beyond settler environmentalism though the revitalization of Indigenous Law
Get PDFThis thesis explores how settler environmentalism functions as a colonial structure, perpetuating environmental racism and marginalizing Indigenous and racialized communities through exclusionary narratives and solutions. Using narrative theory in law, it critiques the apocalyptic framings often employed in environmental movements, which prioritize settler perspectives while obscuring systemic inequalities. By engaging with decolonial scholarship and Indigenous knowledge systems, the research highlights the ontological and legal implications of alternative approaches to climate action that challenge colonial paradigms. It argues for a reimagined environmental legal framework that centers justice, equity, and community-driven solutions, offering pathways toward dismantling the colonial legacies embedded in contemporary environmental policy.Graduat
"Into the space of being a sociologist": Student, community partner, and faculty experiences of community-engaged learning
Get PDFThis study explores the experiences of undergraduate students, community partners, and faculty in one Community-Engaged Learning (CEL) course. Building on the work of previous CEL scholarship, data was collected across the eight-month course using mixed methods (including surveys, focus groups, interviews, content analysis, and observations) in order to answer the research questions: What are the primary benefits and challenges to students, community partners, and instructor in one undergraduate community-engaged learning course? In what ways do their experiences (benefits and challenges) intersect? The findings demonstrate that while stakeholders experience differing benefits and challenges due to their context-specific perspectives, they also share key benefits and challenges which underscore the transformative potential of CEL.Graduat