title: Social Capital and Mental Health: Public Perceptions of Mental Illness and the Accrual of Social Capital

contributor:
Sacco, Vincent F.
Sociology

subject:
Mental Health
Social Capital
Social Networks
Mental Illness

abstract: Thesis (Master, Sociology) -- Queen's University, 2013-11-22 00:31:17.297

abstract:
As much as the psychosocial nature of mental illness cannot be ignored, it is generally agreed that social ties play a beneficial role in the maintenance of psychological well-being. Small social networks, few close relationships, and low perceived adequacy of social support and quality of life have all been linked to depressive symptoms. Conversely, the challenges of establishing a causal relationship to social ties are generally greater for mental health than they are for other health outcomes.
The purpose of the present study was to identify the association between social capital and overall psychological well-being among Canadian citizens aged 12 and older, by conducting a secondary analysis of microdata using the 2009/2010 cross-sectional Canadian Community Health Survey.
The present study included a weighted sample of 124,188 individuals aged 12 years or older who participated in the Canadian Community Health Survey from 2009-2010. Ordinal regression was used to examine the association between self-perceived mental health and social capital in the context of community involvement and sense of belonging in the community.
Respondents who felt a sense of belonging in their local community reported mental health superior to individuals who did not have a community-based sense of belonging. This association was explained by respondent’s age, sex, marital status and was mediated by voluntary organization membership and immigration status.
Results provided evidence of a relationship between elements of social capital and mental health. Positive social relationships and civic engagement are relevant to positive mental health.

abstract: M.A.


title: Asthma Management Practices In Two Ontario School Districts: Applying Knowledge to Action

contributor:
Sears, Kim
Nursing

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:
School Setting
Asthma Management

abstract: Thesis (Master, Nursing) -- Queen's University, 2013-11-25 11:38:01.902

abstract:
Background:  School settings are one of the most crucial context for asthma management second only to a child’s home.  Today school administrators are faced with many challenges, not only are they responsible for students' learning needs but they also manage complex behavioural and health issues including asthma.  Most do not have standardized plans regarding asthma management.
Objectives:  1) Systematically review the research literature related to asthma management within the school setting.  2) Determine current asthma management practices as reported by school administrators.  3) Explore experiences and barriers to asthma management practices with school administrators.
Method:  Guided by the Knowledge to Action framework, the study was divided in three phases using a planned action approach and included an integrative synthesis of the evidence, an administrators’ survey, and an administrator’s meeting.
Findings:
Phase One:  Following a search using three databases, 67 articles were critiqued.  The literature illustrates that many countries have established “asthma friendly schools” legislation that includes process for identifying children with asthma, right to self-carry and administer medications, enhancing communication and cooperation between school staff, parents, and children with asthma, reducing triggers in school environment, and effective policies that make legislation a functioning reality within schools.
Phase Two:  Ninety-seven surveys were distributed within two district school boards with 61 completed surveys returned (63% response rate).  Key findings included underestimation of the prevalence of asthma, no standardized process for identifying children with asthma, staff training deficiency for recognizing and responding to asthma exacerbations, lack of individual asthma action plans for children, absence of programs to support current legislation and best practice guidelines.  Communication was the most common barrier identified by school administrators.
Phase Three:  Two principals in an administrator’s meeting validated the survey results.  Participants were not familiar with the concept of asthma friendly school, asthma prevalence rates, or free school asthma resources.  Asthma Action Plans were not universally understood as individualized written plans but rather a generalized first aide response plan.
Conclusion:  There are knowledge and practices gaps placing children with asthma at risk for exacerbation and death within school setting.  Administrators want to partner to facilitate optimal asthma management within the school setting.

abstract: MNSc.


title: Durability of HDPE Geomembranes for Municipal Solid Waste Landfill Applications

contributor:
Rowe, Kerry
Civil Engineering

subject:
Municipal Solid Waste Leachate
Antioxidants
GMB Thickness
Time to Nominal Failure
Geomembrane
Service-Life
Longevity Simulators
HDPE
Stress Cracking
Brittle Rupture
Durability
Landfill

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-11-26 12:36:01.538

abstract:
A series of laboratory accelerated immersion tests are used to examine the effects of different chemicals found in municipal solid waste leachate, geomembrane thickness, and incubation temperatures on the degradation of different high density polyethylene geomembranes. It was found that surfactant was the key leachate constituent affecting antioxidant depletion while salts accelerated degradation of the mechanical properties, especially stress crack resistance. Immersed in synthetic leachate, the time to nominal failure at 35oC was predicted to be 62% longer for the 2.5 mm, and 12% longer for the 2.0 mm, than for the 1.5 mm geomembrane tested. The antioxidant depletion in synthetic leachate and air at temperatures > 85oC was consistent with what would be expected from Arrhenius modeling based on data from lower temperatures (≤ 85oC). However, the early depletion rates in water incubation decreased with the increase of the temperature above 100oC. It was also found that at temperatures above 100oC, there was significant change in the polymer morphology that affected the stress crack resistance at early incubation times prior to polymer degradation.
Large-scale geosynthetic liner longevity simulators (GLLSs) which simulated field conditions were used to investigate the susceptibility of pre-aged high density polyethylene geomembranes to stress cracking and to evaluate the performance of geomembranes under a 150 mm sand protection layer. A pre-aged geomembrane with a 560 g/m2 geotextile protection layer experienced brittle rupture at local gravel indentations. The time to failure was correlated to the incubation temperatures. The use of a sand protection layer not only delayed antioxidant depletion compared to that with a traditional geotextile protection but also substantially reduced the long-term tensile strains in the geomembrane below the allowable strain limits.

abstract: PhD


title: An Electron Bombardment-Matrix Isolation Study of the Tropospheric Reactions of Toluene

contributor:
Parnis, Mark J.
Chemistry

subject:
electron bombardment matrix isolation
toluene
benzyl radical
troposphere

abstract: Thesis (Master, Chemistry) -- Queen's University, 2013-11-26 15:57:59.4

abstract:
The tropospheric reactions of toluene, acting as a model VOC, are investigated using an electron bombardment-matrix isolation system coupled with Fourier transform infrared spectroscopy.  Initial experiments to produce the hydroxyl radicals used to initiate the toluene reactions via electron bombardment of water-argon mixtures are performed. The effects of electron current, water concentration, and gas flow rate are investigated.
	A more efficient method of initiating the toluene reactions, by directly creating benzyl radicals through electron bombardment of toluene is then investigated, and the effects of toluene concentration and electron current on the production of the benzyl radicals is quantified.  Benzyl radicals are successfully produced, and identified via FT-IR.  The next step is the formation of benzylperoxy radicals, via electron bombardment of toluene-oxygen-argon gas mixtures.  Experiments are performed using increasing concentrations of toluene and oxygen, in an attempt to observe the benzylperoxy radical.  Two new absorptions are observed in the infrared spectra and are tentatively identified as due to the peroxy group on the benzylperoxy radical.
	Computational work is also performed to confirm that benzylperoxy radicals can in fact be produced from benzyl radicals and oxygen.  The vibrational frequencies of the benzylperoxy radical are also calculated, and used to confirm the possibility that the new absorptions seen in the infrared spectra could in fact be due to benzylperoxy radicals.
	The overall results from this work demonstrate that it is likely to be possible to use electron bombardment-matrix isolation systems to investigate tropospheric reactions of volatile organics, and that further experiments could be enhanced by structural modifications to the system.

abstract: M.Sc.


title: Does Religiosity Matter to Value Relevance? Evidence from U.S. Banking Firms

contributor:
Thornton, B. Daniel
Management

subject:
Fair Value
Value Relevance
Managerial Bias
Religiosity

abstract: Thesis (Ph.D, Management) -- Queen's University, 2013-11-28 11:01:35.578

abstract: I examine whether religiosity is positively associated with the valuation multiples investors assign to fair valued items that are prone to managerial bias. Using a sample of U.S. banking firms, I find that the value relevance of net assets that are hard to verify is higher for firms located in more religious areas than for those located in less religious areas. Moreover, I hypothesize and find that audit quality and firm information environment quality moderate the positive association between religiosity and value relevance. I perform several robustness checks. First, I rule out several alternative explanations to my results. Second, I address the concern that my results suffer from an omitted correlated variable problem. Third, I show that my results hold for firms located in Urban as well as Rural areas.

abstract: PhD


title: Behaviour of Deteriorated Pipes Rehabilitated With Grouted Slipliners

contributor:
Moore, Ian D.
Civil Engineering

subject:
Deteriorated Pipe
Polymer Liners
Slipliner
Surface Loads
Pipe Rehabilitation
Reinforced Concrete Pipe
Culvert Rehabilitation
Sliplining
Steel Pipe
Fibre Optic Strain Sensors
Distributed Strain Sensing
Rehabilitation

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-11-28 17:24:50.815

abstract: The goals of this research are to develop and validate the use of distributed fibre optic sensors for use in strain monitoring of buried culverts, and to use full-scale experiments to evaluate the performance of both deteriorated steel and reinforced concrete culverts rehabilitated with grouted slipliners subjected to surface loading. Bench scale experiments were conducted to evaluate the use of fibre optic sensors against conventional strain sensors.  Then, fibre optic sensors were attached to a full-scale culvert that was tested in a buried state as a proof of concept.  Finally, fibre optic sensors were used in two large scale buried pipe tests to explore the performance of rehabilitated flexible and rigid culverts.  A deteriorated steel culvert was tested in a buried state under surface loading, then rehabilitated with a grouted high density polyethylene (HDPE) slipliner while still in a buried state and tested under surface loading at 0.9 m and 0.6 m burial depths.  The rehabilitated steel pipe was tested under service loading, and up to 1250 kN of applied load.  The results suggested that the grouted annulus stiffened the overall structure, and increased the capacity of the system to over 3 times the fully factored design load. A deteriorated reinforced concrete culvert was tested and rehabilitated in a similar fashion. The grout in the annulus penetrated the cracks at the crown, invert and joint of the concrete pipeline. The lined concrete pipe was tested to 1200 kN under single axle loading, and to 800 kN under single wheel loading. The results suggested that while the concrete pipe was stiffened by the grout, it remained the primary contributor to structural capacity, with the liner contributing little to the capacity. Repair reduced the diameter change by an average of 90%, with the capacity reaching approximately 3.3 and 4.2 times the design loads for single axle and single wheel pair loading, respectively. The maximum response was under single axle loading over the barrels of the concrete pipe. In no instance did the structures reach an ultimate limit state, and the tests were stopped after bearing failure of the soil occurred.

abstract: Thesis is to be restricted to allow for the publication of journal papers prior to the release of this thesis document.

abstract: M.A.Sc.


title: Computer-Assisted Mosaic Arthroplasty: A Femur Model Trial

contributor:
Stewart, James
Kunz, Manuela
Computing

subject:
Computer Assisted Surgery
opto-electronic
patient-specific template
mosaic arthroplasty

abstract: Thesis (Master, Computing) -- Queen's University, 2013-11-28 17:06:06.961

abstract:
Computer assisted mosaic arthroplasty (CAMA) is a surgical technique that transplants cylindrical osteochondral grafts to repair damaged cartilage. An earlier in vivo study on sheep showed that short-term clinical outcomes are improved with the use of computer assistance, as compared to the conventional technique.

This thesis reports on a study comparing three mosaic arthroplasty techniques -- one conventional and two computer assisted -- on human anatomy. This in vitro study used solid foam femur models modified to incorporate simulated cartilage defects. There were five participating surgeons ranging from a third year resident to a senior orthopedic surgeon. Each of the five participating surgeons performed a total of nine trials. There were three distinct sets of identical solid foam femur models with simulated cartilage defects. Three surgical techniques (conventional, opto-electronic, and patient-specific template) were performed on each.

Several measures were made to compare surgical techniques: operative time; surface congruency; defect coverage; graft surface area either too high or too low; air volume below the grafts; and distance and angle of the grafts from the surgical plan. The patient-specific template and opto-electronic techniques resulted in improved surface congruency, defect surface coverage, graft surface within 0.50mm recessed and 0.25mm proud of the original surface, and
below-graft air gap volume in comparison to the conventional technique. However, the conventional technique had a shorter operative time. The patient-specific template technique had less variance in surface congruency and shorter operative time than did the opto-electronic technique.

abstract: M.Sc.


title: Phononic Crystal Waveguiding in GaAs

subject:
Phononic Crystal
Waveguide
Sagnac Interferometry
Surface Acoustic Wave

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-11-29 15:53:46.369

abstract:
Compared to the much more common photonic crystals that are used to manipulate light, phononic crystals (PnCs) with inclusions in a lattice can be used to manipulate sound. While trying to propagate in a periodically structured media, acoustic waves may experience geometries in which propagation forward is totally forbidden. Furthermore, defects in the periodicity can be used to confine acoustic waves to follow complicated routes on a wavelength scale. Using advanced fabrication methods, we aim to implement these structures to control surface acoustic wave (SAW) propagation on the piezoelectric surface and eventually interact SAWs with quantum structures.
To investigate the interaction of SAWs with periodic elastic structures, SAW interdigital transducers (IDTs) and PnC fabrication procedures were developed. GaAs is chosen as a piezoelectric substrate for SAWs propagation. Lift-off photolithography processes were used to fabricate IDTs with finger widths as low as 1.5 micron.
PnCs are periodic structures of shallow air holes created in GaAs substrate by means of a wet-etching process. The PnCs are square lattices with lattice constants of 8 and 4 micron. To predict the behavior of a SAW when interacting with the PnC structures, an FDTD simulator was used to calculate the band structures and SAW wave displacement on the crystal surface. The bandgap (BG) predicted for the 8 micron crystal ranges from 180 MHz to 220 MHz. Simulations show a shift in the BG position for 4 micron crystals ranging from 391 to 439 MHz.
Two main waveguide geometries were considered in this work: a simple line waveguide and a funneling entrance line waveguide. Simulations indicated an increase in acoustic power density for the funneling waveguides. Fabricated device evaluated with electrical measurements. In addition, a scanning Sagnac interferometer is used to map the energy density of the SAWs. The Sagnac interferometer is designed to measure the outward displacement of a surface due to the SAW. Interferometric measurements confirmed waveguiding in the modified funnel entrance waveguide embedded in the 4 micron PnC. However, they also revealed strong dissipation of the SAW in the waveguide due to the non-vertical sidewalls resulting from the wet-etch process.

abstract: M.Sc.


title: Salt-Doped Polymer Light-Emitting Devices

subject:
organic semiconductors
room temperature frozen junction

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-11-29 17:40:19.152

abstract: Polymer Light-Emitting Electrochemical Cells (PLECs) are solid state devices based on the in situ electrochemical doping of the luminescent polymer and the formation of a p-n junction where light is emitted upon the application of a bias current or voltage. PLECs answer the drawbacks of polymer light-emitting diodes as they do not require an ultra-thin active layer nor are they reliant on low work function cathode materials that are air unstable. However, because of the dynamic nature of the doping, they suffer from slow response times and poor stability over time. Frozen-junction PLECs offer a solution to these drawbacks, yet they are impractical due to their sub-ambient operation temperature requirement. Our work presented henceforth aims to achieve room temperature frozen-junction PLECS. In order to do that we removed the ion solvating/transporting polymer from the active layer, resulting in a luminescent polymer combined solely with a salt sandwiched between an ITO electrode and an aluminum electrode. The resulting device was not expected to operate like a PLEC due to the absence of an ion-solvating and ion-transporting medium. However, we discovered that the polymer/salt devices could be activated by applying a large voltage bias, resulting in much higher current and luminance. More important, the activated state is quasi static. Devices based on the well-known orange-emitting polymer MEH-PPV displayed a luminance storage half-life of 150 hours when activated by forward bias (ITO biased positively with respect to the aluminum) and 200 hours when activated by reverse bias. More remarkable yet, devices based on a green co-polymer displayed no notable decay in current density or luminance even after being stored for 1200 hours at room temperature! PL imaging under UV excitation demonstrates the presence of doping. These devices are described herein along with an explanation of their operating mechanisms.

abstract: M.Sc.


title: Social Capital, Social Inequality, and Democracy

contributor:
Sypnowich, Christine
Philosophy

subject:
Egalitarian
Ethics
Ethos
Exclusion
Inequality
Social Capital
Democracy

abstract: Thesis (Master, Philosophy) -- Queen's University, 2013-11-29 11:11:33.823

abstract: This thesis is a work of political philosophy. It aims to set out an egalitarian understanding of the promotion of social capital. The first chapter of the thesis is an introduction to social capital, and contains a normative criticism of contemporary social capital policy-making. A typology of theoretical approaches to social capital policies are outlined in the second chapter, including neoliberal constitutionalism, civic republicanism, and egalitarian pluralism. Of these approaches, egalitarian pluralism seems best able to promote social capital while balancing the competing values of freedom and equality. The third chapter builds on the egalitarian pluralist approach and investigates a relational egalitarian strategy for the promotion of social capital.

abstract: M.A.


title: Improvements on Single Point Incremental Forming Through Electrically Assisted Forming, Contact Area Prediction and Tool Development

contributor:
Jeswiet, Jack
Mechanical and Materials Engineering

subject:
Sheet Metal
Incremental Forming

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-11-29 16:06:51.964

abstract:
Single Point Incremental Forming (SPIF) is a die-less sheet metal forming method.
Because SPIF does not use custom tooling, this process allows for parts to be made
at low cost and short lead times. In this thesis electric current is applied through the tool to alter the formability of samples formed with SPIF. The research goal of this
work is to determine if formability is effected by resistive heating alone or if there is some formability change due to the current interacting with the material.
An apparatus that allows electrical current to be applied through the tool during
forming is designed and implemented. A method is also developed to allow the contact
area between the tool and sheet to be estimated, with particular focus on developing a method that allows for experimental measurement.
The effect of applied current on formability is estimated by evaluating the maximum wall angle that can be formed in a single pass, using a variety of tool sizes and current settings. Using the contact area model to estimate current density, a signicant increase in formability is found at a current density range that agrees with
previously published literature on electrically assisted forming of the same material.
The results show that across multiple tool sizes, a significant increase in formability is observed when applying a current density (A/mm2) larger than the current threshold
density published in the literature.
A study is also performed to test the performance of a set of novel tool shapes. By
using parabolic tools, it was found that formability can be improved while maintaining
low surface roughness.
Finally, a series of case studies are presented documenting the production several
parts for a variety of design groups and researchers at Queen's University. These case
studies provide examples for the uses of SPIF, as well as document the methods used
to produce these parts in greater detail than is present in the literature.

abstract: PhD


title: Population Control and Small Wars

contributor:
English, Allan
History

subject:
Population Control
Counterinsurgency
Guerrilla Warfare
Small Wars

abstract: Thesis (Ph.D, History) -- Queen's University, 2013-11-29 16:13:52.31

abstract:
This thesis argues that while there are various contending notions of how a government can improve its chances of success in a small war, few strategies will be effective without the application of a comprehensive program of population control measures. For this study, small wars are conflicts in which a government uses limited means to secure national objectives against an adversary who uses primarily the tactics of guerrilla warfare. Population control measures are defined as those restrictions imposed on movement, on choice of residence, and on the availability of food that protect the population from the insurgents while simultaneously denying the insurgents access to critical resources.
This work examines the vital importance of population control measures in overcoming guerrilla forces lacking external sponsors in small wars during the period 1870 to 1960.   Five examples are used to determine their importance: the treatment of prairie Amerindians in the Canadian West (1870 – 1890); the guerrilla phase of the Philippine-American War (1898 – 1902); the guerrilla phase of the South African War (1899 – 1902); the Malayan Emergency (1948 – 1960); and the Kenyan Emergency (1952 – 1960). Within the broad strategies used to prosecute these campaigns, population control measures were a consistent feature and were instrumental in contributing to the termination of the conflicts.  Despite their importance, these measures are typically overlooked or only treated superficially when discussed by historians. Therefore, to understand more fully the outcome of small wars, greater attention needs to be applied to the study of these measures.
In small wars the primary contest between the belligerents is for control of the people. For the government, the strategic value of population control measures is in how they separate the population from the guerrillas. This denies a wide range of critical resources to the guerrillas and additionally allows the government to both prosecute its campaign more effectively and protect the population better. Population control measures need to be a key component of a government’s strategy in a small war as their proper application may be the tipping-point between success and failure.

abstract: PhD


title: Cost-Effective Resource Configurations for Executing Data-Intensive Workloads in Public Clouds

contributor:
Martin, Patrick
Zulkernine, Farhana
Computing

subject:
Optimization
Data-Intensive Workloads
Resource Provisioning
tabu search
Cost Model
Performance Model
Inexpensive Deployment

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2013-11-30 19:30:39.427

abstract:
The rate of data growth in many domains is straining our ability to manage and analyze it. Consequently, we see the emergence of computing systems that attempt to efficiently process data-intensive applications or I/O bound applications with large data. Cloud computing offers “infinite” resources on demand, and on a pay-as-you-go basis. As a result, it has gained interest for large-scale data processing. Given this supposedly infinite resource set, we need a provisioning process to determine appropriate resources for data processing or workload execution. We observe that the prevalent data processing architectures do not usually employ provisioning techniques available in a public cloud, and existing provisioning techniques have largely ignored data-intensive applications in public clouds.
In this thesis, we take a step towards bridging the gap between existing data processing approaches and the provisioning techniques available in a public cloud, such that the monetary cost of executing data-intensive workloads is minimized. We formulate the problem of provisioning and include constructs to exploit a cloud’s elasticity to include any number of resources to host a multi-tenant database system prior to execution. The provisioning is modeled as a search problem, and we use standard search heuristics to solve it.
We propose a novel framework for resource provisioning in a cloud environment. Our framework allows pluggable cost and performance models. We instantiate the framework by developing various search algorithms, cost and performance models to support the search for an effective resource configuration.
We consider data-intensive workloads that consist of transactional, analytical or mixed workloads for evaluation, and access multiple database tenants. The workloads are based on standard TPC benchmarks. In addition, the user preferences on response time or throughput are expressed as constraints. Our propositions and their results are validated in a real public cloud, namely the Amazon cloud. The evaluation supports our claim that the framework is an effective tool for provisioning database workloads in a public cloud with minimal dollar cost.

abstract: PhD


title: Looking For and Mostly Finding the Literary In Contemporary American Nonfiction

contributor:
Wallace, Molly
English

subject:
literary nonfiction
American literature,

abstract: Thesis (Ph.D, English) -- Queen's University, 2013-11-30 22:27:36.61

abstract: Prose style criticism of literary nonfiction has faded from scholarly popularity since a boom in the 1980s. Recent literary criticism of nonfiction has focused on context while neglecting aesthetics, or left the work of style analysis to composition or rhetoric scholars. I examine the work of Joan Didion, David Foster Wallace, and two writers associated with the literary journal n+1, Keith Gessen and Elif Batuman, to demonstrate the way that prose style analysis is a meaningful critical approach that helps define changing nonfiction genres, including online genres. I read Didion's work across her oeuvre to demonstrate the way her prose style shifts subtly over time and between fiction and nonfiction, memoir and literary journalism. I trace the influence of David Foster Wallace's American postmodern forebears on his fictional and nonfictional prose styles, and follow that line of influence to the nonfiction writing of online genres. I conclude by discussing the way that young writers associated with the journal n+1 regard Wallace's influence on their work and the writing of their generation, and examine Gessen and Batuman's prose style on and offline to find the literary in some unlikely locations.

abstract: I prefer to restrict my dissertation for personal reasons.

abstract: PhD


title: Activation and Capture of Carbon Dioxide and Carbon Disulfide by N-Containing Compounds

contributor:
Jessop, Philip G.
Chemistry

subject:
nitrogen bases
activation
carbon disulfide
capture
carbon dioxide

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2013-12-01 19:16:55.257

abstract:
The interaction between carbon dioxide (CO2) and N-compounds such as 1,8-diazobicyclo[5.4.0]undec-7-ene (DBU) has been extensively studied in the Jessop Lab. Carbon disulfide (CS2) is the sulfur congener of CO2, although it exhibits different reactivity with N-containing compounds. This thesis presents the search for zwitterionic CO2-switchable polarity solvents, new and general reactivity of CS2 with amidines and guanidines, and attempts at using CO2 as a carbonyl source in the synthesis of nitrogen containing compounds.
In the second chapter, the reactions of CO2 with various diamines are described. Spectroscopic methods and X-ray crystallography determined the structure of a solid zwitterionic carbamate salt of CO2 and N,N’-dimethyl-1,3-propanediamine. The polarity of the liquid zwitterionic carbamate salt formed with N,N,N’-trimethyl-1,3-propanediamine was measured using UV-Vis and the solvatochromic dye Nile red; its polarity was comparable to previous switchable polarity systems. The CO2 gravimetric uptake of the liquid zwitterionic carbamate salt was 28%, far greater than other solvents for the capture and release of CO2.
In the third chapter, it was found that a variety of products can be accessed depending on the structure of the N-base (cyclic or acyclic) upon reaction of the base with CS2 at room temperature. The reaction of CS2 with cyclic amidines produced a cyclic trithioanhydride structure, forming a new C-C bond at a sp2-carbon beta to the imino nitrogen centre. When an amidine was acyclic it led to cleavage and formation of isothiocyanates in near quantitative yields. When a N-base had a N-H bond, CS2 can insert, forming a dimer in the presence of dichloromethane.
In the fourth chapter, preliminary investigations are ascribed for synthesis of α-amino acids, amides, and ureas. Carboxylation of ketimines was detected, although the formed carboxylates from a variety of ketimines readily decomposed. Isomerization products of two ketimines were generated with DBU and CO2. Lewis acid catalysts were implemented towards the amidation of benzoylacetic acid and synthesis of ureas. Amidation of benzoylacetic acid did not occur in the presence of Lewis acid catalysts and CO2. Formation of a cyclic tetraalkylurea was afforded in low yields by the use of a diamine, CO2 and Lewis acid catalysts.

abstract: PhD


title: The Pathogenesis of Vascular Calcification in Chronic Kidney Disease: Consequences and Treatments

contributor:
Adams, Michael A.
Holden, Rachel M.
Pharmacology and Toxicology

subject:
Vascular Calcification
Chronic Kidney Disease

abstract: Thesis (Ph.D, Pharmacology & Toxicology) -- Queen's University, 2013-12-01 15:12:54.388

abstract:
Vascular calcification (VC) is accelerated in patients with chronic kidney disease (CKD), resulting in increased risk of cardiovascular disease and mortality. Although the consequences of VC are associated with elevated pulse wave velocity (PWV) and left ventricular hypertrophy (LVH), the temporal impact on blood pressure changes is unknown. Mineral imbalance in CKD greatly contributes to the development of VC, and elevated serum phosphate is a major risk factor. Magnesium, which plays an important role in bone regulation, has been recently shown to be a modifier of VC, but whether magnesium inhibits calcification in CKD is unknown.
 A modified adenine model of CKD was developed in rats, characterized by mineral imbalance and progressive VC. During the development of VC, pulse pressure increased, which was driven by a drop in diastolic blood pressure, rather than systolic hypertension. Continuous pressure recordings in conscious rats using radiotelemetry revealed a significant increase in systolic variability associated with development of VC. Regional VC was associated with regional changes in the hemodynamic profile of the CKD rats. For example, only thoracic aortic calcification was associated with elevated PWV and pulse pressure. In contrast, the presence of abdominal and thoracic calcification differentially affected proximal and distal arterial pressure wave forms. CKD animals exhibited LVH, which was further increased by the presence of VC.  In addition, fibroblast growth factor 23, which regulates renal excretion of phosphate, was elevated in CKD animals at every time point and was associated with LVH independently from VC. Development of VC was characterized in an in vitro organ model. Phosphate elevation in vitro caused VC in aortas. In vitro, magnesium supplementation inhibited initiation and progression of VC. CKD animals given a magnesium diet also demonstrated attenuated development of VC. In patients with stage 3-5 CKD (excluding dialysis), dietary phosphate was associated with the progression of coronary artery calcification even after adjusting for use of phosphate binders, total dietary energy and total dietary protein.  Given the serious negative outcomes associated with development of VC, these findings fill key gaps in knowledge regarding the detection, management, prevention and treatment of VC in CKD.

abstract: PhD


title: Exciton relaxation dynamics in a one-dimensional semiconductor

subject:
carbon nanotube
one-dimensional semiconductor
exciton

abstract: Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-12-06 09:52:51.136

abstract:
Carbon nanotubes are intriguing materials and extensively studied for both their fundamental properties and extraordinary performance in various applications during the last 20 years. They are extremely small in diameter, light in weight, sensitive to the environment, strong, and chemically stable. They can be either metallic or semiconducting depending on their species.  The semiconducting species can absorb and emit light in a wide range of wavelengths. These outstanding properties of carbon nanotubes promise abundant applications that may be revolutionary.

The opto-electronic behaviour of a single-walled carbon nanotube (SWCNT) is extremely sensitive to its physical structure and ambient environment. Structural defects and surrounding environment are extrinsic influential factors that often obscure the understanding of the intrinsic behaviour.   Progress on SWCNT synthesis has been made continuously but not until the last 10 years, have single SWCNTs been isolated individually and from substrates so that their fluorescence can be detected.

The fundamental science of an optically generated exciton (an electron-hole pair) in an ideal semiconducting SWCNT is not fully understood despite many studies of exciton behaviour using various optical approaches. The major challenge is controlling SWCNT sample qualities.  SWCNT's fundamental properties, such as the absorption cross section, quantum efficiency, radiative and nonradiative lifetimes, remain under debate.  Knowing the intrinsic SWCNT properties is essential to understand exciton transport and relaxation mechanisms.

To minimize the extrinsic effects, we have selected high-quality unprocessed SWCNTs for investigation. Collaboration with Dr. P. Finnie and Dr. J. Lefebvre at National Research Council Canada, allow us to access pristine SWCNTs individually. Since the emission from a single SWCNT is low, it requires unconventional methods to measure the PL dynamics. Suggested by the results, exciton transport in a semiconducting SWCNT is diffusional at room temperature, with high diffusivity (130 -350 cm^2/s) and long diffusion length (1 - 5 µm). At lower temperatures, we observed a more efficient exciton-exciton interaction that suggests the contribution from hot excitons or a longer existence of delocalized excitons. Highly efficient exciton-exciton annihilation and  long coherence time in a SWCNT are promising for making a single-photon source at near-infrared wavelength range and developing quantum computers.

abstract: PhD


title: Centrifuge Modelling of Instability in Granular Soils under Infinite Slope Conditions

contributor:
Take, W. Andy
Civil Engineering

subject:
Instability
Physical Modelling
Slope Stability
Centrifuge
Geotechnical

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-12-03 21:06:56.806

abstract:
Rainfall induced granular flow slides pose a significant risk in many areas of the world.  These failures, characterized by the sudden release of material in a fluid-like manner, are the result of static liquefaction occurring in these slopes.  The static liquefaction phenomenon has been linked to instability.

Instability behaviour is primarily studied under undrained triaxial conditions, and although many instability theories have therefore been defined in this stress space, these have been shown to also extend into plane strain conditions.   In order to further investigate this behaviour under these stress conditions, Wolinsky et al. (2013) developed a tilt-table soil box for use in a geotechnical centrifuge to analyze instability in infinite slope soil models.  This testing apparatus has been used to simulate instability in plane strain under both dry and saturated soil conditions.

Stress-controlled experiments were performed on dry infinite slope soil models to investigate the effects of both void ratio and effective stress on instability behaviour.  By performing these tests dry, this test apparatus provides the ability to decouple the triggers of instability from the corresponding response in pore pressure and the consequences.  The results of this testing confirmed that the instability line angle is a function of both void ratio and effective stress.  As the void ratio decreases and effective stress in the soil model increases, the resulting instability line angle will increase.  This testing also demonstrated typical stress-dilatancy behaviour in these infinite slope models, characterized by contractive response in loose soils and dilative response in dense soil subject to increasing shear stress.

Secondly, this testing apparatus was used to investigate the effects of seepage force on instability behaviour in granular slopes through the introduction of groundwater seepage in the form of a rising groundwater level.  Although the results illustrated shear and volumetric response to these increased pore water pressures, these were not significant enough to initiate instability and the resulting pore water response leading to failure.  It has been determined that this apparatus must be further adapted to dissipate the matric suctions developed above the water table during groundwater rise.

abstract: Additional research on this project is yet to be submitted and defended

abstract: M.A.Sc.


title: Sensitivity Analysis of Models with Input Codependencies

contributor:
Harris, Thomas J.
Chemical Engineering

subject:
Global Sensitivity Analysis
Copulas
Dependent Random Variables

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2013-12-05 10:16:26.81

abstract: Assuming a set of variates are independent and normally distributed is commonplace in statistics.  In this thesis, we consider the consequences of these assumptions as they pertain to global sensitivity analysis.  We begin by illustrating how the notion of sensitivity becomes distorted in the presence of codependent model inputs.  This observation motivates us to develop a new methodology which accommodates for input codependencies. Our methodology can be summarized through three points:  First, a new form of sensitivity is presented which performs as well as the classical form but can be obtained at a fraction of the computational cost. Second, we define a measure which quantifies the extent of distortion caused by codependent inputs. The third point is regarding the modelling of said codependencies.  The multivariate normal distribution is a natural choice for modelling codependent inputs; however, our methodology uses a copula-based approach instead. Copulas are a contemporary strategy for constructing multivariate distributions whereby the marginal and joint behaviours are treated separately. As a result, a practitioner has more flexibility when modelling inputs.

abstract: M.A.Sc.


title: Becoming Superman: Interpolating Transsexuality into the Superman Narrative

contributor:
Tolmie, Jane
Gender Studies

subject:
sequential art studies
transsexuality
trans studies
comic studies
Superman
transgender
FTMs
superhero studies

abstract: Thesis (Master, Gender Studies) -- Queen's University, 2013-12-05 10:35:05.511

abstract: Reflecting the masculine ethos of the larger comic book industry, superhero comics continue to be male-dominated spaces.  Within comic studies, superhero scholars problematically normalize this androcentrism by reiterating the genre’s masculinist rhetoric, repeatedly positioning superheroes as stoic figures of whiteness, nationhood, heteronormativity and able-bodied masculinity.  Although some intervention has been made to challenge these interpretations, scholars fail to acknowledge how transgender and/or transsexual readers evaluate comic heroes.  This thesis provides one such intervention into the field, specifically focusing on the last son of Krypton, Superman.  Drawing together the work of trans, queer, feminist, psychoanalytic, and monster theorists, my research attempts to “trans” Superman; thus, (re)reading the Man of Steel in a way that distinctly reflects the experiences of those who are denied access to the figure via their/our own gender “transgressions”.  By interpolating transsexuality into the Superman narrative, I rewrite the figure’s place within the genre’s cis-sexist, masculinist history and while doing so, (re)position him as a more suitable hero for the trans community.

abstract: M.A.


title: Traversing Creative Space, Transforming Higher Education: A Contemporary Curricular Vision of Teaching and Learning

contributor:
Upitis, Rena
Education

subject:
transformative learning
adult education
graduate coursework
creativity

abstract: Thesis (Ph.D, Education) -- Queen's University, 2013-12-05 12:37:25.474

abstract:
The promotion of creative culture in the higher education classroom holds the potential to prepare students for their contemporary roles in an increasingly diverse and demanding modern world. A premise of this work is that education should strive to encourage creativity with process-oriented curricula that actively engage students in (a) tasks that are collaborative and novel, (b) the interpretation of new and meaningful experiences, and (c) the synthesis and critical evaluation of ideas at individual, collective, and global levels. This dissertation study identifies aspects of pedagogical design and teaching practice that enable the building of students’ creative capacities. These enhanced capacities, in turn, can lead to transformative experiences that inspire and shape participants’ personal and professional lives.
I adopted a dual role as researcher and student to conduct an exploratory study in the context of a PhD level Education course, Contemporary Curriculum Theory. Findings from this exploratory study informed a multiple-case study that involved the observation of two graduate level courses, Professionals in Rural Practice and The Lived Experience of Disability, which together form the unit of analysis for the study. Data sources included: (a) a Learning Activities Survey, modified from King’s (2009) original work; (b) a Creativity Checklist, modified from Munro’s (n.d.) instrument; (c) field observations and field notes; and (d) individual interviews with students and instructors from each course.
Data were analyzed by three creative drivers that enabled transformation: (a) multiple ways of knowing, (b) adult conversation, and (c) the storied self. Through this examination of university-level courses of varied disciplines, this research study addresses creativity as a catalyst for transforming the ways in which teachers and students experience knowledge-making in post-secondary education.

abstract: PhD


title: Comprehensive Characterization of Nickel-Based Metallic Foams and Their Applications as Electrocatalyst Materials

contributor:
Jerkiewicz, Gregory
Chemistry

subject:
Electrocatalysis
Electrochemistry
Nickel Foam

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2013-12-06 13:28:17.471

abstract:
This contribution explores the applicability of nickel-based metallic foams as active electrodes and as electrocatalyst support materials.  A comprehensive characterization of Ni and multi-component Ni-based foams is presented and includes the analysis of their structural, chemical, and electrochemical properties.  Several materials and surface science techniques as well as electrochemical methods are used to examine the structural characteristics, surface morphology, and surface-chemical composition of these materials.  X-ray photoelectron spectroscopy is employed to analyze the surface and near-surface chemical composition.  The specific and electrochemically active surface areas (As, Aecsa) are determined using cyclic voltammetry (CV).  The foams exhibit structural robustness typical of bulk materials and they have large As, in the 200 – 600 cm2 g–1 range.  In addition, they are dual-porosity materials and possess both macro and meso pores.
	Nickel foam electrodes are applied as electrocatalysts for the oxidation of isopropanol.  The process is studied under well-defined experimental conditions using cyclic voltammetry.  The outcome of these experiments demonstrates that isopropanol oxidation requires the presence of -NiOOH on the Ni foam electrode.  This surface oxide is generated at potentials near the potential of the isopropanol oxidation; however, the two processes do not occur exactly at the same potentials.  The Ni foam anodes sustain a current density of ca. 2.6 mA cm–2 throughout an electrolysis time of up to 600 minutes without significant loss of electrocatalytic activity.  Isopropanol is converted to acetone at a rate of ca. 5.6 mM per hour.
	The applicability of Ni foams as support materials for Pt is investigated.  Platinum particles are deposited on Ni foam in low loading amounts via the chemical reduction of Pt2+ and Pt4+ originating from aqueous Pt salt solutions.  The resulting Pt / Ni foams are characterized using electrochemical, analytical, and materials analysis techniques, including SEM to examine the morphology of the deposited material, CV to evaluate the Aecsa of the deposited Pt, and inductively coupled plasma optical emission spectrometry (ICP-OES) to determine the mass of deposited Pt.  The Pt / Ni foams are applied as electrocatalysts for hydrogen evolution, hydrogen reduction, oxygen evolution, and oxygen reduction reactions in alkaline electrolyte.

abstract: PhD


title: Imidazolium Ionomer Derivatives of Isobutylene-Rich Elastomers: Thermosets, Emulsions, Filler Composites and Clay Nanocomposites

contributor:
Parent, J. Scott
Whitney, Ralph A.
Chemical Engineering

subject: imidazolium elastomer thermoset composite emulsion ionomer isobutylene

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2013-12-11 15:34:32.691

abstract:
Ionomers are valued for their exceptional physical properties, antimicrobial activity and superior adhesion to high surface energy solids and polymer blend components. Carboxylate, or sulfonate derivatives, of ethylene-rich thermoplastics are the most commercially available ionomers. Elastomeric ionomers bearing quaternary ammonium and phosphonium halide functionality have a literary standing in both scientific and patent-based publications. Currently cationic ionomers have shown great prominence in their inactivity to a wide range of bacteria and fungi.
The specific focus of this research is in the derivatives of isobutylene-rich elastomers due to their exceptional impermeability, oxidative stability and vibration dampening characteristics. Imidazole-derived ionomers support a wider range of ionomer chemistry compared to ammonium and phosphonium analogues. N alkylation of nucleophiles including butyl imidazole, vinyl imidazole and 1,1’(1,4-butanediyl)bis(imidazole) by brominated poly(isobutylene-co-isoprene) yield thermally stable imidazolium bromide salts capable of supporting free radical cures and/or siliceous filler dispersions through further chemical modifications.
The versatility of imidazole chemistry extends to the synthesis of isobutylene rich thermoset ionomers. This derives material properties from both a network of covalent crosslinks and a network of ion pair aggregates. Un-crosslinked elastomers are prone to creep and stress relaxation, hence a need for thermoset ionomer chemistry. Ion pairs are poorly solvated by the low dielectric constant of the polymer backbone and favoured thermodynamically by way of self assembly of the ionic functionality. The aggregation of ion pairs establishes a non covalent network of polymer chains whose dynamic mechanical properties approach those of conventional covalent thermosets comprised of carbon-carbon and/or sulfide crosslinks. However, the lability of this ionic network leads to a poor response to static loads leaving the thermoformable ionomers unqualified for engineering applications. A direct route is a more desirable method in preparing thermoset ionomers comprised of covalent crosslink networks and ionic functionality.
In all, these reactive imidazolium ionomers look promising in supporting new value added applications for isobutylene rich derivatives, which include yet are not limited to elastomer thermosets, emulsions, filler composites and clay nanocomposites.

abstract: PhD


title: Small Molecule Inhibitors in EGFR/HER-2 and Mutant Ras/Raf Breast Cancer Model Systems

contributor:
Greer, Peter A.
Pathology and Molecular Medicine

subject: Abstract

abstract: Thesis (Ph.D, Pathology & Molecular Medicine) -- Queen's University, 2013-12-16 14:21:34.118

abstract: Dysregulation of receptor tyrosine kinase (RTK) signaling has been implicated in the pathogenesis of breast cancer. Both EGFR and HER-2 regulate tumor cell proliferation and survival through the Ras-Raf-Mek-Erk (MAPK) pathway. Cyclin-dependent kinases (CDKs) are implicated in regulating proliferative and survival signaling downstream of the MAPK pathway. Here I show that CDK inhibitors exhibit an order-of-magnitude greater cytotoxic potency than a suite of inhibitors targeting RTK and Ras-MAPK signaling in cell lines representative of clinically recognized breast cancer subtypes. Drug combination studies showed that the pan CDK inhibitor, Flavopiridol, synergistically potentiated cytotoxicity induced by the Raf inhibitor, Sorafenib.  In vivo mouse models of breast cancer treated with both drugs exhibited reduced primary tumor growth rates and metastatic tumor load in the lungs compared to treatment with either drug alone, and this correlated with greater reductions in Rb signaling and Mcl-1 expression in resected tumors. In addition, Mek inhibition with U0126 potentiated the cytotoxic efficacy of Sorafenib, showing added benefits of drug combination to reduce doses while achieving greater therapeutic efficacy in a mutant Ras/Raf triple-negative breast cancer cell line. In vivo mouse models showed targeted Raf (Sorafenib) and Mek (AZD6244) inhibition resulted in reduced primary tumor growth and metastatic tumor load in the lungs, with the combined targeted Raf and Mek treatment showing greater inhibition than targeting either Raf or Mek alone. Synergistic anti-tumorigenic effects of the Sorafenib-Flavopiridol and Sorafenib-U0126/AZD6244 combinations across breast cancer cells driven by EGFR/HER-2 or Ras-MAPK signaling suggest the broad applicability of these combinations to treat multiple breast cancer subtypes. These data highlight the significance of co-targeting Raf, Mek, and CDKs to effectively disrupt constitutive Ras-MAPK signaling that may give rise to resistance and metastasis.

abstract: Chapter 3 of my thesis is in preparation for submission for publication.

abstract: PhD


title: The Relationship Between Microstructure and Damage Evolution in Hot-Rolled Complex-Phase Steel Sheet

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

subject:
Complex-Phase
Steel
Damage Evolution

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-12-17 15:03:02.206

abstract:
Complex-phase (CP) steels are employed in applications that require high-strength and good edge formability. These steels derive their strength from a fine-grained bainite-ferrite microstructure, and alloying to provide solid-solution and precipitation strengthening. CP steels are produced industrially through a process of controlled rolling and cooling to produce desirable microstructures.
     Hole-expansion tests are typically used as a measure of edge formability for applications such as stretch-flanges. It has been shown that CP microstructures are susceptible to large fluctuations in hole-expansion performance with little change in processing or resulting tensile properties. The steel’s characteristics of damage evolution are critical to the hole-expansion performance.
     This study investigates the role of microstructure in the development of damage in CP microstructural variants. Two variant pairs of different thicknesses were produced from the leading and trailing edge of industrially produced hot-rolled sheet. Each pair consisted of a variant with poor hole-expansion performance, and a variant with good hole-expansion performance. Each variant was tested via interrupted double-notched uniaxial tension testing to induce damage. Damage evolution in each variant was quantified by X-ray micro-computed tomography (XµCT), and supplementary optical micrography. The damage results were correlated with microstructural characteristics.
     It was shown that poor hole-expansion variants failed by intergranular fracture. In these variants, void damage induced by hard martensite and retained austenite was not critical in producing failure. Purely void-damaged microstructures failed by ductile fracture, whereas cracked microstructures failed in a mixed brittle-ductile failure initiated by planar cracks. Microstructural banding of large elongated ferrite grains correlated with the existence of intergranular planar fractures.

abstract: M.A.Sc.


title: Investigation Into the Thermal Upgrading of Nickeliferous Laterite Ore

contributor:
Peacey, John
Mining Engineering

subject:
Thermal Upgrading
Selective Reduction
Limonite
Laterite

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2013-12-29 22:34:20.417

abstract:
Nickeliferous laterite ores are currently processed using complex energy intensive flowsheets. Limited mineral upgrading can be achieved by low-cost mineral processing as the nickel is not found as a separable mineral phase but finely disseminated throughout the host goethite mineral. Whole ore extraction processes are required which result in intrinsically higher capital and operating costs. Market pressure has provided incentives to develop alternative upgrading techniques that can produce a nickel concentrate and reduce the material input to downstream processing facilities.  Thermal upgrading through a selective reduction mechanism to produce a ferronickel concentrate has been studied extensively and has shown promising potential.  In this research, a two stage selective reduction of nickeliferous laterite ore was investigated at 600oC and 1000 – 1100oC with varying coal and sulphur additions.
Experiments showed that the limonite ore could be selectively reduced using a coal additive to a ferronickel and wustite phase. A combination of XRD and bromine/methanol diagnostic leach tests confirmed the presence of metallic nickel and iron in the calcine.  Higher degrees of metallization corresponded with higher sulphur additions and growth zone temperatures. Sulphur was added to improve particle growth through the establishment of a Fe-O-S liquid phase, which was found to improve Ni recovery from 13.8% to 75.8% over the range of 0 – 4 wt% S.
Ferronickel particles ranging in size from 20 – 60 microns were shown to be present but highly dispersed throughout the upgraded ore. Particle growth improved with higher growth zone temperatures and longer retention times. Magnetic separation of the calcine showed maximum upgrading of grades to 3 – 4 wt% nickel with recoveries ranging from 83.7 – 93.2%.  Partial oxidation of wustite particles to magnetite caused the particles to be magnetic and resulted in recovery of unwanted iron oxides. The presence of iron oxide fines was believed to allow for rapid oxidation of wustite phase and also produce slimes that hindered physical separation of the upgraded ore.

abstract: M.A.Sc.


title: The Lateral Septum and the Regulation of Anxiety

contributor:
Menard, Janet L.
Neuroscience Studies

subject:
fear
hippocampal theta
neuroscience
histamine
lateral septum
rat
defensive behavior
anxiety

abstract: Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2013-12-17 17:27:34.014

abstract: Compared to other structures, such as the amygdala, the lateral septum’s (LS) role in the regulation of anxiety and/or behavioural defense is relatively understudied. Thus, the overarching goal of this thesis was to further investigate its contribution to rats’ anxiety-related behaviours. In Chapter 2, we demonstrate, for the first time, that while the dorsal LS does not mediate rats’ appetitive motivation or anxiety in the novelty induced suppression of feeding (NISF) paradigm, it does modulate their defensive behaviours in the elevated plus maze (EPM) and shock probe burying tests (SPBT). In Chapter 3, we are the first to show that bilateral infusions of histamine, a neurochemical previously linked to anxiety, into the LS reduce rats’ anxiety-related behaviours in the EPM and NISF. In addition, we report a novel double dissociation between lateral septal H1 and H2, and H3 receptors in their regulation of rats’ defensive behaviours in those two paradigms. More specifically, the H1 and H2 receptors contribute to rats’ hyponeophagia in the NISF but not their open arm exploration in the EPM, while the H3 receptors modulate rats’ defensive behaviors in the EPM but not in the NISF. Finally, in Chapter 4, we report for the first time that infusions of histamine into the LS, which produce behavioural anxiolysis, increase rather than decrease the frequency of reticular-elicited hippocampal theta activity, a putative neurophysiological correlate of anxiolytic-drug action. Altogether, the data in this thesis increase our understanding of how the LS contributes to rats’ defensive behaviours and adds to the existing literature regarding the neurobiology of fear/anxiety. More importantly though, the data presented here could ultimately aid in the development of novel drugs to treat anxiety disorders in humans.

abstract: PhD


title: Elucidating the role of the Fes tyrosine kinase in breast cancer

subject:
Pathology
Breast cancer research

abstract: Thesis (Ph.D, Pathology & Molecular Medicine) -- Queen's University, 2013-12-18 11:44:40.294

abstract:
Fes was first discovered as a protein-tyrosine kinase-encoded by the v-fes retroviral oncogene. Retrovirally encoded Fes oncoproteins induced tumors in chickens and cats and cause tumors in transgenic mice; however, a role for Fes in human cancer has not been established. This thesis identifies tumor promoting roles of Fes through effects on stromal cells using genetic mouse models. First, in an orthotopic mouse mammary gland engraftment model, I found that loss of Fes in the host correlated with reductions in engrafted tumor growth rates, metastasis and circulating tumor cells, which may be partly due to reduced vascularity and fewer tumor-associated macrophages. We also showed Fes-deficient macrophages were less capable of promoting tumor cell invasion in co-culture experiments. Next, I observed delayed tumor onset in the absence of Fes in a transgenic mouse model of breast cancer driven by an activated HER2/Neu allele. This longer tumor latency correlated with hyperinflammatory status of Fes-deficient normal mammary glands. Taken together, these observations argue that Fes inhibition might provide therapeutic benefits in breast cancer, by attenuating tumor-associated angiogenesis and the metastasis-promoting functions of tumor-associated macrophages, or by delaying breast tumor onset in women with HER2 overexpression.
Finally, we showed that mice engrafted with IL-4 producing tumor cells developed tumors with significantly reduced growth rates and a complete attenuation of lung metastasis, which correlated with increased numbers of macrophages and enhanced phagocytic capability of macrophages in the tumor microenvironment. These observations suggest that IL-4 could be a good candidate for immunotherapy.

abstract: Two result chapters will be submitted as manuscripts to peer-reviewed journals.

abstract: PhD


title: Exploring the Role of Prosodic Awareness and Executive Functions in Word Reading and Reading Comprehension:  a Study of Cognitive Flexibility in Adult Readers

contributor:
Wade-Woolley, Lesly
Education

subject:
Executive Function
Cognition
Phonological Processing
Prosody
Adult Readers
Word Reading
Reading Achievement
Reading Comprehension

abstract: Thesis (Master, Education) -- Queen's University, 2013-12-19 16:15:50.64

abstract:
The current study examined the phonological process of prosodic ability in a model of adult word reading and reading comprehension ability. All phonological tasks involve executive functions (EF) reflected in an individual’s flexibility for manipulating different components of language. To account for the EF demands involved in phonological tasks of reading, EF was assessed using measures of inhibitory control and switching attention as both a control variable and predictor in each model of reading. Two research questions guided the study: 1) Do prosodic ability and EF make independent contributions to word reading, and reading comprehension ability when controlling for the other? 2) Do prosodic ability and EF make unique contributions to word reading, and reading comprehension ability when controlling for the other, in addition to controlling for vocabulary, fluid (nonverbal) intelligence, rapid automatized naming (RAN - Digits), and phonological short-term memory (PSTM)?
Participants were one hundred and three native-English speaking adults (18 to 55 years of age) recruited from Eastern Ontario. A total of 8 regression models were tested. The analyses revealed unique contributions of prosodic ability in adult word reading achievement, and EF in silent reading comprehension. Prosody’s contribution to word reading above EF supports prosodic awareness as a phonological skill that can be used to explain individual differences in word reading, whereas EF’s contribution to reading comprehension supports its’ role in more complex reading tasks. Prosody and EF represent constructs that warrant future consideration in models of reading.

abstract: M.Ed.


title: Contextual Influences on Family Role Transitions in Sub-Saharan Africa: The Case of Ghana

contributor:
Kay, Fiona
Sociology

subject:
Demography
Sub-Saharan Africa
Adult transition
Event history models
Ghana
Family formation

abstract: Thesis (Ph.D, Sociology) -- Queen's University, 2013-12-19 15:00:23.689

abstract:
This dissertation explores the cultural and socioeconomic factors that influence adult role transitions in Ghana. Guided by a life course theoretical framework, and using a nationally representative survey (2003-2008 Ghana Demographic and Health Surveys), I estimate accelerated failure-time (AFT) log-normal models that control for the potential effects of unobserved heterogeneity due to the possible omission of certain relevant covariates. The models reveal that when the most optimal hazard distribution function is specified in an event history model, the problem of unobserved heterogeneity becomes significantly reduced. Results from both non-parametric and parametric models suggest a convergence in marriage and parenthood timing among contemporary young women and young men in Ghana compared with their older cohort, highlighting the salience of sociocultural timing on individuals’ life course decisions.
The study also utilizes qualitative data from 30 in-depth interviews conducted in Aburi in the Eastern Region of Ghana, during the summer of 2010. The qualitative approach complements the survey methods by uncovering the influential role of the religious institution, a growing sense of individualism, as well as an emerging consumerist culture on family formation decisions in Ghana. Overall, the findings from this study indicate that the spread of information technology in the rapidly globalizing world has had differential effects on two birth cohorts in Ghana.

abstract: I intend to convert this work in the form of publishable journal articles in the next couple of years.

abstract: PhD


title: Characterization of Bioactive Components in Decellularized Adipose Tissue Scaffolds for Tissue Engineering

contributor:
Flynn, Lauren E.
Chemical Engineering

subject:
Tissue Engineering
Biomedical Engineering

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2013-12-19 16:22:32.717

abstract: In previous in vitro and in vivo studies, decellularized adipose tissue (DAT) has demonstrated unique bioactivity, but little is known about the bioactive components preserved in the decellularized scaffold. With the goal of characterizing the bioactive components in the DAT, protein was extracted from DAT samples from 3 donors using 5 different buffers.  The resulting DAT extracts were found to have very low protein content so molecular weight fractioning centrifugation was used to concentrate the samples. Concentrated extracts were screened for the presence of the bioactive components adiponectin, vascular endothelial growth factor A (VEGF-A), bone morphogenetic protein 2 (BMP-2) and Dickkopf related protein 1 (DKK-1) using Western blotting. Positive signal for BMP-2 was found for one donor in Roger’s Sample Buffer and Urea Buffer, but all other proteins investigated with Western blotting went undetected for all extraction buffers. Immunohistochemistry (IHC) was also used to determine the presence and distribution of bioactive components in the DAT samples. Sections of DAT were probed for the same bioactive components; adiponectin, VEGF-A, BMP-2 and DKK-1, with positive signals detected for adiponectin and VEGF-A. In order to develop an injectable, DAT-derived hydrogel for soft tissue regeneration, DATgels were fabricated from an enzymatically treated and homogenized DAT pre-gel suspension, which was neutralized to physiological pH and salt concentration. The highly-hydrated DATgels, containing up to 97% water, were found to degrade substantially over 14 days in simulated physiological fluid, with only a slight reduction in the overall scaffold size. Histology and SEM showed no major structural differences between the two formulations evaluated (40 mg/mL and 50 mg/mL), with both containing intact DAT features and small void spaces scattered heterogeneously throughout the scaffold. Preliminary in vitro cell work with adipose-derived stem cells (ASCs) showed that the 40 mg/mL formulation DATgel supported cell attachment and viability greater than 70% for all scaffolds up to 7 days after seeding. Further, migration into the scaffold was observed over time, indicating that the adhesive properties of the native ECM were retained through the processing steps required to fabricate the DATgels.

abstract: novel work completed in this thesis is to be published before public is given access.

abstract: M.A.Sc.


title: Parameter Estimation Techniques for Nonlinear Dynamic Models with Limited Data, Process Disturbances and Modeling Errors

contributor:
McAuley, Kimberly B.
Chemical Engineering

subject:
Maximum Likelihood
Parameter Estimation
Expectation Maximization
Chemical Engineering
Modeling Error
Stochastic  Disturbances

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2013-12-23 15:12:35.738

abstract: In this thesis appropriate statistical methods to overcome two types of problems that occur during parameter estimation in chemical engineering systems are studied. The first problem is having too many parameters to estimate from limited available data, assuming that the model structure is correct, while the second problem involves estimating unmeasured disturbances, assuming that enough data are available for parameter estimation. In the first part of this thesis, a model is developed to predict rates of undesirable reactions during the finishing stage of nylon 66 production. This model has too many parameters to estimate (56 unknown parameters) and not having enough data to reliably estimating all of the parameters. Statistical techniques are used to determine that 43 of 56 parameters should be estimated. The proposed model matches the data well. In the second part of this thesis, techniques are proposed for estimating parameters in Stochastic Differential Equations (SDEs). SDEs are fundamental dynamic models that take into account process disturbances and model mismatch. Three new approximate maximum likelihood methods are developed for estimating parameters in SDE models. First, an Approximate Expectation Maximization (AEM) algorithm is developed for estimating model parameters and process disturbance intensities when measurement noise variance is known. Then, a Fully-Laplace Approximation Expectation Maximization (FLAEM) algorithm is proposed for simultaneous estimation of model parameters, process disturbance intensities and measurement noise variances in nonlinear SDEs. Finally, a Laplace Approximation Maximum Likelihood Estimation (LAMLE) algorithm is developed for estimating measurement noise variances along with model parameters and disturbance intensities in nonlinear SDEs. The effectiveness of the proposed algorithms is compared with a maximum-likelihood based method. For the CSTR examples studied, the proposed algorithms provide more accurate estimates for the parameters. Additionally, it is shown that the performance of LAMLE is superior to the performance of FLAEM. SDE models and associated parameter estimates obtained using the proposed techniques will help engineers who implement on-line state estimation and process monitoring schemes.

abstract: PhD


title: Experimental and CFD Study of Effusion Cooling in an S-Bend Diffusing Passage

contributor:
Birk, Michael A.
Mechanical and Materials Engineering

subject:
S-Bend
CFD
Effusion Cooling

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-12-23 14:20:32.38

abstract:
This thesis presents an experimental and computational fluid dynamics (CFD) study on a rectangular S-bend with straight and diffusing passages with passive effusion cooling.  Experimental tests were performed at both cold and hot flow conditions over a range of Reynolds numbers from 2.5e5 to 4.5e5.  Hot flow testing was conducted with the primary flow temperature up to 300 °C.
Severe backpressure penalties occurred with full-surface passive effusion injection in cold flow tests.  Moderate penalties occurred with reduced surface coverage whereby the performance was affected by the S-bend secondary fields with injection at different locations.  High surface cooling effectiveness with full-coverage of cooling film was measured; the impacts from the S-bend secondary flow fields were measured to be minimal.
The CFD study revealed the importance of using experimental flow boundary conditions for simulations.  Using the standard k-ε model with wall functions was confirmed as appropriate for simulating the S-bend flow with effusion cooling.
A coarse-grid CFD methodology using a porous wall boundary condition to simulate the effects of effusion cooling was investigated.  From a design perspective, this model is preferable for quantifying the injection flow rate since the actual mass flow rate is not known.  Comparison to the alternative solution using uniform mass flow boundary conditions showed that both models incorrectly predicted the momentum.  The porous wall model, however, is promising for practical design applications of S-duct flow fields with effusion injections.

abstract: PhD


title: Adsorption of Polyamine Chelated Copper Ions Onto Gangue Minerals and High Capacity Adsorbents

contributor:
Kelebek, Sadan
Mining Engineering

subject:
Adsorption
Mineral Processing
Tailings
Copper
Mining
Flotation
Chelate
Polyamine

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2013-12-25 15:00:39.553

abstract:
The effluent quality from mining & processing operations is monitored to ensure that maximum allowable limits are not exceeded. Recently, copper concentration levels in the effluent discharge flows of a copper and nickel mining company in Ontario have indicated increasing trends. A chemical particular to the problem is use of diethylenetriamine (DETA) in the process.
Adsorption tests were conducted to investigate the ability of various adsorbents to remove and retain copper complexed with DETA and triethylenetetramine (TETA) in solutions. The tests were divided into two sections: gangue adsorbents (silica and pyrrhotite) and high capacity adsorbents (natural bentonite, peat, zeolite Y and zeolite ZSM-5).
Pyrrhotite as a sulphide gangue had a greater adsorption capacity than silica for the concentration range studied. At 1 ppm initial concentration, over 80% of copper chelate was removed by minus 400 mesh pyrrhotite compared to 72% of the same size silica. Freundlich and Langmuir isotherm models of adsorption are applicable. However, the Langmuir adsorption isotherm was found to more closely represent the experimental data with a maximum adsorption capacity of 129.9 μg/g for copper complexed with DETA on pyrrhotite.
For the high capacity adsorbents, natural bentonite, zeolite Y and peat each worked well at removing the copper chelates. Zeolite Y had the highest capacity for copper chelates and a maximum adsorption capacity of 55.9 mg/g. Freundlich and Langmuir adsorption isotherm models were studied with the Langmuir isotherm model more closely representing the experimental data.
iii
Studies were also conducted on the effect of temperature. This led to a thermodynamic analysis of adsorption and estimation of activation energies. The standard free energies estimated for adsorption of copper chelated on adsorbents studied were nearly always negative, typically varying from around -2 kJ/mol to -7 kJ/mol with increasing temperature. The activation energy was found to be highest for the natural bentonite system suggesting a strong adsorption (e.g. 40.5 kJ/mol for CuTETA). Desorption experiments on the peat indicated very poor reversal for the process, confirming that the adsorption of copper chelates on high capacity adsorption was indeed very strong. Settling experiments indicated copper chelates were highly effective as coagulants on bentonite.

abstract: M.A.Sc.


title: Towards Hydrogen Storing Systems for Vehicular Applications

contributor:
Jessop, Philip G.
Chemistry

subject:
Heterogeneous Catalysis
Hydrogen Storage

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2013-12-24 01:01:16.857

abstract: The rising environmental and financial consequences of using fossil fuels as an energy source and energy carrier are a global concern. Described herein are two hydrogen-storing technologies, each of which was envisioned as a potential solution to said consequences: hydrogen-storing polymethylpyridylsiloxanes for use as an alternative energy carrier to fossil fuels; and thermally regenerative fuel cell systems to supplement or supplant vehicular alternators. A thermally regenerative fuel cell (TRFC) system is being developed to convert waste heat from an internal combustion engine (ICE) system into electricity that can be used to power auxiliary vehicular components. The TRFC system will comprise a dehydrogenation reactor and a fuel cell positioned relative to the ICE system such that the two components are held at 200 °C and 100 °C, respectively. 1-Phenyl-1-propanol has been identified as an optimal hydrogen storing liquid (XH2) that will selectively dehydrogenate over a heterogeneous catalyst to give a dehydrogenated liquid (propiophenone, X) and H2. The heterogeneous catalyst that currently provides the best selectivity (99.65%) for X at 200 °C is Pd/SiO2. A selectivity of ≥ 99.9% was desired to obtain the longest possible operational lifetime for the working fluids XH2/X. To increase the selectivity for X from 99.65% to ≥ 99.9%, size and shape specific Pd nanoparticles were synthesized. Pd nanocubes (20 nm) provided the best selectivity for X at 99.26%. It was concluded that a reproducible selectivity for X of ≥ 99.9% was not currently obtainable, and that a selectivity for X no greater than 99 % should be assumed when calculating the working fluids’ operational lifetime. Hydrogen-storing polymethylpyridylsiloxanes were proposed as energy carrier alternatives to fossil fuels. Polymethylpyridylsiloxanes were considered, in part, due to the expansive liquid ranges of siloxane polymers [-40 ˚C to 250 ˚C]; this would allow the polymethylpyridylsiloxanes to be stored and pumped into vehicles using existing refueling infrastructure. Polymethylpyridylsiloxanes, and analogs thereof, however, were not successfully synthesized and reversibly hydrogenated: either the desired product(s) could not be synthesized, isolated, and/or purified; or, hydrogenation resulted in product decomposition. It was concluded, therefore, that implementing polymethylpyridylsiloxanes as hydrogen-storing liquids is not viable.

abstract: PhD


title: Novel Rac1/Stat3 and Stat5 Pathway in Differentiation and Neoplastic Transformation of Breast Epithelial Cells: Potential Prognostic Markers

contributor:
Elliott, Bruce E.
Raptis, Leda
Microbiology and Immunology

subject:
Breast cancer
Clinical

abstract: Thesis (Ph.D, Microbiology & Immunology) -- Queen's University, 2013-12-24 12:00:40.389

abstract:
Breast cancer is one of the leading causes of death of women in North America. Signal Transducer and Activator of Transcription (Stat)3 and Stat5 are transcription factors involved in normal breast development, and are hyperactivated in 30-50% of breast cancers.

Stat5 is required for breast epithelial cell differentiation and is over-expressed in breast cancers with a more differentiated phenotype. Constitutive over-expression of Stat3 in breast cancer, on the other hand, can drive expression of genes involved in survival, migration and angiogenesis. Our group has previously elucidated a novel activation mechanism of Stat3 by cadherin engagement in densely growing cells. We hypothesize that Stat5 and Stat3 are regulators of the balance between differentiation and transformation of breast epithelial cells: Stat3 activation is modulated by a cadherin/Rac1 pathway, and this may be necessary for differentiation. Stat5 on the other hand may play a role in differentiation independent of cell density. Therefore, Stat3 and Stat5 may turn out to be independent prognostic markers for breast cancer.

We show here, through pharmacological inhibition experiments, that Stat3 is required for differentiation of HC11 breast epithelial cells, measured by β-casein expression. On the other hand, we also show that constitutively active Rac, a molecule downstream of cadherin in the Stat3 activation pathway, blocks the differentiation of breast epithelial cells. Stat5 is upregulated by hydrocortisone, insulin and prolactin, but is unaffected by density. Stat5 is also required for differentiation; moreover we show that expression of activated Stat5 in HC11 breast epithelial cells promotes a more differentiated phenotype. As an initial approach to biomarker development, we have optimized a quantitative analysis method to assess protein expression profiles of clinically relevant robust biomarkers using a 63 tumour breast cancer cohort. Automated quantitative analysis of protein expression in human breast cancer specimens, including target genes of Stat3 and Stat5, cyclin D1 and p21, are statistically similar to manual scoring, and correlate with clinico-pathological parameters. These data provide a vital link between benchwork and clinical studies, and could lead to possible future predictive biomarkers.

abstract: All data is not yet published.

abstract: PhD


title: The interaction between Rad9 and Tousled-like kinase 1 in the cell cycle and the DNA damage response

contributor:
Davey, Scott
Biochemistry

subject:
cancer biology
DNA damage response

abstract: Thesis (Ph.D, Biochemistry) -- Queen's University, 2013-12-24 10:31:57.987

abstract: Genomic integrity is preserved by checkpoints, which are signal transduction pathways that serve to delay cell cycle progression in the presence of DNA damage or replication stress. The heterotrimeric Rad9-Rad1-Hus1 (9-1-1) complex is a proliferating cell nuclear antigen (PCNA)-like clamp that is loaded onto DNA at structures resulting from damage, and is important for initiating and maintaining checkpoint signaling. Rad9 possesses a C-terminal tail unrelated to PCNA that is phosphorylated constitutively and in response to cell cycle position and DNA damage. Previous studies have identified tousled-like kinase 1 (TLK1) as a kinase that may modify Rad9.  This thesis establishes that Rad9 is indeed phosphorylated in a TLK-dependent manner in vitro and in vivo, and that T355 within the C-terminal tail is the primary targeted residue. Phosphorylation of Rad9 at T355 is quickly reduced upon exposure to ionizing radiation before returning to baseline later in the damage response. In addition, TLK1 and Rad9 were shown to interact constitutively, and this interaction is enhanced in chromatin-bound Rad9 at later stages of the damage response. Furthermore, this thesis demonstrates that TLK1 is required for progression through S-phase in normally cycling cells, and that depletion of TLK1 results in a prolonged G2/M arrest upon exposure to ionizing radiation, a phenotype that is mimicked by over-expression of a Rad9-T355A mutant. Given that TLK1 is transiently inactivated upon phosphorylation by Chk1 in response to DNA damage, this work proposes that TLK1 and Chk1 act in concert to modulate the phosphorylation status of Rad9, which in turn plays a role in regulating the DNA damage response.

abstract: PhD


title: Reading Tim Tebow: Conservative Politics and White Power in the Tea Party Era

contributor:
Beamish, Rob
Kinesiology and Health Studies

subject:
Masculinity
NFL
Muscular Christianity
Tea Party Movement
Conservatism
Whiteness

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2013-12-27 13:26:52.995

abstract: In 2011, National Football League (NFL) quarterback Tim Tebow gripped America when the Denver Broncos reeled off a series of thrilling wins in an unlikely playoff run. Surrounding this stretch of Bronco wins was a media frenzy popularly known as “Tebow Mania”. The media explosion around Tebow can be attributed to his perplexing character and the political, cultural and social circumstances in 2011. This thesis is a critical media discourse analysis of Tebow’s sport star identity. I analyze the ways in which Tebow was described during the heights of his popularity during the 2011 NFL season. I argue that Tebow’s sport star identity naturalized ideologies of rightwing conservatism, (rightwing) conservative Christian fundamentalism and white masculinity into “common sense” notions of social life. To accomplish this, I follow cultural studies methodologies that trace Tebow’s rise to prominence within the context of The Tea Party Movement. I outline two dominant narratives that emerged during Tebow Mania to fabricate an American Dream, underdog story. While the first narrative of polarization criticizes and contemplates Tebow’s muscular Christianity, the counter-narrative repackages the polarization of Tebow by celebrating his white racial identity and conservative American values.

abstract: M.A.


title: Development of forest biorefining in Canada: overcoming the feedstock barrier

contributor:
Mabee, Warren
Geography

subject: bioenergy biofuel forestry feedstock transportation biorefining

abstract: Thesis (Master, Geography) -- Queen's University, 2013-12-30 17:39:57.326

abstract: The development of forest-based biorefineries has the potential to both provide a source of sustainable, low carbon fuel and increase the value drawn from wood residues to help revitalize the forest sector.  There has been significant progress toward developing forest biorefining technologies, supported to some extent through government programs, though there are still several barriers to development.  Realization of commercial-scale facilities however, will likely be limited by logistical constraints associated with maintaining a consistent supply of woody feedstock and the high capital cost of constructing the facility. To address this issue, mill clusters with sufficient processing capacity were located and evaluated for their suitability to house a forest biorefinery.  Existing single-entity mill clusters in Canada were identified according to a set of criteria, and provide the basis for the analysis to determine feedstock supply costs and potential availability.  The optimal biorefinery sites within each cluster were identified using a transportation module developed for this study and evaluated according to other factors that would affect the suitability of the site for a large scale forest biorefinery, such as access to markets, other available feedstocks and energy sources.  There were four mill clusters identified in eastern Canada that have the potential to support a commercial forest biorefinery.  A facility that is centrally located within one of the identified clusters would expect to have a feedstock cost ranging from approximately $95 to $110 per odt.  A series of key informant interviews were carried out to further assess the cluster approach to forest biorefinery development.  Interviewees generally agreed that the identified locations could potentially support a commercial biorefinery and suggested there are currently significant volumes of underutilized wood in these regions.  Forest biorefinery development in the cluster regions, especially where there is mixed forest, should be further pursued.

abstract: M.Sc.


title: Microstructural Evolution in ZR and ZR Alloy Excel Under Ion Irradiation

contributor:
Daymond, Mark R.
Mechanical and Materials Engineering

subject:
Zr Alloy Excel
Radiation Induced Damage
Mechaincal and Materials Engineering
Ion Irradaition
Zirconium

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-12-31 23:50:30.352

abstract:
Zirconium and its alloys have been used extensively in both light and heavy water reactors where neutron irradiation is known to cause microstructural evolution, leading to degradation of mechanical properties and dimensional instabilities. Dimensional instabilities due to irradiation growth are particularly crucial for Zr alloy Excel which is the proposed candidate material for the conceptual CANDU-Super Critical Water Cooled Reactors (SCWR) pressure tube. This study employs the in-situ ion irradiation technique and transmission electron microscopy to investigate the irradiation induced microstructural evolution in Zr and Zr alloy Excel.
The current study is presented as a manuscript format dissertation comprised of five manuscript chapters. Chapter 3 reports the formation of irradiation induced prismatic defects directly from cascade collapse in pure Zr at low dose (0.008 dpa) in a temperature range of 300oC-500oC. The morphology and yield of these defects are found to be temperature and dose dependent. In Chapter 4, irradiating Zircaloy-2 under similar conditions to pure Zr, reveals that nucleation rate of small prismatic loops increases, whereas their growth is suppressed which indicates that these defect clusters are not only temperature dependent but also impurity dependent.
Chapters 5, 6 and 7 report the irradiation induced microstructural changes at various temperatures up to a dose of 10 dpa, in several microstructures of Zr alloy Excel, achieved by different solution treatments. The major focus of these experimental studies was the formation of <c>-component loops in α-phase; decomposition of β-phase; and irradiation induced microchemical changes. It was found that nucleation and growth of <c>-component loops is strongly dependent on irradiation temperature, parent microstructure, and presence of alloying elements. <c>-component loops nucleate above a threshold incubation dose which decreases with an increase of irradiation temperature. Energy dispersive X-ray spectroscopy (EDS) mapping on irradiated microstructures revealed the formation of small Sn clusters in α-phase which have a significant effect on the morphology of <c>-component loops. Fe plays an important role in the nucleation of <c>-component loops, as it distributes itself during irradiation either from β-phase or from pre-existing secondary phase precipitates in α-phase. Furthermore irradiation induced decomposition of β-phase was observed in the form of ω-phase precipitation and irradiation induced clustering of alloying elements.

abstract: PhD


title: Do Relationships Matter? An Examination of a School-Based Intergenerational Mentoring Program

contributor:
Craig, Wendy M.
Psychology

subject: Mentor Intergenerational School-Based Youth

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2014-01-02 10:12:55.265

abstract:
Although relationships are central to psychological health throughout the lifespan, not all children have caring adults in their lives that can provide nurturing and stable relationships.  Mentoring was established as a means of providing these essential adult relationships to at-risk children.  Although the history of formal mentoring traces back to the beginning of 20th century America, only recently have systematic investigations of mentoring programs been conducted.  Furthermore, a wide range of mentoring programs across North America have been implemented which has outpaced the research community’s ability to provide evidence-based practice guidelines.  The goal of this dissertation was to contribute to research and practice in the field of youth mentoring.  In the first study I evaluated the effects of participating in a school-based intergenerational mentoring program. Although I did not find benefits of program participation for mentors or mentees, I identified methodological limitations that are important for future studies to take into consideration and determined two key strengths of the program.  In the second study, I compared mentee, mentor, and mentoring coordinator perspectives on mentoring relationship quality and examined how two components of mentor-mentee interactions, relationship dimensions and mentor-mentee shared experiences, were associated with these different perspectives.  I developed an observational rating scale to examine a new framework of relationships dimensions, identified several elements that characterize high quality mentoring relationships, and provided suggestions for how to apply this knowledge to mentor training.  In the last study, I discussed the connection between research and practice in youth mentoring and identified strategies to promote collaborative interactions that empower individuals, build social relationships, and create synergy between researchers and practitioners.
Through my investigation of both mentor-mentee and research-practice relationships, I gained insight into the processes of successful relationship formation and characteristics of long-term relationships.  I encountered several methodological barriers and used these as opportunities to identify strategies for overcoming challenges inherent in mentoring research.  The knowledge gained through this dissertation can be applied by mentoring agencies to develop evidence-based mentor training programs and by researchers and practitioners to form successful research-practice collaborations, which are necessary to continue to further our understanding of youth mentoring.

abstract: PhD


title: An Experimental and Numerical Investigation of Evaporative Spray Cooling for a 45 degree Bend near a Gas Turbine Exhaust

subject:
Computational vs Experimental
spray cooling
exhaust bend
gas turbine exhaust
evaporative cooling
CFD

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2014-01-02 11:02:00.955

abstract:
The research performed in this work investigated evaporative spray cooling systems using water near a 45 degree bends in gas turbine exhaust piping systems. Both experimental data and numerical data were generated with the goal of evaluating the ability of Fluent 6.3.26 to predict the performance of these systems for the purpose of design using only modest computational resources. Three cases were investigated in this research: single phase exhaust flow with no water injection, injecting water before the bend and injecting water after the bend. Various probes were used to measure dry bulb temperature, total pressure and water mass flux of the two phase flow at the exit of the pipe. Seven hole probes and pitot static probes were used to measure single phase flow properties.
Numerical simulations were performed using mass flow boundary conditions which were generated from experimental results. A turbulence model was selected for the simulations based on comparisons of single phase simulations with experimental data and convergence ability. Using Fluent’s discrete phase model, different wall boundary conditions for the discrete phase were used in order to find the model which would best match the evaporation rates of the experimental data. Mass flux values through the exit plane of the pipe were found to be the most reliable of all the two phase data collected.
Results from numerical simulations revealed the shortcomings of the available discrete phase wall boundary conditions to accurately predict the interaction of the liquid phase with the wall. Experimental results for both cases showed extensive areas of the wall which had liquid film layers running down the length of the pipe. Simulations resulted in particles either failing to impact the wall and create a liquid film, or creating a liquid film which was much smaller than the film present in experimental results. This led to 8% and 15% discrepancy in evaporation
amounts between numerical and experimental results for water injection upstream and downstream of the bend respectively. Under-prediction of areas wetted with a wall film in the simulations also led to gross over predictions of wall temperature in numerical results.

abstract: M.A.Sc.