title: Assessing Memory in an Aldehyde Dehydrogenase 2 Knockout Model of Alzheimer's Disease

contributor:
Bennett, Brian M.
Pharmacology and Toxicology

subject:
Alzheimer's
Aldehyde Dehydrogenase 2
Memory

abstract: Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2013-09-26 11:20:00.023

abstract: The study of Alzheimer’s Disease (AD) has been hindered by the absence of animal models of late-onset/age-related AD (also termed sporadic AD) (95% of AD cases) since current transgenic mouse models exhibit pathological changes dependent on overexpression of mutant human genes linked to early-onset, familial AD (5% of cases). Oxidative stress is considered to be a causative factor in age-related AD, and we have found that aldehyde dehydrogenase 2 (Aldh2) null mice exhibit not only oxidative stress, but also display many AD-like pathologies. The current study used behavioral analysis to assess whether Aldh2-/- mice also exhibit memory and cognition deficits. Male and female wild type and Aldh2-/- mice were tested monthly beginning at three months of age, using the open field novel object recognition test (a measure of recognition memory), as well as spontaneous alternations in the Y-maze (a measure of spatial working memory). In both tasks, significant decreases in performance occurred in Aldh2-/- mice by 3.5-4 months of age, and this progressively declined over the next three months compared to wild type mice. Sex-related differences in memory impairment were not observed. These results, together with the findings that AD-like pathologies are also present, suggest that Aldh2-/- mice represent a new, oxidative stress-based model of age-related cognitive impairment and AD. This model may prove useful both for assessing AD therapeutics and for gaining better insight into the pathogenesis of AD.

abstract: M.Sc.


title: Determinants of Cervical Cancer Screening in the Kilimanjaro Region of Tanzania

contributor:
Aronson, Kristan J.
Yeates, Karen
Community Health and Epidemiology

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:
Cervical Cancer
Screening
Global Health

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2013-09-30 14:24:36.139

abstract: Background: Cervical cancer is a leading cause of death in Tanzanian women, with annual age-standardized mortality of 38 per 100,000. While organized screening programs have minimized cervical cancer rates in the developed world, a national prevention program has not yet been instituted in Tanzania. Though screening is available at clinics in the Kilimanjaro region, uptake of these services is reported to be low. The objectives of this thesis were: 1) to describe the knowledge, attitudes and practices of cervical cancer screening in rural and urban Kilimanjaro women, 2) to determine the main barriers preventing women from being screened, and 3) to identify important determinants of screening status and screening acceptability in the population. Methods: A cross-sectional survey was administered to 312 rural and 280 urban women in the region over June-July 2012. The sample was obtained through a multistage random sampling strategy. Descriptive statistics were performed to address Objectives 1 and 2, while multivariate logistic regression models were created using generalized estimating equations to address Objective 3. Results: Awareness of cervical cancer in the sample was high, but women had less knowledge of screening tests for the disease. The proportion of ever-screened women was significantly lower in the rural (4%) than in the urban (8%) sample. The most common barrier in never-screened women was not knowing that screening existed, followed by anticipated cost of the procedure. Travel distance was a more frequent concern in rural women. Older age, being married, cervical cancer knowledge and healthcare access factors were significantly associated with screening status in urban women, while only older age and condom use were associated in rural women. Personal beliefs about risk were associated with screening acceptability in never-screened women. Willingness to be screened was low in urban women with high socioeconomic status. Conclusions: Participation in cervical screening is extremely low in the Kilimanjaro region due to both access-related and personal barriers. While Tanzania awaits a national screening program, the identified determinants may inform regional screening and education initiatives aimed at increasing screening coverage in the Kilimanjaro area.

abstract: Following the thesis's submission for completion of degree requirements, the student will prepare a manuscript from the findings to be submitted for commercial publication.

abstract: M.Sc.


title: Saccadic eye movements and pause/articulation components during a letter naming speed task: Children with and without dyslexia

contributor:
Munoz, Douglas P.
Kirby, John R.
Neuroscience Studies

subject:
Rapid Naming
Phonological Processing
Dyslexia
Orthography
Eye Movements

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2013-09-26 12:24:53.951

abstract:
Naming speed (NS) tasks that measure how quickly and accurately participants can name visual stimuli (e.g., letters) are commonly used to predict reading ability. However, the link between NS and reading is poorly understood. Three methods were used to investigate how NS relates to reading and what cognitive processes are involved: (a) changing stimulus composition to emphasize phonological and/or visual aspects (Compton, 2003); (b) decomposing NS times into pause and articulation components; and (c) analyzing eye movements during a NS task. Participants were in three groups: dyslexics (aged 9, 10), chronological-age (CA) controls (age 9, 10), and reading-level (RL) controls (aged 6, 7). We used a letter NS task and three variants that were either phonologically and/or visually confusing while subjects’ eye movements and articulations were recorded, and examined how these manipulations influenced NS performance and eye movements.
For all groups, NS manipulations were associated with specific patterns of behaviour and saccadic performance, reflecting differential contributions of NS to reading. RL controls were less efficient, made more errors, saccades and regressions, and made longer fixation durations, articulation times, and pause times than CA controls. Dyslexics consistently scored in between controls, except for the number of saccades and regressions in which they made more than both control groups. Overall there were clear developmental changes in NS performance, NS components, and eye movements in controls from ages 6 to 10 that appear to occur more slowly for dyslexics.
Furthermore, pause time and fixation duration were key features in the NS-reading relationship, and increasing visual similarity of the letter matrix had the greatest effect on performance for all subjects. This latter result was demonstrated by the decrease in efficiency and eye-voice span, increase in naming errors, saccades, and regressions, and longer pause times and fixation durations found for all subjects. We conclude that NS is related to reading via fixation durations and pause times; longer fixation durations reflect the greater amount of time needed to acquire visual/orthographic information from stimuli, and longer pause times in children with dyslexia reflect the greater amount of time needed to prepare to respond to stimuli.

abstract: M.Sc.


title: Validation of a Gene-Expression Based Assay for BRCA1 Function

contributor:
Davey, Scott
Pathology and Molecular Medicine

subject:
Breast cancer
Clinical assay
qPCR
BRCA1
Gene expression
Variants of Unknown Significance

abstract: Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2013-09-26 13:13:50.809

abstract:
Breast cancer is a disease that afflicts a significant proportion of women globally. 5-10% of breast cancer cases are linked to inherited polymorphisms in critical genes such as BRCA1, a tumour suppressor essential for genomic stability. A dysfunctional BRCA1 gene can increase breast cancer risk by 60-80%. Previous microarray analysis established that differential gene expression in unperturbed Epstein-Barr virus transformed lymphocyte cell lines (EBV-LCL) was able to distinguish BRCA1 mutation carriers from controls with a high degree of accuracy. A 43-gene radiation-independent classifier for BRCA1 status was constructed.
We hypothesize that this differential gene expression can be observed in a subset of these genes using quantitative PCR (qPCR) in both EBV-LCL and B-lymphocytes isolated from patients with known BRCA1 mutation carrier status.
The 43-gene classifier was analyzed using gene ontology analysis and 4 target genes selected based on predictive value, expression intensity and gene ontology similarity. Genes selected were CXCR3, TBX21, MX2, and IFIT1, with GusB as an endogenous reference gene. EBV-LCL established from known BRCA1 mutation carriers and from BRCA1 wildtype individuals were obtained and RT-qPCR (reverse transcriptase qPCR) performed on isolated RNA. Our results showed significant downregulation of CXCR3 and TBX21 in BRCA1 mutation carriers (p=0.018 and p=0.003, respectively), as expected from previous microarray results. IFIT1, while showing a non-significant upregulation (p=0.183), agreed with the expected trend. MX2 did not show significant differential expression. These results indicate that differential gene expression has the potential to accurately distinguish pathogenic variants, even if it may require EBV immortalization of B-lymphocytes.
To determine whether the assay could be extended to fresh blood samples, B-lymphocytes were isolated from patients with known BRCA1 mutation carrier status from North York General Hospital in Toronto, ON. An optimized protocol to enrich the B-lymphocyte population using magnetic separation was developed for this purpose. RT-qPCR using RNA isolated from these lymphocytes showed no significant differential gene expression in CXCR3 and TBX21. However, a low sample size, use of non-sequenced controls and a need for further qPCR optimization may call these results into question. In addition, problems with blood sample transportation from off-site sources resulted in an unacceptable drop in RNA integrity.
While this gene expression assay may be limited to screening a small number of blood samples, results indicate that may still have clinical relevance that can be explored. This would necessitate further optimization of the qPCR methodology and resolution of the issues surrounding RNA integrity and sample transport.

abstract: M.Sc.


title: Measurement of Lower Extremity Frontal-Plane Alignment and Knee Osteoarthritis Severity Using Photographic and Radiographic Approaches

contributor:
Culham, Elsie
McLean, Linda
Rehabilitation Science

subject:
Frontal Lower-Extremity Alignment
Knee Osteoarthritis

abstract: Thesis (Ph.D, Rehabilitation Science) -- Queen's University, 2013-09-26 13:21:06.097

abstract:
Osteoarthritis (OA) of the knee affects between 5.4% and 38% of older adults and this prevalence is increasing as the population ages and becomes more obese.  As health costs rise, it is important to have accurate and cost-effective methods to assess knee OA and the risk for OA.
One risk factor for progression of knee OA is lower extremity (LE) frontal-plane malalignment.  The first goal of this thesis was to assess the suitability of knee radiographs and LE photographs for the estimation of frontal-plane LE alignment.  In the first study, several versions of the femoral shaft-tibial shaft (FS-TS) angle, assessed from knee radiographs, were compared to the hip-knee-ankle (HKA) angle, assessed from full-length radiographs.  We concluded that the FS-TS angle is not a recommended substitute for the HKA angle, because the association between the two measures differs depending on alignment, OA severity and the method of determining the FS-TS angle.
In the second study, the hip-knee-ankle angle determined from a pelvis-to-ankle photograph (HKA-P) was assessed for its ability to estimate the HKA angle.  The HKA-P angle was reliable and highly correlated to the HKA.  It therefore shows promise as an accurate and cost-effective assessment tool for the estimation of LE alignment.
Commonly-used grading scales for the severity of knee OA seen on a radiograph emphasize just one feature of OA; therefore the second goal of this thesis was to assess the psychometric properties of the unicompartmental osteoarthritis grade (UCOAG), a composite scale which grades several features of OA in the tibiofemoral (TF) compartment.
In the third and fourth studies, the reliability, validity and sensitivity to change of the UCOAG scale was assessed and compared to two commonly-used scales (Kellgren-Lawrence and Osteoarthritis Research Society International joint space narrowing).  The UCOAG scale showed moderate to excellent reliability.  All three scales demonstrated comparable validity and sensitivity to change.  The UCOAG is therefore recommended for the assessment of OA severity and change over time.
This research provides evidence for the use of accurate and cost-effective measures to assess LE alignment using photographs, and TF OA severity using radiographs, for clinical assessment and research purposes.

abstract: PhD


title: Pregnant in Heels: A Critical Analysis of the Ideal, Maternal Body in Celebrity Magazines

contributor:
Burfoot, Annette J.
Sociology

subject:
Maternal Bodies
Libidinal Economy
Bio-Power
Celebrity

abstract: Thesis (Master, Sociology) -- Queen's University, 2013-09-26 13:25:26.234

abstract: Over the past several years, the physical appearance of pregnant and new mothers has been evolving within Western society.  In particular, celebrity mothers who are templates for contemporary ideals within society (Tyler 2011) experience heightened levels of surveillance and normalizing practices.  The shifting ideal, maternal form illustrates how the bodies of women continue to be subjected to discipline and control within society.  Furthermore, the flourishing of consumer culture within some neoliberal societies pressures women to consume in order to fully realize their maternal identity. Increased articulation of individual identity through consumption, coupled with increasingly specific appearance standards, narrow the scope of what idealized motherhood embodies. In order to best investigate the issue of the shifting, ideal maternal form, various issues of tabloid magazines will be analyzed.  Relying on social constructionism in conjunction with Foucault’s theories of the disciplining of docile bodies and biopower, along with Lyotard’s desire-based, libidinal economy, the literature on the public presentation of maternal bodies will be analyzed with focus on newly developed, rigorous appearance and fitness standards for mothers.  Additionally, how these disciplinary practices function within neoliberal climates that champion desire-based consumption, freedom, liberty, individualism and self-subjectification will also be investigated.  A cultural analysis of thirty-seven tabloid publications from 2012 to 2013 will be examined for both visual and written discourse pertaining to the cultural construction of ideal motherhood.  Through this analysis the interplay between the two seemingly contradictory messages of excessive, desire-based consumption and restrictive, corporeal discipline will be explored in order to gain a better understanding of how these incongruous scripts affect the lives of mothers today.

abstract: M.A.


title: Host-Guest Complexes of Cucurbit[7]uril With Cationic Drugs and Amino Acid Derivatives

contributor:
Macartney, Donal H.
Chemistry

subject:
Cucurbit[7]urils
Amino Acid Derivatives
Cationic Drugs

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2013-09-26 14:33:40.063

abstract:
The host-guest chemistry between cucurbit[7]uril (CB[7]) and cationic organic guests of medicinal and biological interest are described in this thesis. In the first part, three cationic steroidal neuromuscular blockers (SNMBs) were studied, along with guests that model their monocationic N-alkyl-N-methylheterocyclic (morpholinium, pyrrolidinium and piperidinium) terminal groups of the SNMBs, and dicationic guests in which the two N-methylheterocyclic rings are linked by a decamethylene chain, modelling a variety of NMBs.  Other cationic drugs related to acetylcholine processes in neuromuscular blockage were also studied. In the second part, the amino acids lysine, and its mono-, di- and trimethylated and acetylated Nε derivatives, and arginine, and mono- and (symmetric and asymmetric) dimethylarginine, were investigated as guests, along with analogs of arginine. The nature and strength of the complexation between CB[7] and these guests in aqueous solution were determined by 1H NMR spectroscopy and ESI mass spectrometry.
The CB[7] showed high binding affinity (KCB[7] = 106-109 M-1) towards the N-alkyl-N-methylheterocyclic cations with a trend of piperidinium > pyrrolidinium > morpholinium, which reflects the relative hydrophobicities of the guests. The CB[7] forms 1:1 and 2:1 host-guest complexes with dicationic model guests, with the CB[7] initially encapsulating the decamethylene chain. The second CB[7] binds to a terminal site, resulting in electrostatic repulsions with the first CB[7], which are resolved by the translocation of the first CB[7] to the opposite terminal site.  This 2:1 binding mode is also observed with CB[7] and the SNMBs, and the trend in KCB[7]  with these SNMB terminal sites is comparable to that observed for the monocationic model guests. The other cationic drugs also form stable host-guest complexes with CB[7], and the binding constants displayed dependences on the size, charge, and hydrophobicity of the guests.
The CB[7] exhibits significant selectivity towards different lysine and arginine derivatives, which can be related to the relative hydrophobicity afforded by the methyl substituents and the positioning of the guest within the CB[7] cavity. The 3500-fold selectivity for Nε,Nε,Nε-trimethyllysine over lysine by CB[7] is the highest observed for a synthetic macrocyclic receptor, while a modest selectivity of symmetrical over asymmetrical dimethylarginine by CB[7] is observed.

abstract: PhD


title: Dynamic Monitoring of Rail and Bridge Displacements Using Digital Image Correlation

contributor:
Take, W. Andy
Hoult, Neil A.
Civil Engineering

subject:
Railway
Bridge
Particle Image Velocimetry
Monitoring
Accuracy
Digital Image Correlation

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-26 15:40:16.744

abstract:
Rail and bridge infrastructure assets are critical elements of Canada’s transportation network and their continued efficient and safe operation is necessary to ensure the nation’s economic livelihood. Monitoring technologies that can detect changes in performance as well as precursors to failure are an important element of ensuring this efficient and safe operation. Digital Image Correlation (DIC) is a monitoring technology that has the potential to provide critical data for infrastructure assessment and to replace various conventional sensors with one integrated monitoring solution.
In this research, the accuracy of DIC is evaluated using numerical, laboratory and field-based experiments. The sources of error of particular relevance to dynamic measurement using DIC are identified as (i) bias error in the sub-pixel interpolation scheme, (ii) the ratio of sample rate to the frequency of the signal being monitoring and (iii) the signal to noise ratio. It is also shown that the chosen sub-pixel interpolation scheme can greatly affect the accuracy of dynamic measurements.
The use of DIC was investigated for field monitoring of both horizontal and vertical railway displacements at sites with good and poor subgrade conditions under dynamic train loading. It is shown that there is a significant benefit to using an absolute displacement measurement system rather than a relative displacement measurement system as the former can capture irrecoverable rail displacements in both the vertical and horizontal directions.
Finally, DIC was also used for field monitoring of a very stiff reinforced concrete bridge during static and dynamic load tests. It is shown that when using DIC for deflection monitoring, corrections may have to be made to compensate for errors such as camera jitter and drift to acquire the most accurate results. Two potential correction methods were the use of a fixed reference point and generating composite images using average pixel intensity values from multiple images. It was found that using a fixed reference point was the optimal choice in this bridge test. It is concluded that DIC can be used as an effective displacement measurement tool for bridge assessment because it shows excellent correlation with linear potentiometer results and it can allow measurements to be taken without having to close the bridge.

abstract: M.A.Sc.


title: Art and the Invention of North America, 1985-2012

contributor:
Jessup, Lynda
Robertson, Kirsty
Art History

subject:
North America
Cultural Diplomacy
Free Trade
Visual and Material Culture

abstract: Thesis (Ph.D, Art History) -- Queen's University, 2013-09-26 20:06:23.882

abstract: This thesis examines visual and material culture in relation to free trade in North America, focusing on cultural production between 1985 and 2012. These dates broadly encompass a period in which the Canadian state entered into progressively larger free trade agreements with neighbouring states, including the United States in 1989 and Mexico in 1994. This period resulted in significant changes to the dominant understandings of North America. I trace the substantial role that art endeavors played in establishing and naturalizing economic integration in the continent. Through discussion of diverse examples of art production, I posit that consideration of the selected artworks and exhibitions is integral to properly assessing histories of free trade in North America. Each chapter deals with a different case study of forms of art production, chosen because they helped promote new understandings of North America after the implementation of the North American Free Trade Agreement. These case studies deal with how exhibitions of modern and contemporary landscape art and exhibitions of indigenous visual and material culture contribute to constructing narratives of North America. They also cover the contemporary art festival inSite, as well as the history of Mexican modern art in Canada. I demonstrate that visual and material culture played an integral role in deploying new understandings of the continent, while concurrently serving as a means to circulate counter-narratives of North America. To foreground Canadian artistic responses to free trade, I insert interstices between every chapter, each focused on a specific work of contemporary video art from the period. These six interstices demonstrate a sustained engagement by Canadian contemporary artists to respond to and comment on North American integration, and thus provide a map to the key issues of neoliberal expansion.

abstract: I am restricting my thesis in order to publish the content with an academic press before it is available to freely download online.

abstract: PhD


title: Beneath the surface electrocardiogram: computer algorithms for the non-invasive assessment of cardiac electrophysiology

contributor:
Akl, Selim
Redfearn, Damian P.
Computing

subject: ECG Algorithms

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2013-09-30 23:54:21.137

abstract:
The surface electrocardiogram (ECG) is a periodic signal portraying the electrical activity of the heart from the torso. The past fifty years have witnessed a proliferation of computer algorithms destined for ECG analysis. Signal averaging is a noise reduction technique believed to enable the surface ECG to act as a non-invasive surrogate for cardiac electrophysiology.

The P wave and the QRS complex of the ECG respectively depict atrial and ventricular depolarization. QRS detection is a pre-requisite to P wave and QRS averaging. A novel algorithm for robust QRS detection in mice achieves a four-fold reduction in false detections compared to leading commercial software, while its human version boasts an error rate of just 0.29% on a public database containing ECGs with varying morphologies and degrees of noise.

A fully automated P wave and QRS averaging and onset/offset detection algorithm is also proposed. This approach is shown to predict atrial fibrillation, a common cardiac arrhythmia which could cause stroke or heart failure, from normal asymptomatic ECGs, with 93% sensitivity and 100% specificity. Automated signal averaging also proves to be slightly more reproducible in consecutive recordings than manual signal averaging performed by expert users.

Several studies postulated that high-frequency energy content in the signal-averaged QRS may be a marker of sudden cardiac death. Traditional frequency spectrum analysis techniques have failed to consistently validate this hypothesis.

Layered Symbolic Decomposition (LSD), a novel algorithmic time-scale analysis approach requiring no basis function assumptions, is presented. LSD proves more reproducible than state-of-the-art algorithms, and capable of predicting sudden cardiac death in the general population from the surface ECG with 97% sensitivity and 96% specificity.

A link between atrial refractory period and high-frequency energy content of the signal-averaged P wave is also considered, but neither LSD nor other algorithms find a meaningful correlation.

LSD is not ECG-specific and may be effective in countless other signals with no known single basis function, such as other bio-potentials, geophysical signals, and socio-economic trends.

abstract: Considering patenting

abstract: PhD


title: Modelling Laser Light Propagation in Thermoplastics Using Monte Carlo Simulations

contributor:
Zak, Gene
Bates, Philip J.
Mechanical and Materials Engineering

subject: Plastic Welding Laser Optics

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-09-27 10:41:08.997

abstract:
Laser welding has great potential as a fast, non-contact joining method for thermoplastic parts. In the laser transmission welding of thermoplastics, light passes through a semi-transparent part to reach the weld interface. There, it is absorbed as heat, which causes melting and subsequent welding. The distribution and quantity of light reaching the interface are important for predicting the quality of a weld, but are experimentally difficult to estimate. A model for simulating the path of this laser light through these light-scattering plastic parts has been developed. The technique uses a Monte-Carlo approach to generate photon paths through the material, accounting for absorption, scattering and reflection between boundaries in the transparent polymer. It was assumed that any light escaping the bottom surface contributed to welding. The photon paths are then scaled according to the input beam profile in order to simulate non-Gaussian beam profiles.
A method for determining the 3 independent optical parameters to accurately predict transmission and beam power distribution at the interface was established using experimental data for polycarbonate at 4 different glass fibre concentrations and polyamide-6 reinforced with 20% long glass fibres. Exit beam profiles and transmissions predicted by the simulation were found to be in generally good agreement (R2>0.90) with experimental measurements. The simulations allowed the prediction of transmission and power distributions at other thicknesses as well as information on reflection, energy absorption and power distributions at other thicknesses for these materials.

abstract: M.A.Sc.


title: Thermal Degradation of PC and PA6 During Laser Transmission Welding (LTW)

contributor:
Bates, Philip J.
Chemical Engineering

subject: Laser Welding Thermoplastics

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2013-09-27 10:45:24.688

abstract:
In laser transmission welding (LTW), a laser beam passes through the laser-transparent part and is absorbed by carbon black (CB) in the laser-absorbent part. This causes a temperature rise at the interface between the parts which leads to melting, diffusion and ultimately joining of the two components. Weld temperatures increase with laser power at a given scan speed. However at higher temperatures, it has been observed that weld strength of LTW starts to decline due to material thermal degradation.
Thermal degradation of materials is a kinetic phenomenon which depends on both temperature and time. Therefore there is no specific temperature for thermal degradation. Thermal gravimetric analysis (TGA) is used to study the thermal degradation of two commonly used thermoplastic materials: polycarbonate (PC) and polyamide 6 (PA6). Each material was studied at two levels of CB. It is shown in this work that increasing the carbon black (CB) level from 0.05 to 0.2wt% has no significant effect on the thermal stability of PA6. However, it is observed that increasing the CB level from 0.05 to 0.2wt% has a noticeable effect on the thermal stability of PC.
The TGA data were then used to obtain the kinetic triplets (frequency factor (k_0), activation energy (E), and reaction model (f(α))) of the materials using a non-linear model-fitting method. These kinetic triplets were combined with temperature-time data obtained from a Finite Element Method (FEM) simulation of the LTW process to predict material degradation during LTW. The predicted degradation was then compared with experimental data. It is found that the predicted onset of material degradation is in good agreement with experimentally observed thermal degradation (of both visually observed degradation onset and weld strength decline) for PC and PA6.
A semi-empirical model based on the FEM temperature data is also developed in this work as a simpler alternative for obtaining LTW maximum temperature-time profiles for prediction of material thermal degradation during LTW. Comparison of the predicted material conversion using temperature-time profile obtained by FEM and the semi-empirical model shows good agreement.

abstract: M.A.Sc.


title: An Exploratory Examination of Coach-Athlete Interactions in Adolescent Team Sport

contributor:
Côté, Jean
Kinesiology and Health Studies

subject:
Decision Making
Coach Behaviour
Youth Sport
Positive Youth Development

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2013-09-27 21:33:32.095

abstract: The purpose of this study was to explore coach-athlete interactive behaviours.  More specifically, it investigated why coaches choose to interact with their athletes, and why coaches interact with their athletes in a particular manner.  Head male coaches, of nine female competitive club soccer teams participated in the current study.  Each coach was videotaped and audiotaped during two practices.  Each video was uploaded to a computer and reviewed.  Coaches then participated in a stimulated recall interview.  During the interview, coaches were shown a total of 15 video clips that included footage of themselves interacting with an individual athlete, group of athletes, and the entire team.  Coaches were asked to expand on the dynamics of these interactions.  The results of the study indicate that when coaches interact with athletes, their reasoning is two-fold: first they decide to interact, and second, they decide the way in which they should interact with their athlete(s) based on several factors.  Coaches interacted for one of four reasons: (1) connection to a larger picture, (2) teachable moments, (3) standards of behaviour, and (4) organization.  The manner in which coaches interacted with their athletes was influenced by four factors: (1) knowledge of the athlete, (2) degree of athlete input, (3) degree of tolerance, and (4) team unit involved.  Together, these results helped to construct a model that illustrates how coaches make decisions with regards to coach-athlete interactive behaviour in context.  Preliminary findings indicate that coaching philosophy permeates this entire process.

abstract: M.Sc.


title: Quantum Optics and the Quantum Jump Technique for Lossy and Non-Orthogonal Systems

subject:
Non-Linear Optics
Non-Orthogonal
Quantum Mechanics
Quantum Jump
QED
Physics
Quantum Electrodynamics
Photonic Crystal
Loss
Photon
Quantum Optics

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-09-27 12:00:10.281

abstract:
In this thesis I develop a formalism for analyzing quantum optics in photonic crystal slab cavities which may be coupled, lossy, and non-orthogonal. Using a tight-binding approximation I find classical coupled-cavity quasimodes which overlap in space and frequency. These classical modes are used to develop a multiphoton basis for quantum optics with non-orthogonal photon states. I develop creation and annihilation operators with a novel commutation relation as a consequence of the nonorthogonality of the quasimodes. With these operators the effective Hamiltonian, number operator, electric field operator and quadrature operators are obtained.
The quantum jump technique is applied to handle the effects of loss. This technique is compared with the master equation, and conditions for the quantum jump technique being preferable are described. The quantum jump technique is implemented numerically, allowing for time-dependent linear and X(2) non-linear pumping.
I use a combination of analytic results and characteristic functions to examine the evolution of coherent and squeezed states in a single lossy quasimode. The analysis is then extended to two nonorthogonal quasimodes. States are investigated using reduced characteristic functions.

abstract: M.Sc.


title: Strategies for Enhanced Bioproduction of Benzaldehyde Using Pichia Pastoris in a Solid-Liquid Partitioning Bioreactor and Integrated Product Removal by In Situ Pervaporation

contributor:
Daugulis, Andrew J.
Chemical Engineering

subject:
Two Phase Partitioning Bioreactor
In Situ Pervaporation
Benzaldehyde
In Situ Product Removal
Flavour and Fragrance
Pichia Pastoris
Polymer Sorption
Whole-Cell Biotransformation

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2013-09-28 17:41:45.458

abstract:
Benzaldehyde (BZA), a biologically derived high-value molecule used in the flavour and fragrance industry for its characteristic almond-like aroma, has also found use in nutraceutical, pharmaceutical, cosmetics, agrochemical, and dye applications. Although, nature-identical BZA is most commonly produced by chemical synthesis, biologically derived BZA, whether by plant material extraction or via microbial biocatalysts, commands much higher prices. The bioproduction of high value molecules has often been characterized by low titers as results of substrate and product inhibition. The current work examined a variety of process strategies and the implementation of a solid-liquid bioreactor partitioning system with continuous integrated pervaporation to enhance the bioproduction of BZA using Pichia pastoris.
Previous work on two-phase partitioning bioreactors (TPPBs) for the biotransformation of BZA using Pichia pastoris has had limitations due to long fermentation times and unutilized substrate in the immiscible polymer phase, contributing to complications for product purification. To reduce fermentation times, a mixed methanol/glycerol feeding strategy was employed and reduced the time required for high-density fermentation by 3.5 fold over previous studies. Additionally, because BZA and not the substrate benzyl alcohol (BA) had been found to be significantly inhibitory to the biotransformation reaction, a polymer selection strategy based on the ratio of partition coefficients (PCs) for the two target molecules was implemented. Using the polymer Kraton D1102K, with a PC ratio of 14.9 (BZA:BA), generated a 3.4 fold increase in BZA produced (14.4 g vs. 4.2 g) relative to single phase operation at more than double the volumetric productivity (97 mg L-1 h-1 vs. 41 mg L-1 h-1). This work also confirmed that the solute(s) of interest were taken up by polymers via absorption, not adsorption.
BZA and BA cell growth inhibition experiments showed that these compounds are toxic to cells and it was their accumulation rather than low enzyme levels or energy (ATP) depletion that caused a reduction in the biotransformation rate. For this reason, the final strategy employed to enhance the bioproduction of benzaldehyde involved in situ product removal by pervaporation using polymer (Hytrel 3078) fabricated into tubing by DuPont, Canada. This aspect was initiated by first characterizing the custom-fabricated tubing in terms BZA and BA fluxes. The tubing was then integrated into an in situ pervaporation biotransformation and was shown to be effective at continuous product separation, using 87.4% less polymer by mass in comparison to polymer beads in conventional TPPB operation, and improved overall volumetric productivity by 214% (245.9 mg L-1 h-1 vs. 115.0 mg L-1 h-1) over previous work producing BZA.

abstract: M.Sc.


title: Cone Penetration Testing and Hydrogeological Monitoring of a Retrogressive Landslide in Champlain Sea Clay

contributor:
Take, W. Andy
Civil Engineering

subject:
landslide
cone penetration testing
piezometers
geotechnical investigation

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-27 14:13:40.196

abstract:
Champlain Sea Clay (also known as Leda Clay) is a sensitive marine clay that was deposited within the limits of the Champlain Sea transgression during the final retreat of the Laurentide ice sheet. Upon isostatic rebound, the watersheds incised deep river valleys throughout the Ottawa region. These sensitive clay river banks have been shown to be highly susceptible to large retrogressive landslides. A cone penetration testing and hydrogeological program was developed in this thesis to characterize a retrogressive landslide along a creek valley consisting mainly of Champlain Sea Clay. As Champlain Sea Clay has been commonly shown to consist of banded layers, a 2 cm2 piezocone, and 5 cm2, 10 cm2 and 15 cm2 CPTu cones were used to demonstrate that the slightly larger 5 cm2 penetrometer was the most practical size for investigating landslides in Champlain Sea Clay. In doing so, the 5 cm2 cone was capable of high resolution stratigraphic profiling, locating remoulded layers for slip surface detection and characterizing the Champlain Sea Clay landslide near Ottawa.
Due to the significant effects of the pore pressure distribution on slope stability and retrogressive behavior, a long term hydrogeological program was initiated which defined the ground water regime and real-time pore pressure data during a retrogressive landslide event. The seasonal change in the ground water regime from rapid snowmelt has shown to be a significant hydrogeological influence on triggering a retrogressive landslide along Mud Creek.  With regular monitoring over multiple seasons, the seasonal pore pressure changes can be used to further understand the long term development of retrogressive landslides in Champlain Sea Clay.

abstract: The preliminary results from a long term monitoring program are outlined in this thesis. Thus, the preliminary findings may jeopardize future projects if publicly accessible.

abstract: M.A.Sc.


title: Do Cardiorespiratory Fitness and Abdominal Obesity Mediate the Exercise-Induced Change in Insulin Sensitivity in Older Adults?

contributor:
Ross, Robert
Kinesiology and Health Studies

subject:
Insulin sensitivity
Aging
Exercise
Cardiorespiratory fitness
Abdominal obesity

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2013-09-27 14:53:00.796

abstract:
Aging is associated with increased insulin resistance, a condition in which the tissue response to insulin-stimulated glucose uptake is reduced. Insulin resistance is a strong predictor of disease and mortality. Aging is also associated with a decline in physical activity, lower cardiorespiratory fitness (ability to deliver oxygen to active muscles during exercise), and increase in abdominal fat. Both low cardiorespiratory fitness (CRF) and excess abdominal fat are associated with reduced insulin sensitivity in older adults. Improvements in CRF and abdominal obesity through exercise training may be responsible for improvement in insulin sensitivity.
	Several investigations have reported that changes in CRF and abdominal obesity through exercise are associated with changes in insulin sensitivity. To our knowledge, no prior study has assessed whether change in CRF or abdominal fat alone explains the association between exercise and improvement in insulin sensitivity in older adults. Our findings suggest that improvement in CRF may not explain the exercise-induced change in insulin sensitivity. The improvement in insulin sensitivity from exercise is explained through a decrease abdominal fat that also occurs with exercise. Additionally, improvements in waist circumference, a surrogate measure for abdominal obesity, and body mass index together explained a large portion of exercise-induced change in insulin sensitivity compared to either variable alone.
Our findings suggest that exercise combined with a healthy diet will improve insulin resistance, a risk factor for development of type 2 diabetes and cardiovascular disease in older adults. Our findings suggest that the reduction in abdominal obesity is the conduit by which exercise improves insulin sensitivity in older adults. Although CRF is not related to exercise-induced change in insulin sensitivity, change in CRF from exercise has been reported to decrease risk for other health conditions, such as hypertension and all-cause mortality. Our findings suggest that clinicians should measure both waist circumference and body mass index when evaluating the effectiveness of a lifestyle-based treatment strategy for improving insulin resistance and its associated health outcomes in older adults.

abstract: M.Sc.


title: Continuously Improving in Tough Times: Overcoming Resource Constraints With Positive Psychological Resources

contributor:
Raver, Jana
Management

subject:
Resource Constraints
Cognitive Appraisals
Psychological Capital
Continuous Improvement

abstract: Thesis (Ph.D, Management) -- Queen's University, 2013-09-27 18:02:23.883

abstract: Individuals and organizations must continuously improve to succeed in today’s competitive economic climate, yet a major dilemma in tough economic conditions is that the resources needed to support such proactive improvement behaviors are limited. Existing theories on organizational resources, stressors, and continuous improvement are relevant yet insufficient for answering the important question of how individuals remain motivated to pursue continuous improvement activities despite minimal organizational resources to support them. Therefore, the goal of this dissertation was to build and test theory on this phenomenon. Inspired by full-cycle research, I began this program of research with a phenomenological study of employees in a manufacturing environment to better understand their appraisals regarding continuous improvement under resource-constrained conditions. The results highlighted the ways in which employees interpret constraints as either a threat or a challenge, and how positive psychological capital (PsyCap) guides these interpretations and subsequent continuous improvement. Informed by this rich data, I proposed a synthesized theoretical model which was tested in two separate contexts. First, I conducted a time-lagged survey study in another resource-constrained environment that demands continuous improvement, namely entrepreneurs launching a new business. To exert more control and to enhance the generalizability of this research, I then conducted an online experiment with participants from various industries and backgrounds. The results of these studies largely supported the theoretical model, documenting in particular the importance of individuals’ challenge appraisals for their ensuing continuous improvement behaviors. The benefits of individuals’ positive psychological resources as a way to enhance the perceived learning opportunities from resource constraints (i.e., challenge appraisal) were also illustrated. Threat appraisals did not produce the expected effects in this context of continuous improvement, and as such, the theoretical model was refined further. Collectively, this research provides answers to the important question of how individuals can find ways to proactively improve in the face of resource constraints, which is a timely and relevant topic across contemporary organizational contexts today.

abstract: PhD


title: On the Performativity of Economics

contributor:
Sismondo, Sergio
Philosophy

subject: Performativity Economics

abstract: Thesis (Master, Philosophy) -- Queen's University, 2013-09-28 08:05:52.036

abstract:
This project seeks to deepen the understanding of economic “performativity” – the effects of economic theory and models on the economy - by examining the history of financial markets and the relationship between economic and political forces. Chapter One demonstrates how the culture of finance (and economics, more generally) began changing in 1950 from methods that aimed in the production of epistemologically true, descriptive statements to abstract theories that illuminated the potentials of markets. As a result, economics was able to provide the mechanisms necessary to transform markets for the first time.
	Chapter Two demonstrates that this departure from orthodox methods birthed a new field of research concerning the ability of economics to construct theoretically described worlds: performativity. This chapter demonstrates that all conceptions of performativity are able to be organized into weak and strong claims, being further united by their depiction of economics as an independent force that comes up against external forces in periods of market emergence and transformation. Interestingly, a dichotomy emerges between performativity and political-cultural approaches to understanding economies: the former claims economics is the force that practically transforms markets and the latter claims transformation occurs through mediation of political and institutional interests.
	It is the purpose of Chapter Three to unveil a new context to understand economic performativity. It will first be demonstrated that there exists little evidence for the performative claim that economics is a force unto itself: instead, economics is utilized as tool to provide organization and stability for actors in periods of market transformation and as such, relies on external forces for performative success. Reconceptualizing performativity in this way addresses many critiques against variations of the performative thesis and suggests that the dichotomization between performative and political-cultural approaches may be reconciled, illuminating a more plausible account of how economics interacts with its objects. It is concluded that performative accounts of economics ought to be subsumed within political-cultural approaches to understanding economic organization.

abstract: M.A.


title: Identifying faking on self-report personality inventories: Relative merits of traditional lie scales, new lie scales, response patterns, and response times

contributor:
Holden, Ronald R.
Psychology

subject:
faking detection
personality assessment

abstract: Thesis (Master, Psychology) -- Queen's University, 2013-09-28 11:00:11.347

abstract: The use of personality tests throughout Canadian society is based on the assumption that their results are valid. However, research has shown that individuals can, and do, fake their responses on personality inventories. Individuals may fake good, emphasizing their positive characteristics, or fake bad, emphasizing negative characteristics, in order to obtain a desired outcome. Recent research has provided support for a congruence model of faking, which states that schema-consistent responses are provided more quickly than schema-inconsistent responses. Faking successfully, without being detected by validity indices, requires balancing favourable and unfavourable responses, regardless of the faking schema a participant adopts. This demand results in cognitive fatigue over time, producing increasingly unbalanced response patterns. Two studies were conducted to evaluate the efficacy of the congruence and cognitive overload models of faking in detecting instructed faking, and to examine whether these models or the newly developed Faking Response Strategy Scales provide added value in detecting faking relative to currently established gold-standard measures. Results showed that all of the self-report scales examined—whether traditional or new—were valid detectors of faking, which supports their ongoing use. However, results highlighted the weakness of the Impression Management subscale of the Balanced Inventory of Desirable Responding, the current gold-standard in the field, in providing added value relative to other scales. Response latency data supported the congruence model of faking, but results for the cognitive overload model were mixed: Study 1 data supported the cognitive overload model, but time constraints introduced in Study 2 seem to have caused random responding, rather than increasing cognitive overload as was intended. Results supported a multidimensional model of faking, and show that adding measures of response latency and response pattern can enhance the ability of traditional measures to detect faking. These findings have important theoretical and practical implications for methods of detecting faking and for the understanding of cognitive processes underlying faking.

abstract: M.Sc.


title: Wireless Sensor Network Platform for Harsh Industrial Environments

contributor:
Hassanein, Hossam S.
Computing

subject: PnP Harsh Software Zigbee Bluetooth Wireless Industrial DASH7 Radio Communication Environment Power Sensor Microcontroller Rugged Application Transceiver Harvesting Platform Networks Syncrude Zigbee Ultrasound Sprouts Architecture Hardware

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2013-09-28 16:14:48.223

abstract: Wireless Sensor Networks (WSNs) are popular for their wide scope of application domains ranging from agricultural, medical, defense, industrial, social, mining, etc. Many of these applications are in outdoor type environments that are unregulated and unpredictable, thus, potentially hostile or physically harsh for sensors. The popularity of WSNs stems from their fundamental concept of being low cost and ultra-low power wireless devices that can monitor and report sensor readings with little user intervention, which has led to greater demand for WSN deployment in harsh industrial environments. We argue that there are a new set of architectural challenges and requirements imposed on the hardware, software, and network architecture of a wireless sensor platform to operate effectively under harsh industrial environments, which are not met by currently available WSN platforms. We propose a new sensor platform, called Sprouts. Sprouts is a readily deployable, physically rugged, volumetrically miniature, modular, network standard, plug-and-play (PnP), and easy to use sensor platform that will assist university researchers, developers, and industrial companies to evaluate WSN applications in the field, and potentially bring about new application domains that were previously difficult to accomplish using off the shelf WSN development platforms. Therefore, we addresses the inherent requirements and challenges across the hardware, software, and network layer required for designing and implementing Sprouts sensor platform for harsh industrial environments. We fully implement the hardware, network, and software architecture for the Sprouts platform and verify that they meet the requirements for harsh environments. We deploy the Sprouts platform customized with our PnP ultrasound sensor module in an industrial application to monitor the health conditions of Syncrude's vibration screens operating under extreme harsh conditions. Sprouts has been showcased in OCE Discovery 2011, and has been proven to be extremely valuable for industrial mining companies such as Syncrude.

abstract: PhD


title: Investigations into the Notion of Sculptors’ Drawings as a Type in Renaissance Tuscany

contributor:
McTavish, David
Art History

subject: Sculpture Drawing

abstract: Thesis (Master, Art History) -- Queen's University, 2013-09-28 21:18:45.79

abstract: The notion of a sculptural type of drawing is often summarily included in critical literature. These references tend to be brief and regularly contradict one another. Furthermore, drawings made by Tuscan sculptors of the sixteenth century are often neglected altogether. This thesis investigates the notion of a sculptural type of drawing and attempts to understand more clearly the appearance and purpose of drawings made by sixteenth-century sculptors working in central Italy. In order to understand this notion, the history of drawings for sculpture and the literature related to them should be examined. Individual artists from whom a number of drawings survive must be studied separately before being related to one another as a group. This investigation utilizes several methodologies: the early history of drawings for sculpture is recreated from information contained in contemporary written documents and contracts; the literature related to the characterization of inherently sculptural qualities is reevaluated against the surviving visual material; the attributions made to lesser-known sixteenth-century sculptors are scrutinized; and, finally, the drawings executed by sculptors are placed in the broader context of sixteenth-century draughtsmanship. This investigation reveals that some drawings exhibit a functional approach that explores the challenges of preparing a three-dimensional work of art. Such an approach is, however, not unique to sculptors, whose drawings employ an approach that cannot be separated from those by painters. These similarities are significant because they reveal several misunderstandings concerning graphic characteristics often understood to be inherently sculptural, and a history of incorrect attributions based on these assumptions.

abstract: M.A.


title: “Live Through This With Me”: Memoirs of Erotic Dance and Agency

contributor:
Tolmie, Jane
Gender Studies

subject:
Sex Work
Erotic Dance
Whore Feminism
Discourse Analysis
Labour

abstract: Thesis (Master, Gender Studies) -- Queen's University, 2013-09-28 21:16:23.247

abstract: This project is a discourse analysis of first-person and ethnographic writings published between the years 2000 to 2012, written by cis-gendered women who have worked or are working as erotic dancers. Utilizing frameworks of “whore feminism” and whiteness I argue that the works under examination within this project assail the victim/agent dichotomy that has historically dominated discourses surrounding sex workers, which ignore what erotic dancers themselves have to say about female empowerment and how they choose to define themselves. By examining the issues of self-presentation that arise within the context of autobiographical work, I interrogate the tensions inherent within the erotic dance industry surrounding assumed motivations for engaging in the industry; measurements of success for erotic dancers; and how stigmatization impacts the lives of dancers and their loved ones. The project highlights ways in which erotic dance memoirs at once open up new critical and theoretical spaces and also problematically reinforce patriarchal stereotypes.

abstract: M.A.


title: Structure and Properties of Self-Assembled Sub-Micron Thin Nafion® Films

contributor:
Karan, Kunal
Docoslis, Aristides
Chemical Engineering

subject:
Surface Wettability
PEFC
Annealing Effect
Substrate Effect
Nafion Ultrathin Film
X-Beam Damage
Electrochemical Impedance Spectroscopy
Proton Conductivity

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2013-09-29 12:36:19.05

abstract:
This thesis is concerned with the study of morphology and properties of sub-micron thin Nafion® films.  The motivation of the work arises from the need to characterize the 4 -10 nm thin ionomer films in the catalyst layer of polymer electrolyte fuel cell (PEFC).
A protocol for the fabrication of self-assembled ultra-thin Nafion® films on planar substrates was successfully developed. Films of thickness ranging 4 nm-300 nm, determined by three different techniques - variable angle spectroscopy ellipsometry (VASE), atomic force microscope (AFM) and x-ray photo-electron spectroscopy (XPS), could be reproducibly generated on SiO2/Si wafer. The 4 nm thin film is one of the thinnest, continuous film of Nafion® ever reported. This is the first time that the structure/properties of such thin Nafion® film have been investigated.
An interesting finding is the thickness-dependent structure and property of these films. Films with thickness <55 nm exhibited hydrophilic-free surface but thicker films (>55 nm) had hydrophobic surface. Similarly, sub-55 nm films had a lower and thickness-independent protonic conductivity compared to thicker films that exhibited thickness-dependent conductivity. Anomalously high water uptake (by quartz crystal microbalance) and swelling (by ellipsometry) of sub-55nm films indicate that low conductivity is not due to low water content However, differences in surface morphology were observed by the AFM phase contrast analysis. The lack of ionic domain was also observed in the thinner films (4-30 nm) from the grazing incidence small x-ray scattering (GISAXS) experiments.
Thermal annealing over a range of temperature (110-160 oC) revealed a dramatic switching of the film surface from hydrophilic to hydrophobic was observed for sub-55 nm films with lower thickness film requiring higher annealing temperature. Bulk proton conductivity was significantly reduced after annealing for all films. An interesting finding was the regeneration of conductivity after to prolonged liquid water exposure and a corresponding switching back of the surface to hydrophilic. The thickness-dependent structure/property of ultra-thin Nafion® films is attributed to substrate induced confinement effect.
Self-assembly of Nafion® on various substrates (SiO2, carbon, Pt and Au) was studied. The ionomer/substrate interaction and resulting film morphology followed a trend with respect to substrate surface energies and Nafion® dispersion compositions.

abstract: PhD


title: R v NS 2012 SCC 72 –  Assessing the Contours of the Freedom to Wear the Niqab in Canada

contributor:
Robinson, Darryl
Law

subject:
Niqab
Religious Freedom

abstract: Thesis (Master, Law) -- Queen's University, 2013-09-29 20:00:52.439

abstract: This thesis uses the recently decided R v NS to assess the contours of the freedom to wear the niqab, as part of religious freedom, in Canada. By criticizing the majority and concurring  opinions I argue that, properly understood, a witness’s religious freedom should protect her from an order to unveil when she is testifying in court. I show that the concurring opinion holds the witness to an illiberal, unfair standard of personal behaviour that fails to respect the witness’s religious freedom. I show that the majority’s decision, though following a justified liberal process of balancing rights, failed to protect NS’s meaningful choice to practice her religion, a standard set by the court in Hutterian Brethren. I then assess the broader implications of R v NS. I argue that in theoretical terms R v NS reaffirms Canada’s commitment to a liberal system of reciprocal rights and rejects a perfectionist approach according to which societal values can override rights. These theoretical lessons are then applied to other policies regulating the veil. I argue that despite its shortcomings, R v NS should generate optimism that perfectionist policies will be rejected and that the veil will only be limited minimally and only when the limit is necessary to uphold other legitimate aims.

abstract: LL.M.


title: Modulating the gut microbiota with a synthetic stool “MET-1”: protective effects in animal models of antibiotic associated colitis

contributor:
Petrof, Elaine
Microbiology and Immunology

subject:
Salmonella enterica serovar Typhimurium
Antibiotic associated colitis
Synthetic stool
Clostridium difficile

abstract: Thesis (Master, Microbiology & Immunology) -- Queen's University, 2013-09-29 21:18:18.966

abstract: Antibiotics disrupt the normal balance of the gut microbiota and may subsequently reduce colonization resistance, allowing pathogenic bacteria to colonize and cause disease. By re-introducing normal microbiota from a donor, colonization resistance can be restored. Based on this premise, a complex mixture, “microbial ecosystem therapeutic-1” (MET-1) containing 33 strains of commensal bacteria was derived from the stool of a healthy human donor. This gut microbial ecosystem has been successfully used to treat two patients infected with C. difficile, but mechanisms of action of the beneficial effects of MET-1 were undefined. An infectious antibiotic-associated mouse model of S. typhimurium and a germ free mouse model of C. difficile infection were utilized to determine the therapeutic effect of MET-1. In the S. typhimurium model, female C57BL/6 mice were pretreated with oral streptomycin prior to receiving MET-1 or vehicle control. When S. typhimurium infected mice were pretreated with MET-1, weight loss was attenuated (-3.5% vs. -6.8%; p<0.05). Serum cytokine levels of TNF-α, MIP-1β, IL-3 and GM-CSF were all significantly reduced. The S. typhimurium bacterial loads in the spleen were decreased in mice pretreated with MET-1 (9190 CFU/g vs. 25,438 CFU/g; p<0.05). Verified using a time-kill assay, MET-1 was bactericidal against S. typhimurium. These results showed that MET-1 could have attenuated the infection by inhibiting the growth of S. typhimurium. Germ-free, female Swiss Webster mice were pretreated with MET-1 or vehicle control prior to infection with C. difficile strain 027.  In infected mice that were pretreated with MET-1 weight loss was attenuated, (-2.43% vs. -13.35%; p<0.05)  and serum cytokine levels of TNF-α, IL-1β, IL-6, GM-CSF, MCP-1, MIP-1α and MIP-1β  were all significantly reduced. The C. difficile bacterial loads in the cecum were reduced in mice pretreated with MET-1 (1.1x106 CFU/g vs. 1.9x108 CFU/g; p<0.05). In this model MET-1 was able to restore colonization resistance and therefore attenuate the C. difficile infection. Therefore, using a complex microbial community could restore colonization resistance against two different pathogens, S. typhimurium and C. difficile. In the future, MET-1 could be used as a prophylactic in conjunction with antibiotics to ensure colonization resistance is maintained against pathogenic bacteria.

abstract: Since MET-1 is under patent, Parteq has requested the thesis to be restricted for 6 months, including the abstract.

abstract: M.Sc.


title: Second Harmonic Generation of Chiral-Modified Silver Nanoparticles

subject:
Second Harmonic Generation
Silver Nanoparticles
Nonlinear Optics
Chiral

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-09-29 21:27:23.112

abstract:
Chiral molecules, which exist under enantiomers with non-mirror-symmetrical structures, have been the subject of intense research for their linear and nonlinear optical activities. Cysteine is such a chiral amino acid found as a building block of proteins throughout human bodies. Second harmonic generation (SHG) has been considered to investigate chiral molecules. SHG from metallic nanoparticles is promising for nanoplasmonics and photonic nanodevice applications. Therefore, it’s desirable to combine and study nonlinear properties due to both chirality and metallic nanoparticles, and help developing an alternatively optical diagnostic of chiral molecules.
Our experiments are carried out with the FemtoFiber Scientific FFS laser system. SHG of silver nanoparticles (Ag NPs) modified by either L-Cysteine (L-C) or D-Cysteine (D-C) is observed, where L-Cysteine and D-Cysteine are a pair of enantiomers. Ag NPs are deposited through Vacuum Thermal Evaporation, controlled under different deposition thicknesses. UV-Vis/IR spectra and AFM are used to characterize Ag NPs under different conditions. Transmitted SHG measurements dependent on incidence are recorded with standard lock-in techniques.
Deposition thickness of vacuum thermal evaporation plays an important role in forming diverse Ag NPs, which strongly imparts the intensity of SHG. Second harmonic intensity as a function of the incident angle presents similar results for Ag NPs with or without L-Cysteine or D-Cysteine modification, in the output of p- and s-polarization. However, we monitor reversed rotation difference in second harmonic intensities at linearly +45° and -45° polarization for L-C/Ag NPs and D-C/Ag NPs, while there’s no difference at linearly +45° and -45° polarization for Ag NPs alone. This optical rotation difference in SHG is termed as SHG-ORD. Also, for second harmonic light fixed at p-polarization, L-C/Ag NPs and D-C/Ag NPs exhibit a reversely net difference for SHG excited by right and left circular polarization, which is termed as SHG-CD. Experiments on SHG-ORD of chiral-modified Ag NPs by a mixture of L-Cysteine and D-Cysteine further help verifying the existence of chirality in chiral-modified Ag NPs.
As a conclusion, SHG efficiently probed and distinguished L-Cysteine from D-Cysteine in chiral-modified Ag NPs.

abstract: M.Sc.


title: Species response to rapid environmental change in a Subarctic pond

contributor:
Arnott, Shelley E.
Biology

subject:
Phenotypic Plasticity
Microevolution
Salinity
Subarctic
Daphnia
Zooplankton
Environmental Change

abstract: Thesis (Master, Biology) -- Queen's University, 2013-09-29 21:54:34.881

abstract:
Unprecedented rates of anthropogenic environmental change have resulted in dramatic decreases in biodiversity worldwide. In order to persist during changes in both the abiotic and biotic environment resulting from anthropogenic stressors such as climate change and habitat degradation, populations must be able to respond or face extirpation. Predicted population-level responses to environmental change include i) range shifts as individuals disperse into more suitable regions, ii) phenotypic plasticity allowing for shifts in the mean phenotype of the population or iii) microevolution resulting from a genetic change within the population. The goal of this thesis is to assess how species within a community respond to a dramatic change in the environment.
	This study used the sediment record of a Subarctic pond to investigate the impacts of a rapid increase in salinity on two species of the crustacean zooplankton Daphnia. One species, Daphnia tenebrosa, was unable to persist in the high salinity conditions and is believed to have been extirpated from the system. The other species, Daphnia magna, was tolerant of the new environmental conditions and was present throughout the sediment record.  To investigate the changes in life history of D. magna, resting eggs from the sediment were hatched to compare iso-female lines from pre- and post-disturbance time periods. No differences were observed between the clone lines, suggesting that phenotypic plasticity allowed D. magna to persist despite the rapidly changing environmental conditions, and that microevolution in salinity tolerance may not have occurred in this population.
	This study suggests that, in environments with moderate levels of post environmental change, pre-existing phenotypic plasticity may play a greater role than microevolution in species response to environmental changes. However, not all species from a community display the same response to environmental changes, as seen in this study with the extirpation of D. tenebrosa. To better understand how communities will be affected by future environmental change, further investigations need to be made on what factors influence species response. Identifying species response may allow conservation efforts to focus on species that are unlikely to adapt to environmental change, and are most at risk.

abstract: M.Sc.


title: Implementation of Evidence in Nursing Practice: the Role and Process of Facilitation

contributor:
Harrison, Margaret B.
Nursing

subject:
Guideline Implementation
Evidence-Based Practice
Facilitation
Nursing

abstract: Thesis (Ph.D, Nursing) -- Queen's University, 2013-09-29 23:34:20.869

abstract:
Background: Moving the latest evidence from research into nursing practice remains a challenge. We are only beginning to recognize the processes involved and little is known as to which approaches are effective in different contexts. Facilitation is an intervention that involves helping practitioners recognize what it is they need to change in practice and how to make these changes to incorporate evidence into practice.
Objective: To describe the role, function, and practice of facilitation in moving evidence into nursing practice. A secondary element is to determine if a provisional facilitation framework, developed to reflect the concept in guideline adaptation and the early stages of implementation, accurately depicts facilitation in the context of actual implementation.
Methods: The thesis employs an emergent mixed-methods design and is composed of two phases each with multiple components. The first phase explores the conceptual, theoretical, and experiential foundations of facilitation and examines: (1) how the concept has evolved over 16 years in a comprehensive literature review, (2) facilitation as described by experienced nurses in guideline implementation, and (3) how facilitation relates to other guideline implementation interventions in a review of studies included in an existing systematic review. The second phase describes the practical foundations of facilitation and follows the facilitation occurring naturally over time in a guideline implementation involving front-line nurses at the point of care.
Results: The comprehensive review provides a description of how facilitation has evolved and presents a current synopsis of the state of knowledge regarding facilitation. The conceptual, theoretical, and empirical understandings of the concept were integrated with the practical foundations to confirm and refine the framework to reflect facilitation across the continuum from guideline adaptation to implementation. The revised framework is displayed and represents a comprehensive view and understanding of facilitation of evidence-based practice in nursing from multiple perspectives.
Conclusions: The detail in the revised framework provides a useful guide for practitioners and organizations in planning for change. Further testing is required to determine its applicability and usability in the practice setting.

abstract: I want to restrict the thesis until the remaining manuscripts are submitted and under review at the selected journals.

abstract: PhD


title: A Functional, Comparative and Clinical Analysis of Sperm-Borne Oocyte Activating Factor, PAWP

contributor:
Oko, Richard
Anatomy and Cell Biology

subject:
PLCz
Fertilization
Sperm
YAP
WWI Domain
Oocyte Activation
Intracytoplasmic Sperm Injection
Assisted Reproductive Technologies
Infertility
PAWP

abstract: Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2013-09-29 23:45:35.395

abstract: Successful fertilization depends upon the activation of metaphase II arrested oocytes by sperm-borne oocyte activating factor (SOAF). Failure of oocyte activation is considered as the cause of treatment failure in a proportion of infertile couples. SOAF induces the release of intracellular calcium in oocyte which leads to meiotic resumption and pronuclear formation. Calcium release is either in the form of single calcium transient in echinoderm and amphibian oocytes or several calcium oscillations in ascidian and mammalian oocytes. Although the SOAF attributes are established, it is not clear which sperm protein(s) play such role. Sperm postacrosomal WW binding protein (PAWP) satisfies a developmental criteria set for a candidate SOAF. This study shows that recombinant human PAWP protein or its transcript acts upstream of calcium release and fully activates the amphibian and mammalian oocytes. Interference trials provided evidence for the first time that PAWP mediates sperm-induced intracellular calcium release through a PPXY/WWI domain module in Xenopus, mouse and human oocytes. Clinical applications of PAWP were further investigated by prospective study on the sperm samples from patients undergoing intracytoplasmic sperm injection (ICSI). PAWP expression level, analyzed by flow cytometry, was correlated to ICSI success rate and embryonic development. This study also explored the developmental expression of the other SOAF candidate, PLCζ in male reproductive system and its function during fertilization. Our findings showed for the first time that PLCζ most likely binds to the sperm head surface during epididymal passage and is expressed in epididymis. We demonstrated that PLCζ is also compartmentalized early in spermiogenesis and thus could play an important role during spermiogenesis. Detailed analysis of in vitro fertilization revealed that PLCζ disappears from sperm head during acrosome reaction and is not detectable during sperm incorporation into the oocyte cytoplasm. In conclusion, this dissertation provides evidence for the essential non-redundant role of sperm PAWP in amphibian and mammalian fertilization; recommends PAWP as a biomarker for prediction of ICSI outcomes in infertile couples; and proposes that sperm PLCζ may have functions other than inducing oocyte activation during fertilization.

abstract: We have current patents as well as publications under review for this thesis. Therefore, this document is highly confidential and needs to be restricted from access at the moment.

abstract: PhD


title: Static Recovery Modeling of Dislocation Density in a Cold Rolled Clad Aluminum Alloy

contributor:
Diak, Bradley J.
Mechanical and Materials Engineering

subject:
Recovery
Dislocation Density
Hardness
Clad Alloy
pseudo-Voight
x-ray line broadening
Aluminium
Annealing

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-10-02 10:19:10.279

abstract: Clad alloys feature one or more different alloys bonded to the outside of a core alloy, with non-equilibrium, interalloy interfaces.  There is limited understanding of the recovery and recrystallization behaviour of cold rolled clad aluminum alloys.  In order to optimize the properties of such alloys, new heat treatment processes may be required that differ from what is used for the monolithic alloys.  This study examines the recovery behaviour of a cold rolled Novelis FusionTM alloy containing an AA6XXX core with an AA3003 cladding on one side.  The bond between alloys appears microscopically discrete and continuous, but has a 30 m wide chemical gradient.   The as-deformed structure at the interalloy region consists of pancaked sub-grains with dislocations at the misorientation boundaries and a lower density organized within the more open interiors.   X-ray line broadening was used to extract the dislocation density from the interalloy region and an equivalently deformed AA6XXX following static annealing using a modified Williamson-Hall analysis. This analysis assumed that Gaussian broadening contributions in a pseudo-Voigt function corresponded only to strain from dislocations.  The kinetics of the dislocation density evolution to recrystallization were studied isothermally at 2 minute intervals, and isochronally at 175 and 205°C.  The data fit the Nes model, in which the interalloy region recovered faster than AA6XXX at 175°C, but was slower at 205°C.  This was most likely caused by change in texture and chemistry within this region such as over-aging of AA6XXX . Simulation of a continuous annealing and self homogenization process both with and without pre-recovery indicates a detectable, though small change in the texture and grain size in the interalloy region.

abstract: M.A.Sc.


title: Calculating and Limiting Local Strains in Geomembranes From Gravel Indentations

contributor:
Brachman, Richard W. I.
Civil Engineering

subject: Geomembrane Landfill

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-30 01:44:54.904

abstract:
Short-term tensile strains that arise from local gravel indentations in municipal solid waste landfill base geomembrane liners are investigated with an emphasis on quantifying how strains are obtained and providing methods for limiting long-term local geomembrane strains below allowable levels. This involved the development of new experimental techniques and apparatuses to study geomembrane strains under controlled conditions.
An experimental technique to measure the radial and vertical components of displacement from local gravel indentations in a geomembrane is presented. Geomembrane strains were calculated using large strain-displacement theory, thin shell theory, and the arc elongation method. While radial displacements were found to be small relative to vertical displacements, they were shown to provide the dominant contribution to the maximum strain beneath the centre of the gravel indentation. Both the thin shell and arc elongation methods produced incorrect distributions of strain and also provided magnitudes that significantly underestimated the maximum geomembrane strain.
Small-scale screening tests were conducted to gain insight into how key factors including the compressibility of the underlying clay layer, particle size of the overlying gravel, and mass of the geotextile protection layer influence local geomembrane strains. Results are provided that can be used to rule out protection layers that are unable to meet a long-term strain limit, and conversely, identify those that may be able to limit strains below a target strain for further larger scale evaluation. Compaction water contents towards the lower range of water content to achieve an acceptably low hydraulic conductivity of field compacted clay liners were found to be more successful in limiting local strains in the geomembrane. Protection from geotextiles with masses up to 2440 g/m2 were unable to limit geomembrane strains below 1.5% with nominal 50 mm gravel at a temperature of 55°C. Tests with nominal 25 mm gravel revealed that a geotextile with a mass of 1500 g/m2 successfully limited the maximum geomembrane strain below 1.5% at an applied stress of 250 kPa while another geotextile (2440 g/m2) met the strain limit up to applied stresses of 500 kPa at a temperature of 55°C.

abstract: M.A.Sc.


title: Planar Leaky-Wave Antennas and Microwave Circuits by Practical Surface Wave Launching

contributor:
Antar, Yahia M. M.
Freundorfer, Alois P.
Electrical and Computer Engineering

subject: 0756

subject: 0607

subject: 0544

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2013-09-30 08:29:04.107

abstract:
Modern communication systems have increased the need for creative antenna solutions and low-profile circuit configurations that can offer high-quality performance at a low cost. The microwave and millimeter-wave frequency ranges have shown much promise allowing for increased data transmission rates while also offering smaller and compact designs. Specific applications for these wireless systems include radar, biomedical sensors, phased arrays, and communication devices. Planar antennas and circuits are generally well adopted for these applications due to their low profile and ease of fabrication. However, classic feeding techniques for planar structures can be problematic. Losses can also be observed in these conventional feeding schemes due to unwanted surface wave (SW) excitation. This can lead to reduced antenna and circuit efficiencies, and thus, diminished system performance.

It is shown in this thesis that by the use of planar SW sources, or surface-wave launchers (SWLs), innovative and efficient antennas and feed systems are possible. Theoretical analysis and experimental verification for these SWLs are initially presented. New topologies and array configurations are also examined for directive beam steering at end-fire and at broadside. Additionally, studied structures include novel surface-wave antennas (SWAs) and leaky-wave antennas (LWAs) for 3-D beam pattern control in the far-field. A comprehensive design strategy is also examined which describes the implementation of these planar antennas using SWLs. This design strategy is based on a full-wave analysis of the modes that can be supported by the planar structures which include various planar-periodic metallic strip configurations and partially reflecting surfaces (PRSs) or screens. With appropriate conditions SWs can also be bound and guided for field channeling and power routing. For instance, novel planar metallic SW lenses and guidance structures are developed. Demonstrated applications include couplers, transition sections, as well as new planar circuits for power dividing/combining. To the author's knowledge, similar techniques have not been previously studied in the literature which allow for such controlled SW propagation and radiation. This way, SWs, which are normally considered an unwanted effect are used here to advantage.

abstract: As discussed with my supervisors, patents are pending and much of the work is under review for journal publications.

abstract: PhD


title: Laboratory and Modelling Study Evaluating Thermal Remediation of Tetrachloroethene and Multi-Component NAPL Impacted Soil

contributor:
Mumford, Kevin G.
Kueper, Bernard H.
Civil Engineering

subject:
Non Aqueous Phase Liquids
Multi-Component NAPL
Analytical Modeling
In situ Thermal Treatment

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-30 09:26:00.857

abstract: In Situ Thermal Treatment (ISTT) is a candidate remediation technology for dense non-aqueous phase liquids (DNAPLs). However, the relationships between gas production, gas flow, and contaminant mass removal during ISTT are not fully understood. A laboratory study was conducted to assess the degree of mass removal, as well as the gas generation rate and the composition of the gas phase as a function of different heating times and initial DNAPL saturations. The temperature of the contaminated soil was measured continuously using a thermocouple to identify periods of heating, co-boiling and boiling. Samples were collected from the aqueous and DNAPL phase of the condensate, as well as from the source soil, at different heating times, and analyzed by gas chromatography/mass spectrometry. In addition to laboratory experiments, a mathematical model was developed to predict the co-boiling temperature and transient composition of the gas phase during heating of a uniform source. Predictions for single-component sources matched the experiments well, with a co-boiling plateau at 88°C ± 1°C for experiments with tetrachloroethene (PCE) and water. A comparison of predicted and observed boiling behaviour showed a discrepancy at the end of the co-boiling period, with earlier temperature increases occurring in the experiments. The results of this study suggest that temperature observations related to the co-boiling period during ISTT applications may not provide a clear indication of complete NAPL mass removal, and that multi-compartment modeling associated with various NAPL saturation zones is required to consider mass-transfer limitations within the heated zone. Predictions for multi-component DNAPL, containing 1,2-Dichloroethane (1,2-DCA), PCE and Chlorobenzene, showed no co-boiling plateau. CB is the least volatile component and dominates in the vapour phase at the end of the co-boiling process, and it can be used as an indicator of the end of the co-boiling stage. Two field NAPL mixtures were simulated using the screening-level analytical model to demonstrate its potential application on ISTT. The two mixtures with similar composition but different mass fractions result in distinct co-boiling temperature and mass transfer behaviour. The non-volatile component in the NAPL mixture results in larger amounts of water consumption and longer ISTT operation time.

abstract: M.A.Sc.


title: Modelling Waves and Currents in Northeastern Lake Ontario to Assess the Impacts of a Proposed Offshore Wind Farm

contributor:
Boegman, Leon
Mulligan, Ryan P.
Civil Engineering

subject:
Wave and Hydrodynamic Modelling
Great Lakes Offshore Wind Farms

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-30 09:30:01.042

abstract: A spectral wave model (SWAN) coupled with a depth averaged hydrodynamic model (Delft3D) was used to understand the wave and flow dynamics of the Kingston Basin of Lake Ontario during large winter storm events. This model was then used to assess the impact of an offshore wind farm in the Kingston Basin. Results over different model domains with various forcing methods were compared to achieve the highest correlation with wave, current and water level observations from several locations. Storm events were modelled over the complex bathymetry of the basin and results were verified using wave and current profiler data collected during the winters of 2009-10 and 2011-12. Waves were composed of both locally generated wind sea and swell from the main basin of Lake Ontario, while flows throughout the Kingston Basin showed a complex circulation pattern. This circulation is composed of several wind-driven gyres, which are magnified during storm events. The impact of waves on the circulation patterns within the basin is highest in shallow areas where wave breaking drives circulation. To simulate a wind farm, a transmission coefficient was used in the wave model to represent the effects on waves, and an energy loss term was added to the hydrodynamic momentum equations to represent the added drag of the piles on the circulation. The results indicate that the coastal areas in eastern Lake Ontario will be minimally affected. The headlands of Big Sandy Bay, Wolfe Island, could see the largest coastal effects with changes in significant wave height predicted to be < 2%. The majority of impacts to circulation occur in the near-field, with changes in current magnitude of < 0.08 m s-1 (up to 50%). Areas near Wolfe Island exhibit changes of ~ 0.05 m s-1 (30 %), although overall circulation patterns throughout the basin are not affected. The majority of changes to surface waves and wind-driven currents are due to wind farm position with respect to wind direction and the re-direction of flows and waves as they pass through the wind farm.

abstract: M.A.Sc.


title: Hybrid Constitutionalism to Mainstream Human Rights in a Unified Korea

contributor:
Kahana, Tsvi
Law

subject:
Comparative Studies
Constitutionalism
Korean Constitutionalism
Constitution Building
Transition
Traditional Constitutionalism
Transitional Constitutionalism
Human Rights
Institutions
Good Governance
North Korea
Democratization
Korean Unification

abstract: Thesis (Master, Law) -- Queen's University, 2013-09-30 11:35:33.362

abstract: Amidst the global wave of democratization, modernization, and economic engagement during the 1980s and 1990s, the traditional tenets of constitutionalism have proven to be unwieldy dogma for States undergoing periods of rapid transition. In order to retain the administrative capacity to steer – rather than merely adapt to – political and social change, numerous transitioning States have adopted a new paradigm of constitutionalism, namely transitional constitutionalism, characterized by a centralized and streamlined structure of governance. However, in many instances, including Korea’s post-division transitional history, this model has demonstrably undermined fundamental human rights protections. In this thesis, I propose a hybrid constitutional paradigm for unification in Korea (another form of State transition) which seeks to balance the dual objectives of effective governance and human rights protection. I do so by examining and critiquing the core principles of traditional and transitional constitutionalism, outlining the human rights issues that the unified Korea will likely confront in its constitutional trajectory based on an analysis of Korea’s political, social, cultural, and constitutional history, and finally proposing a hybrid model of constitutionalism that utilizes an institutional approach to prevent violations of human rights in the unified Korea while allowing the State to retain governmental efficiency during transition.

abstract: LL.M.


title: Comparison of Two Loading Surface Preparation Methods on Rat Vertebral Bodies for Compression Testing

contributor:
Dumas, Geneviève A.
Pilkey, A. Keith
Mechanical and Materials Engineering

subject:
Compression Testing
Bone

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-09-30 11:58:32.794

abstract:
Osteoporosis is a disease characterized by bone loss affecting 10% of the US population over 50 years old.  The spine is one critical area affected by the disease.  The effectiveness of experimental treatments can be tested on an ovariectomized rat osteoporosis model.  As a result, lumbar vertebral bodies are often mechanically tested in uniaxial compression in order to determine whether or not the mechanical properties of the bone in ovariectomized rats improve with treatment.  The irregular shape of rat vertebral bodies requires some specimen preparation to create two parallel loading surfaces for uniaxial compression testing.
Two specimen preparation methods are reported in the current body of literature. One cuts the cranial and caudal surfaces to make them parallel to each other. The other cuts the caudal surface and uses bone cement to create a flat loading surface at the cranial end.  In this thesis a total of twenty rat vertebral bodies were tested. Ten were prepared with a cut specimen preparation method and ten with an embedding method.   Each specimen was tested in uniaxial compression and was microCT scanned before and after testing.  Eleven parameters were calculated from the mechanical testing data and compared between the two groups using Student’s t-tests.  The specimens were also categorized into six failure modes and locations observed in the microCT images.
The embedded specimens showed a lower stiffness (p = 0.026), greater yield displacement (p = 0.007) and apparent strain at failure (p = 0.050).  These differences were largely attributed to the embedded specimens being 1 mm taller than the cut specimens.  The shorter size of the cut specimens affected the mechanical parameters.  The cut specimens were easier to prepare and were less sensitive to end effect failures.  The embedded specimens kept the endplate, which distributes the load from the intervertebral disk through the vertebral body, intact.  In addition, the embedded specimens exhibited two failure modes, endplate failure and failure at the center of the vertebral body, observed in ex vivo human lumbar vertebral body testing, which suggests the interaction of the vertebral body with the endplate is an important factor in vertebral body failure in uniaxial compression testing.  In conclusion, neither preparation method showed an overwhelming advantage over the other, and experimental parameters should be considered when choosing a loading surface preparation method.

abstract: M.A.Sc.


title: A Modified Detector Concept for SuperCDMS: The HiZIP and Its Charge Performance

subject:
cryogenic detector
SuperCDMS
particle detector
dark matter
WIMP search

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-09-30 23:48:49.375

abstract:
SuperCDMS is a leading direct dark matter search experiment which uses solid state detectors (Ge crystals) at milliKelvin temperatures to look for nuclear recoils caused by dark matter interactions in the detector. ‘Weakly Interacting Massive Particles’ (WIMPs) are the most favoured dark matter candidate particles. SuperCDMS, like many other direct dark matter search experiments, primarily looks for WIMPs. The measurement of both the ionization and the lattice vibration (phonon) signals from an interaction in the detector allow it to discriminate against electron recoils which are the main source of background for WIMP detection.
SuperCDMS currently operates about 9 kgs worth of germanium detectors at the Soudan underground lab in northern Minnesota. In its next phase, SuperCDMS SNOLAB, it plans to use 100-200 kg of target mass (Ge) which would allow it to probe more of the interesting and unexplored parameter space for WIMPs predicted by theoretical models. The SuperCDMS Queen’s Test Facility is a detector testing facility which is intended to serve detector testing and detector research and development purposes for the SuperCDMS experiment.
A modified detector called the ‘HiZIP’ (Half-iZIP), which is reduced in complexity in comparison to the currently used iZIP (interleaved Z-sensitive Ionization and Phonon mediated) detectors, is studied in this thesis. The HiZIP detector design also serves to discriminate against background from multiple scatter events occurring close to the surfaces in a single detector. Studies carried out to compare the surface event leakage in the HiZIP detector using limited information from iZIP data taken at SuperCDMS test facility at UC Berkley produce a highly conservative upper limit of 5 out of 10,000 events at 90% confidence level. This upper limit is the best among many different HiZIP configurations that were investigated and is comparable to the upper limit calculated for an iZIP detector in the same way using the same data. A real HiZIP device operated at Queen’s Test Facility produced an exposure limited 90% upper limit of about 1 in 100 events for surface event leakage. The data used in these studies contain true nuclear recoil events from cosmogenic and ambient neutrons. This background was not subtracted in the calculation of the upper limits stated above and hence they are highly conservative.
A surface event source was produced by depositing lead-210 from radon exposure onto a copper plate. This source was then used to take data for a surface event discrimination study of the HiZIP detector operated at Queen’s Test Facility.
A study of the contribution of the noise from capacitive crosstalk between charge sensors in a HiZIP detector configuration was investigated, confirming the expectation that no significant drop in performance is to be expected due to this effect.

abstract: M.Sc.


title: From Clinical Trials to Clinical Practice: An International Survey of Oncologists on Health-Related Quality of Life Outcomes

contributor:
Brundage, Michael D.
Community Health and Epidemiology

subject:
Health-Related Quality of Life
Oncology
Clinical practice
Clinical trials

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2013-09-30 12:56:09.362

abstract:
Background: Health-related quality of life (HRQL) outcomes have been increasingly used in phase III randomized controlled trials to characterize the benefits or risks of a cancer treatment. HRQL outcomes from clinical trials can also inform clinical practice in oncology settings. Previous qualitative research suggests that oncologists value HRQL outcomes but challenges to their clinical application exist. Little quantitative research has been conducted to examine these barriers. This study describes the opinions of oncologists toward HRQL outcomes, the ways in which HRQL outcomes can be presented, and the importance of suggested reporting standards for HRQL outcomes in clinical trials. It further examines the association between attitudinal and demographic factors associated with the self-reported current use and achievable use of HRQL outcomes in clinical practice.
Methods: This study is a cross-sectional survey of oncologists. A web-based questionnaire was disseminated in Canada, United Kingdom, and Australia/New Zealand. The study included oncologist members of the NCIC Clinical Trials Group, the NCRI Clinical Studies Groups, and the Australasian Cancer Clinical Trials Groups.  Respondents were asked to report their opinions toward HRQL outcomes and the factors associated with the use of these outcomes in clinical practice. Demographic characteristics were also collected. Chi-square tests were used to compare the proportion of responses between countries. Logistic regression was used to identify factors associated with the use of HRQL outcomes in clinical practice.
Results: A total of 344 oncologists completed the survey. Most oncologists (65.9%) reported having a good knowledge of HRQL outcomes and 72% perceived HRQL outcomes to be useful. High current use of HRQL outcomes in clinical practice was associated with more medical practice experience; perceiving HRQL outcomes to be useful; perceiving HRQL measurements to be reliable; and reporting lack of understanding to rarely be a barrier to using HRQL outcomes. High achievable use of HRQL outcomes in clinical practice was associated with being a male oncologist, perceiving HRQL outcomes to be useful, and being an investigator in RCTs.
Conclusions: Important factors associated with the use of HRQL outcomes in clinical practice were identified, highlighting the need for future research and education.

abstract: Results of parent study not yet published.

abstract: M.Sc.