VictorJuiz/thesis huggingface dataset:
Teachers' and Principals' Perceptions of Contexts and Conditions that Maintain Bullying in Elementary Schools

ABSTRACT Although extensive research has been conducted on bullying, few studies have explored factors that elicit, impact, and maintain the dynamics of bullying from the perspectives of teachers and principals. The purpose of this study was to understand the complex nature of bullying through exploring the ecological risk factors that allow this alarming phenomenon to flourish. The influence of factors at the microsystem, mesosystem, exosystem, and macrosystem on the dynamic interaction between the bully and the victim is explained. Another goal of this research was to capture the complexity and multidimensionality of the teacher’s role in bullying prevention and intervention. The study offers the first comprehensive analysis of the ecological and contextual variables that interact to provide fertile grounds for bullying. Detailed information about principals’ and teachers’ perceptions of bullying experiences was gathered through 8 in-depth focus groups for teachers and 10 interviews with principals. Qualitative analyses of the data led to the emergence of overarching themes and related subthemes. Bronfenbrenner’s ecological model (1979 ) was used to provide a conceptual and comprehensive framework that addressed the multifaceted variables. The finding indicated that a complex interrelation of variables was found to be central to victimization. The incidence of bullying was found to be directly influenced by individual traits as well as all the other ecological systems. Among the most salient findings was the influence of the peer ecology on bullying as a group phenomenon. The etiology of bullying as a manifestation of much deeper problems at the bully level was among the new findings. The impact of video games and television reality shows on bullying behaviour was also identified. The findings emphasized the significance of the teacher personality, positive teacher-student relationship, empathy, and training in classroom management for efficacy in addressing bullying prevention and intervention. Finally, the study offers recommendations for teacher training institutions.

Keywords: bullying in Schools
violence in schools
teachers' perceptions of bullying
Advisor: Gillis, Roy
Genetic Determinants of Psoriatic Arthritis

Psoriatic Arthritis (PsA) is an inflammatory arthritis associated with psoriasis that leads to progressive joint damage. Genetic variants in the Major Histocompatibility Complex (MHC) region on human chromosome 6p, especially Human Leucocyte Antigen (HLA), are the most important genetic risk variants associated with susceptibility to PsA. I aimed to investigate the heritability of PsA and to determine the association between HLA polymorphisms with susceptibility and severity of PsA. I first validated the new CASPAR classification criteria for PsA in patients in with both early and established disease. Subsequently, I demonstrated that PsA as defined by the CASPAR criteria has a high recurrence risk ratio. In a large case-control and family-based association study, I demonstrated that the class I HLA alleles, HLA-C*12/B*38, -B*27 and -C*06/B*57 are associated with increased susceptibility to PsA. HLA class I molecules biologically interact with Killer-cell Immunoglobulin-like Receptors (KIR) on Natural Killer (NK) to influence immune response. I demonstrated that KIR2DS2 and HLA C group 2 and HLA-B Bw4 were associated with PsA susceptibility. Further analyses of PsA cases with Type II psoriasis and with dactylitis suggested that HLA-C*02, -B*27, -B*38 and KIR2DS2 may be markers of musculoskeletal manifestations of PsA. Furthermore, using longitudinal data, I demonstrated that HLA-B*39, -B*27, -A*02 and KIR3DS1 are associated with peripheral joint damage progression whereas the alleles –DQB1*0604, -C*04 and –B*60 are associated with less damage progression. HLA-C*02, -C*12, -DQB1*0609 and KIR2DS1 are associated with higher risk of sacroiliitis, and HLA-B*27 with syndesmophytes. HLA-A*29 was associated with reduced risk of development of both sacroiliitis and syndesmophytes. These studies indicate that HLA alleles and KIR genes are important in PsA susceptibility and severity and suggest that CD8+ T cells and NK cells that modulate the innate and adaptive immune response play an important role in the susceptibility and severity of PsA.

Keywords: genetic epidemiology
spondyloarthritis
psoriasis
prognosis
Advisor: Gladman, Dafna D.
On the Clinical Applicability and Translation of Genetic Discoveries in Schizophrenia

Schizophrenia is a genetically complex neuropsychiatric disease. Myths and uncertainty about aetiology, and concerns about familial recurrence, may contribute to the significant stigma and burden on families. There has recently been concrete progress in understanding individual genetic causes of schizophrenia, which are now known to extend beyond 22q11.2 microdeletions to include other large rare copy number variations. However, there are limited data on issues germane to the translation of these genetic discoveries into clinical practice. The aim of this thesis was to evaluate the contemporary clinical applicability of genetic testing and genetic counselling in schizophrenia. First, general genetic counselling was provided to both adults with schizophrenia without individually relevant genetic test results and their family members. Pre-counselling, there was evidence of widespread misconceptions about schizophrenia aetiology and familial recurrence risks, which were associated with considerable psychological distress. Post-counselling, the myriad significant lasting benefits of genetic counselling included reductions in stigma. The results provided initial evidence of need for, and efficacy of, genetic counselling for schizophrenia. A first ever study was then conducted of the impact of providing a specific aetiological explanation for schizophrenia. Affected individuals and family members were found to value a molecular genetic diagnosis of a 22q11.2 microdeletion for its ability to explain the presence of stigmatized neuropsychiatric conditions. An investigation of transmission patterns and reproductive fitness associated with 22q11.2 microdeletions provided novel insights into the evolutionary biology and clinical correlates of this structural rearrangement. The results demonstrated the scientific and clinical benefits of identifying a genetic subtype of schizophrenia. Last, high resolution genome-wide microarrays were used to investigate rare copy number variations in a prospectively recruited community-based schizophrenia cohort. Clinically significant variants were greatly enriched in schizophrenia, even with 22q11.2 microdeletions a priori excluded. The collective prevalence of these genetic variants in a single community catchment area was high, approaching that seen in autism, where clinical microarray testing is now a first-tier diagnostic test. Collectively, the findings of these pioneering studies suggest a role for genetic testing and genetic counselling in the contemporary management of schizophrenia.

Keywords: copy number variation
genetic counselling
genetic testing
schizophrenia
Advisor: Bassett, Anne
Towards an Understanding of Dissolved Organic Matter Molecular Composition and Reactivity in the Environment

Dissolved organic matter (DOM), one of the most complex naturally occurring mixtures, plays a central role in the biogeochemistry and the photochemistry of natural waters. A complete understanding of the environmental role of DOM will come only from the elucidation of the relationship between its structure and function. This thesis presents new work on the separation, characterization, and reactivity of DOM in rainwater, freshwater, and seawater. A new separation technique based on counterbalance capillary electrophoresis was developed for the separation of Suwannee River NOM. A comparative study of the organic content of rainwater was accomplished using nuclear magnetic resonance (NMR) with spectral database matching ,Fourier transform ion cyclotron mass spectrometry (FT-ICR-MS), and comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS). Three complementary, non-overlapping datasets identified of over 400 compounds. Analysis of the FT-ICR-MS data using van Krevelen diagrams and the carbon oxidation state showed variation in the elemental composition and molecular size. Over 50% of the compounds identified in this study were known components of secondary organic aerosol (SOA) and volatile organic carbon (VOCs). Dissolved organic matter (DOM) plays a central role in the photochemistry of natural waters through the production of reactive oxygen species and the triplet excited state of DOM (3DOM*). These reactive species are central to the reactivity, transport, and fate of both natural and anthropogenic chemicals in the environment. Laser flash photolysis (LFP) was used to demonstrate that particulate organic matter (POM) generates a triplet excited state species (3POM*). LFP of seawater from the Pacific Ocean and the Bermuda Atlantic Time Series Station detected similar excited state species from surface to 4535m. Metal speciation has been implicated in the photochemistry of natural waters. Copper immobilized metal affinity chromatography (IMAC) of seawater and freshwater isolated a low and a high affinity fraction that generated excited state transients. Excitation-emission matrix spectroscopy showed that while the seawater fractions were autochthonous, freshwater fractions enriched in chromophoric DOM (CDOM), were allochthonous. The discovery of these different classes of compounds in freshwater and seawater has important implications both for the mineralization of DOM and the removal of xenobiotics in the aquatic environment.

Keywords: Dissolved organic matter
Photochemistry
NMR
FT-ICR-MS
GCxGC-TOFMS
Advisor: Simpson, Andre
Supporting the Use of Causally Related Functions in Biomimetic Design

Biomimetic design uses biological analogies to produce innovative engineering solutions. However, designers face challenges in identifying useful biological analogies and correctly applying the analogies identified to design solutions. To overcome these challenges, this thesis proposes the use of causally related functions in biomimetic design. Causally related functions describe how a desired function is enabled by another function. To support the use of causally related functions, a set of tools was developed. First, the causal relation template and mapping techniques (one-to-one mapping instructions and problem-independent scenario mapping) were devised to assist designers to identify and apply causally related functions from descriptions of biological phenomena. In pen-and-paper experiments with senior undergraduate engineering students, the causal relation template, if used correctly, facilitated the development of design concepts that were analogous to biological phenomena provided as sources of analogy. In addition, the mapping techniques reduced the percentage of participants who made non-analogous associations from biological phenomena to develop design concepts. Another tool developed was the causal relation retrieval method. The method uses syntactic information in natural language sentences to explicitly identify causally related functions. A modified verbal protocol study with graduate engineering students revealed that the retrieval method increased the likelihood of locating biological phenomena relevant to given design problems compared to a single verb-keyword search method. Also, the search matches located with the retrieval method were more likely to facilitate functional association to develop design concepts. These results demonstrate that the knowledge structure of causally related functions can support both the identification of relevant biological phenomena in natural language text and use of analogical reasoning between the biological phenomena and design solutions. The causal relation template and mapping strategies developed contribute to the field of biomimetic design as training methods for designers; and the causal relation retrieval method could serve a technique to bridge the gap between the natural language approach and the modeling approach to biomimetic design.

Keywords: Biomimetic design
Design cognition
Design methodology
Conceptual design
Advisor: Shu, Lily H.
Matrix Mechanical and Biochemical Regulation of Multipotent Stromal Cell Osteogenesis

Biochemical and mechanical properties of the extracellular matrix (ECM) are known to independently influence cell function. Given the complexity of cellular responses, I hypothesized that the integration of multiple matrix factors as opposed to their individual contribution is key to understanding and controlling cell function. The objective of this thesis was to systematically investigate matrix biochemical and mechanical regulation of multipotent stromal cell (MSC) osteogenesis. First, I demonstrated that substrate stiffness-dependent MSC spreading, proliferation and osteogenic response were differentially regulated by matrix protein type (collagen I vs. fibronectin) and concentration. Second, I developed and characterized a matrix microarray platform that enabled the efficient screening of multiple matrix-derived cues (substrate stiffness, ECM type and density). I implemented the matrix microarray platform together with parametric regression models to elucidate novel matrix interactions in directing mouse MSC osteogenic and adipogenic differentiation. Third, I extended the screening study to examine matrix-dependent human MSC osteogenesis. Non-parametric regression models were used to provide a nuanced description of the multi-factorial matrix regulation in MSC osteogenesis. The response surfaces revealed a biphasic relationship between osteogenesis and substrate stiffness, with the exact location and magnitude of the optimum contingent on matrix composition. Guided by the screening results and perturbation to key cytoskeletal regulators, I identified a novel pathway involving Cdc42 in matrix mechanical and biochemical regulation of MSC osteogenesis. Surprisingly, Cdc42 mediated stiffness-dependent MSC osteogenesis independent of ROCK, suggestive of a contractility-independent mechanism in matrix rigidity signal transduction. In summary, the integration of cell-based arrays and statistical modeling has enabled the systematic investigation of complex cell-matrix interactions. This generalizable approach is readily adaptable to other cellular contexts, complementing hypothesis-driven strategies to facilitate non-intuitive mechanistic discovery. Moreover, the improved understanding of matrix-dependent MSC function also has practical relevance to the development of biomaterials for tissue engineering applications.

Keywords: mesenchymal stromal cell
substrate stiffness
osteogenesis
Advisor: Simmons, Craig Alexander
Regulation of P-glycoprotein by Nuclear Receptors at the Blood-brain Barrier: Relevance to Human Immunodeficiency Virus-1 Pharmacotherapy

ATP-binding cassette membrane-associated drug efflux transporters expressed at the blood-brain barrier (BBB) are important determinants of drug disposition in the central nervous system. Targeting the regulatory pathways that govern the expression of drug transporters, such as P-glycoprotein (P-gp) could provide novel approaches to selectively alter drug permeability in the brain. Pregnane X Receptor (PXR) and Constitutive Androstane Receptor (CAR) are ligand-activated nuclear receptors which regulate the gene expression of several drug transporters, including P-gp. Currently, knowledge on their significance at the BBB is limited. The overall goal of this Ph.D. thesis was to examine the role of these two nuclear receptors in the regulation of P-gp functional expression in brain microvessel endothelial cells, an important compartment constituting the BBB, and in a mouse model. We demonstrated hPXR and hCAR protein expression in two human brain microvessel endothelial cell culture models (i.e., hCMEC/D3 and primary cultures of human brain-derived microvascular endothelial cells). We further showed the in vitro role of hPXR and hCAR in regulating P-gp functional expression in the hCMEC/D3 cells. In addition, results obtained from Luciferase reporter gene assays demonstrated that several antiretroviral drugs currently used in the clinic are ligands for hPXR (i.e., amprenavir, atazanavir, darunavir, efavirenz, ritonavir and lopinavir) and hCAR (i.e., abacavir, efavirenz and nevirapine). These drugs significantly induced P-gp functional expression in hCMEC/D3 cells at clinical plasma concentrations. Applying quantitative intracerebral microdialysis in CD-1 mice, we observed that P-gp induction mediated by a mouse PXR ligand/P-gp inducer (i.e., dexamethasone) at the BBB significantly decreased the ratios of quinidine (an established P-gp substrate) concentrations in brain extracellular fluid to unbound plasma concentrations at steady state (Kp,uu,ECF/Plasma) when compared to vehicle-treated animals. Taken together, our data provide evidence that hPXR and hCAR could be potential xenobiotic targets for the regulation of P-gp at the BBB. This work will guide future development of novel pharmacotherapy that could target these receptors to alter drug transporters functional expression at the BBB, resulting in either enhanced CNS drug efficacy or reduced drug-associated neurotoxicity.

Advisor: Bendayan, Reina
Not "Just Staying": How Health and Development Programming is Reshaping the Past, Present and Future for Rural Youth in Malawi

Drawing on ethnographic and visual anthropological data, this dissertation explores the anticipated and unanticipated effects of youth-targeted health and development programmes in rural Malawi. Contemporary development programmes are anticipatory in nature: they are focused on managing health, behaviour, education and social relations today in ways that are believed to open opportunities for some distant and better future. Working with rural youth who “just stay,” an idiom youth use to describe their “failure” to make progress towards desired futures, I show how discourses and ideals espoused in anticipatory programmes including human rights, education, gender and love are slippery concepts. As they percolate through this particular social, political, historical and demographic context and into the imaginaries of young people, these discourses often become something new and unexpected. In particular I show how: i) a discursive elision occurs between the rights discourse and other markers of modernity and youth take up their “right” to wear modern clothing and drink commercial alcohol, ii) selfish behaviours including alcoholism and womanising surface in boys’ self-constructions as innate tendencies rather than part of a socially produced and constantly shifting construction of masculinity, iii) audit cultures, critical to the operation of anticipatory programmes, reduce gender equality to something “countable,” which, in turn, alters programme activities, leads to performances by participants and filters into youth subjectivities, and iv) discourses on modern and “healthy” loves, free from HIV/AIDS, lead to re-arrangements in romantic relations and friendships that provide new and positive opportunities for women not always available in customary marriages. By privileging the future over the present and the past, programmes overlook numerous structural barriers to improving the lives of the youth who “just stay.” I argue that the unanticipated effects of these programmes constitute and give rise to several invisible forms of violence. On the other hand, however, some effects are generative of new and positive subjectivities and relationships that are egregiously overlooked by programmes. This ignorance prevents programmes from building upon positive effects to generate desired change and sometimes even undermines their own stated goals.

Keywords: Health and Development Programming
HIV/AIDS
Malawi
Africa
Youth
Anticipation
Human Rights
Gender
Advisor: Wardlow, Holly
Sellen, Daniel
The Fabrication of Direct Oxidation Solid Oxide Fuel Cell Anodes Using Atmospheric Plasma Spraying

Solid oxide fuel cells (SOFCs) that operate directly on hydrocarbon fuels eliminate the requirement for costly and complex external reforming systems. Atmospheric plasma spraying (APS) is an established manufacturing method that offers the potential to fabricate direct oxidation SOFC anodes in a single step, instead of the multiple steps currently required. Manufacturing by APS also allows the use of metal supports, which improve thermal shock resistance, allow rapid cell heat-up, and reduce total cost. In this study, direct oxidation SOFC anodes based on Cu and samaria-doped ceria (SDC) in combination with Co and/or Ni were investigated for their stability and performance in H2 and CH4 when plasma sprayed on ferritic stainless steel supports. Several different APS techniques were investigated. Two of these techniques were hybrid methods involving a combination of dry powder plasma spray and suspension plasma spray (SPS) processes. These techniques were proposed to help balance the degree of melting of the lower melting temperature oxides of the metals Cu, Co, and Ni with that of the higher melting temperature SDC. The use of a single suspension containing all of the anode component feedstocks was also investigated. Multi-component aqueous suspensions of CuO, Co3O4, and NiO were developed with or without the addition of carbon black and SDC. It was found that the use of a hybrid plasma spray technique can help to improve deposition efficiency (D.E.) and enhance partial melting of the low melting temperature feedstocks. However, plasma spraying all of the components in a single suspension can lead to more homogeneous mixing and greater resistance to metal coarsening at SOFC operating temperatures. In electrochemical tests of plasma-sprayed metal-supported cells containing these anodes, peak power densities as high as 0.6 W/cm2 were achieved at 750 deg C in humidified H2. In CH4, power density was limited by the activity of the anodes. Stability in CH4 was poor because of oxidation of the metal support and enhanced coking behaviour resulting from interactions between Fe in the support and Co and Ni in the anodes. When separated from the supports, the anodes demonstrated very low coking rates in thermogravimetric analysis experiments in CH4.

Keywords: Solid Oxide Fuel Cell
Anode
Direct Oxidation
Plasma Spray
Copper
Ceria
Advisor: Kesler, Olivera