title: Mutual Augmentation of Surveillance Practices on Social Media

contributor:
Lyon, David
Mosco, Vincent
Hand, Martin
Sociology

subject:
Surveillance
Social Media

abstract: Thesis (Ph.D, Sociology) -- Queen's University, 2010-12-31 05:12:00.199

abstract: Social media services like Facebook mark the continued domestication of surveillance technology. Facebook has been remarkably successful at establishing a presence within a variety of social settings, including the interpersonal sphere, the academic sector, and the marketplace. As a platform shared by these spheres, Facebook distributes personal information beyond intended contexts. This research will develop a sociological understanding of individual, institutional, and aggregate surveillance through social networking sites. A series of semi-structured face-to-face interviews with students, university administrators and business employees provides a detailed understanding of surveillance practices on Facebook. Three kinds of surveillance are considered. First, lateral – or peer-to-peer – surveillance refers to interpersonal scrutiny between individuals. Second, institutional surveillance is the scrutiny of key populations by universities and other institutions. Third, aggregated surveillance is used primarily by businesses to study relevant markets. I propose that mutual augmentation exists between individual, institutional, and aggregate forms of surveillance on social media. These three models are situated within the same informational platform. By sharing not only the same information, but also the same interface used to access that information, formerly discrete surveillance practices feed off one another. New personal details, criteria, and searching techniques become common knowledge. Marketers and institutions now benefit from ‘user-generated value’ when individuals exchange relevant information amongst themselves. Likewise, university-age users have adopted new criteria like ‘employability’ and ‘liability’ to assess their peers as well as themselves.

abstract: PhD


title: The Author's Farce: Satiric Agency, Authority, and the Performance of Eighteenth-Century Satire on Film and the Stage

contributor:
Fanning, Christopher
English

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:
Satire
Restoration and 18th-Century Literature
Performance
Film
Theatre

abstract: Thesis (Ph.D, English) -- Queen's University, 2010-12-26 12:59:41.98

abstract:
This dissertation investigates how dramatic performance affects satire, its forms of authorisation, adaptation, and interpretation. Focusing on Restoration and eighteenth-century dramatic satires and film adaptations of eighteenth-century satires, I reassess literary criticism that claims the incommensurability of satire and performance based on a particular understanding of satiric authority as unidirectional and didactic, and therefore incompatible with the multi-dimensional nature of film and theatrical authority. In Chapter One, I establish how satire inquires into the nature of authority itself, exposing its “truths,” disciplinary modalities, and mediations, rather than correcting social behaviour. By putting authorised discourses into conflict, satire renders the contingencies of authority and destabilises its own authority through reflexivity and indirection, which counteract clear communication. Satire then invites multiple readings, even disagreements, instead of imposing consensus or compulsory meaning. In its diffusion and fracturing of perspectives, satire becomes amenable to the multiple agents and conditions of theatre and film performances. The task of satiric film and theatre becomes to “tear the seams” of performance and to apply the same reflexivity that satire applies to other authorities to performance's seamless authorisation in order to pursue its broader inquiry into power and discipline.
In Chapter Two, I focus on the Collier Controversy, a pamphlet war in the late seventeenth century, which debated representations of vice in the theatre. I use the controversy to demonstrate what dramatic satire is not: uniform in intention, exposition, and interpretation. In Chapter Three, I examine Henry Fielding’s dramatic satires from 1730s to further debunk the idea of controlled and controlling relations between satirist and audience. I revise criticism of Fielding’s plays as “anti-theatrical” by demonstrating how his self-reflexive performances produce satiric theatre rather than negate theatrical performance. Chapter Four reviews adaptations of Gulliver’s Travels and here I emphasise the need to combine satiric self-reflexivity in film authorship with critical content in satiric films. In the final chapter, I demonstrate how the mockumentary form used in Michael Winterbottom’s 2005 film adaptation of Tristram Shandy successfully produces satiric effect by questioning the premise of its own authority alongside modes of authority and authorship satirised in Sterne’s book.

abstract: PhD


title: Black in Kingston:  Youth Perspectives on "Blackness" and Belonging in a Small Ontario City

contributor:
Lewis, Magda Gere
Education

subject:
Racial identity
Racism
Ontario
Youth
Police
Education
Blackness
Black youth

abstract: Thesis (Master, Education) -- Queen's University, 2010-12-30 23:08:45.145

abstract:
Within the past decade, two major events raised the national profile of the experiences of black youth and the realities of racism in the city of Kingston, Ontario.  The first event occurred in the spring of 2001 and involved the dramatic “high-risk takedown” by Kingston Police of two innocent black male youths who were wrongly profiled as suspects in an assault case.  The second event involved the subsequent release of a report commissioned by Kingston Police which confirmed that black male youth in Kingston were almost four times more likely to be stopped and questioned by Kingston police than any other racial group (Wortley and Marshall, 2005).
This research, while not addressed to the specifics of racial profiling and policing in Kingston, focuses on the marginalized voices of male and female black youth in Kingston.  Eight youth volunteered to participate in this study.  Participants took part in one-on-one interviews with the researcher and three participated in a follow-up focus group session.  Themes explored in the one-on-one interview and focus group sessions included factors influencing the construction of  black identities within a predominantly white city, the negotiation of friendships and relationships, and interactions with public authorities such as teachers and the police.
This study addresses the various ways in which black youth, male and female, experience life in their city – at home, at school, and in the community – and how they feel their blackness  affects these experiences.  It highlights the perspectives and insights of black Kingston youth. The findings of this research can help us better understand how black identities develop in small Canadian cities, how blackness is policed, and the internal and external “regimes of power” that govern these relations. (Foucault, 1977, p.112).  The study offers a medium by which these voices may be heard and may contribute to long-term community-based anti-racism work in Kingston.

abstract: M.Ed.


title: Abandoning Equity Policy: (Re)membering the Queen's University 1991 Principal's Advisory Committee Report on Race Relations

subject:
Equity
Policy
Anti-racism
Discrimination
Higher Education
PAC Report
Policy Analysis
Discourse Analysis

abstract: Thesis (Master, Education) -- Queen's University, 2011-01-23 23:51:55.526

abstract: “The most dangerous form of ‘white supremacy’ is not the obvious and extreme fascistic posturing of small neo-nazi groups, but rather the taken for granted routine privileging of white interests that goes unremarked in the political mainstream” (Gilbourn, 2005, p.485). This genealogical (Foucault, 1979; 1990) research study interrogates the political nature of universities and their role in the maintenance of racial oppression. Using Queen’s University, Ontario, Canada as a case study, it analyzes and explores the racist historical underpinnings of the institution and the response of the university to incidents of racial discrimination in the early 1990’s— particularly the creation of the 1989 Principals Advisory Committee (PAC) on Race Relations. This work documents and examines the institutional, political, and ideological obstacles in implementing this comprehensive, university-wide anti-racism policy. This research reveals and traces the discourses of racism at Queen’s University. It analyzes how the histories, ideologies, and institutional policy responses toward racism have produced and perpetuated processes that function to control and oppress racialized minorities. The study begins with a chronological analysis of racism at the university and identifies and examines the discursive strategies and techniques that are employed to sustain racist practices. The study concludes with an analysis of qualitative interviews with original members of 1989 Principal’s Advisory Committee on Race Relations who drafted the 1991 Race Relations Report, and captures their reflections on the institutional challenges and obstacles in implementing this monumental anti-racism policy at Queen’s University.

abstract: M.Ed.


title: Monitoring Components by Using Aspects and Contracts in Wrappers

contributor:
Zulkernine, Mohammad
Computing

subject: Wrappers Contracts Aspects Components

abstract: Thesis (Master, Computing) -- Queen's University, 2011-01-02 20:43:16.884

abstract:
The re-usability and modularity of components reduce the cost and complexity of the software design. It is difficult to predict run-time scenarios covering all possible circumstances to ensure that the components are full compatible with the system. Monitoring run-time behaviours of components presents a close view of the component qualities. The existing monitoring approaches either implement applications with built-in monitoring features, or observe the external resource and events to predict the status of the components. In this thesis work, we propose an approach to monitor the run-time behaviours of components with aspect-oriented wrappers and contracts.

We design monitoring wrappers to encapsulate the monitored components. The wrapper has the access to interfaces and properties of the wrapped component. We adopt the methodology of Design by Contract to enforce security policies on component wrappers. The contracts define the mutual obligations of two interacting components. The policies implemented in contracts are woven into component wrappers as separate aspect modules. If the component contains any flaws, the wrappers can monitor the behaviours and prevent failures propagating into the wrapped components and the rest of the system. This approach assures that the system is running in a safe environment with the erroneous behaviours or failures detected appropriately. Secure access between the wrappers guarantees a secure environment for the wrapped components.

We conducted experiments on the run-time monitoring of SQL Injection and Cross Site Scripting attacks. We designed cross-cutting concerns such as logging for components to illustrate monitoring components without
touching the underlying components. Monitoring on access control is also possible and feasible to add as an additional concern and is also demonstrated in the experiments. The results show that the framework is very flexible to impose separate policies as aspects on component wrappers without the modifications of the underlying components.

abstract: M.Sc.


title: The Effect of Gonadotropin Releasing Hormone on Opsin Gene Expression and Spectral Sensitivity in Zebra Cichlid Fish (Metriaclima zebra).

contributor:
Hawryshyn, Craig
Biology

subject:
Cichlid
Electroretinogram
Retina
Opsin
Gonadotropin Releasing Hormone
Vision
Intubation
Implant

abstract: Thesis (Master, Biology) -- Queen's University, 2011-01-05 22:57:11.308

abstract: Sexual selection and the maintenance of species diversity in Lake Malawi cichlid fishes are greatly dependent on optical communication, which is influenced by environmental, physiological and endocrinological factors. The diversity in spectral sensitivity of cichlids has been partially attributed to differences in opsin gene expression, with each species preferentially expressing a subset of seven possible genes. Hormones such as gonadotropin releasing hormone (GnRH) can mediate changes in gene expression and the presence of GnRH immunoreactive fibers and GnRH receptors throughout the retinal layers make it an excellent candidate for mediating changes in visual processes. Effects of exogenous GnRH administration on the visual system of zebra cichlids (Metriaclima zebra) via prolonged release cholesterol implants and intubation was investigated using electroretinogram (ERG) recordings, quantitative real-time RT-PCR and in situ hybridization. Three week and ten week sampling periods were used in the intubation study. No obvious differences in spectral sensitivity were evident when looking at a-wave, b-wave and d-wave components of the ERG waveform in any of the treatment groups. A multiple mechanism model was used to describe the cone mechanisms mediating spectral sensitivity and this analysis showed that the activity of cones was shaped by opponent and non opponent cone interactions based on subsets of five opsin genes previously described in cichlids (SWS1, SWS2b, RH2b, RH2aβ, and RH2aα). Although differences in the spectral sensitivity between control and GnRH-treated fish were not evident on a functional level, there were changes in the gonadosomatic index in the intubation group. Quantitative real-time RT-PCR (qRT-PCR) and in situ hybridization demonstrated that treatment with a synthetic GnRH3 analogue using the oral intubation delivery system resulted in statistically significant changes in opsin gene expression in both three week and ten week treatment groups, specifically the upregulation of RH2b and the downregulation of RH2a opsin genes. Moreover, in situ hybridization analysis showed that the pattern of labeling for the RH2a and RH2b riboprobes corroborated the changes in opsin gene expression found in the qRT-PCR data. In contrast, GnRH treatment using the cholesterol implant delivery system did not result in significant changes in spectral sensitivity or opsin gene expression.

abstract: M.Sc.


title: Dynamics of Bose-Einstein Condensates in Josephson Junctions

subject:
bec
bose-einstein condensation
josephson junctions

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2011-01-10 16:31:43.127

abstract: We numerically solve the Gross-Pitaevskii equation and the Bogoliubov de Gennes equations for a double well potential in order to model the dynamics of a Bose-Einstein condensate in a Josephson junction.  First, the two dynamical regimes of the Josephson junction, that is, Josephson oscillations and self-trapping, are investigated under the application of a large sudden perturbation.  It is found that the Josephson dynamics have a strong dependence on the strength of the interatomic interaction, and we observe the breakdown of the two-mode approximation.  Second, we study the control of the dynamics through the use of a time-dependent, tilted double well potential.  In the context of complete population transfer, the effect of the interactions on the adiabaticity and self-trapping is discussed in terms of a Landau-Zener-like model.  We then explore the splitting of the condensate and the resulting dynamical behaviour by keeping the interaction strength constant, but changing the rate of the tilt sweep.  Lastly, we examine the effect of the tilt sweep rate on the dynamics of population transfer.  We observe a dependence of the self-trapping on the adiabaticity.

abstract: M.Sc.


title: Origins of Genetic Variation and Population Structure of Foxsnakes Across Spatial and Temporal Scales

contributor:
Lougheed, Stephen C.
Biology

subject:
Assignment Test
Ecological Niche Factor Analysis
Conservation
Gene Flow
Genetic Diversity
Isolation by Distance
Isolation by Resistance
Least-Cost Path
Microsatellite DNA
Mitochondrial DNA
Ontario
Phylogeography
Population Genetics
Radio Telemetry
Reptile
Spatial Auto-Correlation
Surface Interpolation

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2011-01-11 10:40:52.476

abstract:
Understanding the events and processes responsible for patterns of within species diversity, provides insight into major evolutionary themes like adaptation, species distributions, and ultimately speciation itself. Here, I combine ecological, genetic and spatial perspectives to evaluate the roles that both historical and contemporary factors have played in shaping the population structure and genetic variation of foxsnakes (Pantherophis gloydi).
First, I determine the likely impact of habitat loss on population distribution, through radio-telemetry (32 individuals) at two locations varying in habitat patch size. As predicted, individuals had similar habitat use patterns, but restricted movements to patches of suitable habitat at the more disturbed site. Also, occurrence records spread across a fragmented region were non-randomly distributed and located close to patches of usable habitat, suggesting habitat distribution limits population distribution.
    Next, I combined habitat suitability modeling with population genetics (589 individuals, 12 microsatellite loci) to infer how foxsnakes disperse through a mosaic of natural and altered landscape features. Boundary regions between genetic clusters were comprised of low suitability habitat (e.g. agricultural fields). Island populations were grouped into a single genetic cluster suggesting open water presents less of a barrier than non-suitable terrestrial habitat. Isolation by distance models had a stronger correlation with genetic data when including resistance values derived from habitat suitability maps, suggesting habitat degradation limits dispersal for foxsnakes.
    At larger temporal and spatial scales I quantified patterns of genetic diversity and population structure using mitochondrial (101 cytochrome b sequences) and microsatellite (816 individuals, 12 loci) DNA and used Approximate Bayesian computation to test competing models of demographic history. Supporting my predictions, I found models with populations which have undergone population size drops and splitting events continually had more support than models with small founding populations expanding to stable populations. Based on timing, the most likely cause was the cooling of temperatures and infilling of deciduous forest since the Hypisthermal. On a smaller scale, evidence suggested anthropogenic habitat loss has caused further decline and fragmentation. Mitochondrial DNA structure did not correspond to fragmented populations and the majority of foxsnakes had an identical haplotype, suggesting a past bottleneck or selective sweep.

abstract: PhD


title: An Investigation of the Deliquescence of Ferricopiapite and the Onset of Deliquescence of Epsomite Crystal Faces of Differing Miller Indices

contributor: Geological Sciences and Geological Engineering

subject: Ferricopiapite Deliquescence Epsomite

abstract: Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-01-11 11:33:03.957

abstract: Deliquescence is the process whereby a solid interacts with a humid atmosphere and begins to dissolve when the partial pressure of H2O in the atmosphere exceeds the partial pressure of H2O at which the solid is in equilibrium at a given temperature.  Deliquescence of sulfate minerals poses a risk to both plant and animal life as metals and acid that are stored in the mineral structure are released.  Detailed solid-solution transition boundaries for sulfate minerals aid in the understanding of acid mine waste behavior in the event of environmental changes.  The deliquescence behaviors of ferricopiapite, melanterite, halite and epsomite have been studied as a function of temperature and relative humidity. A device has been developed to determine the onset of deliquescence as the temperature and/or relative humidity around a sample of sulfate mineral is varied.  Experiments were conducted on several synthetic analogues of minerals. Ferricopiapite was studied as it is the most likely mineral to exhibit this behavior in common acid mine drainage sites where sulfates are present. Because no experimental data exist for the deliquescence of ferricopiapite, in order to properly test the device experiments in which the relative humidity was raised above the deliquescence point and then reversed were conducted using synthetic melanterite and halite for which solid-vapor equilibrium constants for temperature and relative humidity are known.  Results of the reversal experiments for melanterite and halite show that the surface resistivity probe designed for this study accurately determines the onset of deliquescence as predicted by the known solid-liquid-vapor phase diagrams.  The deliquescence of copiapite is not a reversible process as it does not re-precipitate from the liquid created by deliquescence as the relative humidity is lowered.  Epsomite was studied to determine if there was any crystallographic control of the onset of deliquescence between different crystal faces. A significant and consistent difference in the onset of deliquescence was observed between the {111} and {100} faces with the {111} face always being the first to deliquesce as a function of increased relative humidity.

abstract: M.A.Sc.


title: Plasticity of the Rat Thalamocortical Auditory System During Development and Following White Noise Exposure

contributor:
Dringenberg, Hans C.
Neuroscience Studies

subject:
Long-Term Potentiation
Auditory Cortex

abstract: Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2011-01-11 14:53:57.677

abstract: Synaptic plasticity reflects the capacity of synapses to undergo changes in synaptic strength and connectivity, and is highly regulated by age and sensory experience. This thesis focuses on the characterization of synaptic plasticity in the primary auditory cortex (A1) of rats throughout development and following sensory deprivation. Initial experiments revealed an age-dependent decline in plasticity, as indicated by reductions in long-term potentiation (LTP). The enhanced plasticity of juvenile rats appeared to be mediated by NR2B subunits of the N-methyl-d-aspartate receptor (NMDAR), as NR2B antagonist application reduced LTP to adult-like levels in juveniles, yet had no effect in adults. The importance of sensory experience in mediating plasticity was revealed in experiments using white noise exposure, which is a sensory deprivation technique known to arrest cortical development in A1. Notably, adult rats reared in continuous white noise maintained more juvenile-like levels of LTP, which normalized upon subsequent exposure to an unaltered acoustic environment. The white noise-induced LTP enhancements also appeared to be mediated by NR2B subunits, as NR2B antagonists reversed these LTP enhancements in white noise-reared rats. Given the strong influence that sensory experience exerts on plasticity, additional experiments examined the effect of shorter episodes of white noise exposure on LTP in adult rats. Exposure to white noise during early postnatal life appeared to “prime” A1 for subsequent exposure in adulthood, resulting in enhanced LTP. The necessity of early-life exposure was evident, as repeated episodes of white noise in adulthood did not enhance plasticity. In older rats that typically no longer express LTP in A1, pharmacological methods to enhance plasticity were explored. Moderate LTP was observed in older rats with cortical zinc application, which may act through its antagonism of NR2A subunits of the NMDAR. Additionally, current source density and cortical silencing analyses were conducted to characterize the distinct peaks of field postsynaptic potentials recorded in A1, with the earlier and later peaks likely representing thalamocortical and intracortical synapses, respectively. Together, this thesis emphasizes the critical role of sensory experience in determining levels of cortical plasticity, and demonstrates strategies to enhance plasticity in the mature auditory cortex.

abstract: PhD


title: Analysis of Tunnel Liner Response in Squeezing Heterogeneous Rockmasses

subject: Tunnel Squeezing Heterogeneous Liner

abstract: Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-01-14 19:16:42.908

abstract: Squeezing ground in tunnelling is a unique method of failure, typically occurring in ductile rock at depth.  To accommodate this mechanism of failure, liners have been designed such that they reduce in circumference as the support takes on initial load.  Technological development in this area is all the more important for tunnels mined in heterogeneous rockmasses.  Currently, the state of practice is to design support based on a normalised average of the strength parameters of the rock units present in the tunnel face.  Under many configurations of heterogeneity, this approach is perfectly valid, however there are styles and magnitudes of heterogeneity that require deeper analysis.  The purpose of this study is to introduce an empirical relationship between liner response in heterogeneous rockmasses and liner response in the homogenised equivalent.  A suite of parameters that define heterogeneity were numerically modelled, using finite element analysis, such that a comprehensive set of the various permutations was evaluated.  The three styles of heterogeneity that were modelled were chaotic structure, folded structure and laminar structure, these represent common and discrete structures found in alpine regions.  Laminar structure was considered at three orientations, and all structures were considered under hydrostatic and differential stress regimes.  Granularity, or scale, and contrast ratio of units were also varied.  These data were analysed with respect to mean axial thrust, range of axial thrust and range of moment on the liner.  Liner response analysis was also conducted on the case study of St. Martin-la-Porte, an adit to the Lyon-Turin Ferroviaire base tunnel in southern France.  This adit has been excavated in a highly variable, heterogeneous rockmass and provides realistic examples of the nature of heterogeneity present in current tunnelling projects.  Ultimately, three equations were developed to provide preliminary predictions of heterogeneous axial thrust and moment variability from the analysis of homogeneous equivalents.

abstract: M.A.Sc.


title: Advanced Techniques for the Characterization of Hydrided Zirconium Alloy

contributor:
Daymond, Mark R.
Holt, Richard A.
Mechanical and Materials Engineering

subject:
Materials Science
Nuclear Materials
Zirconium
Hydrides

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2011-01-17 20:39:25.621

abstract:
Zirconium alloy pressure tubes are an important component in CANDU nuclear reactors.  During operation these tubes can pick up hydrogen as a result of a corrosion reaction, which can eventually lead to the precipitation of a secondary, brittle zirconium hydride phase.  Hydrides tend to first form at flaws (stress concentrations), and when they fracture can initiate a time-controlled crack growth mechanism known as delayed hydride cracking (DHC).  Since DHC is a known failure mechanism for pressure tubes, and an ongoing concern in the nuclear industry, more fundamental knowledge is required about the behaviour of hydrides precipitated at flaws.  Several approaches were employed in this thesis to better characterize the effects and behaviour of hydrides at such stress concentrations.

High energy X-ray diffraction, as well as in-situ SEM testing coupled with digital image correlation, were used to map the strains around stress concentrations where hydrides were present.  These studies highlighted important differences in the behaviour of the hydride phase and the surrounding zirconium.  To gain greater insight into hydride morphology, neutron tomography was used in an attempt to measure the through-thickness hydride distribution at flaws.  A finite element model was also developed and verified against the X-ray strain mapping results.  This model provided greater insight into details that could not be obtained directly from the experimental approaches, as well as providing a framework for future modeling to predict the effects of hydride precipitation under different conditions.  Taken as a whole, these studies provide important information for improving service guidelines and avoiding conditions that favour embrittlement due to hydride precipitation.

abstract: M.A.Sc.


title: Investigating the Sophistication of Long-Latency Stretch Responses During Postural Control of the Upper Limb

contributor:
Scott, Stephen H.
Neuroscience Studies

subject:
Motor Control
Reflex
Feedback
Motor Cortex

abstract: Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2011-01-18 09:19:24.579

abstract:
A recent theory of motor control, based on optimal feedback control, posits that voluntary motor behaviour involves the sophisticated manipulation of sensory feedback. Although this theory can explain how people move in the world, it does not specifically describe how this control process is implemented by the nervous system. In this thesis, we propose and explore one physiological implication of this theory. Specifically, we hypothesize that rapid feedback responses should possess the key functional attributes of voluntary control because these two systems share a common neural pathway through motor areas of cerebral cortex.

Our first four studies were designed to elaborate the functional attributes of the long-latency stretch reflex, a fast feedback response which occurs 50-100ms following the mechanical stretch of a muscle. Consistent with our hypothesis, we found that the
long-latency response possesses many attributes commonly reserved for voluntary
control: the long-latency response is continuously modulated by subject intent (Chapter 2), it compensates for the size-recruitment principle of the motoneuron pool (Chapter 3) and it accounts for the mechanical properties of the upper-limb (Chapter 5). Further investigation revealed that the long-latency response can be decomposed into two functionally-independent processes (Chapter 4), and that one of these components contributes all of the sophistication observed in Chapters 2 and 3.

The goal of our fifth study was to investigate the neural basis of the long-latency response (Chapter 6). Our results provide strong evidence from both single-neuron recordings in non-human primates and transcranial magnetic stimulation in humans that primary motor cortex, which is known to be a critical node for voluntary control, also contributes to the sophistication of the long-latency response.

Taken together, the studies presented in this thesis demonstrate that the long-
latency response possesses several functional attributes typically reserved for voluntary control and that this sophistication likely arises via a transcortical pathway through primary motor cortex.

abstract: PhD


title: Sulfonamide Partitioning to Aqueous Cationic Micellar Systems

contributor:
Brown, R. Stephen
Buncel, Erwin
Chemistry

subject:
sulfonamide
binding constant
surfactant
partition coefficient

abstract: Thesis (Master, Chemistry) -- Queen's University, 2011-01-31 09:46:28.248

abstract:
Advances in analytical chemistry have resulted in a growing body of literature showing measurable concentrations of pharmaceuticals in both drinking and wastewater. Removal of such chemicals is typically inefficient and often poorly characterized. To characterize one such method of removal (micellar enhanced ultrafiltration, (MEUF)), interactions of a cetyl trimethylammonium bromide (CTABr) surfactant and sulfonamide antibiotics were examined by NMR and semi-equilibrium dialysis (SED).
The locus and orientation of binding in a micelle was established for seven sulfonamides by 1H NMR, and it was found that hydrophilic sulfonamides showed weak coordination with the micelle, whereas hydrophobic sulfonamides penetrated into the micellar interior with coordination of the SO2NH group to the charged surface layer.
Binding constants were determined by 1H NMR and showed apparent order of magnitude differences between nuclei. Several compounds were unable to be characterized in this manner due to low change in chemical shift with addition of CTABr. SED was performed as an alternative method to determine binding constants. Values determined in this manner were higher than those determined by 1H NMR. Binding constants were converted into changes in Gibbs free energy and used to evaluate and, where necessary, modify the orientation and locus proposed by 1H NMR.
Attempts are made to correlate binding constants with octanol-water partition coefficients to determine if a free energy relationship can be derived. Characterization of these systems may allow for a predictive methodology to determine the MEUF removal efficiencies of new sulfonamide and surfactant combinations. It is also hoped that this work may be generalized to predict MEUF efficiency for a wide range of contaminants that might be found in wastewater.

abstract: M.Sc.


title: The Relationship between In-School Physical Activity and Life Satisfaction, Self-Rated Health, Academic Performance, and Out-of-School Physical Activity: A Canadian Study

contributor:
O'Connor, Kathleen Steel
Johnson, Ana
Community Health and Epidemiology

subject:
Physical activity
School health
Health Promotion
Epidemiology
Life satisfaction
Self rated health
Academic performance
Out of school physical activity
Childhood health
Youth health
Childhood education
School education

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-01-21 10:42:29.807

abstract: The growing prevalence of childhood and adolescent physical inactivity and obesity are major concerns in Canada. Physical activity promoted within schools should be seen as a way to address these problems, since the majority of children receive public schooling. Research highlighting in-school physical activity helps influence school board and public health officials to create a physically active school environment. Consequently, this study has two objectives. The first is to describe the prevalence of in-school physical activity and four dependent variables in a nationwide sample of 9717 students, using data from the Health Behavior in School–aged Children survey. Dependent variables include life satisfaction, self-rated health, academic performance, and out-of-school physical activity. The second objective examines the association between in-school physical activity levels and these dependent variables, while controlling for potential confounders. Using existing data from the 2005/06 Health Behaviour in School-aged Children Survey, a partial proportional odds model form of ordinal logistic regression was fitted in order to investigate the relationship between in-school physical activity and self-rated health, life satisfaction, academic performance, and out-of-school physical activity, while controlling for potential confounders. The results showed a significant positive relationship between in-school physical activity and life satisfaction (OR range: 1.18 – 1.50), in-school physical activity and self-rated health (OR range: 1.10 – 2.86), in-school physical activity and academic performance (OR range: 1.20 – 1.40), and in-school physical activity and out-of-school physical activity (OR range: 1.09 - 6.68). Consequently, it is recommended that school environments which encourage physical activity continue to be promoted, and future studies continue to explore the benefits of in-school physical activity.

abstract: M.Sc.


title: Effects of Reinforcement and Soil Viscosity on the Behaviour of Embankments Over Soft Soil

contributor:
Rowe, Kerry
Civil Engineering

subject:
Reinforced Embankment
Finite Element Analysis
Geosynthetics
Elasto-Viscoplastic Soil Model

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2011-01-21 22:26:40.133

abstract:
A verified elasto-viscoplastic finite element model is used to develop a better understanding of the performance of embankments with geosynthetic reinforcement constructed over rate-sensitive soil. The interaction between reinforcement and prefabricated vertical drains (PVDs) and their effects on time-dependent behaviour of embankments are examined. For rate-sensitive soils, the generation of creep-induced pore pressures following the end of construction is evident along the potential slip surface. As a result, the minimum factor of safety with respect to embankment stability occurs after the end of construction. The combined use of reinforcement and PVDs are shown to provide an effective means of minimizing creep-induced excess pore pressure, increasing overall stability, and decreasing deformation of the embankments.
	The combined effects of the viscoelastic properties of geosynthetic reinforcement (polyester, polypropylene and polyethylene) and the rate-sensitive nature of foundation soils on the performance of embankments are examined. The effect of various factors, including reinforcement type (i.e., stiffness and viscosity), soil viscosity, construction rate and allowable long-term reinforcement strain, on the time-dependent behaviour of embankments are considered. The long-term performance of reinforced embankments is investigated for different maximum allowable long-term reinforcement strains. From a series of finite element analyses, the ideal allowable reinforcement strains to minimize embankment deformation while providing optimum long-term service height of the embankment, considering the effect of soil and reinforcement viscosity, are proposed for soils similar to those examined in this study.
	The currently proposed design methods for embankments with creep-susceptible reinforcement over rate-sensitive soils appear to be overly conservative. This study proposes a refined approach for establishing the allowable long-term reinforcement strains that are expected to provide adequate performance while reducing the level of conservativeness of reinforced embankment design.
	Finally, a previously developed elasto-viscoplastic constitutive model is modified to incorporate the effect of soil structure using a state-dependent fluidity parameter and damage law. The model was evaluated against data from a well-documented case study of a reinforced test embankment constructed on a sensitive Champlain clay deposit in Saint Alban, Quebec. The benefit of basal reinforcement and the effect of reinforcement viscosity are then discussed for these types of soil deposits.

abstract: PhD


title: West Coast Apocalyptic: A Site-Specific Approach to Genre

contributor:
Söderlind, Sylvia
English

subject:
Apocalypse
West Coast Literature
Cultural Geogrpahy
Genre Studies
Cultural Studies
Canadian Literature
American Literature
North American Literature

abstract: Thesis (Ph.D, English) -- Queen's University, 2011-01-26 14:00:17.35

abstract: Key studies of apocalypse in previous years have consciously and unconsciously understood the genre in terms of its paradigmatic consistency across examples. This emphasis points out valuable similarities among a wide range of texts, but also diminishes the significance of a text’s locally and historically rooted ways of depicting experience. This study reflects an effort to rebalance the meaning of apocalypse by looking at a specific locale – the North American West Coast. I examine popular, critical, and literary representations of the West Coast to trace out the unique ways that they configure regional identities. Ultimately, I make the case for site-specific criticism, which values provisional, locally rooted terminologies and tropes for analyzing cultural problems.

abstract: PhD


title: An Investigation of Leaching Chalcopyrite Ore

contributor:
Peacey, John
Mining Engineering

subject:
Chalcopyrite
Heap Leaching

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2011-02-15 15:59:38.15

abstract:
The abiotic leaching behavior of a chalcopyrite ore, from Asarco’s Ray-Mine, was conducted in shake flasks and miniature columns at elevated temperatures.  The shake flask tests, with an ore particle size of 1.18mm-2.38mm, found the highest Cu extraction was obtained using 1M NaCl in a 9.8g/L sulphuric acid solution at 60°C, with 69% Cu extracted in 16 days. The next highest extraction, 59% Cu extracted in 16 days, was achieved by adding fine pyrite at a 4:1wt ratio with the chalcopyrite content, in a 9.8g/L sulphuric acid solution at 60°C. Flask tests using other lixiviants and additions found copper extractions in the range of 30-40% Cu after 16 days. In the mini-column tests, the rates of copper extraction were similar for all test conditions. The rate of Cu extraction, even with a small particle size of 1.18mm-2.38mm and an elevated temperature of 50°C, was slow for all test conditions with an average rate of ~0.15% Cu per day.
The conceptual engineering of a hot, abiotic heap-leach for low-grade chalcopyrite ore, including hypothetical heat and mass balances was conducted.  The leaching time for a commercial operation was estimated from published data on laboratory column leaching of chalcopyrite ores and extrapolated to a commercial heap-leach by analogy with known leaching times for chalcocite ores. In commercial abiotic heap-leaches of chalcopyrite ore, the partial oxidation reactions generate insignificant heat to maintain an elevated heap temperature therefore the heat required to maintain the elevated temperature must be provided externally. In commercial biotic chalcopyrite heap-leaches, the in-situ total oxidation reaction generates more heat than the abiotic reactions but is still insufficient to rapidly raise and maintain an elevated heap temperature. For a low-grade Chalcopyrite heap-leach the most practical method of providing this heat is by injecting steam into the base of the heap using current air injection pipes. An external oxidant is required and for an abiotic heap-leach external ferric generation will be required.

abstract: M.A.Sc.


title: The Impact of Migration on the Evolution and Conservation of an Endemic North American Passerine:  Loggerhead Shrike (Lanius ludovicianus)

subject:
Migration
Birds
Laniidae
Stable Isotopes
Microsatellites
Moult
Deuterium
Morphology
Conservation Genetics
Population Genetic Structure
Banding
Migratory Connectivity

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2011-01-25 15:54:36.593

abstract: Migration acts as a selective force on the ecology and evolutionary trajectory of species, as well as presenting fundamental challenges for conservation.  My thesis examines the impact of migration by exploring patterns of differentiation among and within migratory and non-migratory populations of the Loggerhead Shrike (Lanius ludovicianus).  First, I use morphological, genotypic, stable isotope and leg band recovery data to quantify migratory connectivity in the species.  Comparison across markers reveals a generally concordant pattern of moderate connectivity to the Gulf Coast, but overall mixing among populations on the wintering grounds.  Combining data from multiple markers in a Bayesian framework improves the resolution of assignment of wintering birds to a breeding ground origin.  Information on the species’ migratory patterns provides an explicit framework for interpreting patterns of genetic and ecological variation.  I test two hypotheses regarding the interaction of gene flow and migratory habit:  (1) migration facilitates gene flow; and (2) gene flow will occur most often along the axis of migration.  Genetic population structure in migratory populations is weaker than in non-migratory populations, with gene flow facilitated by dispersal movements of females and first year breeders.  As predicted, gene flow occurs most often along the north-south axis of migration, likely due either to opportunistic settling of dispersers or potentially, pairing on the wintering grounds.  I investigate variation in the extent and scheduling of moult in relation to underlying genetic differences among populations, age, sex, body size, food availability and migratory habit.  I find a pattern of interrupted moult across migratory populations, which may represent a trade-off between time allocated to breeding versus molt and migration.  Loggerhead Shrikes in eastern and more southerly migratory populations undergo a greater extent of their moult on the breeding grounds and non-migratory individuals undergo a more extensive pre-formative moult than migratory individuals. I interpret this as suggesting a trade-off between resources allocated to molt versus those required for reproduction.

abstract: PhD


title: Engaging First Nations Youth through Reciprocal Intercommunity Exchange

contributor:
Lee, Elizabeth
Education

subject:
First Nations
Photo-Story
Education
Student Exchanges
Sharing Circles
Junior High School
Student Engagement
Ontario

abstract: Thesis (Master, Education) -- Queen's University, 2011-01-25 16:18:38.852

abstract:
This phenomenological study of a First Nations to First Nations reciprocal student
exchange elicited and explored the meanings of a reciprocal intercommunity exchange for grade
7 and 8 students in two First Nations schools. Representative student research participants from
one of the schools shared their pictures, stories and memories of their experiences through
photo-story (Truchon, 2007; Wang & Burris, 1997) and in a sharing circle (Lavallee, 2007).
The students‟ journeys were not only physical and geographical, but also emotional and
cultural. I also journeyed to an acceptance of my outsider/insider status growing up in a First
Nations community. As a non-Aboriginal researcher, I negotiated a space between the demands
of the academic institution and the First Nations community; and chose research methods that
were congruent with Indigenous Research Methodology (Wilson, 2008; Kovach, 2009; Smith,
1999).
The four themes that emerged from the data: community and relationships; culture and
ceremony; connections with place, and confidence building are congruent with AFN‟s vision of
“reciprocal inter-community exchanges promoting sharing of culture” (AFN, 2007) and with
Cajete‟s (1999) vision of “igniting the sparkle.” These students said that: “learning about
another culture made me want to learn more about my own.” Listening to these students share
what was gained through this exchange and their dreams for the future revealed their hope and
persistence. The example of a practice such as a reciprocal exchange which encouraged and
iii
engaged these youth could stimulate other First Nations communities to seek out similar
educational practices that would benefit their youth.

abstract: M.Ed.


title: Applications of Optimal Control Theory to Infectious Disease Modeling

contributor:
Day, Troy
Mathematics and Statistics

subject:
Infectious Disease Modeling
Optimal Control

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2011-01-25 19:59:17.263

abstract:
This thesis investigates the optimal use of intervention strategies to mitigate the spread of infectious diseases. Three main problems are addressed:
   (i) The optimal use vaccination and isolation resources under the assumption that these resources are limited. Specifically we address the problem of minimizing the outbreak size and we determine the optimal vaccination-only, isolation-only and mixed vaccination-isolation strategies.
  (ii) The optimal use of a single antiviral drug to minimize the total outbreak size,     under the assumption that treatment causes de novo resistance.
 (iii) The optimal use of two antiviral drugs to minimize the total infectious burden. Specifically we address the situation where there are two different strains and each strain is effectively treated by only one drug.

abstract: PhD


title: Using Adenosine Triphosphate (ATP) as a Substitute for Mechanical Stimulation for Tissue Engineering Applications

contributor:
Waldman, Stephen D.
Harrison, Mark
Mechanical and Materials Engineering

subject:
Cartilage
Tissue Engineering
Adenosine Triphosphate
ATP
mechanotransduction

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2011-01-28 10:49:47.118

abstract: Osteoarthritis is the end result of damage to articular cartilage, which lacks the ability to self-repair.  Tissue engineering of cartilage is a promising field of study that aims to promote healing of cartilage in vivo by manipulation of the chondrocytes that maintain the tissue, or through in vitro production of new cartilage for implantation into cartilage defects.  Tissue-engineered cartilage constructs require mechanical stimulation to produce matrix components in quantities and proportions similar to native cartilage tissue, and adenosine triphosphate (ATP) is thought to be an autocrine/paracrine biochemical mediator of these mechanical forces on the cell, after its release from chondrocytes under mechanical stress.  This study determined culture conditions for chondrocytes in 3D agarose scaffolds from mature donors undergoing total joint arthroplasty for the treatment of osteoarthritis, then supplemented these cells in vitro with exogenous ATP in concentrations varying from 50 nM to 1 mM in the presence of the radioisotopes [35S] and [3H]-proline, with radioisotope incorporation acting as markers of proteoglycan and collagen synthesis respectively.   The basal concentrations of ATP in the chondrocyte cultures as well as the ATP half-life in the cultures were determined by lucifer/luciferase assay and luminometry.  The P2Y receptor expression on the populations of chondrocytes from 8 donors was determined by flow cytometry, with largely varied individual expression and heterogeneity of P2Y1 and P2Y2 receptors.  Exogenous ATP was found to increase synthesis of matrix components by 200% of the control cultures at doses of 100 nM to 1 µM.  Patients with worse arthritis patterns, who were on chronic narcotic medications and who smoked were more likely to have a negative response to the exogenous ATP supplementation.  The basal concentration of ATP in the cultures was less than 1 nM, and the ATP half-life varied from 1-2 hours, depending on the expression of P2Y1 receptors expressed by the donor’s chondrocyte population (R2 = 0.99).  Supplementation of exogenous ATP to tissue-engineered cartilage in vitro appears to be a promising technique for improving the matrix synthesis of these constructs.

abstract: M.A.Sc.


title: Rotation Encoding of C-Arm Fluoroscopes With Accelerometer

contributor:
Fichtinger, Gabor
Electrical and Computer Engineering

subject: Fluoroscopy C-arm Tracking Encoding Accelerometer

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-01-28 12:07:32.781

abstract: Accurate, practical, and affordable pose tracking on manually operated C-arm fluoroscopes is a major technical challenge.  Conventional tracking methods, such as optical cameras and radiographic fiducials, are hampered by significant shortcomings.   Optical cameras are delicate, costly, and have a complex system setup that is easily susceptible to camera obstruction in cluttered operating room.  Radiographic fiducials occupy a significant portion of the fluoroscopic imaging space.  Using fiducials also requires segmentation that limits clinical use.   In this thesis, an alternative form of tracking is proposed to encode the rotational joints of manually operated C-arms using a tilt sensing accelerometer for tracking the C-arm rotational pose.  The technique is evaluated by affixing an accelerometer to a full-scale C-arm where a webcam is used as a substitute for X-ray imaging.  Ground truth C-arm rotational poses were obtained from the webcam by tracking a checkerboard plate.  From these rotational poses, a series of angle and structural correction equations were formulated that can properly relate the accelerometer angle readings to the C-arm rotational pose in real-time and compensate for systematic structural C-arm deformations, such as sagging and bending.  Real-time rotational pose tracking of the primary and secondary joint rotations of the C-arm showed an accuracy of 0.5 degrees in the entire range of interest.

abstract: M.A.Sc.


title: Elucidation of Protein‐Protein Interactions in the Flagella Structure and Characterization of the Glycosylation State of Flagellin Subunits of the Methanogenic Archaeon Methanococcus Maripaludis

contributor:
Jarrell, Ken F.
Microbiology and Immunology

subject:
Archaea
Flagella
N-Linked Glycosylation
Methanococcus Maripaludis

abstract: Thesis (Master, Microbiology & Immunology) -- Queen's University, 2011-01-28 11:50:05.542

abstract:
The archaeal flagellum is a rotating prokaryotic motility apparatus used for swimming motility and adhesion; however, it is more closely related to the bacterial type IV pilus system than its bacterial namesake. Methanococcus maripaludis is a highly flagellated, obligately anaerobic methanogen and is used as the archaeal model system during this study. The identified structural genes of the archaeal flagella are transcribed by a single fla operon; however, the interactions between the majority of the Fla proteins has yet to be elucidated. In this work, several
techniques were attempted to determine the protein-protein interactions between Fla proteins, including membrane fractionation experiments and in vitro dimerization assays. Evidence from these experiments suggests that two proteins, FlaC and FlaE, have the ability to self-associate. The M. maripaludis flagella system is also used as a model for the study of the N-linked
glycosylation pathway in the domain, due to the presence of a tetrasaccharide N-linked to flagellin monomers. Previous work has identified several of the processes involved in the assembly of this glycan, including glycosyltransferases, the oligosaccharide transferase and several of the key components involved in the biosynthesis of the sugar residue precursors. However, many of the enzymes responsible for biochemical modifications to the sugar residues remain to be determined. The operon structure of the genes between mmp1080 and mmp1095 was experimentally confirmed using RT-PCR, and each of the operons contains at least one gene involved in the biosynthesis of the N-linked glycan. In-frame deletions of genes in this region
were characterized for effects on the N-linked glycan. Evidence suggests that Mmp1082 and Mmp1083 are acting in conjunction with Mmp1081 in the addition of an acetamidino functional group to the third sugar residue. Mmp1085 was determined to be a methyltransferase responsiblefor the methylation of the terminal sugar residue. Additionally, Mmp1087 and Mmp1094 were identified as potentially having an effect on the glycan.
Though this work, the breadth of knowledge in regards to both the archaeal flagella and the N-linked glycosylation process in the domain has been increased.

abstract: M.Sc.


title: Basin Analysis and the Evaluation of Critical Factors for Unconformity-Related Uranium Mineralization, Paleoproterozoic Western Thelon and Otish Basins, Canada

subject:
Thelon Basin
Otish Basin
unconformity-related uranium deposits
basin analysis

abstract: Thesis (Ph.D, Geological Sciences & Geological Engineering) -- Queen's University, 2011-01-29 15:45:53.651

abstract:
Two Paleoproterozoic basins, the western Thelon Basin, and the Otish Basin, Canada, were investigated using basin analysis to evaluate critical factors for the formation of unconformity-related uranium deposits. The results serve to guide ongoing exploration at two under-studied uranium prospects in each basin, and help predict whether or not these basins have the potential to host high-grade uranium deposits in other locations.
	Sequence stratigraphy, in combination with mineral paragenesis indicates that unmetamorphosed basinal sandstones overlying the Boomerang Lake prospect, western Thelon Basin, were compacted and occluded by kaolinite and muscovite during diagenesis, and became diagenetic aquicludes that were unable to effectively conduct uranium-bearing basinal brines. Based on the high δ18O values of basinal and basement-influenced fluids, and the preservation of pre-Thelon-Basin 40Ar/39Ar dates of poorly-crystalline phyllosilicates in the basement rocks, hydrothermal alteration and uranium mineralization must have occurred at low water/rock ratios. This produced uneconomic amounts of U-bearing phosphate that was misidentified as uraninite in a previous report. A significant uranium deposit is unprobable based on the lack of unsupported radiogenic Pb near the prospect. However, intersections of thick, stratigraphically-higher diagenetic aquifers, which are marked by abundant dickite, and structurally-reactivated basement rocks on a different exploration trend remain the most prospective locations for a uranium deposit in the area.
	At the Camie River prospect, Otish Basin, diagenesis of basinal sediments in thick diagenetic aquifers was associated with fluids that were isotopically similar to seawater-derived basinal brines. The 1721 ±20 Ma Pb/Pb date obtained for Camie River uraninite coincides with intrusions of the Otish Gabbro, which triggered basinal fluid flow in diagenetic aquifers and uranium mineralization throughout the basin. The effects of late hydrothermal, metamorphic, and meteoric fluid events are restricted to fractures and faults. These zones also preferentially host radiogenic Pb and pathfinder elements that dispersed from the prospect, which can be utilized to vector towards additional deposits. The unconformity-type deposit model can be extended to basins as old as 2.0 Ga, as the Otish Basin demonstrates that atmospheric oxygen contents were high enough at this time to allow the evolution of U-leaching oxidizing basinal brines.

abstract: PhD


title: A Business Process Driven Approach for Automatic Generation of Business Applications

contributor:
Zou, Ying
Electrical and Computer Engineering

subject:
Business Process
Software Architecture Generation
User Interface Generation
Modifiability
Usability
Model Transformation

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2011-01-30 00:06:34.77

abstract:
Business processes describe a set of tasks for accomplishing business objectives of an organization. Business applications automate business processes to improve the productivity of business users. Nowadays, the business environment changes fast due to rapid market growth and technological innovations. Business processes are continuously updated to reflect new business initiatives. Business applications are frequently evolved to add features to meet new requirements and fix defects. Quite often, business processes and business applications evolve independently without direct reference to each other. Over time, it becomes more and more challenging to maintain the consistency between a business application and the corresponding business processes. Moreover, the existing development approaches rely on software developers’ craftsmanship to design and implement business applications. Such a development paradigm is inefficient and leads to inconsistency between business processes and business applications.
To facilitate the alignment between business applications and business processes, we present an approach that automatically generates software architecture and code skeletons of business applications from business processes. We identify architectural components from business processes by analyzing dependencies among tasks. To verify the achievement of quality requirements, we extend a set of existing product metrics to automatically evaluate the quality of the generated software architecture designs. Eventually, we apply refactoring strategies, such as software architectural styles or design patterns, to optimize the generated software architecture designs and resolve identified quality problems. Moreover, we also present an approach to automatically refine software architecture to design models and code skeletons of business applications. The effectiveness of our proposed approach is illustrated through case studies.

abstract: PhD


title: Understanding Identity Development and Adjustment of Young Adult Transracial Adoptees

contributor:
Freeman, John G.
Education

subject:
Transracial adoption
Identity
Adjustment
Education

abstract: Thesis (Master, Education) -- Queen's University, 2011-01-30 17:58:19.429

abstract:
The purpose of this qualitative study was to investigate the identity development and adjustment among young adult Transracial adoptees. To achieve this purpose, I conducted two separate interviews with four Transracially adopted adults (ages 19 to 28) and spoke about their perceptions and experiences regarding their respective identities, and their adjustments in interpersonal contexts such as education.
Although the participants have positive affect about their adoption placements, the participants continue to face challenges regarding their identities. However, as adults, the participants no longer dwell on such hurdles; they consider their identities to be continuously evolving, and their maturity has enabled their adjustment to be within their control. They suggest that a key aspect to this adjustment was their early knowledge of their adoption status. The participants also feel that educators should be aware of sensitivities with respect to Transracial adoption but not intervene specifically with Transracial adoptees except in the case of bullying. Future research should expand the current study by taking a more expansive view of the topic in respect to range of participants and data collection methods.

abstract: M.Ed.


title: The impact of a co-morbid mental disability on the experience of labour force disparities among Canadians with physical disabilities: an examination of the 2006 Participation and Activity Limitation Survey (PALS)

contributor:
Alvarado, Beatriz
Stuart, Heather
Community Health and Epidemiology

subject: Social epidemiology, Canadians with disabilities, labour force disparities

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-01-30 20:02:56.55

abstract:
Purpose: I examined two labour force disparities – unemployment and underemployment, among working-aged individuals (20-64 years) with self-reported disabilities using the 2006 Participation and Activity Limitation Survey (PALS). As disability type was the predictor of interest, two groups were compared: individuals with one or more physical disabilities (e.g. mobility, agility, pain) exclusively vs. those with one or more physical disabilities and a co-morbid mental disability (including depression, phobias or substance use).
Methods: This study was a secondary analysis of the 2006 PALS, a cross-sectional survey conducted by Statistics Canada to gather information about individuals whose everyday activities are limited due to a physical or mental condition that used the 2006 census as a sampling frame. I estimated the prevalence of unemployment (last week) and underemployment (last five years) and used multiple logistic regression to measure the association between disability type and each outcome, while considering other relevant covariates.
Results: Disability type was significantly associated with both unemployment and underemployment. Other significant effects were age, education level and family income quintile (in addition to current labour force status and frequency of health services access in underemployment), in both the bivariate and multivariate analyses. Those with a mental co-morbidity had approximately double the odds of being unemployed, relative to those with exclusively physical disabilities and the effect continued to be significant when disability severity was included in the model. Individuals with a mental co-morbidity also experienced greater odds (OR: 2.92) of reporting underemployment, compared to those with exclusively physical disabilities, though when disability severity was accounted for, the effect was reduced (OR: 1.52) and no longer significant.
Conclusion: To my knowledge, this is the first large-scale investigation using Canadian data to explore the association of disability type and two labour force disparities. In support of my hypothesis, individuals with a mental co-morbidity were found to be more disadvantaged in terms of both accessing employment and probability of encountering stigmatizing experiences in the workplace. More research is needed to gain a better understanding of the nature of these outcomes in order to progress toward the removal of significant barriers that persist in this population.

abstract: M.Sc.


title: Studying the Evolution of Build Systems

contributor:
Adams, Bram
Hassan, Ahmed E.
Computing

subject:
Software Evolution
Build Systems

abstract: Thesis (Master, Computing) -- Queen's University, 2011-01-31 12:46:06.082

abstract:
As a software project ages, its source code is improved by refining existing features, adding new ones, and fixing bugs. Software developers can attest that such changes often require accompanying changes to the infrastructure that converts source code into executable software packages, i.e., the build system. Intuition suggests that these build system changes slow down development progress by diverting developer focus away from making improvements to the source code.

While source code evolution and maintenance is studied extensively, there is little work that focuses on the build system. In this thesis, we empirically study the static and dynamic evolution of build system complexity in proprietary and open source projects. To help counter potential bias of the study, 13 projects with different sizes, domains, build technologies, and release strategies were selected for examination, including Eclipse, Linux, Mozilla, and JBoss.

We find that: (1) similar to Lehman's first law of software evolution, Java build system specifications tend to grow unless explicit effort is invested into restructuring them, (2) the build system accounts for up to 31\% of the code files in a project, and (3) up to 27\% of source code related development tasks require build maintenance. Project managers should include build maintenance effort of this magnitude in their project planning and budgeting estimations.

abstract: M.Sc.


title: Effects of Diabetes on Lymphocyte Phenotype and Function During Pregnancy

contributor:
Croy, B. Anne
Anatomy and Cell Biology

subject: Diabetes Immunology Lymphocytes Pregnancy

abstract: Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2011-01-30 23:46:23.151

abstract:
Diabetic pregnant women have an increased risk of developing pre-eclampsia, a late gestational syndrome, although the reason for this gain is unknown. Placental pathology in pre-eclampsia is linked with insufficient spiral arterial modification, a process triggered by uterine natural killer (uNK) cells, an abundant pro-angiogenic cell type found in early pregnancy decidua (endometrium of the pregnant uterus). UNK cells effect spiral arterial modification, the blood supply to the placenta, through the release of interferon gamma (Ifng), a pro-inflammatory cytokine. Peripheral blood precursors of uNK cells employ a unique pattern of homing molecules to traffic to the decidua. The goal of this thesis was to advance the understanding of how homing and functions of uNK cell precursors might be modified in diabetic pregnancy. Studies employed both murine and human models.
Pregnancies were studied microscopically in normoglycemic (n-) and hyperglycemic (d-) non-obese diabetic (NOD) and NOD.Ifng-/- (NOD strain with a genetic deletion of Ifng) mice. Pre-implantation embryo development was impaired in n- and d-NOD.Ifng-/- mice. Hyperglycemia decreased both numbers of uNK cells and spiral artery remodelling within d-NOD and d-NOD.Ifng-/- decidua. This decrease in spiral artery remodelling was independent of Ifng and linked with hypertrophy of smooth muscle in implantation sites.
Blood leukocytes from control and diabetic pregnant women were evaluated for adhesive function and expression of key homing molecules. Diabetic leukocytes had decreased CD56+ (uNK cell lineage) cell adhesion to decidua, increased CD56+ cell adhesion to pancreas, and comparable adhesion to lymph node compared with control leukocytes, suggesting impaired decidual homing in vivo. Of 8 lymphocyte subsets resolved by flow cytometry, type 1 cytokine CD56bright cells expressed appropriate homing molecules most abundantly. Diabetes did not alter levels of expression of these receptors.
These data show that diabetes alters the potential capacity for decidual homing of pre-uNK cells but that this is not achieved through reduction in levels of key homing molecules. Diabetes also reduced spiral arterial modification in mice through hypertrophy of smooth muscle. The reproductive challenges of diabetic women who have co-morbid immunological diseases merit further study.

abstract: M.Sc.


title: Development and Characterisation of Photocrosslinkable Poly(Ethylene Carbonate) Elastomers for Local Protein Delivery

contributor:
Amsden, Brian
Chemical Engineering

subject:
Polycarbonate
In Vivo Degradation
Oxidative Degradation
Surface Erosion
Biodegradable Elastomer
Photocrosslink
Angiogenic Growth Factor Delivery
Foreign Body Response
Therapeutic Angiogenesis

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2011-01-31 03:26:37.002

abstract:
Therapeutic angiogenesis is a promising application of local protein delivery.  Poly(ethylene carbonate) (PEC) is an interesting polymer due to its special degradation mechanism and good immunocompatibility and cytocompatibility.  Its biggest advantage over commonly used aliphatic polyesters is that it does not degrade to acidic products implicated in protein denaturation and tissue inflammation.  The degradation mechanism of linear PEC is thought to be oxidative, however the in vivo degradation rate is inappropriately rapid for angiogenic growth factor delivery.  To reduce the PEC degradation rate, low molecular weight PEC diacrylates were formed and then UV photocrosslinked to form elastomers.  The aims of this thesis were to evaluate the degradation and biocompatibility of these elastomers, and to determine formulation parameters that control the release of a model protein, bovine serum albumin, from porous elastomer matrices.

Diacrylated prepolymers were successfully prepared with molecular weights from 2,000 Da to 12,000 Da.  Elastomers were prepared from these prepolymers and characterised using NMR, DSC, ATR-FTIR, sol content and tensile testing. As hypothesized, crosslinking PEC slowed its degradation rate signifficantly compared to 60 kDa linear PEC (37 ± 4% mass loss in 12 weeks as compared to 78 ± 11% in 3 weeks). This result suggested that PEC degradation properties can be tuned for a range of tissue engineering or drug delivery applications.  For both linear and elastomeric PEC, a typical foreign body reaction was observed.  The degradation mechanism observed for the elastomer was the same as that for linear PEC and was consistent with the literature: cell-mediated surface erosion, which is demonstrated by linear mass loss, SEM observations, and pitted surface features.

The in vitro release of BSA-loaded porous formulations was rapid and/or incomplete.  The most promising formulation (12% BSA) produced a more prolonged release of two weeks than the other formulations tested, however the total fraction of BSA released was only 23%.  The formulation parameter that most significantly affected the release of BSA was the amount of DMSO used to vortex BSA particles.  These findings provide insight into the potential and limitations of PEC elastomers in protein delivery applications.

abstract: M.A.Sc.


title: Globular Cluster Kinematics and Dark Matter Content of the Isolated Elliptical NGC 720

subject:
Globular Cluster System
Kinematics and Dynamics
NGC 720

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2011-01-31 11:30:54.389

abstract:
We examine the globular cluster system (GCS) of the isolated elliptical NGC 720 using the Gemini Multi-Object Spectrograph (GMOS) and have obtained spectra for 241 candidate globular clusters (GCs) extending to a galactocentric radius of 40 kpc. Of the 241 candidates, 120 are confirmed GCs, where 46 are members of the metal-poor, blue, population and 74 are members of the metal-rich, red, population. A (g-i)=0.50 colour split is used to identify the blue and red populations. We measure the full GCS to have a rotational velocity (Vrot) of 50 +/- 7 km/s with a position angle (PA) of 170 +/- 69 degrees. The red population has a Vrot = 97 +/- 14 km/s with PA = 147 +\- 18 degrees and the blue population has a Vrot = 79 +/- 7 km/s with PA = 89 +/- 18 degrees. The full GCS has an average velocity dispersion of 168 +/- 22 km/s, for
the red population is 156 +/- 30 km/s and for the blue population is 181 +/- 33 km/s.
The velocity dispersion pro file for all populations is constant with increasing radius, suggesting the presence of a dark matter halo. Using a tracer mass estimator, we have measured the mass out to 40 kpc as 1.8(+0.6/-0.1)x10^12 Msun  for a potential which traces the dark matter pro file. We also estimate the M/L_V = 30 - 70. This study
extends our survey of GCSs to isolated environments.

abstract: M.Sc.


title: The Power of Ideas: The OECD and Labour Market Policy in Canada, Denmark and Sweden

contributor:
Banting, Keith G.
Political Studies

subject:
Public Policy
Policy Process
OECD
Ideas
Policy Transfer
Policy Diffusion
Denmark
Canada
Sweden
Policy Paradigm
Labour Market Policy
Policy Learning
OECD Jobs Strategy
Flexicurity
Comparative Public Policy

abstract: Thesis (Ph.D, Political Studies) -- Queen's University, 2011-01-31 12:49:18.185

abstract: This thesis advances our understanding of how ideas play a role in policy making by examining the processes and conditions that facilitate their international diffusion into domestic debates, their acceptance by policy actors, and the ways in which their acceptance alters policy processes and policy itself. Specifically, the thesis studies the impact of labour market policy ideas from the Organization for Economic Cooperation and Development (OECD) and its large-scale study on unemployment, the Jobs Study, in three OECD member states: Canada, Denmark and Sweden. This thesis shows that ideas play a number of roles: sometimes they are simply employed to help legitimize pre-determined policy positions; but sometimes a process of learning takes place, and new ideas change actors’ beliefs about what is and what ought to be, and as well their conception of their own interests and goals. Consistent with previous research, policy failure and uncertainty open actors up to the policy learning process and acceptance of new ideas. More than earlier studies, however, this thesis highlights the role of pre-existing beliefs. Accepting one new idea over another is largely determined by the values and beliefs actors bring to bear when judging new ideas; and thus, the cases show a pattern of acceptance for OECD ideas that largely follows along professional boundaries and/or ideological leanings. Moreover, pre-existing beliefs that are intertwined with an actor’s identity tend to be more resistant to change. As other ideational scholars argue, a change in individuals’ beliefs can alter both  the policy process and policy itself. When acceptance of an idea is widespread, problems of collective action can be overcome. When beliefs are not as widely shared, their impact on policy depends on many factors. Fragmentation of power and accountability can create “veto players,” and previous policies can create constituencies of supporters, some of whom may resist change. However, during a policy paradigm change, a shift in authority over policy can alter the political landscape and whose ideas matter. Given all these variables, the impact that a belief in new ideas can have on policy is highly mediated, and policy reforms, therefore, may not resemble the ideas which triggered the acceptance of change in the first place.

abstract: PhD


title: The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB

subject: GEANT4

subject: STF

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2011-02-01 10:31:34.688

abstract: SuperCDMS is the next generation of the Cryogenic Dark Matter Search experiment (CDMS), aimed at the detection of the Weakly Interacting dark matter Particles (WIMPs) with the use of phonon and ionization signals in germanium detectors operated at about 40 mK. The current experiment is operating in the Soudan underground laboratory in northern Minnesota. However, due to limitation of cosmic ray muons, in the next stage of SuperCDMS, the whole experiment will be moved to a deeper site at SNOLAB. This could reduce the influence of extraterrestrial high energy particles to a negligible level, leaving the natural radioactivity locally existing in the laboratory wall rock as the dominating background source. Along with this relocation, newly designed detectors will be implemented to further increase the sensitivity. The prototype of this kind of detector has been manufactured, but it needs to be carefully tested prior to its formal application. To thoroughly examine its performance, especially in an environment that is less affected by cosmic rays, a new detector testing facility is to be built underground at SNOLAB (STF) surrounded by a water tank serving as the passive shield against the natural radioactivity. A series of Monte Carlo simulations have been performed to investigate the effectiveness of the water tank shield, the background level and also the energy spectra of events in the detectors. The goal of 1 neutron/day and 1 Hz of gammas for external sources can be achieved.

abstract: M.Sc.


title: Geometric Aspects of Interconnection and Damping Assignment - Passivity-Based Control

contributor:
Guay, Martin
Chemical Engineering

subject:
Nonlinear Control
Nonlinear Systems
Geometric Control
IDA-PBC

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2011-01-31 12:59:56.828

abstract:
This dissertation deals with smooth feedback stabilization of control-affine systems via Interconnection and Damping Assignment - Passivity-Based Control (IDA-PBC). The IDA-PBC methodology is a feedback control design technique that aims to establish or manipulate a port-Hamiltonian structure of the closed-loop system.
For a mechanical control system, a port-Hamiltonian system is a natural description of the dynamics, and several effective controller designs have been presented for this class of systems. In other fields of engineering, the development of such controller design is an active area of research. In particular, applications of IDA-PBC techniques prove to be difficult in practice for process control applications where the concept of energy is usually ill-defined.
This thesis seeks to extend the application of the IDA-PBC methodology beyond mechanical control systems. This is achieved by following three directions of research.
First, we establish conditions under which a port-Hamiltonian system can be written as a feedback interconnection of two port-Hamiltonian system. We identify such an interconnection structure for linear control systems based on their intrinsic properties.
Second, as observed in application of IDA-PBC to non-mechanical systems, several additional assumptions on the structure of the desired port-Hamiltonian system can effectively reduce the complexity of the matching problem. We establish a unified approach that considers these additional assumptions. Third, we connect the matching problem to the classical feedback equivalence approach. We show that feedback equivalence between control-affine systems can be employed to construct some feasible interconnection and damping structures.

abstract: PhD


title: The Thrombogenic Influences of Factor VIII and von Willebrand Factor

contributor:
Lillicrap, David
Pathology and Molecular Medicine

subject:
Hemostasis
Thrombosis
Coagulation
Factor VIII
von Willebrand Factor

abstract: Thesis (Ph.D, Pathology & Molecular Medicine) -- Queen's University, 2011-01-31 13:50:07.481

abstract:
von Willebrand factor (VWF) and factor VIII (FVIII) circulate in the blood as a non-covalent complex.  VWF plays an important role in primary hemostasis through its interactions with components of the extracellular matrix and platelet glycoproteins, as well as through its stabilization of FVIII.  FVIII plays a crucial role in the intrinsic coagulation cascade and in the propagation of coagulation.  The significant role of these two proteins in hemostasis is established, whereas little is known about the thrombotic effect of quantitative and qualitative variability in these proteins, particularly in the development of arteriolar thrombosis.  Therefore, we established a ferric chloride induced arteriolar thrombosis injury model to evaluate the thrombotic effect associated with elevated FVIII levels and with gain of function mutations in VWF.
The thrombotic effect of acute and extended elevations of FVIII level were evaluated using complementary in vitro and in vivo assays of thrombogenicity.  Acute elevations in FVIII levels were associated with non-linear increase in thrombogenic potential as measured by our ferric chloride induced injury model.  In addition, the elevation of FVIII levels for an extended time period did not further enhance the thrombogenic potential associated with elevated FVIII levels.
Type 2B von Willebrand disease (2B VWD) is a bleeding disorder that arises as a result  of gain of function mutations, leading to the enhanced affinity of the mutant protein for platelet glycoprotein Ibα (GPIbα).  We created transient transgenic mouse models of 2B VWD and were able to reproduce the 2B VWD phenotype in mice.  The circulating 2B VWF did not act as a prothrombotic stimulus: there was little or no thrombus formation after vascular injury and a marked failure of platelet accumulation at the sites of endothelial damage.
Finally, modified transient transgenic models of type 2B VWD were created, in which the circulating VWF shows enhanced binding affinity for GPIbα and resistance to ADAMTS13 mediated proteolysis. This protein was hypothesized to act in as a prothrombotic stimulus, but instead it inhibited thrombogenicity; there was no vessel occlusion following vascular damage and platelet accumulation was similar to that seen in the injured arterioles of VWF-/- mice.

abstract: PhD


title: Automated discovery of performance regressions in enterprise applications

contributor:
Zou, Ying
Hassan, Ahmed E.
Electrical and Computer Engineering

subject:
performance regression
performance verification

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-01-31 15:53:02.732

abstract: Performance regression refers to the phenomena where the application performance degrades compared to prior releases. Performance regressions are unwanted side-effects caused by changes to application or its execution environment. Previous research shows that most problems experienced by customers in the field are related to application performance. To reduce the likelihood of performance regressions slipping into production, software vendors must verify the performance of an application before its release. The current practice of performance verification is carried out only at the implementation level through performance tests. In a performance test, service requests with intensity similar to the production environment are pushed to the applications under test; various performance counters (e.g., CPU utilization) are recorded. Analysis of the results of performance verification is both time-consuming and error-prone due to the large volume of collected data, the absence of formal objectives and the subjectivity of performance analysts. Furthermore, since performance verification is done just before release, evaluation of high impact design changes is delayed until the end of the development lifecycle. In this thesis, we seek to improve the effectiveness of performance verification. First, we propose an approach to construct layered simulation models to support performance verification at the design level. Performance analysts can leverage our layered simulation models to evaluate the impact of a proposed design change before any development effort is committed. Second, we present an automated approach to detect performance regressions from results of performance tests conducted on the implementation of an application. Our approach compares the results of new tests against counter correlations extracted from performance testing repositories. Finally, we refine our automated analysis approach with ensemble-learning algorithms to evaluate performance tests conducted in heterogeneous software and hardware environments.

abstract: M.A.Sc.


title: Modeling the Thermal Stability of in vitro Diagnostic Bioassays

contributor:
McLellan, P. James
McAuley, Kimberly B.
Chemical Engineering

subject:
Stability Model
Biosensor

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2011-02-02 00:09:23.758

abstract: The objective of this work is to develop mathematical models for predicting the thermal stability of commercial diagnostic assays. These assays are a product of the Point of Care division of Abbott laboratories, and are used for analyzing patient blood samples for specific substances. The accuracy of the results from these diagnostic tests relies on the activity of specific biological and/or chemical components of the sensors. Mathematical models that describe the stability of these active components are useful for supporting product shelf-life claims and for the design and implementation of accelerated testing protocols. In the thesis, the stability of two diagnostic assay systems of interest to Abbott Point of Care is investigated using mathematical modeling. For the first assay system investigated, the biosensor associated with the assay is identified as an important factor for product stability. A second-order dynamic model is developed to describe the thermal stability of this biosensor. The model corresponds to a reversible reaction followed by an irreversible reaction, with rate coefficients having Arrhenius temperature dependencies. The second-order dynamic model provides improved predictions relative to a first-order dynamic model, based on a comparison between model fits for two experimental datasets, and a comparison of predictive ability for a validation dataset. The second-order dynamic model is used to extend the concept of Mean Kinetic Temperature concept from the pharmaceutical industry to systems with higher-order dynamics. For the second assay system investigated, the calibration fluid is identified as a key factor in assay stability. A first-order model is developed to describe the stability of the analyte within the calibration fluid. The first-order model captures most of the trend present in the data from calibration fluid incubation experiments. Finally, model predictions are used to investigate the amount of change in assay response that can be attributed to changes in concentration of analyte in the calibration fluid (after storage at elevated temperatures). The results show that the changes observed in assay responses are consistent with the magnitude of changes in calibrant analyte concentrations predicted by the model.

abstract: M.A.Sc.


title: Comparison of  Pyramidal  and Magnocellular  Neuroendocrine Cell Volume Responses to Osmotic Stress and Stroke - Like Stress

contributor:
Andrew, David
Neuroscience Studies

subject:
Pyramidal Neurons
Magnocellular Neuroendocrine Cell
Osmotic Stress
Oxygen Glucose Deprivation
Paraventricular Nucleus
Supraoptic Nucleus

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2011-02-07 17:55:08.333

abstract:
Acute brain cell swelling (cytotoxic edema) can occur in the first minutes of stroke, presumably as a result of brain cells taking up water. In extreme hypo-osmotic situations such as excessive water-loading by patients, uptake by brain cells can expand the brain, causing seizures. But is ischemic brain cell swelling the same as hypo-osmotic swelling?
Water can passively diffuse across the plasma membrane. However the presence of water channels termed aquaporins (AQP) facilitates passive water diffusion by 10-100 times. Unlike astrocytes, there is no evidence of water channels on neuronal plasma membrane. However, there is still much debate about which cells (neurons or astrocytes) swell during over-hydration or during stroke and if neurons and astrocytes can volume-regulate during osmotic stress.
The purpose of this study was to examine and compare the volume responses of PyNs and magnocellular neuroendocrine cells (MNCs) to acute osmotic challenge and to OGD. We examined MNCs because they are intrinsically osmosensitive to small changes (2-3 mOsm) of plasma osmolality. We also examined if the same neurons behave similarly in brain slices or  when dissociated and if they respond differently to acute osmotic stress and stroke-like stress.
Our results indicate that during acute osmotic stress (±40 mOsm) half of dissociated PyNs and MNCs tended to show appropriate responses. MNCs  in brain   slices showed similar responses to when they  were dissociated, while brain slice PyNs were less responsive than when dissociated. Exposure to OGD resulted in obvious differences between the two types of in vitro preparations. Dissociated PyNs and MNCs showed no consistency in their volume responses to 10 minutes of OGD. Dissociated neurons swelled, shrunk or were unchanged in about equal numbers. In contrast, brain slice PyNs underwent profound swelling whereas, brain slice MNCs showed minor volume decreases.
We conclude that about half of our dissociated neurons were too variable and unpredictable in their osmotic volume responses to be useful for osmotic studies. They also were too resistant to stroke-like stress to be good models for ischemia. Brain slice neurons were similar in their osmotic responses to dissociated neurons but proved to have consistent and predictable responses to stroke-like stress.

abstract: M.Sc.


title: Evidence for Involvement of the Cysteinyl Leukotriene Type 2 Receptor (CysLT2R) in the Regulation of Food Intake and Body Weight and Possible Role for Vagal Afferents

contributor:
Beyak, Michael J.
Physiology

subject:
Vagus Nerve
CysLT2R
Food Intake
Satiety

abstract: Thesis (Master, Physiology) -- Queen's University, 2011-02-04 10:48:47.018

abstract:
The field of food intake and satiety has received increasing interest from the research community in recent years. The mechanisms and factors that regulate satiety gains their importance from the crucial role they play in food consumption and consequently control of body weight.
Leukotrienes are mediators that are released in inflammatory conditions. One of the receptors on which Leukotrienes perform their actions is Cysteinyl Leukotriene Receptor Type 2 (CysLT2Rs). Recently, our colleagues made the observation that CysLT2Rs are expressed in vagal afferent neurons. In addition, CysLT2R-/- mice appeared to be heavier than WT (Moos and Funk, unpublished observations). Based on these findings, I hypothesized that CysLT2Rs play a role in regulating food intake via vagal afferent activity. In-vivo studies were performed to characterize body weight gain and investigate whether weight gain was associated with increased food intake. I found that CysLT2R-/- mice not only have significantly higher body weight, but also eat significantly more than CysLT2R+/+ mice. Using calcium imaging techniques, I demonstrated that LTD4 and LTC4 increased calcium Ca2+ influx in nodose ganglion neuron. Moreover, the level of neuronal activation in the brainstem (NTS area) was measured in both groups of mice using immunohistochemical techniques, which suggested less postprandial neuronal activity in KO mice.
These data suggest that CysLT2Rs take part in regulating body weight and food intake. In addition these results implicate vagal afferents as a possible pathway.  These findings may have implications for the control of food intake in both health and disease and may lead to novel insights in the causes and treatment of disordered weight such as overweight and obesity, or even anorexia.

abstract: M.Sc.


title: Surface Electromyography of the Pelvic Floor Musculature: Reliability and Validity of a Novel Electrode Design

contributor:
McLean, Linda
Rehabilitation Science

subject:
electromyography
biofeedback
EMG
pelvic floor muscles
levator ani
crosstalk
motion artifact
reliability
novel electrode

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2011-02-07 14:46:30.811

abstract:
Purpose: Intravaginal probes used for recording electromyography (EMG) from the pelvic floor muscles (PFMs) likely record activity from nearby muscles (crosstalk), and move during functional tasks, causing motion artifact data contamination, threatening the validity of results obtained. This study investigated the test-retest reliability and validity of surface EMG recordings from the PFMs using a novel, theoretically superior electrode in comparison to a commercially available intravaginal probe, the FemiscanTM. Methods: Healthy subjects (n=20) performed tasks with each vaginal electrode in situ: i) PFM maximal voluntary contractions (MVC), ii) coughs, iii) unilateral hip adductor/external rotator contractions at 25%MVC, 50%MVC, and MVC while keeping the PFMs relaxed or maximally contracted, and iv) transversus abdominis contractions (TrA; recorded using fine-wires) at 25%MVC, 50%MVC, MVC.
Analyses: i) Intraclass correlation coefficients (ICC), ii) t-tests of proportions (α=0.05), iii) repeated measures ANOVAs and Tukey’s post-hoc testing (α=0.05) and iv) cross-correlation functions between peaks of transversus abdominis and PFM activity were used to determine the between-trial and between-day reliability of each vaginal electrode, a difference in prevalence of motion artifact contamination between electrodes, and the presence of crosstalk from the hip and TrA, respectively.
Results: Between-trial reliability of both vaginal electrodes was excellent (ICC(3,1)=0.943-0.974). Between-day reliability was less consistent (ICC(3,1)=0.788-0.924 and 0.648-0.715 for the FemiscanTM and novel electrode, respectively). No significant difference in the proportion of files contaminated with motion artifact using each electrode existed. At submaximal intensities of hip muscle contractions, the FemiscanTM recorded significantly higher EMG amplitudes compared to what it recorded when the hip was relaxed, whereas the novel electrode did not, indicating that the FemiscanTM recorded crosstalk from the hip musculature. Low cross-correlation coefficients (<0.90) and large time delays (≥ 0.5 milliseconds) between peaks of PFM and TrA activity indicated that neither vaginal electrode recorded crosstalk from the TrA.
Conclusion: The novel electrode is a promising tool to record EMG from the PFMs, as it records less crosstalk from the hip musculature than current technology while maintaining a high degree of reliability when comparing results collected within the same session; however, this electrode should not be used to compare one’s muscle activity between days.

abstract: M.Sc.


title: Comprehensive Study of the Electrochemical Formation of Thin Oxide Layers on Nickel and the Electrochemical Reduction of Monolayer Oxides on Platinum

contributor:
Jerkiewicz, Gregory
Chemistry

subject: Electrochemistry Nickel Platinum Oxidation Reduction Monolayer Mechanism

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2011-02-08 10:58:54.114

abstract:
The anodic polarization of Ni electrode in 0.5 M aqueous KOH solution at various polarization potential (Ep), time (tp) and temperature (T) values leads to the formation of β-Ni(OH)2 films. The growth of the hydroxide layers are irreversible and cannot be reduced electrochemically to metallic Ni. The hydroxide layer becomes thicker at higher values of Ep and/or tp and/or T. The thickness of β-Ni(OH)2 hydroxide were determined using ex–situ XPS and depth–profile techniques. Application of the oxide growth theories to our data indicate that the development of the β-Ni(OH)2 layer follows inverse logarithmic growth kinetics. The driving force of the process is the strong electric field that is established across the oxide layer. The strength of electric field is in the range of 0.015 – 0.197 x 109 V m–1.
The oxidation mechanism of the Ni(II) surface compound to Ni(III) is electrochemically irreversible and the process is treated according to Randles–Sevcik equation. A linear relation was determined between the peak current density (jp) and the square root of the potential scan rate (v1/2) for the entire range of Ep, tp and T. The diffusion coefficient (D) values calculated for anodic and cathodic processes are 8.1 ± 0.2 x 10–12 and 4.3 ± 0.2 x 10–12 cm2 s–1, respectively. The activation energy (Ea) values for the diffusion process are 23 ± 2 kJ mol–1 (anodic) and 26 ± 2 kJ mol–1 (cathodic). The D and Ea values calculated from chronoamperometry measurements are comparable with those calculated from jp vs. v1/2 plots.
The electro–reduction of PtO electrochemically pre–formed on Pt electrode in 0.5 M aqueous H2SO4 solution was also investigated. A well–controlled reduction conditions (Er, tr and T) were applied to determine the amount of the reduced PtO oxide. The reduction of the PtO requires much less time once ca. 1 monolayer (ML) of the oxide has been removed (ca. 1 ML of PtO remains). As expected, the longer tr and/or lower Er values, the greater the amount of the reduced oxide and consequently the smaller the amount of the remaining PtO oxide.

abstract: PhD