VictorJuiz/thesis huggingface dataset:
Job Stress, Job Satisfaction and Intention to Leave Among New Nurses

The difficulties new nurses experience when first entering acute care work environments have been recognized since Kramer’s seminal work in the 1970s. Despite the implementation of interventions designed to help ease the transition, the literature continues to report that new graduates undergo stress when beginning their careers as nurses. The purpose of this study was to examine the effects of perceived demands, control, social support and self-efficacy on the job stress, job satisfaction and intention to leave of new nurses. The conceptual framework used in the study was Karasek’s (1979) Job Demands-Control-Support (JDC-S) model. This model posits that job demands increase employee stress, but that increasing control can alleviate the negative effects of high demands. Social support and self-efficacy were included in this study as potential moderators of the relationships between demands and control and the outcome variables. This was an exploratory study that utilized a cross-sectional survey was used to gather data. Surveys were mailed to the homes of new nurses working in acute care hospitals across Ontario, Canada. Data were received from 232 new nurses, a response rate of 23.8%. Nurses in the sample had an average of 18.2 months of experience. Data were analyzed using separate hierarchical regression models for each dependent variable. The results showed that the main effects of job demands, social support and self-efficacy provided partial support for the JDC-S model when examining job stress, job satisfaction and intention to leave the job. Only self-efficacy was significantly related to intention to leave the profession. There was no evidence of moderating effects of social support or self-efficacy. An understanding of factors in the work environment that influence new nurses may assist in supporting them during the transition. By exploring the effects of demands, control, social support and self-efficacy on new graduates’ job stress, job satisfaction and intention to leave, this study may provide direction to nursing leaders who are working new nurses in acute care.

Keywords: job stress
new nurses
Advisor: Hall, Linda McGillis
Pleasure in the Daily Lives of People Living with Advanced Dementia in a Long-term Care Facility: A Multiple Case Study Approach

According to the Canadian Study of Health and Aging most of the 12,630 Canadians living with advanced dementia reside in long-term care facilities. This number is rising due to an aging population. The purpose of this study is to address an identified gap in our knowledge about what creates pleasure in people with advanced dementia, through first understanding family caregivers’ ways of eliciting and interpreting positive emotions in their relatives and then having the personal support worker (PSW) try these same approaches to see if similar responses are achieved. This study used a qualitative multiple case study design. Data collection methods included digitally recorded interviews and video-recorded observations of interactions between residents and caregivers. A case is defined as a resident with moderately to severely advanced dementia. Each case had two informants: a family member and a PSW meeting inclusion criterion. There were seven cases. The resident participants spanned a range from moderately advanced to severely advanced dementia. Data analysis used both inductive and deductive coding with sensitizing concepts of selfhood, personhood, continuity of personality and well-being. The results of this study centred on four main themes related to the research questions about the sources and indicators of pleasure and the potential for PSWs to replicate what family members did with residents. Some sources of pleasure were lost, some were maintained and new ones developed post-illness in all of the residents. Both family members and PSWs were knowledgeable about sources and indicators of pleasure for the people with dementia they were involved with. The analysis demonstrated that for individuals with very advanced dementia, the concept of pleasure or enjoyment is not applicable. The family members of the two residents with very advanced dementia used music, touch and sweets to elicit a pleasurable response but the resident did not display indicators of pleasure in response; instead, the residents responded with grasping or other responses which require further research to understand fully. Future research should build upon these findings in order to further understand the concept of positive affect: pleasure, interest and enjoyment in people with advanced dementia of the Alzheimer type.

Keywords: Alzheimer's disease
Quality of life
Nursing
Qualitative methods
Case study
Positive affect
Long-term care
Dementia
Pleasure
Advisor: Pringle, Dorothy
Mechanisms of Fatty Acid Induced Decrease in β-cell Function

An important mechanism involved in the pathogenesis of type 2 diabetes is elevation of plasma free fatty acids which induce insulin resistance and may impair both β-cell function and mass (β-cell lipotoxicity). The objective of my thesis was to investigate the role of oxidative stress in β-cell lipotoxicity, using in vivo, ex vivo, and in vitro models. I used in vivo models of 48h i.v. oleate or olive oil infusion in Wistar rats followed by hyperglycemic clamps, or islet secretion studies ex vivo, and in vitro models of 48h exposure to oleate in isolated islets. My first study showed that 48h oleate infusion decreased the insulin response to a hyperglycemic clamp, an effect prevented by coinfusion of the antioxidants N-acetylcysteine and taurine. Similar to the findings in vivo, 48h infusion of oleate decreased glucose stimulated insulin secretion (GSIS) ex vivo, and induced oxidative stress in isolated islets, effects prevented by coinfusion of the antioxidants N-acetylcysteine, taurine, or tempol. Islets exposed to oleate or palmitate showed a decreased insulin response to high glucose and increased levels of oxidative stress, effects prevented by taurine. Therefore, my data are the first demonstration that oxidative stress plays a role in the decrease in β-cell secretory function induced by prolonged exposure to FFA, in vitro and in vivo. My second study addressed downstream effects of oxidative stress involving inflammation. A 48h infusion of oleate or olive oil decreased β-cell function during a hyperglycemic clamp, an effect prevented by coinfusion of the IKKβ inhibitor salicylate. GSIS in isolated islets was impaired by olive oil or oleate and restored by salicylate. These results suggest a potential role for both oxidative stress and inflammation in lipid-induced β-cell dysfunction. My third study addressed downstream effects of oxidative stress involving β-cell insulin signalling. A 48h infusion of oleate or olive oil decreased β-cell function during a hyperglycemic clamp, an effect prevented by coinfusion of the tyrosine phosphatase inhibitor bisperoxovanadate. GSIS in isolated islets was impaired by olive oil or oleate and restored by bisperoxovanadate, suggesting a role of FFA in decreasing β-cell function by induction of β-cell insulin resistance.

Keywords: Type 2 Diabetes
Oxidative Stress
Free Fatty Acids
Lipotoxicity
Beta-cell
Advisor: Giacca, Adria
Return to Work with Cardiac Illness: A Qualitative Exploration from the Workplace

Objectives: Research literature points to a range of “factors” that are associated with return to work outcomes but little understanding of the experience of workers, the strategies used to adapt, how work shapes and influences adjustment, and the trajectories that describe their return to work experience. The aim of this qualitative, workplace-based study was to characterize workers readaptation to the workplace and develop a substantive framework for return to work following disabling cardiac illness. Methods: The study used a concurrent, nested, mixed methods approach, using grounded theory to inform the sampling and analysis framework. Participant workers were 12 males having suffered occupational disability owing to cardiac illness and returning to work at a large auto manufacturing plant. Participants were purposefully sampled for a range of disease and disability experiences as well as a range of work roles in the plant. Data were derived from semi-structured in-depth interviews, standardized questionnaire measures of health-related quality of life and work limitations, observations within the plant, and extensive field notes and memos. Longitudinal information was obtained through follow-up interviews over a two to ten month period. Results: Participants had a range of illness impacts and representations and fulfilled diverse roles in the plant including assembly jobs and trade work. Thematic analysis revealed that participants used adaptive strategies including changing mindset in relation to work, building physical capacity and efficiency, managing relationships and work schedules, and using supports in the plant. Thematic analysis highlighted the importance of the nature of work, the quality of work relationships, organizational practices around accommodation and supports in the workplace including occupational health support. Conclusions: Worker adaptation following disabling cardiac illness involved a process of self-regulation including elements of illness and work representations, deployment of adaptive strategies to compensate for ongoing impairments, self-monitoring, goal setting and adaptive selection of work activities. Work demands, relationships and structures provide a range of possibility for self-regulation and quality of life. Implications for practice for work and health researchers and professionals as well as potential linkages to theory are discussed.

Keywords: cardiovascular disease
disability
work
adaptation
rehabilitation
coping
Advisor: Thomas, Scott
Optimizing the Pharmacology of Periconceptional and Prenatal Multivitamin Supplementation

It is highly recommended for women to take multivitamin/mineral supplements during the periconceptional and prenatal periods. Studies have confirmed that taking prenatal multivitamins prevents maternal iron deficiency anemia, and reduces the risk for neural tube defects (NTDs). To date, research aimed at optimizing the use of multivitamins before and during pregnancy has been minimal. My thesis focused on two challenges of periconceptional and prenatal multivitamin supplementation. The first challenge was gastrointestinal (GI) adverse events such as nausea and constipation which may be attributed to iron content and tablet size. Pregnant women are highly susceptible to GI adverse events since 80% experience nausea and vomiting of pregnancy. A prospective, randomized, controlled, open-label study was conducted to investigate whether a low-iron, small-tablet prenatal multivitamin can reduce GI adverse events, and improve supplement tolerability and adherence, relative to a high-iron, small-tablet prenatal multivitamin. We determined that low iron dose did not produce a significant difference, while small tablet size could be considered an important factor. Moreover, our results confirmed that adherence was poor in pregnant women. We were prompted to identify determinants which could predict adherence to prenatal multivitamins. Our retrospective study determined that predictors of adherence are rooted in women’s prior experiences with multivitamin use. The second challenge we addressed was achieving adequate blood folate concentrations for prevention of NTDs. If adherence is poor, standard dosing of 0.4-1 mg folic acid may not produce the blood folate concentrations needed in women prior to conception. We investigated the pharmacokinetics of 5 mg folic acid. Our prospective, parallel, open-labeled study, comparing a single dose of 5 mg to 1.1 mg folic acid, confirmed that folic acid follows linear (proportional) pharmacokinetics. However, our prospective, randomized, controlled, open-labeled, multiple-dose study determined that repeated use of folic acid at these 2 doses followed non-linear pharmacokinetics. Nevertheless, our data confirmed that 5 mg folic acid can produce higher blood folate concentrations, with a faster rate, which can counter the effect of poor adherence. In conclusion, optimal use of prenatal multivitamins requires improvements in supplement tolerability, adherence, and pharmacokinetics which depend on supplement formulations, and individualized assessment and counseling.

Keywords: folic acid
multivitamin supplementation
pregnancy
pharmacokinetics
Advisor: Koren, Gideon
Civic Capital and the Dynamics of Intermunicipal Cooperation for Regional Economic Development

This thesis concentrates on the interplay of structural and societal factors in the development of regional governance though a comparative study of two Canadian (Toronto and Waterloo) and two German (Frankfurt and the Rhein-Neckar) city regions. It was inspired by the tendency, in both scholarship and practice, to turn to formal institutional reform to solve problems of regional coordination. Debates of new regionalism advocate a role for governance solutions, which encourage a broader spectrum of actors to engage in the policy process. However, the emphasis in most jurisdictions has remained on formal, institutionalized structures, imposed by senior levels of government. As a result, the construction and potential for bottom-up and collectively negotiated regional solutions are typically under-explored. This thesis builds a case for intermunicipal cooperation as an alternative approach to regional coordination, uniting the participatory concept of regional governance with functional flexibility of cooperative networks. It analyses what factors affect the emergence of these networks for governance in three areas of regional economic development: regional marketing, cultural policy and regional transportation. It argues that while regional structural, institutional and contextual variables are useful in understanding the emergence of development partnerships, they tend to have different effects in different cases. The thesis formulates and applies an innovative concept – civic capital – to capture the dynamics of building and sustaining regional governance networks. It is both a critique and extension of social capital approaches to regional development. Using the four cases the thesis argues that, where civic capital is high intermunicipal cooperation is more likely regardless of institutional and structural contexts. Consequently, the thesis makes a theoretical contribution to both literature on intermunicipal cooperation and broader debates on the dynamics of regional governance, development and social networks.

Keywords: regional governance
economic development
intergovernmental relations
local government
Advisor: Wolfe, David A.
Eurasian Middle and Late Miocene Hominoid Paleobiogeography and the Geographic Origins of the Homininae

The origin and diversification of great apes and humans is among the most researched and debated series of events in the evolutionary history of the Primates. A fundamental part of understanding these events involves reconstructing paleoenvironmental and paleogeographic patterns in the Eurasian Miocene; a time period and geographic expanse rich in evidence of lineage origins and dispersals of numerous mammalian lineages, including apes. Traditionally, the geographic origin of the African ape and human lineage is considered to have occurred in Africa, however, an alternative hypothesis favouring a Eurasian origin has been proposed. This hypothesis suggests that that after an initial dispersal from Africa to Eurasia at ~17Ma and subsequent radiation from Spain to China, fossil apes disperse back to Africa at least once and found the African ape and human lineage in the late Miocene. The purpose of this study is to test the Eurasian origin hypothesis through the analysis of spatial and temporal patterns of distribution, in situ evolution, interprovincial and intercontinental dispersals of Eurasian terrestrial mammals in response to environmental factors. Using the NOW and Paleobiology databases, together with data collected through survey and excavation of middle and late Miocene vertebrate localities in Hungary and Romania, taphonomic bias and sampling completeness of Eurasian faunas are assessed. Previous bioprovincial zonations of Europe and Western Asia are evaluated and modified based on statistical analysis of Eurasian faunas and consideration of geophysical, climatic and eustatic events. Within these bioprovinces, occurrences of in situ evolution and directionality of dispersals of land mammals are used as a framework to address and evaluate these same processes in Eurasian apes. The results of this analysis support previous hypotheses regarding first occurrences and phyletic relations among Eurasian apes and propose new ideas regarding the relations of these taxa to previously known and newly discovered late Miocene African apes. Together with analysis of environmental data, Eurasian mammals support the hypothesis that the descendant of a Eurasian ape dispersed to Africa in the early late Miocene (top of MN7/8 or base of MN9), however the question of whether this taxon founded the African ape and human lineage remains equivocal.

Keywords: Paleoanthropology
Miocene
Hominoid
Paleobiogeography
Advisor: Begun, David
The Morphology of Local Galaxies and the Basis of the Hubble Sequence

The goal of galaxy classification is to understand the physical basis for the wide range in shapes and structures exhibited by galaxies in the local and high redshift universe. We present a catalog of visually classified galaxies from the Sloan Digital Sky Survey with detailed morphological classifications including bars, rings, lenses, tails, warps, dustlanes, arm flocculence and multiplicity (so called ’fine structure’). This thesis explores the importance of galaxy morphology by probing its relationship to physical properties. Our analysis includes an investigation of correlations between fine structures and AGN activity. This sample defines a comprehensive local galaxy sample which we use to study the low redshift universe both qualitatively and quantitatively. We find the stellar mass appears to be a defining characteristic of a galaxy. The break in most correlations of physical properties with morphology is due to a lack of late type, massive disk galaxies. Our analysis of the size-mass relations of galaxies as a function of morphology (T-Type) has revealed many interesting connections. We find the size-mass relation of Sa, Sab, Sb, and Sbc galaxies bifurcates into two families of objects as one moves down the sequence such that the high concentration branch exhibits a similar slope to low concentration early type (E) galaxies suggesting a closer than expected physical (possibly evolutionary) connection between the two populations. We find bar fraction is bimodal with respect to mass (at 3 x 10^10 M) and color (at g - r ∼ 0.55). The dependence is seen to intimately depend on central concentration such that objects below the transition mass with low concentrations have a higher bar fraction than objects above the transition mass which have high bar fractions for high concentration systems. In addition we find the presence of an AGN alters the behavior and abundance of barred/ringed galaxies in the high mass peak such that the bar/ring fractions increase with mass in nonactive galaxies whereas they decrease with mass in active galaxies. AGN fractions are also decreasing in the same mass range possibly implying a positive correlation between fine structure and ring formation.

Keywords: Galaxy Morphology
Bar
Ring
Lens
AGN
Bimodality
Advisor: Abraham, Roberto
The Role of CCL5/CCR5 Signal Transduction in T cell Function and Breast Cancer

Chemokines are responsible for directing leukocyte migration and triggering firm arrest by activating integrins on leukocytes. It is now apparent that chemokines have critical biological roles beyond chemo-attraction. Throughout this thesis, I describe the importance of the CCL5/CCR5 axis in the context of the immune response and cancer biology. Specifically, CCL5 invokes dose-dependent distinct signalling events downstream of CCR5 activation in T cells. I show that nM concentrations of CCL5 mediate CD4+ T cell migration that is partially dependent on mTOR activation. CCL5 induces phosphorylation and de-activation of the repressor 4E-BP1, resulting in its dissociation from the eukaryotic initiation factor-4E to initiate protein translation. I provide evidence that CCL5 initiates rapid translation of cyclin D1 and MMP-9, known mediators of cell migration. The data demonstrated that up-regulation of chemotaxis-related proteins may “prime” T cells for efficient migration. During an immune response, recently recruited T cells are exposed to high CCL5 concentrations. The propensity of CCL5 to form higher-order aggregates at high, µM concentrations, prompted studies to investigate their effects on T cell function. I show that at these high doses, CCL5 induces apoptosis in PM1.CCR5 and MOLT4.CCR5 T cell lines. CCL5-induced cell death involves the cytosolic release of cytochrome c and caspase-9/-3 activation. Furthermore, I identified Tyrosine-339 as a critical residue within CCR5, suggesting that tyrosine phosphorylation signalling events are important in CCL5-mediated apoptosis. Our data suggest that CCL5-induced cell death, in addition to Fas/FasL mediated events, may contribute to clonal deletion of T cells during an immunological response. I subsequently examined the possible pathological consequence of aberrant CCL5/CCR5 signalling in breast cancer. Exogenous CCL5 enhances MCF-7.CCR5 proliferation, which is abolished by anti-CCR5 antibody and rapamycin. CCL5 induces the formation of the eIF4F translation initiation complex, and mediates a rapid up-regulation of cyclin D1, c-Myc and Dad-1 protein expression. Thus, our data demonstrate the potential for breast cancer cells to exploit downstream CCL5/CCR5 signalling pathways for their proliferative and survival advantage. Taken altogether, each of these studies reinforces the notion that chemokines are not only potent chemotactic mediators, but are key effectors in diverse developmental, immunological and pathological processes.

Keywords: Chemokines
T cells
Signal Transduction
Apoptosis
Advisor: Fish, Eleanor N.