title: MOSFET Current Source Gate Drivers, Switching Loss Modeling and Frequency Dithering Control for MHz Switching Frequency DC-DC Converters

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subject:
Electrical Engineering
Power Electronics
MOSFET Gate Drive
Switching Loss
Frequency Dithering
Switching Loss Modeling

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2008-02-28 10:56:06.732

abstract:
The power density of a switching converter is dependent on the size of the power circuit components.  Converters are operated in the hundreds of kHz to achieve high power density since the size of the converter reactive components decrease as frequency increases.  Most present day low power (<200W) DC-DC converters operate at switching frequencies up to 500kHz.  Some research has been conducted on converters that can operate above 500kHz up to 4MHz.  In the near future, most DC-DC switching converters for communications and computers will operate at switching frequencies of 1-10MHz in order to achieve greater power density and improved transient response.  To meet the next generation requirements of these applications, four new ideas are proposed in this thesis.

The first contribution is a new current source gate drive circuit for power MOSFETs.  The circuit provides a nearly constant gate current to reduce switching transition times and therefore switching loss in power MOSFETs.  In addition, it can recover a portion of the gate energy normally dissipated in a conventional driver.  Demonstrated loss reduction of 24.8% at 10V/5A load are presented in comparison to a conventional voltage source driver for a boost converter switching at 1MHz.

The second contribution is a new high efficiency 1MHz synchronous buck voltage regulator using an improved current source driver.  The proposed circuit achieves short rise and fall times to reduce switching loss in the buck HS MOSFET.  It also recovers a portion of the SR gate energy, enabling a loss reduction of 24% at 1.3V/30A load in comparison to a conventional driver.

In the third contribution, a new switching loss model is proposed for synchronous buck voltage regulators.  The model uses simple closed form equations to calculate the rise and fall times and piecewise linear approximations of the HS MOSFET voltage and current waveforms to allow quick and accurate calculation of switching loss.

The final contribution is a new variable frequency digital control method for resonant converters, which is suitable for future applications switching at 10MHz.  The proposed method uses frequency dithering to reduce the clock frequency demands of the digital controller.

abstract: PhD


title: The Neighbourhood Imaginary : Considerations of Local Art Production in Unconventional Spaces

contributor:
Jessup, Lynda
Lord, Susan
Art History

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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:
Contemporary Art
Public  Unconventional Sites

abstract: Thesis (Master, Art History) -- Queen's University, 2008-02-29 13:04:52.207

abstract:
This thesis examines contemporary art projects that are installed in unconventional sites
in urban neighbourhoods. Using the conceptual framework of the neighbourhood
imaginary, I propose that these local art practices utilize neighbourhood spaces to engage
with nation, identity and citizenship practices within the contemporary discourse of
globalization. The three art projects I investigate address different aspects of
neighbourhood. Cuban artist René Francisco Rodriguez’s (René Francisco) project, El
Patio de Nin, foregrounds the citizen in an urban neighbourhood. His project merges
creativity and pedagogy with social service, and blurs the boundaries between art and life
in order to comment on social conditions and citizenship practices. The Legacy of Joseph
Wagenbach (2006), by Toronto artist Iris Häussler, uses a home in an urban
neighbourhood as a physical space in which to create an imaginary life to explore aspects
of community, human behaviour and social values. The Swamp Ward Window, a
Kingston-based curatorial project, takes advantage of the intimacy of the private home
and the immediacy of the street to present artworks that explore the interface between
public and private and everyday life in the community.
Cornelius Castoriadis argues that the social imaginary emerges when the subconscious,
the symbolic and action interact, not merely to reflect the outside world, but to create new
meanings from which social change is possible. In my analysis, the neighbourhood
imaginary resonates with the social imaginary, functioning as a conceptual laboratory for
artists to experiment with the different meanings associated with neighbourhood,
community and citizenship. I propose that a reengagement with the local, as part of a
iii
global discourse, provides an opportunity to examine art projects that manifest in
neighbourhoods. And, while taking place in different socio-political circumstances, the
shared condition of locality, I argue, provides a window through which the three projects
envision linkages between aesthetic practices and public life. Finally, in order to
critically consider local artistic practices in relation to globalization and the
commodification of culture, this thesis engages those discourses of globalization that see
culture as integral in new global economies.

abstract: M.A.


title: Combined effects of freeze-thaw and sustained loads on reinforced concrete beams strengthened with FRPs

contributor:
Green, Mark F.
Civil Engineering

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subject:
FRP
Freeze-thaw
Sustained load
Concrete

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2008-02-29 14:19:29.954

abstract:
Fibre reinforced polymer (FRP) materials have emerged as an innovative tool within the civil engineering community for the strengthening and rehabilitation of existing reinforced concrete structures. Research has taken place over the past decade that has demonstrated the benefits of FRPs, and it is evident that there is a need for their usage given the status of the deteriorated North American civil infrastructure. However, in order to increase confidence in the application of these materials in Canada, further information is required to fully understand their behaviour in cold climates.

This thesis expands on the previous research that has taken place at Queen’s University, investigating the freeze-thaw behaviour of FRP strengthened reinforced concrete. The research program herein studies the combined effects of freeze-thaw cycling and sustained loading on the flexural performance of 45 small-scale beams strengthened with glass FRP sheets, carbon FRP sheets, or carbon FRP plates. In an attempt to attain failure of the beams due to FRP rupture, the anchorage of the beams was increased and a theoretical model was produced to select the beam design for this failure mode. The model also predicted the performance of the strengthened beams in order to determine appropriate sustained loading levels. After being subjected to 300 freeze-thaw cycles and almost 3 months of sustained loads, the beams were tested to failure. It was found that the beams subjected to combined loads encountered virtually no losses in average ultimate strength. However, the greater inconsistency of the results for these beams relative to the control beams implies that lower guaranteed strengths should be used for design in situations where these conditions are present.

abstract: M.Sc.


title: Time and time again: cultural differences in construal levels

contributor:
Ji, Li-Jun
Psychology

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subject: Culture Time

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2008-02-29 15:11:16.087

abstract: People mentally represent information, objects, and events in a variety of ways.  The purpose of the present program of research was to investigate how culture affects the way people represent temporal information.  I hypothesized that increased temporal distance would lead Canadians to think more abstractly, and that this shift toward abstraction would be smaller, or non-existent, among Chinese.  To test this hypothesis, I ran three studies with 490 participants in Canada and China (237 Canadian participants and 253 Chinese participants).  In Study 1, Canadians preferred to describe actions more abstractly in the distant future than near future, and Chinese did not show this shift.  In Study 2, Canadians generated fewer categories in the distant future than in the near future, whereas Chinese did not differ across time.  In Study 3, Canadians recalled information about a target event either within two days after the event occurred or approximately two weeks later.  Consistent with my hypotheses, Canadians’ coded responses shifted toward abstraction with increased temporal distance, and Chinese did not show such a shift. A meta-analysis based on all three studies revealed that Canadians mentally represent distal events and objects more abstractly and in a less detailed way than proximal events and objects, and that Chinese showed no time effect.

abstract: PhD


title: Hip and knee frontal plane biomechanics in people with medial compartment knee osteoarthritis

contributor:
Culham, Elsie
Rehabilitation Science

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subject:
Osteoarthritis
Biomechanics
Knee
Hip abductor muscles

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2008-03-03 21:47:07.309

abstract: Objectives: To investigate differences between hip abductor muscle strength, hip and knee adduction moments and knee joint alignment in people with moderate/severe and mild medial compartment knee osteoarthritis (OA), and people without OA, and identify variables explaining variance in knee adduction moment in participants with OA. Background: It has been suggested that weakness of hip abductor muscles may lead to displacement of the centre of mass of body away from the stance limb during gait, resulting in increased knee adduction moment, a predictor of disease progression. Methods: Participants with medial compartment knee OA were divided into moderate/severe (n=23) and mild OA groups (n=15) based on radiographic grading. Control subjects were recruited to match participants in the moderate/severe group for age and gender (n=23). Hip abductor and adductor muscle isometric strength was measured using the Biodex dynamometer. Gait speed and hip and knee peak adduction moments and percentage of the stance phase where these occurred were obtained using a three dimensional motion analysis system and two force platforms. Knee alignment and severity of OA were measured from radiographs. Statistics: Univariate analysis of variance (ANOVA) was performed to determine group differences. Stepwise linear regression analysis was performed to identify the variables which contribute to variation in knee adduction moment. Results: Moderate/severe OA group participants had higher body mass index (BMI) than the mild OA and control group (p=0.01) and greater varus alignment compared to the control group (p<0.01). There was no difference between the mean hip abductor and adductor muscle strength and hip and knee adduction moments among the three groups. Peak hip (p=0.02) and knee adduction moments (p<0.05) occurred later in stance phase of gait in the moderate/severe OA group as compared to control group. Knee joint alignment (26%), hip abductor muscle isometric strength (20%), gait speed (16%) and hip adduction moment (11%) explained 73% of variance in the knee adduction moment in the participants with OA. Conclusion: Findings from this study do not support the theory that weakness of the hip abductor muscles contributes to higher knee adduction moments.

abstract: M.Sc.


title: Late and early transition metal-catalyzed homo and copolymerizations studies of olefins and polar monomers

contributor:
Baird, Michael C.
Chemistry

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subject: Polymerization Organometallic

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2008-03-03 12:08:49.539

abstract:
The aims of this work were two-fold.

The first part of this thesis involves the synthesis of the Brookhart’s diimine catalyst [Pd(N-N)Me(Et2O)]+ (1) (N-N = (2,6-(i-Pr)2C6H3)-N=CH2CH2=N-(2,6-(i-Pr)2C6H3)) and an investigation of its insertion behaviour with the polar monomer acrylonitrile (AN), as well as its copolymerization behaviour with ethylene. Acrylonitrile displaces the ethyl ether ligand of Brookhart’s cationic complex [Pd(N-N)Me(Et2O)]+ (1) to form the N-bonded species [Pd(N-N)Me(AN)]+ (2) which exists as two equilibrating rotamers (2a and 2b). On heating, [Pd(N-N)Me(AN)]+ which appears to undergo 2,1-insertion, presumably via an unobserved 2 isomer, to give the new complex, [Pd(N-N)(CH(CN)CH2CH3)(AN)]+ (3) which apparently undergoes subsequent -hydrogen elimination to give a hydride which then reacts further with AN to give a cyanoethyl complex (5). Although [Pd(N-N)Me(AN)]+ does behave as a typical Brookhart ethylene polymerization catalyst, it does not catalyze AN polymerization and added AN suppresses ethylene polymerization. [Pd(N-N)Me(AN)]+ does not copolymerize ethylene and acrylonitrile.
	The second part of this thesis involves utilizing the early metal catalyst rac-Et(Ind)2ZrCl2 (Ind = C9H7) /methylaluminoxane (MAO) to copolymerize propylene or ethylene and the compounds CH2=CH(CH2)7CH2OR {R = Me, (A); PhCH2, (B); Ph3C, (C); Me3Si, (D); Ph3Si, (E)}, all ethers of 9-decen-1-ol. The results showed new copolymer materials of up to 2.0 mol % of incorporated polar monomer into polypropylene and 1.2 mol % for polyethylene. All materials were characterized by 1H and 13C NMR spectroscopy, differential scanning calorimetry and infrared spectroscopy. It was found that the increasing bulkiness of protecting groups did not increase the amount of polar monomer within the copolymers obtained. As a control, propylene-1-hexene copolymerization results were found to be comparable to those results of the polar monomer copolymerization results (up to 2.9 mol % of 1-hexene incorporated).
	Furthermore, 1H NMR monitoring reactions of the homopolymerization of these vinyl and silyl ethers (A - E) were investigated with the zwitterionic compound G [Cp2ZrMe][MeB(C6F5)3] (Cp = C5H5). It was found that the protecting groups were effective in protecting the functional group from poisoning the catalyst.
Finally, the "aging" of MAO by heating, removing trimethylaluminum (TMA) or adding water content all proved to contribute adversely in copolymerization results, whereas adding oxygen content proved to have little effect.

abstract: PhD


title: Deposition and diagenesis of the early Permian Lower Parmeener Supergroup limestones, Tasmania

contributor: Geological Sciences and Geological Engineering

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subject:
Cold-water carbonate
Permian
Tasmania
Diagenesis

abstract: Thesis (Ph.D, Geological Sciences & Geological Engineering) -- Queen's University, 2008-04-23 11:12:58.461

abstract:
The Lower Parmeener Supergroup consists of 500 to 900 metres of marine and terrigenous sedimentary rocks, deposited in the high-latitude Tasmania Basin during the late Carboniferous to middle Permian, at the end of the late Paleozoic ice age.  Two bioclastic carbonate units, the Darlington and Berriedale limestones, are of particular interest due to their formation in this polar, cold-water environment.  Both limestones contain ice-rafted debris scattered throughout, signifying numerous icebergs, and are under- and over-lain by glendonitic siltstone indicating near-freezing seawater.  Despite the unusual environment, seawater in the Permian Tasmania Basin was, with the exception of an anomalously high 13C value, isotopically and chemically similar to modern seawater.

These limestones consist of a high-abundance, low-diversity heterozoan assemblage, dominated by large, robust brachiopods, bryozoans, and Eurydesma bivalves.  Sponge spicules and crinoids are locally important constituents.  The carbonates are interpreted to have been deposited in mid-shelf environments during sea-level highstands, where the faunal communities were beyond the depths of grounding icebergs, and sufficiently outboard from terrigenous sediment influx and brackish water.  Growth and preservation of biogenic carbonates were promoted by up-welling of nutrient-rich water, which sustained high levels of primary productivity in the water column and phosphate concentrations in the sediment.

Lower Parmeener Supergroup carbonates were exposed to a complex series of diagenetic processes, commencing on the seafloor and continuing during rapid burial.  Limestone composition was further modified by diagenetic fluids associated with the intrusion of Mesozoic igneous rocks.  Alteration in the marine paleoenvironment was both destructive and constructive; although dissolution took place there was also coeval precipitation of fibrous calcite cement, phosphate, and glauconite.  These processes are interpreted to have been promoted by mixing of marine waters and enabled by microbial degradation of organic matter.  In contrast, meteoric diagenesis was insignificant, being confined to minor dissolution and localized cementation, although mechanical compaction was ubiquitous.  Chemical compaction was instigated at burial to depths of approximately 150 m, and promoted extensive precipitation of ferroan calcite.  Diagenesis may well have ended here, except for the subsequent intrusion of massive Mesozoic diabases and associated injection of silicifying fluids into the limestones.  Finally, fractures associated with Cretaceous uplift were filled with late-stage non-ferroan calcite cement.

abstract: NSERC

abstract: PhD


title: Investigation of the effect of intrauterine inflammation and infection on fetal brain injury using human and animal models

contributor:
Smith, Graeme N.
Anatomy and Cell Biology

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subject:
Inflammation
Pregnancy
Fetal Brain Injury
Proinflammatory Cytokines

abstract: Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2008-03-06 20:24:03.417

abstract:
In recent years, increased focus has been placed on the role of intrauterine infection and inflammation in the pathogenesis of fetal brain injury leading to neurodevelopmental disorders such as cerebral palsy. At present, the mechanisms by which inflammatory processes during pregnancy cause this effect on the fetus are poorly understood.  Our previous work has indicated an association between experimentally-induced intrauterine infection, increased proinflammatory cytokines, and increased white matter injury in the guinea pig fetus.  In order to further elucidate the pathways by which inflammation in the maternal system or the fetal membranes leads to fetal impairment, a number of studies investigating aspects of the disease process have been performed.  These studies represent a body of work encompassing novel research and results in a number of human and animal studies.

Using a guinea pig model of inflammation, increased amniotic fluid proinflammatory cytokines and fetal brain injury were found after a maternal inflammatory response was initiated using endotoxin.  In order to more closely monitor the fetal response to chorioamnionitis, a model using the chronically catheterized fetal ovine was carried out.  This study demonstrated the adverse effects on fetal white matter after intrauterine exposure to bacterial inoculation, though the physiological parameters of the fetus were relatively stable throughout the experimental protocol, even when challenged with intermittent hypoxic episodes.

The placenta is an important mediator between mother and fetus during gestation, though its role in the inflammatory process is largely undefined.  Studies on the placental role in the inflammatory process were undertaken, and the limited ability of proinflammatory cytokines and endotoxin to cross the placenta are detailed herein.

Neurodevelopmental disorders can be monitored in animal models in order to determine effective disease models for characterization of injury and use in therapeutic strategies.  Our characterizations of postnatal behaviour in the guinea pig model using motility monitoring and spatial memory testing have shown small but significant differences in pups exposed to inflammatory processes in utero.

The data presented herein contributes a breadth of knowledge to the ongoing elucidation of the pathways by which fetal brain injury occurs.  Determining the pathway of damage will lead to discovery of diagnostic criteria, while determining the vulnerabilities of the developing fetus is essential in formulating therapeutic options.

abstract: PhD


title: A Lanczos study of superconducting correlations on a honeycomb lattice

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subject:
Physics
Condensed matter
Superconductivity
Exact diagonalization

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2008-03-17 14:06:20.094

abstract: In this thesis superconducting correlations on both a one-dimensional chain and a two-dimensional honeycomb lattice are analyzed using the t-J model Hamiltonian. Both systems use periodic boundary conditions and different electron fillings, and both are solved numerically using the Lanczos algorithm. In order to search for superconducting correlations in the ground state the pair-pair correlation and susceptibility functions are defined. In one dimension the correlation function, at lower electronic fillings, displayed appreciable, non-zero values for all pair-pair separations. In general, the one-dimensional results were consistent with the literature. However, the honeycomb results did not show such strong superconducting correlations, as the correlation function remained close to zero for most separation distances.

abstract: M.Sc.


title: Affective processing in acute alcohol intoxication

contributor:
Olmstead, Mary C.
Psychology

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subject:
Affective processing
Alcohol

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2008-03-20 14:29:40.722

abstract: Maladaptive decision-making that typifies drug addiction could reflect alterations in cognitive and emotional processing when these individuals are faced with choices. Even if this is true, it is not clear whether these deficits are a cause or a consequence of chronic drug use. The following experiments were designed to determine the effect of acute alcohol intoxication on affective processing in healthy individuals, as measured through a variety of behaviours. In the first experiment, acute alcohol intoxication did not impair performance on a task that recruits the orbitofrontal cortex, a key area for decision-making. In the second experiment examining preference formation, there was a clear dissociation between alcohol’s effect on implicit and explicit memory: acute intoxication impaired explicit memory, while leaving implicit learning intact. In a subsequent experiment, both alcohol and placebo groups showed altered physiological and subjective responses to a psychosocial stressor. Although acute alcohol intoxication did not affect risk-taking, an individual variable (tension-reactivity) moderated performance on this laboratory task. This experiment also revealed a relationship between stress-reactivity and subsequent risk-taking, one explanation being that high levels of cortisol increased individual sensitivity to task outcomes. Finally, an analysis of the accumulated information on drinking rates, impulsivity, and drug use suggests that female drinking rates may be approaching the levels reported by males. There were also significant differences in sensitivity to alcohol’s effects when participants were intoxicated in the lab. Heavy drinkers showed a greater sensitivity to the pleasurable effects of alcohol despite feeling less intoxicated and desiring more alcohol than other individuals. These combined effects could put heavy drinkers at greater risk for alcohol-related problems. Taken as a whole, these studies suggest that individual factors play a stronger role in moderating affective processing than do the direct pharmacological effects of alcohol.

abstract: PhD


title: Consuming the "Oriental Other," Constructing the Cosmopolitan Canadian: Reinterpreting Japanese Culinary Culture in Toronto's Japanese Restaurants

contributor:
Kobayashi, Audrey
Geography

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subject:
food geographies
cosmopolitanism
Other
racism
Japanese
Toronto

abstract: Thesis (Ph.D, Geography) -- Queen's University, 2008-03-24 15:40:29.811

abstract: During the last decade, Japanese cuisine has become firmly rooted in Canada. The once unusual sounding dishes such as sushi, tempura, and edamame are now familiar to most Canadians. Indeed, Japanese restaurants make up a substantial portion of Toronto’s diverse foodscape, yet little is known about how this culinary culture is understood, how the constructed image is created, and the identities that are produced through its production and consumption. This dissertation aims to unpack the constructed identities of the cosmopolitan and the “Oriental Other” contained within Japanese culinary circuits in Toronto, while also examining the connections, constructions, and negotiations concealed within the Japanese restaurants’ cultural landscape. It seeks to highlight the processes of racialization, Whiteness, and the articulation of difference that are interconnected and interdependent on the production and consumption of Japanese food in Toronto’s restaurants. Through this process, cultural differences are mapped out, allowing Japanese cuisine to become an accessible and readily available place to search for cosmopolitan identity making and the performance of Otherness. To this aim, in-depth interviews were conducted with residents of Toronto and chefs of Japanese ethnic origin. Both groups emphasize the relations between food providers and consumers, authenticity strategies, and their imaginative geographies of Japanese culinary culture but had remarkably different interpretations on how these constructions are practiced, articulated, and ultimately understood.

abstract: PhD


title: The Identification of BRCA1 and BRCA2 Mutation Carriers Using Functional Genomic Assays

contributor:
Davey, Scott
Feilotter, Harriet
Pathology and Molecular Medicine

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subject:
BRCA1
BRCA2
Hereditary Breast Cancer
Microarrays
Cancer Screening
Mutation Carriers

abstract: Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2008-03-27 15:38:19.269

abstract:
An estimated 5-10% of breast cancers are hereditary in nature and are due to the presence of a mutation in a breast cancer predisposition gene; approximately half of these cases possess a mutation in BRCA1 or BRCA2. Many BRCA1/BRCA2 mutations result in a truncated protein and hence are unequivocally disease-causing. However another class of mutations, the Variants of Unknown Significance (VUS), are more problematic as the effect of these mutations on protein function is unclear. The inability to classify these mutations as disease causing generates significant problems in risk evaluation, counseling and preventive care. Accordingly we sought to determine whether carriers of either a BRCA1 or BRCA2 mutation could be identified from non-carriers based on the gene expression patterns of non-cancerous cells.
EBV-transformed lymphoblastoid cell lines established from BRCA1/BRCA2 mutation carriers and normal individuals were obtained through the NIH Breast Cancer Family Registries. Cell lines were mock-irradiated or treated with ionizing radiation (2 Gy). Following a recovery period of 6 hours total RNA was extracted and whole genome gene expression profiling was carried out. Molecular classifiers comparing the baseline expression profiles and the radiation-dependent expression profiles of BRCA1/BRCA2 mutation carriers to control individuals were created using a Support Vector Machine (SVM) coupled with a recursive feature removal (RFR) algorithm.
Our results suggest that cell populations derived from BRCA1/BRCA2 mutation carriers display unique expression phenotypes from those of control individuals in both the basal and radiation-induced cases. In the task of classification using baseline expression, the BRCA1-classifier correctly classified 15/18 test samples using feature selection based on the training set only, while feature selection using the entire dataset (AD) improved classification to 16/18 samples. The BRCA2-baseline classifier correctly classified 13/17 and 14/17 (AD) samples, respectively. In the task of radiation-dependent classification, the BRCA1-IR classifier correctly classified 12/18 and 16/18 (AD) test samples respectively while the BRCA2-IR classifier correctly classified 13/17 and 16/17 (AD) test samples respectively. These results suggest the possibility of development of this assay into a novel hereditary breast cancer screening diagnostic able to accurately identify the presence of BRCA1 or BRCA2 mutations via a functional assay thereby improving patient outcomes.

abstract:
Canadian Breast Cancer Foundation-Ontario Chapter,
Department of Pathology & Molecular Medicine Clinical Trust Fund

abstract: The assay created and detailed in this thesis is in the process of being patented and thus needs to remain restricted for the time being.

abstract: M.Sc.


title: Canadians Against Fire: Canada's Soldiers and Marshall's "Ratio of Fire" 1944-1945

contributor:
English, Allan
History

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subject:
History
Military
Canada
S.L.A. Marshall

abstract: Thesis (Master, History) -- Queen's University, 2008-03-31 14:57:42.693

abstract:
This thesis investigates one of the staples of academic literature on combat motivation, S.LA. Marshall's “ratio of fire,” through the examination of previously untouched primary-source documentation from the Second World War. This evidence, a series of Battle Experience Questionnaires filled out by combat infantry officers of the Canadian Army in 1944 and 1945, details a wide range of tactical issues experienced by soldiers in battle. The interpretation and implications of this data for the “ratio of fire” theory is discussed, as the questionnaires make detailed inquiry into weapon use, infantry
co-operation with other arms, and general combat effectiveness. The thesis concludes
that this documentary evidence strongly supports the idea that, at the least, Marshall's “ratio of fire” statements are inapplicable to the Canadian experience of the Second World War, and that the body of literature based upon Marshall's conclusions deserves a critical re-examination.

abstract: M.A.


title: l'Humour et l'ironie en litterature francophone subsaharienne. Une poétique du rire

contributor:
Nshimiyimana, Eugene
French

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subject:
humour
littérature africaine
irony

abstract: Thesis (Ph.D, French) -- Queen's University, 2008-04-01 11:23:19.947

abstract:
Humour and Irony are identity markers that have long since been associated with Sub-Saharan francophone literary works. Intimately linked to Africa throughout the years, humour and irony have evolved hand to hand with socio-political situation of the continent and fulfill several functions: denouncing through laughter, varying sorts of injustices, playing down the tragic nature of a given situation and subverting individual or collective values. However, and perhaps more importantly, humour and irony belong the category of what Roland Barthes calls "verbal expedients" which allow a writer to avoid common and inadequat usage of language. In this way, we show by using the theorical frameworks of Bergson, Schopenhauer, Jankelevitch, Escarpit and Genette among many others just how humour and irony create a particular vision, one that shows the multiple ways in which we can perceive the world around us. They make possible the representation of what is undeniably real and bring out polysemous meannings(s) in that which may at first appear incongruous.
Given the numerous interpretations that humour and irony offer for a given situation, theses devices thus constitute strategies that build different esthetics within the novel as a literary genre. The latter becomes a sort of semantic playgroung where the specific forms of humour and irony develop: parody, derision, sarcasm,the grotesque and the farce. It is in this way that a veritable "poetics oflaughter" becomes apparent within the novels that we have examined.

abstract: PhD


title: Flameless Combustion of Natural Gas in the SJ/WJ Furnace

contributor:
Matovic, Miodrag
Mechanical and Materials Engineering

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subject:
Flameless Combustion
Strong-Jet/Weak-Jet
Numerical Simulation

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2008-04-04 11:25:25.455

abstract:
Flameless combustion in a 48 kW pilot scale furnace fired with natural gas is studied
experimentally and computationally. The burner geometry involved a tunnel furnace with two separate feed streams --- one for a high momentum air jet and the other for a low momentum fuel jet. This burner configuration, called a Strong-Jet/Weak-Jet (SJWJ) burner, together with the jetto-
jet interactions generate the flameless combustion mode with relatively uniform furnace gas temperature distributions and low NOX emissions. Experiments were carried out under laboratory conditions for turbulent reactive mixing in order to obtain local temperature and gas concentrations. The experimental findings were used to test the performance of CFD numerical models for turbulence, mixing and chemical reactions.

For the SJWJ furnace operated in flameless combustion mode, 32 different flow cases were
examined to assess the effects of the three main parameters (fuel/air momentum flux ratio, fuel/air nozzle separation distance and fuel injection angle) on the furnace wall temperature profile. Three specific flow configurations were selected for detailed near-field temperature
measurements. The gas temperature distribution inside the combustion chamber was found to be relatively uniform, a characteristic of flameless combustion. Four flow configurations were studied to examine the effect of the fuel jet injection angle (0 degrees or 10 degrees) and fuel/air
momentum flux ratio (0.0300 and 0.0426) on the mixing, combustion performance and NOX
emissions. Gas compositions were measured in the flue gas and within the furnace at selected locations to estimate the concentrations of CO2 CO, CH4, O2, NO and NOX. The NOX concentrations in the flue gas were quite low, ranging from 7 - 13 ppm, another characteristic of flameless combustion.

The combusting flow CFD calculations were carried out using the k-ε turbulence model and the eddy-dissipation model for methane-air-2-step reactions to predict the temperature and concentration field. The numerical results for gas temperature and compositions of CH4, O2 and CO2 generally showed good agreement with the experimental data. The predicted CO concentration profiles followed expected trends but the experimental data were generally underpredicted. The NOX concentrations were estimated through post-processing and these results were significantly underpredicted.

abstract: PhD


title: The development of understanding of the concept of variable in grade seven beginning algebra students:  the role of student interaction

contributor:
Roulet, Geoffrey
Education

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subject:
Student interactions
Individual and group learning
Patterns of negotiations

abstract: Thesis (Master, Education) -- Queen's University, 2008-04-07 19:10:42.808

abstract:
This thesis reports on a qualitative study of student interactions in one grade seven mathematics classroom as the students worked through a series of tasks exploring multiple uses of variables.  Student tasks were planned out by me, as the teacher and the researcher, and they were executed in my classroom, where I had worked to create a constructivist classroom environment.  This study posed two research questions: (1) In what ways do student interactions during group activities promote the development of individual and collective understanding of the concept of variable? and (2) In what ways do student interactions during whole-class discussions promote the development of individual and collective understanding of the concept of variable?
	I used research methods in which I was a participant.  Data was collected in the form of audio taped discussions for the participants (working in three groups of four). Audio files of class discussions were accumulated and stored for later review.  Written student work and reflections were collected for all class members at the time of the study. From these data sources, the relevant data set emerged.
Analysis came in the form of thick description of eight episodes of importance in which the multiple data sources came together to highlight how student interactions in the form of negotiations may have promoted a shift in understanding of variable. The data showed the complex nature of student interactions along with the potential benefits to student learning.  The data showing these benefits were outlined as three patterns of negotiations.  These were:  negotiations with other students, negotiations with self, and negotiations with the teacher.

abstract: M.Ed.


title: The experiences of Canadian women in popular music:  “even on the worst sick no gas freezing Canadian middle of January rockie mountain or Halifax breakdown there is nothing better to do for a living”

contributor:
Lamb, Roberta
Education

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subject:
Music
Gender roles
Popular music
Canadian popular music
Canadian women
Identity
Gender stereotyping
Sexual harassment
Music teachers
Professional musicians

abstract: Thesis (Master, Education) -- Queen's University, 2008-04-10 10:30:48.856

abstract: This study examined the personal and professional experiences of Canadian professional female popular musicians. The researcher gathered data in two phases. In phase one, 85 female musicians completed a 105-question on-line survey. In phase two, the researcher interviewed four musicians to expand and elucidate survey data. In keeping with a critical feminist approach, the researcher’s voice is prominent in the report. The study reveals a complex combination of personal and professional circumstances that both compel and impel women to become musicians, and then to cleave to or to abandon careers in the music industry. Families, peers, role models, and teachers all have some effect on personal and professional choices that musicians make. Gender stereotyping and sexual harassment prevail in both music education and the music industry, making these contested sites for women musicians. However, respondents’ identity as “musician” is a powerful force, in both personal and professional realms, making both education and industry also sites of triumph. Important findings include: respondents’ reflections on what makes for a successful pop musician; data revealed no essential biographical precursors for success in pop music; respondents’ opinions about the importance of music lessons are divided; and, along with credible technical music skills, musicians need to develop strong personal, social, and business skills.

abstract: M.Ed.


title: Analytical and Numerical Modelling of Thermal Conductive Heating in Fractured Rock

contributor:
Kueper, Bernard H.
Civil Engineering

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subject:
hydrogeology
environmental engineering

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2008-04-25 15:22:38.719

abstract:
Analytical and numerical modelling studies were conducted to assess the performance of thermal conductive heating (TCH) systems for the purpose of contaminated site remediation.  Modelling was conducted in a fractured bedrock environment containing a system of parallel, equally-spaced horizontal fractures.

A semi-analytical solution to the two-dimensional heat conduction equation was developed and used to study temperature distributions between two thermal wells.  A sensitivity analysis was conducted to assess the relative importance of hydrogeological parameters (hydraulic gradient, fracture aperture, fracture spacing) and rock material properties (density, thermal conductivity, heat capacity).  Hydrogeological parameters were far more important than rock material properties in determining treatment zone temperature distributions.  Knowledge of the bulk groundwater influx may be sufficient to predict the temperature within the treatment zone for low to moderate values of influx.

To further the analysis, numerical modelling was employed.  A three-dimensional domain was constructed, representing a symmetrical portion of a heater well cluster.  Simulations were run for different combinations of bulk permeability, fracture spacing, matrix permeability, and matrix porosity.  Flow concentration in fractures had a significant effect on treatment zone temperature distributions when bulk permeability was high.  For low values of bulk permeability, the minimum treatment zone temperature changed by less then 7% when modelling the fractured medium as an equivalent homogeneous porous medium.

Fracture spacing significantly influenced the time needed reach complete steam saturation, even in cases where it did not affect temperature distributions.  A pressure rise may occur in the matrix as water expands thermally, elevating the boiling point of water.  The magnitude of the pressure rise is affected by the distance to the nearest fracture, as well as the matrix permeability and porosity.  For a given bulk permeability, the time needed to reach complete steam saturation will be lengthened by an increase in fracture spacing, an increase in matrix porosity, or a decrease in matrix permeability.  Of these parameters, the matrix permeability is the most significant.

The time needed to reach complete steam saturation in the matrix cannot be predicted if the fracture spacing, matrix permeability, and porosity are not known.  Further, a clear temperature plateau is not observed during boiling in the matrix, posing a difficulty in monitoring thermal treatment, where temperature measurements may be the only information available.

abstract:
1.  U.S. Department of Defense Environmental Security Technology Certification Program (Project ER-0715)
2.  NSERC (Discovery Grant)

abstract: M.Sc.


title: Between man and machine: a socio-historical analysis of masculinity in North American motorcycling culture

contributor:
Hamilton, Roberta
Adams, Mary Louise
Sociology

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subject:
Motorcycling
Pierre Bourdieu
Feminism
Judith Butler
Sport
Sociology
Biker

abstract: Thesis (Master, Sociology) -- Queen's University, 2008-05-07 06:21:18.665

abstract:
There has been a longstanding fascination with motorcycling culture in popular mainstream North American media, but this culture has only recently become the focus of rigorous, contextualized academic research. While smaller research projects have studied specific aspects of motorcycling culture, few academic researchers have investigated the exclusionary discourses that underpin motorcycling culture and none have done so in a methodical manner. Using a series of columns published over a thirty-five year period in the popular Canadian motorcycle magazine, Cycle Canada, I have analyzed the discourses through which motorcycling culture comes to have meaning to its participants and I have elucidated the socio-historical understandings of masculinity that are present in North American motorcycling culture.
This thesis provides a historical sociological analysis of motorcycling discourse through a feminist lens. I view gender as a relation that must constantly be (re)negotiated amongst socially constituted subjects and I pay particular attention to how technological discourse is made socially durable and sustainable by the interface of material (motorcycles) and organic (human) beings.
Longitudinal analysis of Cycle Canada illustrates the presence of heteronormative discourses that constrain readers' choices of gender identification and sexual orientation to traditional notions of masculinity. In an effort to create solidarity with their readers, the magazine editors cater to the perceived interests of an idealized male audience by performing these masculine identities. Though motorcycling culture in Canada is increasingly diverse, Cycle Canada has only begun to reflect this diversity in the past two years of publication. Explicating the social, political, economic, technological and historical context which gave rise to particular masculine identities in motorcycling culture allows us to focus on the positive agency involved in the performance of masculine identities, while still recognizing that there remains room to include other figurations of identity beyond traditional concepts of heteronormativity and homosociality.

abstract: M.A.


title: Social Competence and Collaborative Guided Inquiry Science Activities: Experiences of Students with Learning Disabilties

contributor:
Munby, Hugh
Education

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subject:
Collaborative Learning
Learning Disabilities
Elementary Science Education

abstract: Thesis (Ph.D, Education) -- Queen's University, 2008-04-14 20:05:55.867

abstract:
This thesis presents a qualitative investigation of the effects of social competence on the participation of students with learning disabilities (LD) in the science learning processes associated with collaborative, guided inquiry learning. An inclusive Grade 2 classroom provided the setting for the study. Detailed classroom observations were the primary source of data. In addition, the researcher conducted two interviews with the teacher, and collected samples of students’ written work.
The purpose of the research was to investigate: (a) How do teachers and peers mediate the participation of students with LD in collaborative, guided inquiry science activities, (b) What learning processes do students with LD participate in during collaborative, guided inquiry science activities, and (c) What components of social competence support and constrain the participation of students with LD during collaborative, guided inquiry science activities?
The findings of the study suggest five key ideas for research and teaching in collaborative, guided inquiry science in inclusive classrooms. First, using a variety of collaborative learning formats (whole-class, small-group, and pairs) creates more opportunities for the successful participation of diverse students with LD. Second, creating an inclusive community where students feel accepted and valued may enhance the academic and social success of students with LD. Third, careful selection of partners for students with LD is important for a positive learning experience. Students with LD should be partnered with academically successful, socially competent peers; also, this study suggested that students with LD experience more success working collaboratively in pairs rather than in small groups. Fourth, a variety of strategies are needed to promote active participation and positive social interactions for students with and without LD during collaborative, guided inquiry learning. Fifth, adopting a general approach to teaching collaborative inquiry that crosses curriculum borders may enhance success of inclusive teaching practices.

abstract: SSHRC

abstract: PhD


title: Low and high temperature performance of near surface mounted FRP strengthened concrete slabs

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

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abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2008-04-22 17:52:17.151

abstract: Near surface mounted (NSM) FRP reinforcement has recently emerged as a promising alternative technology for strengthening concrete structures in both flexure and shear, as opposed to externally bonded FRP strengthening systems.  Available research to date has focused primarily on overall member behaviour and/or the various parameters that affect the bond performance of either rectangular NSM strips or round NSM bars.  No research has apparently focused on the effect of low or high temperature exposure on NSM FRP performance.  It has been suggested by numerous researchers that NSM FRP reinforcement may outperform externally bonded FRP strengthening systems at elevated temperatures, but this assertion has yet to be supported by test results.  An extensive review of NSM FRP technology is presented.  The results of an experimental program conducted on twenty-three (23) concrete NSM FRP strengthened slab strips are presented to investigate their high (up to 200˚C) and low (-26˚C) temperature flexural performance.  The effect of using one of two different adhesive systems (epoxy and cement-based) and two different NSM groove widths (6.4 mm and 3.2 mm) is also studied.  An innovative photo imaging instrumentation technique is validated against traditional instrumentation techniques for the first time in NSM flexural testing.  A numerical layer model is presented and compared against test results. It is demonstrated that low temperature exposure has no measurable negative effects on the flexural performance of the slab strips tested.  From high temperature exposures, it is shown that the cementitious adhesive outperforms the epoxy adhesive system, allowing the strengthening system to remain structurally effective for more than 5 hours at 100°C under sustained loads.

abstract: M.Sc.


title: Mechanical Properties of Dynamic Energy Return Prosthetic Feet

contributor:
Bryant, J. Tim
Mechanical and Materials Engineering

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subject:
mechanical
properties
characterization
lower limb
feet

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-04-16 11:27:02.51

abstract:
The long-term goal of this study is to improve the ability of designers and prosthetists to match the mechanical characteristics of prosthetic feet to patient specific parameters, including, needs, abilities and biomechanical characteristics. While patient measures of performance are well developed, there is a need to develop a practical method by which non-linear and time-dependent mechanical properties of the prosthetic component can be measured. In this study, testing methodologies were developed that separately evaluated the elastic and time-dependent properties. Three styles of feet were tested to span the range of designs of interest: a standard solid ankle cushioned heel (SACH) foot, two energy return feet for active users and a new prosthetic foot designed to provide partial energy return.

The first testing regime involved mechanically characterizing prostheses under conditions similar to gait. The heels and toes of four sample feet were loaded to peak forces based on their design mass at a series of angles and forces that the prosthetic system would go through during the gait cycle, based on the waveform in ISO 22675. Tangential stiffnesses of the samples were determined using numerical differentiation. The force-displacement responses of prosthetic feet reflect increasing stiffnesses with increasing loads and a decreasing pylon angle. Key features reflecting foot design are: the relative stiffness of the heel and toe and the displacement gap at midstance. Stable feet tend to exhibit lower heel stiffnesses and higher toe stiffnesses, whereas dynamics energy return (DER) feet tend to exhibit higher heel stiffnesses and lower toe stiffnesses. The differences in heel and toe loading at midstance suggest that DER feet can aid in the transition from heel to toe, providing a smooth rollover whereas SACH feet provide greater stability.

A second testing regime examined the time-dependent properties of the heel and toe. A three-parameter reduced relaxation response of the form   was able to capture the force-relaxation characteristics with RMS differences ranging from 0.0006 to 0.0119. In this model, A is the initial decay, B is the decay coefficient, a linear decay term, and τ is a time constant. While the model is practical for comparing various prostheses at a single load level, a fully non-linear model is required to model the time-dependent response at all loading levels.

abstract:
Otto Bock®
Dupont
Niagara Prothetics and Orthotics International
Health Technology Exchange (HTX)
Ontario Centres of Excellence

abstract: M.A.Sc.


title: Loyal Subjects?: Consumer surveillance in the personal information economy

contributor:
Lyon, David
Sociology

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subject: Surveillance

subject: Consumption

subject: Branding

subject: Information and Communication Technologies

abstract: Thesis (Ph.D, Sociology) -- Queen's University, 2008-04-24 10:19:22.99

abstract:
This research examines loyalty marketing as an empirical case study of consumer surveillance. Focusing on the Canadian context, the research investigates the relationship between the personal information economy and loyalty marketing through several interrelated perspectives. These are marketing and business literature, theoretical frameworks of surveillance, the branding of consumers and corporations, consumer ambivalence towards surveillance and privacy issues, and the mutual shaping of consumers and these programs. These interrelated yet distinctive perspectives provide different means to understand loyalty programs as information portals in the increasingly monitored, measured and marketed lives of consumers. They are a means of surveillance through which corporations systematically collect consumption data in order to influence, manage, entitle, or control consumers (Lyon 2001).
The research is based on interviews with loyalty program executives, international survey results, and focus groups to both describe the relationship between corporate information processing and consumers as well as the current and potential social effects and issues embedded in this relationship. Loyalty programs are seen as an important means for conceptualizing contemporary marketing practices, the use of personal information, and personal identity in an information oriented society. They are a complex manifestation of a ‘knowing capitalism’ (Thrift 2005) that has implications far beyond the accumulation of points and the ‘reward yourself’ appeal of participation by contributing to a cultural consumption circuit that perpetuates and reinforces already existing socio-economic differences.

abstract: PhD


title: Psychedelic trips: travel and drugs in contemporary literature

contributor:
Varadharajan, Asha
English

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subject: Travel Drugs

abstract: Thesis (Ph.D, English) -- Queen's University, 2008-04-22 09:48:58.443

abstract:
This dissertation studies interlocking representations of travel and drugs in contemporary American, British, and Canadian novels, exploring how those thematics alternately destabilize and assuage subjectivity, genre, and the perception of space.  Following a prefatory chapter, Chapters Two and Three serve as a two-part introduction.  The first part articulates a theoretical lens I designate by enclosing the word “tripping,” a colloquialism for a drug experience, in quotation marks.  Through this lens, I examine travel and drugs in contemporary fiction indebted to sixties counterculture.  In Chapter Three, I examine the work of William S. Burroughs and Aldous Huxley, contextualizing their mid-twentieth-century travel and drugs as foundational to later twentieth-century “tripping.”

Chapter Four treats Huxley’s novel, Island, as a revision of the foundations I outline in the previous chapter; his instantiation and critique of utopia via “tripping” help conceptualize the psychedelic experience as protective spatial movement – physical mobility instead of psychedelic fungibility – in the service of preserving a stable sense of self.  Chapter Five discusses Alex Garland’s The Beach, in which drugs reveals the limitations of utopian thought by underscoring the paradoxical notion of immobility hidden within the supposed freedom of mobility.  In these novels, Huxley and Garland depict travel as a key to the process of rendering psychedelic intoxication knowable in familiar terms.

Chapters Six and Seven, in exploring Hunter S. Thompson and Robert Sedlack, shift toward defamiliarizing conventional modes of travel using some of the radical possibilities of drug intoxication.  Chapter Six examines Fear and Loathing in Las Vegas, a text which, instead of attempting to understand inassimilable drug experiences by spatializing the drugged mind, explores mind-alteration as a way of understanding the postmodern space of Las Vegas that emerges following the demise of the counterculture.  Chapter Seven constructs a reading of Sedlack’s The African Safari Papers, examining ways its representation of self-conscious tourism, inflected by intoxication and Thompson-inspired excess, deploys the figures of the shaman and of animals to complicate conventional understandings of tourism.  Thompson and Sedlack explore how the subjectivities of domestic and global tourists are reshaped by, rather than resist, the radical alterity introduced by the drug experience.

abstract: Queen's University; Ontario Graduate Scholarship

abstract: PhD


title: Molecular cloning and characterization of the allatostatin receptor in the cockroach Diploptera punctata

contributor:
Bendena, William G.
Biology

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subject:
Allatostatin
Allatostatin receptor
Juvenile hormone
RNAi

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2008-04-22 15:21:55.107

abstract:
Allatostatins (ASTs) are neuropeptides that inhibit the biosynthesis and release of juvenile hormone from the corpora allata (CA) of various insects including the cockroach Diploptera punctata. We hypothesized that a similar allatostatin receptor would exist in the cockroach D. punctata that may regulate the numerous physiological effects that this family of peptides exerts on a range of target tissues. Using polymerase chain reaction (PCR) strategies successful in isolating other insect allatostatin receptor sequences utilized primers designed to known mammalian somatostatin receptors and Drosophila allatostatin receptor (AlstR). Once an internal PCR fragment was proven to be consistent with the sequence of an allatostatin receptor (AstR) then the sequence was completed by rapid amplification of cDNA ends (RACE). The putative allatostatin-like receptor sequence encoding 425 amino acid residues was isolated from a cDNA library prepared from corpora allata of D. punctata.

We show that dsRNA targeting the allatostatin receptor gene of D. punctata injected into freshly moulted adult cockroaches produced a long-lasting reduction in the mRNA levels in midgut tissues. The effect lasted up to 6 days. Following dsRNA injection, the juvenile hormone (JH) titers in the corpora allata were clearly raised suggest that the putative inhibition of receptor RNA expression may increase JH production.

The receptor is expressed in brains, corpora allata, abdominal ganglion, midguts, ovaries, and testes. We have examined these same tissues with regard to changes in expression levels of Dippu-AstR. JH biosynthesis peaks on day 5 post-emergence in mated females. In mated females, Dippu-AstR mRNA is expressed at the highest levels on day 6 post-emergence in brain and corpora allata and day 2 post-emergence in midgut. Dippu-AstR is likely responsible for the decline in JH biosynthesis after day 5 post-emergence. Virgin females midgut and CA Dippu-AstR mRNA expression dramatically elevated on days 6 and 7, respectively. Expression of Dippu-AstR was similar in the abdominal ganglia of mated or virgin females. Ovarian Dippu-AstR expression declines to low levels by day 4. Testes also express peaks of Dippu-AstR expression on days 4 and 7. A role for Dippu-AST in testes is yet unknown.

abstract: PhD


title: The influence of blasting on Kemess hypogene ore milling

contributor:
Katsabanis, Panagiotis (Takis) D.
Mining Engineering

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subject: Mining Comminution Blasting

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2008-04-22 21:18:04.939

abstract:
Traditionally, optimization of drill and blast practices have taken place with sole respect to minimizing mine unit cost (as opposed to the operation as a whole), whilst maintaining fragmentation at a level that is considered “acceptable” to mine operations.  Judgments as to “acceptable” are largely based on qualitative measures and the consequences of varying blast practices on subsequent downstream processes are secondary.  The objective of this work was to evaluate both the technical and economic consequences of blast practices on comminution processes at the Kemess South Project.  Computer modeling indicates that without changes to crusher operating parameters, there does not appear to be much room for improving the performance of the comminution circuit.  This indicates that current blasting at the mine is at or near optimal for the mill’s current configuration.
Experiments to attempt to detect the effect of blasting on the crushability and grindability of rock were carried out on several different samples, including a copper-gold porphyry ore from Kemess Mine, taconite from Minnesota, granodiorite from the Kingston area, and limestone from the Kingston area. The main focus of this study was the Kemess ore.  Examining rock samples from blasted and un-blasted ore, the samples that were blasted showed a significant increase in the density of very small cracks within individual fragments, which would indicate that they should break more easily during crushing and grinding.  Drop-weight impact tests investigating the grindability of these samples suggested that there was improved performance with blasting effort, although the difference between some samples was not statistically significant. Preliminary testing of the taconite and the limestone indicated that crushability and grindability may be improved by blasting.
Using mineral processing simulation software, the second part of the study investigated the effects of changing the ore size distribution that is fed to the Kemess Primary crusher.  It was concluded that the Kemess Semi-Autogenous Grinding (SAG) mill throughput could be increased by increasing fragmentation and making adjustments to the primary crusher closed side set to take advantage of the increased fragmentation.  These changes were calculated to be economically advantageous.

abstract: Kemess Mines Ltd., MinnovEX Technologies Inc.

abstract: M.A.Sc.


title: The challenges and complexities of initiating a professional learning community of teachers

contributor:
Russell, Tom
Education

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subject: Learning Community

subject: Collaboration

subject: Teacher Community

subject: Challenges of a Teacher Learning Community

subject: Caribbean School

abstract: Thesis (Ph.D, Education) -- Queen's University, 2008-04-23 13:41:46.823

abstract:
This is a case study of the challenges and complexities of initiating a professional learning community of teachers.  Situated in a school in the British West Indies, this study draws on the experiences of seven teachers initiating a professional learning community (PLC) over a 12-week term in 2007.  Individual interviews, group meetings, journal entries, and exit comments were analyzed to construct five main themes: Initiating a PLC, Features of a PLC, Challenges of a PLC, Benefits of a PLC, and the Future of the PLC.
These teachers recognized the need for this community because of challenges and problems they faced.  Many features reported in the literature on PLCs were present in this nascent PLC of teachers.  The teachers created their own shared vision and provided evidence of collective learning in the weekly meetings.  Participants developed trust and shared many personal practices and experiences of teaching.
Challenges to initiating a professional learning community included finding time to meet, a weak school culture, and barriers associated with immigration status.  Despite the challenges, there were many perceived benefits, including saving time through subject integration, personalizing professional development, and increasing socialization to reduce teachers' sense of professional isolation.  The teachers also displayed changes in attitudes towards teaching and how they approached teaching their classes.  Classes became more student-centred as teachers tried to meet the diverse needs of their students.  The promise of increased collaboration and membership at the conclusion of data collection failed to materialize when a new leader did not come forward.

abstract: PhD


title: Promoting evaluation use within  dyamic organizations: a case study examining evaluator behaviour

contributor:
Shulha, Lyn
Education

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subject:
Evaluation
Case study

abstract: Thesis (Ph.D, Education) -- Queen's University, 2008-04-23 13:48:32.287

abstract:
In this thesis I describe a research study to further our understanding of the role of the evaluator as a facilitator of evaluative inquiry within organizations. I assumed dual roles as both the evaluator and the evaluation-use researcher to examine the effect of my behaviour on the evaluation of a dynamic organization. My approach as the evaluator was influenced by a decade of experience as a practising evaluator and by the insights I gained from my readings of organizational theory and three evaluation theories responsive, participatory, and developmental.

My study of the nature, quality, and consequences of the evaluator/stakeholder interactions while participating in the process was anchored by approaches from the fields of educational research and organizational theory informed by complexity science. Using data generated from modifying the traditional case study method, including reflective journal entries related to my decision-making process, I generated critical episodes as a way of understanding the circumstances surrounding shifts in my behaviour. My iterative analysis of the critical episodes and the insights gained from them enabled me to track the transformations of the six personal evaluation principles that guided my evaluator approach and led to the creation of a seventh principle. The cross-case analysis revealed the evaluation process as a non-linear progression whereby the evaluator and the individual stakeholders engaged in establishing trust, fostering collaborations, and promoting learning.

This study contributes three implications for evaluation practice including providing empirical data on what it means for an evaluator and individual stakeholder to develop close engagement through evaluative inquiry, bringing to the forefront the value of systematic and purposeful reflection as a means of enhancing the quality of this engagement, and pointing to the importance for evaluators continually integrating past experiences and new theoretical frameworks with understandings gleaned from close engagement. Finally, I posit a new approach documenting the complexity of the influence of the evaluator on shaping organizational and program development within the dynamic context.

abstract: PhD


title: An experimental study of a compact autothermal gasoline reformer for the producation of hydrogen

contributor:
Oosthuizen, Patrick H.
Peppley, Brant A.
Mechanical and Materials Engineering

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subject:
Autothermal reforming
Isooctane

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-04-23 17:14:46.198

abstract:
The experimental analysis of an autothermal gasoline reformer for use in an auxiliary power unit was undertaken. The development of these auxiliary power units has the potential to create positive economical and environmental benefits. It will provide the necessary energy and heating while utilizing a fuel with a well established infrastructure. Autothermal reforming is a process in which both oxygen and steam are
combined with a hydrocarbon fuel over a catalyst bed in order to produce a hydrogen rich gas stream. This process utilizes an exothermic partial oxidation reaction to promote the hydrogen efficient, endothermic steam reforming reaction. The main goals of this study were to design and test the operating conditions of a new autothermal reformer and to determine an operational envelope for the reactor. Furthermore, the data collected was used to validate a numerical model of the reactor that would assist in the development of future compact autothermal reformers.

A compact autothermal reformer has been designed with the capability to produce
detailed wall and centerline temperature profiles during operation. During the
experimental phase of this project, a strong relationship between the main input variables
(the oxygen to carbon and steam to carbon ratios) and the performance characteristics of the reactor was found. For the range of experimental conditions tested, the highest molar percent of hydrogen in the reformate for a gas hourly space velocity of 20,000h-1 was found at an oxygen to carbon ratio of 1.0 and a steam to carbon ratio of 2.0. Performance characteristics used for the reactor were the lower heating value, the percent hydrogen yield and fuel conversion, and were found to have maximum values of 46.0%, 47.6% and 67.7% respectively. Carbon deposition on the catalyst bed was found to be significant under certain operating conditions, but had a very small effect on the final conditions of the ATR. The computational fluid dynamics model was shown to have fairly accurate predictions for the temperature profiles as well as the reformate compositions when compared to the experimental data. A number of recommendations have been made to the experimental and numerical studies. It is likely that if employed in future testing,
they would improve the overall performance of the compact autothermal reformer.

abstract: M.A.Sc.


title: Their capacity to delight: knowing persons with dementia through haiku

contributor:
Luce-Kapler, Rebecca
Education

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subject:
Arts education
Dementia care
Haiku

abstract: Thesis (Master, Education) -- Queen's University, 2008-04-24 09:27:30.949

abstract:
This research explores the use of haiku poetry to connect with persons with dementia. The happenings during two one-hour sessions provide the main focus for this study. These sessions were part of an ongoing spiritual care program on the secure dementia unit of a long-term care facility. The sessions were co-facilitated by the chaplain who leads the ongoing program, and by myself as both guest poet and researcher. Haiku were used as prompts to reminiscence. Words and phrases from the stories that were spoken during the session became the building blocks for creating collaborative haiku within the group setting.

“Inferences all over” was spoken by a person with severe dementia and became a part of one of the collaborative haiku. This comment is remarkable for its association to poetry where the words on the page often only hint indirectly at a deeper meaning, and for its association to spirituality where the stories we tell often only hint at our deeper truth. The ambiguity around what is evident and what is implied paradoxically invites connection. The first chapter of this thesis, Beginning, describes the format of a haiku session where building connection is the primary intention. It also explores issues around the creative arts.

“Inferences all over” also speaks to the hermeneutic phenomenological approach of this thesis, where the stories speak for themselves. These stories appear in the second chapter entitled During, along with insights gleaned from interviews.

“Inferences all over” well describes the third chapter, After, where I reflect on my experiences as a participant in this research, and where I detail some of the ripples of this study into the dementia care, haiku, and educational communities.

“Their capacity to delight” in the thesis title was spoken by the chaplain who developed the spiritual care program. Her belief in the possibility of connection with persons with dementia forms the bedrock of the program—where hospitality invites connection and validation affirms their responses. This capacity has implications for all teaching—formal as well as informal—as it invites learning as an experience to enjoy rather than endure.

abstract: M.Ed.


title: Surrogate decision making for the critically ill intensive care unit patient

contributor:
Baker, Cynthia
Heyland, Daren
Lamb, Marianne
Nursing

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subject:
End of life
Intensive care unit
Decision making

abstract: Thesis (Master, Nursing) -- Queen's University, 2008-04-25 09:29:27.1

abstract:
The technological complexity of the ICU is often focused on saving lives however, it is frequently a place to support the dying. Because of the serious nature of critical illness, patients are unable to communicate their wishes, values and views.  Family members are often called upon to communicate the critically ill patients’ wishes and many report feeling burdened with the task. The distress described may lead to difficulty mobilizing coping mechanisms and may affect their ability to make appropriate decisions for their family member’s care.  Hence, an in depth understanding of the surrogate’s experience is critical to plan effective interventions and provide anticipatory guidance to support the process of making decisions around end of life care.
Objective The purpose of the study is to describe the surrogate decision makers’ appraisals of the demands of decision making for a critically ill adult intensive care unit patient and the coping strategies employed by them during this experience.
Method A descriptive study design using a qualitative interviewing approach extracted perceived stressors and coping strategies using systematic, focused thematic analysis guided by Folkman and Lazarus’ Stress and Coping Paradigm.
Findings Respondents appraisals identified the following perceived stressors: doubt of self efficacy, unknowns, impingement of real life, and problematic relay of information.  The surrogates’ perception of their ability to manage the decision making process required their awareness of the decision making role and magnitude of illness, their need to form partnerships, time to reflect on prior discussions and experience, and their appraisal of the patients’ suffering.  Participants described emotion and problem based coping strategies they employed during the task.  To emotionally justify their decisions, surrogates’ referred to their understanding of patient wishes and sought solace and comfort from the health care staff.  In addition, surrogates used strategies to solve problems encountered including dealing with others, employing strategies to decrease their uncertainty and mobilizing time to process the events unfolding.
Conclusions End of life decisions in the intensive care are complex and demanding. A better understanding of the process may guide health care professionals in developing focused interventions to assist surrogates through a painful process.

abstract: MNSc.


title: Identity re/construction of cross-cultural graduate students

contributor:
Krugly-Smolska, Eva
Education

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subject:
Identity Construction
Cross-Cultural
Education
English as a Second Language
Personal Identity
Writer Identity
Additional Culture
Additional Language
Mediated Space
Mediated Self
Academic Writing
Academic Culture
Ambiguity
Differences
Mediation
Interpretive Research

abstract: Thesis (Ph.D, Education) -- Queen's University, 2008-04-24 23:24:36.208

abstract: This research explores the identity reconstruction of graduate students in additional language (AL) contexts. It addresses not only the issue of language proficiency in self-representation, but also more complicated factors that influence self-positioning and perceived social positioning in an additional culture, as well as ways of establishing the self in academic writing. The research is grounded in language learning theories in second language education and identity theories in linguistics, sociology, and cultural studies. Eleven graduate students participated in the study, among whom five were international students at a Chinese university and six were Chinese students at a Canadian university. Data were drawn from a questionnaire, writing samples, interviews, and email correspondence. Commonalities and divergences were found between groups and within groups. I developed a framework of writer identity for AL graduate students prior to the study and modified it in the discussion. Based on the data, I elaborated on the connections of personal identity and writer identity, and conceptualized for AL speakers a mediated space incorporating home culture and host culture but going beyond the overlap of the two, as well as a mediated self that is achieved through negotiation with the available options in their respective social context.

abstract: PhD


title: Pulse shape discrimination studies in liquid argon for the DEAP-1 detector

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subject:
DEAP
Dark matter
Argon
Scintillation

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2008-04-25 01:39:39.121

abstract: A detector with a target mass of 7 kg of liquid argon was designed, constructed and operated at Queen’s University. This detector is a scaled model for the DEAP project toward a tonne-scale argon detector to search for the WIMP candidate of the so far undetected, dark matter of the universe. The primary intent of the scaled detector was to measure the achievable level to reject background events by use of pulse shape discrimination, being based upon the scintillation timing properties of liquid argon. After refining the apparatus and components, the detector was in operation from the 20th of August until the 16th of October 2007 before being moved to its current location in SNOLAB. During this time, a population of 31 million well-tagged gamma events were collected, of which 15.8 million were in the energy range of interest for calibration. This population was sufficient to demonstrate the discrimination of background events by pulse shape discrimination at the level of 6.3 × 10-8. An analytical model was constructed, based on the scintillation processes and detector response, and has been sufficiently investigated to make predictions of further achievable discrimination.

abstract: M.Sc.


title: Conformal Radiation Therapy with Cobalt-60 Tomotherapy

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subject:
Radiation Therapy
Conformal radiation therapy
Tomotherapy
Cobalt-60 tomotherapy
IMRT

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2008-04-25 02:20:56.102

abstract:
Intensity-modulated radiation therapy (IMRT) is an advanced mode of high-
precision radiation therapy that utilizes computer-controlled x-ray accelerators to
deliver precise radiation doses to malignant tumors. The radiation dose is designed to
conform to the three-dimensional (3-D) shape of a tumor by modulating the intensity
of the radiation beam to focus a higher radiation dose to the tumor while minimizing
radiation exposure to surrounding normal tissue. One form of IMRT is known as
tomotherapy. Tomotherapy achieves dose conformity to a tumor by modulating the
intensity of a fan beam of radiation as the source revolves about a patient.
Current available tomotherapy machines use x-ray linear accelerators (linacs)
as a source of radiation. However, since linacs are technologically complex, the world-
wide use of linac-based tomotherapy is limited. This thesis involves an investigation
of Cobalt 60 (Co-60) based tomotherapy. The inherent simplicity of Co-60 has the
potential to extend the availability of this technique to clinics throughout the world.
The goal of this thesis is to generate two-dimensional (2-D) Co-60 tomotherapy con-
formal dose distributions with a computer program and experimentally validate them
on ¯lm using a ¯rst generation bench-top tomotherapy apparatus.
The bench-top apparatus consists of a rotation-translation stage that can
mimic a 2-D tomotherapy delivery by translating the phantom across a thin, "pencil-
like" photon beam from various beam orientations. In this thesis, several random and
clinical patterns are planned using an in-house inverse treatment planning system and
are delivered on ¯lm using the tomotherapy technique. The delivered dose plans are
compared with the simulated plans using the gamma dose comparison method. The
results show a reasonably good agreement between the plans and the measurements,
suggesting that Co-60 tomotherapy is indeed capable of providing state-of-the-art
conformal dose delivery.

abstract: Canadian Institutes of Health Research (CIHR) and the ORDCF’s Ontario Consortium for Image-guided Therapy and Surgery.

abstract: M.Sc.


title: Estimation of Free Radical Polymerization Rate Coefficients using Computational Chemistry

contributor:
Hutchinson, Robin A.
Chemical Engineering

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subject:
Quantum Chemistry
Radical Polymerization
Reactivity Ratios
Conformation Optimization
Kinetics (polym.)

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2008-04-25 16:13:12.091

abstract:
Acrylic free radical polymerization at high temperature proceeds via a complex set of mechanisms, with many rate coefficients poorly known and difficult to determine experimentally.  This problem is compounded by the large number of monomers used in industry to produce coatings and other materials.  Thus, there is a strong incentive to develop a methodology to estimate rate coefficients for these systems.  This study explores the application of computational chemistry to estimate radical addition rate coefficients for the copolymerization of acrylates, methacrylates and styrene.

The software package Gaussian is used to calculate heats of reaction (ΔHr) values for monomer additions to monomeric and dimeric radicals, using minimum energy structures identified and characterized for the reactants and products.  The Evans-Polanyi relationship is applied to estimate reactivity ratios from the relative differences in ΔHr.  The validity of this methodology is tested through a comparison of calculated monomer and radical reactivity ratios for acrylate, methacrylate, vinyl acetate, ethene and styrene systems to available experimental data for copolymerization systems. The methodology is found to work for some systems while there is computational breakdown in others due to steric crowding and/or breakdown of the Evans-Polanyi relationship.

abstract: NSERC

abstract: PhD


title: Political Parties and Democratic Development in Ghana: From Transition to Consolidation and Beyond

contributor:
Conaghan, Catherine
Banfield, Bruce
Political Studies

subject:
Ghana
Democracy
Political Parties
Transition
Consolidation

abstract: Thesis (Ph.D, Political Studies) -- Queen's University, 2008-04-25 12:19:43.574

abstract:
At the time of the Ghana’s independence in March 1957, a democratic system of government was instituted, but the process of political development was derailed and often interrupted by frequent coups. This is evident in the interchange of military and civilian regimes in the last fifty-one years. While in the post-independence era, the development of democracy, the party system and democratic institutions in Ghana has taken many twists and turns due to the persistent military interventions in politics, as part of the third-wave of democratization, in 1992, under Ghana’s Fourth Republic, a new democratic system was re-introduced in the country under the National Democratic Congress (NDC) government.  The opening of political spaces for the political parties and civil society organizations in the last two decades has witnessed the resurgence of political parties of different sizes and ideological orientation under various political traditions, which has led to the strengthening of Ghana’s party system.
This, in turn, has immensely facilitated the country’s democratic development, which was evidenced in the 2000 power alternation that led to the election of the New Patriotic Party (NPP) to power. Since the emergence of the third-wave of democratization, there have been numerous theoretical approaches by democratic transition and consolidation theorists on the role of political parties in the nurturing and consolidation of democracy in the third-wave countries. This study examines the internal organization of parties and their role in Ghana’s democratic transition and consolidation. On the basis of the evidence presented in this study, it can be concluded that while the political parties have been the bedrock for Ghana’s democratic transition and consolidation processes, there are a number of key issues such as internal party democracy and candidate selection processes that needed to be resolved by the political parties in order to strengthen Ghana’s democratic consolidation process.

abstract: PhD


title: Small Proline Rich Protein-2 Expression and Regulation in the Caco-2 model of Intestinal Epithelial Differentiation along the Crypt-Villus Axis

contributor:
Ropeleski, Mark
Anatomy and Cell Biology

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subject:
Small Proline Rich Proteins
Western Blot
Confocal Microscopy
Salmonella Typhimurium
GPR41/43
Short Chain Fatty Acids
Protein Kinase A
Differentiation

abstract: Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2008-04-25 12:39:06.427

abstract:
Small proline-rich protein-2 (SPRR2) functions as a determinant of flexibility and permeability in the mature cornified envelope of the skin. SPRR2 is strongly upregulated by the commensal flora and may mediate signaling to differentiated epithelia of the small intestine and colon. Yet, SPRR2 function in the GI tract is largely unexplored. Using the Caco-2 model of intestinal epithelial differentiation along the crypt-villus axis, we hypothesized that SPRR2 would be preferentially expressed in post-confluent differentiated Caco-2 cells and examined SPRR2 regulation by the protein kinase A pathway (PKA) and short chain fatty acids (SCFAs).
Differentiation-dependent SPRR2 expression was examined in cytoskeletal-, membrane-, and nuclear-enriched fractions by immunoblotting and confocal immunofluorescence. We studied the effect of SCFAs, known inducers of differentiation, on SPRR2 expression in pre-confluent undifferentiated Caco-2 cells and explored potential mechanisms involved in this induction using MAP kinase inhibitors. SPRR2 expression was also compared between HIEC crypt cells and 16 to 20 week primary fetal villus cells as well as in different segments in mouse small intestine and colon. We determined if SPRR2 is increased by gram negative bacteria such as S. typhimurium.
SPRR2 expression increased in a differentiation-dependent manner in Caco-2 cells and was present in human fetal epithelial villus cells but absent in HIEC crypt cells. Differentiation-induced SPRR2 was down-regulated by 8-Br-cAMP as well as by forskolin/IBMX co-treatment. SPRR2 was predominantly cytoplasmic and did not accumulate in Triton X-100-insoluble cytoskeletal fractions. SPRR2 was present in the membrane- and nuclear-enriched fractions and demonstrated co-localization with F-actin at the apical actin ring. No induction was seen with the specific HDAC inhibitor trichostatin A, while SCFAs and the HDAC inhibitor SBHA all induced SPRR2. SCFA responses were inhibited by MAP kinase inhibitors SB203580 and U0126, thus suggesting that the SCFA effect may be mediated by orphan G-protein receptors GPR41 and GPR43. S. typhimurium induced SPRR2 in undifferentiated cells.
We conclude that SPRR2 protein expression is associated with differentiated epithelia and is regulated by PKA signaling and by by-products of the bowel flora. This is the first report to establish an in vitro model to study the physiology and regulation of SPRR2.

abstract: This work was funded by the CIHR GIDRU Training Grant and Aid in Research from Crohn's and Colitis Foundation of Canada

abstract: M.Sc.


title: Strategic Design of an Underground Mine under Conditions of Metal Price Uncertainty

contributor:
Pelley, Charles
Mining Engineering

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subject:
production rate
cut-off grade
metal prices
underground mine

abstract: Thesis (Ph.D, Mining Engineering) -- Queen's University, 2008-04-25 12:42:24.623

abstract:
Long-term mine plans are based on forecast future metal prices. By the time the development is put in place, the forecasts may have been proved wrong and the production plan might not meet the company's financial objectives. At that point, the common reaction to this situation is to create a new revised long-term plan and spend more capital, only to find out at a later time that the metal prices have changed again. This results in an inefficient use of capital with low returns to the investors.

The objective of this thesis is to develop a methodology to determine the cut-off grade and production rate of a narrow-vein underground mine such that the long-term strategic plan is robust.  As a requirement to do so, it is necessary to have a good understanding of the resources, revenues, capital and operating costs as a function of the design parameters.  Also, the operational limits of the mine must be determined so that the solution is practical.  Afterwards, annual metal prices are randomly generated with a Monte Carlo process on stochastic metal price models, and the combination of production rate and cut-off grade yielding the highest net present value is identified and recorded. This process is repeated many times, and the probabilities of the solutions occurring at any given design combination are calculated.  The results are plotted on a bubble graph, where the size of a bubble is directly proportional to the probability a solution occurs at that point.  Finally, the combination with the largest bubble is the solution, as this point has the highest probability of yielding the highest net present value in most circumstances.

The model was first tested on an actual gold-copper orebody where very detailed resource and cost information was available.  The methodology was applied with success and the solution reflected the important impact of the copper milling and roasting process on revenues.  Other tests were then done on a hypothetical gold orebody and the results showed a great degree of sensitivity to the average grade of the deposit.

abstract: PhD


title: Activation of EPAC Inhibits the Aquisition of Nucleus Accumbens Amphetamine Place Preference in a Dose-Dependent Manner in Rats

contributor:
Beninger, Richard J.
Neuroscience Studies

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subject:
dopamine
reward
reward-related learning
addiction
conditioned place preference
place conditioning
cAMP
PKA
Epac
intracellular signalling
Sp-cAMPS
8-pCPT
amphetamine
nucleus accumbens

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2008-04-25 13:29:37.857

abstract: Reward-related learning occurs when previously neutral stimuli acquires an enhanced ability to elicit approach and other responses. Studies in the past have shown that dopamine receptor-mediated 3’,5’-cyclic adenosine monophosphate (cAMP)-dependent intracellular signalling is important for reward-related learning. Until recently, cAMP-dependent protein kinase (PKA) was the only known signalling molecule that was activated by cAMP. However, it has been discovered that another enzyme, exchange protein directly activated by cAMP (Epac), is also activated by cAMP. Thus, it is possible that cAMP mediates reward-related learning by an Epac-dependent signalling pathway. The present study used a conditioned place preference (CPP) paradigm to investigate whether Epac is involved in the acquisition of reward-related learning. Bilateral injections of amphetamine (20 µg/0.5μl/side) into the nucleus accumbens (NAc) have been shown in previous studies to reliably produce a CPP. Thus, amphetamine (20 µg) and Sp-adenosine 3’,5’-cyclic monophosphorothioate triethylamanine (Sp-cAMPS) (0.1, 1.0, 10, 15, 20 µg), an agent that activates both PKA and Epac, or amphetamine (20 µg) and 8-(4-chlorophenylthio)-2’-O-methyladenosine-3’,5’-cyclic monophosphate (8-pCPT) (0.73, 1.27, 1.45, 2.89, 5.78, 11.56 µg), an agent that selectively activates Epac, were co-injected into NAc to determine their effects on the acquisition of CPP. Results showed that 8-pCPT (1.45 µg), but not lower or higher doses, inhibited CPP. Sp-cAMPS (0.1, 15, 20 µg) also inhibited CPP, replicating the results of previous studies. The results implicate Epac in the acquisition of reward-related learning.

abstract: M.Sc.


title: An Investigation of Nano-voids in Aluminum by Small-angle X-ray Scattering

contributor:
Diak, Bradley J.
Singh, Marsha A.
Mechanical and Materials Engineering

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subject:
SAXS
aluminum
nano-voids
vacancy clustering

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-04-25 15:17:30.211

abstract: Small angle x-ray scattering (SAXS) with synchrotron radiation was used to characterize nano-sized voids in different nominally pure aluminum (Al) alloys produced by quenching.  The scattering signal from nano-voids is shown to be predictable from SAXS theory, and the information related to the void population confirm past experiments and reveal new details about quench-void formation in Al.  Specifically, voids were produced in 99.97 at.% to 99.9994 at.% Al alloys by infrared heating to 450 – 625 °C followed by controlled rapid quenching at 10^3 to 10^5 °C/s.  For changing processing conditions, the size of voids varied between 5 to 11 nm, and the density of voids varied by over an order of magnitude.  Results from SAXS were consistent with TEM observations performed on the same specimens, indicating that synchrotron SAXS can be reliably used to characterize nano-voids produced in quenched Al.  Factors determined to affect voids were consistent with previous studies, except that the present nano-voids dissolved after only 3 min. at 145 °C, indicating that quenched nano-voids are less stable than previously determined.  SAXS also showed that void size is sensitive to quench temperature and quench rate.  The activation energies for void nucleation and growth were determined to be 0.75 ± 0.10 and 0.19 ± 0.03 eV/at., respectively, confirming that hydrogen and di-vacancies take part in nucleation and growth during quenching.  It was concluded that the non-linear tail of the quench curve plays a crucial role in void formation, and that voids form when long range diffusion is inhibited.  This information can be utilized to design new Al alloys that limit incipient void formation, which is detrimental to properties such as formability.

abstract:
Natural Sciences and Engineering Research Council of Canada;
General Motors of Canada Limited

abstract: M.A.Sc.


title: Does Mental Practice Promote Cortical Reorganization and Improved Hand Function in Stroke?

contributor:
Brouwer, Brenda
Rehabilitation Science

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subject:
Mental Practice
Stroke
Transcranial Magnetic Stimulation

abstract: Thesis (Master, Rehabilitation Science) -- Queen's University, 2008-04-25 16:23:51.775

abstract: The upper extremity is often left with permanent disability following stroke and therapeutic techniques used at present have had limited success. This prospective clinical trial evaluated the effectiveness of mental practice (MP) through motor imagery (MI) a therapy technique to enhance upper extremity motor recovery after stroke. MI ability, upper extremity hand function, finger strength, and motor cortical output were examined in 18 stroke subjects (mean 67.5 years). Subjects were randomly allocated to the MP treatment group or the control group which received cognitive therapy. Both groups received their respective treatment daily for 30 minutes for a 3 week period. Assessments were performed prior to treatment, post treatment and at 3 months post treatment. Imagery ability was measured using the Kinesthetic and Visual Imagery Questionnaire (KVIQ) and mental chronometric testing. Hand function was assessed with the box and block test (BBT) and finger strength with maximum voluntary contraction (MVC). To determine the effect of MI on neural excitability, focal transcranial magnetic stimulation was applied over the primary motor cortex while participants were at rest and while they imagined themselves performing abduction of the index finger. Motor evoked potentials were recorded from the contralateral first dorsal interosseous (FDI), abductor digiti minimi (ADM) and abductor pollicis brevis (APB) muscles. Data were analyzed using multifactor and repeated measures ANOVAs with the significance level set to p < 0.05.  Results showed no significant difference between groups on any of the outcome measures (p > 0.05) although all subjects improved their hand function over the study period (p < 0.05). In addition, motor threshold was found to decrease over time (p < 0.001) in all subjects demonstrating improvement in cortical motor excitability and output. Motor evoked potentials (MEPs) elicited during MI were significantly larger compared to those evoked at rest (p < 0.022). MEP amplitudes from FDI, the muscle targeted with MP, showed a significant interaction effect between time and group (p = 0.021) which reflected an increase in MEPs in the MP group over time whereas a decline occurred in the cognitive group. These findings indicate that MI enhances motor cortical output in stroke and that MP using MI appears to increase corticospinal output to the target FDI muscle. No differential effects of MP and cognitive therapy interventions were evident in terms of hand function and finger muscle strength.

abstract: Heart and Stroke Foundation

abstract: M.Sc.