VictorJuiz/thesis huggingface dataset:
Gaze Control as a Marker of Self-other Differentiation: Implications for Sociocognitive Functioning and Close Relationship Quality

An individual`s eyes provide a wealth of information during social interactions. The present research investigates the social adjustment implications of one gaze behaviour, specifically, shared attention, which is the tendency to follow an interlocutor`s directed gaze to attend to the same object or location. Recent clinical research suggested that gaze control reflects the capacity to differentiate self from other at the attentional level, since patient populations with poor gaze control abilities (i.e., schizophrenic patients) were also found to exhibit difficulty in differentiating between the self and another agent. Four studies were conducted to examine whether flexible gaze following behavior, specifically the ability to inhibit gaze-following, when the situation warrants, would be positively linked with two markers of adaptive social functioning: sociocognitive abilities and self-close other(s) differentiation. Based on previous research that gaze cues linked to upright (but not inverted) faces trigger reflexive gaze following mechanisms, an upright face condition was used to assess social cueing mechanisms and an inverted face condition, as a control for non-social cueing mechanisms in a gaze control task with realistic (Study 2) and schematic faces (Studies 1, 3, and 4). Studies 1-4 showed that more flexible gaze following behavior predicted superior sociocognitive abilities, as indexed by higher capacity to infer the mental states of others in both young and older adults (Studies 1-3), as well as in clinical populations (i.e., Parkinson’s Disease [PD] patients, Study 4). Studies 2-4 further revealed that poorer gaze control predicted decreased self-close other differentiation in both younger and older adults. In Study 2, poorer gaze control performance characterized young adults from enmeshed family systems, which allow limited private space and emotional autonomy. In Studies 3 and 4, poorer gaze control predicted decreased cognitive-affective differentiation from one’s spouse and lower marital quality in healthy elderly couples (Study 3) and elderly couples, where one spouse had PD (Study 4). The present findings argue for the existence of a unified sociocognitive network, perpetually shaped by one’s interpersonal history, and which encompasses perceptual mechanisms, specialized for face and gaze processing and higher-order cognitive mechanisms, specialized for processing the meaning (s) of social environments.

Keywords: gaze following
enmeshment
Theory-of-mind
Working Memory
Relationship Satisfaction
Advisor: Moscovitch, Morris
Schimmack, Ulrich
Combinatorial Microscopy of Molecular Interactions at Membrane Interfaces

Biological membranes are heterogeneous two-dimensional fluids composed of lipids, sterols and proteins that act as complex gateways and define the cell boundary. The functions of these interfaces are diverse and specific to individual organisms, cell types, and tissues. Membranes must take up nutrients and small molecules, release waste products, bind ligands, transmit signals, convert energy, sense the environment, maintain cell adhesion, control cell migration, and much more while forming a tight barrier around the cell. The molecular mechanisms and structural details responsible for this diverse set of functions of biological membranes are still poorly understood, however. Developing new tools capable of probing and determining the local molecular organization, structure, and dynamics of membranes and their components is critical for furthering our knowledge about these important cellular processes that are often linked to health and diseases. Combinatorial microscopy takes advantage of the rich properties of light (intensity, wavelength, polarization, etc.) to create new forms of imaging that quantify the motions, orientations, and binding kinetics of the sample’s biomolecular constituents. These new optical imaging modalities can also be further combined with other types of microscopy to produce spatially correlated micrographs that provide complementary pieces of information about the sample under investigation that would otherwise remain hidden from the observer if the two imaging techniques were applied independently. The first part of this thesis provides a detailed account of the construction of a specialized hybrid microscopy platform that combines polarized total internal reflection fluorescence microscopy (pTIRFM) with atomic force microscopy (AFM) for the purpose of studying fundamental sterol-lipid and antimicrobial peptide-lipid interactions in model membranes. The second half describes a combined pTIRFM and Förster resonance energy transfer (FRET) imaging method to elucidate the oligomeric state and spatial distribution of carcinoembryonic-antigen-related cell-adhesion molecules (CEACAMs) in the membranes of living cells.

Keywords: atomic force microscopy
fluorescence polarization microscopy
total internal reflection fluorescence microscopy
FRET microscopy
model membranes
supported lipid bilayers
antimicrobial peptides
charge-cluster mechanism
CEACAM
membrane protein
dimerization
oligomerization
combinatorial microscopy
AFM
pTIRFM
TIRFPM
Advisor: Yip, Christopher M.
Molecular Population Genetic Consequences of Evolutionary Transitions from Outcrossing to Selfing in Plants

The transition from cross-fertilization to predominant self-fertilization is considered the most common evolutionary transition in flowering plants. This change in mating system has profound influences on the amounts and patterns of genetic diversity within and among populations, and on key genetic and demographic processes. The main goal of my thesis is to determine the molecular population genetic consequences of this transition in the annual neotropical aquatic plant Eichhornia paniculata (Pontederiaceae) using DNA sequence from individuals sampled from throughout the species’ geographic range. Populations exhibit a wide range of mating patterns associated the evolutionary breakdown of tristyly facilitating specific contrasts between outcrossing and selfing populations. Analysis of molecular variation supported the hypothesis of multiple origins of selfing, including the evolution of two morphologically distinct selfing variants from Central America and the Caribbean. A survey of 10 nuclear loci from 225 individuals sampled from 25 populations demonstrated the joint influence of mating system, population size and demographic bottlenecks in affecting patterns of nucleotide variation. Small selfing populations exhibited significantly lower genetic diversity compared with larger outcrossing and mixed mating populations. There was also evidence for higher population differentiation and a slower decay of linkage disequilibrium in predominately selfing populations from the Caribbean region. Coalescent simulations of the sequence data indicated a bottleneck associated with colonization of the Caribbean from Brazil ∼125,000 years ago. To investigate the consequences of transitions from outcrossing to selfing across the genome, I used high-throughput, short-read sequencing to assemble ~27,000 ESTs representing ∼24Mbp of sequence. Characterization of floral transcriptomes from this dataset identified 269 genes associated with floral development, 22 of which were differentially expressed in three independently derived selfing lineages compared to an outcrossing genotype. Evidence for relaxed selection in selfing lineages was obtained from an analysis of a subset of ~8000 orthologous sequences from each genotype, as predicted by theory. Selfing genomes showed an increase in the proportion of nonsynonymous to synonymous changes and relaxation of selection for codon usage bias. My thesis represents the most detailed investigation to date of the molecular population genetic consequences of intraspecific variation in the mating systems of plants.

Keywords: evolutionary genetics
population genetics
Advisor: Barrett, Spencer C. H.
Approaches Incorporating Evidence for Population Stratification Bias in Genetic Association Analyses Combining Individual and Family Data

Statistical methods that integrate between-individual (IA) and within-family (FA) genetic association analyses can increase statistical power to identify disease susceptibility genes, however combining IA and FA is valid only when the IA are free of population stratification bias (PSB). Existing methods initially test for PSB by comparing IA and FA results using an arbitrary testing level αPSB, typically 5%. Combined analyses are performed if no significant PSB is detected, otherwise analyses are restricted to FA. As a novel alternative, we propose a weighted (WGT) framework that combines the estimate from the most powerful analysis subject to PSB with the most powerful robust FA estimate, using weights based on the p-value from the PSB test. The WGT approach generalizes existing methods by using a continuous weighting function that depends only on the observed PSB p-value instead of a binary one that also depends on specification of an arbitrary PSB testing level αPSB. Simulations of quantitative trait and case-control data show that in comparison to existing methods, the WGT approach has 5% type I error closer to the nominal level, increased (decreased) accuracy for larger (smaller) PSB levels, and overall increased positive predictive value. The resulting PSB correction is SNP-specific and provides a good compromise between type I error control and power in candidate gene or confirmation studies limited to few loci, when PSB is likely and there are no additional empirical data available to correct PSB. We applied the WGT approach to a case-control study of childhood leukemia and a study of diabetes complications with time-to-event outcomes derived from repeated measurements obtained over 17 years of follow-up. To directly analyze the longitudinal measurements without specification of event thresholds, we developed fully Bayesian latent change-point time (LCPT) models for IA and FA. In analogy with the WGT approach, we also considered an extended LCPT model incorporating PSB evidence in analyses combining IA and FA.

Keywords: genetic association studies
population stratification bias
individual-level analyses
family-based analyses
Advisor: Bull, Shelley B.
A Social Theory of Knowledge

We rely on science and other organized forms of inquiry to answer cardinal questions on issues varying from global warming and public health to the political economy. In my thesis, which is in the intersection of philosophy of science, social epistemology, and science and technology studies, I develop a social theory of knowledge that can help us tell when our beliefs and theories on such matters amount to knowledge, as opposed to mere opinion, speculation, or educated guess. The first two chapters discuss relevant shortcomings of mainstream analytic epistemology and the sociology of knowledge, respectively. Mainstream epistemology regards individuals, rather than communities, as the bearers of knowledge or justified belief. In Chapter 1, I argue that typically, only an epistemic community can collectively possess sufficient justification required for knowledge. In Chapter 2, I present a case study in computer science that militates against the sociological understating of knowledge as mere interest-based agreement. I argue that social interests alone cannot explain the unfolding of the events in this case. Rather, we must assume that knowledge is irreducible to social dynamics and interests. In Chapter 3, I begin my positive analysis of the social conditions for knowledge. I explore the question of when a consensus is knowledge based. I argue that a consensus is knowledge based when knowledge is the best explanation of the consensus. I identify three conditions – social diversity, apparent consilience of evidence, and meta agreement, for knowledge being the best explanation of a consensus. In Chapter 4, I illustrate my argument by analyzing the recent controversy about the safety of the drug Bendectin. I argue that the consensus in this case was not knowledge based, and hence the deference to consensus to resolve this dispute was unjustified. In chapter 5, I develop a new theory of the logical relations between evidence and social values. I identify three roles social values play in evidential reasoning and justification: They influence the trust we extend to testimony, the threshold values we require for accepting evidence, and the process of combining different sorts of evidence.

Keywords: social epistemology
philosophy of science
knowledge
consensus
evidence
science and technology studies
testimony
social values
Advisor: Chakravartty, Anjan
Awakening the Calabrian Story: The Diverse Manifestations of Acquiring Knowledge

It all began in the village. We would wake up with the sun, we would rest our laboured bodies underneath the moon. Gli vecchi (old folks) often told us: “In the end, all that will remain is our story. Nothing else really matters.” This thesis “Awakening the Calabrian Story: The Diverse Manifestations of Acquiring Knowledge” will take you into the lives of ten Southern Italian women from Calabria. They will lure you back to their villages: their place of birth, their hearth, to the midst of the olive trees. Their stories will then migrate to Canada, as these women take their first steps on Pier 21. “In the end, all that matters is our stories.” This thesis will give voice to ten Southern Italian women who will tell the world what, to them, matters most. They will tell their tales and pass on the wisdom they have learned along the way. With each breath and each step, they are always growing, never remaining the same. They go along and live out their villages wherever the thread takes them. This thesis itinerary will begin in the village, follow a journey across the Atlantic Ocean to a life in Canada. Chapter One: (Introduction) will outline and describe the background, purpose and objectives, on this journey of awakening. Chapter Two: (Literature Review) will look at pedagogical perspectives in curriculum theory. Chapter Three: (Methodology) will focus on the research methodology applied throughout this thesis process. Chapter Four: (Stories as Data) will lure readers into the personal lives and experiences of participants. Chapter Five: (Interpretation of Stories) will reveal the analysis of acquired knowledge as reported by participants. This thesis itinerary will continue and conclude by the fireside with a collection of Calabrian folktales told by these participants, and translated from the Calabrian dialect into English.

Keywords: folklore
storytelling
Calabrian
Divine Mother
immigration
portraiture
literacy
Italian
Italian Canadian Women
Italian Women
Donne Calabrese
Donne Italiane
story
narrative
qualitative
biographies
Pier 21
Paese Mio
Advisor: Booth, David
Extended Fluid-dynamic Modelling for Numerical Solution of Micro-Scale Flows

This study is concerned with the development of extended fluid-dynamic models for the prediction of micro-scale flows. When compared to classical fluid descriptions, such models must remain valid on scales where traditional techniques fail. Also, knowing that solution to these equations will be sought by numerical methods, the nature of the extended models must also be such that they are amenable to solution using computational techniques. Moment closures of kinetic theory offer the promise of satisfying both of these requirements. It is shown that the hyperbolic nature of moment equations imbue them with several numerical advantages including an extra order of spacial accuracy for a given reconstuction when compared to the Navier-Stokes equations and a reduced sensitivity to grid irregularities. In addition to this, the expanded set of parameters governed by the moment closures allow them to accurately model many strong non-equilibrium effects that are typical of micro-scale flows. Unfortunately, traditional moment models have suffered from various closure breakdowns, and robust models that offer a treatment for non-equilibrium viscous heat-conducting gas flows have been elusive. To address these issues, a regularized 10-moment closure is first proposed herein based on the maximum-entropy Gaussian moment closure. This mathematically well-behaved model avoids closure breakdown through a strictly hyperbolic treatment for viscous effects and an elliptic formulation that accounts for non-equilibrium thermal diffusion. Moreover, steps toward the development of fully hyperbolic moment closures for the prediction of non-equilibrium viscous gas flow are made via two novel approaches. A thorough study of each of the proposed techniques is made through numerical solution of many classical flow problems.

Keywords: Moment Closures
Mico-Scale Flows
Advisor: Groth, Clinton P. T.
Investigation of Coherence and its Decay Mechanisms in an Optical Lattice

In this thesis, I report on experiments with cold 85Rb atoms in a far-detuned one-dimensional optical lattice. These experiments are focused on creating efficient coupling between the quantized vibrational states of atoms in the optical lattice, on controlling and maintaining coherence between the vibrational states, and on developing a spectroscopy method to characterize the decay of coherence. First, I present an experimental study of the application of simple and compound pulses consisting of time-dependent spatial translations to coupling vibrational states of ultracold 85Rb atoms in the optical lattice. Experimental results show that a square pulse consisting of lattice displacements and a delay is more efficient than single-step and Gaussian pulses. The square pulse can be seen as an example of coherent control. Numerical calculations are in strong agreement with the experimental results. In addition, it is shown numerically that the vibrational state coupling due to such lattice manipulations is more efficient in shallow lattices than in deep lattices, in which the coupling probability approaches the harmonic oscillator limit. Next, the effectiveness of these pulses in reviving oscillations of atoms in vibrational superposition states using a pulse-echo technique is examined. Experimental results show that the square and Gaussian pulses result in higher echo amplitudes than the single-step pulse. These echo amplitudes are an order of magnitude larger than the echo amplitudes observed previously for the motional states of atoms in optical lattices. With the aim of the optimized square echo pulse, echo amplitude is measured at much longer times, where a surprising coherence freeze (plateau) is observed. To investigate mechanisms responsible for the observed echo decay and the coherence freeze, we developed a new two-dimensional pump-probe spectroscopy technique to monitor the evolution of frequency-frequency correlations in the system, a necessary input for understanding the decay of coherence. Through this 2D technique, we have characterized the temporal decay of frequency memory and through our simulations we find that coherence freeze is related to the shape of this memory loss function. This technique is general in that it can be applied in a variety of quantum information candidate systems to probe the nature of their decoherence.

Keywords: Optical Lattice
Vibrational State Coherence
2D Spectroscopy
Advisor: Steinberg, Aephraim
Teacher Training In A Proactive Approach To Classroom Behaviour Management: Teacher and Student Outcomes

The present study was undertaken to evaluate the effectiveness and impact of a brief teacher training program in proactive classroom management (PCM), on both teacher and student outcomes. The teacher training program was conducted in a large, inner city public school and was designed as an efficient and cost-effective approach to assisting school personnel in the prevention of off-task and disruptive student behavior. Four groups of teachers (N=16) participated in a single, 4-hour workshop that focused on didactic and performance-based training of such PCM procedures as building rapport, priming for transitions, scaffolding for success, building child tolerance to classroom stressors and teaching replacement behaviours. The program was implemented using a multiple baseline design across groups of teachers. Data were collected through classroom observations of teacher skill implementation and student behaviour (two students in each classroom who presented with behavioural challenges were observed), as well as pre and post self-report rating scale measures of teacher attributions and perceptions and student behaviour. Visual and statistical analyses of group and overall teacher data revealed significant increases in the use of reinforcement and antecedent strategies, reported use of rewards as an intervention strategy, reported levels of confidence in their ability to manage student misbehaviour, and a shift in teachers’ views of student misbehaviour as being more temporary rather than chronic. Significant decreases in teacher reactive responses and reported levels of student inattention and overactivity were also demonstrated. With respect to students, visual and statistical analyses of group and overall data revealed increases in student on-task non-disruptive behaviour and reported levels of self-reliance. Student disruptive and off-task behaviour were significantly reduced. Despite several limitations, the results of the present study demonstrate that student problem behaviour can be efficiently and effectively managed in the classroom without the use of reactive strategies.

Keywords: classroom behaviour managment
teacher training
behaviour management
proactive behaviour management
disruptive behaviour
proactive classroom management
Advisor: Ducharme, Joseph