VictorJuiz/thesis huggingface dataset:
Developmental Stage-dependent Effects of Embryonic Ethanol Exposure on Social Behaviour and Potential Underlying Mechanisms in Adult Zebrafish: A Model for FASD
Keywords: Dopamine
Fetal Alcohol Spectrum Disorder
Gene expression
Isotocin
Social behaviour
Zebrafish

Fetal Alcohol Spectrum Disorder (FASD) is characterized by a variety of morphological, behavioural, and cognitive deficits, including life-long learning disabilities and social dysfunction. FASD is a highly variable disorder, and symptoms range from mild to severe despite similar drinking patterns in mothers. One of the hypotheses proposed to explain this variability is the timing of alcohol consumption, or in other words, the developmental stage at which the embryo is exposed to alcohol. Due to their highly social nature, the zebrafish is becoming a popular model organism for investigating social deficits that arise from embryonic ethanol exposure. Previous studies in zebrafish have observed ethanol administered at 24 hours post fertilization (hpf) resulted in abnormal social behaviour accompanied by lower levels of dopamine and serotonin in the brain, however, little is known about how ethanol alters social behaviour and neurochemical systems at other developmental timepoints, and the mechanisms underlying these alterations remain unknown. Therefore, the goal of this thesis was two-fold: firstly, to investigate how the developmental stage of embryonic ethanol exposure differentially alters social behaviour and underlying neurochemistry, and second, to investigate novel mechanisms underlying embryonic ethanol-induced social deficits in adult zebrafish. Results presented here show both social behaviour and underlying neurochemistry are indeed impaired by ethanol in a developmental stage-dependent manner, however, the expression of ethanol-induced neurochemical dysfunction differed slightly depending on the age of observation. In adult zebrafish, abnormal social behaviour was accompanied by lower levels of whole brain dopamine, specifically when ethanol was administered at 10hpf, 16hpf and 24hpf, however, ethanol administered earlier (5hpf) and later (36hpf) had little to no effect. Additionally, abnormal social behaviour resulting from ethanol exposure at 24hpf was accompanied by lower levels of whole brain isotocin in adult zebrafish. Lastly, exposure to ethanol at 24hpf resulted in altered histone variant and neurochemical gene expression in adult zebrafish. These findings not only point to sensitive periods during early development but highlight potential new molecular candidates which may play an important role in the expression of embryonic ethanol-induced social deficits.
An Exploratory Study of Kindergarten Children’s Understandings About the Pedagogical and Social Nature of Kindergarten
Keywords: children's voices
full day learning
kindergarten
perception
play
social development

This study was conducted to investigate what children saw as the pedagogical and social purposes of their kindergarten experiences during the 2010-2011 school year when education in Ontario began a transition in the length and focus of kindergarten programs. In a large suburban region of Ontario, junior kindergarten (JK) children and senior kindergarten (SK) children (N=263) from kindergarten programs in 12 elementary schools were interviewed, with sampling from the new Full-Day Early Learning Kindergarten Program (FDELK) as well as from traditional kindergarten programs where it had not yet been implemented. Using a puppet technique, children were interviewed about the pedagogical aspects of kindergarten, such as what activities they liked and what they felt were important, and what their teachers did. They were also asked about the social nature of kindergarten, for example how they would solve social problems in kindergarten, including dealing with social conflicts involving themselves and other children. Children’s responses to interview questions demonstrated that they distinguished between ‘play’ and ‘work’ (academic skills such as pre-reading and numeracy), in the activities they favoured (play) and in those they saw as being important (work), and in what they perceived their teachers do (work). The study showed a relationship between children’s responses to the interview questions and higher receptive vocabulary and early reading ability scores. Children who mentioned work-related concepts and who reported multiple strategies in peer conflict situations had higher scores in vocabulary and early reading. A common theme across most children’s responses was the importance that they attached to learning rules and to following them. Children associated their teachers’ roles with behaviour guidance and rule enforcement in addition to leading instruction and distributing academic work. Few children mentioned that their teachers’ role was to play with them. There were slight demographic differences found in this study. SK children’s pedagogical perceptions were work- and rule-related, and social perceptions included more strategic solutions to conflict in comparison to JK children. English language learners (ELL) were more likely to mention play and work to be important, and their teachers’ role to be work-related compared to English first language children (EFL).
Quantum Parameter Estimation in the Laboratory
Keywords: Entanglement
Parameter estimation
Quantum metrology
Quantum optics
Super-resolution Imaging

In this thesis, I report on three projects which I have completed during my PhD. All of these projects are related to quantum parameter estimation.When simultaneously measuring all the parameters describing a unitary transformation, a decision needs to be made regarding the relative importance of these different parameters. In our first project, we show that the geometry of the group of unitaries in question can guide us toward a natural way of weighting these dif- ferent parameters. This allows us to transform the matrix Cram ́er-Rao inequality into a simple parameter-independent scalar inequality. We use this new inequality to calculate the best possible performances for a measurement of the parameters that describe a general SU(d) unitary and we find an optimal scalable family of quantum states which achieves this performance for SU(3) unitaries. In our second project, we experimentally create and characterize the tetrahedron state in the polarization of four photons. This entangled state is the optimal 4-photon state for measuring the three parameters describing a SU(2) polarization rotation. Interestingly, it possesses the same rotational symmetries as a tetrahedron, giving the state its name. We perform state tomography on our experimental state and measure a quantum state fidelity of F = (0.46 ± 0.02) with the ideal state. Our state nevertheless shares many qualitative features with the latter. Finally, in our last project, we propose a technique named SPLICE which allows us to beat “Rayleigh’s curse”—the inability to measure the separation between two incoherent point sources of light when said separation is below the imaging apparatus’ Rayleigh’s criterion. We test this technique in a proof of principle experiment in the laboratory and demonstrate its advantage over traditional methods.
An Assessment of How Targeted Health Policies were used to Influence Access to Radiation Therapy Services in Ontario, Canada between 1997 and 2017
Keywords: access to care
cancer services
Kingdon multiple streams framework
Ontario
policy
radiation therapy

This research provides a broad understanding of the impact of policy on access to radiation therapy (RT) in Ontario. A suite of policies implemented over 20 years address RT wait times and utilization aspects of access to care. The overarching research question was: “What was the impact of provincial and cancer centre level health policies on access to RT in Ontario between 1997 and 2017?” A case study design with multiple embedded units was used. The case was Cancer Care Ontario (CCO), and the embedded units included four representative regional cancer centres. Methods included a document review, longitudinal quantitative data collection, and key informant interviews. The theoretical underpinning was an extension of Kingdon’s Multiple Streams Framework, which collectively examines the problem, solutions and politics surrounding an issue. The access to RT problem evolved from a wait times issue to a utilization issue. Thirty-seven policies were identified and categorized as: (1) improving existing RT capacity, (2) system planning, (3) performance management, (4) human resources, and (5) building new RT capacities. During the first decade, policies were reactive in design, resulting in short-term wait time improvements. Policies in the second decade were more proactive and strategic, providing longer-term solutions. Building new cancer centres yielded the largest sustainable improvement to RT access. Restructuring CCO’s role to an oversight body, and changes to funding mechanisms were necessary system planning policies that also supported access improvement. Politics was highly influential across all levels, with negative media press, public pressure, local politics, and a healthy economy as factors. The Ontario cancer systems’ Regional Vice President role operated as an effective policy entrepreneur. They were able to adapt provincial policy to implement innovative access solutions locally. This longitudinal study provides useful insights into the evolution of Ontario’s cancer system as a more close-knit community of stakeholders, allowing the approach to policy implementation to mature from more reactive to proactive. Access to care continues to be a government priority, particularly as the world struggles through the COVID-19 pandemic. Learnings from this study can inform policy implementation decision-making surrounding access to RT and more broadly cancer and health services.
Linking Nuclear Mechanotransduction and Epigenetics in Morphogenesis
Keywords: development
epigenetics
limbbud
mechanotransduction
mouse
nucleus

Organ primordia shape is important for pattern formation and organ function. Morphogenesis generates forces through cellular rearrangements, proliferation, and shape change. These forces are felt by the cells of each tissue and are transmitted through them via the cytoskeleton. In addition to shaping tissues during development, emerging research suggests that mechanical forces play a role in gene expression. A traditional view of mechanotransduction is that extracellular and intracellular forces elicit a biochemical response, transmitting information to the nucleus. Intriguingly, evidencein vitro shows that nuclear strain can mechanically influence transcription by deforming the chromatin. Forces transmitted from the cytoskeleton to the nuclear lamina via the LINC complex, a direct mechanical connection, have the potential to efficiently couple morphogenesis with gene expression by pulling the genome to activate genome topology sensitive genes like the HoxA/HoxD clusters. To facilitate the investigation of potential nuclear mechanotransduction in vivo, I generated transgenic FRET‐based tension sensors. I utilized these sensors within the LINC complex protein, Nesprin2G, which links actin to SUN proteins, and the inner nuclear membrane protein NEMP1 which joins the nuclear lamina to chromatin to measure nuclear force transmission in living tissues. I tested invivo the responsiveness of each conditionally expressed sensor to physical and chemical manipulation of the mouse embryo. I helped develop software (FLIMvivo) to resolve challenges uniquely abundant with in vivo fluorescence lifetime imaging analysis. I found that force transmission to the nuclear interior indeed varies by tissue in the developing forelimb. Further, I used exogenous force via atomic force microscopy to modulate HoxA expression in live embryo forelimbs and have adapted a recently developed 3D stochastic reconstruction microscopy (3D‐STORM) OligoPaint approach to enable super resolution acquisition of chromatin topology at the single gene locus scale under differing cellular force regimes. These tools will be useful to measure the extent to which the genome and gene expression are influenced directly by the forces felt by cells not only during limb bud development, but also in other developmental processes, cancer, and disease.
Stress Corrosion Cracking and Pitting Corrosion of Carbon Steel in Ethanolic Environments
Keywords: DFT modelling
Ethanol
Pitting Corrosion
Stress Corrosion Cracking

Several studies have recently claimed that the Stress Corrosion Cracking (SCC) of carbon steel in ethanolic environments occurs by an anodic dissolution mechanism, but the exact mechanism is not well understood. In this research project, potentiostatic slow strain rate testing was conducted on SCC test specimens exposed to ethanolic environments prepared from pure dehydrated ethanol. Cracks of various types—intergranular and transgranular open cracks, and sharp closed transgranular cracks—were found by altering several testing parameters. The presence of chloride was found to be essential for crack initiation. SEM examination indicated that an “anodic” cracking mechanism, not necessarily slip-dissolution, was most likely operating at high elongations. Sharp closed transgranular cracks, with a maximum depth of 4 µm, were detected at elongations below 3% in ethanol solutions containing 2.5 mM LiCl. A focused ion beam was used to extract the tip of such a transgranular crack tip for analytical transmission electron microscopy using electron energy loss spectroscopy, which confirmed that the crack was in a ferrite grain. The sharp closed transgranular cracks seem to ally with the cracks observed in CO-CO2-H2O and anhydrous ammonia environments, which are proposed to grow by unique cleavage mechanisms. The possibility of embrittlement by carbon interstitials produced by ethanol electro-oxidation within the crack is discussed.The similarities of ethanol SCC and CO-CO2-H2O SCC prompted the investigation of the possibility of ethanol electrochemical oxidation into CO on ferrite (Fe) and cementite (Fe3C) surfaces. Density functional theory (DFT) computations on (110) surfaces reveal that the catalytic activity of Fe and Fe3C through the α dehydrogenation pathway can significantly reduce the energy barrier of electro-oxidation of ethanol and production of CO to 0.575 and 0.480 eV vs SHE, respectively. These first principles calculations indicate that at the anodic potentials applied during potentiostatic slow strain rate testing (SSRT), ethanol electro-oxidation to CO is thermodynamically viable on carbon steel, giving further credit to the involvement of cleavage type SCC of carbon steel in ethanolic environments.
Precise Larmor Time Measurements of a Tunneling Bose-Einstein Condensate
Keywords: Bose-Einstein Condensate
Cold atoms
Tunneling
Tunneling time
Weak Measurement

This dissertation presents precise tunneling time measurements of ultracold rubidium atoms tunneling through a narrow optical barrier. A pseudo-magnetic field localized to the barrier region causes the spins of the atoms to rotate while inside the barrier and the rotation is used to define a time of interaction. We observe that tunneling atoms spend less time interacting with the barrier as their energy is decreased below the barrier height. Furthermore, we find that atoms spend less time tunneling through higher barriers. Both observations confirm longstanding predictions about tunneling times. We also discover spin waves generated in the reflected cloud of atoms after collision with the barrier. Atomic interactions in the high-density regions of the reflected cloud drive additional spin rotations. We study this effect and find that it becomes the dominant contributor to spin rotations when the measurement of time spent inside the barrier is `strong'.
The Influence of Aquaculture on Marine Microbiota and Pathogen Communities in a British Columbia Coastal Ecosystem
Keywords: aquaculture
environmental dispersal
environmental DNA
environmental impacts
infectious disease
Pacific salmon

The productivity of wild-capture fisheries has long plateaued and global dependence on aquaculture is progressively increasing. Despite the perception that substituting wild caught seafood for domestic production benefits the conservation of wild populations through decreased fishing pressure, this is frequently not the case. Aquaculture can challenge the conservation of wild populations via the harvest of wild fish for feed, degradation of wild habitat, and by facilitating the spread of infectious disease. This thesis examines how aquaculture facilities influence microparasite transmission dynamics and the potential consequences for co-occurring wild species. I investigate these topics in coastal British Columbia, Canada, where wild Pacific salmon populations encounter open-net salmon farms along their migration routes. In chapter 2, I use seawater filtration and quantitative PCR (qPCR) to quantify the presence of DNA for 39 viral, bacterial, and eukaryotic microparasite species in the marine environment in relation to active Atlantic salmon farms. I show that the odds of encountering an infectious agent are 2.72 times higher at active salmon farms relative to inactive control sites. In chapter 3, I evaluate Atlantic salmon eDNA dispersal at 2m and 8m depths throughout 55 km of narrow migratory channels, in relation to four Atlantic salmon farms. I show that long distance dispersal (1.5 km – 3.9 km) occurs, and the spatial extent of environmental eDNA dispersal depends primarily on current velocity and depth. In chapter 4, I evaluate environmental microbe communities using deep amplicon sequencing to evaluate variation in community structure among 57 salmon farm tenures in relation to aquaculture activity, temperature, salinity, turbidity, and multiple scales of spatial predictors. The results from chapter 4 show that the effect of salmon farm activity on the marine microbiota was detectable but small relative to environmental variation and spatial structure although three bacterial Orders: Flavobacteriales, Rhodobacterales, and Alteromonadales, stood out as strongly positively correlated with salmon farm activity. The sustainability of aquaculture and the persistence of many wild populations will depend on our understanding of the local and regional influences of domestic reservoirs on microparasite transmission and our ability to develop integrated control measures to limit transmission among wild populations.
Cluster Structure for Mirkovic-Vilonen Cycles and Polytopes
Keywords: cluster algebras
Mirkovic-Vilonen

We look at the Mirkovic-Vilonen (MV) basis for semisimple Lie algebras and compare this to the associated cluster algebra to investigate the question of whether or not the cluster variables are in the MV basis. We begin with finding analogues of the cluster structure among MV cycles and MV polytopes. In particular, we show the exchange relations correspond to an equation involving MV polytopes. We extend a result of Baumann-Kamnitzer in relating valuations of an MV cycle and the dimension of homomorphism spaces of its associated preprojective algebra module. In doing so, we are able to give a partial result for an exchange relation involving MV cycles in low dimensions. In joint work with Dranowski and Kamnitzer, we present a way to calculate the fusion product of MV cycles in type A through a generalization of the Mirkovic-Vybornov isomorphism. Finally, we finish with examining the A3 example and show directly that the cluster variables in this case are in the MV basis.
Sqilxw Educator Rising: Sqilxw Educator Rising: Relationality as Methodology in a Social Work Abolitionist Framework
Keywords: 2 Spirit
Abolition
Harm Reduction
Indigenous Knowledge
Radical Relationality
Transgender

AbstractWai, iskwis (my name is), Percy Lezard. Sqilxw ways, personal introductions come before any other words. I am outma sqilxw I was born into a family of sexʷwrmin̓ (firekeepers). This research demonstrates how I as a sqilxw stamya? educator have been able to survive and thrive, through my sqilxw identity and Indigenous knowledges, in mainstream post-secondary education institutions. I have used myself as both the subject and researcher within the social context of post-secondary social work settings, with an insider’s vantage point to chronicle my own pedagogical transition, using the qualitative methodology of relationality. Through my interpretations and reflections about two post-secondary programs, I use comparison to highlight the complexities of their strengths and inadequacies. This work includes my account as an Indigenous scholar working within a college program grounded in feminist theory, and a university department grounded in an anti-oppression/anti-racism framework. It explores experiences of anti-Indigenous racism, cis-sexism, pushback for my position of solidarity with Black liberation, and oppressions within a disability justice framework. Using the methodology of relationality, I share the experiences I have encountered and the problems I have faced, to facilitate an understanding of the processes of transition. As the genre of qualitative research brings the reader closer to the subculture studied through the experiences of the author, my work serves to provide an evaluation and insights into the cultures of these two learning environments. Data gathering consisted of a reflexive journal, my personal calendar, faculty agendas, staff memos, and reflective analysis. As well, in each of the institutions, I was able to gather support and insight through ceremony and interactions with Knowledge Keepers and Elders. In this way, I was able to reflect upon teachings and to apply Indigenous knowledges to my work. These research tools were used to capture the experiences of my transition. The results of this study were expressed in a personal narrative that comprises of Section 1: Situation, Owing, Questioning. Section 2: How did I come to formulating an Abolitionist Social Work Framework? Section 3: History of Social Work Harms. Section 4: Alternatives Section 5: Vision and closing remarks.