title: A Computational and Experimental Study of Surface Acoustic Waves in Phononic Crystals

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subject:
surface acoustic waves
phononic crystals
finite-difference time-domain
microfabrication

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-12-23 16:24:33.164

abstract:
The unique frequency range and robustness of surface acoustic wave (SAW) devices has been a catalyst for their adoption as integral components in a range of consumer and military electronics. Furthermore, the strain and piezoelectric ﬁelds associated with SAWs are ﬁnding novel applications in nanostructured devices. In this thesis, the interaction of SAWs with periodic elastic structures, such as photonic or phononic crystals (PnCs), is studied both computationally and experimentally.

To predict the behaviour of elastic waves in PnCs, a ﬁnite-difference time-domain simulator (PnCSim) was developed using C++. PnCSim was designed to calculate band structures and transmission spectra of elastic waves through two-dimensional PnCs. By developing appropriate boundary conditions, bulk waves, surface acoustic waves, and plate waves can be simulated. Results obtained using PnCSim demonstrate good agreement with theoretical data reported in the literature.

To experimentally investigate the behaviour of SAWs in PnCs, fabrication procedures were developed to create interdigitated transducers (IDTs) and PnCs. Using lift-off photolithography, IDTs with ﬁnger widths as low as 1.8 um were fabricated on gallium arsenide (GaAs), corresponding to a SAW frequency of 397 MHz. A citric acid and hydrogen peroxide wet-etching solution was used to create shallow air hole PnCs in square and triangular lattice conﬁgurations, with lattice constants of 8 um and 12 um, respectively. The relative transmission of SAWs through these PnCs as a function of frequency was determined by comparing the insertion losses before and after etching the PnCs. In addition, using a scanning Sagnac interferometer, displacement maps were measured for SAWs incident on square lattice PnCs by Mathew (Creating and Imaging Surface Acoustic Waves on GaAs, Master’s Thesis). Reasonable agreement was found between simulations and measurements. Additional simulations indicate that SAW waveguiding should be possible with a PnC consiting of air holes in GaAs.

The phononic properties of a commonly used photonic plate were also determined. Band structure simulations of the plate displayed no complete elastic band gaps. However, transmission simulations indicated that a pseudo-gap may form for elastic waves polarized in the sagittal plane.

abstract: M.Sc.


title: Investigating the role of reactive oxygen species in transplacental benzene carcinogenesis

contributor:
Winn, Louise M.
Pharmacology and Toxicology

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rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject:
Benzene
Childhood leukemia

abstract: Thesis (Ph.D, Pharmacology & Toxicology) -- Queen's University, 2009-12-21 13:10:12.747

abstract: The incidence of childhood leukemia is increasing, especially in urbanized areas. It is hypothesised that transplacental exposure to environmental carcinogens, such as benzene, plays a role in the etiology of childhood cancers.  The studies in this thesis investigated mechanisms of transplacental benzene tumourigenesis focusing on the role of reactive oxygen species (ROS). Initially, we investigated the effect of maternal benzene exposure on fetal erythroid progenitor cell number and the role of ROS in benzene metabolite-induced dysregulation of erythropoiesis. In the CD-1 mouse, in utero benzene exposure caused significant alterations in female fetal liver erythroid progenitor cell numbers at gestational day 16 and postnatal day 2. Using an in vitro chicken erythroblast cell line capable of erythropoiesis, we found that hydroquinone significantly inhibited erythropoiesis and this effect was prevented by pretreatment with PEG-superoxide dismutase. The second objective investigated the role of ROS in dysregulated fetal hematopoietic progenitor cell growth after maternal benzene exposure in C57Bl/6N mice.  In utero exposure to benzene caused changes in fetal hematopoietic progenitor cell numbers, an increase in levels of fetal liver intracellular ROS, and a decrease in IκB-α protein levels, which were all prevented by pretreatment with PEG-catalase. The final objective determined the incidence of cancer in offspring transplacentally exposed to benzene.  This study compared two strains of mice (C57Bl/6N and CD-1), as well as male and female offspring.  This study also measured levels of benzene and benzene metabolites present in maternal blood and fetal liver tissue after maternal benzene exposure. Transplacental exposure to benzene induced hepatic and hematopoietic tumours in male and female CD-1 mice, respectively. Interestingly, there were no significant changes in tumour incidence in C57Bl/6N mice demonstrating a significant strain difference in susceptibility to transplacental benzene carcinogenesis. Levels of fetal liver benzene metabolites also differed between genders and strains of mice suggesting that the gender and strain differences in tumour formation may be dependent on fetal benzene metabolism capability. In conclusion, this thesis supports the hypothesis that benzene exposure to pregnant women contributes to the etiology of childhood cancers and highlights ROS and fetal benzene metabolism as potential mechanisms.

abstract: PhD


title: Adaptive Output Feedback Stabilization of Nonlinear Systems

contributor:
Guay, Martin
Chemical Engineering

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subject:
Adaptive
Non-minimum Phase

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-12-22 15:47:05.884

abstract:
Output feedback control design techniques are required in practice due to the limited
number of sensors/measurements available for feedback. This thesis focuses on output
feedback controller design techniques for nonlinear systems subject to different system
restrictions.
The problem of controlling the heart dynamics in a real time manner is formulated
as an adaptive learning output-tracking problem. For a class of nonlinear dynamic
systems with unknown nonlinearities and non-affine control input , a Lyapunov-based
technique is used to develop a control law. An adaptive learning algorithm is exploited
that guarantees the stability of the closed-loop system and convergence of the output tracking error to an adjustable neighborhood of the origin. In addition, good
approximation of the unknown nonlinearities is also achieved by incorporating a per-
sistent exciting signal in the parameter update law. The effectiveness of the proposed
method is demonstrated by an application to a cardiac conduction system modelled
by two coupled driven oscillators.
An output feedback design technique is developed to achieve semi-global practical
stabilization for a class of non-minimum phase nonlinear systems, subject to param-
eter uncertainties. This work provides a constructive controller design method for an
auxiliary system, whose existence is crucial, but is only assumed in (Isidori, 2000).
The control design technique is used to regulate the benchmark van de Vusse reactor.
Simulation results demonstrate satisfactory controller performance.
The output feedback control design for a class of non-minimum phase nonlinear
systems with unknown nonlinearities is studied. The proposed approach is able to
combine the two previous design methods and provide a stabilizing output feedback
control law. The performance of the proposed method is demonstrated by simulation results.

abstract: PhD


title: Timing is everything: Early identification and the Double Deficit Hypothesis

contributor:
Kirby, John R.
Education

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subject:
early identification
reading difficulties
phonological awareness
naming speed
Double Deficit Hypothesis
stability

abstract: Thesis (Master, Education) -- Queen's University, 2010-01-06 12:54:02.063

abstract: The Double Deficit Hypothesis of dyslexia posits that students can be grouped into four distinct groups: (a) average readers, (b) students with phonological deficits, (c) students with naming speed deficits, and (d) students with double deficits: those having both (b) and (c). The present study examines the stability of the Double Deficit groups from Kindergarten to Grade 2. 214 children were assessed in Kindergarten and subsequently tested in early Grade 1, late Grade 1, and Grade 2. Tests administered at each time included measures of naming speed, phonological awareness, and a variety of reading measures. Discriminant analyses indicated that approximately 70% of Grade 2 children were successfully classified by Kindergarten measures. Contingency analyses indicated moderate stability from Kindergarten to Grade 2 and more movement between groups between Kindergarten and Grade 1. The Double Deficit groups differed in reading achievement at each testing time, with the Double Deficit group obtaining the lowest scores. Implications for early assessment and intervention are discussed.

abstract: M.Ed.


title: The effect of copper on kairomone-mediated responses by wild Daphnia pulicaria clones from along a copper gradient

contributor:
Arnott, Shelley E.
Pyle, Greg
Biology

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subject:
Daphnia
metal-tolerance
kairomone
antipredator defenses
copper

abstract: Thesis (Master, Biology) -- Queen's University, 2009-12-23 09:50:46.152

abstract:
Kairomones are infochemicals that benefit a heterospecific receiver.  Chaoborus spp. release a kairomone from their gut when feeding on Daphnia spp.  Daphnia respond to kairomone by shifting life history parameters or producing neonates with induced morphological defenses, increasing their chance of survival.  When laboratory-cultured Daphnia are exposed to environmentally-relevant metal concentrations, a kairomone response is not induced, increasing predation vulnerability.
Currently Daphnia live in metal-contaminated lakes in Sudbury, ON.  It is possible the extant population is tolerant of relatively high copper (Cu) concentrations and can still induce a kairomone response.  In comparison, it is hypothesized clones found in lakes isolated from anthropogenic sources of metal-contamination would be less tolerant as they have not been exposed to high Cu concentrations.
The purpose of this study was to examine how multiple clones of D. pulicaria obtained from lakes along a Cu gradient respond to kairomone in the absence and presence of copper.  Several different clones from Ontario lakes located in the Canadian Shield were exposed to environmentally-relevant Cu concentrations and Chaoborus kairomone.  Neonates were collected and measured to assess predator-induced defenses.
Results indicate that kairomone-mediated responses and Cu-tolerance vary among D. pulicaria clones.  Clones from the Sudbury area were able to induce a response to kairomone when exposed to Cu, indicating a Cu-tolerance.  However, this was not true for all Sudbury clones.  In contrast, most clones from clean lakes did not respond to kairomone when exposed to Cu; while some clones exhibited a Cu-tolerance.  Clones that were not tolerant of Cu were affected at concentrations much lower than those predicted by the Biotic Ligand Model (BLM) that induce acute toxicity.  Predictions generated by the BLM can be conservative making them useful when creating water quality criteria; however, my results indicate these predictions can also be under-protective.  Chemosensory cues mediate vital life processes that are essential for survival.  Populations may be devastated if metals interfere with chemosensory cues.  Overall, the results of my study suggest that genetic variation is important for population establishment and maintenance, specifically when exposed to multiple stressors, and that directional selection may result in stress tolerance.

abstract: M.Sc.


title: Selection of Simplified Models and Parameter Estimation Using Limited Data

contributor:
McAuley, Kimberly B.
Harris, Thomas J.
Chemical Engineering

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subject:
Simplified Models
Limited Data
Chemical Engineering
Model Selection

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-12-23 09:48:45.423

abstract:
Due to difficulties associated with formulating complex models and obtaining reliable estimates of unknown model parameters, modellers often use simplified models (SMs) that are structurally imperfect and that contain a smaller number of parameters.  The objectives of this research are: 1) to develop practical and easy-to-use strategies to help modellers select the best SM from a set of candidate models, and 2) to assist modellers in deciding which parameters in complex models should be estimated, and which should be fixed at initial values.  The aim is to select models and parameters so that the best possible predictions can be obtained using the available data and the modeller’s engineering and scientific knowledge.

This research summarizes the extensive qualitative and quantitative results in the statistics literature regarding the use of SMs.  Mean-squared error (MSE) is used to judge the quality of model predictions obtained from different candidate models, and a confidence-interval approach is developed to assess the uncertainties associated with whether a SM or the corresponding extended model will give better predictions.  Nine commonly-applied model-selection criteria (MSC) are reviewed and analyzed for their propensities of preferring SMs.  It is shown that there exist preferential orderings for many MSC that are independent of model structure and the particular data set.  A new MSE-based MSC is developed using univariate linear statistical models.  The effectiveness of this criterion for selecting dynamic nonlinear multivariate models is demonstrated both theoretically and empirically.  The proposed criterion is then applied for determining the optimal number of parameters to estimate in complex models, based on ranked parameter lists obtained from estimability analysis.  This approach makes use of the modeller’s prior knowledge about precision of initial parameter values and is less computationally expensive than comparable methods in the literature.

abstract: PhD


title: Cognitive Responses to Stress, Depression, and Anxiety and Their Relationship to ADHD (Attention Deficit Hyperactivity Disorder) Symptoms

contributor:
Lindsay, Roderick C. L.
Psychology

subject: ADHD Stress

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-12-24 12:28:52.937

abstract:
Abstract
This research sought to answer the question “To what extent do symptoms related to depression, anxiety and stress interfere with the valid measurement of Attention Deficit Hyperactivity Disorder (ADHD)?”   More specifically, “To what extent do these factors affect the Conner’s Adult ADHD Rating Scale (CAARS; Conners, Erdhardt, & Sparrow, 1999) and the BADDS (Brown Attention Deficit Disorder Scale; T. E. Brown, 1996), popular measures of ADHD status?”   I examined the number of people in “higher stress situations” scoring above accepted critical values on the subscales of the CAARS and on the BADDS in comparison to the general population.  Multiple regression analyses were conducted to determine the relationship between the level of depression, anxiety, stress, and ADHD symptomatology and to determine the amount of variance of CAARS and BADDS scores accounted for by each of these other psychological variables.  Three separate groups of people participated in this study: students from a Psychology 100 subject pool; students going to health or counselling services; and a group of nurses employed in a local hospital.  Participants completed questionnaires regarding self-reported levels of depression, anxiety, stress, life experiences, role stress, coping skills, and ADHD symptoms.  Self-reported levels of depression, anxiety, stress, and other factors were positively correlated with scores on the measures of ADHD symptomatology.  People who reported more anxiety, more depression, and/or more stress were more likely to score above critical values on the ADHD measures.

abstract: PhD


title: Thinking and Doing: Attributions and Coping of Children and Their Friends That Are Associated With the Continuity of Victimization and Bullying

contributor:
Craig, Wendy M.
Psychology

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subject: Children Bullying Coping Cognitions Victimization Friendships

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-12-29 15:17:14.814

abstract: Over the past three decades, childhood bullying research has developed. Although bullying was first understood as an individual problem, researchers now understand that bullying is a relationship problem. Children come to a social exchange with their own cognitions and coping strategies, but are also impacted by their peers. Developmental contextualism forms the macro level framework of these studies and states that change occurs reciprocally and across many levels including the individual, interpersonal, community, and society. Social cognitive theory (and social information processing, in particular) helps at the individual and interpersonal levels in understanding the role cognitions play in affecting children’s responses in social exchanges. The series of papers in this dissertation focus on: (1) How attributions and coping styles interact within victimized children and how that affects victimization; (2) How attributions and coping styles are associated in children who bully others and how that interaction affects bullying behaviour; and (3) How children’s friendships protect or put them at risk for victimization. Overall, results suggest that children’s attributions and coping are directly associated with victimization and bullying, but do not work together in a mediational relationship. Rather specific types of attributions and coping strategies are related to involvement in bullying and victimization both within and across time and differences exist between boys and girls. With regards to friendships, the identity and communication skills of one’s friends appear to be important. Findings suggest the need for interventions that teach victimized children and their friends how to cope effectively with victimization and communicate with each other about their needs.

abstract: PhD


title: Chinese University Students’ Motivation, Anxiety, Global Awareness, Linguistic Confidence, and English Test Performance: a Correlational and Causal Investigation

contributor:
Cheng, Liying
Education

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subject:
Chinese Learners
English Test Performance
College English Test (CET)
Structural Equation Modelling
Mixed Methods
Socio-Educational Model of Motivation
Test Anxiety
Language Anxiety
Global Awareness
Linguistic Confidence

abstract: Thesis (Ph.D, Education) -- Queen's University, 2009-12-30 22:08:41.138

abstract:
This study examined motivation, anxiety, global awareness, and linguistic confidence, and their relation to language test performance within the context of Chinese university students taking the College English Test Band 4(CET-4) in China. Using a mixed methods approach, through survey and interview inquiries, this study explored whether and how the selected psychological factors contributed to students’ CET performance. Results from exploratory factor analysis revealed that Chinese university students displayed three types of instrumental motivation (i.e., mark orientation, further-education orientation, and job orientation), two types of anxiety (i.e., language anxiety and test anxiety), and two types of confidence (i.e., linguistic confidence and test confidence). The results of confirmatory factor analysis led to a modified socio-educational model of motivation with some context-specific concepts (i.e., new instrumental orientations, global awareness, and linguistic confidence) that more accurately represented the characteristics of the Chinese university students. The results of structural equation modelling confirmed that attitude toward the learning situation and integrative orientation were two strong indicators of motivation, which in turn influenced language achievement and confidence. The negative impact of anxiety on language achievement was confirmed. Certain group differences were found in comparing male students with female students, high achievers with low achievers, students from the Arts programs with those from the Science programs, and students who started to learn English before Grade 7 with those
iii
who did so after Grade 7. The interview findings indicated stronger instrumental orientations than integrative orientations. External influences, including influences from society, teachers, and peers, were also identified. Students expressed their mixed feelings toward the CET-4, indicating that this test had both positive and negative influences in promoting their English learning. Testing well-developed motivation and anxiety models in the Chinese context enriched and expanded our knowledge in theory development in English language education in China. The implications of this study point to the importance of understanding language test-takers’ characteristics in their macro and micro learning contexts, as well as the importance of establishing the relevance of English language learning to language teaching, and testing in English as Foreign Language contexts.

abstract: PhD


title: An Experimental and Modelling Study of Oxygen Reduction in Porous LSM/YSZ Solid Oxide Fuel Cell Cathodes

contributor:
Karan, Kunal
Chemical Engineering

subject:
energy
solid oxide fuel cells
ceramics
oxygen reduction
cathode
LSM

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-12-31 11:53:23.535

abstract:
Solid oxide fuel cells (SOFCs) are electrochemical devices that can convert a variety of fuels directly into electricity. Their commercialization requires efficient operation of its components. The sluggish kinetics for the oxygen reduction reaction (ORR) at the SOFC cathode contributes to the loss in the fuel cell efficiency. In this work, the ORR was investigated for the strontium-doped lanthanum manganite cathode (LSM) and yttria-stabilized zirconia electrolyte (YSZ) system. A combined mathematical modelling and experimental framework was developed to estimate, for the first time, the kinetics of the elementary processes of the ORR for porous LSM cathodes. The kinetics of each process was then analyzed to identify the contribution to the cathode resistance.

The steady state and impedance response for polarized and unpolarized LSM cathodes was collected over a temperature range between 750C and 850C and two different oxygen partial pressure (pO2) ranges: (i) between 0.0001atm and 0.001atm, where LSM is considered to be stoichiometric with respect to oxygen and (ii) between 0.01atm and 0.21atm, where LSM is considered to be superstoichiometric with respect to oxygen.

A mathematical model was developed to analyze both the steady state and impedance data. Two pathways for the ORR were considered: one where oxygen is transported in the gas phase and one where oxygen is transported along the surface of the LSM cathode. Rate constants, transport coefficients and their respective activation energies were obtained for the adsorption/desorption, surface diffusion and charge transfer processes.

The experimental results indicated different polarization behavior between low and high pO2. It is hypothesized that the concentration of cation vacancies on the LSM surface changes with both pO2 and extent of polarization and that cation vacancies on the LSM surface can promote the ORR. Modelling results at low pO2 suggested that the adsorption reaction was slow and that thermodynamic limitations resulting in low equilibrium oxygen surface coverage can play an important role at both low and high polarizations. Modelling in high pO2 was complicated by the nature of the LSM surface in these conditions and suggests an electrochemical reaction at the gas/LSM interface and the transport of charged adsorbed oxygen atoms.

abstract: We expect to publish some data within this thesis soon.

abstract: PhD


title: Neural correlates of focused attention in cognitively normal older adults, patients with mild cognitive impairment and patients with mild Alzheimer's disease

contributor:
Garcia, Angeles A.
Neuroscience Studies

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subject:
functional magnetic resonance imaging
focused attention
Alzheimer's disease
mild cognitive impairment

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2009-12-31 11:57:52.374

abstract:
Impaired attention can hinder information processing at multiple levels and may explain some aspects of the cognitive decline in aging.  An inefficient inhibitory system can lead to deficits in focused attention (FA).  FA deficits are observed in patients with mild cognitive impairment and Alzheimer’s disease (AD).  The Stroop task was applied to functional magnetic resonance imaging (fMRI) to investigate the neural correlates of FA in cognitively normal older adults (NC), patients with amnestic MCI (aMCI) and patients with mild AD.
Twenty-one NC, seven aMCI and fifteen mild AD patients performed a verbal Stroop- fMRI paradigm.  Both structural and T2*-weighted functional scans were acquired.  In Series 0, subjects were presented with colour words printed in black ink and were asked to read the word.  In Series 1 and 2, subjects were presented with colour words printed in an incongruent ink colour.  Series 1 had four blocks of the ‘Read the word’ condition followed by four blocks of the ‘Say the colour of the ink’ condition. Series 2 had eight blocks of alternating ‘Read the word’ and ‘Say the colour of the ink’ conditions.  SPM5 was used to detect anatomical areas with significant signal intensity differences between the two conditions.
The NC group performed significantly better in the Stroop-fMRI task than the aMCI and mild AD groups.  The percentage of errors on incongruent trials was significantly lower in the NC group (2%) than the aMCI (14%) and mild AD (13%) groups.  The ‘Say the colour of the ink’ minus ‘Read the word’ contrast for the NC and mild AD groups yielded common areas of activation in the supplementary motor area, precentral gyrus, and inferior frontal gyrus.  aMCI patients also showed activation in the precuneus, temporal and postcentral gyri.
 Worse performance on the Stroop-fMRI task by the aMCI and mild AD groups suggests deficits in FA.  This is the first study to investigate the neural correlates of FA using the Stroop task in aMCI and AD patients.  The verbal Stroop-fMRI paradigm employed in the current study provides a means to study the neural correlates of FA in older adult and patient populations.

abstract: M.Sc.


title: IMMIGRANT AND REFUGEE STUDENTS’ CHALLENGES AND TEACHERS’ PEDAGOGICAL STRATEGIES

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subject:
Immigrant students
Refugee students
Classroom challenges
Pedagogical strategies

abstract: As Canada’s newcomer student population continues to rise and 42% of total new immigrants settle in Ontario (Canwest News Service, 2009), it becomes increasingly important to ensure that these students are adapting well and to their full potential within their host schools. The purpose of this project was two-fold: first, to review the existing literature on immigrant and refugee students’ challenges in the classroom and school community and second, to develop a teacher`s manual based on the documented challenges specific to newcomer students in the classroom, so that these teachers can be aware of these possible challenges, as well as use suggested pedagogical strategies to address these challenges. For the purposes of my project, I first investigated the challenges specific to immigrant students, followed by the challenges experienced by refugee students in the classroom and community. I then surveyed the literature to identify what the research classifies as pedagogical strategies directed towards classroom teachers who are working with these students. Findings from my review of the literature indicated that trauma, grief, and loss; learning the English language; and the intercultural experience are the three main areas of challenge for both immigrant and refugee students. Overarching educational policies, school wide practices, classroom strategeis, school-community relations, and professional development among teachers are the main themes revealed in the development of strategies for helping immigrant and refugee students overcome their educational challenges.


title: Characterization of the Potential Use of Salix Nigra and Populus Balsamifera for the Phytoremediation of 1,4-Dioxane

contributor:
Lefebvre, Daniel D.
Biology

subject:
Phytoremediation
Phytovolatilization
Dioxane
Salix Nigra
Populus Balsamifera
MTBE
Biology

abstract: Thesis (Master, Biology) -- Queen's University, 2010-01-05 15:23:01.288

abstract: Phytoremediation is a viable technology that provides a cost-effective and aesthetically pleasing alternative to traditional remediation technologies. The objective of this study was to compare the effectiveness of Salix nigra and Populus balsamifera in the phytovolatilization of 1,4-dioxane. In the growth studies, P. balsamifera had a significantly decreased growth rate in high concentrations of both 1,4-dioxane and ethylene glycol, while S. nigra showed no significant difference. No significant change in growth was noted between the amended and non-amended soil treatments; however S. nigra trees had a significantly larger size in the amended treatment. S. nigra had a higher survival rate than P. balsamifera with survival rates of 71% and 19% respectively. Total tree evapotranspiration rates were significantly higher in S. nigra than P. balsamifera whereas evapotranspiration rates per m2 of leaf surface area showed the opposite trend. Variations in seasonal precipitation were seen to affect evapotranspiration rates. During the dry 2007 season evapotranspiration rates were significantly higher in P. balsamifera and significantly lower in S. nigra. The opposite trend in evapotranspiration rates was observed in the wet 2008 season. Amendment of the soil was seen to significantly increase rates of evapotranspiration in S. nigra. Total tree dioxane removal was significantly greater in S. nigra than P. balsamifera, while the opposite was observed when removal was calculated per m2 of leaf surface area. Seasonal variations in precipitation exhibited the same trend on dioxane removal as was observed with evapotranspiration. Laboratory studies confirmed S. nigra as an effective species at the phytovolatilization of both dioxane and MTBE. In conclusion, S. nigra was a more effective species in field trials than P. balsamifera for both phytocontainment and phytovolatilization.

abstract: M.Sc.


title: Electrokinetic Structuring of Catalyst Layers for Polymer Electrolyte Fuel Cells

contributor:
Docoslis, Aristides
Chemical Engineering

subject:
fuel cells
electrokinetics

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2010-01-06 17:29:23.27

abstract: This thesis investigates the possibility of using electrokinetic effects, induced when a colloidal system is subjected to an electric field, to produce deterministic structure in the catalyst layer of polymer electrolyte membrane fuel cells. The susceptibility of the catalyst ink system to electrokinetic effects is clearly demonstrated. A novel apparatus and procedure is developed to allow for the formation of continuous films between two electrode surfaces through solvent evaporation. Characterization of the resulting layers is done through imaging and rotating disc electrode measurements. While the images show some possibility of structure formation, no clear increase in the oxygen reduction rate is observed. Recommendations for extending this work are provided.

abstract: Please restrict for 6 months as per agreement with industrial sponsor

abstract: M.A.Sc.


title: A balancing act between the 'Src-Stat3' and 'p53-caldesmon' pathways dictates the outcome of Src-induced invasive phenotypes

contributor:
Mak, Alan
Biochemistry

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subject:
Cell migration
Cell Invasion
p53
Stat3
Src
caldesmon

abstract: Thesis (Master, Biochemistry) -- Queen's University, 2010-01-09 21:57:30.056

abstract:
Cell migration and invasion are essential physiological processes required for the growth and development of all multicellular organisms. However, they have also been implicated in the pathogenesis of certain vascular system diseases and invasive cancers. In this study, we investigate two proteins involved in cell proliferation and survival signaling, p53 and Stat3, which have been found misregulated in atherosclerosis and cancer, to establish what effect they have on the development of Src-induced invasive phenotypes in aortic vascular smooth muscle cells (VSMC) and NIH 3T3 fibroblasts.
 	In the first stage of this experiment, we investigated the tumor suppressor p53. Once believed to act primarily as a regulator of the cell cycle, DNA repair, senescence and apoptosis, current evidence suggests that p53 can also regulate cell migration and invasion. For our study, we stably transduced VSMC and NIH 3T3 fibroblasts with constitutively active Src (SrcY527F) to generate invasive cell lines with pronounced podosome and rosette formation. We established for the first time that p53 suppresses Src-induced podosome and rosette formation, extracellular matrix degradation, cell migration and invasion in these cells. We also present novel data showing that p53 suppresses these invasive phenotypes, at least in part, by up-regulating the expression of caldesmon, an actin binding protein which stabilizes stress fibers and inhibits podosome and rosette formation.
 	In the second part of this study, we show that Stat3, a pro-survival and pro-metastatic transcription factor, is required downstream of Src for the promotion of invasive phenotypes in VSMC and NIH 3T3 fibroblasts. Interestingly we have also shown for the first time that Stat3 can localize to podosomes and rosettes in these cells. The exact physiological reasoning for this localization, however, remains to be determined.
 	This study provides strong evidence suggesting that mutual antagonism between the anti-invasive ‘p53-caldesmon’ and pro-invasive ‘Src-Stat3’ pathways dictates the outcome of Src-induced invasive phenotypes in VSMC and NIH 3T3 fibroblasts.

abstract: M.Sc.


title: A Bayesian/MCMC Approach to Galaxy Modelling: NGC 6503

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subject:
Galaxy Dynamics
Bayesian Statistics
Galaxy Evolution
N-body Simulations

abstract: Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2010-01-10 00:11:41.946

abstract: We use Bayesian statistics and Markov chain Monte Carlo (MCMC) techniques to construct dynamical models for the spiral galaxy NGC 6503. The constraints include surface brightness profiles which display a Freeman Type II structure; HI and ionized gas rotation curves; the stellar rotation, which is nearly coincident with the ionized gas curve; and the line of sight stellar dispersion, which displays a $\sigma-$drop at the centre. The galaxy models consist of a S\'{e}rsic bulge, an exponential disc with an optional inner truncation and a cosmologically motivated dark halo. The Bayesian/MCMC technique yields the joint posterior probability distribution function for the input parameters, allowing constraints on model parameters such as the halo cusp strength, structural parameters for the disc and bulge, and mass-to-light ratios. We examine several interpretations of the data: the Type II surface brightness profile may be due to dust extinction, to an inner truncated disc or to a ring of bright stars; and we test separate fits to the gas and stellar rotation curves to determine if the gas traces the gravitational potential. We test each of these scenarios for bar stability, ruling out dust extinction. We also find that the gas cannot trace the gravitational potential, as the asymmetric drift is then too large to reproduce the stellar rotation. The disc is well fit by an inner-truncated profile, but the possibility of ring formation by a bar to reproduce the Type II profile is also a realistic model. We further find that the halo must have a cuspy profile with $\gamma \gtrsim 1$; the bulge has a lower $M/L$ than the disc, suggesting a star forming component in the centre of the galaxy; and the bulge, as expected for this late type galaxy, has a low S\'{e}rsic index with $n_b\sim1-2$, suggesting a formation history dominated by secular evolution.

abstract: PhD


title: Design and Evaluation of Efficient Collective Communications on Modern Interconnects and Multi-core Clusters

contributor:
Afsahi, Ahmad
Electrical and Computer Engineering

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subject:
Collective communications
Interconnects

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2010-01-10 21:13:33.249

abstract:
Two driving forces behind high-performance clusters are the availability of modern interconnects and the advent of multi-core systems. As multi-core clusters become commonplace, where each core will run at least one process with multiple intra-node and inter-node connections to several other processes, there will be immense pressure on the interconnection network and its communication system software.
     Many parallel scientific applications use Message Passing Interface (MPI) collective communications intensively. Therefore, efficient and scalable implementation of MPI collective operations is critical to the performance of applications running on clusters. In this dissertation, I propose and evaluate a number of efficient collective communication algorithms that utilize the modern features of Quadrics and InfiniBand interconnects as well as the availability of multiple cores on emerging clusters.
     To overcome bandwidth limitations and to enhance fault tolerance, using multiple independent networks known as multi-rail networks is very promising. Quadrics multi-rail QsNetII network is constructed using multiple network interface cards (NICs) per node, where each NIC is connected to a rail.  I design and evaluate a number of Remote Direct Memory Access (RDMA) based multi-port collective operations on multi-rail QsNetII network. I also extend the gather and allgather algorithms to be shared memory aware for small to medium messages. The algorithms prove to be much more efficient than the native Quadrics MPI implementation.
     ConnectX is the newest generation of InfiniBand host channel adapters from Mellanox Technologies. I provide evidence that ConnectX achieves scalable performance for simultaneous communication over multiple connections. Utilizing this ability of ConnectX cards, I propose a number of RDMA based multi-connection and multi-core aware allgather algorithms at the MPI level. My algorithms are devised to target different message sizes, and the performance results show that they outperform the native MVAPICH implementation.
     Recent studies show that MPI processes in real applications could arrive at an MPI collective operation at different times. This imbalanced process arrival pattern can significantly affect the performance of the collective communication operation. Therefore, design and efficient implementation of collectives under different process arrival patterns is critical to the performance of scientific applications running on modern clusters. I propose novel RDMA-based process arrival pattern aware alltoall and allgather for different message sizes over InfiniBand clusters. I also extend the algorithms to be shared memory aware for small to medium messages under process arrival patterns.  The performance results indicate that the proposed algorithms outperform the native MVAPICH implementation as well as other non-process arrival pattern aware algorithms when processes arrive at different times.

abstract: PhD


title: Beyond the Borders: a teacher’s introspection on transformative pedagogy using critical theory and drama

contributor:
O'Farrell, Larry
Education

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subject:
Drama
Critical Theory

abstract: Thesis (Master, Education) -- Queen's University, 2010-01-11 12:23:08.053

abstract: This thesis explores a pedagogical enquiry that has transformed the way I think and the way I teach. I used a variety of critical and theatre theories to frame my enquiry and for four years consecutively, visited a non-government organization (NGO) in India that uses theatre as an alternate pedagogical tool. I reflected upon the methodological differences between the theatre practices of the NGO and my practices. I then turned my enquiry inward to consider how my learning informed my teaching practices. I then created an alternate theatre project for some students in the American Midwest with Ashok, an artist from India. Ashok spent twelve days training the students in what I refer to as action theatre, while I coordinated, observed and reflected. This theatre is a form of social activism; it is designed to provide a forum for the students to express their socio-political views and raise individual and collective social awareness in the process. After the training period, the students presented a play using these theatre methods. They engaged in discussion with their audience directly after their play. After the training period, Ashok returned to India. He took on the role of mentor and informant to my ongoing enquiry. My enquiry then shifted from an introspective one to a practical one. Some of the students who wished to do so continued creating plays in this fashion. I took over the leadership of the group at their school. A new theatre troupe was created and I used the concepts learned at the NGO and from Ashok in an American suburban context. The theatre troupe created plays for three years. When I moved back to Canada, the troupe stopped its operations. Some students in the group continued activist work using art as a medium by finding other opportunities. I turned my enquiry inward once again to reflect upon how these processes have changed the way I think and the way I teach.

abstract: M.Ed.


title: Local controllability of affine distributions

contributor:
Lewis, Andrew D.
Mathematics and Statistics

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subject:
nonlinear control theory
local controllability
affine distribution
jet bundles
control-affine systems
Lie bracket
high-order tangent vector

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2010-01-11 20:11:45.466

abstract:
In this thesis, we develop a feedback-invariant theory of local controllability for affine distributions.  We begin by developing an unexplored notion in control theory that we call proper small-time local controllability (PSTLC).  The notion of PSTLC is developed for an abstraction of the well-known notion of a control-affine system, which we call an affine system.  Associated to every affine system is an affine distribution, an adaptation of the notion of a distribution.  Roughly speaking, an affine distribution is PSTLC if the local behaviour of every affine system that locally approximates the affine distribution is locally controllable in the standard sense.  We prove that, under a regularity condition, the PSTLC property can be characterized by studying control-affine systems.

The main object that we use to study PSTLC is a cone of high-order tangent vectors, or variations, and these are defined using the vector fields of the affine system.  To better understand these variations, we study how they depend on the jets of the vector fields by studying the Taylor expansion of a composition of flows.  Some connections are made between labeled rooted trees and the coefficients appearing in the Taylor expansion of a composition of flows.  Also, a relation between variations and the formal Campbell-Baker-Hausdorff formula is established.

After deriving some algebraic properties of variations, we define a variational cone for an affine system and relate it to the local controllability problem.  We then study the notion of neutralizable variations and give a method for constructing subspaces of variations.

Finally, using the tools developed to study variations, we consider two important classes of systems: driftless and homogeneous systems.  For both classes, we are able to characterize the PSTLC property.

abstract: PhD


title: Cheating or Coping with Situational Constraints?  How Contemplation and Construal Level Influence Perceptions of Academic Dishonesty and Cheating Behaviour

contributor:
MacDonald, Tara K.
Psychology

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subject:
construal level
morality
academic integrity
cheating

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-01-12 12:56:11.965

abstract: The current program of research investigated factors that influence students’ perceptions of everyday moral violations, as well as their own inclinations to engage in immoral behaviours.  In Experiment 1, I demonstrated that participants’ evaluations of a hypothetical student who contemplated plagiarizing an assignment depended on both the choice that was ultimately made and the length of time spent deliberating about it (cf., Tetlock et al., 2000).  Specifically, when participants were informed that the student ultimately elected to refrain from cheating, the length of time that this individual spent considering the decision had no impact on their subsequent behavioural or character evaluations.  However, when participants were informed that the student had succumbed to the temptation to cheat, they evaluated the individual more harshly if the decision to cheat had been made after a period of deliberation than if the decision had been made blithely, without any forethought.  Experiment 2 extended this program of research by showing that stable and transient variations in construal level interact to influence participants’ perceptions of students who engage in acts of plagiarism.  Specifically, participants with low levels of personal agency evaluated a hypothetical student who had plagiarized an assignment relatively charitably, regardless of how they were prompted to construe the situation.  Furthermore, these participants felt a greater affinity for the student after being induced to construe the student’s actions in low-level terms.  On the other hand, participants with high levels of personal agency who were induced to construe the student’s actions in high-level terms were less positive in their evaluations, and also felt less of an affinity for the student.   Experiment 3 assessed the extent to which stable and transient variations in construal level interact to predict actual cheating behaviour during an evaluative task.  The results of this investigation revealed that priming participants with low levels of personal agency to adopt high-level construals lessened the incidence of cheating among members of this group.  In sum, the results associated with the current program of research suggest that transient shifts in construal level interact with stable levels of personal agency to influence students’ perceptions of peers who engage in academic dishonesty.  Furthermore, they provide evidence that these two factors play a role in the extent to which students behave dishonestly in evaluative settings themselves.  Potential applications that could be derived from the current findings and possible avenues for future research are discussed.

abstract: PhD


title: Data Mining the Genetics of Leukemia

contributor:
Skillicorn, B. David
Computing

format:
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subject:
Data Mining
Acute Lymphoblastic Leukemia

abstract: Thesis (Master, Computing) -- Queen's University, 2010-01-12 18:40:44.2

abstract:
Acute Lymphoblastic Leukemia (ALL) is the most common cancer in children under
the age of 15. At present, diagnosis, prognosis and treatment decisions are made
based upon blood and bone marrow laboratory testing. With advances in microarray
technology it is becoming more feasible to perform genetic assessment of individual
patients as well. We used Singular Value Decomposition (SVD) on Illumina SNP,
Affymetrix and cDNA gene-expression data and performed aggressive attribute se-
lection using random forests to reduce the number of attributes to a manageable
size. We then explored clustering and prediction of patient-specific properties such
as disease sub-classification, and especially clinical outcome. We determined that
integrating multiple types of data can provide more meaningful information than
individual datasets, if combined properly. This method is able to capture the cor-
relation between the attributes. The most striking result is an apparent connection
between genetic background and patient mortality under existing treatment regimes.
We find that we can cluster well using the mortality label of the patients. Also, using
a Support Vector Machine (SVM) we can predict clinical outcome with high accu-racy. This thesis will discuss the data-mining methods used and their application to
biomedical research, as well as our results and how this will affect the diagnosis and
treatment of ALL in the future.

abstract: M.Sc.


title: Bidders’ Behaviour and Theory of Share Auctions with Applications to the Colombian Primary Bond Market

contributor:
Ferrall, Christopher
Economics

format:
608284 bytes
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subject:
Treasury Auctions
Share Auctions

abstract: Thesis (Ph.D, Economics) -- Queen's University, 2010-01-14 11:03:29.635

abstract:
Although most governments sell their bonds through a share auction, little is known about behaviour of bidders in these auctions. This thesis analyzes the literature
on government securities auctions, focusing primarily on structural empirical estimation.
Additionally, it examines bidders behaviour in Colombian government bond auctions during 2007, including the additional sale done after the auction.

The thesis summarizes the different structural methodologies that have been developed to determine what the best auction for a particular case is. It discusses the
advantages and disadvantages of each methodology and explores assumptions and robustness when confronted with data. To make these comparisons more straightforward,
a unified notation is introduced and several methods are applied to the same auctions,
uniform price auctions conducted by the government of Colombia.

abstract: PhD


title: A Polysaccharide Extracted From Sphagnum Moss as Antifungal Agent in Archaeological Conservation

contributor:
Spirydowicz, Krysia
Art Conservation

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subject:
Sphagnum Moss
Polysaccharides
Sphagnan
Preservative Agents
Art Conservation
Antifungal Effect
Archaeology
Arctic
Conservation Waxes

abstract: Thesis (Master, Art Conservation) -- Queen's University, 2010-01-14 15:55:23.779

abstract: On the basis of the well-known preservative properties of Sphagnum moss, a potential opportunity to use moss polysaccharides (Sphagnan) in art conservation was tested. Polysaccharides were extracted from the moss (S. palustre spp.) in the amount of 4.1% of the Sphagnum plant dry weight. All lignocelluloses were removed from this extract as a result of the treatment of the moss cellulose with sodium chlorite. The extracted polysaccharide possessed a strong acidic reaction (pH 2.8) and was soluble in water and organic solvents. The extract was tested on laboratory bacterial cultures by the disk-diffusion method. The antibacterial effect was demonstrated for E. coli and P. aeruginosa (both gram-negative) while Staphylococcus aurelus (gram-positive) was shown to be insensitive to Sphagnum polysaccharides. The antifungal effect of Sphagnum extract was tested by the disk-diffusion method on the spores of seventeen fungal species. These fungi were isolated from ethnographic museum objects and from archaeological objects excavated in the Arctic. Twelve of these isolates appeared susceptible to the extract. The inhibiting effect of the extract was also tested by the modified broth-dilution method on the most typical isolate (Aspergillus spp.). In this experiment, in one ml of the nutritious broth, 40µl of 3% solution of polysaccharides in water killed 10,000 fungal spores in 6 hours. The inhibiting effect was not connected to the acidity or osmotic effect of Sphagnum polysaccharides. As an example of the application of Sphagnum polysaccharides in art conservation, they were added as preservative agents to conservation waxes. After three weeks of exposure of microcrystalline wax to test fungi (Aspergillus spp.), 44% of wax was consumed. When, however, ~ 0.1% (w/w) of Sphagnum extract was mixed with wax, the weight loss of wax was only 4% in the same time interval. On the basis of this study it was concluded that Sphagnum moss and Sphagnum products can be recommended for use in art conservation as antifungal agents.

abstract: M.A.C.


title: Children With Alcohol-Related Neurodevelopmental Disorder or Attention Deficit/Hyperactivity Disorder Differ on Neuropsychological Tasks and Measures of Eye Movement Control

contributor:
Reynolds, James
Neuroscience Studies

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abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-01-15 15:15:47.738

abstract:
Children with alcohol-related neurodevelopmental disorder or attention deficit/hyperactivity disorder differ on neuropsychological tasks and measures of eye movement control. M.Sc. Thesis, Queen’s University, Kingston, Ontario, Canada, January 2010.

Background: Alcohol-related neurodevelopmental disorder (ARND) accounts for the majority of diagnoses associated with prenatal alcohol exposure.  Unfortunately, ARND frequently poses a significant clinical challenge as these patients lack the visible physical characteristics associated with alcohol teratogenicity.  Moreover, the cognitive and behavioural disabilities are complex and overlap with those of attention deficit/hyperactivity disorder (ADHD).  Furthermore, co-morbid ADHD is prevalent in children with prenatal alcohol exposure.  While early and accurate diagnosis provides the best prognosis for those affected, there is a lack of tools for differential diagnosis between these two disorders.  The goal of this study was to test the hypothesis that children with ARND exhibit different performance from children with ADHD on computer-based neuropsychological tests and eye movement tasks.  Methods: Our study group was composed of 42 children with ARND and 31 children with ADHD aged 8-15 years, male and female.  Children completed four tasks selected from the Cambridge Neuropsychological Test Automated Battery (CANTAB®) that provided measures of attention, planning, strategy and spatial working memory.  Subjects also performed pro- and anti-saccade tasks, and eye movements were recorded using a mobile eye-tracking system.  Results: Children with ARND demonstrated elevated decision times on a visual matching test of attention and longer response times on a task of spatial working memory, although the two groups had similar errors scores.  Also, compared to children with ADHD, children with ARND had greater anticipatory errors in both the pro- and anti-saccade tasks.  Conclusion: This study demonstrates that there are measurable differences in executive function and eye movement control between children with ARND or ADHD.  Greater deficits in visuospatial processing in ARND may underlie these differences.  These findings demonstrate that the neurobehavioural phenotypes of children with ARND or ADHD have distinct features, which may be accounted for by differences in the patterns of brain injury underlying these two disorders.

abstract: M.Sc.


title: Paleoecological Reconstruction of the Holocene Fire Regime at Mud Lake, Eastern Ontario, near St. Lawrence Islands National Park

contributor:
Hallett, Douglas
Cumming, Brian F.
Environmental Studies

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subject:
Paleoecology
Paleolimnology
Charcoal
Fire History
Restoration

abstract: Thesis (Master, Environmental Studies) -- Queen's University, 2010-02-01 00:14:00.711

abstract: Wildfire is an ecological disturbance that plays an important role in ecosystem function and interacts with climate and vegetation, relationships that may be altered by ongoing climate change.  Insights from paleoecology can provide context for environmental change, including the natural range of variability.  Here, the Holocene fire history of a small watershed in eastern Ontario, Canada is reconstructed.  A high-resolution macroscopic charcoal series was derived from the lacustrine sediment of Mud Lake, north of Gananoque, Ontario and within the Frontenac Arch.  Analysis of the charcoal record estimates a mean fire-return-interval (FRI) of 175 yr/fire around Mud Lake during the Holocene, and similar mean FRIs during different time periods indicates that it has been a largely stationary fire regime.  The analysis suggests that fire activity may have recently increased, but a lack of documentary fire records for the area leaves this uncertain.  There is no indication that humans have significantly impacted the fire regime, though anthropogenic ignition could have played a role in the area’s recent fires.  The fire regime around Mud Lake does not appear to have shifted in association with major changes in regional vegetation.  Fire activity does correlate with some paleoclimate trends.  The estimated fire frequency decreased around 7500 yr BP, when wetter summers became more common in eastern Canada, and a recent increase in fire frequency would parallel with more frequent incursions of dry and cool air masses into the region.  During other parts of the record, however, the fire activity does not appear to reflect the major climate impacts.  The fire history of Mud Lake is relevant to the ecological management of eastern Ontario’s St. Lawrence Islands National Park and its restoration of a rare, fire-dependent tree species, the pitch pine.  Though predictions vary, this area’s climate may become more favorable to fire through an increase in temperature and a decrease in summer precipitation.  By providing information about the natural variability of fire activity in eastern Ontario, this research can be applied towards setting appropriate management goals during future environmental change.

abstract: M.E.S.


title: The Impact of Clinical Factors and Sociodemographic Variables on Health-Related Quality of Life in Venous Leg Ulceration

contributor:
Harrison, Margaret B.
Nursing

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subject:
Leg Ulcer
Quality of Life

abstract: Thesis (Master, Nursing) -- Queen's University, 2010-01-16 13:11:38.045

abstract:
Leg ulceration negatively affects quality of life (QOL). The relationship between important clinical attributes such as ulcer severity, pain and health related quality of life (HRQL) is poorly understood. The Wilson and Cleary model of Health Related Quality of Life (WC model) is a guiding framework that links clinical measures to QOL.
Thesis Objectives: I describe the relationship between ulcer severity, comorbidity, etiology and pain and HRQL.
Methods: An integrative mixed-methods approach was used: a systematic review of studies that examined the relationship between clinical variables and HRQL or QOL as outlined in the WC model (n=22); a review of studies (n=11) that compared the HRQL of persons with leg ulcers to population normative scores; and, an analysis of the relationship between clinical factors and HRQL in a cohort of 564 persons with venous leg ulcers drawn from two randomized control trials.
Results: There is empirical support for the causal linkages between disease severity, symptoms, function, health perception and QOL that comprise the causal pathway as outlined in the WC model. Venous ulcers are associated with a poor quality of life, and numerous aspects of functioning are impaired, in particular physical function. In 564 individuals with venous ulcers, pain was present in 78.8%. Those younger than 65 years were 1.5 times more likely to be in the higher pain group compared to those 65 and older. Physical HRQL was significantly impaired. Predictors of poor physical HRQL included venous-arterial ulcers, a more severe ulcer, arthritis and a higher level of pain. Poor mental HRQL was associated with the younger age group, a comorbid condition and a higher level of pain. Increasing ulcer duration negatively affected mental state, but the findings were of borderline significance.
Conclusion: The WC model is a clinically useful framework to select variables to represent HRQL and to base hypotheses about causal associations between clinical variables and QOL. Future research should focus on specifying the measurement models to represent disease severity, symptom status and functional status. Clinically the WC model is a useful bedside heuristic to explore the impact on leg ulceration on daily life and wellbeing.

abstract: MNSc.


title: In Search of Minerva's Owl: Canada’s Army and Staff Education (1946-1995)

contributor:
English, Allan
History

subject:
Canadian Military History
Professional Education
Staff College
Canadian Forces
Canadian Army

abstract: Thesis (Ph.D, History) -- Queen's University, 2010-01-18 08:27:04.969

abstract: The intellectual history of the Canadian Army from 1946 to 1995 can be traced through the curriculum utilized by the Canadian Army Staff College and the Canadian Forces College to educate the Canadian Army staff officer in conducting warfare within theatres of war. This body of knowledge was analogous to what today comprises the operational level of war. It is a structured vision of conducting conflict that was reaffirmed and sustained by institutional memory created in the crucible of the Second World War and traces its antecedents to the military operations of the Napoleonic Age.  These ideas were preserved almost unchanged throughout the Cold War until the introduction of operational art in the late 1980s, as a result of United States influence. The ability of the Canadian Army to maintain this professional knowledge, as a coherent, unchanging whole throughout a period buffeted by social and political change indicates the separateness of the military profession within Canada. This arose from the absence of consistent and durable political guidance during the immediate post war era. As a result the use of the Canadian military as an instrument of national power became disjointed. By default, the unifying factor in Canadian defence activities was maintaining relevance within alliances, particularly in supporting the Pax Americana. This influence can be discerned by applying theories of knowledge transmission and change to the Cold War curriculum used to educate Canadian Army staff officers.

abstract: PhD


title: RET receptor activation targets expression of the pleiotropic cytokine interleukin-11

contributor:
Mulligan, Lois M.
Pathology and Molecular Medicine

subject: RET

subject: IL-11

abstract: Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2010-01-20 12:37:55.613

abstract: The RET receptor has diverse roles in development and disease, modulating proliferation, survival, and migration of cells. Ligand-independent constitutively active forms of RET can lead to thyroid neoplasia. Missense mutations are causative agents in multiple endocrine neoplasia type 2 (MEN 2), featuring medullary thyroid carcinoma (MTC), whereas RET fusion oncoproteins generated by gene rearrangements are associated with papillary thyroid carcinoma (PTC). In gene expression screens, interleukin-11 was identified as a RET-responsive gene. We sought to characterize the expression of IL-11 in response to activation of the RET receptor, and determine how IL-11 might contribute to RET-mediated cell behaviours. Analysis of HEK293 cells expressing RET, by qRT-PCR and ELISA, established that activation of wild-type RET, MEN 2- and PTC-associated RET upregulated IL-11 transcription and secretion. RET induction of IL-11 gene expression appears to be affected directly and indirectly, and is dependent on activation of the RAS/ERK1/2 signalling pathway. Examination of thyroid carcinoma cell lines with activated RET indicated that PTC-derived TPC-1 cells express IL-11. Addition of exogenous IL-11 stimulated STAT3 phosphorylation in thyroid cancer cell lines, though IL-11 did not affect the proliferation, adhesion, or survival against anoikis in the cells. Immunohistochemical analyses of human thyroid tissues revealed that RET, IL-11, and IL-11Rα are expressed in thyroid cells of the normal thyroid, MTC and PTC.  Expression of the three molecules was also detected in immune cell infiltrates in PTC.  Although we were unable to confirm that the autocrine IL-11 stimulation might affect the behaviour of thyroid cancer cells, it is likely that IL-11 exerts paracrine immunomodulatory effects, and acts downstream of RET in normal biological processes.

abstract: M.Sc.


title: Sleep Problems, Sleep Hygiene, and Attention-Deficit/Hyperactivity Disorder (ADHD) Symptomatology in Young Adults

contributor:
MacLean, Alistair
Psychology

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subject: ADHD

subject: Sleep Hygiene

subject: Attention-Deficit/Hyperactivity Disorder and Sleep

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-01-20 15:27:40.187

abstract: The purpose of this dissertation was to examine the associations between sleep problems, sleep hygiene and ADHD symptoms in young adults. The first chapter of this dissertation provides an overview of ADHD in adulthood, and a review of the literature that has associated ADHD and sleep problems. This chapter also highlights the need to develop a valid and reliable instrument to assess sleep hygiene. The second chapter presents a manuscript which outlines the development of a new self-report measure of sleep hygiene in young adults. Exploratory and confirmatory factor analyses were used to develop two sleep hygiene scales (substance abuse and poor sleep scheduling) and overall results indicated that the new instrument has sound psychometric properties, as well as good construct and convergent validity. The third chapter presents a manuscript which outlines two empirical studies that examined the associations between sleep problems, sleep hygiene and ADHD symptoms in young adults. Results indicated that young adults with elevated ADHD symptoms reported more sleep problems (specifically insomnia and sleepiness) and poorer sleep hygiene (specifically substance abuse and poor sleep scheduling) than young adults without elevated ADHD symptoms. Young adults with ADHD also reported more sleep problems even after accounting for substance abuse and poor sleep scheduling, suggesting that poor sleep hygiene is not responsible for the sleep problems of young adults with ADHD. The fourth chapter presents a summary of the research findings, as well as a discussion of the methodological limitations and directions for future research.

abstract: PhD


title: Real-time Object Recognition in Sparse Range Images Using Error Surface Embedding

contributor:
Greenspan, Michael A.
Electrical and Computer Engineering

format:
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subject:
Object Recognition
Range Image

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2010-01-24 23:07:30.108

abstract:
In this work we address the problem of object recognition and localization from
sparse range data. The method is based upon comparing the 7-D error surfaces of objects in various poses, which result from the registration error function between two convolved surfaces. The objects and their pose values are encoded by a small set of feature vectors extracted from the minima of the error surfaces. The problem of object recognition is thus reduced to comparing these feature vectors to find the corresponding error surfaces between the runtime data and a preprocessed database.

Specifically, we present a new approach to the problems of pose determination, object recognition and object class recognition. The algorithm has been implemented and  tested on both simulated and real data. The experimental results demonstrate the technique to be both effective and efficient, executing at 122 frames per second on standard hardware and with recognition rates exceeding 97% for a database of 60 objects. The performance of the proposed potential well space embedding (PWSE) approach on large size databases was also evaluated on the Princeton Shape Bench-
mark containing 1,814 objects. In experiments of object class recognition with the Princeton Shape Benchmark, PWSE is able to provide better classification rates than
the previous methods in terms of nearest neighbour classification. In addition, PWSE
is shown to (i) operate with very sparse data, e.g., comprising only hundreds of points per image, and (ii) is robust to measurement error and outliers.

abstract: PhD


title: A Duality in Mammalian Glucocorticoid Signaling

contributor:
Wynne-Edwards, Katherine E.
Biology

format:
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subject:
stress
glucocorticoids
adrenal glands
mammal
fetus

abstract: Thesis (Master, Biology) -- Queen's University, 2010-01-25 10:28:26.307

abstract: I tested a prevalent assumption in glucocorticoid research that states that each species has a dominant glucocorticoid, and cortisol and corticosterone are interchangeable steroids. A comprehensive analysis of historical and current data failed to support this assumption and revealed evidence of drift away from exploration of cortisol and corticosterone as dual, important adrenal products to the exclusive quantification of one, dominant glucocorticoid. Originating approximately 30 years ago, the dominant glucocorticoid/ interchangeability assumption is now portrayed in textbook images used to represent adrenal steroid biosynthesis and is widespread throughout empirical research. Less than 1% of over 50,000 published papers relating to the glucocorticoids have considered the potential for independence in glucocorticoid signaling by quantifying both cortisol and corticosterone within a sample. A dispersed literature shows independent regulation of cortisol and corticosterone, extensive inter-species variation in glucocorticoid concentrations and cortisol: corticosterone ratios and adrenal synthesis of the non-dominant glucocorticoid during early development. We hypothesize that there is a functional duality in glucocorticoid signaling and use mass spectrometry to explore the glucocorticoid profile of the full-term human (n = 125) and guinea pig (n = 28) fetus (both cortisol-dominant species). The sample preparation method yielded poor steroid recoveries (~ 4-28%), which made quantification by mass spectrometry challenging, but in both species corticosterone concentrations were significantly higher in fetal blood compared to umbilical venous or umbilical mixed blood (p < 0.0001), suggesting fetal corticosterone enrichment. Within an individual, cortisol was not an accurate predictor of corticosterone for either species (human, r = 0.001, p > 0.05; guinea pig, r = 0.14, p > 0.05) and our data suggests independent glucocorticoid responses; in humans, cortisol was significantly higher in vaginal deliveries relative to elective Caesarian sections (p < 0.0001) but corticosterone was unaffected. Guinea pig fetal corticosterone was not affected by daily maternal stress during gestation but cortisol was significantly lower in stressed fetuses (p < 0.05). While these preliminary data require further investigation, we conclude that fetuses from the human and guinea pig actively secrete the non-dominant glucocorticoid in late gestation and suggest that there is a functional duality in glucocorticoid signaling.

abstract: M.Sc.


title: The Computation and Visualization of Uncertainty in Surgical Navigation

contributor:
Ellis, Randy E.
Stewart, James
Computing

format:
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subject:
uncertainty analysis
computer-aided surgery
registration
visualization

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2010-01-25 16:33:26.755

abstract:
The subject of this dissertation is the calculation and visualization of intraoperative measurement uncertainty in computer-assisted surgical procedures. Error is the difference between the observed or measured value and the true value (called ground-truth) of a quantity. Uncertainty is the unknown difference between the measured and true values, and exists in the absence of knowledge of ground truth.

If one has an algorithm for computing the ground truth then one can get an accurate estimate of error. However, in computer-assisted surgery, the ground truth is often unknown.  The introduction of error to surgical procedures is inevitable: it cannot be avoided by simply taking very careful measurements, providing more accurate algorithms, or by improving instrument calibration. One can only reduce errors as much as reasonably possible, calculate a reliable estimate of the uncertainty, and provide a meaningful way to convey this uncertainty information to clinicians.

In this dissertation, I demonstrate that the visualization of registration uncertainty improves surgical navigation and that real-time computation of intraoperative measurement uncertainty is possible. In an extensive user study of surgeons and surgical residents, I compare methods of visualizing intraoperative uncertainty and determine that there are several methods of effectively conveying uncertainty in surgical navigation.

abstract: PhD


title: The Effect of Phase Morphology and Volume Fraction of Retained Austenite on the Formability of Transformation Induced Plasticity Steels

contributor:
Pilkey, A. Keith
Boyd, Doug
Mechanical and Materials Engineering

format:
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subject:
steel
TRIP steel
formability
austenite
phase morphology
volume fraction

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2010-01-25 16:36:07.598

abstract:
Transformation induced plasticity (TRIP) steels are a class of steels with exceptional formability properties, due mainly to the presence of meta-stable retained austenite which transforms to martensite under loading, locally hardening the steel.  The volume fraction and mechanical stability of the retained austenite play an important role in producing the high formabilities of TRIP steels.  In this thesis, two separate morphologies of retained austenite, equiaxed versus lamellar, have been produced through thermo-mechanical processing of a single common TRIP steel chemistry.  The sheet formability characteristics of these two microstructures were examined, with varying volume fractions of retained austenite, through uniaxial tensile and in-plane plane-strain (IPPS) testing.

It was found that higher levels of retained austenite produced better formability properties for both microstructures and strain paths.  In uniaxial tension it was seen that the the lamellar microstructure attained higher strains at maximum load, and exhibited more sustained instantaneous n values than the equiaxed structure, despite having a lower volume fraction of retained austenite.

IPPS testing was performed using an optical measurement of local strain and a comparative forming limit based on differences in strain rate between a developing neck and the surrounding material.  It was found that the lamellar microstructure performed better than the equiaxed microstructure for this strain path, achieving higher strains before reaching the comparative forming limit.

abstract: M.A.Sc.


title: Moment Connections of Concrete-Filled Fibre Reinforced Polymer Tubes to Reinforced Concrete Footings

contributor:
Fam, Amir Z.
Civil Engineering

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subject: FRP CFFT

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2010-01-28 16:09:40.606

abstract:
Fiber reinforced polymers (FRPs) are increasingly being accepted in structural engineering applications.  One promising system involves the use of concrete-filled FRP tubes (CFFTs) as bridge piers, columns or piles.  While CFFT members have been extensively studied under various loading conditions, very little attention has been given to their connections to other structural components such as footings and beams.  This study explores two different moment connections for CFFT members, using 13 medium-scale specimens and seven ancillary tests.
The first connection involves embedment of the FRP tube into the concrete foundations during casting.  Five-219 mm diameter (D) precast CFFTs were embedded into 500x500x500 mm concrete foundation each, at different embedment lengths ranging from 0.3D to 1.5D and tested in flexure as cantilevers with 1100 mm spans.  The study showed that the optimal embedment length was 0.73D.  This was essentially the minimum embedment length necessary to produce tension failure of the CFFT member outside the footing, rather than premature bond failure that would otherwise occur at lower loads.  Additionally, six push-through tests were conducted on CFFT stubs embedded into footings.  The average bond strength was found to be 0.75 MPa.
The second connection involved adhesive bonding of hollow FRP tubes to short reinforced concrete circular stubs protruding from concrete footings. The remainder of the tube was then filled with concrete, without the need for shoring.  Four-169 mm diameter FRP tubes were first adhesively bonded onto footings with heavily steel-reinforced concrete stubs varying in length from 0.5D to 2.0D, and tested as cantilevers with 1300 mm spans. The optimal bond length that would lead to flexural failure of the tube just outside the stub, rather than bond failure, was about 1.1D.  Based on this, two additional specimens with 1.5D stubs having varying steel reinforcement ratio (ρ) in the stubs were tested. It was shown that the optimal ρ was 2.5%.  Finally, the effect of low cycle reversed bending fatigue was studied using two additional specimens, including one with a sustained axial load of 15-19% of the CFFT axial capacity.  Remarkable levels of ductility associated with the plastic hinge forming in the stub were observed.

abstract: M.A.Sc.


title: To the Global Village and Back: International Indigenous Rights and Domestic Change in Nicaragua and Ecuador

contributor:
Conaghan, Catherine
Political Studies

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subject:
International indigenous rights
international relations

abstract: Thesis (Ph.D, Political Studies) -- Queen's University, 2010-01-26 01:37:46.203

abstract:
International indigenous rights represent a special category of human rights, offering a potent tool in the community-based defense of indigenous lands and livelihoods. State sovereignty has, however, historically been used to trump indigenous claims.  New transnational advocacy networks have formed to promote and support indigenous rights claims in international law. In the Americas, the Inter-American Court of Human Rights (CIDH) has assumed a lead role in issuing important rulings that validate new international norms for indigenous rights. The challenge, identified in this thesis, is the implementation of these rulings through effective domestic policy.

	To realize effective implementation of international rights, domestic political realties cannot be sidestepped or ignored. This thesis focuses on indigenous property rights in the Americas. These rights are always contentious. Natural resources like oil, minerals and timber attract many powerful interests. There is an urgent need for a careful and systematic investigation into domestic level variables that can either hinder or help norm implementation.

	Even universal human rights present a challenge for state compliance. A number of scholars have explored the problem of human rights norm implementation and identified a number of important variables. These include the domestic structural context, norm salience, material constraints and international influences. This thesis builds on Thomas Risse and Kathryn Sikkink’s Spiral Model of Human Rights Change (1999) by applying it to the specific case of indigenous rights to property in a comparative case study. Beginning with two important IACHR rulings for indigenous property rights, the Sarayaku case in the oil-rich Ecuadorian Amazon and the Awas Tingni case in the mahogany forests of the Caribbean Coast of Nicaragua, the Spiral Model is used to highlight key variables that can impact the process of implementation at the level of the state.

abstract: PhD


title: A Holocene-scale analysis of fire regime using sedimentary charcoal from Little Black Lake, eastern Ontario, Canada

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subject:
Paleoecology
Forest Fire
Eastern Ontario

abstract: Thesis (Master, Environmental Studies) -- Queen's University, 2010-01-31 23:58:09.579

abstract: As part of Parks Canada’s management initiatives, St. Lawrence Islands National Park (SLINP) funded this study to learn more about the natural local fire regime, learn about the risks associated with fire in a changing climate scenario, and to aid in protection efforts of the fire-dependent species Pinus rigida (pitch pine), which is listed provincially as a species at risk.  The study site selected was Little Black Lake (44º 32'45.20" N, 76 º 03'12.06” W), which is ideal because of its small size and isolated watershed.  A 4.5 m Livingston-piston core and a 0.5 m Glew gravity core were extracted from the lake basin.  Charcoal macrofossils >125 µm were quantified at 0.5 cm intervals to produce a high-resolution (14 years) fire record.  A chronology was created for each of the two cores together using a combination of 13 14C dates and 20 210Pb dates to complete a record spanning from 2008 to >11000 Cal yrs BP.  In general, the fire regime appears to be non-stationary with overall low CHAR (charcoal particles per cm2 of sediment per year) throughout the Holocene.  The mean fire return interval for the entire record was on the century scale, at 244 years.  The early- and mid-Holocene show low CHAR and few peaks during a period dominated by spruce and pine.  Contrastingly, the late Holocene shows an increase in CHAR and peaks during hardwood dominance, which may be due to a change in fuel, as suggested by charcoal morphotypes.  A detailed look at the Late Holocene through an analysis of the Glew gravity core, shows a shorter mean fire interval.  Comparisons of the Little Black Lake fire record with other vegetation and charcoal records from this region indicate interactions between climate and changing fuel sources may be explanations for the non-stationarity of the fire regime.  Management steps for St. Lawrence Islands National Park could include continuing small, isolated and infrequent burns and continued monitoring of local Pitch Pine populations provided spatial and temporal heterogeneity are taken into account.

abstract: M.E.S.


title: Still Dying for a Living: Shaping Corporate Criminal Liability After the Westray Mine Disaster

contributor:
Snider, Laureen
Sociology

subject:
corporate crime
corporate criminal liability

abstract: Thesis (Ph.D, Sociology) -- Queen's University, 2010-01-27 11:25:25.434

abstract:
This dissertation critically interrogates the assumptions, agendas and relations of power that shaped Bill C-45, An Act to Amend the Criminal Code (criminal liability of organizations), revisions to the Criminal Code of Canada aimed at strengthening corporate criminal liability. Colloquially referred to as the Westray bill, the legislation was passed in the fall of 2003 in response to the deaths of twenty-six workers at the Westray mine in 1992, a disaster caused by unsafe and illegal working conditions.
Using twenty-three semi-structured interviews with individuals with knowledge and insight into the evolution of Canada’s corporate criminal liability legislation, and transcripts from Canada’s Parliament regarding the enactment of this law, the dissertation critically explores the constitution of corporate criminal liability – the factors that produce legal categorizations of corporate harm and wrongdoing. Of particular interest are the official discourses that shaped conceptualizations of corporate crime and corporate criminal liability and how these discourses correspond to the broader social-political-economic context. Drawing theoretical inspiration from Foucauldian and neo-Marxist (Althusserian) literatures, the dissertation argues that particular legal, economic and cultural discourses shaped, but did not determine, corporate criminal liability in Canada. In turn, these discourses are constitutive of class struggles over the role of the corporate form in extracting surplus labour and accumulating capital, the results of which helped stabilize, reproduce and transform the class-based capitalist social formation.
Overall, the dissertation suggests that the assumptions that animated Canada’s corporate criminal liability legislation and the meanings inscribed in its provisions throw serious doubt on its ability to hold corporations legally accountable for their harmful, anti-social acts. There is little reason to believe that the Westray bill will produce a crackdown on safety crimes, or seriously challenge corporations to address workplace injuries and death. While it will hold some corporations and corporate actors accountable – and thus far it has been the smallest and weakest – the primary causes of workplace injury and death (e.g., the tension between profit maximization and the costs of safety and the relative worth of workers/employees versus owners and investors) will continue.

abstract: PhD


title: Bacterial low temperature survival, ice nucleation proteins and ice-associating polymers

contributor:
Walker, Virginia K.
Biology

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subject:
Ice Nucleation Protein
Antifreeze
Extracellular Polymer Substances
Low Temperature Survival

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2010-01-27 11:47:02.385

abstract:
Microorganisms have developed ways to preserve cellular functions under low temperature conditions using a variety of biochemical adaptations including the modification of ice formation. In order to conduct a limited survey of microbial ice-associating strategies, a bacterial community associated with frost-exposed leaves was assessed by the construction of a 16S rDNA library, followed by the characterization of some isolates. Fifteen different species were identified based on their 16S rDNA. Among these, Pseudomonas syringae J6 had ice nucleation activity (INA), which promoted ice formation close to 0ºC, whereas Erwinia billingiae, Flavobacterium sp. and Sphingobacterium kitahiroshimense inhibited the recrystallization of small ice crystals at temperatures close to melting. The Erwinia billingiae isolate showed adhesive and swarming behaviour, which can be associated with biofilm formation. Visualization using negative staining, transmission electron microscopy and scanning electron microscopy confirmed the presence of flagella in addition to the presence of slimy biofilm architecture in these Erwina billingiae cultures. Subsequent purification of the  extracellular polymeric substance followed by mass spectrometry allowed the identification of a putative outer membrane protein A, which may be involved in the protection of this bacterium to freeze-thaw cycles.
To further explore bacterial ice nucleation activity, an ice nucleation protein was cloned from Pseudomonas borealis, a bacterium originating from tundra soil, using degenerative PCR and chromosome walking. The sequence of the putative ice nucleation protein gene (inaPb) was cloned and expressed in Escherichia coli, and its identification was confirmed in the recombinant cells. Although the INPPb was more divergent than other plant-related bacterial INPs, it retained the highly conserved, repetitive core region. The protein may fold so that it has two flat faces, one for protein-protein interactions and the other for ice binding. Expression of the INPPb coding region fused to jelly fish green fluorescent protein showed a temperature-dependent polarized distribution of the recombinant protein in E. coli.
In summary, results from this thesis suggests that low temperature survival may be associated with a number of ice-associating adaptations including the presence of biofilm formation in Erwina billingiae amongst other bacteria, INA in P. borealis and INA-expressing recombinant E. coli.

abstract: PhD


title: A Framework for Peer-to-Peer Computing in Mobile Ad Hoc Networks

contributor:
Hassanein, Hossam S.
Computing

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subject:
peer-to-peer computing
mobile ad hoc networks

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2010-01-27 12:16:25.352

abstract:
Peer-to-peer (P2P) applications are enormously popular on the Internet. Their uses vary from file sharing to Voice-over-IP to gaming and more. Increasingly, users are moving toward wireless networked devices and wish to continue using P2P applications in these new environments. A mobile ad hoc network (MANET) is an infrastructureless network which allows users to dynamically form a mobile, wireless network. Though P2P and MANETs share some similarities, such as self-organization, dynamism, and resilience to failure, it is necessary to create new P2P algorithms that take advantage of the realities of MANETs. These algorithms must account for the numerous challenges found in these networks, including node mobility, resource constrained nodes, and the necessity of fully distributed algorithms.

In this thesis, we propose a framework for mobile P2P computing in MANETs (P2P-MANETs). Our proposal includes the following components. First, nodes must be able to locate and join the P2P overlay. We therefore propose a fully distributed bootstrapping algorithm in which nodes multicast join requests and cache responses. Next, the overlay peers must form a topology of connections between themselves. We propose a fully distributed topology control heuristic which supports the dynamic nature of the P2P-MANET. It is important that peers contribute to the network by sharing their resources and forwarding traffic for others. We therefore propose a dynamically priced incentive scheme which rewards users for contributing to the network. We also propose a path selection algorithm to allow peers to select how many parts of a file to download from which servers and which paths to satisfy the user's preference for download time and cost. Finally, we propose a content distribution system that allows users to download large files through the use of network coding and multicasting. Each of these components is the first proposed for its respective place in a P2P-MANET architecture. Simulation results show that each of the proposed components achieves the goals set out for it and outperforms the comparison schemes. The results also show that the overlay topology and path selection heuristics provide good approximations compared to the optimal solutions.

abstract: PhD


title: Collaborating for Convergence: Instructional Interventions for Children's Reading of Expository Text

contributor:
Hutchinson, Nancy L.
Education

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subject: reading

subject: struggling readers

subject: instructional interventions

subject: older poor readers

subject: school-university partnerships

subject: university researcher-classroom teacher collaboration

subject: collaborative process

subject: expository text

subject: special education

subject: teacher education

subject: ethnography

subject: curriculum design

subject: differentiated instruction

subject: parallel lessons

subject: inclusion

subject: adaptive teaching

subject: exceptional learners

subject: reading-to-learn

subject: student engagement

subject: professional development

subject: social inclusion

subject: tiered instruction

subject: reading comprehension processes

subject: comprehension-monitoring

subject: metacognition

subject: self-regulated learning

subject: self-efficacy

abstract: Thesis (Ph.D, Education) -- Queen's University, 2010-01-27 15:10:03.202

abstract: There are mounting concerns to ensure that children are prepared for the literacy demands of the 21st century. Reading inability at 9 years of age portends a lifetime of illiteracy for the majority of struggling readers. Given the greater weight placed on expository text from the junior grades onwards, children with reading disabilities become increasingly constrained by their reading deficits, putting them at risk of falling ever further behind their normally achieving peers. This ethnographic study, extending over an 8 month period and finishing on the last day of the school year, targeted older poor readers at the junior level. Less is known about their reading deficits, relative to younger struggling readers. Therefore, the first of three principal objectives aimed to extend understanding of the processes whereby older poor readers interact with expository text by providing a qualitative finer-grained assessment of their particular difficulties than presently exists. The second objective was focused on developing and implementing a cohesive program of research-based interventions that targeted critical requirements of successful interactions with expository text, including the ability to summarize, locate information, and attend to text structure. The third objective involved establishing and describing a collaborative, intensive research partnership with two classroom teachers at the junior level to implement and evaluate research-grounded interventions for their students with reading difficulties, working within the context of the regular classroom. The dual researcher role, as collaborator with the teachers and instigator of the intervention program, shaped a reconfigured model of special education, responsive to a diverse range of student needs and abilities, and situated within a content-rich, challenging curriculum. Parallel lessons afforded the opportunity to tier instruction with increasing intensity for the children with the highest needs. Results showed the critical importance of aggressively promoting self-efficacy, self-regulation, and metacognitve awareness for older struggling readers. As these children’s strategic repertoire increased, so, too, did their comprehension and comprehension-monitoring. Differentiated instruction that was tiered, flexible, and responsive supported social inclusion and social collaboration. Social context and authentic content became interwoven and instrumental in engaging the children, maintaining their motivation and sustaining their commitment to read to learn.

abstract: PhD


title: Activist Art Moving the Artist, Shaping the Work

contributor:
Elliott, Stephen
Education

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subject:
Activist Art
Activism
Political Art
Social Justice
Artistic Collaboration
Artistic Process
Artistic Motivation

abstract: Thesis (Master, Education) -- Queen's University, 2010-01-27 15:59:37.792

abstract: This multiple-case study examined the factors that influence activist artists in the production of their work. Four artists who were well established in their careers took part. The research was designed to gain insight into what motivates artists to become activists. The research methodology was rooted in qualitative hermeneutic phenomenological traditions with a descriptive, interpretative and exploratory approach, using data collected from in-depth interviews. This study sought to explore and synthesize common patterns and similarities of activist artists. Seven themes emerged: identity, place, and personality as style, life experience, world issues, community and change. Regarding activist artists using a variety of what is typically considered “style” to present their work, this study concluded that there are similarities that support the notion that activist artists can be seen as a group.

abstract: M.Ed.