title: Oligo-Miocene Temperate Seagrass Limestones: Padthaway Ridge, South Australia

contributor: Geological Sciences and Geological Engineering

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subject: temperate carbonates, seagrass, Padthaway Ridge, Murray Basin, South Australia

abstract: Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-12-14 17:18:16.853

abstract:
The Padthaway Ridge is overlain by a thin veneer (< 20 m) of Oligo-Miocene bioclastic carbonates representing the southern most extent of the Mannum Formation, Murray Supergroup, and Murray Basin limestones.  The Mannum Formation is composed of warm-temperate carbonates rich in irregular echinoids, coralline algae, benthic foraminifers, and relict particles.  The respective lithology are mostly structureless, burrow-mottled, and cross-cut by Thalassinoides burrows.  These sediments are interpreted to have resulted from carbonate production along shallow, illuminated seafloors under high mesotrophic conditions.  The composition and texture is similar to that of modern temperate seagrass accumulations with the exception of the abundant mobile infauna and bioturbation, which are more akin to associated intercalated and adjacent barren sands.  The Mannum Formation is therefore interpreted as an amalgamation of these two environments.
	The ubiquitous relict grains and Fe-stained cements in the lithologies of the Mannum Formation are thought to be the product of Fe redox pumping within the subsurface of seagrass meadows, whereby consolidated sediments endured prolonged and repeated exposure to juxtaposed destructive and constructive diagenetic conditions at the redox boundary.  Fluctuations in the organic carbon and oxygen influx to the subsurface are primarily a function of auto- and allogenic controls on seagrass density (i.e. turbidity, light, depth, hydrodynamics).
	The overlying Glenforslan Formation is interpreted as a seagrass-influenced deposit that accumulated under warm-temperate, low mesotrophic conditions and more rapid rates of sedimentation.   Relict grains, however, are absent from the Glenforslan Formation.  The subtle  change in trophic resources is thought to have caused a significant shift in primary and secondary production, from organic carbon- to carbonate-dominated.
	Assessment of previously described temperate seagrass facies together with this research comprise reliable criteria for identification of temperate seagrass depositional settings.  The signal of multigenerational accumulation, especially prominent in the Mannum Formation,  represents an amalgamation of environments that would be difficult to assess in modern settings.  The key attributes of temperate grass facies proposed herein allow for more accurate reevaluation of seagrass influenced, and relict rich lithologies in the rock record.

abstract: M.A.Sc.


title: Cellulitis:  Comorbidities as a determinant of hospital length-of-stay

contributor:
Ding, Keyue
Community Health and Epidemiology

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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:
cellulitis
hospital length-of-stay

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2009-11-18 11:43:07.897

abstract:
Background: Cellulitis is a common skin and soft-tissue infection that often recurs in some patients. Patients with presenting comorbid conditions may require hospitalization which increases the cost of treatment.  However, little is known about comorbid conditions as determinants for a patient’s hospital length-of-stay.
Objective: 1) To profile the characteristics of patients admitted to Ontario hospitals with a diagnosis of cellulitis according to key demographic, clinical and geographic factors; 2) To examine, among patients hospitalized with cellulitis, comorbidities as possible determinants of hospital length-of-stay.
Methods:   A retrospective cohort of 7863 patients was identified from the Discharge Abstract Database from April 1, 2006 to March 31, 2008.  The Charlson Comorbidity Index was used to measure patients’ comorbidities.  Univariate analyses were performed to describe the study population.  The chi-square test was used to assess the association between categorical variables.  The Kaplan-Meier product-limit method and log-rank test were used to estimate and to test the difference in the distributions of hospital lengths-of-stay between patients with and without comorbidities.  Cox regression modeling was used to estimate the comorbidities’ effect on hospital length-of-stay while adjusting for confounding factors.  The restricted means of lengths-of-stay were given to estimate and compare the average duration of hospitalization.  The effects of specific Charlson comorbidities on hospital length-of-stay were similarly investigated.
Results:  Forty-six percent (3588/7863) of patients were diagnosed with Charlson comorbidities.  Those patients were significantly older (p<.0001), and more likely to be female (p=.006) and to have lower limb cellulitis (p<.001) and C. difficile infections (p<.0001), compared to patients without comorbidities.  Patients with comorbidities stayed significantly longer in hospital (8.0 vs. 5.3 days, p<.0001).  Comorbidities independently decreased the instantaneous discharge rate by 37% (95% CI, 34% to 40%, p<.001).  Hospital lengths-of-stay increased with increasing index of comorbidity.  The means of hospital lengths-of-stay for patients with a cumulative index of 1, 2, 3, and 4 (or more than 4) were 7.4, 7.6, 8.8, and 9.7 days, respectively.
Conclusion:  The Charlson Comorbidity Index is predictive of longer hospital lengths-of-stay in adult patients diagnosed with cellulitis and may be a useful tool in the decision-making process during clinical management of these patients.

abstract: M.Sc.


title: Subcellular Localization and Trafficking of the RET Receptor Tyrosine Kinase: Implications for Signalling and Disease

contributor:
Mulligan, Lois M.
Pathology and Molecular Medicine

subject:
RET
Intracellular Trafficking
Thyroid Carcinoma

abstract: Thesis (Ph.D, Pathology & Molecular Medicine) -- Queen's University, 2009-11-19 22:51:47.38

abstract:
The RET proto-oncogene encodes a receptor tyrosine kinase (RTK) that is widely expressed in neuroendocrine tissues and is essential for embryonic development of the kidney and enteric nervous system.  Mutations leading to constitutive activation of the RET protein underlie various tumours of endocrine tissues.  Conversely, loss-of-function mutations of RET lead to Hirschsprung disease, a congenital disorder characterized by a loss of enteric neurons throughout the colon and small intestine.
Intracellular trafficking of RTKs through multiple cellular compartments has been shown to impact on downstream signalling.  To date, the intracellular trafficking of RET has not been investigated.  Here, we show that RET is rapidly internalized after activation and that trafficking to cytoplasmic endosomes plays an important role in downstream signalling.
RET is alternatively spliced into multiple isoforms that are co-expressed in cells; therefore, we further investigated RET internalization in an isoform-specific context. This study revealed a number of differences between RET isoforms including differences in sub-cellular localization pre-activation, rate of internalization, and ability to recycle to the plasma membrane.  Differential trafficking of RET isoforms alter their downstream signalling properties, providing an additional mechanism to explain the distinct contributions of RET isoforms to cellular processes.
Finally, we investigated the impact of altered sub-cellular localization in the context of thyroid carcinoma.  Activation of RET has been implicated in a number of thyroid tumours that differ in their inherent oncogenicity.  We observed that altered subcellular localization of oncogenic forms of RET, RET/PTCs, enhance their oncogenicity.  Interestingly, RET/PTC tumours are indolent and rarely metastasize compared to other RET-mediated forms of cancer.  Further investigation revealed that RET/PTC oncogenes are expressed off relatively weak promoters, resulting in quantitatively less RET/PTC oncoprotein expression in these tumours compared to mutant RET expression in more aggressive cancers.
Together, our results represent the first in-depth study of the trafficking properties of RET and indicate the importance of proper sub-cellular localization and trafficking in the maintenance of normal cell metabolism.

abstract: Chapter number 5 will be submitted for publication shortly.  To prevent possible competitors from viewing the manuscript, and avoid conflicting with the requirements of the journal, we request that it be restricted until publication.

abstract: PhD


title: Genomic Rearrangements in Autism Spectrum Disorders: Identification of Novel Candidate Genes

contributor:
Holden, Jeanette J. A.
Walker, Virginia K.
Physiology

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subject:
Autism Spectrum Disorders
Genetics
Chromosome abnormalities
Genomic rearrangements
Williams-Beuren Syndrome
Real-time PCR
Microarray
Association testing

abstract: Thesis (Ph.D, Physiology) -- Queen's University, 2009-11-20 00:35:11.727

abstract: There is evidence from family studies for the importance of genetic factors in the development of autism spectrum disorders (ASDs) but the identification of major genes has not been achieved to date. There are several reports of deletions and duplications in individuals with ASDs, some of which are not unique to an individual. In most cases, the frequencies and relevance of these abnormalities are unknown, as they have been identified serendipitously in one or a few individuals. My overall hypothesis was that such rearrangements would facilitate the identification of “culprit” genes associated with ASDs by identifying a small chromosomal region for candidate gene testing. I molecularly characterized two overlapping 2p15-2p16.1 deletions detected in unrelated individuals with confirmed autistic disorder (Subject 1) or autistic features (Subject 2), a 1.4Mb deletion on chromosome Xp22 (Subject 1) and a duplication of chromosome 7q11.23, reciprocal to the Williams-Beuren Syndrome (WBS) deletion, in one individual with an ASD (Subject 3). Using real-time semi-quantitative PCR, I screened a total of 798 individuals with an ASD and 186 healthy controls for the presence of similar abnormalities. No additional cases were identified in either group. Subsequently, I selected 6 genes [Orthodenticle homolog 1 (OTX1), Variable charge, X-linked (VCX), Neuroligin 4, X-linked (NLGN4X), Syntaxin 1A (STX1A), Cytoplasmic linker 2 (CYLN2) and General transcription factor IIi (GTF2i)], based on their function and localization within or in the vicinity of the rearrangements and tested them for association with ASDs. Although there was no evidence for association for any marker or haplotype in most of the genes tested, this was not so for GTF2i. Haplotype transmission disequilibrium testing revealed an increased transmission, from healthy parents to their affected offspring, of the common alleles of one marker and one haplotype in GTF2i (P = 0.0010 and 0.0005, respectively). This gene encodes a brain-expressed transcription factor previously implicated in the mental retardation associated with WBS. Based on these findings, I propose that, although the genomic rearrangements reported herein are not a common cause of ASDs, the GTF2i gene within the WBS critical region is important in the aetiology of autism.

abstract: PhD


title: Three Essays in Empirical Public Economics

contributor:
Beach, Charles
Lehrer, Steven F.
Economics

subject: Public Economics

abstract: Thesis (Ph.D, Economics) -- Queen's University, 2009-11-24 14:06:51.443

abstract: This dissertation explores three questions in empirical public economics: we investigate the impact of social networks on labour market outcomes in the first essay; we explore the determinants of volunteering behaviour and estimate the effect of employment on volunteering in the second essay; and we examine the impact of political and fiscal decentralization on public provision in the third essay. In each case, we provide consistent estimates by utilizing an exogenous source of variation in key economic outcomes introduced by randomized policy experiments in the first two essays and by a natural experiment in the third essay. In the first essay, we find that among social networks, weak ties have a significant effect on labour market outcomes but strong ties do not have. In the second essay, we find that employment has a significant effect on volunteering behaviour, and that the effect varies in different contexts and depends on the precise channels through which the two are connected. In the final essay, we find that decentralization has a big effect on public provision. But we also find that decentralization affects different public goods differently, and that the key to its impact lies in the incentives facing politicians at the local level.

abstract: PhD


title: The Development and Characterization of a Primarily Mineral Calcium Phosphate - Poly(ε-caprolactone) Biocomposite

contributor:
Smith, Reginald W.
Mechanical and Materials Engineering

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subject:
biocomposite
cervical fusion
calcium phosphate
polycaprolactone

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2009-11-24 16:18:16.461

abstract:
Orthopaedic reconstruction often involves the surgical introduction of structural implants that provide for rigid fixation, skeletal stabilization, and bone integration. The high stresses incurred by these implanted devices have historically limited material choices to metallic and select polymeric formulations. While mechanical requirements are achieved, these non-degradable materials do not participate actively in the remodeling of the skeleton and present the possibility of long-term failure or rejection. This is particularly relevant in cervical fusion, an orthopaedic procedure to treat damaged, degenerative or diseased intervertebral discs. A significant improvement on the available synthetic bone replacement/regeneration options for implants to treat these conditions in the cervical spine may be achieved with the development of primarily mineral biocomposites comprised of a bioactive ceramic matrix reinforced with a biodegradable polymer. Such a biocomposite may be engineered to possess the clinically required mechanical properties of a particular application, while maintaining the ability to be remodeled completely by the body. A biocomposite of Si-doped calcium phosphate (Si-CaP) and poly(ε-caprolactone) (PCL) was developed for application as such a synthetic bone material for potential use as a fusion device in the cervical spine.

In this thesis, a method by which high mineral content Si-CaP/PCL biocomposites with interpenetrating matrices of mineral and polymer phases may be prepared will be demonstrated, in addition to the effects of the various preparation parameters on the biocomposite density, porosity and mechanical properties.

This new technique by which dense, primarily ceramic Si-CaP/PCL biocomposites were prepared, allowed for the incorporation of mineral contents ranging between 45-97vol%. Polymer infiltration, accomplished solely by passive capillary uptake over several days, was found to be capable of fully infiltrating the microporosity of the sintered calcium phosphate ceramic. After infiltration, these biocomposite materials demonstrated an increase in compressive strength, flexural strength and Young’s modulus with increasing ceramic content and met design targets for use as a cervical fusion prosthesis. The biocomposite was amenable to shaping and drilling and was found to maintain its strength after 30 days immersion in Earle’s Balanced Salt.

abstract: PhD


title: Situating Charlotte: Reading Politics in Portraits of Belgian Princess Charlotte, Vicereine of Lombardy-Venetia, Empress of Mexico

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subject:
Charlotte of Saxe Coburg Gotha
Historical Portraiture

abstract: Thesis (Ph.D, Art History) -- Queen's University, 2008-11-28

abstract:
The political significance of portraits of Charlotte of Saxe Coburg Gotha (1840-
1927) has been obscured by her historical liminality and by romantic myths that have
prevailed since the late nineteenth century and influenced interpretations of her visual
representations. This thesis reassembles a wide range of images of Charlotte and
analyzes these as sequential representations of an individual participating, across diverse
cultures, in defining episodes of the nineteenth century. Strategies of allegory,
programmatic intertextuality, and revisionism are revealed when these images are read
within their political circumstances of production and complicate the dominance of a few
late, iconic portraits of Charlotte and their entrenched associations. The use of costume,
essential in certain portraits commissioned during Charlotte’s childhood in Belgium, is
revisited in images depicting her during a brief position as Vicereine of Lombardy-
Venetia and in another dating from her role - of equal brevity but indelible historical
resonance - as Empress of Mexico. The significance of dress is explored in relation to
agency and political influence and as demonstrating compliance with, or negotiation of,
gender conventions. Charlotte’s public life was abruptly terminated upon her 1866 return
to Europe by a diagnosis of ‘madness.’ Napoleon III was withdrawing troops supporting
the Mexican Empire and her journey was made seeking to reverse this decision. I
speculate a painting by French artist Edouard Manet allegorically records this episode of
Charlotte’s life and that other factors relating to this episode subsequently influenced the
erasure of her imperial images until their reappearance in the twentieth century.

abstract: PhD


title: Investigating the Effect of Smectic A Temperature Range Variation on De Vries Properties

contributor:
Lemieux, Robert P.
Chemistry

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subject:
Liquid Crystals
de Vries Character

abstract: Thesis (Master, Chemistry) -- Queen's University, 2009-11-30 13:42:44.584

abstract:
Ferroelectric liquid crystals (FLCs) have been investigated as the basis for a new type of liquid crystal display because of their fast switching times. Commercial FLC materials are mixtures consisting of a small amount of chiral dopant in an achiral liquid crystal host with an isotropic-nematic-smectic A-smectic C (INAC) phase sequence, which is required to achieve proper alignment between glass slides with rubbed polyimide alignment layers. However, the layer contraction occurring at the SmA-SmC phase transition on cooling from isotropic liquid is a severe problem that leads to a buckling of the smectic layers and results in zigzag defects that drastically degrade the optical quality of FLC films. To solve this problem, we are focusing on a new class of liquid crystal molecules with minimal or no smectic layer shrinkage at the SmA-SmC transition which is referred to as ‘de Vries-like.’
Previous work in the Lemieux group has shown that combining structural elements promoting SmA and SmC phases in a single molecule increases de Vries-like behavior. Giesselmann et. al. suggest that a correlation exists between the temperature range of the SmA phase and de Vries-like behavior. In the study described herein, two homologous series of molecules with 2-phenylpyrimidine cores with siloxane-terminated side-chain (SmC promoting element) and a chloro-terminated side-chain (SmA promoting element)are synthesized and characterized by polarized optical microscopy, differential scanning calorimetry and small-angle X-ray diffraction (SAXS). The reduction factor R for series 1.13 from 0.36 to 0.46 and for series 1.14 from 0.47 to 0.54. Results show that, although there is some correlation between % layer contraction and SmA temperature range, it can be explained primarily by differences in tilt angle θ. When θ is taken into account in the
R values, there is no correlation.
Another aspect of the study described herein, two siloxane-terminated
2-phenylpyrimidine chiral dopants are synthesized and characterized by polarized optical microscopy, differential scanning calorimetry and small-angle X-ray diffraction (SAXS).

abstract: M.Sc.


title: An Empirical Study for the Impact of Maintenance Activities in Clone Evolution

contributor:
Zou, Ying
Computing

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subject:
Clone Detection
Clone Evolution

abstract: Thesis (Master, Computing) -- Queen's University, 2009-11-25 14:18:05.884

abstract:
Code clones are duplicated code fragments that are copied to re-use functionality and speed up development. However, due to the duplicate nature of code clones, inconsistent updates can lead to bugs in the software system.  Existing research investigates the inconsistent updates through analysis of the updates to code clones and the bug fixes used to fix the inconsistent updates. We extend the work by investigating other factors that affect clone evolution, such as the number of developers.

On two levels of analysis, the method and clone class level, we conduct an empirical study on clone evolution. We analyze the factors affecting bug fixes and co-change (i.e. update cloned methods at the same time) using our new metrics. Our metrics are related to the developers, code complexity, and stages of development. We use these metrics to find ways to improve the maintenance of cloned code. We discover that one way to improve maintenance of code clones is the decrease of code complexity. We find that increased code complexity leads to a decrease in co-change, which can lead to bugs in the software.

We perform our study on 6 applications. To maximize the number of clones detected, we use two existing code clone detection tools: SimScan and Simian. SimScan was used to find clones in 5 of the applications due to its versatility in finding code clones. Simian was used to detect clones due to its reliability to find code clones regardless of language or compilation problems. To analyze and determine the significance of the metrics, we use the R Statistical Toolkit.

abstract: M.Sc.


title: Alasdair MacIntyre's After Virtue After Auschwitz

contributor:
Leighton, Stephen
Philosophy

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subject:
Philosophy
Virtue Ethics

abstract: Thesis (Master, Philosophy) -- Queen's University, 2009-11-25 16:01:42.585

abstract: This thesis explores the concept of moral breakdown in Auschwitz to consider what happens to the virtues under extreme circumstances.  The method of exploration applies Alasdair MacIntyre’s virtue theory to the moral experience of Auschwitz inmates.  The application of his theory to the moral landscape of Auschwitz sheds light on the ability of MacIntyre’s virtue ethical approach to make sense of extreme circumstances in terms of his account of the minimal conditions required for the moral life.  I argue that MacIntyre’s account of narrative moral agency as fundamental to the intelligibility of moral life passes the limit test of Auschwitz experience by showing that the intelligibility of moral life is called into question when the narrative nature of moral agency is seriously interrupted and fragmented.  As such, he offers good conceptual resources for understanding the demoralization Auschwitz inmates faced.  This is so because he emphasizes the manner in which any moral theory must be capable of social embodiment, and he takes seriously the notion that every social situation reflects a set of moral standards that can be articulated theoretically.  This allows MacIntyre to spell out the moral theory embodied in the moral landscape of Auschwitz and to judge it deficient in terms of his conceptual framework of a core conception of the virtues.

abstract: M.A.


title: Constraints and Policy in Education and Public Budget Limits

contributor:
Boadway, Robin W.
Economics

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subject:
Equality of Opportunity
Optimal Taxation
Education Economics
Education Institutions
Redistribution
Debt Limits
Political Agency

abstract: Thesis (Ph.D, Economics) -- Queen's University, 2009-11-25 20:25:29.12

abstract:
This dissertation investigates the impacts of constraints on optimal government policy.  The first two chapters provide a general introduction and review of the literature. Chapters three and four analyze education spending and institutional structure in an economy with informational asymmetries and employment matching frictions. The fifth investigates the impact of politics on government decisions over taxation and spending programs more generally.
Chapter three analyzes the situation where governments can target education funds to specific observable groups (referred to as low and high productivity neighbourhoods/regions). The results suggest that it may be optimal to employ educational transfers, rather than cash transfers amongst individuals, to achieve social welfare objectives.  This is because the former can reduce distortions created by the tax system.  However,  the value of educational spending in mitigating these information frictions may not be that large, and may in fact exacerbate such distortions.  This suggests that an optimal education policy may be more regressive when there is a distortionary tax system in place.  Further, we show that even if ``equalizing opportunities'' is deemed optimal in the static problem, it may not be a reasonable policy goal when we extend the analysis to include dynamics.
Chapter four is joint work with Afrasiab Mirza.  We analyze an economy where heterogeneous individuals are uncertain about their endowments. The education system trades off the desire to capitalize on talent through specific skills training with the need to provide individuals with opportunities to learn about
their career preferences through a broader education. The results consider the implications of various educational institutions for the income distribution and consequently welfare.
Chapter five analyzes the dynamics of public spending, taxation and debt in a political agency model. Choices are made by short-lived politicians who can be only partially controlled through the electoral process. The main focus is to consider the impacts of binding limits on the public budget.  The value of imposing this additional friction depends both on the extent to which politicians' goals deviate from their  constituencies and how effectively the electoral process disciplines them when they misbehave. The results also suggest that the value of such a restriction depends on the fiscal position at the time in which it is imposed.

abstract: PhD


title: Problems on Geometric Graphs with Applications to Wireless Networks

contributor:
Meijer, Henk
Rappaport, David
Computing

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subject:
Wireless Network
Geometric Graph
Computational Geometry
Algorithm
Distributed Algorithm

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2009-11-25 21:04:37.0

abstract:
It is hard to imagine the modern world without wireless communication. Wireless
networks are, however, challenging inasmuch as they are useful. Because of their
complexity, wireless networks have introduced a myriad of new problems into the field of algorithms. To tackle the new computational challenges, specific models have been devised to suit wireless networks. Most remarkably, wireless networks can be modelled as geometric graphs. This allows us to address problems in wireless networks using tools from the fields of graph theory, graph algorithms, and computational geometry.
Our results have applications to routing, coverage detection, data collection, and fault recovery, among other issues in this area.

To be more specific, we investigate three major problems: a geometric approach to
fault recovery; the distributed computation of Voronoi diagrams; and finding Hamiltonian cycles in hexagonal networks. Our geometric approach to fault recovery has been experimentally proved superior to an existing combinatorial approach. The distributed algorithm we propose for computing Voronoi diagrams of networks is the
first non-trivial algorithm that has been proved to perform this task correctly; its efficiency has been demonstrated through simulations. Regarding the Hamiltonian
cycle problem of hexagonal networks, we have advanced this topic by providing conditions for the existence of such a cycle, in addition to new insight on its complexity for
the "solid" hexagonal grid case. Although we present satisfying solutions to several
of the addressed problems, plenty is left to be done. In this regard, we identify a set
of open problems that will be subject of research for years to come.

abstract: PhD


title: Mechanisms of Amiodarone and Desethylamiodarone Cytotoxicity in Human Lung Cells

contributor:
Massey, Thomas E.
Pharmacology and Toxicology

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subject:
Amiodarone
Desethylamiodarone
vitamin E
Renin-angiotensin system

abstract: Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2009-11-26 13:57:09.65

abstract:
Amiodarone (AM) is a potent antidysrhythmic agent which can cause potentially life-threatening pulmonary fibrosis, and N-desethylamiodarone (DEA) is a metabolite of AM that may contribute to the toxicity of AM in vivo.  Recent evidence has implicated the involvement of the renin-angiotensin system (RAS) in the initiation and progression of amiodarone-induced pulmonary toxicity.
In cultured HPL1A human peripheral lung epithelial cells, we found AM to be converted to DEA minimally (< 2%) after 24 h of incubation, indicating that the HPL1A cell culture model can be used to study the effects of AM and DEA independently.  Apoptotic cell death was assessed by annexin-V-FITC (ann-V) staining and by terminal deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate nick-end labeling (TUNEL), while necrotic cell death was determined by propidium iodide (PI) staining.  The percentage of PI positive cells increased over six-fold after 24 h treatment with 20 μM AM (80.8%) compared to control (12.0%), and doubled after 24 h treatment with 3.5 μM DEA (20.4%) compared to control (10.8%).  The percentage of ann-V positive cells decreased from 8.26% (control) to 1.56% following 24 h treatment with 10 μM AM and more than doubled after 24 h incubation with 3.5 μM DEA (22.0%) compared to control (9.86%) (p<0.05).  Treatment for 24 h with 5.0 μM DEA caused the percentage of TUNEL positive cells to increase from 4.21% (control) to 26.7% (p<0.05).  Vitamin E (5 – 20 μM) did not protect against AM or DEA cytotoxicity, as determined by ann-V and PI dual staining.
Angiotensin II (100 pM – 1 μM) alone or in combination with AM or DEA did not alter cytotoxicity.  Furthermore, the angiotensin converting enzyme inhibitor captopril did not protect against AM or DEA cytotoxicity.  In conclusion, in vitro, AM activates primarily necrotic pathways, whereas DEA activates both necrotic and apoptotic pathways, and the RAS does not seem to be involved in AM or DEA cytotoxicity in HPL1A cells.  Multiple mechanisms may contribute to the initiation of lung damage observed clinically, due to actions of both AM and its metabolite DEA.

Keywords:  amiodarone, desethylamiodarone, vitamin E, renin-angiotensin system

abstract: M.Sc.


title: Biomechanically Constrained Ultrasound to Computed Tomography Registration of the Lumbar Spine

contributor:
Abolmaesumi, Purang
Mousavi, Parvin
Computing

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subject:
Ultrasound
Spine
Multimodal Registration
Biomechanical Model

abstract: Thesis (Master, Computing) -- Queen's University, 2009-11-27 13:48:33.288

abstract:
Spinal injections for back-pain management are frequently carried out in hospitals and radiological clinics. Currently, these procedures are performed under fluoroscopy or CT guidance in specialized interventional radiology facilities, and thus incur a major financial burden on the healthcare system. Additionally, the current practice exposes patients and surgeons to X-ray radiation.  The use of US for image guided navigation of the spine would greatly reduce the exposure of both the patient and the physician to ionizing radiation and allow the procedure to be performed outside of a specialized facility.  However, US as the sole guidance modality has its own challenges.  In particular, due to the significant level of occlusion in spinal US images, it can be difficult to accurately identify the appropriate injection site.

Here, a groupwise US to CT registration algorithm for guiding percutaneous spinal interventions is presented. In our registration methodology, each vertebra in CT is treated as a sub-volume and transformed individually. A biomechanical model is used to constrain the displacement of the vertebrae relative to one another. The sub-volumes are then reconstructed into a single volume. In each iteration of registration, an US image is simulated from the reconstructed CT volume and an intensity-based similarity metric with the real US image is calculated. Validation studies are performed on datasets from a lamb cadaver, five patient-based phantoms designed to preserve realistic curvatures of the spine and a sixth patient-based phantom where the curvature of the spine is changed between preoperative and intraoperative imaging.

For datasets where the spine curve between two imaging modalities was artificially perturbed, the proposed methodology was able to register initial misalignments of up to 20 mm with a success rate of 95%. For the phantom with a physical change in the curvature of the spine introduced between the US and CT datasets, the registration success rate was 98.5%. Finally, the registration success rate for the lamb cadaver with soft tissue information was 87%. The results demonstrate that our algorithm robustly registers US and CT datasets of the spine, regardless of a change in the patients pose between preoperative and intraoperative image acquisitions.

abstract: M.Sc.


title: Implementing the Bimolecular Fluorescence Complementation Assay to Study Protein Interactions in the Cell Cycle Checkpoint Response

contributor:
Davey, Scott
Biochemistry

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subject: Rad9

subject: Checkpoint

subject: 9-1-1

subject: TopBP1

abstract: Thesis (Master, Biochemistry) -- Queen's University, 2009-12-17 12:42:06.717

abstract: The genomic integrity of a cell is constantly being pressured by both intrinsic and extrinsic forces.  Cell cycle checkpoints exist to protect the cells by arresting cell cycle progression in response to DNA damage or replication stress. It has been shown that the interaction between the checkpoint proteins Rad9A and TopBP1 is a crucial upstream event required for the ATR-dependent checkpoint response to DNA damage, which can be activated throughout different points in the cell cycle. The Bimolecular Fluorescence Complementation (BiFC) technique has recently emerged as a simple and effective tool for analyzing protein-protein interactions in live cell cultures. By fusing complementary fragments of fluorescent proteins to proteins of interest, one can visualize protein-protein interactions through the formation of a mature fluorophore from these fragments. In the current work, the BiFC assay system was employed to study the interaction between TopBP1 and Rad9A; the human homologue of fission yeast Rad9. BiFC vectors expressing TopBP1, Rad9A, and the Rad9A-S387 mutant were constructed and optimized for transfection in HeLa cells. It was shown that the BiFC fusion protein of Rad9A lacked phosphorylation on its constitutive S387 site, although it retained its upstream damage dependent S272 phosphorylation after IR treatment. BiFC signals could be detected in cells containing the BiFC fusion proteins of Rad9A and TopBP1 using confocal microscopy and flow cytometry techniques. However, the signals could not be distinguished from that of the negative control samples. Our results suggest a possibility that our BiFC fusion proteins of interest interact in a non-specific manner, although further characterization is required to confirm this. The BiFC assay employed in this project must be further optimized to effectively study the interaction between Rad9A and TopBP1, as well as other checkpoint proteins. However, this study has given us great insight into the implementation of this new BiFC technique for studying protein interactions in the context of cell cycle proteins, and the knowledge gained from this study will be invaluable for future work.

abstract: M.Sc.


title: Paradoxical Effects of Immune Cells on the Enteric Nervous System in Intestinal Inflammation

contributor:
Blennerhassett, Michael G.
Physiology

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subject:
Intestinal Inflammation
TNBS-Colitis
Enteric Nervous System
Nitric Oxide

abstract: Thesis (Master, Physiology) -- Queen's University, 2009-11-30 10:09:38.384

abstract:
Inflammatory bowel disease causes structural and functional alterations in the enteric nervous system (ENS). Since the onset of intestinal inflammation involves the activation of resident immune cells as well as rapid influx of infiltrating cells, we proposed that changes in the ENS are a result of the release of toxic inflammatory factors. We hypothesized that early damage to the ENS in inflammation is caused by harmful levels of nitric oxide (NO) generated by the enzyme inducible nitric oxide synthase (iNOS) found in immune cells. This was assessed in the 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-model of colitis in rats. Large increases in infiltrating granulocytes, particularly neutrophils and blood-derived monocytes were found in the muscularis layers adjacent to the ENS. A rapid increase in iNOS immunoreactivity in the muscularis regions during early stages of inflammation (6 – 24 hr) was observed. Whether high NO levels generated by chemical donors could be toxic to neurons was tested in a co-culture model of myenteric neurons, smooth muscle and glia enzymatically isolated from neonatal rats. Exposure of co-cultures to NO for 48 hr resulted in significant, concentration dependent decrease in neuron survival.
We then developed a model that permitted the direct study of immune cell interactions with myenteric neurons. Myenteric neurons were co-cultured with activated peritoneal immune cells that expressed iNOS and generated high NO levels (49 + 6.2µM) for 48 hr. This caused significant neuronal death, reducing neuron number by 19 + 5%, and disruption of axons. Pre-treatment of immune cells with a selective iNOS-inhibitor, L-NIL resulted in neuron numbers that were not significantly different from control (96 + 2%) suggesting that NO played a central role in mediating the damaging effects of immune cells. Lastly, when direct contact between immune cells and neurons was prevented in the previous experiment through use of trans-wells, unanticipated neurotrophic effects were observed. Increased axon outgrowth (282 + 57%) was detected in addition to loss of the neurotoxic effects in spite of similar experimental conditions. We concluded that proximity and contact plays an important role in determining the nature of immune cell mediated alterations in enteric neurons.

abstract: M.Sc.


title: The Coordination of Multi-Joint Reaching Movements: A Developmental Profile

contributor:
Pelland, Lucie
Rehabilitation Science

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subject:
Rehabilitation
Sensory-Motor Coordination
Paediatrics
Multi-Joint Reaching

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2009-11-30 11:29:28.718

abstract:
The study of visually-guided reaching has been a meaningful tool to investigate sensory-motor coordination in typical development and different clinical paediatric populations. The aim of this study was to characterize the development of multi-joint reaching behaviour in children and youth, from 5 to 16 years of age, allowing us to capture changes that may occur into adolescence.
Participants were 68 able-bodied children and youth, with no history of developmental, educational or social problems. A stratified recruitment strategy was used to adequately represent five age groups: I (5-6 years), II (7-8 years), III (9-10 years), IV (11-13 years) and V (14-16 years). A center-out reaching task was used as it allowed us to measure effects of limb mechanics during reaching. Different patterns of inter-segmental motions at the shoulder and elbow joints were needed to reach the different targets: flexion at both joints, extension at both joints, and a mixed-coordination pattern.  Children were asked to reach quickly and accurately to 8 targets located at 45 degree intervals around the perimeter of a circle with a 6 cm radius.
The development of reaching was described using non-parametric statistics. The global features of path length and total movement decreased as a function of increasing age, with less variability observed in older participants (p<0.05). This increased accuracy was explained by a significant reduction (p<0.05) in distance and direction error of the first movement component of the reach, indicative of the increasing ability of children to accurately plan movements based on an internal representation of the limb. These older children were also able to respond to the visual target more quickly (p<0.05). In general, initial direction errors and total movement time increased from a minimum for the 2-joint flexion coordination to a maximum for the mixed-coordination pattern. The magnitude of error, however, decreased as a function of age (p<0.05), and in particular for the mixed-coordination pattern (p<0.01).
This center-out task is therefore considered to be responsive to observe effects of development and limb mechanics on performance. The established normative data set will provide a reference for the measures of performance in children with neurodevelopmental disorders.

abstract: M.Sc.


title: Testing Shneidman's Theory of Suicide: Psychache as a Prospective Predictor of Suicidality and Comparison with Hopelessness

contributor:
Holden, Ronald R.
Psychology

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subject:
suicide
psychological pain

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-11-30 13:33:54.267

abstract: Shneidman (1993) has theorized that psychache  (i.e., intolerable psychological pain) is the key cause of suicide, and accounts for the effect of all other psychological factors. Two studies are presented that test Shneidman’s theory, and compare the influence of psychache on suicidality relative to that of hopelessness. In the first study, a causal hypothesis was examined using a longitudinal design. Undergraduate students (N = 588) completed measures of psychache, hopelessness, and suicide ideation at two time points four months apart. Results supported the hypothesis that psychache has a causal role in suicidality, as change in suicide ideation was predicted by change in psychache. However, the hypothesis that psychache would fully mediate the effect of hopelessness was not supported, as only a small and partial mediation effect was evidenced, and change in hopelessness also contributed unique variance to the prediction of suicide ideation. In a second study, the hypotheses that psychache is necessary and sufficient for suicide were examined. Undergraduate students (N = 1,333) were prescreened for high and low levels of psychache and hopelessness, and those who met cutoff criteria (N = 184) were selected to make up four groups with combinations of these constructs. Groups were compared with respect to various measures of suicide ideation, motivations, and behaviours using one-way multivariate analyses of variance. In general, dependent measures significantly differed by level of psychache, but not by level of hopelessness. This pattern of group differences supported the hypothesis that psychache is necessary for suicide. However, the claim that psychache is sufficient was not consistently supported, as some suicide criteria were significantly elevated only for groups exhibiting high levels of both psychache and hopelessness. Taken together, the results of this dissertation provide strong support for the key role of psychache in suicide and its parity with hopelessness as a statistical predictor of suicidality. These findings improve understanding of the suicidal state of mind, and have important implications for clinical practice.

abstract: PhD


title: HIV counselling and testing among Kenyan male youth aged 13-15 years: The Theory of Planned Behaviour Applied

contributor:
Fergus, Stevenson
Kinesiology and Health Studies

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subject:
HIV
Voluntary counselling and testing
Kenya
Theory of planned behaviour

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-12-04 10:06:25.104

abstract: An understanding of individual cognitions that influence both behavioural intentions and the enactment of actual behaviours is provided by the conceptual model of the Theory of Planned Behaviour (TPB). This study used the Theory of Planned Behaviour, with the added variable of perceived risk, to predict Kenyan students’ intention to use HIV voluntary counselling and testing (VCT) centres within the country. We conducted a survey questionnaire with 200 students, aged 13-15 years, within high schools in the Nairobi and Nakuru districts in May 2009. Chi-squared analysis showed no relationships between age, school, school level, knowledge of a VCT centre, or past sexual experience with intention to uptake HIV counselling and testing. Pearson product-moment analysis revealed a small positive correlation between attitude and subjective norm and a medium negative correlation between perceived behavioural control and perceived risk. One-way analysis of variance showed a relationship between perceived behavioural control and intention. Results of block entry logistic regression analysis indicate that perceived behavioural control and perceived risk were significant predictors of intention to use VCT services in the TPB model. The present study suggests that Kenyan teens’ perceived ease/difficulty in performing a specific behaviour is the most influential aspect in predicting their subsequent intention to carry through the behaviour. A theory-based intervention program should focus on reducing practical barriers related to the use of VCT services.

abstract: M.Sc.


title: Evaluation of a Pilot Workplace Health Promotion Intervention Targeting Employees' Health Behaviours: the Motiv8 Workplace Series

contributor:
O'Connor, Kate
Fergus, Stevenson
Kinesiology and Health Studies

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subject: Evaluation Intervention

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-12-04 10:34:13.947

abstract:
Background: The workplace provides a setting to offer health promotion interventions to a large proportion of adults.  Given the high rates of obesity and chronic disease among this population, it is of public health importance to provide and evaluate these interventions.
Objectives: The purpose of this study was to pilot an evaluation of the Motiv8 Workplace Series (MWS) using the RE-AIM framework.  The objectives of this study were 1) to provide measures of adoption, reach, and implementation of the MWS, 2) to provide estimates of the effectiveness of the MWS in changing physical activity and healthy eating behaviours, and in changing theoretical variables from the social cognitive theory and the health action process approach, and 3) to use the data to investigate the role of theoretical variables as mediators in changing these health behaviours.
Methods: This pilot study used a quasi-experimental, non-equivalent control group design.  The study population consisted of employees aged 18 and older, living in Kingston and surrounding area.  The study investigated 1) the participation rate and representativeness of participating workplaces (adoption), 2) the participation rate and representativeness of employees participating in the MWS (reach), 3) the extent to which the MWS was implemented as intended (implementation), and 4) the impact of the MWS on participants through measures of behavioural outcomes (effectiveness).  A questionnaire was administered at baseline and 1-week follow-up.
Results: Objective 1.  The participation rate was low among workplaces.  Participating and non-participating workplaces were similar with respect to all characteristics except past public health programming.  There was also a low rate of participation among employees.  Participants did not appear to be representative of all workplace employees.  Objective 2.  There was a significant difference in healthy eating (p<.05), but no significant difference in physical activity (p>.05) between participants in the intervention and comparison groups at follow-up.  Objective 3.  There was evidence for action planning as a partial mediator of the relationship between the intervention and healthy eating.
Conclusions: The preliminary findings from this evaluation suggest that the MWS had moderately low reach and adoption, good program implementation, and was effective at changing eating behaviour among employed adults.

abstract: M.Sc.


title: Creating and Imaging Surface Acoustic Waves on GaAs

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subject:
surface acoustic waves
sagnac interferometer
interdigital transducers

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-12-08 12:28:35.962

abstract:
The versatility of surface acoustic wave (SAW) devices stems from the accessibility of the propagation path to modification and detection. This has led to the integration of SAWs in a variety of novel fields, including quantum information processing.

The development of technologically competitive devices requires the use of gigahertz frequency SAWs. This thesis develops fabrication processes for high frequency interdigital transducers on gallium arsenide. Optically lithography was used to create linear and stepped transducers, with a minimum feature size of 2 um, that were driven at their fifth harmonic. The highest frequency achieved was 1435 MHz, but the power absorbed was less than 3% and insertion losses were greater than -80 dB. Further improvements in the design and fabrication are required if optically fabricated transducers are to be an alternative to transducers with narrower finger widths. Electron-beam lithography techniques were developed and used to create transducers with finger widths of 500 and 400 nm, with fundamental resonance frequencies of 1387 and 1744 MHz, respectively. The power absorbed was 3 to 6% with insertion losses greater than -45 dB. The performance characteristics can be improved by the removal of residual resist on the surface of the transducer.

An indispensable tool for the characterization of one-port transducers is an all optical probe to measure the displacement field of a SAW. This work details the design and construction of a scanning Sagnac interferometer, that is capable of measuring the outward displacement of a surface. The spatial resolution of the interferometer was 2.4 +/- 0.2 um and the displacement sensitivity was determined to be 4 +/- 1 pm. The instrument was used to map the SAW displacement field from a 358 MHz transducer, with results showing the resonant cavity behaviour of the fingers due to Bragg reflections. It also allowed for the direct detection of the SAW amplitude as a function of the driving frequency of the transducer. The results showed good agreement with the related S21 scattering parameter. Lastly, the interferometer was used to image the attenuated propagation of SAWs through a phononic crystal. Results showed good agreement with theoretical simulations.

abstract: M.Sc.


title: William Lyon Mackenzie King; A Very Double Life?

contributor:
Van Die, Marguerite
History

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subject:
King
Spiritualism
Canadian
History
Mackenzie
Prime Minister

abstract: Thesis (Master, History) -- Queen's University, 2009-12-06 20:38:59.97

abstract:
This thesis examines the interest in spiritualism of Canada’s tenth Prime Minister, William Lyon Mackenzie King. By placing King’s engagement with spiritualism within the context of recent historiography on spiritualism as a progressive form of religion in the late nineteenth and early twentieth century, this research demonstrates that spiritualism was not a pseudo-religion or parlour game but rather, a religious practice meaningful to King both as a component of his faith and his intellectual pursuits.

Within the context of this thesis, spiritualism is treated as a lived religion. Based on the research of Robert Orsi and David D. Hall, whose contention is that religion comes into existence only in a dynamic relationship with the realities of everyday life, particular attention is paid to those parts of King’s world that serve as the building blocks for his first encounters with spiritualism.

This research demonstrates that while King remained skeptical of spiritualist claims until later in his life, his eventual acceptance of spiritualism was the result of several factors. Though the deaths within his immediate family in the early 1900s served as a catalyst for King’s desire to seek spirit contact, it was his reading and involvement in social Christianity as early as 1891, when he began his studies at the University of Toronto that provided the scaffolding for King’s incorporation of spiritualism into his later life. It is argued that, ultimately, King’s goals remained consistent throughout his personal evolution: to lead a Christian life in service to the less fortunate and to the people of Canada.

abstract: M.A.


title: Axotomized Spinal Commissural Interneurons of the Adult Feline:  A study of axonal growth from dendrites and cut axons

contributor:
Rose, Ken P.
Physiology

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subject:
Spinal Cord Injury
Commissural Interneuron
Axonal Regeneration
Growth Cone
GAP-43
MAP2a/b
Chondroitin Sulfate Proteoglycans
Electrophysiology
Neuroanatomy
Synaptophysin
Feline

abstract: Thesis (Ph.D, Physiology) -- Queen's University, 2009-12-07 11:21:47.036

abstract:
Acquiring knowledge of the morphological, molecular, and functional changes that occur to neurons following axotomy is a key step for a comprehensive understanding of the nervous system and how it reacts to injury. Propriospinal commissural interneurons (PCIs or CINs) are a class of neuron with axons that project through the ventral commissure to the contralateral spinal cord. My goal was to examine the morphological, molecular, and functional changes that occur to adult feline PCIs following a proximal axotomy.
	We first determined whether proximally axotomized PCIs develop de novo axons from their dendrites. C3 PCIs were proximally axotomized and several weeks later we stained PCIs and prepared the tissue for histological evaluation. Two primary classes of axotomized PCI were identified: those with a very short axon (called permanently axotomized) and those with an axon that projected across the injury site. Permanently axotomized PCIs had processes with morphological features typical of axons that emerged from their distal dendrites. These axonal processes of the distal dendrites also had GAP-43 (an axonal marker) and lacked MAP2a/b (a dendritic marker). We concluded that permanently axotomized PCIs develop de novo axons from distal dendrites.
	We then determined whether the axons that crossed the lesion site were representative of spontaneous functional regeneration. First, we showed that PCI axons regenerate through an environment that is typically highly inhibitory to regenerating axons. Second, we established that the regenerated axons conduct action potentials. Finally, we found that regenerated PCI axons form functional synaptic connections with neurons in the contralateral spinal cord. Collectively, these data indicated that spinal interneurons are capable of spontaneous functional regeneration through an injured spinal cord.
	PCI growth cones are complex and unlike growth cones previously described in the literature. The final study of the thesis examines the morphologies of PCI growth cones within spinal cord injury sites. We found that PCI growth cones have a wide range of morphologies that is independent of their location within the lesion site.
	 Taken together, these data indicate that PCIs have a remarkable capacity for axonal elongation and contribute to remodelling of spinal circuitry following spinal injury.

abstract: PhD


title: Studies of Highly Polar Atomic and Molecular Systems: Quantum Dynamics and the Route to Experimental Investigations

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subject:
Atomic Physics
Molecular Physics
Adiabatic Quantum Mechanics
lithium
Stark Effect
Rydberg states/systems
Ion-pair Formation
Colliding Atoms

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-12-09 16:49:41.184

abstract:
Theoretical investigation of the dynamics of adiabatic quantum mechanics in two different, highly polar systems has been made. The systems were chosen for their
fundamental scientific interest, as they represent atoms and molecules with exaggerated properties, as well as ease of experimental study as such highly polar systems are easier to manipulate using readily-available electric fields. A model two-level system is used to derive one approach for maximizing the probability of adiabatic passage through an avoided crossing and this is compared with the classic Landau-Zener result, and the commonly encountered spin-flip problem of a particle with spin located in a rotating magnetic field. This approach is applied to the avoided crossing between the n = 13, n1 − n2 = 11 (dipole moment of 532 D) and the n = 14, n1 − n2 = −12 (dipole moment of -657 D) highly polar Stark states of the lithium atom at 447 kV/m. Ion-pair formation from two neutral lithium atoms, one in the 2s ground state and the other in an excited state, is also investigated. The cross section σ(v) for free ion-pairs is calculated for the initial colliding pairs of atomic states located below the ion-pair threshold. Li(2s) + Li(3d) is seen to possess the largest cross section (σ(v0) = 569.2 a.u.) at its threshold velocity. The implications of this for bound ion-pair, i.e. heavy Rydberg system, production are briefly discussed. Furthermore, experimental progress towards the production of these atomic and molecular systems from a beam of lithium is presented.

abstract: M.Sc.


title: Canada, the United States and the Command and Control of Air Forces for Continental Air Defence from Ogdensburg to NORAD, 1940-1957

contributor:
English, Allan
History

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subject:
History Canada-U.S. Relations
Air Force Command and Control

abstract: Thesis (Ph.D, History) -- Queen's University, 2009-12-12 17:33:33.335

abstract: This dissertation examines the evolution of the bilateral Canadian-American continental air defence operational-level command and control relationship from the 1940 Ogdensburg Agreement to the establishment of the North American Air Defence Command (NORAD) in 1957.  It takes a functional approach, focusing on the efforts of Canadian air force officers in conjunction with their American counterparts to develop efficient command and control arrangements to ensure effective air defence of North America while at the same time safeguarding Canadian sovereignty.  It explores the evolution of certain command and control principles such as cooperation, unity of command, operational command, and operational control, and argues that because Canada was able to avoid having its air defence forces come under American command, Canadian sovereignty was assured.  It also demonstrates that the Canada-U.S. bilateral continental air defence command and control relationship had its origins in Canadian, American, and British joint command and control culture and practice.  Canadian steadfastness, along with compromise and accommodation between the two North American nations, operational and doctrinal factors, and also cordial professional working relationships and personalities, all played important roles in the evolution of this command and control relationship from the “cooperation-unity of command” paradigm of the Second World War towards “operational control” in an air defence context throughout the early Cold War.  This paradigm shift culminated in 1957 with the integration and centralization of combined air defences under an overall NORAD commander exercising operational control.  The thesis also demonstrates that by taking an active role in Canada-U.S. command and control arrangements, Canada was able to avoid a negative “defence against help” situation with the United States and ensure that it secured a proverbial “piece of the action” in the bilateral North American continental air defence mission.  Moreover, through this active functional approach, Canadian officers were able to safeguard Canadian sovereignty and at the same time perform an effective and important operational role in the combined efforts with the United States to defend the continent from aerial attack.  This dissertation therefore makes an important contribution to the study of command and control and the history of North American continental defence.

abstract: PhD


title: Human exposure to mercury and other elements in Eastern China

contributor:
Campbell, Linda M.
Aronson, Kristan J.
Environmental Studies

subject:
total mercury
human hair
fish consumption
female
eastern China

abstract: Thesis (Master, Environmental Studies) -- Queen's University, 2009-12-14 11:52:06.906

abstract:
Mercury contamination is a global issue due to its neurotoxicity, and China is not an exception due to its increasing industrialization. Fish is of the most concern, in respect to human exposure to mercury, because fish accumulates methylmercury through food chain in aquatic systems. The province of Zhejiang is renowned for its cuisine that incorporates freshwater fish. Qiandao Lake, in Zheijang, was the site of a case study examining the link between the total mercury (THg) concentration in hair samples and fish consumption. A questionnaire survey and hair sampling were carried out on women of childbearing age (17-46 years) from a fishing town by Qiandao Lake. The average hair THg concentration was 0.76±0.51μg/g dw. The most-frequently consumed species included four species of carp (golden, bighead, silver and predatory) and the Mongolian redfin. Hair THg concentrations accumulated rapidly during younger years, reaching a plateau around age 25, implying that the hair mercury concentrations in adult females >25 years can be interpreted by environmental exposure. Hair THg concentrations were positively correlated both with the frequency and the average weekly amount of fish consumption. This indicates that fish consumption is an important contributor to hair mercury concentrations in the absence of occupational or environmental mercury sources. A positive correlation between selenium and mercury in hair samples was also observed, suggesting a possible antagonistic relationship. This is the first study to look at mercury exposure in an eastern China community dependent on freshwater fish.
This study also compared element trends (Mg, Ca, Cr, Mn, Cu, Zn, As, Se, Pb) in hair samples from three groups: 50 residents by Qiandao Lake (QD), 17 people from Fudan University, China (FU), and 20 people from Queen’s University, Canada (KI). Trends of mean Mg, Cu, Ca, As concentrations among groups are the same (KI>FU>QD). Mn, Cr, and Hg share the same trends of QD>FU>KI. Se concentrations follow the trend of QD>KI>FU. Strong correlations between Ca and Mg were observed within each group. Relationships between Se and Hg are clear in QD but not in FU and KI, probably due to the different dietary proportion of fish.

abstract: The data within my thesis are potentially sensitive, and touch on controversial issues in China.

abstract: M.E.S.


title: Evaluation of Homing and Functions of Uterine Natural Killer Cells

contributor:
Croy, B. Anne
Microbiology and Immunology

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subject:
Natural Killer Cells
Pregnancy

abstract: Thesis (Master, Microbiology & Immunology) -- Queen's University, 2009-12-15 11:33:37.11

abstract: Uterine Natural Killer cells are the major lymphocyte population in the pregnant uterus in early gestation; outnumbering both T and B cells. The numerical expansion of uterine Natural Killer cells is thought to result from the expansion of preexisting progenitor cells resident to the uterus, recruitment of Natural Killer cells from the circulation, or a combination of both pathways. Uterine Natural Killer cells are capable of cytotoxic killing and express receptors that can recognize foreign paternal antigens. Therefore, it has been argued that uterine Natural Killer cell activation can lead to killing of fetal cells and abortion. However, fetal rejection by uterine Natural Killer cells does not occur in normal pregnancies and other functions for uterine Natural Killer cells have been proposed. These include: the regulation of maternal blood supply responsible for providing oxygen to the fetus, regulation of maternal blood pressure and, in species with invasive placentation, regulation of decidualization, the process of endometrial cell expansion and transformation during the menstrual cycle and during pregnancy. These cell functions juxtapose the concept that uterine Natural Killer cell activation is harmful to the fetus and offer a new perspective that uterine Natural Killer cells regulate functions unrelated to traditional transplantation immunology. In this dissertation, work is presented showing that uterine Natural Killer cells express molecules which regulate blood pressure and decidualization. Also presented are data supporting the hypothesis that the numerical increase of uterine Natural Killer cells is due to the recruitment of Natural Killer cells from the blood. These results support roles for uterine Natural Killer cells other than cytotoxic killing and advance the understanding of uterine Natural Killer cells as dynamic players that support pregnancy-associated biological processes unrelated to traditional understandings of immune surveillance.

abstract: M.Sc.


title: Inclusion of English Language Learners in a Mainstream Classroom: A Case Study of the Beliefs and Practices of One Elementary Teacher

contributor:
Colgan, Lynda
Education

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subject:
English language learners
Inclusive Instructional Practices

abstract: Thesis (Master, Education) -- Queen's University, 2009-12-16 12:45:04.765

abstract:
The purpose of this study was to describe the ways in which one elementary teacher included English language learners (ELLs) in her mainstream classroom. A case study design was chosen to obtain an in-depth understanding of this teacher’s beliefs and practices about ELLs and their inclusion. Descriptive data were collected from teacher interviews, classroom observations, and
various artefacts. Data from these three sources were found to be highly consistent, indicating a close relationship between the teacher’s beliefs and practices.
Two main themes emerged relating to the teacher’s ways of supporting and including young ELLs. The first theme was concerned with the teacher’s beliefs in and employment of broad-based instructional strategies such as differentiating instruction and assessment; emphasizing engagement
through the use of a variety of meaningful activities and materials; focusing on oral language; stressing problem solving and cooperative learning; and encouraging students to take the lead. While
the literature endorsed these general practices, it also stressed the need for teachers to address ELLs’ distinct language and cultural needs.
Appreciating and incorporating diversity to facilitate ELLs’ inclusion was the second theme. Here, the data primarily came from interviews with the teacher who reported the value of exposing children to diversity and examining one’s and others’ biases, as well as utilizing practices that integrate the cultural knowledge of various groups and involve parents of diverse linguistic/cultural backgrounds. An analysis of these data found that many of the teacher’s approaches to incorporating diversity were integral to her program and addressed diversity from a critical standpoint. It was in this way that the findings connected to Dei et al.’s (2000) work–a key component of the study’s theoretical framework.
Upon examining the data through the lenses of various theoretical constructs, one main
concern regarding this teacher’s views and practices was raised throughout. Although the teacher appeared to recognize the value of students maintaining their home languages, there was little
evidence of her promoting first language usage in the classroom. Ramifications of this omission were discussed, pointing to the need for further research to uncover some of the concerns educators may have about supporting ELLs’ first languages in the classroom.

abstract: M.Ed.


title: State space grids: First application of a novel methodology to examine coach-athlete interactions in competitive youth sport

contributor:
Côté, Jean
Deakin, Janice
Kinesiology and Health Studies

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subject:
Coaching
Youth Sport
Dynamic Systems
State Space Grids
Behaviour Observation
Coach-Athlete Interaction

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-12-16 14:46:55.016

abstract: The purpose of this study was to compare the coach-athlete interaction structures of two competitive youth synchronized swimming teams, one more successful with regard to athletes’ performance and personal development than the other. This comparison was conducted through the first application of state space grid (SSG) observational methodology (Hollenstein, 2007; Lewis, Lamey, & Douglas, 1999) in field-based sport psychology research. Both teams (two head coaches and 17 athletes in total) were observed over multiple training sessions. Both coach and athlete behaviour was coded continuously for the duration of each training session. Measures of coach athlete interaction structure, based on dynamic systems concepts, were derived from these coded behaviours and compared between teams. Results revealed significant differences between the two teams on measures of interaction variability, behavioural content patterns, and the sequencing of coach behaviours. The more successful team was characterized by less variable, more patterned interactions between coaches and athletes. This patterning took the form of more individualized technical and positive reinforcement feedback information and significantly less use of negative feedback by the head coach, interspersed with substantial periods of silent observation. The athletes of the more successful team more actively acknowledged the receipt of this feedback from their coach. The sequencing of coach behaviours was more patterned for the coach of the more successful team, with heavy emphasis on the pairing of technical correction and positive reinforcement statements. The findings suggest that a respectful, deliberate pattern of coach-athlete interaction may be associated with youth sport environments producing more positive performance and personal development outcomes for athletes.

abstract: M.A.


title: Characterization of Vascular Calcification in a Rodent Model of Chronic Kidney Disease

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

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subject:
Chronic Kidney Disease
Vascular Calcification
Adenine Diet
Rats

abstract: Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2009-12-16 15:10:49.384

abstract: Chronic kidney disease (CKD) is a worldwide health problem with rising incidence and high cardiovascular mortality.  CKD compromises cardiovascular function, in part, characterized by vascular calcification (VC), elevated pulse wave velocity (PWV) and pulse pressure (PP). Through manipulation of dietary adenine, we produced a model characterized by graded severity of CKD, VC and hyperphosphatemia.  To our knowledge, we are the first to explore the relationship between aortic calcium content and changes in circulatory function in rodents with CKD.  Fourteen-week old Sprague-Dawley rats received a diet containing an adenine concentration (0.25-0.75%) plus high-normal dietary phosphate (1%), for up to 10 weeks. Circulatory changes were determined by arterial radiotelemetry (n=6) and by assessment of aortic pulse wave velocity (PWV, n=32).  VC was assessed using the calcium-O-cresophthalein-complexone assay. At sacrifice, kidney function (creatinine (µmol/L)) was worst in the group with VC (251.3±60.2 µmol/L), compared to non-calcifying CKD (200.3±68.8 µmol/L) or control (50.0±16.2 µmol/L).  PWV (cm/s) adjusted for blood pressure (BP) was markedly elevated in animals with VC (3.23±0.33 log(cm/s)) versus non-calcifying CKD (2.85± 0.12 log(cm/s)) or control (2.96±0.08 log(cm/s)). Arterial pressure radiotelemetry revealed that there was an increase in pulse pressure (38±4.7 mmHg to 58 ±15.2 mmHg) during the development of VC. Systolic pressure remained relatively stable throughout (129±8.7 mmHg), diastolic pressure fell during weeks 9 and 10 of the study (91±6.0 mmHg down to 74±9.1 mmHg), a fall that almost fully accounted for the changes in pulse pressure. The calcifying CKD animals also exhibited left ventricular hypertrophy (LVH) compared to CKD or control animals (2.32±0.3 vs 2.03±0.2, 1.80±0.1 g/kg respectively). Manipulating dietary adenine produces a graded severity of CKD with calcification which impact circulatory changes (PP and PWV).  These altered circulatory functions are likely to be key factors in the enhanced LVH.  This model appears to be a useful for the study of CKD-associated VC.

abstract: M.Sc.


title: Restoration or Retribution: An Empirical Examination of the Recidvistic Patterns of a Group of Young Offenders from New York City

contributor:
Kay, Fiona
Sociology

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subject:
Recidivism
Young Offenders
Restorative Justice
Differential Association Theory
Deterrence Theory
Reintegrative Shaming Theory
Life Course Theory
Incarceration

abstract: Thesis (Master, Sociology) -- Queen's University, 2009-12-16 15:53:46.514

abstract:
This study uses a data set on adolescent offending, originally collected by a team of researchers at the Vera Institute of Justice in New York City, to critically examine the role of incarceration in criminal rehabilitation. A theoretical explanation of recidivism is constructed using four criminological theories: life course theory (Sampson & Laub 1993), differential association theory (Sutherland 1939), deterrence theory, and reintegrative shaming theory (Braithwaite 1989). This thesis uses these theories to investigate societal factors that may contribute to young offenders’ recidivism (versus successful rehabilitation). It is argued that youths who: (1) come from unconventional family environments, (2) possess deviant peer associations, (3) receive incarceration as punishment, and (4) undergo a stigmatizing shaming process are more likely to recidivate. The combination of these factors is also expected to be intensified during incarceration.
An empirical examination of the effects of these factors on recidivism supports the main hypotheses advanced. Although conventional family environments and deviant peer associations are successful in determining first-time offending, results from this study suggest that these are inadequate as predictors of recidivism. Conversely, an extension of Braithwaite’s (1989) reintegrative shaming concept was found to be a strong predictor of subsequent offending. Medium sentence lengths in prison were associated with increased risk to recidivate. Most importantly, the results gathered some support for restorative justice approaches to criminal rehabilitation. Future considerations for recidivism research are explored.

abstract: M.A.


title: The Economic Consequences of Delay in Radiotherapy: An Example in Early Breast Cancer

contributor:
Johnson, Ana
Community Health and Epidemiology

subject:
Health Economics
Health Services and Policy
Radiotherapy
Waiting

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2009-12-16 16:24:46.102

abstract:
Waiting times for cancer radiotherapy have been a concern in Ontario for the past 20 years. A recent review of the clinical trials literature shows that waiting is associated with an increased risk of recurrence. Recurrence and the downstream effects thereof (metastatic disease, death) are expensive to treat. If waiting times can be reduced, the health care system could experience a reduced level of expenditure on recurrence. The magnitude and nature of such reduced expenditures is not known in the scientific literature.
This study proposed and described a methodology for estimating the net benefit of reduced waiting for radiotherapy. A cost-benefit analysis was chosen, in which costs were measured as the value of resources required to increase the capacity of a cancer centre, and benefits were measured as the value of averted recurrence, metastatic disease and death due to waiting. The association between increased capacity and reduced waiting was explored in a computer simulation model. Benefits were calculated using a Markov chain model (a mathematical model that simulates patient movement between different health states based on underlying probabilities). Costs and benefits for various lengths of waiting were combined into a summary measure: the Incremental Net Present Value of increasing capacity in a cancer centre.
A simplified population of postmenopausal (55 years and older) early breast cancer patients who receive adjuvant radiotherapy after breast-conserving surgery was used to illustrate this methodology. Accordingly, a hypothetical example in which a cancer centre treating these breast cancer patients only was presented to illustrate the methodology developed here. Markov modeling was used to compute averted treatment costs due to a decrease in waiting for this population. The costs of operating a cancer centre were calculated based on actual operations data from the Cancer Centre of Southeastern Ontario.
This work provides a useful framework upon which subsequent investigations of this type can be built. Furthermore, this study modernizes the scientific literature regarding the medical care costs of local recurrence. It is our hope that the method proposed herein will be used in subsequent explorations of the issue of the economics of waiting.

abstract: M.Sc.


title: Investor Perceived Earnings Quality and Disclosure of Internal Control Weaknesses

contributor:
Thornton, B. Daniel
Management

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subject:
Perceived Earnings Quality
Sarbanes Oxley Act
Internal Control Material Weakness
E-Loading
SOX 302
SOX 404

abstract: Thesis (Ph.D, Management) -- Queen's University, 2009-12-17 11:41:11.323

abstract: This study investigates whether disclosures of material weaknesses in a firm’s internal control over financial reporting are associated with lower investor perceived earnings quality. I measure investor perceived earnings quality by a market returns based representation of earnings quality called e-loading developed by Ecker et al. (2006). My empirical tests use sample firms that disclosed at least one material weakness from August 2002 to October 2005. The cross-sectional univariate analysis shows that firms disclosing internal control material weaknesses have lower investor perceived earnings quality than matched firms that disclose no internal control problems. However, further cross-sectional multivariate regression analysis reveals that after controlling for firm characteristics, only disclosures of company-level material weaknesses have an incremental impact on investor perceived earnings quality, while disclosures of the less pervasive account-specific material weaknesses do not have a measurable effect on perceived earnings quality. From intertemporal within-firm analysis, I find no evidence that firms experienced a change in their perceived earnings quality after their first disclosure of internal control material weaknesses as per SOX 302 or 404. In contrast, I find that firms experienced an increase in perceived earnings quality after they received their first unqualified SOX 404 audit report indicating remediation of previously disclosed material weaknesses. This suggests that, although investors did not find the initial SOX disclosures of internal control weaknesses to be incrementally informative, the legislation motivated firms to remediate weak controls; moreover, the SOX-induced improvement in weak internal controls enhanced investors’ perception of the offending firms’ financial reporting quality.

abstract: PhD


title: Behaviour of Fibre Reinforced Polymer Confined Reinforced Concrete Columns Under Fire Condition

contributor:
Bisby, Luke
Green, Mark F.
Civil Engineering

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subject: Fire Concrete FRP

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-12-17 14:11:27.931

abstract:
In recent years, fibre reinforced polymer (FRP) materials have demonstrated enormous
potential as materials for repairing and retrofitting concrete bridges that have deteriorated from factors such as electro-chemical corrosion and increased load requirements. However, concerns associated with fire remain an obstacle to applications of FRP materials in buildings and parking
garages due to FRP’s sensitivity to high temperatures as compared with other structural materials
and to limited knowledge on their thermal and mechanical behaviour in fire. This thesis presents
results from an ongoing study on the fire performance of FRP materials, fire insulation materials
and systems, and FRP wrapped reinforced concrete columns. The overall goal of the study is to
understand the fire behaviour of FRP materials and FRP strengthened concrete columns and
ultimately, provide rational fire safety design recommendations and guidelines for FRP
strengthened concrete columns.
A combined experimental and numerical investigation was conducted to achieve the
goals of this research study. The experimental work consisted of both small-scale FRP material
testing at elevated temperatures and full-scale fire tests on FRP strengthened columns. A
numerical model was developed to simulate the behaviour of unwrapped reinforced concrete and
FRP strengthened reinforced concrete square or rectangular columns in fire. After validating the
numerical model against test data available in literature, it was determined that the numerical
model can be used to analyze the behaviour of concrete axial compressive members in fire.
Results from this study also demonstrated that although FRP materials experience considerable
loss of their mechanical and bond properties at temperatures somewhat below the glass transition
temperature of the resin matrix, externally-bonded FRP can be used in strengthening concrete
structural members in buildings, if appropriate supplemental fire protection system is provided
over the FRP strengthening system.

abstract: PhD


title: Direct Numerical Simulation of Compressible and Incompressible Wall Bounded Turbulent Flows with Pressure Gradients

contributor:
Pollard, Andrew
Mechanical and Materials Engineering

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subject: Direct numerical simulation

subject: Discontinuous Galerkin method

subject: Wall bounded Turbulent flow

subject: Adverse pressure gradient

subject: Favourable pressure gradient

subject: Compressible channel flow

subject: Pressure gradient vorticity flux correlation

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2009-12-21 13:59:53.084

abstract:
This thesis is focused on direct numerical simulation (DNS) of compressible and
incompressible fully developed and developing turbulent flows between isothermal
walls using a discontinuous Galerkin method (DGM).
Three cases (Ma = 0.2, 0.7 and 1.5) of DNS of turbulent channel flows between
isothermal walls with Re ~ 2800, based on bulk velocity and half channel width,
have been carried out. It is found that a power law seems to scale mean streamwise
velocity with Ma slightly better than the more usual log-law. Inner and outer scaling
of second-order and higher-order statistics have been analyzed. The linkage between
the pressure gradient and vorticity flux on the wall has been theoretically derived
and confirmed and they are highly correlated very close to the wall. The correlation
coefficients are influenced by Ma, and viscosity when Ma is high. The near-wall
spanwise streak spacing increases with Ma. Isosurfaces of the second invariant of the
velocity gradient tensor are more sparsely distributed and elongated as Ma increases.
DNS of turbulent isothermal-wall bounded flow subjected to favourable and adverse
pressure gradient (FPG, APG) at Ma ~ 0.2 and Reref ~ 428000, based on the
inlet bulk velocity and the streamwise length of the bottom wall, is also investigated.
The FPG/APG is obtained by imposing a concave/convex curvature on the top wall
of a plane channel. The flows on the bottom and top walls are tripped turbulent and laminar boundary layers, respectively. It is observed that the first and second order
statistics are strongly influenced by the pressure gradients. The cross-correlation
coefficients of the pressure gradients and vorticity flux remain constant across the
FPG/APG regions of the flat wall. High correlations between the streamwise/wallnormal
pressure gradient and the spanwise vorticity are found near the separation
region close to the curved top wall. The angle of inclined hairpin structure to streamwise
direction of the bottom wall is smaller (flatter) in the FPG region than the APG
region.

abstract: PhD


title: Behaviour of CFRP-Prestressed Concrete Beams under Sustained Loading and High-Cycle Fatigue at Low Temperature

contributor:
Fam, Amir Z.
Green, Mark F.
Civil Engineering

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subject:
CFRP
prestress
prestressed concrete
beam
girder
long-term
sustained load
high-cycle fatigue
cyclic load
low temperature

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2009-12-21 15:16:33.381

abstract:
Fibre-reinforced polymers (FRPs) are becoming increasingly accepted in structural engineering applications.  In particular, Carbon-FRP (CFRP) tendons are proving to be promising as prestressing reinforcement for concrete structures.  While several studies have been conducted on CFRP-prestressed concrete beams, very little attention has been given to their long-term behaviour at low temperatures.  This thesis investigates the behaviour of CFRP prestressed concrete beams in two studies: (a) under sustained loading at low temperature, and (b) under high-cycle fatigue at low temperature.  Seven 13 year old, 4.4 m long precast concrete T beams were tested, of which five were prestressed to various levels with CFRP tendons and two with conventional steel strands.
In the first study, three beams were exposed to −27 °C while being subjected to a sustained load of 25% of their flexural capacity for 163 days.  The sustained load produced cracking in two beams with lower prestress levels.  Results were compared to those obtained from three similar beams subjected to the same sustained load at room temperature.  Deflection increase under sustained load at low temperature was generally small and similar to that at room temperature.  Prestressing strain had a direct relationship with temperature in the CFRP prestressed beams.
After being subjected to sustained loading, all seven beams were tested in the second study.  Only three of the five CFRP prestressed beams were subjected to cyclic loading, one at −28 °C and two at room temperature, while only one of the two steel prestressed beams was subjected to cyclic loading, at −28 °C.  Cyclic loading consisted of 3 million cycles at a frequency of 0.85 Hz.  The load range represented 21 to 42% of the flexural capacity of the CFRP prestressed beams and 30 to 60% of that of the steel-prestressed beam.  Monotonic tests were run every 1 million cycles.  Finally, all seven beams were monotonically loaded to failure.  All CFRP prestressed beams survived the 3 million cycles but the steel prestressed beam failed after 185,000 cycles.  However, the CFRP concrete bond was weakened by high prestress levels, cyclic loading, and low temperature during sustained loading and loading to failure.  This resulted in bond failure at loads ranging from 69 to 91% of the full flexural capacity.  Stiffness and camber gradually decreased during cyclic loading.

abstract: M.A.Sc.


title: A Method to Improve Cartilage Integration

contributor:
Amsden, Brian
Waldman, Stephen D.
Chemical Engineering

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subject:
cartilage
mosaic arthroplasty
chondrocytes
chemotaxis

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2009-12-21 20:16:05.815

abstract: One major barrier that prevents cartilage integration following mosaic arthroplasty is the presence of a zone of chondrocyte death (ZCD) that is generated upon osteochondral graft harvest, which can extend up to 400 μm into the cartilaginous portion of the graft. In order for cartilage integration to occur, chondrocytes must be present at the graft periphery; however chondrocyte migration through the ZCD to the graft periphery is inhibited by the dense extracellular matrix (ECM) of cartilage. The purpose of this study was to develop a method for increasing the number of chondrocytes within the ZCD and at the periphery of a cartilage graft. This method used a combination of collagenase treatment (as a means of degrading the ECM within the ZCD) and chondrocyte chemotaxis (as a means of improving chondrocyte migration into the ZCD and to the cartilage periphery). Results indicate that treating bovine articular cartilage with 0.6 % collagenase for 10 min decreased with extent of the ZCD by approximately 35% (collagenase: 109 ± 13 μm; control: 175 ± 13 μm). Each of the chemotactic agents tested (PDGF-bb, bFGF, and IGF-I) were found to induce bovine chondrocyte chemotaxis at concentrations of 25 ng/mL in modified Boyden chamber experiments. However, in bovine articular cartilage samples that were pre-treated with collagenase (0.6% for 10 min), supplementation with 25 ng/mL of either PDGF-bb or bFGF had no apparent effect on the ZCD relative to samples treated only with collagenase (PDGF-bb: 85 ± 10 μm; bFGF: 88 ± 10 μm). Alternatively, bovine articular cartilage samples pre-treated with collagenase (0.6% for 10 min) and supplementation with 25 ng/mL IGF-I resulted in an approximately 65% reduction in the ZCD relative to samples treated only with collagenase (IGF-1: 38 ± 5 μm). Thus, treating osteochondral grafts with collagenase and IGF-1 induces chondrocyte repopulation of the zone of chondrocyte death generated by osteochondral graft harvesting, and could enhance cartilage integration after implantation.

abstract: M.A.Sc.


title: In Parables: The Narrative Selves of Adolescent Girls

contributor:
Luce-Kapler, Rebecca
Education

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subject:
adolescent girls
narrative
at-risk
self
resilience
storytelling
artmaking
parables

abstract: Thesis (Ph.D, Education) -- Queen's University, 2009-12-18 17:19:42.63

abstract:
I began with an interest in what makes a difference for girls who face challenging circumstances: What helps them to develop sturdy, resilient, and resistant selves? What role does narrative play in this process?
I set in motion a process of storytelling and reflecting by inviting girls and women to share stories together—their own stories, fictional narratives, and myths. The participants had faced particular challenges in adolescence, including economic hardship; disrupted social or family circumstances; mental health; abuse; or trauma. The girls and women had differing racialized, class, cultural, social, religious, and ethnic backgrounds.
Drawing on the work of biblical scholars who understand Jesus’ parables as poetic metaphor, I identified 11 aspects of parables that helped me to hear and interpret girls’ stories: participation, difficulty, metaphor, fractals, truth, emergence, performance, possibility, power, wisdom, and beauty. Listening with a parabolic ear, I came to experience girls’ storytelling selves as participatory, metaphorical, fractal, truthful, and emergent; I observed girls’ selves as artistic practices that are embodied performances of their wisdom, power, and beauty. And I discovered how such performances of the self create enlarged spaces of possibility for girls in the face of life’s difficulty.
I discovered that storytelling selves are girls’ power—power realized as storytelling, participation, mutual relation, meaning-making, enlarging spaces of possibility, disidentification, and embodiment.
I identified six elements that seemed to be important in nurturing girls’ parabolic imagination. These are community participation, experienced observation, complexity, care, interpretation, and artmaking. These elements provide a framework for considering how educators might support girls’ selves but they do not provide a methodology. Taken together, they are more like a parable—an opening onto a particular worldview that invites participation in the world of a girl.
These six elements may be signs that point to places where parables of the self are already being told. They become questions that make sense only to those who already understand: Is this community? Is anyone listening? Is it complex? Is this a place of compassion and care? Is meaning being shaped and questioned and reimagined here? Is there art? Is there play?

abstract: PhD


title: Minimizing Carbon Emissions in Metal Forming

contributor:
Kim, Il-Yong
Jeswiet, Jack
Mechanical and Materials Engineering

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subject:
Carbon Emissions
Optimization
Manufacturing

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-12-19 16:39:12.071

abstract:
The present work deals with the calculation and the investigation of possible reductions of CO2 emissions in manufacturing a metal formed product.
The industrial sector plays a significant role in the recent increase of the oncentration of Greenhouse Gases in the atmosphere, which is responsible for the advancing global warming. As an answer to fiscal and financial intervention of government policies aimed at counteracting this phenomenon, the environmental impact of products became a key aspect of a company’s strategy.
However, literature still lacks effective methods and quantitative studies that look into the details of a single manufacturing process, discussing its environmental aspects and how they can be influenced by changes in the technological parameters.
In an attempt to do that, an example of quantification and minimization of the carbon emissions occurring during the two manufacturing steps of the fabrication of an Al 6061 disc is provided. Electrical energy consumption occurring during the shearing and the upset forging of a billet was found by means of nonlinear finite element analysis and converted into CO2 emissions with a carbon emission signature value (CES). Environmental impact and frictional properties of both traditional lubrication and two non-conventional ecologically benign lubricants (palm oil ester and used cooking oil ester) were experimentally tested and are included in the study.
A gradient-based optimization algorithm was implemented to determine the optimal geometry of the billet before the compression as well as the lubricant that minimize the total carbon emissions, within the proper technological limitations and constraints on the final product quality.
A clear and effective method which would represent an auxiliary decision tool for a manufacturer in the metal forming sector is hereby presented. Results show that the selection of the manufacturing options can have an influence of more than 13% on the overall CO2 emission.

abstract: M.A.Sc.