title: The Influence of Romantic Attachment Styles and Imagined Partner Rejection on Female Body Image

contributor:
MacDonald, Tara K.
Psychology

subject:
body image
attachment theory
rejection

abstract: Thesis (Master, Psychology) -- Queen's University, 2010-08-16 20:38:45.836

abstract: The purpose of this research was to examine how attachment style and rejection interact to influence female body image. I hypothesized that women who were high in attachment anxiety would report more negative self-evaluations than women who were low in attachment anxiety. I also hypothesized that this main effect would be qualified by a significant interaction between attachment anxiety and rejection, such that highly anxious women who were rejected would report even more negative self-evaluations than highly anxious women who were not rejected. In Study One, I found that higher levels of attachment anxiety were associated with lower self-evaluations but, contrary to expectations, attachment avoidance and rejection condition interacted to influence self-evaluations. At low levels of avoidance, women in the rejection condition reported significantly higher levels of appearance state self-esteem, body esteem, and trait self-esteem than women in the non-rejection condition. However, at high levels of avoidance, women in the rejection condition reported lower levels of these three constructs than women in the non-rejection condition, although this finding was statistically significant only for appearance state self-esteem. In Study Two, my goal was to replicate and extend these unexpected findings by examining perceived partner regard and public self-awareness as potential mediators of the interaction between avoidance and rejection on self-evaluations. Although a main effect of attachment anxiety was revealed for each of the dependent measures, contrary to Study One and my hypotheses, attachment avoidance and rejection did not interact to influence any of the self-evaluation measures and, thus, no mediational analyses were performed. Importantly, I discovered that even though participants’ mean ratings of their body esteem did not change following the rejection manipulation, the degree to which highly anxious women in the rejection condition associated how they felt about their appearance and how they thought their partner perceived them was significantly stronger than that of highly anxious women in the non-rejection condition and low anxious women in either condition. Explanations for the findings found in Study One and Study Two are discussed and the implications of these findings for future research and promoting a positive body image are considered.

abstract: M.Sc.


title: Saccadic eye movement tasks assess central nervous system dysfunction and cognitive improvements in children with fetal alcohol spectrum disorders

contributor:
Reynolds, James
Neuroscience Studies

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:
fetal alcohol spectrum disorder
saccade
intervention

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-08-17 09:55:59.382

abstract:
Background: The central nervous system (CNS) dysfunction resulting from prenatal alcohol exposure (PAE) is the most debilitating aspect of fetal alcohol spectrum disorders (FASDs). Affected children exhibit numerous cognitive and behavioural deficits which can severely affect quality of life. As the diagnosis of FASDs often requires specially trained physicians, there is a need for sensitive and specific tools that screen PAE-related CNS dysfunction in order to identify individuals who require further consultation. Additionally, objective measures of intervention end-points are critical to assess potential treatments for this population. As saccadic eye movement behaviours reflect the integrity of multiple brain structures, a battery of oculomotor tasks may serve both these functions. This study sought to test the hypothesis that oculomotor performance in FASD would differ from typically developing children and would allow the objective measure of cognitive improvements resulting from a strength-based motor skills intervention. Methods: A cohort of 31 children with FASD, and 31 age- and sex-matched controls completed prosaccade, antisaccade, delayed memory-guided sequential (DMS) and predictive eye movement tasks. Additionally, a selection of these children were involved in an intervention study and therefore tested on three separate occasions using the eye movement tasks and computerized neuropsychological tests. Results: Compared to controls, children with FASDs elicited increased direction and anticipatory errors in the antisaccade task, increased timing and sequence errors in the DMS task, and increased anticipatory and decreased express saccades in the predictive task. The FASD group also exhibited an increase in the error of saccade trajectories in the pro- and antisaccade tasks, in addition to increased velocities of
visually-guided saccades in the predictive task. Furthermore, those involved in the intervention study improved in measures of response inhibition in the DMS task. Conclusion: This study indicates that frontostriatal and cerebellar dysfunction can be assessed in children with FASDs using a battery of eye movement tasks. In addition, children involved in the strength-based motor skills intervention improved in the ability to perform complex oculomotor tasks. These findings suggest that select eye movement tasks may be utilized to identify CNS dysfunction in FASD and to measure cognitive improvements resulting from behavioural interventions.

abstract: M.Sc.


title: Relationship threat and self-regulation: The moderating effect of attachment anxiety

subject:
relationship threat
self-regulation
attachment anxiety

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-08-17 21:23:46.461

abstract:
Integrating research on attachment anxiety, rejection, self-regulation and health behaviours, I investigated the interactive effect of attachment anxiety and relationship threat on self-regulation. I hypothesized that self-regulation would decrease following a threat to one’s romantic relationship. Moreover, I expected that this association would be moderated by attachment anxiety, such that it would be stronger for individuals high, relative to low, in attachment anxiety. In three laboratory experiments, relationship threat was made salient and participants were given the opportunity to consume snack foods. In a non-experimental diary study, participants’ relationship stress and health behaviours were measured for a period of seven days.
	The results for Study 1 indicated that women, but not men, high in attachment anxiety experienced self-regulation failure (i.e., ate more jelly beans) when relationship threat was elicited. In contrast, although women low in attachment anxiety demonstrated the same pattern, it was attenuated and non-significant.
Study 2 was designed to replicate the findings from Study 1 using a more powerful relationship threat manipulation that I hoped would cause a consistent pattern for both genders. Contrary to hypotheses, both men and women high in attachment anxiety experienced increased self-regulation (i.e., ate fewer brownie pieces) in the experimental, compared to the control, condition.
One important difference between these studies was the presence of the partner in the laboratory in Study 2. I hypothesized that this might account for the discrepant findings between these studies and designed Study 3 accordingly, such that participants either participated alone or with their partners. Unfortunately, this study did not reconcile the discrepancies between the first two studies:  Only a main effect of relationship threat on number of jelly beans consumed emerged.
For Study 4, individuals completed questionnaires for seven days that assessed how fluctuations in relationship stress interacted with attachment anxiety to affect health outcomes. Analyses of the same-day and lagged effects demonstrated several significant interactions consistent with the hypotheses.
These four studies provide initial evidence for the interactive effect between attachment anxiety and relationship stress on health outcomes and well-being. Although the findings were inconsistent, two of the studies provided support for my hypotheses.

abstract: PhD


title: Principal Component Analyses of Joint Angle Curves to Examine Lifting Technique

contributor:
Stevenson, Joan M.
Kinesiology and Health Studies

subject:
Lifting Kinematics
Ergonomics
Principal Component Analysis
Personal Lift-Assist Device

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2010-08-18 09:35:19.142

abstract: The objectives of the present body of work were 1) to evaluate the Personal Lift-Assist Device (PLAD) in terms of its effect on lifting technique, interjoint coordination, and whether sex modulates these effects and 2) to explore the use of principal component analysis (PCA) as a method to investigate lifting waveforms. Thirty participants (15M, 15F) completed a freestyle, symmetrical lifting protocol during which three-dimensional kinematics of the ankle, knee, hip, and lumbar and thoracic spine were collected using a two-camera Optotrak 3020 system. There were four testing conditions: a) with and b) without wearing the PLAD; and c) 0% load and d) 10% of maximum back strength load. All data were evaluated using PCA. In the first analysis, the relationship between the PLAD and lifting technique under a loaded condition was explored. Results showed that 8 PCs were significantly different between the PLAD/No PLAD conditions yet there were no significant effects of sex on any of the PCs. It was concluded that wearing the PLAD encourages a lifting technique that is reflective of a squat lift, independent of sex. In the second analysis, the PLAD’s effect on interjoint coordination patterns under both loaded and unloaded conditions was examined using the relative phase angle (RPA). It was found that there were no significant differences between device, sex, or load conditions on any of the PCs retained in the model. A novel approach to enhance interpretability of PCs was developed during this study. Finally, when the PLAD was not worn, male and female differences were further investigated under loaded and unloaded conditions. It was determined that when the load is individualized to personal strength characteristics, sex differences in lifting technique are negligible. This is a contradictory finding from previous research. Overall, the major contributions of this research are: support for the use of the PLAD in industry; the recommendation that load be selected based on individual strength characteristics for lifting research experimental design; the use of PCA as a method to effectively evaluate lifting waveforms; and the development of a novel approach to aid in the interpretation of principal components.

abstract: M.Sc.


title: Study of the Role of the Bed Nucleus of the Stria Termialis D1- and D2-Like Dopamine Receptors in Cocaine Self-Administering Rats

contributor:
Dumont, Eric
Neuroscience Studies

subject:
Bed Nucleus of the Stria Terminalis
Dopamine
SCH-23390
Sulpiride
Quinpirole
Cocaine Self-Administration

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-08-18 10:55:40.328

abstract: Previous studies have suggested the importance of the bed nucleus of the stria terminalis (BST) in modulating drug seeking behaviors.  With heavy reciprocal projections from the BST to various dopamine rich areas (ventral tegmental area (VTA), nucleus accumbens shell (NAc shell), retrorubral nucleus (RR), periaqueductal gray region (PAG)), BST dopamine receptors are indeed an important part of the highly integrated reward system and thus possess sensitivity to pharmacological rewards.  In the present study, the effects of bilateral intracranial injections of the D1- dopamine receptor antagonist SCH-23390 (1.6, 3.2, and 6.4 microgram total bilateral dose) , the D2-dopamine receptor antagonist Sulpiride (3.2 microgram total bilateral dose), and D2- dopamine receptor agonist Quinpirole (3.0 microgram total bilateral dose), administered into the BST immediately prior to self-administration sessions, were examined in both sucrose (180-minute sessions) and cocaine (270-minute sessions) self-administering rats.  Injections of SCH-23390 (3.2 & 6.4 microgram) to the cocaine group significantly reduced the final ratio of operant lever responding (0.75 mg/kg/i.v. injection; progressive ratio schedule of reinforcement (PR); timeout 20 sec); there was no effect of SCH-23390 in the sucrose group.  Injections of Sulpiride (3.2 microgram) to the cocaine group produced a significant attenuation in the final ratio of operant lever pressing, with no effect in the sucrose group.  Injections of Quinpirole, however, resulted in no alternations in both the cocaine and sucrose self-administration group.  These results suggest that both D1 and D2 dopamine receptor activation is occurring in the reinforcement of cocaine, with the possibility that D2 receptors are not as highly activated as the D1 receptors.  This conclusion further implicates the complexity of the neurobiological factors involved in drug addiction and the essential role of the BST in dopamine-facilitated reward reinforcement.

abstract: M.Sc.


title: Exit, Voice, Patience, and Neglect: Young Worker Responses to Occupational Safety Concerns

contributor:
Turner, Nick
Management

subject:
young workers
occupational safety
employee voice
proactive behaviour
Hirschman
turnover intentions
responses to hazardous work
commitment
safety management

abstract: Thesis (Ph.D, Management) -- Queen's University, 2010-08-18 13:19:15.634

abstract:
I conducted four studies that develop and test a safety-specific model of exit, voice, patience, and neglect (EVPN) in the context of young workers’ reactions to declining safety conditions (Hirschman, 1970). In the face of hazardous working conditions, contemplating exiting (i.e., quitting the job) or voicing concerns about the risks (e.g., reporting a safety issue to a supervisor) are proactive responses. Conversely, neglecting safety concerns (i.e., ignoring personal safety in the face of danger) is a passive response. Workers may also choose patience (i.e., taking a wait-and-see approach) about concerns.
	In total, 833 young people participated in four studies. Manuscript 1 (Chapter 5) is a focus group study that explores the types, frequency, temporal patterns, and consequences of the safety-related EVPN behaviours. The results showed (1) most participants favoured patience if and when they have concerns about workplace safety; (2) voice is reserved for serious safety concerns; and (3) exit is very uncommon and only used as a last resort.
	Manuscript 2 (Chapter 6) describes the development of age-appropriate measures for general turnover intentions (i.e., exit), and safety-specific voice, patience, and neglect. The reliability, dimensionality, and validity of these scales are demonstrated over three studies.
	Manuscript 3 (Chapter 7) used an experimental scenario approach in which safety conditions (high vs. low), financial reasons for working (high vs. low), and being injured (injured vs. not injured) are manipulated. The role of participant gender (male vs. female) was also examined. Participants assigned to the injury condition were more likely to exercise patience than those assigned to the non-injury condition. Low quality safety conditions were associated with higher turnover intentions. Finally, females reported higher voice than males.
	Finally, Manuscript 4 (Chapter 8) reports on findings from a short-term longitudinal design meant to replicate and extend the results from the previous studies. Support for Hirschman’s loyalty proposition was also found. Specifically, felt responsibility for improving safety was found to moderate the relationship between organizational loyalty and both exit and voice.
	The final chapter integrates these findings and discusses future research directions as well as implications for public policy, management practice, and theory.

abstract: PhD


title: Validating Complex Program Aims: Constructing a Framework for the Validation of One Teacher Education Program’s Aim to Promote Inclusivity as a Fundamental Pedagogical Principle

contributor:
Klinger, Don A.
Education

subject:
Validity
Educational Program Aims
Assessment
Evaluation
Hermeneutics

abstract: Thesis (Ph.D, Education) -- Queen's University, 2010-08-19 20:41:24.683

abstract:
Educational programs are typically guided by complex overarching aims that demark broad expectations for program graduates. In practice, these aims tend to become operationalized into specific, measurable learning objectives, which form the basis for assessment of student learning. Research suggests that this practice limits the accuracy and validity of overarching program aims and may result in misrepresentation of student competency. This limitation is in part due to the use of traditional assumptions of measurement that operate on a validity of correspondence that is linear, singular, and value-free. Accordingly, through this research, I construct a framework for understanding the validity of complex program aims by drawing on contemporary validity theory.
Specifically, I use an interpretive, argument-based approach to validation to connect, analyse, and evaluate multiple interpretations towards a program’s overarching aims. Methodologically, I draw on hermeneutics to collect validity evidence for the construction of a multiple perspective validity argument. I contend that this framework for validation results in a complex articulation of the quality of program coherence between program users’ interpretations of complex aims and their practices. In this dissertation, I apply this validation framework to one teacher education program and its aim to promote inclusivity as a fundamental pedagogical principle. In doing so, I provide a complex description of the multiple ways inclusivity is interpreted by diverse program users (i.e., senior program administrators, faculty members, and teacher candidates) and through various program structures. Thus in addition to articulating a validity argument for one teacher education program, this work also contributes a framework of inclusivity towards broader educational discourse.

abstract: PhD


title: Impact of Manipulated Perceived Efficacy and Self-Affirmation on Measures of Risk, Efficacy, and Intention

contributor:
Fabrigar, Leandre R.
Psychology

subject:
self-affirmation
perceived efficacy
risk
behavioural intentions

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-08-20 09:56:44.707

abstract: In the developed world, the principal sources of morbidity and mortality are diseases of lifestyle, and one of the central goals of health promotion is the encouragement of risk-reducing behaviour. In a series of 3 studies, the present program of research examined the effect of self-affirmation and manipulated perceived efficacy on perceptions of efficacy, risk perception, and risk-reducing behavioural intentions. Participants were undergraduate students who were randomly assigned to a self-affirmation manipulation (self-affirmation versus no self-affirmation) and a perceived efficacy manipulation (high versus low versus baseline), followed by exposure to negative health risk information (risk of a heart attack or colorectal cancer). Across the 3 studies, factor analyses indicated 3 distinct categories of risk-reducing intentions: intentions associated with maintaining an active lifestyle, seeking medical advice and assessment, and maintaining a healthy diet. There was little evidence that self-affirmation affected efficacy, risk, or intentions. Structural equation modeling and meta-analytic analyses suggested the presence of a suppression effect for risk perception: a manipulation designed to increase perceived efficacy had direct positive effects on risk, but also had indirect negative effects on risk, with measured efficacy acting as a mediator. These analyses also showed that the 3 categories of behavioural intentions had distinct (and often different) antecedents. These results highlight the complexity of variables in health risk behaviour. Implications and future directions are discussed.

abstract: PhD


title: A Multiple Perspective Case Study of a Young Adult With Intellectual Disabilities Participating in a University Class

contributor:
Hutchinson, Nancy L.
Education

subject:
Education
Inclusive
Post-Secondary
Intellectual Disability
Teacher Education

abstract: Thesis (Master, Education) -- Queen's University, 2010-08-20 15:53:32.108

abstract:
In this qualitative study the experience of a young woman with an intellectual disability (ID) auditing a university course was explored from multiple perspectives. This young woman audited a curriculum course in a one-year, after-degree Teacher Education program at an Ontario university. The purpose of this study was to explore the meaning of this experience for the student, her classmates, and her curriculum course instructor. Data were collected at the University from observations of the curriculum course and from interviews with the participants. As well, observations were made at a community-based program that prepares adults with ID to take part in inclusive post-secondary education (IPSE) to provide a description of the preparation of these adults for university experiences. The focal participant attended this program for four months prior to auditing the University course.
Data from interviews with the classmates and the course instructor elicited both positive and negative responses concerning their experiences in the inclusive class. Positive responses include seeing inclusion in practice and coming to know the focal participant on a personal level. Negative responses concern whether or not a curriculum class was the right fit for the focal participant. Interview data from the focal participant show that she overwhelmingly enjoyed her experience auditing the Education course. She saw the interaction with same-age peers as a chance to socialize with these peers and as an opportunity to learn about being independent.

abstract: M.Ed.


title: Deconstructing Attitude Strength: Understanding the Cognitive Structures and Subjective Beliefs Related to Attitudes

subject:
Attitudes
Attitude Strength

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-08-23 10:51:04.52

abstract: The effects of various antecedents to cognitive elaboration on the structural properties and subjective beliefs related to attitude strength were examined in 2 experiments.  Participants read vaccine-related information and received arguments for and against the implementation of a vaccine program for a fictitious virus.  Their ability and motivation to attend to the central merits of the arguments were manipulated using a 2 (high vs. low ability) x 2 (high vs. low motivation) between-participants design, and the effects on 21 attitude- and attitude-strength related outcome variables were observed.  Ability was determined by time pressure (Study 1) and distraction (Study 2), and motivation was determined by personal responsibility (Study 1) and involvement (Study 2).  A meta-analysis of the experiments revealed that whereas none of the structural properties related to attitude strength were affected, all of the subjective beliefs were affected, and ability and motivation had differential effects.  Ability primarily affected beliefs that reflect the validity and consistency of the knowledge base as well as the intensity of the attitude; motivation affected beliefs that reflect the intensity of the attitude and the functional relevance of the attitude object.  As well, ability and motivation interacted on a number of variables, with a consistent pattern emerging: High (vs. low) motivation was associated with increased perceived knowledge, clarity, and accessibility, and decreased ambivalence under low ability; the opposite pattern occurred under high ability.  Overall, this research represents the first systematic and the most comprehensive attempt to determine which strength dimensions are affected by variations in elaboration.  It also provides evidence that the subjective beliefs might operate independent of the structural properties, that various antecedents to elaboration might not be directly interchangeable, and that ability and motivation might have different strength-related outcomes.  Finally, this research demonstrated that when used in tandem, the effects of ability and motivation do not necessarily operate in an additive fashion, but can interact in some previously unforeseen ways.

abstract: PhD


title: Improved Methods for Motion-Compensating and Event-Related Spinal Functional Magnetic Resonance Imaging (fMRI)

contributor:
Stroman, Patrick W.
Neuroscience Studies

subject:
Neuroscience
Spinal Cord
Motion
MRI

abstract: Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2010-08-23 13:35:36.534

abstract:
Functional magnetic resonance imaging (fMRI) has become a widely used technique for non-invasive brain mapping, and methods have now evolved to allow fMRI of the spinal cord (spinal fMRI) as well.  With the goal of improving spinal fMRI, the studies presented herein have investigated potential sources of noise that might limit its sensitivity and reliability.  For example, multiple studies had previously suggested that the majority of structured physiological noise, such as spinal cord motion and cerebrospinal fluid (CSF) flow, appeared to be synchronous with cardiac pulsations.  Therefore, we measured cardiac-related spinal cord motion at various levels along the cord, finding that peak anterior-posterior spinal cord displacements often exceeded 0.5 mm throughout the cervical and upper-thoracic regions.  On the other hand, we found that cord motion throughout the lower-thoracic, lumbar and sacral levels was consistently small.  Based on these findings, we concluded that cord motion is likely to be a significant source of error in spinal fMRI throughout superior, but not inferior, cord regions.

Since all motion measurements were acquired at 24 phases of the cardiac cycle, this also allowed us to determine, and subsequently model, the main components of cardiac-related spinal cord motion.  By then including these terms in a general linear model (GLM) analysis and reanalyzing 100 previously acquired cervical spinal fMRI datasets, we showed that the sensitivity and specificity were improved by 15-20 % and 5-6 %, respectively, over previous spinal fMRI methods.  To push the limits of these improvements, we then carried out the first event-related spinal fMRI study, consistently observing spinal cord responses to 1 s applications of 22 °C thermal stimulation.  By measuring these responses at many different phases, we were also able, for the first time, to characterize the impulse response function of SEEP (signal enhancement by extravascular water protons) contrast in the human cervical spinal cord.

abstract: PhD


title: Relay Selection in Two-Hop Wireless Communications

contributor:
Kim, Il-Min
Electrical and Computer Engineering

subject: Relay selection, two-hop communication, unidirectional, bidirectional, PNC, ANC, TDBC, OSS

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2010-08-23 15:29:50.026

abstract:
Relay communication has been shown to be effective to
extend service coverage and mitigate channel impairments. This thesis focuses on
relay selection (RS) of both unidirectional and bidirectional
relay networks employing the amplify-and-forward (AF)
and decode-and-forward (DF) protocols.

This thesis presents four works on RS in two-hop relay networks.
In the first work, we study opportunistic relaying (OR) and
selection cooperation (SC) in
DF-based unidirectional multi-antennas relay networks.
We first propose two joint relay-and-antenna selection
schemes which combine OR and SC, respectively,
with transmit antenna selection.
For each joint selection scheme,
a single best transmit antenna at the source,
a single best relay,
and a single best transmit antenna at this selected relay
are jointly determined.
Then we derive the outage probabilities,
and show that the two schemes achieve the same outage performance.

In the second work, we study RS with
the physical-layer network coding (PNC)
in DF-based bidirectional relay networks.
By modifying the well-known SC and OR,
we first propose two RS schemes for the PNC network:
SC-PNC and OR-PNC.
Then we derive the outage probability
and diversity order of the SC-PNC.
Finally, we show that the OR-PNC achieves the same outage performance
as the SC-PNC.

In the third work, we study RS with
the analog network coding (ANC) and time division broadcast (TDBC),
in AF-based bidirectional relay networks.
We first consider RS schemes
for the ANC and TDBC protocols
based on a max-min criterion.
Then we derive outage probabilities for the ANC and TDBC protocols.

In the fourth work, we study joint relay-and-source selection
in an AF-based bidirectional relay network.
Since RS and opportunistic source selection (OSS) could individually improve
performance of relay networks,
we propose a joint RS-OSS protocol.
In this network, a best source is selected to transmit data
to the other source with the help of a selected best relay.
Then, we derive the outage probability and
average bit-error rate.

The considered RS schemes and obtained outage probability expressions will help the design of two-hop wireless communications in determining the system parameters such as relay location and the transmission power at each terminal.

abstract: PhD


title: Localization of Human Pelvis Anatomical Coordinate System Using Ultrasound Registration to Statistical Shape Model

contributor:
Abolmaesumi, Purang
Mousavi, Parvin
Fichtinger, Gabor
Electrical and Computer Engineering

subject:
Pelvic Anatomical Coordinate System
Statistical Shape Model
Pelvis
Ultrasound

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-08-23 17:57:24.708

abstract:
Total Hip Replacement (THR) has become a common surgical procedure in recent years, due to the increase in the aging population with hip osteoarthritis. Identifying the proper orientation of the pelvis is a critical step in accurate placement of the femur prosthesis in the acetabulum in THR. The general approach to localize the orientation of the pelvic anatomical coordinate system (PaCS) is to use intra-operative X-ray fluoroscopy in a specialized interventional radiology facility to guide the procedure. Employing intra-operative ultrasound (US) imaging fused with pre-operative CT scan or fluoroscopy imaging was proposed to eliminate the ionizing radiation of intra-operative X-ray to the patient and the need for radiology facilities in the OR.  However, the use of pre-operative imaging exposes patients to accumulative ionizing radiation which is desirable to be eliminated.

In this thesis, I propose to replace pre-operative imaging with a statistical shape model (SSM) of the pelvis which is constructed from CT images of patients. An automatic deformable registration of a pelvis anatomical shape model to a sparse set of 2D ultrasound images of the pelvis is presented in order to localize the PaCS. In this registration technique, a set of 2D slices are extracted from the pelvic shape model, based on the approximate location and orientation of a corresponding 2D ultrasound image. The comparison of the shape model slices and ultrasound images is made possible by using an ultrasound simulation technique and a correlation-based similarity metric. During the registration, an instance of the shape model is generated that best matches the ultrasound data. I demonstrate the feasibility of our proposed approach in localizing the PaCS on four patient phantoms and on data from two male human cadavers. None of the test data sets were included in the SSM generation.

abstract: M.A.Sc.


title: Learning in Burkina Faso: a Cautionary Narrative of Development

contributor:
Luce-Kapler, Rebecca
Education

subject:
narrative
participatory development
Burkina Faso
street children

abstract: Thesis (Master, Education) -- Queen's University, 2010-08-24 16:49:22.151

abstract: The focus of this study is to explore what I, a Canadian educator, can learn about development deriving from my relationship with five Burkinabé street youth and from participating in a development project. Furthermore, this thesis explores the following questions: What are the possibilities and challenges associated with Participatory Development according to my experiences during my project? What can be learned from my development experiences? How can my international “development” experience influence my practice in the Canadian classroom? Two conceptual frameworks have guided this thesis: Narrative Inquiry and Participatory Development. The latter was selected for two reasons; firstly, the non-profit development organization I represented and worked with in Kingston, Ontario strongly believe in working with partner organizations in a participatory fashion. Secondly, I was personally interested in exploring whether a participatory approach could be successful in eliminating the power relationships sometimes present in development work. The former was chosen because it offered the most flexibility in terms of writing design and supported the three levels of narrative: experience, telling, and interpreting (Polkinghorne, 1988). As such, this thesis is a self-study narrative that enabled me to present my story as a young teacher, volunteer and researcher. My research has been shaped by (1) my experiences, (2) stories of others, (3) my experiences with individuals who have impacted my journey, (4) my relationships with five Burkinabé street youth, and (5) finally my learning that took place before, during and after my three month volunteer project. ii My experience of volunteering in Burkina Faso has taught me that development is a complex field that should not be as easily accessible to those whom are inexperienced and unprepared to handle the challenges inherent in development work. My self-study cautions new researchers doing fieldwork abroad, volunteers and non-profit organizations of the possible negative effects such as harming the host community/culture, experiencing culture shock or reverse culture shock and practicing volunteer tourism while claiming to do development.

abstract: M.Ed.


title: Symmetry Transforms, Global Plasma Equilibria and Homotopy Analysis Method

contributor:
Bogoyavlenskij, Oleg I.
Mathematics and Statistics

subject: Mathematics

abstract: Thesis (Master, Mathematics & Statistics) -- Queen's University, 2010-08-24 17:33:50.341

abstract:
Magnetohydrodynamics (MHD) flows and equations have been the focus of a large number of researchers. Here a study of such flows and equations is presented.
The first chapter contains a brief introduction to Homotopy Analysis Method (HAM) along with some other definitions. A detailed example on the application of HAM is also included to further clarify the scheme of the method.
Second chapter deals with a study of symmetry transforms for ideal MHD equations which comes from the work of Bogoyavlenskij [18]. Different properties of such transforms are also discussed which include the infinite-dimensional Abelian group formed by the symmetries, breaking of geometrical symmetries and ball lightning phenomenon.
Next we review the recent work of Bogoyavlenskij [19] to present the derivation of exact plasma equilibria with axial and helical symmetries. Asymptotic and periodic nature of the obtained solutions has also been studied.
The last chapter comprises of my own results and it deals with finding solution to unsteady thin film flow of a magnetohydrodynamic fluid. Governing equations of such flows are often very complex and nonlinear. So, we use Homotopy Analysis Method to find exact solution to such nonlinear equations.

abstract: M.Sc.


title: Sobolev Gradient Flows and Image Processing

contributor:
Mansouri, Abdol-Reza
Mathematics and Statistics

subject:
Partial Differential Equations
Image Diffusion
Gradient Flows
Gradient Descent
Gradient Ascent
Sobolev Spaces
Image Sharpening
Anisotropic Diffusion
Perona-Malik Paradox

abstract: Thesis (Master, Mathematics & Statistics) -- Queen's University, 2010-08-25 10:44:12.23

abstract: In this thesis we study Sobolev gradient flows for Perona-Malik style energy functionals and generalizations thereof. We begin with first order isotropic flows which are shown to be regularizations of the heat equation. We show that these flows are well-posed in the forward and reverse directions which yields an effective linear sharpening algorithm. We furthermore establish a number of maximum principles for the forward flow and show that edges are preserved for a finite period of time. We then go on to study isotropic Sobolev gradient flows with respect to higher order Sobolev metrics. As the Sobolev order is increased, we observe an increasing reluctance to destroy fine details and texture. We then consider Sobolev gradient flows for non-linear anisotropic diffusion functionals of arbitrary order. We establish existence, uniqueness and continuous dependence on initial data for a broad class of such equations. The well-posedness of these new anisotropic gradient flows opens the door to a wide variety of sharpening and diffusion techniques which were previously impossible under L2 gradient descent. We show how one can easily use this framework to design an anisotropic sharpening algorithm which can sharpen image features while suppressing noise. We compare our sharpening algorithm to the well-known shock filter and show that Sobolev sharpening produces natural looking images without the "staircasing" artifacts that plague the shock filter.

abstract: M.Sc.


title: The Bioproduction of L-phenylacetylcarbinol in solid-liquid two phase partitioning bioreactors

contributor:
Daugulis, Andrew J.
Chemical Engineering

subject: L-phenylacetylcarbinol

subject: benzaldehyde

subject: solid-liquid two-phase partitioning bioreactor

subject: polymer beads

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2010-08-26 10:53:38.569

abstract:
Biphasic systems such as two-phase partitioning bioreactors (TPPBs) have been used to alleviate biological inhibition by sequestering inhibitory compounds within an immiscible phase.  The use of solid polymer beads as this auxiliary phase provides a fully biocompatible alternative to commonly used yet potentially toxic organic solvents.  This work focused on the application of solid-liquid TPPBs to the bioproduction of the pharmaceutical precursor L-phenylacetylcarbinol (PAC), a biotransformation which suffers from substrate (benzaldehyde), product (PAC), and by-product (benzyl alcohol) inhibition, and simple strategies to improve TPPB performance in general.
A wide range of commercially available, biocompatible, and non-bioavailable polymers were screened for their affinity for benzaldehyde, PAC, and benzyl alcohol.  Hytrel G3548L demonstrated the highest affinity for all three target compounds and was subsequently used in solid-liquid TPPBs for PAC production.  Using 15% v/v polymer beads, PAC concentration was increased by 104% and benzyl alcohol concentration decreased by 38% over the single phase control. The delivery of benzaldehyde from polymer beads demonstrated only a 6-8% reduction in mass productivity with improved operational simplicity and reduced operator intervention.
The final objective of this work was to independently investigate various aspects of the aqueous phase composition and determine how each factor affects the partition coefficient of benzaldehyde in Hytrel G3548L.  Temperature and pH were observed to have no significant effect on partitioning.  Salt and glucose additions increased the partition coefficient by 173% and 30% respectively compared to RO water, while ethanol was found to decrease the partition coefficient from 44 (±1.6) to 1 (±0.3).  These findings may be applied to solid-liquid TPPBs to increase or decrease partitioning as required, leading to improved bioreactor performance.
This work has successfully shown that with careful polymer selection, solid-liquid TPPBs can be used to increase the productivity of a biotransformation without the associated biocompatibility problems that have sometimes been observed with organic solvents.  The delivery of inhibitory substrate from the polymer phase was successfully accomplished, which is a novel demonstration in the field of solid-liquid TPPBs for biocatalysis.  Finally this work contributes a range of simple strategies to improve the partitioning behavior of solid-liquid TPPBs using the aqueous phase composition.

abstract: M.A.Sc.


title: Cognitive Diversity Routing in Wireless Sensor Networks

contributor:
Ibnkahla, Mohamed
Electrical and Computer Engineering

subject:
Cognitive routing
Wireless sensor network

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-08-25 11:27:09.887

abstract: Energy efficiency and network lifetime are key factors in characterizing wireless sensor networks due to the nodes having a finite and exhaustible source of energy. Due to the nodes limited energy, it is vital to have the node functioning for as long as possible otherwise it will render the technology futile. Transmission is the most energy consuming activity a node undertakes, therefore by decreasing the number of unnecessary transmissions, the energy consumption in the nodes decreases significantly. In order to reduce unnecessary transmissions, energy-efficient data dissemination techniques have been developed to deliver the data using the minimum number of necessary transmissions. The topic of this thesis is to develop a routing protocol that will extend the network lifetime by introducing cognition to routing. Cognitive routing is an approach to make nodes more intelligent by utilizing information from the lower layers and network in order to make more informant decisions. Data from the physical layer can relay important information about the state of the node, its neighbors, and the surrounding environment hence enabling the node to make energy-efficient and aware decisions. The routing protocol formulates an energy profile, a channel profile and a traffic profile in order to make adapted and intelligent decisions. Diversity routing is used to increase the reliability of transmissions in the network to reduce unnecessary transmissions as communication is the primary reason for energy consumption in wireless sensor networks. Combining these two approaches in one protocol allows for cognitive routing to operate based on energy constraints obtained from the lower levels hence optimizing the process yielding a longer network lifetime.

abstract: M.A.Sc.


title: Cdc42-Interacting Protein Family Adaptors Regulate Endocytosis, Membrane Trafficking, Migration, and Invasion in Cancer Cells

contributor:
Craig, Andrew W.
Biochemistry

subject:
Cancer Cell Biology
F-BAR Proteins

abstract: Thesis (Ph.D, Biochemistry) -- Queen's University, 2010-08-25 11:44:46.934

abstract: Timely and spatially controlled endosomal trafficking and signaling is important for cell proliferation, directed cell migration, and cell invasion, which are frequently misregulated in cancer cells.  Cdc42-interacting protein-4 (CIP4) family adaptors promote endocytosis by inducing membrane invaginations via their Fer/CIP4 Homology-Bin/Amphyphysin/Rvs (F-BAR) domains, coupled with activation of the actin assembly machinery to promote vesicle fusion or motility.  My thesis focuses on defining the roles of CIP4, and a related protein, Transducer of Cdc42-mediated actin assembly-1 (Toca-1), in regulating Epidermal Growth Factor Receptor (EGFR) endocytosis, EGFR trafficking, cancer cell motility, and invasion.  In Chapter 2, I show that CIP4 and Toca-1 localize to early endosomes and promote EGFR trafficking from early endosomes to lysosomes for degradation, thus limiting extracellular signal-regulated kinase signaling from early endosomes and proliferation of A431 carcinoma cells.  In Chapter 3, I provide novel evidence that depletion of Toca-1 results in defects in actin-based lamellipodial protrusions that are required for cell motility.  The cause of these defects may relate to altered recruitment of the Abelson-interactor-1 and its effector Wiskott-Aldrich syndrome protein family verprolin-homologous protein to the lamellipodia in A431 cells depleted of Toca-1.  Results in Chapter 4 identify CIP4 as a negative regulator of breast cancer invasiveness downstream of Src protein-tyrosine kinase.  Src is a potent inducer of extracellular matrix (ECM)-degrading structures called invadopodia that function in tissue invasion by cancer cells.  I found that CIP4 is a Src substrate that localizes to Src-induced invadopodia in MDA-MB-231 breast cancer cells.  Interestingly, depletion of CIP4 results in enhanced ECM degradation, invadopodia formation, and invasiveness compared to control cells.  Thus, CIP4 and Toca-1 are multifaceted regulators of EGFR downregulation, EGF-induced cell motility, and Src-induced cell invasion.

abstract: We want the thesis to be restricted to allow the publication of two chapters that are currently under review

abstract: PhD


title: Sexual, relational, and psychological functioning among women with provoked vulvar pain

contributor:
Pukall, Caroline F.
Psychology

subject:
vulvar pain
dyspareunia
provoked vestibulodynia
partners
relationship adjustment
sexual functioning
sexual satisfaction

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2010-08-25 12:02:29.446

abstract:
Provoked vestibulodynia (PVD), or recurrent vulvar pain, is a prevalent condition
among women. Although research has documented that PVD is associated with sexual
problems, little research has systematically examined the intimate relationships of affected women. The general purpose of the current studies was to comprehensively
examine sexual and relationship functioning among women with provoked vulvar pain.
In order to do so, three related studies were conducted. The first study was a systematic review of the literature examining sexual and relationship satisfaction among PVD-affected
women. Secondly, an online study was conducted using both standardized and
qualitative measures to examine sexual, relationship, and psychological functioning
among women with self-reported provoked vulvar pain and their male partners in
comparison to controls. The online study also examined associations between affected
women’s pain and women and partner’s functioning. The final study was a laboratory-based study that included women with PVD and matched control women and examined psychosexual functioning, including sexual and relationship satisfaction, and vestibular pain sensitivity; additionally, this study examined potential associations between women’s pain and self-reported functioning. Overall, these studies suggest that women with provoked vulvar pain experience decreased sexual functioning, sexual satisfaction, and psychological functioning in comparison to control women, and that pain-affected partners experience decreased sexual functioning and sexual satisfaction. The findings also indicate that some aspects of women’s pain experiences are related to their self-reported functioning and to that of their partners. This research has implications for
understanding the potential sexual and relationship consequences associated with
provoked vulvar pain, and is among the first to comprehensively examine affected
partners’ functioning. It is hoped that these studies will contribute novel information to the vulvar pain literature, and that they will encourage future research examining sexual and relationship functioning among women with provoked vulvar pain and their partners.

abstract: PhD


title: Taking Account of Religious Diversity: A Case Study of Quebec's Ethics and Religious Culture Program

subject:
religion
religious
religious diversity
diversity
ethics
religious culture
multiculturalism
education
interculturalism
quebec
deep equality

abstract: Modern liberal democratic nation states are faced with new challenges to their ability to sustain a collective identity among citizens from increasingly diverse ethnic and religious backgrounds. This Master‘s Essay examines questions about the most appropriate ways to take account of religion in a pluralist society, specifically as it relates to the education of young citizens in Canadian public schools. I use the Ethics and Religious Culture program adopted in the province of Quebec, examined through the lenses of a multicultural education model and a model of deep equality, to highlight the place of the study of religion in elementary and secondary education.


title: Exposure to stress during development and the importance of timing: An animal model of early life adversity

contributor:
Menard, Janet L.
Psychology

subject:
early life adversity
animal models of anxiety and depression
neurodevelopment
neuroendocrinology

abstract: Thesis (Master, Psychology) -- Queen's University, 2010-08-25 18:53:24.136

abstract: Clinical and preclinical research both indicate that early life adversities alter sensitivity to stress well into adulthood. Although clinical research identifies infancy, childhood, and adolescence as periods of heightened vulnerability, the majority of preclinical research experiments have examined the enduring impact of stressors delivered either prenatally or prior to weaning.  It was recently shown that exposing rats to intermittent stressors across the childhood/ adolescent period (PD 21-51) increased their behavioural and endocrine sensitivity to stress in adulthood. The purpose of the current project was to determine whether specific developmental periods are differentially sensitive to the lasting effects of intermittent stress. Male and female Long-Evans rats were exposed to three stressors (foot shock, elevated platform exposure, and cold water emersion) two times each, randomly over a twelve day period (childhood: PD 22-33 vs. adolescence: PD 35-46). Age-matched controls were briefly handled on each of the stressor application days. After completion of the stress exposure period, rats were left undisturbed for 27 days and behavioural testing commenced in adulthood.  Intermittent physical stress exposure during the childhood period increased anxiety-like behaviours in adulthood, as indexed by the Elevated-Plus Maze (EPM) and Shock Probe Burying Test (SPBT).   This also increased depression-like behaviour in adult male rats and decreased depression-like behaviour in adult female rats, as indexed by the Forced Swim Test (FST).  Intermittent physical stress exposure in the adolescent period increased open-arm activity, increased burying behaviour and increased immobility in the forced swim test, in both male and female rats.  Stress during either developmental period, failed to alter corticosterone (CORT) reactivity to restraint stress in adulthood.  Thus, it appears that the long lasting behavioural impact of early-life adversity can vary, according to the developmental period the stressors are experienced in, but this is further modified by sex and the type of test used to evaluate adult behaviour.

abstract: M.Sc.


title: Determining the Modulus of Intact Bovine Vertebral Cancellous Bone Tissue: Development and Validation of a Protocol

contributor:
Dumas, Geneviève A.
Mechanical and Materials Engineering

subject: Bone Modulus

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2010-08-26 00:03:49.732

abstract:
Cancellous, or spongy, bone accounts for nearly 80% of the human skeleton’s internal surface area, despite comprising only 20% of its mass.  It is made up of a network of struts and plates that provide lightweight internal support to mammalian bones.  In addition, it often serves as the main interface between the skeletal system and implanted devices such as artificial hips, knees, and fracture fixation devices.  However, hip arthroplasties can succumb to loosening of the implant due to bone resorption, which is thought to be caused by a mismatch in both apparent and real stiffness between the device and the surrounding bone.  Many studies have attempted to determine the Young’s modulus of cancellous bone tissue, but the results are far from being in agreement.  Reported values range from less than 1 to nearly 20 GPa.  In addition, the small size of trabeculae has made dissection and testing a challenge.
	In this thesis, whole individual trabeculae from a bovine lumbar spine were tested in three-point bending to determine their Young’s modulus using custom-made equipment to fit a miniature single-axis testing device.  The device itself was validated by testing materials with moduli ranging from 1 to 200 GPa.  The structure of the cancellous bone and the morphology of the individual struts were determined using micro x-ray computed tomography (µXCT).  Individual struts were manually isolated from slices made using a low-speed saw under constant lubrication and measured under a stereomicroscope.  Samples exhibiting no machined surfaces (and thus deemed to be whole, or “uncut”) were compared to struts that had been cut by the saw during sectioning.
	Validation showed that the system was capable of determining the modulus of materials that were approximately five times stiffer than the expected cancellous modulus (copper, at 115 GPa) to within 10% of published values.  This gave confidence in the results for bone.  The modulus of the “uncut” specimens was found to be 15.28 ± 2.26 GPa, while the “cut” specimens had a significantly lower modulus (p = 1.665 × 10-6) at 2.63 ± 2.65 GPa.  The lower modulus for “uncut” specimens may be due to microdamage that occurred during machining and dissection.

abstract: M.A.Sc.


title: How Effective Teachers Differentiate Instruction and Interact With Students Who Engage in Off-task Behaviours in the Classroom

subject:
Off-task behaviour
Differentiated instruction
Effective teachers
Problem behaviour
Student-teacher relationship
Student-teacher interactions

abstract: Thesis (Master, Education) -- Queen's University, 2010-08-26 09:43:54.336

abstract:
The purpose of this study was to discover and describe how two teachers effectively interacted with and differentiated instruction for students who displayed off-task behaviors in the classroom. Through the use of observations and interviews, I described how two teachers interacted with students who display high-frequency, low-intensity off-task behaviors; identified strategies these effective teachers used in dealing with these behaviors; described where the teachers’ behaviours, attitudes, and practices lay on the Preventive-Restorative (P-R) continuum of beliefs of inclusion; and discovered how the teachers’ self-efficacy is related to P-R orientations and effective teaching behaviors.
The teachers were chosen based on their principals’ belief in their effectiveness in dealing with off-task behaviours. The principal and the teacher collaboratively chose the students who displayed off-task behaviours on a consistent basis. The findings of this study confirm the existing research; the two teachers, whose beliefs lay on the preventive end of the continuum of beliefs of inclusion, tended to use effective teaching practices; these beliefs and practices were related to the teachers’ beliefs of their capability in being able to effectively help their students; these two teachers, who have preventive beliefs and high efficacy beliefs, interact in ways that are beneficial to students who display off-task behaviours.
The common themes that emerged through the analysis of both teachers’ data included the belief in and the use of differentiated instruction; the belief in the importance of having a positive classroom environment; the practice of ensuring student engagement; the teachers’ use of their knowledge about students; and the teachers’ beliefs about inclusion and efficacy beliefs. The diversity of the teachers and their classroom contexts resulted in some differences in the findings, which are also discussed.                          This research extends previous research about teachers’ beliefs about inclusion and efficacy beliefs to teaching practices used for and interactions with students who display off-task behaviours. The findings also extend previous research revealing a relationship between teachers’ beliefs about inclusion and the belief in the importance of creating a positive classroom environment. Implications of this research for practice and for future research are discussed.

abstract: M.Ed.


title: Evaluating the Impact of Climate Change Mitigation Strategies on Water Distribution System Design and Optimization

contributor:
Filion, Yves R.
Civil Engineering

subject:
Water Distribution System
Greenhouse Gas Emissions
Optimization
Environmental Impact

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2010-08-26 15:01:27.174

abstract:
In response to growing environmental concerns, policy makers in Canada have been developing climate change mitigation strategies that will enable Canada to meet medium and long-term greenhouse gas (GHG) emission reduction targets. The water industry is energy- and carbon-intensive, thus the magnitude and long-term uncertainty of proposed carbon mitigation policies could have implications for water distribution system capital planning decisions that are made today.

The intent of this thesis was to examine the implications of discount rate and carbon price uncertainty on cost, energy use and GHG emissions in the design/optimization of the Amherstview water distribution system in Loyalist Township, Ontario, Canada. A non-dominated sorting genetic algorithm is coupled with the hydraulic solver EPANET2 in a single-objective optimization approach to identify network expansion designs that minimize total cost as the sum of: i) capital cost of installing new and parallel pipes and of cleaning and lining existing pipes; ii) operation cost of electricity for pumping water; and iii) carbon cost levied on electricity used for pumping water. The Amherstview system was optimized for a range of discount rates and carbon prices reflective of possible climate change mitigation strategies in Canada over the next 50 years. The problem formulation framework was developed according to a “real-world” municipal approach to water distribution system design and expansion. Decision variables such as pipe sizes are restricted to “real-world” commercially-available pipe diameters and parameter values are chosen according to engineering judgment and best-estimates. Parameter uncertainty is characterized by sensitivity analysis rather than the more computationally-demanding and data-intensive Monte Carlo simulation method.  The impact of pipe material selection on energy use and GHG emissions was investigated for polyvinyl chloride and cement-mortar lined ductile iron pipes. Results from this first-ever study indicate that the discount rate and carbon prices investigated had no significant influence on energy use and GHG emissions in the Amherstview system. Pipe material selection was also found to minimally affect the amount of GHG emitted in the Amherstview system.

abstract: M.Sc.


title: The Relationship Between Analyst Coverage and the Distribution of Security Returns

contributor:
Johnson, Lewis
Management

subject:
Stock Returns
Return Distribution
Security Analysts

abstract: Thesis (Ph.D, Management) -- Queen's University, 2010-08-26 12:18:47.528

abstract:
The current study investigates the relationship between analyst coverage and the moments of the return distribution.  Results are presented to support a time-varying pattern in the premiums associated with the higher moments of returns, particularly for the fourth moment of the distribution.  In addition, evidence is presented to suggest that there exists some ex-post and ex-ante forecasting ability based on the use of the higher moments of the return distribution as stock selection criteria.  In the second half of the study, results show that as the number of analysts following a firm increases, the third and fourth moments of the return distribution are impacted, with the former being reduced and the latter increased.  In addition, the initiation and discontinuation of analyst coverage are both found to be related to the higher moments of the return distribution.  The initiation of analyst coverage is associated with a reduction in skewness and an increase in excess kurtosis, while the discontinuation of coverage results in an increase in both of the higher moments of the distribution.
Taken together, the results of the two main questions in the current research study suggest that investors seeking higher distributional moments of returns may favor neglected firms over their followed counterparts, particularly in periods of heightened market volatility.  In addition, the results show that the two main competing hypotheses concerning the causes of non-normal security returns, namely firm information structure and security liquidity, both impact the higher moments of the return distribution.

abstract: PhD


title: A Fully Self-Consistent Constraint on the Mass of M31 and the Local Group

subject:
Physics
Galaxy Astrophysics

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2010-08-27 08:32:52.823

abstract: We present the first fully self-consistent, axisymmetric, dynamical model of the Andromeda galaxy (M31).  We constrain the physical parameters of the model with datasets on all radial scales: the bulge projected velocity dispersion, rotation curve, surface brightness profile, and the kinematics of globular clusters and satellite galaxies.  Combining these highly heterogeneous datasets into a single self-consistent analysis is natural in the framework of Bayesian inference.  Using a geometric argument, we also infer the three-dimensional velocity of M31 relative to the Milky Way.  From this orbit, we constrain the total mass of the Local Group by the ``timing argument''.  We find that the virial mass of M31 is $M_\mathrm{M31,vir} = 5.0^{+2.2}_{-1.7} \times 10^{12} \, M_\odot$ and the mass of the Local Group is $M_\mathrm{LG} = 8.8^{+8.0}_{-4.2} \times 10^{12} \, M_\odot$.  We conclude that the large uncertainties in our results are due primarily to the small sample size at large radii and that either a significantly larger sample or unjustifiably informative priors are necessary to improve the constraint.

abstract: M.Sc.


title: Electrophysiological Characterization of Sodium Currents in Adult Rat Cardiac Myocytes

contributor:
Ward, Christopher Andrew
Redfearn, Damian P.
Physiology

subject:
Cardiac Myocytes
Sodium Currents

abstract: Thesis (Master, Physiology) -- Queen's University, 2010-08-27 10:04:19.043

abstract: The electrical heterogeneity of the heart has been recognized as an important feature of normal cardiac function.  In cardiac myocytes, considerable electrophysiological differences in sodium channel currents have been reported between the atria and the ventricle.  Although, these differences have been primarily attributed to heterogeneous populations of Na+ channel isoforms within cardiac tissue, the link between these electrophysiological differences and certain cardiac pathologies has been loosely studied.  We sought to further elucidate the electrophysiological differences between the atria and the ventricle by characterizing INa in both cell types.  For these studies we had initially predicted the atria to contain a greater density of TTX-sensitive Na+ channel isoforms compared to that of the ventricle.  We used two well-known Na+ channel blockers: lidocaine (100 μM, 30 μM, 10 μM) and tetrodotoxin (TTX; 10 nM, 30 nM).  In addition, we also applied hydrogen peroxide (H2O2; 100 μM, 30 μM, 10 μM) to atrial myocytes, which served as our pathological model for reactive oxygen species (ROS).  When we applied lidocaine to cardiac myocytes, we observed an overall mixed response in both cell types.  Specifically, we noted the most significant differences (p < 0.05) in peak INa, shifts in steady-state inactivation, and impaired recovery from fast inactivation in the presence of 100 μM lidocaine.  Given the non-uniform responses to lidocaine, our results support the theory that tissue specific populations of Na+ channel isoforms exist within cardiac myocytes.  In order to further elucidate the electrophysiological differences between the ventricle and the atria, we applied TTX, which is selective for TTX-sensitive Na+ currents.  Our results indicated no overall significant differences between the ventricle and the atria, suggesting that the population of TTX-sensitive Na+ channel isoforms within the atria specifically, may not be pharmacologically detectable.  Finally, our results also demonstrated that the atria are sensitive to ROS, where H2O2 significantly prolonged the action potential duration (APD) in atrial myocytes.  Our results also suggest that, in addition to INa, other ion channels may be mediating a component of the H2O2-induced prolongation of the APD in adult rat atrial myocytes.

abstract: M.Sc.


title: "Living History" in Canada: Representing Victorian Culture in the Multicultural Present

contributor:
Jessup, Lynda
Art History

subject: Art History

subject: Heritage

subject: Dundurn Castle

subject: Mackenzie House

abstract: Thesis (Ph.D, Art History) -- Queen's University, 2010-08-27 16:45:52.429

abstract: In this study, I investigate the institutional relationship between heritage, living history, and memory in Canadian living history museums, specifically, historic homes that represent Victorian material culture in the contemporary multicultural context.  I consider how historic homes in Canada have been preserved, restored, and constructed as evidentiary – as artefacts for use as civic instruments in the practice and performance of history.  My study connects the artefact to the performance of history at three living history museums which, like so many heritage sites in Canada, taken together deploy “founding nations” mythologies: Dundurn Castle in Hamilton and William Lyon Mackenzie House in Toronto, Ontario, and the Sir George-Étienne Cartier National Historic Site of Canada in Montreal, Quebec. To make this connection, I examine the “Victorian Christmas” program offered annually at each site; the Christmas programs are examples of “living history” in action – period rooms are decorated to represent a historical seasonal celebration, interpreters discuss traditions and activities associated with the occasion, and visitors sing carols and eat festive treats. I explore the implications of institutional interpretations of the past that privilege bi-national mythologies, despite the fact that each site I have chosen is located in the midst of a large urban centre’s ethnically diverse (multicultural) population – and, in the case of the Cartier Houses in Montreal, a constituency informed by contemporary souverainiste issues.

abstract: PhD


title: Opposition et résistance dans la littérature féminine africaine et antillaise

contributor:
Dhavernas, Catherine
Moudileno, Lydie
French

subject: Africa Caribbean Literature Women

abstract: Thesis (Ph.D, French) -- Queen's University, 2010-08-30 13:41:07.321

abstract:
Dans la littérature africaine et antillaise la question des relations de pouvoir est omniprésente. Elle est repérable depuis la littérature des indépendances, qui explorait les enjeux socioculturels lorsque les pays africains et antillais se dégageaient de l’emprise des pouvoirs coloniaux, jusqu'à celle d’aujourd’hui où les pays développés et ceux en voie de développement négocient toujours leur relation avec ces anciens pouvoirs colonisateurs. Alors que la femme noire est la première à ressentir les effets de pouvoir, car doublement marginalisée de ce dernier en tant que femme et noire, elle a historiquement été muselée par un canon littéraire qui ne lui laissait pas de place. Par l’intermédiaire d’une analyse des relations de pouvoir entre la femme noire et l’institution patriarcale, nous dévoilons les tactiques que ces femmes utilisent afin de supporter les systèmes aliénants dans lesquels elles se trouvent : 1) la réhabilitation de leur sexualité 2) la solidarité féminine 3) l’éducation formelle 4) le pouvoir surnaturel et 5) la remise en question des valeurs occidentales.
	A cette fin, nous nous appuyons sur la théorie de l’oppositionnalité de Ross Chambers, mettant en valeur la mise au point sur les modes d’opposition (subtiles) plutôt que sur les modes de résistance (évidents). En récupérant sa sexualité, et une relation saine avec son homologue masculin noir, la femme noire retrouve sa subjectivité et une nouvelle source d’espoir. La solidarité féminine, quant à elle, s’avère nécessaire pour faire reculer l’idéologie et les pratiques qui vont à l’encontre de la femme ; sans elle, la femme n’a pas de moyen de sortir de la domination patriarcale. D’après les romans étudiés, l’éducation formelle est une solution sûre pour la femme de sortir de la misère et de rôles qui limitent ses horizons. Le pouvoir surnaturel, peu étudié jusqu’ici, est un recours problématique pour la femme mais peut la mener à un sens de liberté. Enfin, par la remise en question de valeurs et de jugements occidentaux, les femmes noires assument leur propre image et présentent une version corrective des faits, ce qui est en soi subversif.

abstract: PhD


title: Social Support, Loneliness and Depression in the Elderly

contributor:
Buchanan, Diane
Nursing

subject:
Social Support
Elderly
Loneliness
Depression

abstract: Thesis (Master, Nursing) -- Queen's University, 2010-09-16 20:34:22.965

abstract:
The purpose of this study was to explore specific types of informal social relationships- family or friends formed in nursing homes and to determine how each affected the health of the elderly, especially in the areas of loneliness and depression. A face-to-face interview using four structured questionnaires was adopted for this descriptive study design.
      The main outcomes of depression and loneliness were measured by the Geriatric Depression Scale (GDS) and University of California Loneliness Scale (UCLA). The Duke Inventory Social Support Scale, measuring both family and friend support separately, measured predictor variables of family and friend support. Eighty-seven percent of participants completed the study.
        The results indicate that friend support was a more reliable factor for predicting the levels of loneliness and depression after controlling for all other co-founding variables. The findings will help nurses and other health care personnel when assessing the social support networks, beliefs and preferences of older adults to plan and implement the best practices. This will also offer health care facilities suggested ways to reduce or combat loneliness and depression among the elderly people.

abstract: MNSc.


title: Evaluation of UNK Cell Capacity to Initiate Pregnancy-Associated Spiral Artery Remodelling

contributor:
Croy, B. Anne
Anatomy and Cell Biology

subject:
Uterine Natural Killer Cell
Xenogeneic Engraftment

abstract: Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2010-08-30 16:27:07.522

abstract: Transient uterine Natural Killer (uNK) cells are the predominant leukocytes of early gestational human and murine uteri. Murine uNK cells promote changes in endometrial structure including initiation of perivascular smooth muscle reduction in spiral arteries. Less is known about human uNK cell functions due to sampling constraints. Xenogeneic engraftment of human lymphocyte progenitors to alymphoid mice has been useful in understanding human lymphocyte functions in vivo. Irradiation of recipients is required to create a niche for successful humanization of the mice but renders recipient mice sterile. The goal of my thesis was to develop a protocol enabling engraftment of human hematopoietic stem cells in alymphoid mice that would permit differentiation of functional human uNK cells. I then planned to evaluate human uNK cell functions and their regulation in vivo.  Neonatal Rag2-/-Il2rg-/- mice, which lack T cells, B cells and NK cells were preconditioned with 5-fluorouracil and inoculated with syngeneic mouse bone marrow cells. As adults, inoculated female mice conceived and differentiated functional mouse uNK cells. In contrast, neonatally-preconditioned Rag2-/-Il2rg-/- mice inoculated with human cord blood hematopoietic stem cells conceived but differentiated non-lymphoid cells in sites normally occupied by uNK cells. Weekly injections of human IL-15, which is required for NK cell differentiation, proliferation and survival, did not promote uNK cell differentiation. Rather, treatment with IL-15 altered gestational uteri, even in mice receiving neither preconditioning nor hematopoietic stem cells. I was successful in developing a protocol that enables hematopoietic stem cell engraftment in neonatal mice without compromising mouse fertility. However, this model is apparently not suitable for in vivo studies of human uNK cell functions.

abstract: M.Sc.


title: Process Development for the Production and Separation of Medium-Chain-Length Poly (3-Hydroxyalkanoates) by Pseudomonas Putida KT2440

contributor:
Ramsay, Juliana A.
Ramsay, Bruce A.
Chemical Engineering

subject: Medium-Chain-Length

subject: Poly(3-Hydroxyalkanoates)

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2010-08-30 22:44:44.501

abstract:
A series of medium-chain-length poly(3-hydroxyalkanoates) (MCL-PHAs) with enriched 3-hydroxynonanoate (HN) content (up to 95.8 mol% compared to 68.6 mol% without acrylic acid) or 3-hydroxyoctanoate (HO) content (up to 97.5 mol% compared to 88.0 mol% without acrylic acid) was produced in continuous culture by co-feeding fatty acid and glucose plus inhibiting fatty acid β-oxidation using acrylic acid. Using a similar feeding strategy in fed-batch fermentation, similar monomeric compositions but a higher biomass concentration and PHA content could be obtained. However, at a lower growth rate (0.15 h-1 vs. 0.25 h-1), the biomass concentration and PHA content could be greatly enhanced from 17.1 to 71.4 g L-1 and from 64.4 to 75.5%, respectively, while the HN content decreased slightly from 92.2 to 88.9 mol%. PHAs produced under acrylic acid inhibition possessed improved physical properties including a higher melting point, faster crystallization rate, and greater tensile strength at break and Young’s modulus.
Two recovery methods were developed for the recovery of MCL-PHA from Pseudomonas putida KT2440. One applied acetone extraction which was capable of recovering all the PHA from the cells with a purity of 91.6% and no detectable polymer molecular weight loss using Soxhlet extraction. Further purification was achieved by redissolving in acetone and reprecipitating in cold methanol. The other method used sodium hydroxide to solubilize the non-PHA cellular material. PHA purity of about 85% was obtained from a biomass containing 65.6% PHA after treatment with 0.2 N NaOH at 22 ± 1oC for 2 h or with 0.1 N at 80 ± 1oC for 15 min. However, a treatment at 22 ± 1oC followed by a second NaOH treatment at 80 ± 1oC resulted in higher PHA purity (94.7%) with a recovery efficiency of 88%. Under these conditions, NaOH digestion had a negligible effect on PHA molecular weight.

abstract: PhD


title: System Study and CO2 Emissions Analysis of a Waste Energy Recovery System for Natural Gas Letdown Station Application

contributor:
Peppley, Brant A.
Chemical Engineering

subject:
Direct Internal Reforming Fuel Cell
City Gates Waste Energy Recovery System
Natural Gas Pipeline Transmission
Combined Heat and Power System
Molten Carbonate Fuel Cell
Fuel Cell

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2010-08-31 02:02:11.392

abstract:
A CO2 emission analysis and system investigation of a direct fuel cell waste energy recovery and power generation system (DFC-ERG) for pressure letdown stations was undertaken. The hybrid system developed by FuelCell Energy Inc. is an integrated turboexpander and a direct internal reforming molten carbonate fuel cell system in a combined circle.
At pressure letdown stations, popularly called city gates, the pressure of natural gas transported on long pipelines is reduced by traditional pressure regulating systems. Energy is lost as a result of pressure reduction. Pressure reduction also results in severe cooling of the gas due to the Joule Thompson effect, thus, requiring preheating of the natural gas using traditional gas fired-burners. The thermal energy generated results in the emission of green house gases. The DFC-ERG system is a novel waste energy recovery and green house gas mitigation system that can replace traditional pressure regulating systems on city gates.
A DFC-ERG system has been simulated using UniSim Design process simulation software. A case study using data from Utilities Kingston’s city gate at Glenburnie was analysed. The waste energy recovery system was modelled using the design specifications of the FuelCell Energy Inc’s DFC 300 system and turboexpander design characteristics of Cryostar TG120. The Fuel Cell system sizing was based on the required thermal output, electrical power output, available configuration and cost. The predicted performance of the fuel cell system was simulated at a current density of 140mA/cm2, steam to carbon ratio of 3, fuel utilization of 75% and oxygen utilization of 30%. The power output of the turboexpander was found to strongly depend on the high pressure natural gas flowrate, temperature and pressure. The simulated DFC-ERG system was found to reduce CO2 emissions when the electrical power generated by the DFC-ERG system replaced electrical power generated by a coal fired plant.

abstract: M.A.Sc.


title: Laser Transmission Welding of Polybutylene Terephthalate and Polyethylene Terephthalate Blends

contributor:
Bates, Philip J.
Zak, Gene
Chemical Engineering

subject:
Chemical Engineering
Polymer
Laser Welding
PBT/PET

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2010-08-31 10:03:42.167

abstract:
Laser Transmission Welding (LTW) involves localized heating at the interface of two pieces of plastic (a laser transparent plastic and laser absorbing plastic) to be joined.  It produces strong, hermetically sealed welds with minimal thermal and mechanical stress, no particulates and very little flash. An ideal transparent polymer for LTW must have: a low laser absorbance to avoid energy loss, a low level of laser scattering so it can provide a maximum energy flux at the weld interface and also have a high resistance to thermal degradation. The objective of the project was to analyze the effect of blend ratios of polybutylene terephthalate and polyethylene terephthalate (PBT/PET) on these laser welding characteristics.
The blends were manufactured by DSM (Netherlands).  They were characterized using Differential Scanning Calorimetry (DSC) and Thermal Gravimetry Analysis (TGA).  The latter technique was used to estimate the order (n), activation energy (ΔH) and frequency factor (A’) of the degradation reaction of the polymer blends.
The normalized power profile of the laser after passing through the transparent polymer was measured using a novel non-contact technique and modeled using a semi-empirical model developed by Dr.Chen.  Adding more PET ratio to the blend, did not change beam profile of the transmitted beam significantly.  Laser welding experiments were conducted in which joints were made while varying laser power and scanning speed. Measuring the weld strength and width showed that the blends containing PET have higher strength in comparison to pure PBT.
The temperature-time profile at the interface during welding was predicted using a commercial FEM code. This information was combined with the degradation rate data to estimate the relative amount of degraded material at the weld interface.  It showed that increasing the ratio of PET in the blend makes it more resistant against thermal degradation which can be one of the reasons the PET containing blends reach higher weld strengths when compared to pure PBT.

abstract: M.A.Sc.


title: Physical Activity, Sedentary Behaviour and Melatonin Among Rotating Shift Nurses

contributor:
Aronson, Kristan J.
Janssen, Ian
Community Health and Epidemiology

subject:
Physical activity
Melatonin
Sedentary behaviour
Shift work

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2010-09-01 11:22:35.915

abstract:
Background: Shift work is associated with increased risk of cardiovascular disease and cancer, where decreased melatonin has been proposed as an intermediate in the causal pathway. The influence of physical activity on melatonin has rarely been studied in an observational setting, and it may be important in mediating the effects of shift work. We aimed to assess the influence of energy expended during physical activity of different intensities on melatonin among rotating shift nurses.  We hypothesized that physical activity before the night shift would lessen the decrease in melatonin production that occurs with exposure to light at night.
Methods: 123 female rotating shift nurses working at Kingston General Hospital were recruited over a one-year period.  Physical activity and sedentary behaviours for each participant were recorded during both a day and a night shift using activity diaries, and analysis was restricted to activities between 3 p.m. and 7 a.m. Concentrations of urinary 6-sulfatoxymelatonin, a melatonin metabolite, in morning void urine samples were analyzed for each shift.
Results: The average age of participants was 41 years, and 60% were overweight or obese (body mass index ≥ 25 kg/m2). An average of 6.9 and 5.2 hours of sleep were reported after the day shift and night shift, respectively. Sedentary behaviours such as standing and television watching accounted for over half of the total reported energy expenditure. During the day shift, energy expended in moderate and vigorous intensity physical activity between 3 p.m. and 7 a.m. was negatively associated with melatonin levels (p=0.024, R2 = 0.09). During the night shift, energy expended in sedentary behaviours was negatively associated with melatonin levels (p=0.008, R2 = 0.03).
Conclusions: Physical activity energy expenditure explains only a small amount of melatonin variation, suggesting that other factors are influencing melatonin production, or that melatonin production is minimally effected by these patterns of physical activity.

abstract: M.Sc.


title: Life Experience of Women with HIV

subject: HIV Women vulnerability

abstract: Thesis (Master, Nursing) -- Queen's University, 2010-08-31 10:23:53.052

abstract:
Rates of female Human Immunodeficiency Virus (HIV) infection continue to rise despite the existence of effective methods of prevention.  What is the fundamental variable acting as a barrier to women’s self-protection? Researchers have suggested that the oppression of women increases their vulnerability to HIV infection, and that the relationship between oppression and HIV infection must be examined to effectively address this public health issue.
The purpose of this research was to gain greater insight into the life experiences of women with HIV, in order to clarify whether or not women with HIV have, indeed, experienced oppression.  Answering this question was necessary prior to the study of the relationships between oppression and subsequent female HIV infection.
	Women, age 18 years of age or older, who live in Canada, are proficient at speaking English and HIV positive were recruited to this phenomenological study and each participant was asked to tell their “life story”.   The findings of this study provide support for the ongoing use of both the oppression framework and feminist perspective in future research.  Future studies may include replication of this study in partnership with women with HIV and other academic/community organizations, as well as further analysis of the use of both the Theory of Gendered Power and Social Dominance Theory/Four Bases of Gendered Power in addressing female vulnerability to HIV.

abstract: MNSc.


title: A candidate gene analysis of response to citalopram and escitalopram treatment in patients with major depressive disorder and generalized anxiety disorder

contributor:
Milev, Roumen
Neuroscience Studies

subject:
depression
anxiety
candidate gene analysis
citalopram
escitalopram

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2010-08-31 12:26:21.402

abstract:
Objective: To determine whether genotype at the catechol-O-methyltransferase rs4680, dopamine D2 receptor rs1800497, serotonin receptor 1A  rs6295 or serotonin transporter 5-HTTLPR single nucleotide polymorphisms is associated with response to citalopram and escitalopram treatment in patients with major depressive disorder and generalized anxiety disorder.

Methods: Twenty one patients with depression or anxiety who were treated with citalopram or escitalopram for greater than one year, and who stopped the medication for a period of time during which their symptoms returned, and upon re-commencing the medication their symptoms were again reduced, were classified as responders. Patients were assessed using the Sheehan Disability Scale and the Quick Inventory of Depressive Symptomology- self report. The control group consisted of 146 healthy participants. Genotype was determined at each of the candidate genes studied: catechol-O-methyltransferase, dopamine D2 receptor, serotonin receptor 1A and serotonin transporter. Chi squared tests were used to compare genotypic and allele frequencies between responders and controls.

Results: There was no significant difference in genotypic or allele frequencies between responders and controls at each of the genes analyzed.

Conclusions: This pilot study suggests that genotype at the catechol-O-methyltransferase, dopamine D2 receptor, serotonin receptor 1A  and serotonin
transporter genes is not associated with response to citalopram and escitalopram treatment in patients with depression and anxiety. A larger sample size, along with a genome-wide scan are needed to identify genetic variants that predict medication response in future patients.

abstract: M.Sc.


title: The Molecular and Behavioural Effects of Glial Modulators Propentofylline and PJ34 in a Rodent Model of Neuropathic Pain

contributor:
Cahill, Catherine M.
Pharmacology and Toxicology

subject:
Neuropathic Pain
Glia
Delta Opioid Receptors
GPCR Trafficking
Propentofylline
PJ34
Glial Inhibitors

abstract: Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2010-08-31 14:45:47.888

abstract:
Neuronal-glial interactions play an important role in the development of neuropathic (NP) pain states. Earlier studies in our laboratory suggest a role for activated glia in morphine-induced delta opioid receptor (DOR) trafficking by altering DOR functional competence. Thus, chronic treatment with the glial inhibitor, propentofylline (PF) blocks the anti-allodynic and anti-hyperalgesic effects of the DOR agonist deltorphin II.  The present study aimed to determine whether NP pain-induced changes in DOR function and trafficking are dependent on glial activation.
The first global aim of this study was to determine the molecular and behavioural effects of glial activation by two glial inhibitors, PF and PJ34 in a model of neuropathic pain.  Glial activation was assessed via changes in specific proteins using fluorescent immunohistochemistry (IHC). Neuropathy-induced c-Fos activation was assessed by IHC and pain hypersensitivity was assessed, including mechanical allodynia and spontaneous pain. The second global aim determined the role of activated glia in changes in neuropathy-induced increases in DOR function and DOR subcellular localization using immunogold IHC and transmission electron microscopy (EM).
Chronic PJ34 attenuated chronic constriction injury (CCI)-induced mircoglial, but not astrocyte activation. Chronic administration of either PF or PJ34 attenuated the CCI-induced increase in c-Fos immunoreactive expression. However, neither drug attenuated CCI-induced mechanical allodynia or spontaneous pain.
Both chronic PF and PJ34 administration in NP animals attenuated the anti-allodynic effects of the DOR-selective agonist deltorphin II, suggesting glial inhibition blocks DOR function. However, chronic PF, but not PJ34, blocked the anti-allodynic effects of another DOR agonist, SNC80.  These data suggest that SNC80 might be targeting a different DOR molecular species that is not affected by factors released from microglia. Finally, EM experiments revealed that chronic PF treatment prevented the CCI-induced increase in DOR trafficking providing a positive correlation between behaviour and receptor localization.
This study suggests that activated glia contribute to changes in DOR function and trafficking in NP pain states.  It also suggests that there is a dissociation between glial inhibition and pain hypersensitivity.

abstract: M.Sc.


title: SAXS and X-ray Crystallography Studies of the Cellulosome from Clostridium thermocellum

contributor:
Jia, Zongchao
Biochemistry

subject:
Cellulosome
X-Ray Crystallography
SAXS

abstract: Thesis (Ph.D, Biochemistry) -- Queen's University, 2010-09-02 02:50:11.12

abstract:
Cellulosomes are the most efficient plant cell wall degradation machines discovered to date. All cellulosomal components contain protein modules connected by linkers of varying lengths, which are predicted to be flexible. Consequently, structural studies of the cellulosome have employed a “dissect and build” strategy, whereby individual modules are studied in isolation with the hope to later model the intact complex. However, representative individual structures are now available for all of the cellulosome modules and many questions still remain. The studies described in this thesis depart from the ‘dissection’ stage and enter the ‘build’ stage of cellulosome structural studies of the cellulosome from Clostridium thermocellum.
We first describe the crystal structure of a heterodimeric complex comprising the type-II cohesin (CohII) from cell surface anchoring protein SdbA and a trimodular C-terminal truncation of the CipA scaffoldin protein containing the ninth type-I cohesin module (CohI9), a linker, the X-module (X), and the type-II dockerin module (DocII). This structure revealed novel intertwining of scaffoldin molecules and extensive reciprocal contacts between the CohI9 and the X-module of another scaffoldin molecule. Sedimentation velocity experiments indicate dimerization also occurs in solution.
We have carried out the crystallization and structural analysis of a heterotrimeric complex containing the CohI9—X-DocII:CohII complex bound to the type-I dockerin module (DocI) from the Cel9D enzyme, which represents the largest cellulosome fragment ever determined. Identical inter-scaffoldin interactions were observed in the heterotrimeric complex structure as were seen in the heterodimeric complex. However, small angle X-ray scattering (SAXS) studies indicate that this dimerization does not occur in solution. The crystal structures and additional SAXS studies reveal flexibility in the CohI9—X linker that is surprisingly restricted to two dimensions. In addition, this structure provides the first evidence of an orientation bias in DocI binding.
Finally, SAXS was used to investigate modular orientations and linker flexibility in several cellulosome fragments. These studies indicate that cellulosomal linkers exhibit restricted and in some cases highly restrained flexibility. Specifically, scaffoldin linkers display two dimensional motions, enzymes maintain close contact with their cognate DocI modules, and enzyme positions rotate about 90° relative to neighbouring enzymes on the scaffoldin.

abstract: PhD


title: Lattice Strain Development in Inconel-690 under Bi-axial Compression and Tension

contributor:
Holt, Richard A.
Mechanical and Materials Engineering

subject:
Neutron Diffraction
Elastic-Plastic Modeling
Lattice Strain
Plasticity
Finite Element Analysis

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2010-08-31 16:19:23.331

abstract: Nuclear reactor steam generator tubes, manufactured from Nickel alloys such as Inconel 690 (INC690), are potentially susceptible to failure by Stress Corrosion Cracking where crack initiation may be exacerbated by internal stress fields.  A more comprehensive understanding of this potential failure mechanism was gained via an exploration of a model of INC690’s behaviour under Constrained loading conditions in compression and tension.   An Elasto-Plastic Self-Consistent (EPSC) model was used to predict the lattice stresses and strains resulting from Constrained loading in INC690 for four crystallographic planes.  The internal strain fields generated under such conditions were shown to be markedly different from those developed under Uniaxial loading.  Finite Element Modeling was used to design tensile and compression samples as well as a testing rig that would allow the application of a compressive load along one axis of the specimen with simultaneous constraint along another and free-deformation along the third.  Lattice strain measurements were done for both compressive and tensile loading using Time-Of-Flight neutron diffraction.  The predicted and experimental values showed reasonable agreement; mainly in terms of crystallographic plane interaction and behaviour.  Iterative computer modeling was used to achieve a more realistic depiction of the lattice strains developed. This research allowed for an extension on the Uniaxial findings by examining the material’s behaviour under more complex loading that better approximates steam generator tube operating conditions.

abstract: M.A.Sc.


title: Embryotoxicity of dioxin-like chemicals extracted from American eels (Anguilla rostrata) from the St. Lawrence River System

contributor:
Hodson, Peter
Biology

subject:
embryotoxicity
dioxin-like contaminants
American eel
Japanese medaka

abstract: Thesis (Master, Biology) -- Queen's University, 2010-09-01 09:31:19.466

abstract: The American eel (Anguilla rostrata) has suffered a serious population decline in Lake Ontario since the early 1980s due to a decline in recruitment of juveniles migrating from the Sargasso Sea. This has resulted in the closure of the Lake Ontario fishery in 2004 and its listing as endangered under the Ontario Species at Risk act in June of 2008 in Ontario. Due to their complex life cycle, little is known about eels once they leave their freshwater habitats and migrate to the Sargasso Sea to reproduce. Ocean conditions, habitat destruction, disease, reduced lipid content, over-fishing, physical barriers (hydroelectric dams), and chemical contamination are all possible reasons for recruitment decline and may be acting cumulatively. Maternally derived dioxin-like contaminants (DLCs) accumulated during the growth phase of eels in Lake Ontario are toxic to fish embryos, and embryotoxicity is expressed as a series of malformations known as blue sac disease (BSD). I assessed whether these toxicants are in high enough concentrations in sexually maturing, eels to be embryotoxic to their offspring, as assessed by using Japanese medaka (Oryzias latipes), a surrogate species. Medaka embryos were first injected with 2,3,7,8-tetracholordibenzo-p-dioxin (TCDD) to establish their sensitivity to this test chemical expressed as an 11-day EC50 of 3.79 pg/mg, for the induction of BSD. Medaka embryos were injected with eel extracts and their response compared to the TCDD toxicity curve to assess whether extracts caused developmental problems and to estimate the relative concentration of DLCs. Eel extracts from all collection sites caused no dioxin-like toxicity to Japanese medaka embryos. However, significantly higher toxicity at 10 eeq relative to triolein was found for all extracts with no differences among sites, suggesting the presence of non-dioxin-like toxicants. The low level of maternal tissue contamination by DLCs implied by this bioassay is mirrored in chemical monitoring of persistent organic pollutants in Lake Ontario fish. If correct, the low levels of toxicity of extracts to embryos could contribute to the observed increase of eels entering L. Ontario from 2003 to 2008.

abstract: M.Sc.


title: Deep Ecology and Jainism: A Critical Assessment of Theory and Practice

subject:
Deep Ecology
Arne Naess
Jainism
Non-Violence
Ecology
Environmentalism
Religion
India
Non-Absolutism
Interrelatedness

abstract: Deep ecology distinguishes itself from alternate environmental philosophies by considering ecological issues in term of their broader context. That is, deep ecology takes the socio-cultural issues surrounding environmental destruction into account when considering their appropriate solutions. This comprehensive methodology is based on an eight-fold philosophy, which includes the principles of theoretical pluralism, interconnectivity, and non-violence towards the natural world. Similar principles are found within the Jain tradition of Northern India, and are known as anekāntavāda (non-absolutism), parasparopagraho jīvānām (interrelatedness), and ahimsā (non-violence). This similarity has lent itself to easy comparisons between deep ecology and Jainism, in which Jainism is depicted as a religious tradition with inherent environmental values based on deep ecology principles. Yet, scholars such as Devall, Sessions, and Warwick have written of this correlation have focused only narrowly on Jain doctrine, and disregarded the nuanced understanding and complex representations of the living tradition of Jainism. They have failed to take into account the lived reality of Jain practices in their immediate social and cultural context, and consequently, their conclusions are based off of a limited understanding of Jainism. A more critical analysis of Jain doctrines and deep ecology principles will portray the schismatic differences between Jainism and deep ecology, and present them as distinctive philosophies. Therefore, an orthodox understanding of Jainism does not reflect the ideals of deep ecology as presented in its environmental activist philosophy.