title: A Speech Enhancement System Based on Statistical and Acoustic-Phonetic Knowledge

contributor:
Gazor, Saeed
Electrical and Computer Engineering

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subject:
speech enhancement
noise reduction
acoustic-phonetics

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2009-08-24 21:32:48.966

abstract:
Noise reduction aims to improve the quality of noisy speech by suppressing the background noise in the signal. However, there is always a tradeoff between noise reduction and signal distortion--more noise reduction is always accompanied by more signal distortion. An evaluation of the intelligibility of speech processed by several noise reduction algorithms in [23] showed that most noise reduction algorithms were not successful in improving the intelligibility of noisy speech.

In this thesis, we aim to utilize acoustic-phonetic knowledge to enhance the intelligibility of noise-reduced speech. Acoustic-phonetics studies the characteristics of speech and the acoustic cues that are important for speech intelligibility. We considered the following questions: what is the noise reduction algorithm that we should use, what are the acoustic cues that should be targeted, and how to incorporate this information into the design of the noise reduction system.

A Bayesian noise reduction method similar to the one proposed by Ephraim and Malah in [16] is employed. We first evaluate the goodness-of-fit of several parametric PDF models to the empirical speech data. For classified speech, we find that the Rayleigh and Gamma. with a fixed shape parameter of 5, model the speech spectral amplitude equally well. The Gamma-MAP and Gamma-MMSE estimators are derived. The subjective and objective performances of these estimators are then compared.

We also propose to apply a class-based cue-enhancement, similar to those performed in [21]. The processing directly manipulates the acoustic cues known to be important for speech intelligibility. We assume that the system has the sound class information of the input speech. The scheme aims to enhance the interclass and intraclass distinction of speech sounds. The intelligibility of speech processed by the proposed system is then compared to the intelligibility of speech processed by the Rayleigh-MMSE estimator [16]

The intelligibility evaluation shows that the proposed scheme enhances the detection of plosive and fricative sounds. However, it does not help in the intraclass discrimination of plosive sounds, and more tests need to be done to evaluate whether intraclass discrimination of fricatives is improved. The proposed scheme deteriorates the detection of nasal and affricate sounds.

abstract: M.Sc.


title: Low-Noise Mixing Circuits in CMOS Microwave Integrated Circuits

contributor:
Saavedra, Carlos E.
Electrical and Computer Engineering

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

subject: Electrical Engineering

subject: Monolithic Microwave Integrated Circuits

subject: CMOS

subject: RF

subject: Microwave

subject: MMIC

subject: Low-Noise Mixers

subject: Active Mixers

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2009-08-23 12:41:20.445

abstract:
In this thesis, three low-noise active mixing circuits are presented in CMOS technology. Mixers can be found at the front-end of almost every communication systems. However, despite many advantages the active mixers have, one drawback is their poor noise performance. One mixer that has been widely used in integrated circuit is the Gilbert cell. This thesis demonstrated that by merging the low-noise amplifier (LNA) with the Gilbert cell, a low-noise active mixer can be realized. This kind of mixer relaxes the front-end design, allows higher circuit integration, and reduces power consumption.

The first circuit is a narrowband low-noise mixer that operates at 5.4 GHz in 0.18 um CMOS. An inductive degenerated LNA is used as the transconductor. Together with a current bleeding circuit, a gain of 13.1 dB and a low 7.8 dB single-sideband noise figure are achieved. The circuit was fabricated and measured. Simulation and measurement results are compared and discussed.

The second circuit is a broadband low-noise mixer that operates between 1 and 5.5 GHz in 0.13 um CMOS. The noise-cancelling technique is used to design the transconductors. This technique does not require the use of inductors while able to achieve a sub 3 dB noise figure and input matching over a large bandwidth. To further extend the mixer bandwidth, the series inductive peaking was used. Measured and simulated results showed great agreement. It has a high gain of 17.5 dB, a bandwidth of 4.5 GHz, and a low average double-sideband noise figure of 3.9 dB. This mixer has the best broadband noise performance ever reported in CMOS.

Finally, a double-balanced low-noise self-oscillating mixer (SOM) in 0.13 um CMOS is presented. This is a current-reuse, highly integrated circuit that combines an LNA, mixer, and oscillator seamlessly into a single component. The oscillator generates the required LO while serving as the mixer load simultaneously. Measured and simulated results showed excellent agreement. A low double-sideband noise figure of 4.4 dB and a gain of 11.6 dB were measured. This type of SOM and loading structure are the first ever reported.

abstract: M.Sc.


title: Tissue-specific transcriptional regulation of monocarboxylate transporters (MCTs) during short-term hypoxia in zebrafish (Danio rerio)

contributor:
Wang, Yuxiang S.
Biology

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subject: hypoxia, zebrafish, MCT

abstract: Thesis (Master, Biology) -- Queen's University, 2009-08-24 13:44:06.114

abstract:
Monocarboxylate transporters (MCTs) have been shown to be important in regulating metabolism during hypoxia in mammals.  However, the role of MCTs in hypoxic survival in lower vertebrates is currently unclear.  The goal of this study was to investigate the coordination of MCTs along with other metabolic proteins during hypoxia.  Therefore, we subjected zebrafish (Danio rerio) to 1.5 mg L-1 O2 over 48 and 96-hr and measured tissue-specific transcriptional changes of MCTs (1, 2 and 4), lactate dehydrogenase A (LDHa), citrate synthase (CS), and other metabolic proteins using real-time RT-PCR.  There were no changes in mRNA in muscle at 48 and 96-hr.
When data from both time points were pooled in brain, a significant increase was found in MCT4 (+102%) and LDHa (+28%) mRNA indicating a preference towards glycolysis.  In gills, there were increases in LDHa at 48-hr (+101%) and MCT1 (+24%) mRNA from pooled data suggesting that both anaerobic and aerobic metabolism is being utilized.  Heart had the greatest changes in transcriptional levels compared to other tissues. At 48-hr, increases were found in MCT1 (+117%), MCT4 (+86%), LDHa (+197%), and pooled data showed an increase in CS (+18%) mRNA.  These results indicate that the influx and efflux of lactate are both employed as strategies in cardiac tissue during hypoxia.  This study has shown that fish utilize tissue-specific regulation of MCTs along with other metabolic genes during hypoxia.

abstract: M.Sc.


title: Effects of Acute Stress on Motor and Cognitive Impulsivity

contributor:
Olmstead, Mary C.
Psychology

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subject:
addiction
stress
impulsivity
animal model

abstract: Thesis (Master, Psychology) -- Queen's University, 2009-08-24 15:17:00.597

abstract: Impulsivity and stress are two of the most important determinants of drug addiction in that both factors predict the initiation and maintenance of drug use, as well as relapse to drug taking following abstinence. Despite this combined influence, the interaction between stress and impulsivity has never been examined systematically in animal models of addiction. The objective of the current study is to examine the role of acute stress on two different measures of impulsivity in rats: the Go/No-go test measures motor impulsivity, and the Delayed Reinforcement Paradigm measures cognitive impulsivity.  To determine whether a 1 hr restraint stress is physiologically stressful, blood samples from rats in Experiment 1 were taken at 5 different sampling points: baseline (0 min), reactivity (15 and 60 min) and recovery (100 and 180 min). In Experiments 2 and 3, rats were tested in either the Go/No-go test or the Delayed Reinforcement test immediately following 1 hr of restraint stress. Results from Experiment 1 show that 1 hr of restraint stress increased plasma corticosterone concentrations at 15 min and 60 min; corticosterone concentrations returned to baseline levels by 100 min. Following stress, the percentage of Go interval responding was not altered during Go/No-go testing (Experiment 2), nor were there changes in the indifference point values during Delayed Reinforcement testing (Experiment 3). These results suggest that 1 hr of acute stress does not increase either motor or cognitive impulsivity, and stress may influence addiction via mechanisms that are independent of impulsivity.

abstract: M.Sc.


title: Error-Resilient Tile Sets for DNA Self-Assembly

contributor:
Kashyap, Navin
Mathematics and Statistics

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subject:
DNA Self-Assembly
Tile Sets
DNA Computing
Error Resilient n-way Overlay Tile Sets
Malformed Tile Sets
Modified Snaked Proofreading Tile Sets

abstract: Thesis (Master, Mathematics & Statistics) -- Queen's University, 2009-08-25 11:10:39.142

abstract:
Experiments have demonstrated that DNA molecules can compute like a machine to
solve mathematical problems, which is significant because of their parallel computation ability. However, due to the nature of biochemical reactions, DNA computation suffers from errors, which are its main limitation. The abstract and kinetic Tile Assembly Models are now commonly used to simulate real DNA computing experiments, and to look for new methods to advance the accuracy of DNA-based computation. One means of controlling errors is through proofreading tile sets. Several such tile sets have been proposed in the literature, such as Chen and Goel’s snaked proofreading tile sets, the 2-way and 3-way overlay tile sets of Reif et al., and Rothemund and Cook’s n-way overlay tile sets.

In the first part of this thesis, we analyze the performance of the Rothemund-Cook
n-way overlay tile sets. We prove that the n-way overlay tile set contains n^2+3n+4
rule tiles. Simulation results show that these tile sets clearly perform better than
tile sets without any error-control mechanism, and the performance improves as n
increases. It is also proved that the error rates in assemblies formed by the 1-way and
2-way tile sets are O(epsilon^2), where epsilon is the error rate in assemblies without any error correction.

In the second part of this thesis, we focus on a different error mechanism, namely,errors caused by imperfect or malformed tiles. We propose a model of malformed tiles, and consider the performance of various proofreading tile sets in the presence of malformed tiles. Our simulation results show that the Reif et al. 3-way overlay tile sets are able to best deal with malformed tiles. During the simulations, we observed that snaked proofreading tile sets always have trouble completing whole patterns when malformed tiles are present. We instead propose two modified snaked proofreading constructions, and verify through both simulations and analysis that the two modified constructions have much better performances.

abstract: M.Sc.


title: Incorporating Environmental Impacts into Multi-Objective Optimization of Water Distribution Systems

contributor:
Filion, Yves R.
Hall, Kevin
Civil Engineering

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subject:
Engineering
Sustainability
Water Distribution System
Optimization
Environmental Impact

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2009-08-25 16:08:33.636

abstract:
Municipal water distribution system (WDS) expansion is often focused on increasing system capacity with designs that best meet hydraulic requirements at the least cost.  Increasing public awareness regarding global warming and environmental degradation is making environmental impact an important factor in decision-making for municipalities.  There is thus a growing need to consider environmental impacts alongside cost and hydraulic requirements in the expansion and design of WDSs.  As a result, the multiplicity of environmental impacts to consider in WDS expansion can complicate the decisions faced by water utilities.  For example, a water utility may wish to consider environmental policy issues such as greenhouse gas emissions, non-renewable resource use, and releases to land, water, and air in WDS expansion planning.

This thesis outlines a multi-objective optimization approach for WDS design and expansion that balances the objectives of capital cost, annual pumping energy use, and environmental impact minimization, while meeting hydraulic constraints.  An environmental impact index that aggregates multiple environmental measures was incorporated as an environmental impact objective function in the multi-objective non-dominated sorting genetic algorithm-II (NSGA-II) optimization algorithm.  The environmental impact index was developed to reflect stakeholder prioritization of specific environmental policy issues.  The evaluation of the environmental impact index and its application to the WDS expansion problem was demonstrated with a water transmission system example.  The environmental impact index and multi-objective non-dominated sorting genetic algorithm-II (NSGA-II) optimization algorithm were applied to the “Anytown” network expansion problem.  Preliminary results suggest that solutions obtained with the triple-objective capital cost/energy/EI index optimization minimize a number of environmental impact measures while producing results that are comparable in pumping energy use and, in some instances, slightly higher in capital cost when compared to solutions obtained with a double cost/energy optimization in which environmental impact was not considered.

abstract: M.Sc.


title: The Stellar Populations and Evolution of Virgo Cluster Galaxies

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subject:
Extragalactic Astronomy
Galaxy Evolution
Stellar Content
Star Formation Histories
Chemical Evolution
Galaxy Clusters

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-08-25 14:12:46.48

abstract:
Using a combination of optical and near-infrared photometry, we have studied both the resolved and integrated stellar populations for a sample of Virgo cluster galaxies spanning the full range of galaxian parameters. The derived stellar population properties are compared against galaxy structural and environmental measures to gauge the importance of these factors in establishing galaxy star formation histories and chemical evolution.
Although galaxy colours do not uniquely probe a galaxy's star formation history, meaningful results may be obtained if considered in a relative sense. We find that colour profiles reflect variations in both stellar age and metallicity within galaxies. We also uncover systematic variations in colour gradients, and thus age/metallicity gradients, along the Hubble sequence, such that age and metallicity gradients become increasingly negative toward later Hubble types. However, only weak correlations exist between galaxies' stellar populations and their structure and environment. The correlations we find suggest that the star formation histories of gas-rich galaxies are strongly influenced by gas removal within the cluster, while their chemical evolution is due to a combination of stellar mass-dependent enrichment and outflow retention.
The assembly of gas-poor giant galaxies is consistent with a hierarchical scenario wherein gas-rich mergers dominate by number. Gas-poor dwarfs differ from the giants, however, appearing as the product of environmentally-driven evolution. Spiral galaxies bridge the dwarf-giant gap, whereby merging and gas-stripping signatures are imprinted in their stars. Early-type spirals seem to have fallen into the cluster sooner than the later types, thereby ceasing star formation in their disks at earlier epochs. The bulges of both types, however, appear to have grown via merging. The nature of this merging (minor versus major) remains unknown. Irregular galaxies exhibit signs of a recent gravitational encounter that has redistributed both their stars and gas, the latter of which caused recent star formation.

abstract: M.Sc.


title: Knee Joint Biomechanics in People with Medial Compartment Knee Osteoarthritis

contributor:
Culham, Elsie
Rehabilitation Science

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subject:
knee osteoarthritis
knee flexion moment
knee extension moment
knee adduction moment

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2009-08-27 00:37:29.466

abstract: Background: Sagittal plane external flexion moment in early stance has been reported to be both higher and lower in people with medial knee OA compared to control subjects. Purpose: Sagittal plane knee joint kinetics and kinematics were compared between people with medial compartment OA and healthy subjects. Subjects with OA and low pain scores were also compared to those with OA and moderate pain scores. Subjects: Forty people with medial knee OA and 40 age and sex matched control subjects. Method: Knee alignment and OA severity were measured from radiographs. Frontal and sagittal plane moments and knee flexion angle during gait were measured using a three dimensional motion analysis system and force plates. The Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) was used to measure pain; this score was used to divide the OA group into low pain and moderate pain OA groups. The relationship between knee flexion moment in early stance and gait speed, knee flexion angle and pain was also determined. Results: Subjects with OA had lower gait speed and cadence, and higher double limb support time. Peak knee adduction moment (first 50% of the gait cycle) was higher in the OA group. The knee flexion moment in early stance did not differ between groups; however the knee extension moment in late stance was lower in the knee OA group. The moderate pain group walked more slowly than the low pain group. The knee adduction moment, sagittal plane moments and knee flexion angle in stance did not differ between OA groups. A positive correlation was found between knee flexion moment and knee flexion angle in early stance in the knee OA group; the correlations between knee flexion moment and pain and gait speed were not significant. Conclusion: No differences were found in the knee flexion moment or stance phase knee flexion angle between the groups compared in this study, and therefore the results do not contribute to resolution of the controversy in the literature. Participants with knee OA in this study had relatively mild to moderate disease severity, which may have contributed to the non-significant findings.

abstract: M.Sc.


title: Biomechanics and Metabolic Costs of Overground and Treadmill Walking in Healthy Adults and in Stroke Subjects

contributor:
Brouwer, Brenda
Olney, Sandra
Rehabilitation Science

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subject:
Overground Gait
Treadmill Gait
Biomechanics
Metabolic Costs
Stroke

abstract: Thesis (Ph.D, Rehabilitation Science) -- Queen's University, 2009-08-27 06:41:19.999

abstract: Background:	Though numerous studies have compared overground and treadmill walking there still exists a significant debate about whether the two modes of walking are equivalent. The present study provides a comprehensive evaluation of overground and treadmill walking at matched speeds and increasing treadmill speeds. Walking performance was compared in healthy adults, in people with stroke and between the groups. This is important to know because any differences may have implications for gait training in both groups. Methods: Ten healthy adults (50-73 years) and ten subjects with stroke (54-80 years) walked at their self-selected speed overground which was matched on a treadmill. Temporal parameters, angular kinematics and vertical ground reaction forces were recorded during walking once subjects were in steady state as determined from their heart rate and oxygen uptake, both of which were also recorded. Belt speed was then increased 10% and 20% above matched speed and steady state recordings obtained. Speed related adjustments were also evaluated and compared between the two groups of subjects.  Results: For healthy adults, step, stride, and joint angular kinematics were similar for both modes of walking. Small reductions in double support time and decreased push-off force were evident on the treadmill. For subjects with stroke, step, stride, and stance times were longer when walking overground but the degree of symmetry was comparable for both surfaces. Kinematic data revealed interlimb asymmetry was more pronounced for all lower limb joint excursions during overground walking and vertical forces were higher. In comparison to healthy adults, stroke subjects walked with lower cadence, shorter strides, lower stance time, and smaller lower limb joint excursions than their healthy counterparts. When compared with overground walking the metabolic requirements of treadmill walking for healthy adults and subjects with stroke however were about higher by 23% and 15% respectively. All temporal-distance parameters, hip joint excursion, F1 and F2 forces and metabolic costs showed main effects of speed. An interaction between speed and group indicated that oxygen consumption increased at a greater rate in stroke than healthy subjects. Conclusions: The findings suggest that, although overground and treadmill gait patterns are similar for each group of subjects, people with stroke adopt a more symmetrical kinematic walking pattern on the treadmill that is maintained at faster belt speeds. Although there are differences in gait patterns between healthy and stroke subjects, both groups respond to the challenge of increased walking speed in the same way. One important difference is the abnormal elevation of energy demands associated with treadmill walking at faster speeds in stroke. Clinically, this warrants consideration as it may lead to premature fatigue and undesirable cardiorespiratory challenge in this group of individuals.

abstract: PhD


title: Laser Doppler Imaging: a New Measure of Genital Blood Flow in Female Sexual Arousal

contributor:
Pukall, Caroline F.
Psychology

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subject:
Sexual Arousal
LDI

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-08-27 10:09:26.355

abstract: Female sexual arousal refers to one’s feelings of sexual excitement and pleasure and has both physiological (i.e., objective) and psychological (i.e., subjective) components. It is an important, yet difficult phenomenon to investigate. As a result, many instruments have been used in an attempt to accurately measure female arousal; however, there are problems associated with each. Furthermore, the relationship between the subjective and physiological indicators of sexual arousal appears to be influenced by the instrument used to measure physiological sexual arousal. Specifically, instruments measuring physiological arousal internally (i.e., vaginal photoplethysmography) typically yield lower correlations between measures of physiological and subjective sexual arousal than instruments examining the external genitals (i.e., labial thermistor, thermal imager), which indirectly measure blood flow. Alternatively, laser Doppler imaging (LDI) is a direct measure of external genital blood flow but has only been used in one previous study that did not assess the relationship between physiological and subjective sexual arousal. The aims of the current study were to investigate the usefulness of LDI for assessing genital blood flow in women in response to erotic visual stimuli, and to explore the relationship between physiological and subjective indicators of sexual arousal. In addition, the role of psychosocial variables in predicting physiological and subjective sexual arousal was also examined. Eighty sexually healthy women completed a psychosocial interview and questionnaires. Participants also watched three 15-minute films during LDI scanning: two nature films (measuring acclimatization and baseline blood flow levels) and one randomly assigned experimental film (erotic, anxiety, humor, or neutral). They were asked to rate their level of subjective sexual arousal throughout and following the third film. Results indicated that LDI was able to differentiate the erotic condition from the three non-erotic conditions, and that physiological and subjective sexual arousal were significantly correlated. Although the psychosocial variables did not significantly predict either component of sexual arousal, specific variables moderated the association. Psychological, sexual, and social variables, along with genital sensations, played significant roles in the relationship between subjective and physiological sexual arousal. These findings suggest that LDI is a useful instrument for measuring female sexual arousal, and that sexual arousal is a complex process that requires further empirical investigation.

abstract: PhD


title: Setting the Sites High: Measuring Viewer Attention to and Recall of Framed Osteoporosis Prevention Print  Advertisements

contributor:
Latimer, Amy
Kinesiology and Health Studies

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subject:
Eye Tracking Technology
Elaboration Likelihood Model
Message Framing
Osteoporosis Prevention
Attention
Cognitive Processing

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-08-27 16:13:32.848

abstract: Building on Message Framing Theory and the Elaboration Likelihood Model (ELM), this study examined how message frame impacts viewer attention to and cognitive processing of osteoporosis prevention print ads. Attention was measured with eye tracking technology, which calculated participants’ number of fixations and dwell time. Cognitive processing was assessed through a textual masked-recall exercise. Sixty women, with a mean age of 21.25+/-2.61 years, viewed the same 36 ads; however, the message frame changed on a randomized, rotating basis, resulting in each group viewing 12 gain-, 12 loss-, and 12 neutrally-framed ads. One-way repeated measures analyses of variance revealed that message frame significantly impacted viewers’ number of fixations, F(2,118)=8.18, p<.01, η2= .12 dwell time, F(2,118)=9.84, p<.01, η2= .14 and  masked-recall results, F(2,118)=22.28, p<.01, η2 = .27. Viewers’ number of fixations, dwell time and recall of gain-framed osteoporosis prevention ads was significantly higher than to loss- or neutrally-framed ads, p<.01. Message frame was also positively correlated with number of fixations, r=.29, p<.02 and dwell time, r=.42, p<.01. Findings may help expand theory related to message framing and the ELM, while contributing to advancements in eye tracking literature and health communications practice.

abstract: M.Sc.


title: Cellular signalling pathways involved in thermoprotection of neural ciruit function in the locust.

contributor:
Robertson, Mel
Biology

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subject: Neurobiology Neurophysiology

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2009-08-27 16:11:09.581

abstract:
Environmental temperature is arguably one of the most important abiotic physical factors
affecting insect behaviour. Temperature affects virtually all physiological processes
including those that regulate nervous system function. It is therefore not surprising that
animals have evolved adaptations that confer tolerance to heat stress and allow for
continued behaviour as ambient temperature fluctuates. Most animals have central
nervous system (CNS) responses to heat shock (HS) preconditioning which extend the
thermal operating range of neural circuits during exposure to extreme heat. It is unclear how HS preconditioning confers CNS thermotolerance. I used the migratory locust
(Locusta migratoria), an animal that inhabits environments that can have large
fluctuations in ambient temperature daily, to examine how neuronal circuits cope with
temperatures stress. Using the ventilatory central pattern generator (vCPG) as a model
circuit I was able to address how the CNS switches on adaptations which provide
protection against heat stress. vCPG thermotolerance was manifested as an increase in the thermal operating range and a decrease in the length of time required to recover vCPG activity when temperature stress was removed. I investigated the octopaminergic (OA/cAMP/PKA) and nitrergic (NO/cGMP/PKG) signalling pathways and tested their involvement in conferring thermotolerance to the vCPG during heat stress. I found that long applications of octopamine, or increased adenylate cyclase activity generated vCPG thermotolerance and was dependent upon transcription and translation. In addition I found that HS-treated locust had significantly reduced nitric oxide (NO) production during heat stress, and when I pharmacologically reduced PKG activity vCPG thermotolerance was generated. However, unlike octopamine treatment thermotolerance could be observed within minutes following PKG inhibition. Thus I conclude that the octopaminergic and nitrergic pathways coordinate long- and short-term protective modulation of the locust CNS.

abstract: PhD


title: Investigations of Backfill - Rock Mass Interface Failure Mechanisms

contributor:
De Souza, Euler
Mining Engineering

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subject: mining backfill pastefill roughness friction strength

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2009-08-27 16:07:21.916

abstract:
From previous research, it has been proven that rock roughness and closure are two important factors for stability of backfilled stope and exposed backfill.

In order to estimate the important parameters of roughness, several investigations have been conducted in other scientific fields to study roughness. The results showed that the important roughness parameters are application-dependent.

In geology and rock mechanics the Joint Roughness Coefficient (JRC) is a critical factor that incorporates the roughness in stability problems. Although JRC is widely used, it is very subjective and highly depends on the experience of the individual conducting the analysis. During the last several decades there were attempts to use different methods such as fractal geometry, Fourier analysis, analytical methods, etc. to convert a random surface profile into a JRC.

The goal of the current research is to estimate with greater accuracy the contribution of roughness to the shear strength of the interface at the paste-rock contact when backfilling. Four hundred and fifty backfill samples were constructed and tested in a shear box. The variables of the tests are three: binder percentage, roughness and cure time. From the test results the importance of each of those parameters to the final shear strength of the paste-rock interface was estimated. The normal stress that acts on the samples is also a critical factor. From the tests that were tried, it was concluded that there are limits in normal stress for which roughness is important.

abstract: M.A.Sc.


title: Sequence Diagrams Integration via Typed Graphs: Theory and Implementation

contributor:
Dingel, Juergen
Computing

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subject:
model driven
model transformation
model integration
source transformation
category theory

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2009-08-28 13:03:08.607

abstract:
It is widely accepted within the software engineering community that the support
for integration is necessary for requirement models. Several methodologies, such as
the role-based software development, that have appeared in the literature are relying
on some kind of integration. However, current integration techniques and their tools
support are insufficient. In this research, we discuss our solution to the problem.
More precisely, we present a general integration approach for scenario-based models, particularly for UML Sequence Diagrams, based on the colimit construction known from category theory.

In our approach, Sequence Diagrams are represented by SD-graphs, a special kind
of typed graphs. The merge algorithm for SD-graphs is an extension of existing merge
operations on sets and graphs. On the one hand, the merge algorithm ensures traceability and guarantees key theoretical properties (e.g., “everything is represented and nothing extra is acquired” during the merge). On the other hand, our formalization
of Sequence Diagrams as SD-graphs retains the graphical nature of Sequence Diagrams,
yet is amenable to algebraic manipulations. Another important property of our process is that our approach is applicable to other kinds of models as long as they can be represented by typed graphs.

A prototype Sequence Diagram integration tool following the approach has been implemented. The tool is not only a fully functional integration tool, but also served
as a test bed for our theory and provided feedback for our theoretical framework. To
support the discovery and specification of model relationships, we also present a list
of high-level merge patterns in this dissertation.

We believe our theory and tool are beneficial to both academia and industry, as the initial evaluation has shown that the ideas presented in this dissertation represent promising steps towards the more rigorous management of requirement models.

We also present an approach connecting model transformation with source transformation
and allowing an existing source transformation language (TXL) to be used
for model transformation. Our approach leverages grammar generators to ease the
task of creating model transformations and inherits many of the strengths of the
underlying transformation language (e.g., efficiency and maturity).

abstract: PhD


title: Sensory Processing Patterns in High-Ability Adults with Autism Spectrum Disorders in the Workplace

contributor:
Lysaght, Rosemary
Rehabilitation Science

subject:
Sensory Processing
Autism Spectrum Disorder
Adults
Work
Employment
Mixed Methods

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2009-08-28 14:26:16.084

abstract:
Rationale: Previous studies have reported low employment rates for adults with autism spectrum disorders (ASD). The challenges to finding and maintaining work have been attributed to their social, communication, behavioural and sensory processing difficulties. Numerous studies report that children with ASD experience abnormal responses to sensory stimuli, whereas estimates for adults remain unclear. Furthermore, little is known about how sensory processing patterns affect employment.

Objectives: The purposes of this study were a) to describe the self-reported sensory processing patterns in high-ability adults with ASD and compare them to adults without ASD; and b) to explore the role that sensory processing patterns play in the workplace for high-ability adults with ASD.

Methods: A sequential mixed methods approach was used. In Phase I, 20 participants with and 20 without ASD completed the Adolescent/Adult Sensory Profile (AASP) and employment details. In Phase II, 10 of the 20 participants with ASD described their work experiences during phone interviews. Participants with ASD were recruited from autism societies in Ontario and Québec.

Results: Significant differences were found in all four subscales of the AASP between the high-ability adults with ASD and those without ASD. The adults with ASD obtained significantly higher scores on the Low Registration, Sensation Avoiding and Sensory Sensitivity subscales than the comparison group, and significantly lower scores on Sensation Seeking. Approximately half of the adults with ASD were employed, but few were experiencing sustained employment. Participants described using avoidant, replacement and preventative coping strategies to overcome overwhelming sensations at work. Enhanced sensory processing had the potential to improve work performance. Participants chose alternative work environments based on their sensory preferences and challenges. Disclosing their ASD diagnosis proved to be a delicate process, resulting in differential consequences on accommodations and workplace relationships.

Conclusions: High-ability adults with ASD displayed different sensory processing patterns compared to individuals without ASD. Most of these adults showed an awareness of their sensory needs. Sensory processing patterns impacted on work choice, performance and satisfaction. Accommodations that modified the physical environment and occupational tasks promoted an optimal work fit for individuals with sensory issues. Self-employment offered a means of self-accommodation.

abstract: I will be working on publications to journals that may require this restriction.

abstract: M.Sc.


title: Causal Uncertainty and Self-Regulation Abilities

contributor:
Jacobson, Jill A.
Psychology

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subject:
Causal Uncertainty
Self-Regulation

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-08-28 14:40:08.139

abstract:
Causal uncertainty refers to the lack of confidence in one’s ability to understand causal relations in the social world (Weary & Edwards, 1994). Relative to people with low causal uncertainty, individuals with high causal uncertainty exhibit enhanced self-regulation performance following a social interaction (Jacobson, Papile, Passey, & Boucher, 2006). The current studies investigated the potential mechanisms underlying this relationship, and the role of self-esteem.
Study 1 investigated whether the social or nonsocial nature of the depleting task and expectations about the need for future self-control could account for the relationship between causal uncertainty and self-regulation (N = 181). For the social task, high causally uncertain participants’ self-regulation performance was consistent across expectations for future self-control regardless of participant self-esteem. In contrast, low causally uncertain participants’ performance improved with increasing instructions to conserve energy for future tasks but only for participants with lower self-esteem. For low causally uncertain participants with higher self-esteem, self-regulation performance decreased with increased expectations for future self-control.
In the nonsocial condition, the findings did not differ by self-esteem. Learning that the future task involved self-control and that the initial task was depleting were both associated with increases in self-regulation for high causally uncertain participants. In contrast, self-regulation abilities did not differ for low causally uncertain participants upon learning that the future task involved self-control and marginally decreased when they learned that the initial task was depleting.
Study 2 examined whether or not self-presentation could account for the relationship between causal uncertainty and self-regulation abilities (N = 88). Higher causal uncertainty was associated with better self-regulation performance, but self-presentation goals did not moderate this relationship. Self-esteem did not influence self-regulation performance in this study.
Study 3 investigated whether or not an accuracy goal could account for the relationship between causal uncertainty and self-regulation abilities (N = 112). For participants with lower self-esteem, high causally uncertain participants’ self-regulation performance was consistent regardless of the goal manipulation; whereas low causally uncertain participants’ performance improved with instructions to create accurate impressions of their partner. In contrast, for participants with higher self-esteem, self-regulation did not differ by causal uncertainty or goal conditions.

abstract: PhD


title: Use of Dynamic Phase Angle and Complex Modulus for The Low Temperature Performance Grading of Asphalt Cements

contributor:
Hesp, Simon
Chemistry

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subject: Dynamic Shear Rheometer, Phase Angle

abstract: Thesis (Master, Chemistry) -- Queen's University, 2009-08-28 15:12:29.845

abstract:
This thesis discusses and documents the validation efforts related to Ontario’s LS-299 and LS-308 test methods which are two new test methods developed for the performance-based specification grading of asphalt cement. In addition, this report presents the field validation of a simple performance indicator, loss tangent, for specification grading of asphalt cement for thermal cracking. Furthermore, another objective of this study is to investigate and compare the low temperature fracture and rheological behavior of engineered asphalt materials from field and laboratory-aged test sections on Highway 655 in northern Ontario.
Extracted asphalt cements from 20 contract sites in eastern and northeastern Ontario were tested according to Ontario’s LS-299 and LS-308 test methods. It was found that all good performing contracts that showed little or no distress showed low grade losses in LS-308 and retained high strain tolerances as measured in LS-299 compared to the poor performing contracts.
Asphalt cements recovered from these 20 contract sites in eastern and northeastern Ontario were also tested in torsion bar geometry to determine their viscoelastic properties. It was decided to focus on the phase angle, as a more direct measure for low temperature performance. Phase angle is a very sensitive parameter to small changes in rheology as the phase angle is approximately equal to the derivative of the logarithm of the stiffness with respect to frequency.
It was found that tan() was able to distinguish good from poor performers with 95% accuracy after only a short period of conditioning prior to testing. This is a considerable improvement over the current low temperature bending beam rheometer protocol.
Black space diagrams, frequency sweeps, Cole-Cole plots, and master curves were generated for comparison of field and laboratory aged materials from the Highway 655 trial in northern Ontario. The findings show that chemical hardening occurs much faster in the field than through laboratory ageing methods. Also, reversible ageing of binders may occur at low temperatures and could be linked to field performance. Furthermore, a high low temperature phase angle appears to be a reasonable indicator for thermal cracking resistance.

abstract: M.Sc.


title: The Social Status and Thought of Merchants in Ming China, 1368-1644: a Foray in Clarifying the Social Effects of the Commercialization of Ming China

contributor:
Hill, Emily M.
History

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subject:
China, History
Ming Dynasty, 1368-1644

abstract: Thesis (Master, History) -- Queen's University, 2009-08-29 11:46:59.242

abstract: Recent proponents of non-Eurocentric approaches to the study of development in non-Western areas in the early modern period have seized on late imperial China (1368-1911) as an example of an indigenous trajectory of development that disputes the primacy of early modern Europe in some theories. The commercialization of Ming China (1368-1644) is sometimes appropriated in their arguments. But at times the term “commercialization” is not particularly well-defined in the case of sixteenth and seventeenth century China. In order to strengthen the arguments against Eurocentric assessments of non-Western development, this thesis covers some aspects of Ming commerce and society that are sometimes not captured by the term commercialization. In particular, it focuses on more ‘personal’ dimensions often neglected by references to the commercialization of China’s economy and society in the latter half of the Ming period. Aspects that will be discussed include: social change and social mobility, higher-ranking officials’ views of commerce and merchants, and the identity of merchants as seen in merchant manuals. The application of some recent research by other scholars of Ming China and my readings of some sources dating from the period, I hope, will add nuances to our understanding of Ming commerce and society and furthermore contribute to a detailed approach to the non-Eurocentric writing of a comparative history of development in the early modern world.

abstract: M.A.


title: Chronic Pain: a Community-Based Exercise and Education Program

contributor:
King-VanVlack, Cheryl
Rehabilitation Science

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subject:
Chronic Pain
Community-Based
Exercise
Education
Self-Management

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2009-09-14 13:01:08.784

abstract: Chronic pain affects approximately 16% to 36% of Canadian adults and is one of the most common reasons for physician visits in Canada. The effects of a self-referral community-based education/exercise program (Y-PEP) on physical function and well-being were initially evaluated in 20 individuals with chronic pain who had attended one of three Y-PEP sessions in 2007. The 10-week program incorporated chronic pain education/self-management and various exercise modalities to allow individuals with chronic pain to try different physical activities in a safe and supported environment. Questionnaires were administered pre-, post-program, and at 10-weeks follow-up and provided data on demographic information, physical activity levels, depression, pain perception, and pain catastrophizing. Maximal activity levels and adjusted activity levels increased 7% and 10% respectively at post-program, but only the adjusted activity levels remained elevated at the 10-week follow-up.  No significant changes occurred in any of the other outcome measures, however, the extent to which maximal and daily activity increased was significantly correlated with greater improvements in the extent to which pain interfered with one’s life (r=0.45) and with pain catastrophizing (r=0.45).  These latter two improvements were significantly associated with greater decreases in depression score (r=0.50). Overall, these findings suggest that a community-based program for individuals with chronic pain can improve physical function and psycho-social well-being. Further effort is required to establish such programs in communities for individuals with chronic pain.

abstract: M.Sc.


title: Using Small Molecules to Inhibit an E2A-PBX1:CBP Interaction Involved in Acute Lymphoblastic Leukemia

contributor:
Smith, Steven P.
LeBrun, David P.
Pathology and Molecular Medicine

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subject:
Leukemia
Small Molecules
Fluorescence Anisotropy
Protein-Protein Interaction

abstract: Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2009-08-31 11:13:19.517

abstract: E2A-PBX1 is expressed as a consequence of a recurring chromosomal translocation seen in 5% of acute lymphoblastic leukemia cases.  We recently reported that substitution of a leucine residue (L20A) within the N-terminal transcriptional activation domain (AD1) of E2A-PBX1 markedly impairs binding to the KIX domain of CBP/p300 and, importantly, leukemia induction in a mouse bone marrow transplantation model.  Since both the protein-protein interaction and consequent leukemogenesis rely on a focal contact point and might therefore be susceptible to antagonism by small molecules, we devised a cell-free assay based on fluorescence anisotropy (FA) to detect binding of a fluorescently labeled peptide derived from AD1 of E2A-PBX1 (FITC-E2A) with recombinantly expressed KIX domain. The optimized FA assay reveals a dissociation constant of 2 µM for the wild-type interaction and correctly detects disruption of the complex by naphthol AS-E phosphate, a compound previously shown to antagonize KIX binding. The optimized FA assay was used to screen the Prestwick, Spectrum and Chembridge libraries containing 12400 compounds in total. Of the initial 43 positive hits from the libraries, 10 caused a reproducible decrease in FA.  Since intrinsic small molecule fluorescence can produce false positive results in the FA-based screen, intrinsically fluorescent compounds were excluded from further analysis unless they could be shown to bind to KIX.  Two hits, L1 and C2, were intrinsically fluorescent but demonstrated KIX interactions and one hit, P9, was not intrinsically fluorescent.  These three compounds were tested for their ability to inhibit binding of a larger portion of E2A (residues 1 to 483) to full length CBP in a pull down assay with only compound P9 demonstrating efficacy.  Further characterization of P9 by NMR showed no binding to KIX, however evaluation by FA showed binding to FITC-E2A with a 20 µM affinity.  A cell-based cytotoxicity assay demonstrated that compound P9 was slightly more toxic on leukemic cells that express E2A-PBX1, compared to leukemic cells lacking E2A-PBX1 expression.  Mammalian two-hybrid analysis did not provide details of the effects of P9 on the E2A:KIX interaction.  We expect the identification of a novel compound, P9, capable of disrupting the oncogenic E2A-PBX1:CBP interaction, to guide the development of effective, less toxic leukemia drugs and provide new tools for elucidating the molecular mechanisms of leukemia induction by E2A-PBX1.

abstract: M.Sc.


title: Labor Market Behavior of Sciences and Engineering Doctorates: Three Essays.

contributor:
Imai, Susumu
Ferrall, Christopher
Economics

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subject:
High-Skill Labor Markets
Applied Econometrics
Postgraduate Education
Migration of High-Skill Labor

abstract: Thesis (Ph.D, Economics) -- Queen's University, 2009-08-31 11:33:27.809

abstract:
In this dissertation I study the labor market behavior of sciences and engineering (S&E)
doctorates trained and employed in the US. The first essay is an empirical study of task-to-task transitions based on the Survey of Doctorate Recipients (1973-2001). It first assesses
the relevance of the careers of doctorates to S&E in general, and research and development
(R&D) in particular. Second, it evaluates the participation rates and mobility patterns of
doctorates in careers of different types using a transition model with independent competing
risks. The second essay extends the empirical framework described above and specifies
a dynamic model of occupational choices with symmetric learning about one of the task-
specific abilities and dependence on past performance to explain the empirical career patterns
described in the first essay. The predictions of the model are used to evaluate the effects
of two counterfactual experiments on the supply of research skill. The third essay studies
geographic choices for first employment of doctorates using the Survey of Earned Doctorates
(SED) 1957-2005. Decisions of Americans, Canadians, and third country nationals to stay
in the US after their PhD versus moving to Canada are compared. Individual characteristics
and differences in political and economic conditions and career opportunities in the US versus
Canada are evaluated to explain the observed differences in the choice of location.

abstract: PhD


title: An Analysis of the Relationship Between Information and Communication Technology (ICT) and Scientific Literacy in Canada and Australia

contributor:
Freeman, John G.
Education

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subject: ICT

subject: Science Education

subject: Large-Scale Assessment

abstract: Thesis (Master, Education) -- Queen's University, 2009-08-31 11:14:15.59

abstract:
Despite the lack of substantial evidence for improvement in the quality of teaching and learning with information and communication technology (ICT), governmental organizations, including those of Canada and Australia, have made large investments into ICT. This investment has been largely predicated on the hypothesized relationship between ICT and science achievement, and the need for ICT as a means of providing broad-scale training to meet the demand for a skilled workforce.
To better understand this possible relationship, this study used data from the 2006 administration of the Programme for International Student Assessment (PISA 2006) to determine the extent to which scientific literacy is predicted by student- and school-level variables related to ICT, after adjusting for student demographic characteristics and school characteristics.
The findings suggest that, once student demographic characteristics and school characteristics have been accounted for, students with prior experience with ICT, who browse the Internet more frequently, and who are confident with basic ICT tasks earned higher scientific literacy scores. Gender differences existed with respect to types of productivity and entertainment software used; this difference may be attributed to personal choice and initiative to learn ICT. Finally, differences in ICT use between Canada and Australia, particularly with school use, may be due to initiatives in Australia (e.g., National Goals of Schooling for the Twenty-first Century) that promote the increased use of ICT in classrooms.

abstract: M.Ed.


title: Recommendations for Minimal and Optimal Amounts of Physical Activity to Reduce the Risk of Dyslipidemia in Youth

contributor:
Janssen, Ian
Kinesiology and Health Studies

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subject:
Dose-Response
Moderate-to-Vigorous Physical Activity
Lipids/Lipoproteins
Accelerometer
Self-Report
Youth
Physical Activity

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-07 08:48:03.896

abstract:
Background: Physical inactivity has been consistently associated with numerous negative health outcomes that track from childhood into adulthood, making physical activity a special concern in the pediatric population.  Dose-response studies are particularly useful when trying to understand the minimal and optimal amounts of physical activity needed to reduce the risk of negative health outcomes.  Unfortunately, previous work within youth has relied on self-reported measures of physical activity, and this research does not provide a clear picture of the true relation between physical activity and health.
Objectives: Manuscript 1. Describe the dose-response relation between dyslipidemia and moderate-to-vigorous physical activity (MVPA) in youth.  Manuscript 2. Quantify the difference between self-reported and objectively measured MVPA in youth.  Taken together, the overall objective of this thesis was to examine the dose-response relation between objectively measured MVPA and dyslipidemia in youth and determine how this may affect current Canadian physical activity guidelines.
Methods: Both manuscripts used data from the U.S. National Health and Nutrition Examination Survey.  Fractional polynomial regression modeling was used to fit the dose-response curves between MVPA and lipid/lipoprotein measurements.  Regression analysis as well as a Bland-Altman plot was used to explain the discrepancy between self-reported and objective measures of MVPA.  All analyses were completed using SAS statistical software.
Results: Manuscript 1. Risks for high-risk HDL-cholesterol and triglyceride values decreased in a curvilinear manner with increasing minutes of MVPA.  The greatest reduction in risk occurred within the first 30 min/d of MVPA.  The relation between level of MVPA and LDL-cholesterol was unclear.  Manuscript 2. The average youth over-reported their MVPA by ~30 min/d.  The over-reporting was not mediated by basic demographic factors; however, the difference in reporting was systematic in nature such that inactive youth over-reported to the greatest extent.
Conclusions: Manuscript 1. Youth need to accumulate 30 min/d of MVPA to greatly reduce their risk for dyslipidemia.  Manuscript 2.  Youth tend to over-report their daily MVPA by approximately 30 min/d.  Combined, the results from this thesis suggest that physical activity recommendations for cardiovascular health in youth should suggest a minimum of 30 min/d of MVPA and preferred level of 60 min/d.

abstract: M.Sc.


title: Using General Strain Theory to Understand Drug and Alcohol Use in Canada: An Examination of how Strain, its Conditioning Variables and Gender are Interrelated

contributor:
Baron, Stephen W.
Sociology

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subject:
General Strain Theory
Strain
Conditioning
Drug
Alcohol
Gender
Deviance
Use
Crime
Criminology
Interaction
Logistic

abstract: Thesis (Master, Sociology) -- Queen's University, 2009-08-31 12:12:25.288

abstract:
This thesis uses the Canadian Drugs and Alcohol survey conducted in 1994 by Statistics Canada to explore how Agnew’s (1992, 2001, 2006) general strain theory can help to understand drug and alcohol use in Canada. Agnew argues that experiences of strain, which include an array of negative life events, produce a negative emotional response which creates pressure for corrective action. In postulating why certain individuals are more likely to react to strain with deviant behaviour, Agnew (1992, 2001, 2006) emphasizes the importance of variables that condition the effects of strain on deviance. It is argued that people are less likely to respond to strain with deviant coping strategies depending upon their levels of social control, constraint, social support and deviant peers and values (Agnew 1992; Broidy and Agnew 1997; Agnew 2006).

Results are very supportive of GST as measures of objective and subjective strains as well measures of the conditioning variables are consistently associated with drug and alcohol use in hypothesized directions; strain measures also tended to interact with conditioning variables in associations with substance use. Hypotheses surrounding gender differences were also supported as females generally scored higher than males on measures argued to protect against the effects of strain and lower on measures argued to encourage deviant coping. Additionally, objective financial strain tended to have a stronger effect on male substance use while subjective strains tended to be more important in the prediction of female substance use. Avenues for further research are discussed including ways to ameliorate the adaptation of GST to gendered substance use patterns.

abstract: M.A.


title: Lightweight Top-K Analysis in DBMSs Using Data Stream Analysis Techniques

contributor:
Martin, Patrick
Computing

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subject:
Data Stream Analysis
Top-k Analysis

abstract: Thesis (Master, Computing) -- Queen's University, 2009-08-31 12:42:48.944

abstract:
Problem determination is the identification of problems and performance issues that occur in an observed system and the discovery of solutions to resolve them. Top-k analysis is common task in problem determination in database management systems. It involves the identification of the set of most frequently occurring objects according to some criteria, such as the top-k most frequently used tables or most frequent queries, or the top-k queries with respect to CPU usage or amount of I/O.
Effective problem determination requires sufficient monitoring and rapid analysis of the collected monitoring statistics. System monitoring often incurs a great deal of overhead and can interfere with the performance of the observed system.  Processing vast amounts of data may require several passes through the analysis system and thus be very time consuming.
In this thesis, we present our lightweight top-k analysis framework in which lightweight monitoring tools are used to continuously poll system statistics producing several continuous data streams which are then processed by stream mining techniques. The results produced by our tool are the “top-k” values for the observed statistics.  This information can be valuable to an administrator in determining the source of a problem.
We implement the framework as a prototype system called Tempo.  Tempo uses IBM DB2’s snapshot API and a lightweight monitoring tool called DB2PD to generate the data streams. The system reports the top-k executed SQL statements and the top-k most frequently accessed tables in an on-line fashion. Several experiments are conducted to verify the feasibility and effectiveness of our approach. The experimental results show that our approach achieves low system overhead.

abstract: M.Sc.


title:
Detection and Analysis of \\
Detection and Analysis of Near-Miss Software Clones

contributor:
Cordy, James R.
Computing

format:
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subject:
Software Clone
Clone Detection and Analysis
Software Maintenance

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2009-08-31 14:05:30.233

abstract: Software clones are considered harmful in software maintenance and evolution. However, despite a decade of active research, there is a marked lack of work in the detection and analysis of near-miss software clones, those where minor to extensive modifications have been made to the copied fragments. In this thesis, we advance the state-of-the-art in clone detection and analysis in several ways. First, we develop a hybrid clone detection method, called NICAD, that can detect both exact and near-miss clones with high precision and recall and with reasonable performance. Second, in order to address the decade of vagueness in clone definition, we propose an editing taxonomy for clone creation that models developers' editing activities in the copy/pasted code in a top-down fashion. NICAD is designed to address the different types of clones in the editing taxonomy. Third, we have conducted a scenario-based qualitative comparison and evaluation of all of the currently available clone detection techniques and tools in the context of a unified conceptual framework. Using the results of this study one can more easily choose the right tools to meet the requirements and constraints of any particular application, and can identify opportunities for hybridizing different techniques. The hybrid architecture of NICAD was derived from this study. Fourth, in order to evaluate and compare the available tools in a realistic setting and to avoid the challenges and huge manual effort in validating candidate clones, we have developed a mutation-based framework that automatically and efficiently measures (and compares) the recall and precision of clone detection tools for different fine-grained clone types of the proposed editing taxonomy. We have evaluated NICAD using this framework and found that it is capable of detecting different types of clones with high precision and recall. Finally, we have conducted a large scale empirical study of cloning in open source systems, both to evaluate NICAD and to study the cloning characteristics of these systems in several different dimensions. The study has demonstrated that NICAD is capable of accurately finding both exact and near-miss function clones even in large systems and different languages, and that there seem to be a large number of clones in those systems.

abstract: PhD


title: Making Sure Hungry Plants Get Fed: The Dual-Targeted Purple Acid Phosphatase Isozyme AtPAP26 is Essential for Efficient Acclimation of Arabidopsis Thaliana to Nutritional Phosphate Deprivation

contributor:
Plaxton, William C.
Biology

format:
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subject:
Phosphate Starvation
Arabidopsis
Purple Acid Phosphatase

abstract: Thesis (Master, Biology) -- Queen's University, 2009-09-01 09:46:39.302

abstract: Acid phosphatases (APases; E.C. 3.1.3.2) catalyze the hydrolysis of phosphate (Pi) from Pi monoesters and anhydrides within the acidic pH range. Induction of intracellular and secreted purple acid phosphatases (PAPs) is a widespread plant response to nutritional Pi-deficiency. The probable function of intracellular APases is to recycle Pi from expendable intracellular organophosphate pools, whereas secreted APases likely scavenge Pi from the organically bound Pi that is prevalent in most soils. Although the catalytic function and regulation of plant PAPs have been described, their physiological function in plants has not been fully established. Recent biochemical and proteomic studies indicated that AtPAP26 is the predominant intracellular (vacuolar) and a major secreted purple APase isozyme upregulated by Pi-starved (-Pi) Arabidopsis thaliana. The in planta function of AtPAP26 was assessed by molecular, biochemical, and phenotypic characterization of a homozygous Salk T-DNA insertion mutant. Loss of AtPAP26 expression resulted in the elimination of AtPAP26 transcripts and 55-kDa immunoreactive AtPAP26 polypeptides, correlated with a 9- and 5-fold decrease in extractable shoot and root APase activity, respectively, as well as a 40% reduction in secreted APase activity of –Pi seedlings. The results corroborate previous findings implying that AtPAP26 is: (i) the principal contributor to Pi starvation inducible APase activity in Arabidopsis, and (ii) controlled post-transcriptionally mainly at the level of protein accumulation. Total shoot free Pi level was about 40% lower in –Pi atpap26 mutants relative to wild-type controls, but unaffected under Pi-sufficient conditions. Moreover, shoot, root, inflorescence, and silique development of the atpap26 mutant was impaired during Pi deprivation, but unaffected under Pi-replete conditions, or during nitrogen or potassium-limited growth, or oxidative stress. The results suggest that the hydrolysis of Pi from organic-phosphate esters by AtPAP26 makes an important contribution to Pi-recycling and scavenging in –Pi Arabidopsis.

abstract: M.Sc.


title: Moral Distress in a Non-Acute Continuing Care Setting: the Experience of Registered Nurses

contributor:
Lamb, Marianne
Nursing

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subject:
Moral Distress
Nursing
Registered Nurse
Moral

abstract: Thesis (Master, Nursing) -- Queen's University, 2009-09-01 10:02:08.043

abstract:
The moral distress experiences of Registered Nurses who work in non-acute, continuing care settings were examined using qualitative methods.  Previous research suggests that in general, nurses experience moral distress when they are not able to pursue actions in accordance with their moral conscience. Moral distress in nurses is expressed negatively in both the nurses’ professional and personal lives. However, most research on moral distress among nurses has focused on acute care settings.

     Registered Nurse participants were recruited from non-acute continuing care settings and described their experiences of moral conflict and distress. Particular attention was placed on the nurses’ experiences and reactions to their experience. The findings from this study indicated that as in other settings, moral distress is present in Registered Nurses practicing in non-acute continuing care. The nurses’ practicing in non-acute continuing care settings experienced moral distress after facing a barrier to their moral conscience involving organizational functioning, end of life decisions, patient advocacy, and resource utilization. Nurses experienced feelings including powerlessness, concern, regret, disappointment, suspicion of others, and feeling devalued. Future studies may focus further on the subspecialties in the non-acute continuing care sector. Research on strategies to resolve moral distress and research on the effectiveness of current interventions to combat moral distress among Registered Nurses in this setting should be pursued.

abstract: MNSc.


title: Imaging Biologically-Based Clathrate Hydrate Inhibitors

contributor:
Walker, Virginia K.
Biology

subject:
Antifreeze Proteins
Clathrate Hydrates

abstract: Thesis (Master, Biology) -- Queen's University, 2009-09-01 10:04:00.72

abstract:
The unscheduled formation of gas hydrate plugs in oil and gas pipelines, which can lead to serious mechanical and personnel damage, is a problematic issue in the petroleum industry. Traditionally, thermodynamic inhibitors such as methanol have been used to control the formation of gas hydrates, but due to the large expenses and ecological risks associated with its use there is increased interest in the use of alternative hydrate inhibitors. They include kinetic inhibitors (KIs) and antiagglomerants (AAs) and as their names imply, function by interfering with the kinetics of hydrate formation and hydrate agglomeration.
Recently, antifreeze proteins (AFPs) have shown to inhibit hydrates and have been proposed as hydrate inhibitors.  Normally, AFPs function to protect the tissues of various organisms during freezing conditions. Initially they were found in polar fish, and were later recognized in insects, plants and microorganisms. AFPs are thought to function by lowering the freezing point of water through an adsorption-inhibition mechanism.
This thesis has shown that antifreeze proteins (AFPs) are able to modify the crystal morphologies of structure II (sII) tetrahydrofuran (THF) similarly to the KI poly-N-vinylpyrrolidone (PVP) by adhering to the hydrate surface and inhibiting crystal growth. The AFPs were also tested on a high-pressure sII methane/ethane/propane hydrate and proved to have superior hydrate inhibition to PVP. Yet, the expense of purifying AFPs makes them impractical for industrial purposes, thus investigations into the use of cold-adapted bacteria as hydrate inhibitors proved that isolates capable of adsorbing to THF hydrate showed the most effective THF hydrate inhibition. These findings suggest a potential for the future development of biologically-based hydrate inhibitors.

abstract: publication of the material

abstract: M.Sc.


title: Self-realization in John Dewey and Confucius: its philosophical and educational features

contributor:
Johnston, James Scott
Education

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subject: self-realization; John Dewey; Confucius; education

abstract: Thesis (Master, Education) -- Queen's University, 2009-09-01 10:34:58.687

abstract: This thesis attempts to present John Dewey and Confucian views regarding self-realization and its implication for education. Although there is an increasing body of comparative literature examining the two schools of thought, the examination of the two philosophers’ theories from a perspective of self-realization is greatly lacking. Examining Deweyan notion of self as social, ethical and ever-growing, and the Confucian concept of self as Ren (Humane), He (Harmonious) and Cultivating, self-realization will be illustrated as the expansion, enhancement and enrichment of the individual resulting from a closed gap between oneself and one’s environment. Such unity of self as the feature of self- realization not only illustrates Deweyan and Confucian philosophical theories toward the development of an individual, it also reflects their notions of education as means and ends to realize unification at all levels.

abstract: M.Ed.


title: Generation and Optimization of Local Shape Descriptors for Point Matching in 3-D Surfaces

contributor:
Greenspan, Michael A.
Electrical and Computer Engineering

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subject: Computer Vision

subject: Range Data

subject: Object Recognition

subject: Tracking

subject: Local Shape Descriptor

subject: Point Matching

subject: Pose Estimation

subject: Pose Acquisition

subject: 3-D

subject: 3D

subject: Point Cloud

subject: Satellite Tracking

subject: Optimization

subject: Range Image Processing

subject: Range Image

subject: RANSAC

subject: Registration

subject: Alignment

subject: Surface

subject: Computational Geometry

subject: Detection

subject: Localization

subject: Model-Based

subject: Object Identification

subject: Point Correspondence

subject: Feature Selection

subject: VD-LSD

subject: LSD

subject: Genetic Algorithm

subject: Simulated Annealing

subject: Forward Feature Selection

subject: Multivariate Features

subject: Subset Selection

subject: Local Properties

subject: LIDAR

subject: Dense Stereo

subject: Stereo

subject: Precision

subject: Feature Matching

subject: Machine Learning

subject: Training

subject: Learning Phase

subject: Preprocessing

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-09-01 11:07:32.084

abstract:
We formulate Local Shape Descriptor selection for model-based object recognition in range data as an optimization problem and offer a platform that facilitates a solution. The goal of object recognition is to identify and localize objects of interest in an image. Recognition is often performed in three phases: point matching, where correspondences are established between points on the 3-D surfaces of the models and the range image; hypothesis generation, where rough alignments are found between the image and the visible models; and pose refinement, where the accuracy of the initial alignments is improved. The overall efficiency and reliability of a recognition system is highly influenced by the effectiveness of the point matching phase. Local Shape Descriptors are used for establishing point correspondences by way of encapsulating local shape, such that similarity between two descriptors indicates geometric similarity between their respective neighbourhoods.
We present a generalized platform for constructing local shape descriptors that subsumes a large class of existing methods and allows for tuning descriptors to the geometry of specific models and to sensor characteristics. Our descriptors, termed as Variable-Dimensional Local Shape Descriptors, are constructed as multivariate observations of several local properties and are represented as histograms. The optimal set of properties, which maximizes the performance of a recognition system, depend on the geometry of the objects of interest and the noise characteristics of range image acquisition devices and is selected through pre-processing the models and sample training images. Experimental analysis confirms the superiority of optimized descriptors over generic ones in recognition tasks in LIDAR and dense stereo range images.

abstract: PhD


title: Synthesis of photochemically active complexes for DNA recognition and binding

contributor:
Petitjean, Anne
Chemistry

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subject:
DNA recognition
photoadduct

abstract: Thesis (Master, Chemistry) -- Queen's University, 2009-09-01 11:58:42.728

abstract: The objective of this thesis is to synthesize and examine the photophysical and structural properties of 3-(pyridin-2-yl)imidazo[1,5-a]pyridine (P) and 3-(pyridin-2-yl)imidazo [1,5-a]pyridine (IQ) based cations and their potential use as DNA binding agents. The P ligand was aimed to compare with the IQ ligand as they have similar structures. Two series of compounds were synthesized; one series comprising organic cations, including PC2, PC3, PC4, IQC2 and IQC3. The other one contains ruthenium complexes Ru(bpy)2P, Ru(bpy)2IQ and Ru(P)3). Compounds were prepared as Cl-, Br- and/or PF6- salts. All compounds were characterized by NMR, UV-vis, luminescescence and electrochemistry, when applicable. The results show that P and IQ based organic cations have similar electrochemical properties, and may be candidates for guanine photo-oxidation. However, [Ru(bpy)2P](PF6)2, [Ru(bpy)2IQ](PF6)2 and [Ru(P)3](PF6)2 do not seem to have reduction potentials in the excited states that are appropriate for nucleic base photo-oxidation.

abstract: M.Sc.


title: Two-digit number comparison

contributor:
Mewhort, Douglas J. K.
Psychology

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subject:
number comparison
digit similarity

abstract: Thesis (Master, Psychology) -- Queen's University, 2009-09-02 11:59:06.647

abstract: Magnitudes of numbers influence numerical inequality judgments of people.  Do symbols representing numbers also affect numerical inequality judgments?  To answer the question, I manipulated digit similarity in two-digit number comparison tasks.  During the experiment, the participants took part in two comparison tasks – the judging-larger task and the judging-smaller task.  Given pairs of two-digit numbers, the participants were required to make numerical inequality judgments (judging larger or judging smaller).  To investigate the effect of digit similarity, two kinds of number pairs were used. Two-digit number pairs consisting of same-digits numbers (e.g., 21 – 12) and two-digit number pairs consisting of different-digits numbers (e.g., 21 – 30) were presented at random.  The participants needed more time to compare the same-digits number pairs than the different-digits pairs.  The result was independent of the findings in number comparison studies such as the numerical-distance effect (Moyer & Landauer, 1967) and the unit-decade compatibility effect (Nuerk, Weger, & Willmes, 2001).  The present study poses challenge to the current theories of two-digit number comparison.

abstract: M.Sc.


title: A Geometric Approach to Energy Shaping

contributor:
Lewis, Andrew D.
Mansouri, Abdol-Reza
Mathematics and Statistics

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subject:
Nonlinear control theory
Geometric control
Geometric mechanics
Energy shaping

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2009-09-02 12:12:55.051

abstract:
In this thesis is initiated a more systematic geometric exploration of energy shaping. Most of the previous results have been dealt wih particular cases and
neither the existence nor the space of solutions has been discussed with any degree of generality. The geometric theory of partial differential equations originated by Goldschmidt and Spencer in late 1960s is utilized to analyze the partial differential equations in energy shaping. The energy shaping partial differential equations
are described as a fibered submanifold of a $ k $-jet bundle of a fibered manifold. By revealing the nature of kinetic energy shaping, similarities are noticed between the problem of kinetic energy shaping and some well-known problems in Riemannian geometry. In particular, there is a strong similarity between kinetic energy shaping and the problem of finding a metric connection initiated by Eisenhart and Veblen. We notice that the necessary conditions for the set of so-called $ \lambda $-equation restricted to the control
distribution are related to the Ricci identity, similarly to the Eisenhart and Veblen metric connection problem. Finally, the set of $ \lambda $-equations for kinetic energy shaping are coupled with the integrability results of potential energy shaping. The procedure shows how a poor design of closed-loop metric can make it impossible to achieve any flexibility in the character of the possible closed-loop
potential function. The integrability results of this thesis have been used to answer some interesting questions about the energy shaping. In particular, a geometric proof is provided which shows that linear controllability is sufficient for energy shaping of linear simple mechanical systems. Furthermore, it is shown that all linearly controllable mechanical control systems with one degree of underactuation can be stabilized using energy shaping
feedback. The result is geometric and completely characterizes the
energy shaping problem for these systems. Using the geometric approach of this thesis, some new open problems in energy shaping
are formulated. In particular, we give ideas for relating the kinetic energy shaping problem to a problem on holonomy groups.
Moreover, we suggest that the so-called Fakras lemma might be used for investigating the stabilization condition of energy shaping.

abstract: PhD


title: Investigating Antigen Presentation by Inactivated Lymphocytic Choriomeningitis Virus and by Baculovirus Encoding the LCMV-Nucleoprotein

contributor:
Basta, Sameh
Microbiology and Immunology

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subject:
LCMV
Baculovirus
Inactivated Virus
Cellular Immune Response

abstract: Thesis (Master, Microbiology & Immunology) -- Queen's University, 2009-09-02 15:30:13.883

abstract: Professional antigen presenting cells (pAPCs) process and present antigens on their cell surface in association with MHC class I molecules through two general pathways: direct or cross-presentation.  The process of antigen presentation by pAPCs to naïve T cells resulting in their proliferation and differentiation into activated cytotoxic lymphocytes (CTLs) is called T cell priming.  In these studies, we examine the cross-presentation of antigens from two non-replicating viruses: inactivated Lymphocytic Choriomeningitis virus (LCMV), and recombinant baculovirus encoding the LCMV nucleoprotein (NP). Since effective activation of pAPCs is essential for efficient priming of CD8+ T cells and CTL activation, and because infection with inactivated viruses generally induces an extremely poor level of CTL activation, we examined the activation state of pAPCs by measuring their cytokine profiles following infection to help further delineate their involvement in the CTL response to inactivated viruses.  Our results indicate a pro-inflammatory cytokine mRNA upregulation in pAPCs in response to the inactivated virus, similar to the cytokine profiles subsequent to live LCMV infection, but to a lesser extent.  In these studies, we also examined CTL activation following infection with inactivated LCMV and bAc-NP.  We have demonstrated that the presentation of antigens from inactivated LCMV and bAC-NP results in a low level of CTL activation in vivo, though there is an undetectable level of CTL activation in vitro, in comparison to activation following infection with the live virus.  Ultimately, the characterization of the cytokine profiles of pAPCs and the CD8+ T cell profiles induced in response to inactivated LCMV or the baculovirus derived NP may lead to a better understanding of how cross-presentation of these viral antigens may occur.  This information may be applied to enhance the process of pAPC activation and T cell priming, for the induction of more effective cellular immune responses and the generation of stronger protective immunity.

abstract: M.Sc.


title: Molecular Identification and Messenger RNA Levels of a Monocarboxylate Transporter (MCT) in Fundulus Heteroclitus, a Hypoxia Tolerant Teleost Fish

contributor:
Wang, Yuxiang S.
Biology

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subject:
Biology
Comparative Physiology

abstract: Thesis (Master, Biology) -- Queen's University, 2009-09-02 15:54:00.643

abstract: Monocarboxylate transporters (MCTs) are bi-directional symporters that couple proton movement to a variety of glycolytic metabolites, including lactate and pyruvate.  As such, MCTs not only play a crucial role in pH regulation, but could also function in the distribution of substrates between organelles, cells and tissues. This function may be critically important during hypoxia, when tissues depend on glycolytic flux for energy. We have examined the role of MCTs during hypoxia in an estuarine teleost, the common killifish, Fundulus heteroclitus, that routinely encounters environmental hypoxia. We cloned and sequenced a killifish MCT that resembled the MCT-2 isoform of mammals, and examined its expression pattern and regulation during hypoxia using real-time quantitative PCR.   Killifish MCT mRNA levels were highest in the intestine (~2x) and lowest in the heart (~0.2x) as compared to the expression in the liver.  Exposure to hypoxia (0.5 mg L-1) resulted in a significant increase in plasma lactate and glucose within 4 hours.  However pyruvate and glycogen concentration in white muscle did not change significantly during this time. We observed no change in the mRNA levels of this MCT isoform in any tissue during 16h of hypoxia. This could indicate the regulation of this MCT at another level, a secondary role in hypoxia, or a role for this isoform unrelated to hypoxia tolerance.

abstract: M.Sc.


title: Machinery-Related Operational Factors as Determinants of Injury on Canadian Prarie Farms

contributor:
Peng, Paul Yingwei
Pickett, William
Community Health and Epidemiology

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subject:
Occupational Injury
Agriculture
Public Health

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2009-09-03 10:51:31.608

abstract:
Background: Agriculture remains one of the most hazardous occupations in Canada.
Approximately one-half of all agricultural injuries are due to machinery. The etiology of machinery-related injury remains poorly understood.

Objectives: (1) To evaluate the relative importance of two representative safety practices (i.e. safety device use and routine maintenance) and their relationship with machinery-related injury;(2) To evaluate the roles of situational factors and safety practices in the occurrence of entanglement injuries caused by machinery.

Methods: Objective 1. Participants were administered the Saskatchewan Farm Injury  Cohort Study baseline survey for a one-year period of recall (2006). Relationships between the machinery-related injury outcome and two safety practices were analyzed cross-sectionally using the farm as the unit of analysis; Objective 2. A descriptive case-series was analyzed for factors surrounding 41 machinery entanglements using data from the Case-Control Farm Machinery Injury Study (2000-2005).

Results: Objective 1. Limited use of safety devices on machinery during farm operations was associated with higher risks for injury (RR 1.94; 95% CI 1.13 to 3.33; ptrend=0.02). Lower routine maintenance scores were associated with significantly reduced risks for injury (RR 0.54; 95% CI 0.29 to 0.98; ptrend=0.05). Objective 2. The majority of entanglements occurred during a few
machinery-related tasks, namely (1) field adjustments of machinery; (2) product handling and conveyance; and (3) driveline attachments and servicing. Both expected and unanticipated hazards inherent to these tasks affected the behaviour of farmers, leading to entanglements.

Conclusions: Objective 1. The first finding implies that injury prevention programs require continued focus on the use of safety devices on machinery. The second finding could indicate that maintenance itself is a risk factor, or that more modern equipment that requires less maintenance places the operator at lower risk. These findings provide etiological data that confirm the
practical importance of operational safety practices as components of injury control strategies on farms. Objective 2. Systemic changes are required to improve existing machinery safety practices through engineering, work methods and work practice modifications. In addition to design
solutions, occupational health and safety strategies should consider activities associated with hazardous situations to inform the content of training and educational efforts.

abstract: M.Sc.


title: Interleukin-17 modulates Ca2+ currents and neurite outgrowth in sympathetic neurons

contributor:
Lomax, Alan E.
Physiology

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subject:
sympathetic nervous system
inflammatory bowel disease

abstract: Thesis (Master, Physiology) -- Queen's University, 2009-09-03 11:33:53.63

abstract: The gastrointestinal (GI) tract is subject to regulation by several neuronal networks, one of which is the sympathetic nervous system (SNS). Inflammatory bowel diseases (IBD), most importantly Crohn’s disease and ulcerative colitis, are chronic diseases of the GI tract that result in such functional symptoms as abdominal pain and diarrhea. These symptoms suggest an important role for dysregulation of the SNS in IBD, since this branch of the autonomic nervous system aids in regulation of blood flow, secretion and motility. Inflammatory cytokines that are elevated in the serum and tissue of IBD patients can have wide-ranging effects on neuronal function in vitro, and may be responsible for the functional alterations observed in vivo. With these neuronal alterations in mind, we hypothesized that interleukin-17, a novel cytokine with a central role in the pathogenesis of IBD, modulates the properties of sympathetic neurons innervating the gastrointestinal tract. Using electrophysiological techniques and Ca2+ imaging, we examined the effect of IL-17 on currents passing through voltage-gated Ca2+ channels in neurons from the superior mesenteric ganglion, which innervates the gut, and found that IL-17 inhibited these currents. In parallel, we found that IL-17 enhances the growth of sympathetic neurites in vitro. These effects depend upon activation of the nuclear factor κB (NF-κB) pathway, and do not appear to require glial cells. Therefore, dysregulated neural function during IBD may be due to direct effects of IL-17 on sympathetic neurons.

abstract: M.Sc.


title: Classical and Quantum Optical Properties of Slow Light Photonic Crystal Waveguides

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subject:
slow light
photonic crystal

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-09-03 12:29:01.696

abstract: Photonic crystals are optical materials where patterning of dielectrics on sub-wavelength length scales creates unusual optical properties such as waveguides with propagation speeds much slower than the vacuum speed of light. In this thesis, I examine the classical and quantum optical properties of such structures, specifically the enhancement of photon emission rate from a single quantum dot embedded in the waveguide (the Purcell Effect) and extrinsic scattering from an injected waveguide mode due to fabrication imperfections. The photon emission rate is found to be significantly enhanced over a large bandwidth in slow light photonic crystal waveguides and I provide detailed results for optimizing the emission properties of a novel photonic crystal ridge waveguide to suite a given application. Using an incoherent scattering theory, I show how slow light propagation enhances extrinsic scattering from unavoidable manufacturing imperfections leading to back scattering and radiation loss that scale with the group velocity v_g, as v_g^{-2} and v_g^{-1} respectively. I then improve the modeling of scattering using a coherent, multiple scattering approach to explain the experimental observation of disordered resonances in slow light waveguide modes. The theoretical predictions show good agreement with experimental measurements. This document provides a thorough introduction to the properties and problems of slow light photonic crystal waveguides.

abstract: M.Sc.


title: Development and Characterization of Biodegradable Elastomers for Localized Angiogenic Growth Factor Delivery

contributor:
Amsden, Brian
Chemical Engineering

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subject:
Degradable Elastomers
Therapeutic Angiogenesis
Osmotic Delivery

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-09-03 14:54:28.709

abstract: Therapeutic angiogenesis is a promising technique to treat ischemia by creating new blood vessels. The aim of this thesis was to develop and characterize biodegradable elastomers for localized delivery of growth factors and to investigate the ability of released growth factors to induce angiogenesis. An osmotic delivery mechanism using photo-cross-linked elastomers based on trimethylene carbonate (TMC) was used to deliver vascular endothelial growth factor (VEGF165) and hepatocyte growth factor (HGF) alone or in combination at two different doses. It was hypothesized that elastomers made of TMC can provide an effective osmotic release using trehalose as a main osmotigen and that the use of TMC would eliminate the microenvironmental pH drop implicated in denaturing acid sensitive growth factors. To obtain an insight into the degrading zone in which growth factors will be released, the in vivo degradation mechanism and tissue response were investigated. The in vivo degradation of D,L-lactide/ε-caprolactone (DLLACL) elastomers that degrade by hydrolysis was investigated for comparison. Cross-link-density played a significant role in the degradation pattern of DLLACL elastomers. TMC and TMCCL elastomers degraded by surface erosion and oxidation played a significant role in their in vivo degradation. To obtain an efficient release, the mechanical properties of TMC elastomers were tailored by copolymerizing TMC with CL and DLLA and/or by controlling the cross-link density. The delivery device was able to provide a sustained release of growth factors for longer than two weeks with no initial burst. Cell based bioactivity assays indicated that released growth factors were highly bioactive over the entire release period.  Microenvironmental pH studies using FITC-BSA indicated no significant drop in pH in TMC elastomers that contained small amounts of DLLA. Using 125I-VEGF165, it was found that the osmotic delivery can provide a direct in vivo-in vitro release correlation. Released growth factors were able to induce angiogenesis in rats when tested by subcutaneous implantation.  Angiogenesis was dose dependent for both VEGF165 and HGF. Combined release of VEGF and HGF achieved the best results. The formed blood vessels were stable during the active release period, and they were normal looking and connected to the surrounding vasculature.

abstract: PhD


title: The Impact of Efficacious Treatments for Major Depressive Disorder on Remission Rates of Specific Symptoms: A Re-Analysis of the Treatment of Depression Collaborative Research Program

contributor:
Harkness, Kate
Psychology

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subject:
depression
symptom specificity
treatment
CBT
IPT
antidepressant medications

abstract: Thesis (Master, Psychology) -- Queen's University, 2009-09-03 14:41:46.163

abstract: Major Depressive Disorder (MDD) is a highly prevalent mental disorder that will affect 12.2% of Canadians over the course of their lifetimes, and 4.8% annually (Patten, et al., 2006). One of the most robust findings in the MDD literature is that the gold-standard treatments – Cognitive-Behavioral Therapy (CBT), Interpersonal Psychotherapy (IPT), and anti-depressant medications - are equal in their efficacy, and superior to placebo. However, it is unclear whether rates of remission for certain types of symptoms differ among treatments with theoretically different mechanisms. This study re-analyzed data from the Treatment of Depression Collaborative Research Program, which included 158 adults with MDD randomized to CBT, IPT, imipramine or placebo. We statistically derived 4 factors from the baseline Hamilton Depression Rating Scale. We hypothesized that the rate of remission of somatic factors (sleep and appetite) would be most rapid in the group receiving imipramine plus clinical management (IMI-CM), and that the rate of remission for cognitive-affective factors would be fastest in IPT and CBT. Hierarchical regression analyses predicted the sum of symptom scores corresponding to each factor using linear and quadratic time (measured in weeks). Treatment-by-time interactions were entered in a stepwise fashion. There were no significant interactions found in the appetite factor, suggesting that all therapies acted on these symptoms at similar rates. Consistent with hypotheses, IMI-CM produced more rapid remission in sleep symptoms compared to psychotherapy. Surprisingly, IMI-CM was also more rapid at relieving cognitive-affective symptoms. The results lend partial support to the idea that different treatments for MDD may target specific symptoms at different rates according to their underlying mechanisms of action. The findings present some exciting possibilities for elevating response rates through empirically-based “tailored treatments”.

abstract: M.Sc.


title: Clean heat flux sensor for ash fouling monitoring

contributor:
Matovic, Miodrag
Mechanical and Materials Engineering

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subject:
ash fouling
heat flux

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-09-03 16:38:26.48

abstract: An ash monitoring system prototype that consists of a “clean” heat flux sensor and a “dirty” heat flux sensor was developed in this study. The “clean” heat flux sensor was studied numerically and experimentally while the “dirty” heat flux sensor was tested in the experiment. Two different measurement methods were applied on the “clean” sensor, one from the original study and one proposed in the present work. The new method required additional data processing procedures to be able to work in an on-line basis. Among the three data processing procedures developed in this study the central temperature difference procedure was found to be the most reliable one. Numerical results provided valuable information about the heat transfer pattern at the sensing element and also the performance of the sensor at high radiation heat flux levels. A rough calibration of both “clean” and “dirty” heat flux sensors was conducted experimentally. Nevertheless, the experimental results still served as a primary assessment for both sensors. Observed disagreements between the original study and the present one were probably caused by the modification of the sensor structure made in the present study. Sensitivity variation at high heat flux levels did not appear in the numerical results of either measurement method. Low overall sensor temperature change was believed to be the main reason as it meant less change in thermal properties of the sensing disc. Although the results of the study suggested that the proposed oscillation method was less attractive than the original one, it increased the possibility of resolving the surface characteristic variation problem that was considered crucial for the performances of the “clean” heat flux sensor regardless of the measurement method used.

abstract: M.A.Sc.