title: Molecular Dynamics Simulations and Flow Injection Studies of Hydrothermal Fluids

contributor:
Svishchev, Igor M.
Chemistry

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subject:
hydrothermal
molecular dynamics
flow injection

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2009-03-05 17:39:30.197

abstract:
Hydrothermal fluids near and above the critical point of water have unique and potentially very useful thermophysical properties. At present, the lack of knowledge of supercritical water chemistry hinders implementation of innovative hydrothermal technologies. The development of new experimental methods and application of molecular modeling tools is clearly warranted to provide a better understanding of the complex properties of aqueous systems at elevated temperatures and pressures.
The thermodynamic, dielectric and transport properties of hydrothermal fluids are investigated using Molecular Dynamics (MD) simulation and flow injection techniques. The spatial hydration structures and self-diffusion coefficients of phenol, aniline and naphthalene in aqueous infinitely dilute solution are examined from ambient to supercritical conditions by means of MD simulations. It is shown that the solvation shell around aromatic molecules undergoes significant changes along the liquid-vapour coexistence curve and, essentially, disappears at supercritical conditions. The changes in hydration structures are reflected in the values of the self-diffusion coefficients which dramatically increase near the critical point of water. The thermodynamic and dielectric properties of the Simple Point Charge Extended (SPC/E) water model are examined over a broad range of sub- and supercritical states. Accurate thermodynamic and dielectric equations of state (EOS) for the SPC/E water model are presented. The parameterizations provide the most accurate, up-to-date description of the properties of high-temperature SPC/E water, thus enabling for the direct comparison of molecular simulation results with experimental data via the corresponding states principle.
The experimental methodology for the study of aqueous fluids at extreme conditions by using the ex situ flow injection technique is presented. The methodology significantly simplifies the technical aspects of flow injection analysis in hydrothermal fluids as sample injection and detection are performed at ambient temperature, thus allowing the use of standard on-line detection methods. The proposed ex situ experimental technique is applied to the examination of the hydrodynamic regime of a flow-through tubular reactor from ambient to supercritical water conditions. Application of the ex situ Taylor dispersion technique to measurements of the binary diffusion coefficients in hot compressed water is also presented. The ex situ flow injection methodology provides a basis for further development of flow injection analysis techniques at supercritical water conditions.

abstract: PhD


title: Effects of Intermittent Static and Dynamic Tension on Articular Chondrocytes in High Density Culture

contributor:
Waldman, Stephen D.
Mechanical and Materials Engineering

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

subject: Biomechanical Engineering

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-03-05 18:06:46.925

abstract:
Tissue engineering has the potential of becoming an effective approach for the replacement of articular cartilage.  However, the problems of small tissue size and inadequate mechanical properties of the tissue have yet to be overcome.  Mechanical stimulation of cartilaginous tissues is one method of accelerating chondrocyte proliferation and ECM synthesis.  While the effects of compression and shear have been well studied, the effects of tension have received little attention.  Based on the findings of previous mechanical stimulation studies and photographic evidence of tension acting in native articular cartilage in its physiological environment, it was hypothesized that intermittent applications of tensile strain can be used to stimulate cellular proliferation and ECM synthesis and thereby improve the size and mechanical properties of cartilaginous tissues.

A loading fixture was constructed to apply biaxial tensile strains (BTS) to cartilaginous tissues grown in vitro.  The optimal conditions for stimulating proliferation and ECM synthesis were found to be static tension (as opposed to dynamic tension), 3.8% radial and 2.1% circumferential strain magnitude for a 30 minute duration.  Tissues subjected to BTS stimulation for 4 weeks at a frequency of once every 2-3 days had increased thickness, wet weight, and proteoglycan content, but had little effect on tissue mechanical properties.  Tissues stimulated at a frequency of once per day over the same period had a negligible effect.  A subsequent experiment confirmed that the effects of BTS stimulation on proliferation and ECM synthesis were dependent on load frequency, as well as culture media pH.

The experimental results of this thesis suggest that the physical stretching of chondrocytes may have had more of an impact on stimulating proliferation and ECM synthesis than induced interstitial fluid flow.  Chondrocytes also require a period of preconditioning before the stimulated effects occur, but too high of a loading frequency can cause possible desensitization and/or a catabolic response.  Overall, the experiments were successful in identifying the stimulatory potential of tensile strains.  However, further improvements must be made to the long-term effects on tissue mechanical properties before tension can be used as an effective stimulus to produce better quality in engineered cartilaginous tissues.

abstract: M.A.Sc.


title: A Numerical Evaluation of the Design of an Autothermal Reformer for the Onboard Production of Hydrogen From Iso-Octane

contributor:
Oosthuizen, Patrick H.
Mechanical and Materials Engineering

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subject:
Auxiliary Power Unit
Autothermal Reformer
Iso-Octane
Hydrogen

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-03-09 12:14:27.627

abstract:
A numerical study was carried out to improve the design of an autothermal reformer for the onboard production of hydrogen to be used in fuel-cell- powered auxiliary power units (APU) to provide heating and electricity in long haul trucks when they are at rest. The development of these auxiliary power units is based upon the use of power generated by solid oxide fuel cell (SOFC) system, instead of from a conventional gasoline engine. The present work was undertaken to improve the design of a prototype autothermal fuel reformer that had been developed by the Fuel Cell Research Centre (FCRC) at Queen’s University to convert liquid hydrocarbon truck fuel to a hydrogen rich product gas. In this development work and in the previous work iso-octane (C8H18) has been used as a surrogate fuel.
Using this surrogate of gasoline, the reformer was simulated using various inlet steam/carbon (H2O/C), oxygen/carbon (O/C) molar ratios and gas-hourly-space-velocity (GHSV). In the reformer considered the reforming process is carried out in a compact tubular reactor with a centerline thermocouple tube using a 2% Pt-ZrCe based catalyst with a local porosity of 0.6. During the initial simulations, it was observed that near the start of the catalyst region there were large temperature gradients due to an exothermic partial oxidation reaction. In order to reduce the temperature gradients and facilitate heat transfer by conduction along the reformer, the central thermocouple tube was replaced with a central solid rod. The effects of variations in the thermal conductivity of central solid rod, of the reactor wall, of the catalyst bed, of the inert porous material near the inlet and the outlet of the catalyst bed, of the gas hourly space velocity, of the effectiveness factor of the chemical reaction mechanism on the performance of the reactor were studied. The results so obtained were analyzed to determine potential design improvements that would increase the hydrogen output. The results were compared with the previous numerical and experimental results obtained in the previous studies of the reformer and found to be in good agreement with the general trends of the temperature profiles as well as the outlet molar concentrations of product species.
After the analysis and evaluation of all the results, it was found that by replacement of central thermocouple tube with central solid rod made of high conductivity material and by using material for inert porous region at the outlet that had a thermal conductivity equal to that of the catalyst bed led to more even temperature profiles within the catalyst region. It was also found that the hydrogen molar percentage output could be increased by approximately more than 25% and that the length of the reactor could be reduced by 20mm by incorporating these changes in the reformer design.

abstract: M.A.Sc.


title: Mapping the Nation

contributor:
Ware, Tracy
English

subject:
Exploration Writing
English-Canadian Literature

abstract: Thesis (Ph.D, English) -- Queen's University, 2009-03-10 13:39:01.062

abstract: Focusing on the texts of James Cook, Samuel Hearne, Alexander Mackenzie, Archibald Menzies, David Thompson, and George Vancouver, Mapping the Nation:  Exploration and the English-Canadian Literary Imagination argues that exploration writing is a subgenre of travel writing defined by its empirical perspective and function.  Incorporated into the English-Canadian literary canon while being disparaged for its lack of literary qualities, exploration writing is used by English-Canadian literary histories, encyclopaedias, and companions to prove an environmentally deterministic developmental thesis of the national literature.  The developmental thesis permeates anthologies that offer excerpts of exploration writing and discussions that pertain to the influence of exploration writing on later English-Canadian literature that returns to it.  Returning to exploration writing addressing land exploration are Farley Mowat’s People of the Deer (1952), John Newlove’s “The Pride” (1965) and “Samuel Hearne in Wintertime” (1966), Don Gutteridge’s The Quest for North:  Coppermine (1973), Marion R. Smith’s Koo-Koo-Sint:  David Thompson in Western Canada (1976), and Brian Fawcett’s “The Secret Journal of Alexander Mackenzie” (1985).  Returning to exploration writing addressing oceanic exploration are Earle Birney’s “Pacific Door” (1947), Damnation of Vancouver (1952), and “Captain Cook” (1961); P. K. Page’s “Cook’s Mountains” (1967); George Bowering’s George, Vancouver:  A Discovery Poem (1970); Gutteridge’s Borderlands (1975), and George Bowering’s Burning Water (1980), Audrey Thomas’s “The Man with the Clam Eyes” (1982) and Intertidal Life (1984).  Each text represents an individual interpretation of exploration writing that operates through genre and forms of return such as allusion, imitation, paraphrase, and quotation.

abstract: PhD


title: Mechanisms of Heme-Oxygenase-1 Cytoprotection for Gene and Cell Based Therapies against Cardiovascular Disease

contributor:
Funk, Colin D.
Physiology

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subject:
Heme-Oxyeganse-1
Cardiovascular Disease
Protein Kinase B
Atherosclerosis
Endothelial Progenitor Cells
Plaque Stability

abstract: Thesis (Ph.D, Physiology) -- Queen's University, 2009-04-21 15:31:14.05

abstract:
Establishing the cellular and molecular basis for cardiovascular disease and the application of tools to manipulate the cardiovascular system genetically provide potential for new forms of treatment against cardiovascular disease, including: atherosclerosis, myocardial ischemia, cardiac hypertrophy and heart failure.  Heme oxygenase-1 (HO-1) is an enzyme that has potential for the treatment of cardiovascular diseases (CVD).
Atherosclerotic plaques express high levels of HO-1.  Advanced plaques are stabilized in part through the separation of plaque constituents from the blood by the fibrous cap made up of smooth muscle cells.  Protection of smooth muscle cells from apoptosis in the fibrous cap may be a means of promoting plaque stability in patients.  Here we show that expression of HO-1 in human vascular smooth muscle cells renders them resistant to apoptosis mediated by oxidative stress.  The cytoprotective mechanism mediated by HO-1 is mediated in part through protein kinase B (Akt).
Plaque rupture may lead to myocardial infarction.  Tissue recovery after mycocardial infarction requires neovascularization for improved tissue perfusion.  A novel cell type recently discovered in the circulation has been characterized as an endothelial progenitor cell (EPC) and appears capable of promoting neovascularization of post-infarct tissue, thereby enhancing tissue recovery and perfusion.  Most EPCs transplanted into the infarct environment do not survive or are not retained to function in neovascularization.  Here we show that expression of HO-1 and its cytoprotective partner Akt protect EPCs in an infarct environment and promote EPC function in an infarct environment.
Oxidative stress can result in maladaptive cardiomyocyte hypertrophy.  In a model of oxidative stress-induced myocyte hyperterophy we demonstrate the expression of HO-1 prevents cellular hypertrophy through antioxidant mechanisms and regulation of the transcription nuclear factor kappa B (NF-κB).
Atherosclerotic plaque vulnerability is determined by the composition of the lesion.  We demonstrate that HO-1 deficient mice have more calcified and fibrotic lesions.  This may have implications in the management of late stage atherosclerosis.
Collectively, this work demonstrates new insights into the molecular mechanisms of cardiovascular cells under stress that may have implications for strategies aimed at treating CVD using HO-1.

abstract: PhD


title: The distribution and controls on silver mineralization in the Main Zone of the 2.68 Ga Archean Hackett River Zn-Pb-Cu-Ag volcanogenic massive sulfide (VMS) deposit, Nunavut, Canada

contributor: Geological Sciences and Geological Engineering

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subject:
Silver
VMS
Archean
Slave Craton
Canada
Freibergite

abstract: Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-03-12 10:46:49.993

abstract: The 2.68 Ga Zn-Pb-Cu-Ag Hackett River Main Zone (HRMZ) volcanogenic massive sulfide (VMS) deposit, within the Hackett River Greenstone Belt of the Archean Slave Craton is highly enriched in Ag (and Pb) compared to other VMS deposits of a similar age and type. The mineralization has been sub-divided into five categories based on mineralogy, textures and stratigraphic location: 1) disseminated footwall sulfides, 2) copper-rich stringer sulfides, 3) pyrite-poor sphalerite-pyrrhotite-chalcopyrite mineralization located at the top of the stringer zone, 4) mineralization in calc-silicate altered units and 5) sphalerite-pyrite massive sulfide mineralization. Using a mass-balance for Ag calculated from electron microprobe analyses, pyrrhotite and chalcopyrite in type 1 mineralization contain negligible Ag and in type 2, Bi-Ag-(Pb) sulfides, Ag-Bi-Se enriched galena and chalcopyrite are the dominant Ag hosts. Within type 3, freibergite and galena are the main silver hosts. In type 4, Ag is hosted in disseminated electrum and freibergite while freibergite in type 5 hosts 99% of the Ag. Overall, Ag-rich freibergite contains 79.4% of the total Ag, chalcopyrite hosts 6.3% and galena contains 1.8% of the Ag. Trace minerals such as electrum, stephanite, acanthite and Bi-bearing sulfides host the remainder of the Ag (12.5%) and have a restricted spatial distribution. Mineral assemblages have undergone pervasive recrystallization and annealing during amphibolite grade metamorphism with localized redistribution of base and precious metals from metamorphism at a grain scale only. Within freibergite and chalcopyrite, Ag directly substitutes for Cu within the mineral lattice and replaces Pb in galena by coupled substitution with Bi and to a lesser extent, Sb. The principal controls on Ag residence in the HRMZ are temperature and redox conditions (which varies with distance to the hydrothermal vent) and the ratio of Bi and Sb available for coupled substitution with silver within galena. Subsequent deposit-scale zone refining is the principal factor influencing the distribution of Ag. Lower temperatures and more oxidizing conditions favour partitioning of Ag into freibergite and less oxidizing conditions favour galena. At higher temperatures, the most reducing conditions favour incorporation of Ag in Ag-Bi rich galena (plus Se) and Bi-bearing sulfides or Ag-rich chalcopyrite under lesser reducing conditions.

abstract: M.A.Sc.


title: Maternal Cardiac Autonomic Function and Fetal Behaviour in Hypertensive and Obese Pregnancies

contributor:
Brown, C. Ann
Kisilevsky, Barbara
Nursing

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subject:
Hypertension
Pregnancy
Obesity
Fetal Behaviour
Heart Rate Variability

abstract: Thesis (Master, Nursing) -- Queen's University, 2009-03-13 17:45:41.837

abstract:
Hypertension in pregnancy is associated with autonomic dysregulation whereas the effects of obesity in pregnancy on maternal cardiac autonomic function are poorly understood. Furthermore, hypertension in pregnancy is associated with placental insufficiency and fetal growth restriction, whereas obesity in pregnancy is associated with placental inflammation and macrosomia. Fetal growth restriction is associated with an increased risk for language deficits at 2-5 years of age. However, maternal cardiac autonomic function and fetal auditory processing in pregnancies complicated by hypertension compared to obesity have not been examined and are the focus of this study. Maternal short-term cardiac autonomic modulation in the supine and standing postures as well as spontaneous and auditory elicited fetal behaviours were compared in 61 mother-fetal pairs (n=20 hypertensive; n=20 overweight; n=21 normal weight comparison pregnancies) from 34 to 40 weeks gestation. Maternal cardiovascular measures included systolic arterial finger-cuff blood pressure and electrocardiographic recordings of heart rate. Spontaneous observations of fetal heart rate, body and breathing movements, muscle tone and an estimate of amniotic fluid were made. Finally, each fetus received a 2 min recording of their mother and the mother’s voice in reverse (counterbalanced over subjects).
When standing (othostatic stress), all three groups of women exhibited a decrease in the average baroreflex slope, parasympathetic nervous system indicator and high frequency power compared to the supine position. In a 20 min observation of spontaneous behaviour in the maternal supine compared to the standing position, fetuses of hypertensive mothers had, on average, fewer heart rate accelerations ≥ 15 bpm while the mother was supine; fetuses in the normal weight comparison group experienced more accelerations while the mother was supine. The average number of heart rate accelerations did not change in the two maternal positions for fetuses in the obese group.  Fetuses in the three groups showed differential responses to the mother’s voice played forward and backward. It was concluded that there were no differences in maternal heart rate variability measures in the group of mildly hypertensive women compared to those with obesity and the normal weight comparison group. Differential spontaneous fetal heart rate accelerations and responses to the mother’s voice among the three groups needs further study with sufficient sample size to examine behaviour as a function of gestational age.

abstract: MNSc.


title: Dunsmuir and the Changing Faces of Curial Deference & Tribunal Expertise: The Shaping of a Unitary Standard of Judicial Review In Administrative Law.

contributor:
Corbett, Stanley
Law

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subject:
judicial review
tribunal expertise
standard of review
Dunsmuir
Administrative Law
curial deference
Dyzenhaus
reasonableness
Southam
Bibeault
Bastarache
Iacobucci
Nipawin

abstract: Thesis (Master, Law) -- Queen's University, 2009-03-17 14:58:15.299

abstract: This paper focuses on the evolution of “reasonableness” as a unitary standard of judicial review and the role of tribunal expertise in that process. The modern era begins with Nipawin in 1973, a time when judicial review operated with a crude binary system of standards that allowed for either full curial deference (patent unreasonableness) or no deference (correctness). It ends in 2008 with Dunsmuir and the jettisoning of the highest standard of curial deference, the standard of patent unreasonableness.  Correctness is now implicitly understood not as a standard but, as the justified absence of the need to extend deference to a tribunal`s decision. Patent unreasonableness and the middle ground standard of reasonableness have ostensibly been "collapsed" into a single more rational, workable, flexible and sophisticated unitary system based on the multi faceted standard of reasonableness.  It is argued that the new “standard of review analysis” expressed in Dunsmuir is simply a comprehensive restatement of all the previously articulated diverse and, typically, non-dispositive factors and exceptions. The hallmarks of this new standard are the recognition that, more often than not in administrative law, there is no one right or best answer and that, a reviewing court will respect and affirm a tribunal’s choice if it is within the range of options provided it is well reasoned. This paper also addresses the primarily academic criticism of the Supreme Court over conceptual problems in distinguishing patent unreasonableness from reasonableness, a dispute fuelled by this court’s continued attempts to justify a standard of review that allowed for a tribunal’s right to be wrong. It is argued that patent unreasonableness had become less of a standard of review and more of a simple expression of judicial censure for egregious fault in decision making; a qualifier to a finding of unreasonableness. Arguably that role may have been preserved even with the collapsing of the two standards into one standard in Dunsmuir. While Dunsmuir should have clarified many of the issues the three-way difference of opinion in the Court demonstrates continuing deep rifts that may portend further uncertainty. Uptake by lower courts indicates otherwise.

abstract: LL.M.


title: The role of dopamine-related genes in autism spectrum disorders:  Evidence for specific genes and risk for ASD in families with affected males

contributor:
Holden, Jeanette J. A.
Physiology

format:
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subject:
autism spectrum disorders
dopamine pathway
gene
association study

abstract: Thesis (Ph.D, Physiology) -- Queen's University, 2009-03-18 13:58:12.223

abstract: Individuals with autism spectrum disorders (ASDs) are impaired in cognitive processes and emotional regulation, and exhibit stereotyped behaviours.  Dopamine (DA) modulates executive functions, learning, memory, emotional processing and social cognition; all of which are impaired in individuals with ASDs.  Because DA modulates a number of processes that are impaired in individuals with ASDs, genes in the dopaminergic pathway are good candidates for genes influencing autistic behaviours.  As our previous findings suggested a role for a dopamine-related gene in families with only affected males, this thesis describes a comprehensive study of five genes affecting DA synthesis, levels and function in mothers and affected males with ASDs in an initial TEST cohort of 112 male-only affected sib-pair families as well as a replication study in three additional male-only family cohorts.  I genotyped three to five polymorphisms in the TH, SLC6A3, DRD1, DRD2 and PPP1R1B genes and performed population-based single marker case-control comparisons, family-based association tests, quantitative transmission disequilibrium tests as well as haplotype-based analyses and tests for gene-gene interactions.  I found evidence for association of the DRD1 (P=0.0027-0.040), DRD2 (P=0.0002-0.007) and PPP1R1B (P=0.00042-0.001) genes with autism in affected males from the TEST cohort.  Evidence for DA-related gene interactions were found between polymorphisms in DRD1, DRD2 and PPP1R1B (P=0.0094-0.012) in affected males relative to a comparison group.  Furthermore, I found that polymorphisms in the TH and DRD1 genes were associated with the risk for mothers having sons with ASD in the TEST families (P=0.007-0.025) and putative risk alleles in DRD1 and DRD2 were preferentially transmitted from mothers (P=0.016) and fathers (P=0.023) respectively, to affected children.  All findings remained significant following corrections for multiple testing.  The TEST cohort findings were not replicated in other family cohorts.  However, an examination of dysmorphology data for the different family sets revealed phenotypic differences and thus, genetic differences are to be expected.  In summary, I found evidence for a contribution of DA-related genes in a specific family cohort with ASDs.  Additional functional and phenotypic studies will enable a better understanding of the contributions and implications of these findings to our understanding of autism.

abstract: PhD


title: Laboratory study evaluating electrical resistance heating of pooled trichloroethylene

contributor:
Kueper, Bernard H.
Civil Engineering

format:
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subject:
TCE
Remediation
ERH
DNAPL
Electrical Resistance Heating
Thermal
Pooled

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2009-03-18 14:40:46.019

abstract:
A laboratory scale study was conducted to evaluate the thermal remediation of trichloroethylene (TCE) in a saturated groundwater system using electrical resistance heating (ERH). Two experiments were conducted using a two-dimensional polycarbonate test cell, the first consisting of a single pool of TCE perched above a capillary barrier, the second consisting of two pools of TCE each perched on separate capillary barriers.  Temperature data was collected during the heating process from an array of 32 thermocouples located throughout the test cell. Visualization of the vaporization of liquid phase TCE, as well as the upward migration of the produced vapour was recorded using a digital camera.  Chemical testing was performed 48 hours after experiment termination to measure post heating soil concentrations.  A co-boiling plateau in temperature was found to be a clear and evident earmark of an ongoing phase change in the pooled TCE.  Temperature was found to increase more rapidly in the second experiment that included a fully spanning barrier. As temperatures increased above the co-boiling plateau, vapour rise originating from the source zone was observed, and was found to create a high saturation gas zone beneath the upper capillary barrier when no clear pathway was available for it to escape upwards.  When the source zones had reached the target temperature of 100°C and the ERH process stopped, this high saturation gas zone condensed, leading to elevated TCE concentrations below as well as within the capillary barrier itself. The water table within the experimental cell was also noted to drop measurably when the gas zone collapsed. Post-testing chemical analysis showed reductions in TCE concentrations of over 99.04% compared to the source zone, although due to condensation of entrapped gas and convective mixing, there was a net redistribution of TCE within the experimental domain, especially within confined areas below the capillary barriers.

A secondary set of experiments were conducted using a homogenous silica sand pack with no chemical contaminants to determine the effect, if any, of the wave shape of electrical input on the ERH process.   It was found that in early time heating, square wave inputs consistently produced a more localized heating pattern when compared to the standard sine wave electrical input.  This effect equalized between the two experiments as the ERH process went on, perhaps due to the increased dominance of conduction and convection as the mode of heat transfer in the test cell at higher temperatures.  It is believed that the localization of heating in square wave experiments is due to a consistent power supply due to the lack of a sinusoidal ramping in power delivery.

abstract: M.Sc.


title: Proteomic Analysis of the Heat Shock Response in the Nervous System of Locusta migratoria

contributor:
Shoemaker, Kelly
Robertson, Mel
Biology

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subject:
Heat Shock Response
Locusta Migratoria
Nervous System
Proteomic
Immunohistochemistry
Phase Polymorphism

abstract: Thesis (Master, Biology) -- Queen's University, 2009-03-20 12:28:32.962

abstract: There is a thermal range for the operation of neural circuits beyond which nervous system function is compromised. Poikilotherms are particularly vulnerable to thermal stress, since their body temperature can fluctuate with ambient temperature. Animals that experience frequent hyperthermia have various coping mechanisms such as the thermoprotective effect of a prior exposure to sublethal temperatures (heat shock response). The molecular mechanisms of this thermoprotection have yet to be understood. This project studies the changes in protein expression in the nervous system of gregarious Locusta migratoria subjected to heat shock. For this purpose, proteins were extracted from metathoracic ganglia (MTG) by different methods and a proteomic map was subsequently obtained by 2-D gel electrophoresis which was compared between control (CON) and heat-shocked (HS) animals. Additionally, the localization pattern of Hsp70 was studied in the MTG of CON and HS gregarious locusts. Although 2-D gels showed changes in the amount of different isoforms of ATP-synthase β, the overall amount of this protein subunit was found to be unchanged. My experiments also revealed no significant change in the distribution of Hsp70 in the MTG of locusts caused by HS. However, new findings show that this protein is constitutively expressed at higher levels in perineurium, glia and tracheal cells than in neurons. In separate experiments, isolated locusts were also examined in order to measure any stress-associated increase of Hsp70 in the tissues of animals not previously exposed to crowding pressure. Quantitative western blots did not show a consistent change of the Hsp70 level in the MTG of isolated locusts following heat shock. Results of my research suggest that the change in the protein profile of the metathoracic ganglion following heat shock, if it exists, is subtle or occurs in very low-abundance proteins whose monitoring requires the application of special techniques. Alternatively, the thermoprotective effect of heat shock on the nervous system might be promoted through other pathways which can change the protein activity at the post-translational level and may work independently from protein synthesis.

abstract: M.Sc.


title: Cellular Automata: Algorithms and Applications

contributor:
Salomaa, Kai Jr
Computing

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subject:
Cellular automata
Encryption
Public key
Convex hull
Wireless sensor network
Traffic

abstract: Thesis (Master, Computing) -- Queen's University, 2009-03-23 11:20:58.666

abstract: Cellular automata (CA) are an interesting computation medium to study because of their simplicity and inherently parallel operation. These characteristics make them a useful and efficient computation tool for applications such as cryptography and physical systems modelling, particularly when implemented on specialized parallel hardware. In this dissertation, we study a number of applications of CA and develop new theoretical results used for them. We begin by presenting conditions which guarantee that a composition of marker cellular automata has the same neighbourhood as each of the individual components. We show that, under certain technical assumptions, a marker cellular automaton has a unique inverse with a given neighbourhood. We use these results to develop a working key generation algorithm for a public-key cryptosystem based on reversible cellular automata originally conceived by Kari. We also give an improvement to a CA algorithm which solves a version of the convex hull problem, ensuring that the algorithm does not require a global rule change and correcting the operation in a special case. Finally, we study a modified version of an established CA-based car traffic flow model for the single-lane highway case, and use CA as a modelling tool to investigate the coverage problem in wireless sensor network design. We developed functional software implementations for all of these experiments.

abstract: M.Sc.


title: Subharmonic Mixers in CMOS Microwave Integrated Circuits

contributor:
Saavedra, Carlos E.
Electrical and Computer Engineering

format:
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subject: Electrical Engineering

subject: Monolithic Microwave Integrated Circuits

subject: RF CMOS Integrated Circuits

subject: Subharmonic Mixers

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-03-24 16:08:31.805

abstract:
This thesis explores the design and applications of subharmonic mixers in CMOS microwave integrated circuits.  First, a 2x down-converting subharmonic mixer is demonstrated with a measured conversion gain of 8 dB using a 2.1 GHz RF signal. Extending the concept of the 2x subharmonic mixer, a 4x subharmonic mixer is proposed that operates in the 12 GHz Ku-band.  This circuit is the first 4x subharmonic mixer in CMOS, and achieves a 6 dB conversion gain, which is the highest for any 4x subharmonic mixer regardless of circuit topology or fabrication technology. Furthermore, it achieves very high measured isolation between its ports (e.g. 4LO-RF: 59 dB).

Since both the 2x and the 4x subharmonic mixers require a quadrature oscillator, a new oscillator circuit is presented that could be used with either of the aforementioned mixers. This quadrature oscillator uses active superharmonic coupling to establish the quadrature fundamental relationship. The oscillation frequency is 3.0 GHz and the measured output power is -6 dBm.

A dual-band mixer/oscillator is also demonstrated that can operate as either a fundamental mixer or a subharmonic mixer depending on a control voltage. This circuit operates from 5.0 GHz to 6.0 GHz or from 9.8 GHz to 11.8 GHz by using either the fundamental output or the second harmonic output of the quadrature oscillator circuit described above and achieves conversion gain over both frequency bands.

A novel frequency tripler circuit is presented based on a subharmonic mixer. This circuit uses the 2x subharmonic mixer discussed above, along with a feedforward fundamental cancellation circuit. The measured fundamental suppression is up to 30 dB and the conversion gain is up to 3 dB. Finally, a frequency divider circuit based on a subharmonic mixer is presented that divides the input signal frequency by a factor of three. This circuit uses a single-balanced version of the 2x subharmonic mixer described above in a regenerative divider topology. The measured input signal bandwidth is 300 MHz (5.2 GHz to 5.5 GHz) with an input power of -7 dBm and the maximum conversion gain is 0 dB.

abstract: PhD


title: The Effect of Fragmentation Specification on Blasting Cost

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

format:
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subject: Blasting Burden Cost Diameter Fragmentation

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2009-03-27 07:34:33.787

abstract:
Drilling and blasting are seen as sub-systems of size reducing operations in mining. To have better design parameters for economical excavation of mineral production and fragmentation, the comminution and fragmentation operations need to be studied and optimized independently, as well as together, to create optimized use of energy and cost-effective operation.
When there is a change in drillhole diameter or fragmentation specification, changes in the blast design parameters are required affecting the cost of a drilling and blasting operation. A model was developed to calculate blast design parameters and costs on the basis of the required 80% fragment size needed for crusher operation. The model is based on previously developed fragmentation models, found in the literature. The model examines the effect of drilling diameter on blasting requirements to achieve certain fragmentation targets and calculates blast design parameters and costs for a range of diameters from 75 to 350 mm.
 To examine the effectiveness of this model, two different 80% passing sizes of fragments have been considered. It was shown that cost optimization occurs at an intermediate diameter, since there are opposing trends of the effect of diameter on powder factor and accessories needed. To achieve a certain fragmentation target, the total cost of drilling and blasting shows a clear trend allowing an optimum selection of diameter. The selected diameter also allows the examination of the suitability of the drill machine under the given geological and operational conditions of the drilling site.

abstract: M.A.Sc.


title: The Characteristics of Ways of Learning in the Pharmaceutical Sales Industry

contributor:
Colgan, Lynda
Education

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subject:
Workplace Learning
Self-Directed Learning
Pharmaceutical
Distributed Workforce

abstract: Thesis (Master, Education) -- Queen's University, 2009-04-23 16:16:11.431

abstract:
Employee learning provides significant competitive advantage for organizations. Understanding how employees learn in different work contexts can support continuing, effective, and frequent learning. Although most workplace learning is done informally, the characteristics of that learning are minimally reported and the criteria used to define learning as informal are inconsistent.
Research into continuing professional development in knowledge-intense environments or distributed workforces is sparse. The pharmaceutical sales industry is a previously unexamined knowledge-intense environment with a geographically distributed workforce.
This qualitative case study sought a better understanding of how pharmaceutical sales representatives learn for work by documenting and describing those ways of learning reported as most effective and most frequent. Twenty sales agents from 11 organizations participated in a Delphi collaboration to create a comprehensive list of 64 ways they learn for work. In-depth individual interviews with five agents provided deep detail about learning in this industry, including the ways of learning that the participating agents perceive to be most effective and most frequent. The Colley, Hodkinson and Malcom (2003) framework was interpreted, applied, and extended in order to identify attributes of formality and informality and other characteristics inherent in the ways of learning reported as most effective and most frequent.
This study showed that agents learn in a wide variety of ways and that most of those ways are self-initiated, self-directed, minimally structured, and often involve intentional incidental learning: agents are constantly alert to capture learning while engaged in work activities. Learning during customer interactions on the job was reported as particularly effective and frequent. Other reported effective ways of learning varied with the agent but usually involved self-directed learning with mixed formal and informal attributes. It was determined that learning plays a special role in this industry: much of what is learned for work is not being applied directly to the job of sales promotion.  Instead, agents use learning to develop themselves as resources for physicians in order to gain the customer-access required to promote their products.  In this way, learning on the job is the job.

abstract: M.Ed.


title: Preferential Potentiation of Weaker Inputs to Primary Visual Cortex by Activation of the Basal Forebrain in Urethane Anesthetized Rats

contributor:
Dringenberg, Hans C.
Neuroscience Studies

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subject: Acetylcholine Neuromodulation

abstract: Thesis (Master, Neuroscience Studies) -- Queen's University, 2009-03-31 08:49:23.896

abstract:
The ability of the brain to store information and adapt to changes in the sensory environment stems from the capability of neurons to change their communication with
other neurons (“synaptic plasticity”). However, the ability of synapses to change (e.g., strengthen) is profoundly influenced by various chemical signals released in the nervous system (neuromodulators). Such modulatory effects may be preferential for different types of synapses. For example, cortical acetylcholine (ACh) has been shown to result in a relative enhancement of thalamocortical over intracortical synapses. Here, I tested the hypothesis that field postsynaptic potentials (fPSPs) in the rat primary visual cortex (V1) evoked by single pulse stimulation of the lateral geniculate nucleus (LGN) can be potentiated when LGN stimulation is paired with short bursts of stimuli applied to the basal forebrain (BF), the major source of ACh released in the cortex. Stimulation of the ipsi- and contralateral LGN elicited fPSPs in V1, with fPSPs triggered from the contralateral LGN exhibiting longer latencies and smaller amplitudes relative to fPSPs in ipsilateral projections. Stimulation bursts applied to the BF, paired with single, delayed LGN pulses, resulted in an enhancement of fPSP amplitude (~25%) for contralateral inputs at short (130 ms), but not longer (200-1000 ms) pairing intervals, while ipsilateral fPSPs failed to show significant potentiation over these intervals. The enhancement of the
contralateral LGN-V1 fiber system induced by BF pairings was abolished by systemic or V1 application of the muscarinic receptor antagonist scopolamine, while systemic
nicotinic receptor blockade was ineffective. These data suggest that there is a differential capacity for plasticity induction between strong, ipsilateral and weaker, contralateral fiber inputs to V1, with weaker inputs exhibiting greater synaptic enhancement following pairing with BF stimulation to elicit cortical ACh release. This preferential readiness for
synaptic potentiation in normally weaker, non-dominant fiber inputs to V1 may facilitate the detection and integration of separate sensory signals originating in thalamic sensory nuclei.

abstract: M.Sc.


title: Simulation of Engineered Nanostructured Thin Films

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subject: Monte Carlo

subject: Kinetic Monte Carlo

subject: Nanostructured Thin Films

subject: Finite-Difference Time-Domain

subject: Surface growth model

subject: Simulation

subject: Glancing angle deposition

subject: Atomic deposition

subject: Surface diffusion

subject: Vapour deposition

subject: Crystal microstructure

subject: Scanning electron microscopy

subject: Density

subject: Roughness

subject: Fractal dimension

subject: Nanotechnology

subject: Computational electromagnetics

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-03-31 13:22:11.843

abstract: The invention of the Glancing Angle Deposition (GLAD) technique a decade ago enabled the fabrication of nanostructured thin films with highly tailorable structural, electrical, optical, and magnetic properties. Here a three-dimensional atomic-scale growth simulator has been developed to model the growth of thin film materials fabricated with the GLAD technique, utilizing the Monte Carlo (MC) and Kinetic Monte Carlo (KMC) methods; the simulator is capable of predicting film structure under a wide range of deposition conditions with a high degree of accuracy as compared to experiment. The stochastic evaporation and transport of atoms from the vapor source to the substrate is modeled as random ballistic deposition, incorporating the dynamic variation in substrate orientation that is central to the GLAD technique, and surface adatom diffusion is modeled as either an activated random walk (MC), or as energy dependent complete system transitions with rates calculated based on site-specific bond counting (KMC). The Sculptured Nanostructured Film Simulator (SNS) provides a three-dimensional physical prediction of film structure given a set of deposition conditions, enabling the calculation of film properties including porosity, roughness, and fractal dimension. Simulations were performed under various growth conditions in order to gain an understanding of the effects of incident angle, substrate rotation, tilt angle, and temperature on the resulting morphology of the thin film. Analysis of the evolution of film porosity during growth suggests a complex growth dynamic with significant variations with changes in tilt or substrate motion, in good agreement with x-ray reflectivity measurements. Future development will merge the physical structure growth simulator, SNS, with Finite-Difference Time-Domain (FDTD) electromagnetics simulation to allow predictive design of nanostructured optical materials.

abstract: M.Sc.


title: The Effects of Thermal Habitat and Macroinvertebrate Predation on the Crustacean Zooplankton Community of a Small Boreal Shield Lake

contributor:
Arnott, Shelley E.
Keller, Wendel (Bill)
Biology

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subject:
Climate
Lake
Crustacean Zooplankton
Freshwater
Predator-Prey
Chaoborus
Notonectids
Macroinvertebrates
Stratification

abstract: Thesis (Master, Biology) -- Queen's University, 2009-03-31 13:29:35.975

abstract:
Climate change will affect all freshwater ecosystems via both direct physiological and indirect, biologically-mediated effects. Small lakes (< 10 ha) numerically dominate the Boreal Shield and represent an important habitat for aquatic biota. Small, shallow lakes are particularly responsive to climate-induced changes in thermal structure. Furthermore, biological interactions may be particularly important in small lakes where space, habitat heterogeneity, and thermal refugia are limited. Therefore, it is critical to understand and predict the consequences of climate change for community dynamics in small Boreal Shield lakes.
Using 10 years of monitoring data and a field experiment I tested for differences in crustacean zooplankton community structure between warm and cool lake habitats. I classified years from a small, shallow Boreal Shield lake as ‘warm’ or ‘cool’ based on several characteristics of lake thermal structure. Since macroinvertebrates are often the main predators in small, shallow lakes, I further tested for potential interactions between lake thermal structure and spatially-dependent macroinvertebrate predation using in situ mesocosms.
Body sizes of two ubiquitous crustacean zooplankton taxa, Leptodiaptomus minutus and Bosmina spp., were reduced in warm years, but no differences in abundance or diversity were detected at the annual scale. In contrast, in 15d enclosure experiments, crustacean zooplankton abundance and calanoid copepodid body size were reduced by the vertically-migrating predator Chaoborus punctipennis, but only in warm isothermal conditions. Zooplankton lowered their daytime depth distribution to avoid the surface-orienting notonectid predator, Buenoa macrotibialis, regardless of thermal habitat. No predation effect was detected in a hot (25ºC) isothermal habitat where both Chaoborus and notonectids were likely heat-stressed.
Differences in abundance effects between the enclosure and monitoring data are likely due to the scales at which the analyses were conducted. Over short timescales predator-prey dynamics depended on lake thermal structure. However, over annual timescales zooplankton response was averaged across periods of seasonal change in thermal structure and biological processes, which may dampen the short-term effects associated with strong predation in isothermal conditions.  Therefore, the importance of macroinvertebrate predators in regulating crustacean zooplankton community structure may increase if small lakes become progressively more isothermal with future climate change.

abstract: M.Sc.


title: Modulation of Cardiac Myocyte Function by Reactive Oxygen Species

contributor:
Ward, Christopher Andrew
Physiology

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subject:
H2O2
Hydrogen Peroxide
Reactive Oxygen Species
Cardiac Myocytes
Arrhythmia
Afterdepolarizations

abstract: Thesis (Master, Physiology) -- Queen's University, 2009-03-31 14:00:34.21

abstract: Previous investigations have demonstrated that reactive oxygen species such as hydrogen peroxide (H2O2) have the ability to alter electrophysiological and mechanical properties of rat ventricular cardiac myocytes. However, despite the breadth of the literature, there is little definitive consensus on the cellular mechanisms. The purpose of this study, therefore, was to study the cellular mechanism of action of H2O2 and test whether H2O2-mediated affects were partially a result of reverse-mode Na+/Ca2+ exchanger (NCX) activity. Unloaded cell shortening, intracellular Ca2+ transients, caffeine-induced Ca2+ transients, L-type Ca2+ channel recordings, and action potential waveforms were recorded in the presence of combinations of different compounds including Cd2+, H2O2, and KB-R7943. H2O2 was found to cause significant positive inotropy by an increase in contractility of 80 ± 20 % (n=6) and an increased amplitude of Ca2+ transients by 24 ± 14 % (n=8), relative to pre-treatment values. Interestingly, H2O2 caused an increase in contractility even in the presence of Cd2+ block from 4 ± 1 % (n=9) to 15 ± 3 % (n=5) of resting cell length. Using caffeine pulse experiments to induce unloading of the sarcoplasmic reticulum (SR), we found that 100µM H2O2 did not significantly alter SR Ca2+ load. Under control conditions, H2O2 significantly increased L-type Ca2+ currents while this H2O2-induced increase was not observed in myocytes pretreated with Cd2+. Positive inotropy in the presence of H2O2 was blocked using 10µM KB-R7943, a selective reverse-mode inhibitor of the NCX. However, it was found that 10µM KB-R7943 alone altered action potential profile and suppressed normal contraction. Altogether, the major finding of this study is that H2O2 has the ability to enhance myocardial contractility, even under conditions of L-type Ca2+ channel inhibition, through a mechanism that likely involves reverse-mode of the NCX.

abstract: M.Sc.


title: A Framework for Efficient Bandwith Management in Broadband Wireless Access Systems

contributor:
Hassanein, Hossam S.
Nasser, Nidal
Computing

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subject:
Broadband Wireless Access Systems
Bandwidth Management

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2009-04-01 15:35:36.213

abstract:
Broadband Wireless Access Systems (BWASs) such as High Speed Downlink Packet
Access (HSDPA) and the Worldwide Interoperability for Microwave Access (WiMAX), pose a myriad of new opportunities for leveraging the support of a wide range of “content-rich” mobile multimedia services with diverse Quality of Service (QoS) requirements. This is due to the remarkably high bandwidth that is supported by these systems, which was previously only available to wireline connections. Despite the support for such high bandwidth, satisfying the diverse QoS of users while maximizing the revenues of network operators is still one of the major issues in these systems. Bandwidth management, therefore, will play a decisive role in the success of such wireless access systems. Without
efficient bandwidth management, network operators may not be able to meet the growing demand of users for multimedia services, and may consequently suffer great revenue loss.  Bandwidth management in BWASs is, however, a challenging problem due to many issues that need to be taken into consideration. Examples of such issues include the diverse QoS requirements of the services that BWASs support, the varying channel quality conditions of mobile users, and hence the varying amount of resources that are needed to guarantee certain QoS levels during the lifetime of user connections, the utilization of shared channels for data delivery instead of dedicated ones and network congestion.

In this thesis, we address the problem of bandwidth management in BWASs and
propose efficient economic-based solutions in order to deal with these issues at different bandwidth management levels, and hence enhance the QoS support in these systems. Specifically, we propose a bandwidth management framework for BWASs. The framework is designed to support multiple classes of traffic with different users having different QoS requirements, maximize the throughput of BWASs, support inter- and intra-class fairness, prevent network congestion and maximize the network operator’s revenues. The framework consists of three related components, namely packet scheduling, bandwidth provisioning and Call Admission Control-based dynamic pricing. By
efficiently managing the wireless bandwidth prior to users’ admission (i.e.,pre-admission bandwidth management) and during the users’ connections (i.e., post-admission
bandwidth management), these schemes are shown to achieve the design goals of our
framework.

abstract: PhD


title: Genesis and Evolution of the Pierina High-Sulphidation Epithermal Au-Ag Deposit, Ancash, Peru

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subject:
Economic Geology
Geochemistry
Stable Isotopes
Epithermal Systems

abstract: Thesis (Ph.D, Geological Sciences & Geological Engineering) -- Queen's University, 2009-04-01 16:02:47.525

abstract:
The Pierina high-sulphidation epithermal Au-Ag deposit is located in the Cordillera Negra of north-central Perú, ~ 5km north of the coeval intermediate-sulphidation Ag–base metal Santo Toribio deposit, and in rocks of the Calipuy Supergroup. The deposit contains ~ 8 M oz Au, hosted in non-refractory iron oxides and, with heap-leach extraction, is one of the lowest-cost Au producers in the world.
	Stage Ia (15 Ma) and Ib (14.4 Ma) advanced-argillic alteration formed from mixed magmatic and meteoric waters. The main, 14.4 Ma event produced vuggy quartz alteration, focussed in a 16.9 Ma dacitic pumice-lithic tuff, and surrounded by quartz-alunite, quartz-dickite, and illite-montmorillonite alteration zones, the product of increased meteoric water contributions towards the periphery of the deposit.
	Stage II sulphide-barite mineralization introduced gold and silver, hosted submicroscopically in the disseminated high-sulphidation pyrite-enargite assemblage. Precipitation occurred from a low-to-medium - salinity magmatic fluid that mixed with meteoric waters at the site of ore deposition.
	A 14.1 Ma 40Ar/39Ar age for supergene alunite records the rapid incursion of meteoric waters into the deposit. The resulting oxidation of sulphides to schwertmannite, goethite, and hematite was facilitated by microbes, recorded by the stable-isotopic compositions of supergene barite+acanthite. Schwertmannite is enriched in Au and Ag and is the main precious-metal host.
Regional pedimentation is inferred to have initiated retrograde boiling of the source magma chamber at 15 Ma, with renewed magma incursion triggering major alteration at 14.4 Ma. Both events involved the exsolution of an SO2-rich vapour and a more saline aqueous fluid. The latter migrated to Santo Toribio generating phyllic alteration and intermediate-sulphidation mineralization, whereas the SO2-rich vapours caused pyrite-bearing feldspar-destructive alteration along fluid pathways during ascent to Pierina. The subsequent single-phase, H2S-rich mineralizing fluid exsolved from the retracting magma at higher pressures. Vapour contraction during ascent along altered, unreactive pathways minimized the loss of S- and H+, optimizing the transport of Au as AuHS0. Watertable displacement resulting from pediment incision promoted the flow of groundwater into the epithermal environment where mixing with magmatic fluids precipitated gold. Supergene oxidation optimized conditions for microbial activity, a critical factor in the generation of economic mineralization.

abstract: PhD


title: Ground displacements and pipe response during pulled-in-place pipe installation.

contributor:
Brachman, Richard W. I.
Moore, Ian D.
Civil Engineering

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subject:
Trenchless technology
Pipe bursting
Horiznontal directional drilling
High density polyethylene
Ground displacement
Pipe
Adjacent utility
Strain
Stress
Long-term performance

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-04-01 18:19:24.434

abstract:
Polymer pipes, typically high density polyethylene (HDPE), can be pulled-into-place, avoiding traditional cut-and-cover construction, using pipe bursting and horizontal directional drilling (HDD) pipe installation techniques. Of particular interest, are the ground displacements, induced by cavity expansion, associated with these techniques and the strains that develop in existing pipes in response to these displacements. Further, the axial stress-strain response of the new HDPE pipe during and after the cyclic pulling force history required to pull the pipe into place is of interest.
	Surface displacements and strains in an adjacent polyvinyl chloride (PVC) pipe induced by static pipe bursting were measured during the replacement of a new unreinforced concrete pipe. For the pipe bursting geometry tested, the maximum vertical surface displacement measured at the ground surface was 6 mm, while the distribution of vertical surface displacements extended no more than 2 m on either side of the centreline. The maximum longitudinal strain measured in the PVC pipe was less than 0.1% and its vertical diameter decreased by only 0.5%, suggesting that pipe bursting did not jeopardize the long-term performance of the water pipe tested.
	In addition, results from identical stress relaxation and creep tests performed on whole pipe samples and coupons trimmed from a pipe wall were compared, and these demonstrated that the coupons exhibited higher modulus than the pipe samples. Therefore, isolated pipe samples, as opposed to coupons, were tested to quantify the stress-strain response of HDPE pipe during the simulated installation, strain recovery, and axial restraint stages of HDD. Axial strains were found to progressively accumulate when an HDPE pipe sample was subjected to the cyclic stress history used to simulate an HDD installation. It was shown that existing linear and nonlinear viscoelastic models can serve as predictive design tools for estimating the cyclic strain history of HDPE pipe during installation. For the specific conditions examined, the tensile axial stresses redeveloped in the pipe samples, once restrained, were not large enough to lead to long-term stress conditions conducive to slow crack growth even when the short-term performance limits were exceeded by a factor of 1.5.

abstract: PhD


title: The Impact of Pedagogical Practice On Student Interest In Elementary Science Classrooms

contributor:
Freeman, John G.
Education

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subject:
Science Education
Interest
Elementary Science
Attitudes toward science
Situational Interest

abstract: Thesis (Master, Education) -- Queen's University, 2009-04-09 11:04:44.967

abstract:
Using a mixed-method design, the purpose of this research was to understand interest in the elementary science classroom as affected by different teaching methods. Of particular concern was the state of interest in junior level (Grades 4-6) science classrooms. Research conducted on science interest and attitudes toward science has identified significant declines in student interest and engagement across grade levels. To remedy these concerns, it has become imperative that researchers and science educators gain a greater understanding of the growing literature in the field of interest and how this research might improve student engagement, especially at the elementary level.

Questionnaires were administered to 178 students from Grades 4-6 measuring their individual interest in science, the frequency at which they were exposed to different teaching methods in science, and the level of interest they held for each instructional approach in science class. In addition, student interviews were conducted with six students from both genders representing each grade to better understand what makes for interesting and effective teaching of science in the eyes of the students. The quantitative and qualitative components yielded largely similar findings. Results indicated that passive learning tasks, such as written work and note taking, became less popular as grade level increased, that female students maintained a greater interest in passive learning tasks than males, and that passive learning tasks had the greatest impact on predicting student interest in science. Furthermore, students reported that they were best engaged by instructional strategies that were characterized by experimentation, cooperation, relevance, and novelty. These results were used to shed light on previous research in the field, and to suggest directions for future research and practice.

abstract: M.Ed.


title: CFRP Tendons For The Repair Of Post-Tensioned, Ubonded Concrete Buildings

contributor:
Green, Mark F.
MacDougall, Colin
Civil Engineering

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subject:
CFRP Tendons
Post-Tensioning
Field Application
Unbonded
Prestressed

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2009-04-09 15:30:59.865

abstract:
The deterioration of prestressed concrete structures due to corrosion is a costly problem.  This problem is accelerated in cold weather climates where de-icing salts are used.  These salts accelerate the corrosion of the steel tendons greatly reducing the service life of the structures and leading to constant costly repairs.  Recent research has shown composite materials such as Fibre Reinforced Polymers (FRP) to be suitable alternatives to steel, providing similar strength without being susceptible to electrochemical corrosion.  Carbon FRP in particular has great promise for prestressed applications, showing resistance to corrosion in environments that might be encountered in concrete and experiencing less relaxation than steel.

This thesis outlines the testing and implementation of a post-tensioned system that uses CFRP tendons to replace corroded, unbonded post-tensioned steel tendons.  This system was then implemented in a parking garage in downtown Toronto.  To the author’s knowledge, this is the first example of an unbonded, post-tensioned tendon replacement using FRP tendons.  The system used split wedge anchors designed specifically for CFRP tendons at the University of Waterloo.  The dead end was anchored by directly bonding the tendon to the concrete slab.  Overall, the system was shown to work and provide a durable solution for unbonded post-tensioning systems. The CFRP tendon was successfully inserted in the opening left by the removal of the corroded tendon and stressed.  It was found that the current anchorage configuration experienced large load losses of up to 60 % during the transfer.  Changing the orientation of the anchor was found to reduce the load lost to a range of 1 % to 9 %.

abstract: M.Sc.


title: The tectonometamorphic evolution of the Greater Himalayan sequence as exposed in central Nepal and adjacent south-central Tibet

contributor: Geological Sciences and Geological Engineering

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subject:
geology
tectonics
Himalaya
Tibet
structural geology

abstract: Thesis (Ph.D, Geological Sciences & Geological Engineering) -- Queen's University, 2009-04-13 11:48:45.702

abstract:
Understanding the development of the Himalaya is critical to elucidating continental collisional processes.  The Greater Himalayan sequence (GHS), the exhumed mid-crust of the Himalayan orogen, records the tectonometamorphic evolution of the Himalaya from its deep hinterland to its foreland. The GHS in central Nepal and adjacent Tibet is deformed pervasively; quartz c-axis orientation fabrics from across the GHS indicate that it was deformed at high temperatures (~550-650˚C). The asymmetries of these quartz c-axis fabrics confirm field observations that define a reversal in shear sense from top-south shear near the bottom and middle of the GHS to top-north shear near the top of the package proximal to the South Tibetan detachment system (STDS). Estimates of mean kinematic vorticity from across the GHS indicate a pure shear contribution between 33% and 67%.
	U-Pb geochronologic data from the upper GHS exposed in the Changgo culmination in south Tibet indicate that melt crystallization and metamorphism related to crustal thickening occurred at ca. 35 Ma and was succeeded by a second metamorphic episode and syn-kinematic voluminous anatexis at ca. 22 Ma.  The upper GHS was thinned vertically by 50% and extended horizontally during and immediately after the second metamorphic event, in a manner typical of the deep hinterland regions of orogens.
	In central Nepal, the ductile lateral extrusion of the upper GHS between the Main Central thrust (MCT) below and STDS above ceased by ~19 Ma.  The cessation of lateral extrusion followed the collapse of the orogenic wedge and a reduction in the gravitational potential necessary to drive the propagation of deformation southwards towards the foreland.  To restore the geometry of the wedge, deformation stepped out-of-sequence into southern Tibet, with the exhumation of the Changgo culmination and the North Himalayan antiform, before migrating incrementally back toward the foreland. Subsequently, the MCT migrated downward structurally adding material to the lower GHS as thrust slices, characteristic of foreland-style deformation. Thus, the transition between the upper and lower GHS in central Nepal records the transition from hinterland-style deformation to foreland-style deformation.

abstract: PhD


title: The Alignment of Knowledge Strategies

contributor:
Chan, Yolande E.
Management

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subject:
Strategic Alignment
Knowledge Strategy

abstract: Thesis (Ph.D, Management) -- Queen's University, 2009-04-12 16:39:28.315

abstract: This thesis is a collection of four manuscripts linked by the aim of extending strategic alignment thought into the knowledge management domain by explicitly including the concept of knowledge strategy into the discussion of strategic alignment. In the first paper, a set of common knowledge strategy dimensions was synthesized and used to link two existing knowledge strategy typologies. The key finding of the study was that the two typologies operated at different strategic levels, allowing for the creation of portfolios of the lower order types under each higher order type. In the second paper, a model of strategic alignment between business, information system and knowledge strategy was presented and tested using survey data. It was found that the combination of aligned information and knowledge strategies with their associated business strategy resulted in higher performance for defenders, analyzers and prospectors and that the alignment of non-viable strategies led to worse performance than individual non-viable strategies alone. In the third paper, case studies provided examples of alignment and misalignment which were used to populate a framework linking alignment and performance. Four explanations for firms’ location in the model were provided, focusing on appropriate versus inappropriate alignment, conscious versus unconscious misalignment, antagonistic alignment versus misalignment, and strategic alignment versus misalignment. In the final paper, the Strategic Orientation of Knowledge-Based Enterprises (STROKE) instrument was developed to capture the orientation of knowledge strategy employment in firms. During the development process, a new statistic was developed to aid in the validation of card sorts during the scale development step of instrument creation.

abstract: PhD


title: Incorporation of Polar Comonomers Into High Density Polyethylene With a Cyclopentadienyl-Amido Titanium Catalyst

contributor:
Baird, Michael C.
Chemistry

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subject:
polymer
polyethylene
titanium
constrained geometry
cyclopentadienyl-amido
copolymerization
polar comonomer

abstract: Thesis (Master, Chemistry) -- Queen's University, 2009-04-27 10:16:46.356

abstract:
The purpose of this research was to synthesize the constrained geometry catalyst Ti[(C5Me4)SiMe2(tBuN)]Cl2 (1) with MAO as a cocatalyst for ethylene homopolymerization and copolymerizations with 1-TMSO-alkenes to produce a copolymer with polar functionality.  Three 1-alkenols of varying length were purchased and derivatized and used for the copolymerization experiments: 2-propen-1-ol, 3-buten-1-ol and 9-decen-1-ol.  Several variables were tested to determine their effects on comonomer incorporation such as temperature, equivalents of comonomer, equivalents of MAO and two different solvents.  Higher catalytic activities were correlated with fewer equivalents of polar comonomer, lower temperatures, and no fewer than 1000 equivalents of MAO.  Toluene was found to be a far more effective reaction solvent than dichloromethane, as polymer yields were on average thirteen times higher.

All polymer samples were analyzed by high temperature 1H NMR spectroscopy and selected samples were analyzed by DSC and IR spectroscopy.  DSC determined that the polyethylene produced by 1 was substantially linear HDPE with long chain branching and that comonomer incorporation reduced the Tc and Tm, probably due to increased short chain branching.  1-TMSO-9-Decene was the most effective comonomer, as it had the highest incorporation rates (8.0 mol%) of all three of the polar comonomers.  The two shorter comonomers exhibited no incorporation at all.  This confirmed the hypothesis that polar comonomers with longer chains would be less prone to poisoning the electrophilic catalyst.

abstract: M.Sc.


title: MOSFET Current Source Gate Drivers and Topologies for High Efficiency and High Frequency Voltage Regulator Modules

contributor:
Liu, Yan-Fei
Sen, Paresh C.
Electrical and Computer Engineering

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subject:
Current Source Driver
Voltage Regulator Module (VRM)
dc dc
Zero-Voltage-Switching

abstract: Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-04-23 08:59:12.699

abstract:
With fast development of semiconductor industry, the transistors in microprocessors increase dramatically, which follows the Moore’s law. As a result, the operating voltages of the future microprocessors follow the trend of decreasing (sub 1V) while the demanding currents increase (higher than 100A). Furthermore, the high slew rates during the transient will reach 1200 A/us. All these impose a serious challenge on a Voltage Regulator (VR) or Voltage Regulator Module (VRM). In order to meet requirements of the next generation microprocessors, four new ideas are proposed in this thesis.
The first contribution is an accurate analytical loss model of a power MOSFET with a Current-Source Driver (CSD). The impact of the parasitic components is investigated. Based on the proposed loss model, a general method to optimize the CSD is presented. With the proposed optimization method, the CSD improves the efficiency from 79.4% using the conventional voltage source driver to 83.6% at 12V input, 1.5V/30A output and 1MHz.
The second contribution is a new continuous CSD for a synchronous buck converter. The proposed CSD is able to drive the control and Synchronous Rectifier (SR) MOSFETs independently with different drive currents enabling optimal design. At 12V input, 1.5 V/30A output and 1MHz, the proposed CSD improves the efficiency from 79.4% using a conventional voltage source driver to 83.9%.
The third contribution is a new discontinuous CSD. The most important advantage of the new CSD is the small inductance (typically, 20nH at 1MHz switching frequency). A hybrid gate drive scheme for a synchronous buck converter is also proposed. The idea of the hybrid gate driver scheme is to use the CSD to achieve switching loss reduction for the control MOSFET, while use the conventional voltage source driver for the SR. At 12V input, 1.3V/25A output and 1MHz, the proposed CSD improves the efficiency from 80.7% using the voltage source driver to 85.4%.
The final contribution is new self-driven zero-voltage-switching (ZVS) non-isolated full-bridge converters for 12V input VRM applications. The proposed converter achieves the duty cycle extension, ZVS operation and SRs gate energy recovery. At 12V input, 1.3V output and 1MHz, the proposed converter improves the efficiency from 80.7% using the buck converter to 83.6% at 50A.

abstract: PhD


title: Multi-Scale Modelling of Texture Evolution and Surface Roughening of BCC Metals During Sheet Forming

contributor:
Pilkey, A. Keith
Diak, Bradley J.
Mechanical and Materials Engineering

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subject:
Crystal Plasticity
Modelling
bcc metals
Surface Roughness
Dislocation Theory
Strain Path

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2009-04-15 11:51:04.518

abstract:
This thesis examines the qualitative and quantitative variation in local plastic deformation and surface roughening due to crystallographic texture in body-centered cubic materials, specifically interstitial-free steel sheet and molybdenum foil and sheet. Complex forming operations currently used in industrial manufacturing lead to high material failure rates, due in part to the severity of the applied strain path.

A multi-scale model was developed to examine the contribution of mesoscopic and local microscopic behaviour to the macroscopic constitutive response of bcc metals during deformation.  The model integrated a dislocation-based hardening scheme and a Taylor-based crystal-plasticity formulation into the subroutine of an explicit dynamic FEM code, LS-DYNA.

Numerical analyses using this model were able to predict not only correct grain rotation during deformation, but variations in plastic anisotropy due to initial crystallographic orientation.  Simulations of molybdenum foil under uniaxial tension supported the existence of bending due to local variations in plastic anisotropy, confirmed with good quantitative agreement by experimental measurements of surface roughening.

A series of two-stage strain-path tests were performed, revealing a prestrain-dependent softening of both the steel and molybdenum samples when an orthogonal secondary strain path is applied.  Numerical analyses of these tests overestimate macroscopic hardening during complex loading, due in part to the dynamic nature of the FEM code used.

abstract: PhD


title: Generalisation of adaptation to a visuomotor rotation from curved to straight line reaching

contributor:
Flanagan, J. Randall
Psychology

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subject:
motor learning
visuomotor perturbation
reach planning

abstract: Thesis (Master, Psychology) -- Queen's University, 2009-04-16 15:42:40.872

abstract:
Numerous studies have investigated motor learning by examining the adaptation
of reaching movements to visuomotor perturbations that alter the mapping between actual
and visually perceived hand position. The picture of the visuomotor transformation from
visual input to motor input that has developed consists of three broad phases: integration
of hand and target locations in a common reference frame, calculation of a movement
vector between hand and target, and transformation of this movement vector from the
common reference frame into motor commands. The process of adapting to a visuomotor
rotation is generally viewed as an alteration of the vectorial representation of reach
planning. When visual feedback is rotated, the motor and visual directions no longer
coincide and the motor command executed is remapped to the subsequent visual direction
produced. In the current set of studies, we examined how learning a visuomotor rotation
while reaching to a target with a curved hand path generalizes to straight path reaching
and novel target directions. We found that there is very little to no generalization of
learning between curved reaches and straight reaches when given only endpoint
feedback. With continuous visual feedback, we found partial transfer. This suggests that
in the absence of visual feedback, the vectorial adaptation hypothesis is insufficient and
adaptation to a visuomotor rotation is mediated by the later stages of the visuomotor
transformation, when the motor commands specific to the hand path used are being
generated.

abstract: M.Sc.


title: The Phenomenology of Role Play: Are Children “Thinking-As-If” or “Behaving-As-If”?

contributor:
Sabbagh, Mark A.
Psychology

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subject:
Pretend Play
Theory of Mind

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2009-04-15 17:02:11.029

abstract: When children role play, they do things such as change their tone of voice or take on the character’s emotions or needs. These behaviours make it appear as though children adopt the mental perspective of the character they are pretending to be, which has led some researchers to argue that children “think-as-if” they are the character while role playing (e.g., Harris, 2000). However, it is questionable whether these sorts of behaviours can really be taken as strong evidence that children are “thinking-as-if”; children might simply be imitating the distinctive behavioural characteristics of the character they are pretending to be – or “behaving-as-if”. In two studies, I attempted to obtain better evidence that children “think-as-if” while role playing. To do this, I developed a novel paradigm called the Pretend Self-recognition (PSR) task that examines how children refer to photographs of themselves while they are pretending to be someone else. I reasoned that if children were truly “thinking-as-if”, they might see the photograph of themselves as a third person would, and thus refer to the photograph of themselves using their own proper name. In contrast, if children were simply "behaving-as-if", they might continue to refer to the photograph with the personal pronoun “me”. In Study 1, approximately half of 4-year-old children labeled their own photograph from the perspective of the character they were pretending to be, and thus showed evidence of "thinking-as-if". This finding was replicated when children were given the PSR task at two time points along with measures of theory of mind, executive functioning, pretense understanding, and narrative absorption. Results showed that PSR performance was stable across testing period, but was not related to any of the other constructs that were also measured. Taken together, the findings reported in this dissertation show that the PSR task is a reliable measure of perspective taking in role play, though the source of individual differences in the measure remains a target for future research. The lack of relation between individual differences might suggest that PSR performance is orthogonal to the other constructs and is something in its own right.

abstract: PhD


title: Controlled Synthesis of Stimuli-Responsive Network Alginate

contributor:
Neufeld, Ronald J.
Chemical Engineering

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subject: Semisynthesis Alginate Hydrogel Acetalization Diffusion Swelling

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2009-07-20 11:48:17.508

abstract:
Stimuli-responsive hydrogels swell or contract in response to external pH, ionic strength or temperature, and are of considerable interest as pharmaceutical controlled release devices. Alginate, a linear polysaccharide consisting of mannuronic and guluronic acids, was used as starting material in semisynthesis of pH-responsive hydrogel. Linear alginate was chemically modified with di-aldehyde via acid-catalyzed acetalization, forming a tetrafunctional acetal-linked semisynthetic network alginate polymer (SNAP) with carboxylate moieties preserved as stimuli-responsive sensors. The kinetics of acetalization were found to undergo zero and second-order reaction with respect to di-aldehyde and alginate respectively. With the determined rate constant of 19.06     L•mole-1•s-1 at 40oC and activation energy of 78.58 kJ•mol-1, a proposed predictive reaction model may be used a priori to select reaction conditions providing specific polymer properties. Gel swelling and average pore size were then able to be kinetically or thermodynamically controlled between 80-1000 fold and 30 nm-1 m respectively. As a proof of concept, SNAP hydrogel was fine-tuned with specific swelling and pore sizes for absorptive encapsulation and controlled release of a wide spectrum of molecular sizes of proteins ranging between 1.3 to 546 kDa. SNAP hydrogels/granules demonstrated limited swelling in the simulated gastric environment, protecting proteins from enzymatic and acid degradation, while swelling in alkaline media, releasing active therapeutics in a simulated intestinal lumen (pH ~ 7.8), so is under the consideration as an oral delivery vehicle for protein therapeutics.
A constitutive polyelectrolyte gel model based on non-Gaussian polymer elasticity, Flory-Huggins liquid lattice theory, and non-ideal Donnan-membrane equilibria was derived, to describe SNAP gel swelling in dilute and ionic solutions. The derived model accurately describes the SNAP hydrogel swelling in acid and alkaline solutions of wide range of ionic strength. The pore sizes of SNAP hydrogel were estimated by the derived model and were comparable to those determined experimentally by thermoporometry and protein diffusion. The derived model can characterize hydrogel structure such as molecular weight between crosslinks, or can be used as predictive model for swelling and pore size if gel structural information is known, and can potentially be applied to other point-link network polyelectrolytes such as hyaluronic acid gel.

abstract: PhD


title: (Mis-)Understanding Anti-Semitism and Jewish Identity: From Bernard Lazare to Hannah Arendt

contributor:
Mah, Harold
History

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subject:
Modern European Intellectual History
European Intellectuals
Anti-Semitism
Jewish Identity
Bernard Lazare
Marcel Proust
Frankfurt School
Hannah Arendt
Dreyfus Affair
The Holocaust

abstract: Thesis (Ph.D, History) -- Queen's University, 2009-04-16 08:34:25.821

abstract: This study examines the responses of European intellectuals since the 1880s to an increasingly virulent and organized anti-Semitism in Europe, and the ways in which they sought to understand the character and origins of the hatred, and to fathom and work out the problems, terms and possibilities for Jewish identity. Focusing on the French figures Bernard Lazare and Marcel Proust from the time of the Dreyfus Affair and then on the Frankfurt School of social theory and Hannah Arendt from the period around and after the Second World War, the thesis argues that these thinkers created a common historical-psychological discourse on anti-Semitism, which attempted to confront, comprehend and explain the historically critical issues of anti-Semitism and Jewish identity. The study explores the discourse’s fundamental assumptions, insights, and arguments regarding the origins, character, and magnitude of anti-Semitism. It also analyzes its contentions concerning the contradictions, sources, and alternatives for Jewish identity. But, more, it claims that, despite their frequent perceptiveness, these figures’ interpretations of the two concerns proved limited, deficient, even deeply flawed. The thesis seeks to show that its intellectuals’ attempt to understand the twin issues was hence a failure to grasp and interpret them adequately, and to resolve them. It contends further that what impaired the authors’ engagements with anti-Semitism and Jewish selfhood were ideas that were fundamental to their thinking. These intellectual factors, moreover, connected the figures solidly to important historical contexts that they inhabited, thereby implicating the significant settings in the epistemological errors and defeats. These momentous ideas thus operated as both contextualizing and destructive forces—linking the intellectuals to their home contexts and transforming their understanding of their historic problematic into a misunderstanding.

abstract: PhD


title: Multi-Regional Analysis of Contact Maps for Protein Structure Prediction

contributor:
Glasgow, Janice I.
Computing

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subject:
Protein Structure
Contact Map
Sequence Similarity
Protein Homology

abstract: Thesis (Master, Computing) -- Queen's University, 2009-04-23 22:01:04.528

abstract:
1D protein sequences, 2D contact maps and 3D structures are three different
representational levels of detail for proteins. Predicting protein 3D
structures from their 1D sequences remains one of the complex challenges of
bioinformatics. The "Divide and Conquer" principle is applied in our
research to handle this challenge, by dividing it into two separate yet
dependent subproblems, using a Case-Based Reasoning (CBR) approach. Firstly,
2D contact maps are predicted from their 1D protein sequences; secondly, 3D
protein structures are then predicted from their predicted 2D contact maps.
We focus on the problem of identifying common substructural patterns of
protein contact maps, which could potentially be used as building blocks for
a bottom-up approach for protein structure prediction. We further
demonstrate how to improve identifying these patterns by combining both
protein sequence and structural information. We assess the consistency and
the efficiency of identifying common substructural patterns by conducting
statistical analyses on several subsets of the experimental results with
different sequence and structural information.

abstract: M.Sc.


title: Theory, Research, and Practice: Developing a Model for Teaching Mathematics

contributor:
Johnston, Scott
Education

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subject:
Dewey, John
Math Learning Disability

abstract: Thesis (Master, Education) -- Queen's University, 2009-04-16 19:58:52.504

abstract: Dewey provides a rich context in which to develop an understanding of education as growth. By developing an understanding of education as growth, educational research can be incorporated into that context so that a more comprehensive model of education may be considered. Education as growth suggests that education is about progress rather than end states. The knowledge and skills of inquiry must be understood as part of an interconnected whole that includes the physical, social, and intellectual growth of the individual and the community. The role of inquiry in the development of concepts and habits that foster the intellectual and cultural growth of the individual and community are discussed. The work of researchers on math learning disabilities is presented and examined in light of Dewey’s concepts of growth and inquiry so that the educational needs of students with math learning disabilities might be included in a model of education. The quality of the educational experiences of students with math learning disabilities has significant implications for the growth and development of all students, parents, teachers, researchers, and the community.

abstract: M.Ed.


title: Anthropometric Markers of Health Risk

contributor:
Katzmarzyk, Peter T.
Janssen, Ian
Kinesiology and Health Studies

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subject:
Obesity
Epidemiology
Measurement
Body composition
Risk factors
Diabetes
Mortality
Population

abstract: Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2009-04-17 14:23:44.372

abstract: The objective of this thesis was to investigate the relationships between simple anthropometric measures and health risk towards a better characterization of the high-risk obesity phenotype.  To this end, four studies were undertaken.  The first study assessed the comparability of waist circumference (WC) data collected according to four commonly used measurement protocols in a sample of 520 community-dwelling men and women.  This investigation quantified the influence of measurement site on the magnitude and reliability of WC and highlighted the impact of measurement site on prevalence estimates of abdominal obesity.  To extend these findings, the second study examined the influence of WC measurement site on its association with cardiometabolic risk. Despite similar associations with risk factors including blood pressure, HDL-cholesterol, triglycerides, and blood glucose, prevalence estimates of metabolic syndrome differed depending on the anatomical site of WC measurement, particularly in women.  In order to better understand the heterogeneity in human obesity and its sequelae, the third and fourth studies focused on the separate and combined influences of central and peripheral circumferences on health outcomes.  Specifically, the third study used data from the Physical Activity Longitudinal Study (PALS) to demonstrate that after adjusting for BMI and WC, larger arm, calf, and thigh circumferences offer a protective effect against incident diabetes.  The fourth study confirmed the opposing influences of central and peripheral circumferences on risk of all-cause mortality in a sample of 10,638 participants from the 1981 Canada Fitness Survey (CFS) with more than 12 y of follow-up.  After adjustment for age, smoking status, alcohol consumption, leisure-time physical activity and BMI, WC was positively associated with mortality whereas arm, thigh, and calf circumferences were significantly protective in men and arm and thigh circumferences were protective in women.  Collectively, the results from these studies contribute to a better understanding of the role of body dimensions in determining health risk and have implications for the use of anthropometric measures in clinical and research settings.

abstract: PhD


title: Assessing Public Health Preparedness in Alberta Using a Systems-Level Approach

contributor:
Moore, Spencer
Kinesiology and Health Studies

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subject:
public health preparedness
Alberta
emergency response systems

abstract: Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-04-17 15:58:33.093

abstract:
Recent international and national events such as the SARS outbreak in 2002–2003, the rising incidence of West Nile Virus, and the increasing threat of a pandemic influenza outbreak have brought critical attention to the Canadian public health system and how prepared the system is to respond to various types of contemporary public health threats.  The effective coordination of all agencies at metropolitan, regional, provincial, and federal levels is essential to the management of public health emergencies.

The level of inter-organizational coordination and preparedness of public health and emergency preparedness organizations throughout Alberta was investigated.  An online organizational questionnaire provided a census of organizations involved in public health preparedness, and information on the structure of inter-organizational relations in Alberta and the state of public health preparedness from the perspective of organizational members.  The primary goal was to use the information provided by individual agencies to help improve how policymakers and public health and emergency management officials plan and organize for public health threats and emergencies.

Major findings are as follows: i) organizational characteristics including organizational training opportunities, size, and jurisdiction are associated with different dimensions of organizational-level preparedness in Alberta, ii) perceived organizational connectivity serves as a proxy measure of formal ties objectively reported by organizations with respect to pandemic influenza preparedness, iii) higher jurisdictional organizations display greater degrees of interconnectedness on average, and iv) organizational connectivity moderates the association of perceived public health preparedness with an organization’s objective level of preparedness, independent of jurisdictional level.

The true test of public health preparedness is in how the system responds to an actual crisis.  Since public health emergencies are rare, there is an absence of province-wide data in this regard; however, this work has measured organizational-level perceptions of public health preparedness as a proxy for actual preparedness.  It is critical that organizations have a written emergency response plan which is tested in practice through exercises or in a real situation to observe jurisdictional and organizational ability to execute an appropriate response and assess communication and resource flow among organizations.

abstract: M.Sc.


title: Using Code Mutation to Study Code Faults in Scientific Software

contributor:
Kelly, Diane
Computing

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subject:
Mutation Sensitivity Testing
Scientific Software
Software Testing
Mutation Testing
Code Faults
Code Scrutinization
Oracle Problem
Tolerance Problem

abstract: Thesis (Master, Computing) -- Queen's University, 2009-04-19 13:34:08.943

abstract:
Code faults can seriously degrade scientific software accuracy. Therefore, it is imperative that scientific software developers scrutinize their codes in an attempt to find these faults. This thesis explores, particularly, the efficacy of code testing as a method of scientific software code fault detection.

Software engineers, as experts in code quality, have developed many code testing techniques, but many of these techniques cannot readily be applied to scientific codes for at least two reasons. First, scientific software testers do not usually have access to an ideal oracle. Second, scientific software outputs, by nature, can only be judged for accuracy and not correctness. Testing techniques developed under the assumption that these two problems can be ignored--as most have been--are of questionable value to computational scientists.

To demonstrate the reality of these problems and to provide an example of how software engineers and scientists can begin to address them, this thesis discusses the development and application of a novel technique: Mutation Sensitivity Testing (MST). MST is based on traditional mutation testing, but--in place of a focus on mutant "killing"--MST focuses on assessing the mutation sensitivity of a test set.  In this thesis, MST experiments are conducted using eight small numerical routines, four classes of mutation operators, and 1155 tests. The results are discussed and some conclusions are drawn. Two observations are of particular interest to computational scientists. First, it is found that oracles that exhibit uncertainties greater than (approximately) 80% of the expected output are of questionable value when they are used in the testing of scientific software. Second, it is found that a small number
of carefully selected tests may be sufficient to falsify a code.

abstract: M.Sc.


title: Organically Modified Mesoporous Silica as a Support for Synthesis and Catalysis

contributor:
Crudden, Cathleen M.
Chemistry

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subject:
Materials Chemistry
Mesoporous Silica
Supported Catalysis
Heterogeneity Tests
Chiral Periodic Mesoporous Silica

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2009-04-20 10:49:13.443

abstract:
Mesoporous silicates are excellent materials for supported catalysis due to their ease of functionalization, tunable pore size and high surface areas. Mesoporous silicates have been utilized in a variety of applications such as drug delivery scaffolds and catalyst supports. Functionalization of the surface can be achieved by either grafting of alkoxy silanes or co-condensation of the organosilane with the inorganic silica source.
My research in this area can be divided into two components.  In the first, we address the significant issue of metal contamination after reactions that are catalyzed by transition metals.  In the second, we examine the design of new catalysts based on organic/inorganic composites.
Ruthenium catalyzed processes such as olefin metathesis or asymmetric hydrogenation, are often underutilized due to the difficulty of removing the ruthenium by-products. Attempts to remove ruthenium involve treating the solution with a scavenging reagent followed by silica chromatography. Often these scavenging agents are expensive phosphines or toxic agents like lead tetra-acetate. SBA-15 functionalized with aminopropyl triethoxysilane displays a high affinity for ruthenium. Furthermore, it can be utilized to remove ruthenium by-products from olefin metathesis or hydrogenation reactions without the need for silica chromatography.
	We have also prepared sulfur-functionalized mesoporous silicates that have a high affinity for palladium. The materials after loading prove to be active catalysts for a variety of palladium catalyzed processes such as Suzuki-Miyaura and Sonogashira couplings. The catalysts are recyclable with moderate loss of activity and structure, depending on the method of incorporation of the thiol. We have characterized the as-synthesized and used catalysts by nitrogen sorption, TEM, X-ray photoelectron spectroscopy (XPS) and a variety of homogeneity tests were performed on the catalysts.
	Periodic mesoporous organosilicates (PMOs) are a well known class of inorganic-organic hybrid materials. The majority of PMOs prepared utilize simple organic bridges such as ethyl, phenyl or biphenyl. The use of a chiral organic bridging group, such as BINAP, allows the synthesis of chiral PMOs with possible applications in catalysis and separation science. The synthesis of a triethoxysilyl functionalized BINAP as well as its incorporation into PMO materials with 4,4’-bistriethoxysilyl biphenyl or tetraethylorthosilicate as co-silica sources are described.

abstract: PhD