2013/2014 collection

Permanent URI for this collection

https://hdl.handle.net/10315/31601

ETDs in this collection are being checked for completeness and are in the process of being transferred to their respective collections under the FGS ETD collection umbrella.

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Open Access
Young, well-educated and adaptable people: Chilean exiles, identity and daily life in Canada, 1973 to the present day
Peddie, Francis David; Rubenstein, Anne; Perin, Roberto
"This dissertation describes the challenges and changes to lifestyle and identity experienced by twenty-one Chileans who came to Canada as exiles between 1973 and 1978. It is based largely on the testimony of the exiles themselves, augmented by research conducted at archives in Canada, Chile and the 'united States as well as primary and secondary sources that focus on modem Chilean history, Canadian immigration history, and the subject of exile. The experiences of the people I interviewed are contextualized by relating them to the events that pushed them out of Chile following the coup d'état of 11 September 1973, and the process by which they gained entry into Canada despite being from the wrong side of the Cold War ideological divide. Once resettled in Canada, the interviewees became part of a community whose primary raison d'être was to denounce the military government that ruled their homeland and denied them their place in the Chilean nation. The development of a culture of exile gave Chileans in Canada both a sense of continued belonging to their vision of the national community and also an outlet to express their condemnation of the regime that had made them outcasts. At the same time, I argue that the Chilean exiles of the 1970s eventually experienced transformations in their sense of personal and collective identity as the years passed and they became connected to their Canadian surroundings through work, family life and a new sense of belonging. The integration of many Chilean exiles into Canadian society, in turn, illustrates how immigration and refugee policy at the time favored the admission of ""young, well-educated and adaptable people"" who could become successful immigrants and bring benefits to the country, regardless of their ideological beliefs."
Open Access
The impact of topography and albedo on weather patterns and the location of the Martian South polar CO2 ice cap
Fazel Rastgar, Farahnaz; McConnell, Jack; Taylor, Peter; Whiteway, Jim
Meteorological and physical results from the second version of Global Mars Multiscale Model (GM3-v2) were used to investigate the impact of topography and albedo on the Martian southern polar CO2 ice cap. Analysis of the numerical simulations revealed significant differences in the horizontal and vertical cross sections of temperature when model was run for plain topography. Wind streamlines from Ls= 20° (early southern fall) to Ls = 200° (early southern spring) for every one Ls have been analysed. Wind streamline pattern analysis shows there are two cyclonic circulations during southern winter; one around the Hellas basin (in the eastern hemisphere) and the second one around the Argyre basin (in the western hemisphere). However, between these two cyclonic cells, the pattern is anti-cyclonic. Since the albedo map which is used in the model represents a mean state of albedo for all seasons of the planet, the albedo values have been modified in the polar regions to allow for the formation of the surface ice in the model. Also this modification will be very important in the water cycle simulation. As a second step in this work, the albedo values at the poles (mostly focusing on south polar regions) were modified for a better representation of the physical situation. However, the seasonal carbon dioxide ice in the polar regions is presented in the surface ice simulation by the second version of Global Mars Multiscale Model, but it does not produce a permanent south CO2 ice cap, and so it must be modified in the physics code in order to capture the real physical and meteorological processes. The permanent south CO2 ice cap in the model can significantly improve the representation of south polar meteorology for example in predicted surface temperatures, surface pressures, horizontal and zonal winds over the south cap and also possible initiation of dust storms at south polar region during the southern summer period. In the final part to this thesis, the residual CO2 ice cap is simulated in the physics code.
Open Access
Reduction of initial convergence period in GPS PPP data processing
Seepersad, Garrett Goberdhan; Bisnath, Sunil
Precise Point Positioning (PPP) has become a popular technique to process data from GPS receivers by applying precise satellite orbit and clock information, along with other minor corrections to produce cm to dm-level positioning. Although PPP presents definite advantages such as operational flexibility and cost effectiveness for users, it requires 15-25 minutes initialization period as carrier-phase ambiguities converge to constant values and the solution reaches its optimal precision. Pseudorange multipath and noise are the largest remaining unmanaged errors source in PPP. It is proposed that by reducing these effects carrier-phase ambiguities will reach the correct steady state at an earlier time, thus reducing the convergence period of PPP. Given this problem, this study seeks to improve management of these pseudorange errors. The well-known multipath linear combination was used in two distinct ways: 1) to directly correct the raw pseudorange observables, and 2) to stochastically de-weight the pseudorange observables. Corrections to the observables were made in real-time using data from the day before, and post-processed using data from the same day. Post-processing has shown 4 7% improvement in the rate of convergence, as the pseudorange multipath and noise were effectively mitigated. A 36% improvement in the rate of convergence was noted when the pseudorange measurements were stochastically de-weighting using the multipath observable. The strength of this model is that it allows for real-time compensation of the effects of the pseudorange multipath and noise in the stochastic model.
Open Access
Disrupting the discourse: Canadian Black women teachers in the lives of marginalized students
Tavares, Kimberley Ann; James, Carl; Crichlow, Warren; Tarc, Aparna Mishra
"This dissertation begins with a specific question: What can education learn from experiences of Black women teachers about meeting the educational needs of marginalized learners? It explores this question by focusing on the pedagogical practices five Canadian Black women teachers employ to meet the learning needs of their students, particularly those most marginalized and underserviced. While their voices are generally missing in Canadian educational research literature, the present inquiry is guided by an understanding that the teaching practices of Black women teachers are individualized and contextual; they encounter and develop professional expertise from many different subjective and educational trajectories, and they learn to teach students, on multiple terms and at varied levels of success. The research pursues three lines of investigation organized by the diverse experiences of Black women teacher respondents: (1) biographical and identity formation as teachers who are Black women; (2) attitudes, strategies and negotiations as ""minority"" teachers in a white majority profession; (3) and what matters most to these Black women about the academic success of marginalized students while teaching and interacting with them in the classroom. Drawing upon observations and interviews, insights from the teachers highlight the educational problematic as more about the long-standing ""teaching-gap"" than about challenges students present. The study yields recommendations toward closing this ""teaching gap"" to more generally improve educational provision to all students, and more specifically to marginalized students in Canadian schools."
Open Access
The feasibility of using feature-flow and label transfer system to segment medical images with deformed anatomy in orthopedic surgery
Zhao, Yao Jun; Ma, Burton; Elder, James; Godfrey, Parke; Schneider, Keith A.
In computer-aided surgical systems, to obtain high fidelity three-dimensional models, we require accurate segmentation of medical images. State-of-art medical image segmentation methods have been used successfully in particular applications, but they have not been demonstrated to work well over a wide range of deformities. For this purpose, I studied and evaluated medical image segmentation using the feature-flow based Label Transfer System described by Liu and colleagues. This system has produced promising results in parsing images of natural scenes. Its ability to deal with variations in shapes of objects is desirable. In this paper, we altered this system and assessed its feasibility of automatic segmentation. Experiments showed that this system achieved better recognition rates than those in natural-scene parsing applications, but the high recognition rates were not consistent across different images. Although this system is not considered clinically practical, we may improve it and incorporate it with other medical segmentation tools.
Open Access
Seasonal and long-term trends in the diatom and phytoplankton community composition of Lake Simcoe, Ontario
Tennant, Tara-Lynn Amy; Molot, Lewis; Quinlan, Roberto; Yan, Norman D.
Lake Simcoe and the Laurentian Great Lakes are among the freshwaters of the world that have collectively experienced accelerated rates of qualitative and quantitative degradation from multiple anthropogenic influences. Recent stressors include the introduction of invasive species, eutrophication and climate change. This study is twofold: 1) a short-term study (2009-2011) monitoring the diatom relative abundance during the ice-free and ice-covered periods using sediment traps and pelagic sampling methods and 2) a long-term study (1980-2011) monitoring trends in the total phytoplankton and diatom spring blooms. Seasonal phytoplankton relative abundances were analyzed for changes in dominant species and correlated to environmental variables. In the short term study diatom community structures of the ice-free and ice-covered sediment traps were statistically different (p = 0.0003) as were the ice-free pelagic and adjacent sediment traps (p = 0.0001): the diatom assemblages of the four sites, however, were not statistically different. Overall, the pelagic samples were dominated by Stephanodiscus minutulus/parvus and Fragilaria crotonensis. The ice-free sediment traps were dominated by Stephanodiscus binderanus and Fragilaria crotonensis and the ice-covered sediment traps were dominated by Stephanodiscus minutulus/parvus. Although total phosphorus (TP) was significantly related to the ice-free pelagic diatom community, this was not the case in the sediment traps. Silica (Si) concentrations were significantly 'drivers' in all sampling methodologies and chloride concentrations were also important in shaping the ice-free pelagic and ice-covered sediment communities. In the long-term study, there were no significant changes in the total phytoplankton or diatom biovolumes in the spring between the 1980s and the 2000s. There was however, evidence of a shift from larger Stephanodiscus species to Cyclotella, and smaller Stephanodiscus species. There is also evidence that the spring bloom may begin under the ice. A shorter ice-covered period lengthens the ice-free season which could cause earlier spring blooms.
Open Access
Place, meaning and sociality: exploring fullness in the themed retail environment
Darmody, Aron Thomas; Fischer, Eileen
"This paper describes an investigation of themed retail environments that provides a more complete understanding of how of retail environments or servicescapes ""build relationships with customers"" (Hollenbeck, Peters and Zinkhan 2008, p. 334). The research is the result of a three-year ethnographic study of five small Irish pubs. In my analysis I adapt Daniel Miller's (2008) concept of ""Fullness,"" which refers to an experience of place as meaningful and social. In more Full places we see how interpersonal relationships can abound and I show how different retailers are more and less successful at facilitating this sociality and at building relationships. For this I draw on Manuel DeLanda's (2006) notion of the assemblage to show that the Fullness we see in retail settings can be conceptualized and understood as emerging from an assemblage of material and nonmaterial components, each unique and dynamic over time, and all not necessarily present in one setting at the same time. Among the contributing components to Fullness, I identify three particularly potent mutually reinforcing ones: 1) material elements of the space, channelling and shaping interactions to provide elements of a mise-en-scene that facilitate sociality, 2) an assemblage of a core group of consumers in a retail space who themselves construct a narrative that holds that their ties to one another are forged and re-affirmed by the retail space in which they interact, 3) lead marketers who draw on personal resources and invoke marketplace myths. I also show how a variability of components can lead to variability in the forms of emergent Fullness. Finally, in detailing ways in which retail environments can be understood as assemblages of material and nonmaterial elements - dynamic entities that can be stabilized by some elements, destabilized by others - I identify implications for areas of retail and marketing management."
Open Access
Dharma noise: parergonality in Zen Buddhism and non-idiomatic improvisation
Schnee, Daniel Paul; Sokol, Keith
The objective of this dissertation is to explore philosophical and practical approaches to the study of improvisation in relation to Japanese Zen Buddhist doctrine and aesthetics. It specifically asks whether free form (non-idiomatic) improvisation can be practiced, and Zen Buddhism's efficacy in establishing a structured regimen for technical study on a musical instrument. In order to complete this research objective, the historical development of Zen Buddhist doctrine and aesthetics is investigated and shown to be a non-unified rubric. Using the concept of the parergon, it is then demonstrated that practicing is an appropriate activity for improvisation when supplemented by the kata forms of Zen-influenced Japanese arts. The result of such supplementation in .this case takes the form of a series of original chromatic exercises developed as a paradigm that itself acts as a supplement to improvisation. The establishment of such a regimen also suggests further research into the topic of pedagogy and Shintoism as an aesthetic or theological supplement, as well as gender issues in creative performance.
Open Access
"Beyond the ""usual suspects"": Black youth perspectives on africentric schooling"
George, Rhonda; Norquay, Naomi; Crichlow, Warren; James, Carl
Much has been said about the establishment and ongoing development of the Toronto District School Board's Africentric Alternative (Elementary) School in Toronto, which was intended to address the achievement gap for Black students and provide an alternative pedagogical approach. Currently on the horizon is the expansion of this initiative by the TDSB, through the implementation of a secondary school program tentatively called the Leonard Braithwaite Program, which will not operate as a stand alone school, but as an academic stream within an existing school on the East end of Toronto. Given, the heavy criticism from media, academics, parents and policy makers, it appears that adults are dominating the discourse about Africentric Schooling. Therefore, my masters' thesis aims to give voice to the very students that the Leonard Braithwaite Program aims to reach. Using a phenomenological qualitative approach and Critical Race Theory as a conceptual frame, my study queries how Black students between the ages of 16-20 from the Greater Toronto Area, come to understand Africentric Schooling as an academic option. The participants in this study divulge how their current and past racial, cultural and social climates coupled with their previous schooling experiences shape their thinking about Africentric Schooling. The participants also incite new ways of understanding how youth in the GT A are taking up this issue and what they feel is missing from the current discourse.
Open Access
A topological theory of (T,V)-categories
Sozubek, Serdar; Tholen, Walter
Lawvere's notion of completeness for quantale-enriched categories has been extended to the theory of lax algebras under the name of L-completeness. In this work we introduce the corresponding morphism concept and examine its properties. We explore some important relativized topological concepts like separation, density, compactness and compactification with respect to L-complete morphisms. We show that separated L-complete morphisms belong to a factorization system. Moreover, we investigate relativized topological concepts with respect to maps that preserve L-closure which is the natural symmetrized closure for lax algebras. We provide concrete characterizations of Zariski closure and Zariski compactness for approach spaces.
Open Access
Top girls: conventional costumes and a digitized stage design
Spidell, Scott George; Kerwin, Shawn
Top Girls: Conventional Costumes and a Digitized Stage Design describes the process of designing the projected sets and traditional costumes for an intermedial production of Caryl Churchill's Top Girls. Intermediality in performance refers to a blending or fusion of differing media in a production. What this practical thesis intends to do is explore the possibility of marrying some of the new techniques of video projection mapping with the requirements of theatrical scenic and prop design, using a limited budget. The intent of this thesis is to demonstrate that a basic mapping overlay of set and props images over simple surfaces is easily attainable.
Open Access
Development of a tandem microfluidic two-phase extraction device for continuous arylboronic acid phase-switching purification
O'Brien, Paul J.; Organ, Michael G.; Wilson, Derek; Orellana, Arturo
The last 20 years has witnessed a surge in the development of fluidic devices and techniques aimed at the generation of novel tools for chemical transformations, chemical analysis, bioassays, therapeutics, medical diagnostics, and in vivo tissue research. A growing area of research involves the use of microfluidics to facilitate reaction optimization and chemical synthesis on a large scale. Although there have been significant gains such as the incorporation of microwave heating, better mass-heat transport, and reduction of impurities through accurate control of reagent addition and reaction parameters, there is a lack of continuous purification techniques to accompany these processes. The development of continuous in-line purification processes is required for the wide scale adoption of continuous flow synthesis. It is necessary since multistep syntheses generally require changing solvents and removal of spent reagents and salts for downstream unit operations or analysis. Developing homogeneous in-line purification processes for flow synthesis would be a boon for industry by enhancing multistep fluidic processes by streamlining unit operations, enabling on demand synthesis of pharmaceuticals for market, resulting in lower costs from storage, spoilage and consignment returns. To achieve this, a method must continuously purify reaction mixtures of salts and by-products for mass spectrometric analysis to produce real-time second by second analysis of flow reactions. We have developed a microfluidic device to perform a tandem extraction process utilizing reversible acid/base phase switching properties of stable arylboronic acids. Using the complexation of boronic acids to 1,3 diol containing sugars, such as glucitol to produce boronic esters with strong hydrogen bonding ability, an aliphatic boronic acid functionalized molecule can be phase transferred from organic to aqueous media and vice versa, to facilitate the removal of impurities under continuous flow conditions. The current project involved the design and optimization of a simple hybrid device composed of perfluoropolymer film and stainless steel to construct a cheap, easily fabricated and configurable for rapid phase partitioning of boronic acids as a proof of concept methodology for continuous flow purification. Although continuous flow synthesis using fluidic systems has shown promise for single step synthesis, there is considerable difficulty in performing sequential steps to build complex small molecules. However, with the development of a continuous flow purification method this may be ameliorated so that a general method of multistep synthesis can be developed. The use of extraction techniques to facilitate purifications in continuous flow systems may prove to be a reliable and sustainable method for small scale as well as industrial scale synthesis as opposed to the use of liquid chromatography of intermediates, which introduces greater unit operations, steps and exponentially increases costs of APIs. Although the current project was not successful in generating a fully optimized device with a total arylboronic acid recovery of ~95%, we did achieve a high recovery of 75%. The proof of concept device demonstrated the utility and promise this system holds for developing multistep inline synthesis and analysis in-flow but requires further work to fabricate a more suitable microfluidic device to conduct arylboronic acid phase-switching purifications.
Open Access
The struggle for liberation from caste and gender: representations of Dalit women in the neo-Buddhist movement
Hibbs, Carolyn Annette; Scott, Jamie; Lee, Becky; Persram, Nalini T
This dissertation analyzes the representations of Dalit neo-Buddhist women in literature, iconography, and media, and situates these representations in a religious context. It fills a gap in the existing research by bringing together three areas of study, all of which are interdisciplinary in themselves and all of which intersect: religious studies, women's studies, and postcolonial studies. A central feature of the contemporary Dalit movement is its response to B. R. Ambedkar's founding of a new sect of Buddhism in 1956; this sect is popularly known as neo-Buddhism. Ambedkar founded this sect as a means to counter casteism and sexism in India. This dissertation proposes that religious experience is central to the neo-Buddhist movement, to the experiences of women within that movement, and to the production of representations of Dalit women. This dissertation situates neo-Buddhism as a religion which engages with the intersection of gender and caste, and considers the impact of the text The Buddha and His Dhamma as scripture. It also situates neo-Buddhism in the context of historical responses to the caste system in non-Hindu traditions, and the contemporary practice of casteism and sexism in those traditions. It argues that in his founding of neo-Buddhism, Ambedkar drew on both indigenous and foreign models in order to challenge both Hindu and colonial oppression. Non-Dalits, Dalit men, and Dalit women all respond to Ambedkar and neo-Buddhism. This dissertation argues that Dalit men's representations of Dalit women tend to reinforce upper caste Hindu concepts of womanhood through the idealization of self-sacrificing devotion, domesticity, and purity. In contrast, in their self-representations, Dalit women participate in Buddhist feminist theology through engaging with concepts of religion, rationality, and the polluted body. The dissertation concludes that Dalit women's engagement with casteism and sexism both follows Ambedkar's example and provides a stronger means of countering casteism and sexism in their Dalit communities, and in Indian culture more broadly.
Open Access
Safe schools for (almost) everyone: the Christian Right's resistance to Ontario's LGBT inclusive 'Accepting Schools Act'
Meraglia, Frank Augustus; Anderson, Karen; Murdocca, Carmela
The Christian Right is an important and influential voice in contemporary political discourses and popular culture within Canadian society. This research seeks to analyze the discourses and framing strategies utilized in arguments by the following Christian Right organizations in Ontario: The Institute for Canadian Values, Evangelical Fellowship of Canada, and the Family Coalition Party. Each of these groups opposes the passage of Bill 13: Accepting Schools Act. The aim of the Bill was to introduce LGBT inclusive anti-bullying policies into all Ontario classrooms. A comprehensive content analysis of standing committee transcripts, official documents, multimedia records of interviews, transcripts or public speaking events, and websites/articles produced by these Christian Right organizations in Ontario are analyzed to uncover recurring themes, patterns and objectives of current discourses surrounding this issue. This research provides insights into the rhetorical strategies being utilized by these Christian Right organizations in Ontario as they fight the Accepting Schools Act.
Open Access
DragonflEYE: a passive approach to aerial collision sensing
Minwalla, Cyrus; Hornsey, Richard; Thomas, Paul
"This dissertation describes the design, development and test of a passive wide-field optical aircraft collision sensing instrument titled 'DragonflEYE'. Such a ""sense-and-avoid"" instrument is desired for autonomous unmanned aerial systems operating in civilian airspace. The instrument was configured as a network of smart camera nodes and implemented using commercial, off-the-shelf components. An end-to-end imaging train model was developed and important figures of merit were derived. Transfer functions arising from intermediate mediums were discussed and their impact assessed. Multiple prototypes were developed. The expected performance of the instrument was iteratively evaluated on the prototypes, beginning with modeling activities followed by laboratory tests, ground tests and flight tests. A prototype was mounted on a Bell 205 helicopter for flight tests, with a Bell 206 helicopter acting as the target. Raw imagery was recorded alongside ancillary aircraft data, and stored for the offline assessment of performance. The ""range at first detection"" (R0), is presented as a robust measure of sensor performance, based on a suitably defined signal-to-noise ratio. The analysis treats target radiance fluctuations, ground clutter, atmospheric effects, platform motion and random noise elements. Under the measurement conditions, R0 exceeded flight crew acquisition ranges. Secondary figures of merit are also discussed, including time to impact, target size and growth, and the impact of resolution on detection range. The hardware was structured to facilitate a real-time hierarchical image-processing pipeline, with selected image processing techniques introduced. In particular, the height of an observed event above the horizon compensates for angular motion of the helicopter platform."
Open Access
Tyrosine phosphorylation in Tetrahymena thermophila during intercellular communication
Kume, Albana; Pearlman, Ronald; Scheid, Michael P.
Emerging evidence suggests that tyrosine phosphorylation signaling is present in unicellular organisms. There is also emerging evidence suggesting the presence of tyrosine phosphorylation in the unicellular ciliate protozoan, Tetrahymena thermophila. T. thermophila shares a high number of orthologs with humans. Understanding tyrosine phosphorylation in unicells could help us understand how this pathway works in multicells. In this investigation, tyrosine phosphorylation signaling is investigated in T thermophila during starvation and conjugation as it could play a role in mating in this organism. This was done by applying Western blot, indirect immunofluorescence microscopy, bioinformatics, and gene knockout. The immunodetection methods combined with anti-phosphotyrosine antibody suggest the presence of tyrosine phosphorylation in starved and conjugating cells. The bioinformatic data also show proteins that could be tyrosine phosphorylated during starvation and conjugation. In addition, for one of these proteins, its gene was prepared for investigation by knocking out its coding region and replacing it with a neo4 cassette to investigate its role and possible relevance to tyrosine phosphorylation signaling. These data combined with previous work suggest that there is tyrosine phosphorylation signaling in T. thermophila that occurs during mating and preparation for mating.
Open Access
Regional climate modeling over Ontario using the WRF model
Yu, Zhongqi; Chen, Yongsheng; Huang, Gordon; Liu, John
Global climate models (GCMs) are widely used to study climate change. Due to their coarse resolutions, GCMs cannot resolve some microscale and mesoscale processes such as topographical effects. Dynamic downscaling simulations using Regional Climate Models (RCMs) are often required to provide higher spatial- and temporal-resolution climate variabilities in specific regions. Uncertainties in dynamic downscaling simulations due to errors in the atmospheric state and models need to be understood first in the present climate simulations. Then the reliability for future projections can be inferred. This research contains three parts. The first part gives an assessment of temperature and precipitation over Ontario based on the North American Regional Climate Change Assessment Program (NARCCAP) RCM simulation data. In part two, five 8-year downscaling simulations using the Weather Research and Forecasting (WRF) model driven by five NARCCAP model data over Ontario are studied. Each of these simulation results and their mean are analyzed to address the dynamic downscaling effect on temperature and precipitation and their variabilities. Lastly in the third part, a 14-member perturbed ensemble simulation using the WRF model was conducted. The ensemble means of temperature and precipitation are evaluated and the uncertainties in regional climate modeling are discussed. The temperature and precipitation in seven NARCCAP RCM simulations from 1979 to 2004 are compared to the observations over Ontario. The observed annual area mean temperature has a remarkable rising trend in the late 1990s after decades of fluctuation. It is mainly due to a significant rise of winter area mean temperature during that period. This rising trend has been revealed in all seven models. For the annual area mean precipitation, the observed values fluctuate during this period, and the NARCCAP RCM model simulations show larger discrepancies. One focus of this thesis is to assess the impact of increased model resolution on regional climate simulations. Five NARCCAP RCM (MM5I, RCM3, HRM3, CRCM and WRFG) simulation data with 50-km horizontal resolution are downscaled to 10-km horizontal grid over Ontario to provide initial and boundary conditions for the WRF downscaling simulations in the period from 1991 to 1998. The model results show that the high resolution has great impact on regional climate simulations. Three sets of ensembles, the seven-member NARCCAP RCM simulations, the five-member WRF downscaling simulations, and a 14-member perturbed ensemble simulations using WRF model with the stochastic kinetic energy backscatter scheme are analyzed to assess the performance of the ensemble approach in regional climate simulations. The ensemble mean temperature and precipitation are compared to reanalysis data and the observations. The root mean square errors (RMSE) and the correlations are calculated. The results show that the ensemble method improves the accuracy of simulations, for both temperature and precipitation.
Open Access
Age differences in the experience of cancer pain
Gauthier, Lynn Rollande; Gagliese, Lucia; Macpherson, Alison; Pillai Riddell, Rebecca
The aim of this dissertation is to elucidate age-related patterns in the multidimensional experience of cancer pain. Chapter 1 presents a literature review of age-related patterns in cancer pain, outlines the methodological limitations of existing literature and highlights gaps in our knowledge. Chapter 2 presents the first psychometric analysis of the Short-Form McGill Pain Questionnaire-2 in older and younger people with cancer pain. The weight of the evidence suggests that this tool is valid for use in older and younger people with cancer pain. Chapter 3 presents an analysis of age-related patterns in the experience of cancer pain across the biopsychosocial spectrum. Pain intensity, qualities, and interference did not differ across age groups but older patients were somewhat less likely to be prescribed an opioid. Comorbidity was associated with greater pain for younger, but not older people, and chronic nonmalignant pain was associated with greater pain for older, but not younger people. An age-related pattern in the supportive context of cancer pain based on health status factors may also be present. There were no age differences in depressive symptoms, but intrusive thoughts were associated with greater pain for younger but not older patients, suggesting a unique adaptive advantage of prior experience with health limitations among older, but not younger patients. Chapter 4 presents a preliminary investigation of the role of pain three months after breast cancer surgery in the relationship between age and depressive symptoms. In women with moderate-to-severe pain, age was not associated with depressive symptoms but in women with mild or no pain, younger age was associated with greater depressive symptoms. However, in women with neuropathic pain, younger age was associated with greater depressive symptoms, but not in women without neuropathic pain. The impact of pain was not age-related. High preoperative pain expectations may be a risk factor for pain three months after breast cancer surgery, regardless of age. In Chapter 5, results are integrated and discussed along with implications for future research and treatment.
Open Access
The application of MAX-DOAS to the measurement of tropospheric gases and aerosols in marine and continental environments
Halla, Jamie Dustin; McLaren, Robert; Bottenheim, Jan W; Harris, Geoffrey W.
Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) is a passive DOAS technique that uses scattered sunlight to determine differential slant column densities (DSCDs) of trace gas absorbers along multiple axes. MAX-DOAS measurements probe long path lengths, and when coupled with a radiative transfer model (RTM) to determine the average light path travelled, MAX-DOAS has the potential to yield trace gas vertical column densities (VCDs), aerosol optical depths, and trace gas and aerosol layer heights. Determination of DSCDs and VCDs have advantages over point-source measurements in that they are more sensitive to the total atmospheric load of a pollutant, and are relatively insensitive to variations in the boundary layer height. Two Canadian field campaigns: one from Saturna Island, BC, located in the Strait of Georgia; the other from Ridgetown, ON, in southwestern Ontario; employed a MAX-DOAS instrument to obtain spectra that were analyzed to yield DSCDs of NO2, O4 and HCHO. The measured spectra from Ridgetown were also compared to RTM calculations to yield NO2 VCDs, aerosol optical depths, and gas and aerosol layer heights. The method of determining NO2 VCDs in this way was validated for the first time by comparison to composite VCDs derived from aircraft and ground-based measurements of NO2, satellites, and a chemical model. The usefulness of the MAX-DOAS technique was extended further, using both DSCDs and VCDs, to include the interpretation of pollutant transport at Saturna and Ridgetown, and to provide an example of fumigation of elevated industrial pollutants brought to the surface at a lake breeze front at Ridgetown.
Open Access
Search beyond traditional probabilistic information retrieval
Hu, Qinmin; Huang, Jimmy
"This thesis focuses on search beyond probabilistic information retrieval. Three ap- proached are proposed beyond the traditional probabilistic modelling. First, term associ- ation is deeply examined. Term association considers the term dependency using a factor analysis based model, instead of treating each term independently. Latent factors, con- sidered the same as the hidden variables of ""eliteness"" introduced by Robertson et al. to gain understanding of the relation among term occurrences and relevance, are measured by the dependencies and occurrences of term sequences and subsequences. Second, an entity-based ranking approach is proposed in an entity system named ""EntityCube"" which has been released by Microsoft for public use. A summarization page is given to summarize the entity information over multiple documents such that the truly relevant entities can be highly possibly searched from multiple documents through integrating the local relevance contributed by proximity and the global enhancer by topic model. Third, multi-source fusion sets up a meta-search engine to combine the ""knowledge"" from different sources. Meta-features, distilled as high-level categories, are deployed to diversify the baselines. Three modified fusion methods are employed, which are re- ciprocal, CombMNZ and CombSUM with three expanded versions. Through extensive experiments on the standard large-scale TREC Genomics data sets, the TREC HARD data sets and the Microsoft EntityCube Web collections, the proposed extended models beyond probabilistic information retrieval show their effectiveness and superiority."