VictorJuiz/thesis huggingface dataset:
Who Lives in Us and How? How Beginning Counsellors Experience Internal Representations of People who were Significant to their Clinical Development

Relationships of teaching and learning play a key role in what counsellors are learning, who they are becoming, and how. This study aims to understand more about the psychological processes by which this takes place. It explores how beginning counsellors experience internal representations of people who were significant to their clinical development (guides). It defines internal representations as (1) a felt presence of the guides that arises internally through emotional, sensory, visceral and other bodily impressions, and inter-personally through replications with others (2) dynamics of narrative voice in counsellors’ stories about these guides. Transcripts of narrative interviews conducted with 5 counsellors who were within their first 5 years of clinical practice were analyzed using the Listening Guide in conjunction with Thematic Analysis. Each counsellor’s stories revolved around a core learning theme that expressed key dilemmas that recurred in the boundaries between self and other. The guides replicated these dilemmas with them, as well as offered new ways to resolve them. Counsellors’ internal and interpersonal phenomena echoed this: they expressed the nature of their relational dilemmas, recalled moments in which guides taught them new approaches to them, and served as means to implement what they had learned. They did so through a felt presence that accompanied and/or merged with the self of the counsellors. Counsellors lost and re-established connection to themselves - their voices of knowing, feeling, action and identity, as well as their knowledges, identities, values and preferred ways of being from outside their clinical worlds - when their stories made contact with these guides. Through a root metaphor of migration, counsellor development is conceptualized as a crossing between worlds that prompts processes, both organic and pressured, of separation and reconciliation within the self.

Keywords: Counsellor development
Counsellor identity
Psychotherapy training
Advisor: Stewart, Suzanne L
Partners and Crime: Contemporary Unions and Desistance from Crime During the Transition to Adulthood

The age-graded theory of informal social control, one of the most influential theories in life-course criminology, purports that marriage is a “turning point” that can discourage offending and explain desistance from crime during the transition to adulthood. However, this theory was developed using a sample of white men who came of age over half a century ago. Since that era, marriage is delayed and increasingly forgone in favour of cohabitation, yet little is known about how cohabitation influences crime. This dissertation updates and extends the theory by examining how contemporary romantic partnerships influence offending, and whether these effects generalize across the intersection of gender and race. Using data from the National Longitudinal Survey of Youth (1997) and employing multilevel models with inverse probability of treatment weights, I estimate the causal effects of cohabitation and marriage on self-reported offending throughout the transition to adulthood. I find that cohabitation does not influence the offending behaviour of white, black, or Hispanic men and women. Although marriage deters offending among some subpopulations, these results suggest that future research in this area must take seriously the scope of the age-graded theory’s generalizability and attend to other scope conditions in addition to gender and race. Furthermore, marriage today is much less common and tends to occur later in the life-course than for previous cohorts. Thus, marriage, and partnering in general, may no longer be powerful explanations of desistance at the population-level or of the “age-crime curve”. The social contexts that bond young adults to society during the transition to adulthood are more heterogeneous and complex than for past cohorts, but the stability of the age-crime curve suggests that these social bonds continue to exert informal social control that promotes desistance from crime. Further research should investigate these complex social contexts to understand the contemporary desistance process.

Keywords: Age Graded Theory
Criminology
Life Course
Sociology
Advisor: Kruttschnitt, Candace
Development of Metal Chelators and Metal Chelating Polymers for Mass Cytometry and Positron Emission Tomography

Metal chelators play various roles in science, technology, and in clinics. Mass cytometry is a flow technique that uses metal ions to quantify the antigens on the surface of cells. New metal-chelating polymers (MCPs) are needed to form stable complexes with multiple Zr ions to be developed into a mass cytometry reagent. Metal chelators attached to antibodies can be radiolabeled to form radioimmunoconjugates (RICs). RICs labeled with radioactive 89Zr can act as imaging probes for a medical imaging technique called positron emission tomography (PET). A new chelator is needed to improve the in vivo stability of the 89Zr-chelator complex. An antibody can be conjugated with MCPs to attach multiple chelators per antibody without over-modifying the antibody. My thesis describes three projects that describe my contribution to 1) developing a new MCP to chelate multiple Zr ions for mass cytometry, 2) synthesis and conjugation of a new chelator called DFO* and my evaluation of the chelator as a 89Zr chelator, 3) synthesis of a MCP, conjugation to a breast cancer targeting antibody and my evaluation of the MCP-antibody conjugate as a RIC. The work described in this thesis identify and address some of the challenges that arise when developing novel MCPs and adopting a novel metal chelator for biological applications.

Keywords: Antibody conjugation
Mass Cytometry
Metal chelator
Polymer
Positron emission tomography
Zirconium
Advisor: Winnik, Mitchell A
The Persistence of Property-owning Personhood in Nineteenth-century U.S. Literature (1845-1913)

This dissertation examines representations of property-owning personhood in crisis in nineteenth-century U.S. literature (1845–1913). I argue that, in response to what historian Charles Sellers calls “the market revolution,” nineteenth-century U.S. writers constructed a transcendental conception of property that elevated property ownership above history, politics, and the market. To preserve the property-owning individual as an ethical and political ideal, nineteenth-century writers separated property from capitalism. Yet alongside this (supposedly) clear-cut opposition is a lingering uncertainty, one that held that property is both the cure for capitalism’s ills and the root cause of the market’s violence. Drawing on political writings by John Locke and Karl Marx, I show how separating property from capitalism proves just as impossible as preventing the instrumentalization of categories such as class, gender and race for capitalist gain. I begin with a discussion of Ralph Waldo Emerson’s opposition between “living property” and “accidental property” in “Self-Reliance.” Here, Emerson describes a form of property that is purified of history and relationality. He laments that property diminishes individual autonomy and increases reliance on the external world. Each subsequent chapter identifies a conceptual challenge to the stability of property-owning personhood: excess and debt, circulation, and racialized ideas of the human. In Chapter One, I argue that both Henry David Thoreau and Harriet Jacobs identify an unfair distribution of surplus and debt as inherent to the logic of property under capitalism. In my second chapter, I show how Edith Wharton’s novels use circulation and gender as the conceptual fields to understand the destruction of property-owning personhood. Chapter Three considers how the “tragic mulatto” genre depicts the limitations of self-ownership and property-owning personhood in two novellas by William Dean Howells and Charles Chesnutt. Both texts chart a dream property’s fabrication out of the ruins of capitalist property. My dissertation closes by extending my arguments about property to the contemporary moment through a close reading of Ramin Bahrani’s 2015 film, 99 Homes. Nineteenth-century U.S. writers’ fantasies about property are fraught with a generative ambivalence particular to property in crisis; their indecision can either threaten or reinforce property’s stronghold on political life.

Keywords: American literature
Nineteenth century
Personhood
Possessive individualism
Property
Advisor: Downes, Paul
Morgenstern, Naomi
Identification of Novel Structural Motifs for Mining the Conformational Space of Boron- and Peptide-based Molecules

Conformation describes the spatial arrangement of atoms in a molecule. While the binding energy between atoms in a molecule determines its structure, the three-dimensional geometry can have considerable flexibility. This has important ramifications for the way molecules interact with each other. This dissertation describes the conformation-derived properties of novel boron- and peptide-based structures, two emerging modalities in drug discovery and subjects of intense contemporary interest. In Chapter 1, a systematic study of boron’s interactions with a range of protein side-chain residues suggests that boron is a unique electrophile in its chameleonic ability to engage protein targets. These mechanistic and structural insights revealed that boron’s properties are nuanced and arise from its uncommon coordination preferences. In Chapter 2, a general method was developed to connect boron- and nitrogen-containing fragments based on the capacity for boryl aldehydes and acyl boronates to undergo reductive amination with various types of amines. This work highlights the untapped potential of boron-substituted iminium ions and enables access to new classes of stable α- and β-aminoboronic acids. In Chapter 3, we report that the MIDA (N-methyliminodiacetic acid) boryl group can act as a chameleon, displaying high migratory aptitude in its tetracoordinate form in one setting, yet migrate as an electrophile under other conditions. The main finding is that hemilability of the B–N bond plays the key role during migration. Based on the mechanistic results, new reactions were designed for the synthesis of hitherto inaccessible boron-based intermediates and endpoints of synthesis. In Chapter 4, the concept of dominant rotors is applied to explore complex energy landscapes of constrained chains of rotors exemplified by amino acids. The observation of unusual conformations of peptide macrocycles that are close in energy was made possible by operating away from equilibrium. These structural insights suggest the existence of unexplored conformations of ring structures and a path to generate them. In Chapter 5, the Pinc ((N-isocyanimino) triphenylphosphorane)-driven macrocyclization reaction was probed with nucleophilic kinetic traps and unveiled a novel iminophosphorane intermediate. Based on these insights, a new macrocyclization reaction was designed to deliver ring structures of various sizes with a novel bis(heteroaryl) motif.

Keywords: Aminoboronic acids
Atropisomers
Boron
Conformational analysis
Macrocycles
Peptides
Advisor: Yudin, Andrei K
Wood and Bamboo Biochars and Their Application in Soils and Biocomposites

Chars (“biochars”, for use in soil amendment, or “biocarbon”, in fuel and other engineering applications) vary greatly in their physico-chemical properties due to the different feedstocks from which they are derived and the variation in thermal response of their lignocellulosic content. In this research, 20 Canadian temperate wood feedstock biochars were tested for their liming capacity via soil incubation (Chapter 2) and effect on seed germination and radicle extension, using the biochars’ leachates (Chapter 3). Subsequently, 3 bamboo species and selected wood species were charred, and the resulting biocarbons applied and tested to determine: the mechanical properties of polypropylene (PP)-based lightweight biocomposites and the extent of nano-layered graphite formation in biocarbons (Chapter 4); and the electrically and thermally conductive properties of polyamide (PA)-based biocomposites (Chapter 5). The 20 wood species were charred at a range of pyrolysis temperatures from 300 to 700 oC, with a residence time of 60 min (“slow pyrolysis”). A subset of 2 feedstocks (Acer saccharum and Populus grandidentata) were charred at 500 and 550 oC with residence times of 1–5 min (“fast pyrolysis”). The elemental nutrient concentrations increased with pyrolysis temperature, while the acidic group concentrations declined. The liming capacity of the biochars produced via slow pyrolysis increased with higher elemental nutrient concentration and lower acidic group concentration, and application of slow pyrolysis biochar leachate promoted both germination and radicle extension. By contrast, lower elemental nutrient concentrations and higher acidic group concentrations were present in the fast pyrolysis biochars, and leachates from these biochars inhibited germination and radicle extension. The bamboo species studied were charred using the slow pyrolysis method at 900, 1100, and 1300 oC, with residence times of 60 and 120 min. Selected bamboo- and wood-PP biocomposites maintained the light polyolefin density of the polymer, with improved mechanical properties due to the porous structure of the biocarbons. The biocarbons’ nano-layered biographite formation and electrical conductivity (EC) increased with higher pyrolysis temperature and duration. In particular, the PA-based biocomposites’ EC increased in the presence of maleic anhydride polypropylene as a hydrophobic-lyophilic thermodynamic balancer. These biocomposites also showed improved thermal conductivity as compared to the neat PA.

Advisor: Thomas, Sean
Sain, Mohini
EEG Features of Working Memory Impairment in Alzheimer’s Dementia and Mild Cognitive Impairment

The presence of working memory impairments in individuals with Alzheimer’s Dementia (AD) or Mild Cognitive Impairment (MCI) is well-accepted; however, the neurophysiological mechanisms contributing to these impairments have not been fully elucidated. Research has reliably shown that oscillatory activity, driven by repetitive and synchronous activity within and between neuronal populations, plays a significant role in memory functioning and can be accurately captured using electroencephalography (EEG). While resting-state studies have identified aberrant oscillatory activity, mainly in those with AD, there is a paucity of research investigating how EEG activity behaves during cognitive processing. As such, the overall objective of this study was to assess the relationship between oscillatory activity and working memory impairments in AD and MCI, with a focus on three EEG features: theta and alpha power, theta-gamma coupling, and theta phase synchronization. We hypothesized that these EEG features would be most impaired in those with AD, while individuals with MCI would present with less significant impairments. Additionally, we hypothesized that each of these features would be associated with working memory performance. In the first study, we found that the AD group demonstrated the smallest increase in theta power following the onset of the 2-back stimulus; while compared to controls, the MCI group demonstrated a smaller increase in theta power on the most difficult 3-back condition. Similarly, in the second study, the AD group demonstrated the lowest level of theta-gamma coupling followed by MCI and HC groups. Finally in the third study, we found that the AD group demonstrated impaired theta phase synchronization between the temporal region and the rest of the brain, while no differences were found between the HC and MCI groups. Our results also demonstrated that each of the EEG features were associated with working memory performance to varying degrees. Taken together, findings from these studies revealed widespread impairments in EEG activity in AD, along with an intermediate and inconsistent level of impairment in those with MCI. Ultimately, this research advances our understanding of the neurophysiological mechanisms underlying working memory impairments in MCI and AD and may help guide the development of novel interventions in the future.

Keywords: Alzheimer’s Dementia
Electroencephalography
Mild Cognitive Impairment
Working Memory
Advisor: Rajji, Tarek K
Mulsant, Benoit H
Three Essays in the Economics of Education

This thesis is made up of three chapters that examine student choices in Canada's higher education system: student choice of major (Chapter 1), of courses (Chapter 2), and to continue in college/university (rather than drop out) (Chapter 3). Chapter 1 studies the gender enrolment gap in Science, Technology, Engineering, and Mathematics (STEM) programs in university. Conducting a survey at a leading Canadian university, I find that female students are more likely to underestimate their relative ranking than male students. In a follow-up randomized experiment, I provided treatment group students with information about their rankings and about expected future incomes for STEM and non-STEM majors. The treated students became 8.5 percentage points more likely to choose a STEM major, and these effects are driven by female students. The analysis indicates that undergraduate students do not correctly estimate their relative performance, and providing students with precise information helps them make more informed choices, encouraging them to change major to a STEM field. Chapter 2 (joint with Robert McMillan and Hammad Shaikh) examines why university students often seek to enrol in less advanced courses despite being eligible for challenging courses that may be more beneficial for the development of their skills. Through experiments, we find that providing an information session significantly increases the probability of eligible first years enrolling in the more rigorous second-year courses. When we send students emails about the advanced courses rather than invite them to an information session, the effects become statistically insignificant. Our results shed light on the determinants of student course selection. Chapter 3 studies how receiving first-year financial aid affects the second-year student re-enrolment decision. After controlling for institution fixed effects, I find that financial aid, despite its potential to improve student re-enrolment, has statistically insignificant effects. In contrast, student attitudes toward higher education do have statistically significant effects on re-enrolment rates: if students believe that it is a "right decision" to pursue post-secondary education, the probability of re-enrolment increases by 3 percentage points. This chapter demonstrates that student attitudes, rather than financial aid, play a key role in determining student decisions to continue studying.

Advisor: McMillan, Robert
Exploring Spatiotemporal Community Assembly using Taxonomic and Functional Dimensions of Biodiversity

Determining how diversity is generated and maintained in ecological communities is a central goal of community ecology and conservation. Ecologists have long aimed to explain the processes responsible for the assembly of communities and although many hypotheses have been proposed, understanding what makes a non-native species successful continues to be the principal question in invasion ecology. Addressing these topics is inherently complex given that the mechanisms that regulate diversity are often dependent on the spatial and temporal scale at which they are quantified and are further complicated by pervasive context dependence. This thesis examines the spatiotemporal changes in, and community assembly processes governing, functional and taxonomic dimensions of biodiversity in fish communities of the Laurentian Great Lakes in response to the establishment of non-native species and extirpation of native species. I show that both taxonomic and functional dimensions of local and regional diversity are increasing over time. Between-community diversity has increased and decreased for functional and taxonomic dimensions of diversity, respectively, indicating the presence of both biotic differentiation and homogenization that is temporally dynamic. Environmental filtering selects for similar species due to a shared affinity for local conditions and explains establishment success of non-native species as well as local and regional patterns of diversity. Community assembly and composition is also highly regulated by dispersal and historical effects due to the glacial history of the region.

Keywords: Biogeography
Biological Invasions
Biotic Homogenization
Community Ecology
Advisor: Mandrak, Nicholas E.
Mechanistic and Regulatory Insights into the Biosynthesis of the Pseudomonas aeruginosa Biofilm Exopolysaccharide Pel

Bacteria routinely live as multicellular communities encased in a self-produced extracellular matrix, or biofilm. Pseudomonas aeruginosa is a model for biofilm formation and utilizes the Pel polysaccharide in its biofilm matrix. Biosynthesis of bacterial polysaccharides generally follows one of three mechanisms, however the mechanism utilized for Pel production remains unclear. We employed mutual stability analyses, cellular fractionation, and co-immunoprecipitation from P. aeruginosa, as well as bacterial adenylate cyclase two-hybrid assays in E. coli, to define a complex at the inner membrane composed of PelDEFG. This allowed us to propose that Pel biosynthesis proceeds via a synthase-dependent mechanism. C-di-GMP regulates biofilm formation in nearly all bacteria, however the mechanism(s) of signalling specificity is unknown. One hypothesis is that c-di-GMP metabolic proteins directly interact with effectors to achieve specificity. We performed co-IP of PelD coupled with mass spectrometry to identify interacting diguanylate cyclases or phosphodiesterases (PDEs). Among others, the PDE BifA co-purified with PelD. We showed that the transmembrane and periplasmic regions of BifA are dispensable for this interaction. Mutation of the GGDEF sequence motif exhibited varying effects on PDE activity. However, mutation of the GGDEF or EAL motifs eliminated interactions with PelD, suggesting that PDE activity, PelD interaction, and biofilm formation are not always coupled. The majority of information about biofilm production and regulation comes from Gram-negative bacteria. Much less is understood about the equivalent processes in Gram-positive organisms. A computational algorithm unexpectedly identified pel operons in many Gram-positive genera. We focused on characterization of the locus from Bacillus cereus. Deletion of any of the genes in the pelDEAFG operon completely abrogated biofilm formation. Lectin and antibody binding revealed pelF-dependent recognition of extracellular material, and B. cereus biofilms were disrupted by P. aeruginosa PelA hydrolase, an endo-a-1,4-N-acetyl-galactosaminidase. These data support the structural similarity of the B. cereus and P. aeruginosa Pel polysaccharides. Interaction between B. cereus PelD and c-di-GMP was analyzed by isothermal titration calorimetry, which revealed binding dependent on the RxxD motif of the GGDEF domain. Mutation of this motif in vivo completely abrogated biofilm formation. Collectively, this data reveals that functional pel loci are widely distributed in Gram-positive bacteria.

Keywords: biofilm
c-di-GMP
Pel polysaccharide
Pseudomonas aeruginosa
Advisor: Howell, P. Lynne