title: Novel Functions of IL-27 in Innate Immunity: Characterization of IL-27-induced Inflammatory Responses in Human Monocytes and Impact of HIV Infection on IL-27 Expression and Function

contributor:
Gee, Katrina
Microbiology and Immunology

subject: cytokine

subject: HIV

subject: interleukin-27

subject: TLR4

subject: monocyte

subject: BST-2

subject: STAT

subject: NF-kappa B

abstract: Thesis (Ph.D, Microbiology & Immunology) -- Queen's University, 2012-04-12 13:07:50.588

abstract: Interleukins, cytokines secreted by leukocytes, are predominant messengers modulating immune responses. Interleukin-27 (IL-27), a key immunomodulatory cytokine, functions to induce both pro- and anti-inflammatory effects in various immune cells. IL-27 is a heterodimeric cytokine, composed of IL-27p28 and Epstein-Bar virus induced gene 3 (EBI3) subunits, and binds to a receptor composed of IL-27Rα (WSX-1) and gp130. Initial studies focused on describing IL-27 functions in skewing T helper cell development to a Th1 response, with few reports on functions in monocytes. Thus, in this thesis, I aimed to characterize novel functions of IL-27 in innate immune responses of monocytes. I initially established that IL-27 induced a pro-inflammatory cytokine profile (IL-6, IP-10, MIP-1α, MIP-1β, and TNF-α) mediated via STAT1/3 and NF-κB signaling pathways. Further investigation led to the discovery that IL-27 could enhance LPS responses via upregulation of TLR4 expression and NF-κB signaling. Together, these studies described novel signaling mechanisms (NF-κB and JAK/STAT crosstalk) and gene targets (cytokines and TLR4) of IL-27 that drive inflammatory responses. In continuing the quest for novel IL-27 functions in innate immunity, I reported IL-27 can upregulate expression of the IFN-responsive, antiviral protein called BST-2. My results showing IL-27-induced expression of BST-2 mRNA and cell surface protein were supported by previous studies reporting IL-27-induced expression of other antiviral molecules. Furthermore, previous studies showed IL-27 could inhibit HIV replication via antiviral gene induction, pointing to potential for IL-27 immunotherapies. In light of the posited role for IL-27 in therapeutics, it became inherently critical to describe how IL-27 functions in the setting of HIV infection. Thus, in my final thesis chapters, I described the effect of HIV infection on IL-27 expression and functions, addressing a substantial void in literature. Interestingly, a trend of decreased IL-27 expression and significant impairment of IL-27-induced gene expression was observed in HIV infection. Therefore, decreased circulating IL-27 and decreased IL-27 responsiveness may collectively dysregulate IL-27 function in HIV. This thesis describes novel, IL-27-driven, proinflammatory responses, and highlights impairment of IL-27 function in HIV infection. This work bridged a gap in knowledge of IL-27 functions in monocytes and highlighted multifaceted mechanisms underlying immunoregulation by IL-27.

abstract: To retain rights of publication

abstract: PhD


title: Generalization of Ruderman's Problem to Imaginary Quadratic Fields

contributor:
Murty, Maruti Ram
Mathematics and Statistics

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:
Exponential Diophantine equations
Number theory
ABC conjecture
Schmidt's Subspace theorem
Mathematics
Diophantine Equations

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2012-04-13 12:04:14.252

abstract: In 1974, H. Ruderman posed the following question: If $(2^m-2^n)|(3^m-3^n)$, then does it follow that $(2^m-2^n)|(x^m-x^n)$ for every integer $x$? This problem is still open. However, in 2011, M. R. Murty and V. K. Murty showed that there are only finitely many $(m,n)$ for which the hypothesis holds. In this thesis, we examine two generalizations of this problem.  The first is replacing 2 and 3 with arbitrary integers $a$ and $b$.  The second is to replace 2 and 3 with arbitrary algebraic integers from an imaginary quadratic field.  In both of these cases we have shown that there are only finitely many $(m,n)$ for which the hypothesis holds.  To get the second result we also generalized a result by Bugeaud, Corvaja and Zannier from the integers to imaginary quadratic fields.  In the last half of the thesis we use the abc conjecture and some related conjectures to study some exponential Diophantine equations.  We study the Pillai conjecture and the Erd\"{o}s-Woods conjecture and show that they are implied by the abc conjecture and that when we use an effective version, very clean bounds for the conjectures are implied.

abstract: PhD


title: A Parallel-Series Two Bridge DC/DC Converter for PV Power Conditioning Systems Used in Hybrid Renewable Energy Systems

contributor:
Jain, Praveen K.
Electrical and Computer Engineering

subject:
MPPT
DC-Link Voltage Regulation
PV-PCS
Decoupled Output and Input Controller
Two Degree of Freedom DC-DC Converter
Full Bridge Phase-Shift
HRES
DG
DC/DC Converter
Renewable Energy

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-04-18 19:51:43.405

abstract: This thesis presents a parallel-series two-bridge DC/DC converter topology with the ability to operate with ZVS over a wide input and load range. The intended application is power conditioning systems (PCS) of photovoltaic (PV) arrays used in hybrid renewable energy system architectures. The proposed topology provides two degrees of freedom which allows the PV-PCS to regulate the DC-link voltage, while tracking the maximum power point (MPP) of the PV array. This topology distributes the main power into two bridges and the phase-shift between the two bridges and provides another degree of freedom for the PCS to track the MPP. The proposed topology is also able to achieve soft-switching over a wide range. The power conditioning system shows a modular structure to efficiently transfer the power to the load as the main power is divided between two bridges. In addition, the proposed control scheme provides complete decoupling between the input side controller from the output side controller in order to perform MPPT and regulate the the DC-link voltage simultaneously. A 2kW Experimental prototype has been provided to validate the feasibility and performance of the converter. Experimental results prove that the converter is able to regulate the DC-link voltage and track the maximum power extracted from the PV array simultaneously.

abstract: My supervisor and I elect to restrict publication in order to obtain a patent which may arise from the research

abstract: M.A.Sc.


title: A Diesel-Fuelled Solid Oxide Fuel Cell (SOFC) 1 kW Generator: System and Component Studies

contributor:
Peppley, Brant A.
Chemical Engineering

subject:
SOFC
fuel processing
reforming
fuel cells
diesel
process simulation
CFD

abstract: Thesis (Master, Chemical Engineering) -- Queen's University, 2012-04-18 01:12:27.072

abstract:
A steady-state simulation of a diesel-fuelled SOFC system was developed using a process simulation software package (VMGSim).  The system was studied by conducting a sensitivity analysis of six independent variables (steam to carbon ratio, oxygen to carbon ratio, fuel utilization, air utilization, reformer pre-heater approach temperature and cathode temperature to the SOFC) and their effect on three response variables (net system efficiency, stack efficiency, system exhaust temperature).  The steam to carbon ratio, fuel utilization and air utilization were the most influential independent variables and thus affected the greatest change in the performance metrics.  Secondly, a multi-variable study was carried out on the most influential variables and constrained optima for the efficiencies (45% net system, 47% stack) and system exhaust temperature (78 degrees Celsius) were obtained.
For the second part of this work, a steam reforming heat-exchange reactor was modeled using COMSOL.  The reactor performance was assessed on the basis of selectivity and residence time for a given conversion.  Both the kinetic models of Parmar et al. (2010) and Shi et al. (2009) for catalytic diesel steam reforming were applied and compared.  Differences in performance were attributed to differences in the catalyst support and the reaction mechanisms used for deriving the reforming rate expressions.  Finally, a proof of concept multi-scale modeling and design tool was developed by integrating the CFD model with the process simulation.  Two-way communication between four different software components; COMSOL, VMGSim, Matlab and Microsoft Excel was achieved.

abstract: M.A.Sc.


An Analysis of Water Quality and Human Health Issues in First Nations Communities in Canada


title: Native Studies in Ontario High Schools: Revitalizing Indigenous Cultures in Ontario

contributor:
Godlewska, Anne
Geography

subject:
Indigenous Cultural Revitalization
Aboriginal
Education
Native Studies
Ontario High Schools

abstract: Thesis (Master, Geography) -- Queen's University, 2012-04-18 18:20:07.041

abstract:
I hypothesize that specific aspects of education are central to the revitalization of culture amongst Aboriginal peoples in Ontario, and that this revitalization is integral to cultural continuity. I will show the relationship between key aspects of education and cultural revitalization as I track and assess the impacts of Ontario's high school Native Studies suite of courses. The key aspects are: the ability to generate and control content, the content itself (who it targets and serves and how it is applied) and how innovative ideas are implemented, through what processes and with whose help.
 	Recent trends emerging from the analysis of Ontario Ministry of Education (OME) data on the implementation of its suite of ten Native Studies high school courses suggest that the consistent efforts of several generations of First Nations, Métis and Inuit educators working behind the scenes since the late 1960s have resulted in significant and meaningful increases in the number of Native Studies courses offered, the number of schools and school boards offering them, and the number of students enrolling.
	Considering the context of Aboriginal education in Ontario since the 1960s these general results may certainly be interpreted as progressive. I discuss seven catalysts that have had an indisputable influence over the ability of Indigenous educators to exercise an increasing degree of control over the Ontario Ministry of Education Native Studies curricula.  While acknowledging the perspectives of scholars such as Taiaiake Albert, Maria Battiste, Pamela Palmater and Marie Brant-Castellano who argue for “Indian control of Indian education” based on the inherent right of Indigenous peoples to self-government - enshrined in Canada’s “Constitution Act” (1982) - my findings indicate that, given the resources and opportunity to lead the creation of Native Studies courses in Ontario, many Indigenous educators, leaders and communities have opted to take proactive roles in the process, all the while participating in the struggle for the Indigenous constitutionally-inherent right to control all aspects of their education. I argue that we are seeing a resurgence of Indigenous cultures in Canada, and more particularly in Ontario.

abstract: M.A.


SOIL PROPERTIES OF FOREST-GRASSLAND ECOTONES IN SOUTHWEST YUKON


title: Assessing the Effectiveness of Palliative Chemotherapy for Non-Small Cell Lung Cancer: a Phase IV Study of Patients Treated at Ontario’s Cancer Centres

contributor:
Mackillop, William J.
Zhang-Salomons, Jina
Community Health and Epidemiology

subject:
Non-Small Cell Lung Cancer
Phase IV Study
Quality of Life
Palliative Chemotherapy

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-04-23 11:53:33.491

abstract:
Background:  Randomized controlled trials (RCTs) are the gold standard for assessing the efficacy of a medical treatment.  However, the efficacy demonstrated by trials does not automatically translate into a comparable level of effectiveness in the real world.  RCTs may vary from routine clinical practice in several ways; the patients themselves, the delivery of the treatment, and the collateral care provided during treatment.  Phase IV studies that assess outcomes of a treatment in the real-world provide a mechanism for assessing treatment effectiveness.
Objectives:  The objectives of this study were to: describe the characteristics of patients receiving standard, first-line, palliative, platinum-doublet chemotherapy (PPDC) for non-small cell lung cancer (NSCLC) in routine care; describe the effectiveness of PPDC in terms of wellbeing and symptom control; identify patient characteristics associated with change in wellbeing with treatment; and compare reported treatment efficacy to the effectiveness observed in the current study.
Methods:  This study was a retrospective cohort study of patients treated at Ontario’s Regional Cancer Centres (RCCs).  Patients’ Edmonton Symptom Assessment System (ESAS) scores were used to describe patients’ symptomatic status and wellbeing.  The proportions of patients whose wellbeing improved, remained stable or deteriorated at two months were calculated.  Using logistic regression, patient and disease characteristics were assessed for association with change in wellbeing at two months (dichotomized as improved/stable and deteriorated).  In comparing trial results to this study, adjustments were made for differences in case mix.
Results:  Patients’ median age was 65, 55% were male and the majority had stage IV disease and adenocarcinoma histology.  Patients’ baseline wellbeing and symptomatic status varied widely.  61.3% (95% CI: 55.8 – 66.6%) of patients had improved or stable wellbeing at two months.  Histology and baseline wellbeing score were associated with change in wellbeing at two months.
The case mix adjusted estimates of the proportion of improved/stable patients (60.0% (95% CI 54.5 – 65.3) and 60.5% (95% CI 54.9 – 65.6)) were consistent with the proportion of patients achieving general quality of life improvement or stabilization in RCTs (55% and 63%).
Conclusion:  The effectiveness of PPDC delivered in Ontario’s RCCs is consistent with that expected based on the results of RCTs.

abstract: M.Sc.


title: Local and Landscape Variables Influencing the use of Ponds by Wood Frogs (Lithobates sylvaticus) in the Shakwak Valley, Yukon

subject:
Habitat Selection
Local and Landscape-scale


title: Organic Farming in India: Problems and Potential

subject:
Organic Farming
India

abstract: Over the past ten years, the organic farming movement has rapidly expanded in India and worldwide. Throughout the twentieth century, organic farming movements developed in various places around the world in response to the ecological and social destruction caused by industrial agriculture. Primarily, increasing consumer demand in Europe and North America has fuelled the recent consolidation of a global organic farming movement and encouraged its rapid growth. In light of its increasing popularity, organic farming requires further policy attention and research. In particular, it is important that organic farming be considered for its potential as a rural development strategy. In examining the role of the organic farming movement in India, this paper argues that organic farming in India has the potential to improve livelihoods, provide food security and food sovereignty, and serve as part of a climate change mitigation and adaptation strategy. However, there are many obstacles and limitations to be overcome before organic farming can become a powerful force for change in India. Poor agricultural investment and government support for conventional agriculture, undeveloped domestic markets, and costly and complicated certification processes all pose significant obstacles for organic farmers. The success of the movement hinges on further institutional support, in which the government must play a key role. The conclusions in this paper are drawn from a review of the relevant literature, as well as from correspondence with nine Indian organic farmers, two organizations, and an alternative education centre.


title: A Comparative Analysis of Production and Resource Efficiency: Small versus Large Farms in U.S. Agriculture

subject:
Agriculture
Small scale

abstract:
Increases in human population and consumption have placed unprecedented demands on food systems and natural resources. Consequently, food production systems of the future will not only depend on, but must contribute positively to, healthy ecosystems and resilient communities. Emerging evidence advocates for the importance of small farm agriculture and localized food systems as the means in which to address many of the underlying causes of deteriorating agricultural productivity while aiding in the conservation of natural resources. This study illustrates an alternative to large conventional farming – one that provides evidence of bettering society and preserving the natural environment. Specifically, the alternative to large conventional farming makes use of a land-based perspective, which replaces farm income as the prevailing methodology of farm scale analysis and provides previously non-existing information on agricultural trends in the United States (U.S.).
The findings gleaned from utilizing this land-based perspective suggest that small farms, relative to large farms, produce a comparable amount of food per acre – supported by both direct and indirect measures. In particular, the output value gained for each unit of land input was significantly greater for small farms even though overall production efficiency favoured large farms. Further, while the extent of resource input was lower for small farms, the intensity of use per unit of land was correspondingly greater. Nevertheless, environmental merit was still indicated based on the significant proportion of woodland preserved in small farm landholdings as compared to the minor proportion preserved by large farms. Lastly, while both small and large farms provide a composite of varying social benefit, small farms display the greatest social merit in terms of job provision and public accessibility, both of which are proven to increase the resilience and sustainability of agricultural food systems.


title: Evaluating the representation of ecological features in a protected area network: A Gap Analysis study of the Yukon

subject:
Yukon
gap analysis

abstract: A gap analysis study was conducted to assess the effectiveness of the protected area network in the Yukon Territory, based on the degree of representation of key ecological features.  Protected area (PA) networks that are representative of the ecology over a large region are considered desirable for conservation; however, representative PA networks are challenging to achieve because ecological gaps often exist in the PA network.  Ecological gaps signify conservation shortfalls, which weaken the overall success of the PA network.  To determine if gaps were present in the Yukon’s PA network, five geographic information systems datasets were obtained from a variety of sources, in order to be processed in the gap analysis study of the Yukon.  A comparison index method was employed to evaluate the representation of ecological features from three of the datasets: ecoregions, landcover and wildlife key areas.  In addition, two human disturbance datasets, roads and communities, were used to assess the human footprint across the landscape.  The results illustrated that the human footprint in the Yukon was generally minor; however, the region surrounding the city of Whitehorse was found to have the highest level of human disturbance.  Areas which were disturbed by humans were considered unfavourable for conservation purposes, while regions relatively devoid of human impacts were considerably more desirable.  Regions which displayed low levels of representation of ecological features were also ecologically desirable because these areas represented gaps in the Yukon’s PA network.  Of the 57 ecological features used in this gap analysis study, 51% were not well represented by the current PA network, which highlights that there were substantial ecological gaps.  The most prominent gaps were located in the southeast, central-west and northeast portions of the Yukon.  Less critical gaps were prevalent throughout central Yukon.  The findings also identified which ecological features were inadequately represented.


title: Indigenous People and Québec Identity: Revelations from the 2007 Bouchard-Taylor Commission on Reasonable Accommodation

subject:
Québec
Reasonable Accommodation
Bouchard-Taylor Commission
Identity
Indigenous Peoples
Exclusion

abstract: Thesis (Master, Geography) -- Queen's University, 2012-04-22 18:11:39.47

abstract: Many Indigenous leaders and public figures, as well as scholars of Indigenous culture and history, assert that non-Indigenous ignorance of Indigenous realities has systematically disadvantaged Indigenous peoples in Canada, weakened Canadian society, and makes it impossible to address the conditions of life for Indigenous people in Canada in a sustained or coherent way. Additionally, for many scholars silence and unawareness are deeply linked to colonialism and are implicated in the maintenance of unequal social relations. Drawing from this literature, I contend that in Canada, silence around Indigenous peoples and issues works as a spatial tactic of exclusion. I argue that unawareness is bound up in interests that work to render Indigenous peoples absent from the concerns of modern Canada, and that these interests are deeply intertwined with national and provincial identities such that silences around Indigenous peoples and issues are expressed differently in each Canadian province and territory. This thesis explores the nature of public unawareness of Indigenous realities in Québec. Using the remarkable public voice resource generated by the 2007 Reasonable Accommodation Commission in Québec, a public inquiry into Québec citizens’ opinions about the nature of Québec identity and its relationship to the integration of minorities in the province, I analyze the Commission’s mandate and geographical movements, as well as over 750 written briefs submitted to the Commission. I argue that unawareness of Indigenous realities is widespread in Québec and is unconstrained by participants’ social positions, interests, arguments, or level of engagement with the question of indigeneity in Québec. Though the Commission worked to exclude Indigenous content (and perhaps peoples) from its activities from the outset, eight Indigenous leaders submitted briefs and spoke powerfully and critically of the Commission’s exclusion. These authors point out that the question of Indigenous rights is far from settled, that the Commission’s and Quebecers’ unawareness of Indigenous realities is complicit in a long history of exclusion in Québec and in Canada, and assert that Quebecers will not be able to address their anxiety around immigration in any meaningful or coherent way until Indigenous rights are respected. In my focus on the Reasonable Accommodation Commission, I suggest the particular nature of exclusion in Québec. While exclusion of Indigenous peoples is a Canadian universal, its flavour varies. In this case, the provincial jurisdiction is important.

abstract: M.A.


title: Multi-Scale Modeling and Experimental Study of Deformation Twinning in Hexagonal Close-Packed Materials

contributor:
Daymond, Mark R.
Mechanical and Materials Engineering

subject:
Crystal Plasticity Finite Element
Multi-Scale Modeling
Hexagonal Close Packed Materials
Twinning

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2012-04-23 11:50:33.751

abstract: Zirconium and its alloys have been extensively used in both heavy and light water nuclear reactors. Like other Hexagonal Close-Packed (HCP) materials, e.g. magnesium, zirconium alloys develop different textures during manufacturing process which result in highly anisotropic materials with different responses under different loading conditions. Slip and twinning are two major deformation mechanisms during plastic deformation of zirconium. This dissertation uses various experimental techniques and a crystal plasticity scheme in the finite element framework to study deformation mechanisms in HCP materials with an emphasis on twinning in Zircaloy-2. The current study is presented as a manuscript format dissertation comprised of four manuscript chapters. After a literature review in Chapter 2, Chapter 3 reports steps in developing a crystal plasticity finite element user material subroutine for modeling deformation in Zircaloy-2 at room temperature. It is shown in Chapter 3 that the developed rate dependent equations are capable of capturing evolution of key features, e.g., texture, lattice strains, and twin volume fractions, during deformation by twinning and slip. Chapter 4 reports various assumptions and approaches in modeling twinning where results are compared against neutron diffraction measurements from the literature. It is shown in Chapter 4 that the predominant twin reorientation scheme can explain texture development more precisely than the other schemes discussed. Chapter 5 and 6 are two connected chapters where in the first one the formation of twins is studied statistically and in the second one, local inception and propagation of twins is studied. Numerical results of these two chapters are compared with 2D electron backscattered diffraction measurements, both carried out by the author and from the literature. Results from these two connected chapters emphasize the important role of grain boundary geometry and stress concentration sites on twin nucleation and growth. The four manuscript chapters are followed by summarizing conclusions and suggestions for future work in Chapter 7.

abstract: PhD


title: Sentencing Aboriginal Offenders: The Honour of the Crown, Reconciliation and Rehabilitation of the Rule of Law

contributor:
Walters, Mark D.
Law

subject:
Aboriginal Sentencing
Honour of the Crown
Gladue

abstract: Thesis (Master, Law) -- Queen's University, 2012-04-23 18:41:36.57

abstract:
This thesis argues that the honour of the Crown and the reconciliation agenda are engaged in the sentencing of Aboriginal offenders, given grossly disproportionate Aboriginal incarceration rates and their underlying causes, including socio-economic problems, community breakdown and cultural dislocation that arise at least partly from the history of Crown-Aboriginal interaction.   Such an interpretation facilitates a new relationship between the Crown and Aboriginal peoples and will contribute to the rehabilitation of the rule of law.  I address not only the underlying legal questions pertaining to the engagement of the honour of the Crown and the reconciliation agenda in sentencing Aboriginal offenders, but also interrogatories relating to the role of morality in the law and the rule of law for Aboriginal peoples in the sentencing context.  Fundamentally, the honour of the Crown and reconciliation principles are interpreted and applied such that the sentencing of Aboriginal offenders can accommodate and attempt to ameliorate colonialist history.  This distinctive history produces a legal requirement of reconciliation and honour-based governance if the rule of law is to be a reality for Aboriginal peoples in Canada.

Section 718.2(e) of the Criminal Code and Gladue analysis provide a vehicle for the courts to inject the honour of the Crown into the sentencing of Aboriginal offenders, albeit at one remove.  However, the honour of the Crown requires a vigorous Gladue type analysis by judges sentencing Aboriginal offenders regardless of the existence of section 718.2(e).   Canada must be prepared to accept responsibility and directly address some of the fallout in the criminal justice system from the history of Crown / Aboriginal relations.   The honour of the Crown requires a different sentencing approach for Aboriginal offenders independent of section 718.2(e) and reconciliation is an interpretive normative principle underlying the sentencing of Aboriginal offenders, shaping the honour of the Crown and infusing the rule of law for Aboriginal peoples.  Aboriginal offender rehabilitation needs to go hand in hand with the rehabiltation of the rule of law for Aboriginal peoples as a pivotal component of reconciliation.

abstract: Will try to get it published.

abstract: LL.M.


title: From Combat to Classroom: Canadian Soldiers in Transition

contributor:
Myers, Marie J.
Education

subject:
Adult Education
Canadian Soldiers
Cross-Cultural Transition
Transferable Skills
Transition Model
Veterans

abstract: Thesis (Master, Education) -- Queen's University, 2012-04-23 17:09:52.269

abstract:
The conflict in Afghanistan which has predominated much of the first decade of the new millennium has resulted in the creation of a new generation of Canadian war veterans. This veteran culture will include Canadian military personnel who were either directly or indirectly involved in active peacekeeping duty during their careers. Some of these men and women choose retirement to pursue other interests or second careers in the civilian world. Others are facing involuntary early retirement due to permanent medical or combat-related stress factors, such as post traumatic stress disorder (PTSD). Medical release, in combination with age and socioeconomic circumstances can result in adjustment difficulties (Sweet, Stoler, Kelter, & Thurrell, 1989; Westwood, Black & McLean, 2002).
	 A qualitative study of the experiences of ten Canadian soldiers in transition from military life to civilian education environments over a three-month period from November, 2011 to February, 2012 was carried out. The following themes emerged as major areas of discussion: transition issues, unanticipated transitions and non-events, camaraderie and the veteran identity, transferable skills, and support and resources. The transition model developed by Schlossberg and presented by Goodman, Schlossberg, and Anderson (2006) was used as a guiding theory to develop an understanding of the transition experience in reference to this new population of Canadian military veterans. Theories of cross-cultural transition were used as a framework for discussion. Recommendations for facilitating transition through education for Canadian soldiers are included.

abstract: M.Ed.


title: La récupération identitaire dans « Le ciel de Bay City » de Mavrikakis et « Le livre d’Emma » d’Agnant

contributor:
Inkel, Stéphane
French

subject: identité corps Shoah esclavagisme traumatisme filiation histoire

abstract: Thesis (Master, French) -- Queen's University, 2012-04-23 17:11:59.783

abstract: Ce mémoire explore l’identité fragmentée dont souffrent les héroïnes dans Le ciel de Bay City, de Catherine Mavrikakis, et dans Le livre d’Emma, de Marie-Célie Agnant et établit que cette fragmentation prend source dans un legs traumatique, soit la Shoah et l’esclavagisme transatlantique. Dans la famille ou la collectivité des héroïnes, et durant des générations, ces traumatismes ont été passés sous silence ou n’ont pas été intégrés au discours dominant. Par conséquent, l’histoire éclipsée hante le présent des protagonistes. Ce mémoire explore les différents bris dans la filiation symbolique. En tenant compte de théories féministes, postcoloniales et psychanalytiques, il s’intéresse aux façons dont les héroïnes composent avec ce passé inscrit dans l’horreur, entre autres à l’utilisation du corps ainsi qu’à la récupération de ce passé. Nous examinons l’utilisation du passé dans la reconstruction identitaire et déterminons si les héroïnes parviennent à surmonter les horreurs qu’elles ont découvertes. Nous estimons que malgré ce passé difficile, la découverte de celui-ci s’avère essentielle pour leur construction identitaire, car une fois que leur passé est recouvré, les protagonistes sont en mesure de le léguer à leur progéniture. Nous tenons compte du rôle de la transmission dans la réinsertion de leur filiation symbolique, car ce processus narratif produit une certaine catharsis : nous démontrons qu’en se racontant, les héroïnes parviennent à renouer leur filiation ascendante à leur descendance, se réinscrivant ainsi dans une logique historique. Finalement, nous mesurons l’impact mitigeant qu’exerce cette récupération identitaire sur la génération suivante.

abstract: M.A.


title: Students' Experiences and Teachers' Perceptions of Student Belonging in One Elementary School

contributor:
Berg, Derek
Education

subject:
Teachers' Perceptions
Belonging
Fitting In
Students' Experiences at School

abstract: Thesis (Master, Education) -- Queen's University, 2012-04-24 11:48:13.315

abstract: Belonging is a fundamental human need and this need is universal (Baumeister & Leary, 1995). How a student perceives their own belonging within a school and classroom can be predictive of their future engagement, motivation, achievement, and success of their interpersonal relationships. Students who feel connected are found to be less likely to engage in risky behaviours, be absent from school, or drop out of school entirely (Nichols, 2006; Anderman, 2003). Recent research on belonging has sought to examine the relationship between belonging and its outcomes on student behaviour (Anderman, 2003; Clegg, 2006; Goodenow, 1993; Ma, 2003; Osterman, 2000). There is an increasing need for belonging research to examine the development and incidence of belonging in children at school (Johnson, 2009; Osterman, 2000). This study has three research questions: a) What are students’ experiences with belonging in the school? b) What are teachers’ perceptions of students’ belonging in the school? c) How do the students’ experiences and teachers’ perceptions of student belonging in the school compare? The comparison of teachers’ and students’ responses will provide more information as to whether the students’ experiences and teachers’ perceptions of student belonging are aligned or if they are disparate. This data will make it possible to begin to target specific belonging factors in school programs and teacher practices.

abstract: M.Ed.


title: Transformative Effects of Learning & Assessment-Focused Educational Development

contributor:
Wilcox, Susan
Education

subject:
Educational Development
Assessment
Higher Education
Transformative Learning

abstract: Thesis (Ph.D, Education) -- Queen's University, 2012-04-25 00:00:54.215

abstract:
This heuristic inquiry outlines the chronology of my own theory-building, developing awareness and understanding of my educational development practice; I define my practice as learning&assessment-focused educational development. The inquiry maps the ways in which my early doctoral work shaped both my thinking and my practice as an educational developer eventually leading me to undertake a collaborative empirical study with the post-secondary teachers with whom I work. The purpose of the qualitative study we undertook together was to better understand how learning&assessment-focused educational development might facilitate transformative professional learning.
Sixteen college and university faculty members with whom I had engaged in learning&assessment-focused educational development, and who were familiar with the ICE (Ideas, Connections and Extensions) model of learning and assessment (Wilson, 1996; Fostaty Young & Wilson, 2000), collaborated with me as part of my heuristic inquiry. The study of our lived experience of learning&assessment-focused educational development became the next logical step of the investigation of practice that I had already begun to question and to write about. Together we set out to identify and name the instructional content, processes, approaches and relationships that supported significant professional learning. Findings indicated that the adoption of a framework, preferably one that is congruent with teachers’ emerging conceptions of teaching and learning, helps post-secondary teachers’ organize their thinking about learning and enables improved communication about their expectations for students’ learning. The
collaboration led to the identification of six essential characteristic features of learning&assessment-focused educational development.
Overall, this research contributes to the evidence-based literature on effective educational development practice and to the discussion on the scholarship of educational development research and on the scholarship of teaching in general.

abstract: PhD


title: Breaking the Cycle of Violence: an Exploration Into Dating Violence Prevention Curriculum

contributor:
Colgan, Lynda
Education

subject:
Prevention Programs
Dating Violence

abstract: Thesis (Master, Education) -- Queen's University, 2012-04-25 10:00:15.681

abstract:
In 2004 the Ontario Ministry of Education created the Safe Schools Action Team (SSAT) to advise on the development of a comprehensive approach to bullying prevention. When four years later in 2008 the SSAT re-engaged in order to review the issues of gender-based violence, homophobia, sexual harassment, and inappropriate sexual behaviour, recommendations were made for addressing these issues (Ministry of Education, 2008). One of the most significant dimensions of the SSAT report was their statement that the most effective method to learn about healthy relationships is through school curriculum (Ministry of Education, 2008). Taking the SSAT recommendation that the most effective method for educating adolescents on healthy relationships is through curriculum, the current study seeks to describe, from the teacher’s perspective, experiences with and motivations for using curriculum advocating healthy relationships, specifically dating violence prevention programming. The purpose of this thesis is to examine four female Ontario Physical and Health Education teachers’ personal and professional experience with teen dating violence and their knowledge about and use of dating violence prevention curriculum that has been approved by the Ontario Ministry of Education.
	The participants related their experiences with dating violence within their school communities and discussed how they approached these issues within their own classroom. The results of this study indicate that dating violence continues to be a prevalent issue for Ontario secondary schools, and there is a need for continued research into how to teach dating violence prevention in meaningful ways.

abstract: M.Ed.


title: Transient Droop Control Strategy for Parallel Operation of Distributed Energy Resources in an Islanded Microgrid

contributor:
Bakhshai, Alireza
Electrical and Computer Engineering

subject:
Droop
Control
Small Signal Stability
Microgrid

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-04-25 12:08:48.634

abstract:
Future electric grid will evolve from the current centralized and radial model toward a more distributed one. In recent years, distributed generation (DG) units have been playing an important role in electric generation due to their promising advantages in reducing air pollution, improving power system efficiency, and relieving stress on power transmission and delivery systems. Despite the increased penetration of DG systems, the application of individual DG system always has its limitation such as high cost/W, limited capacity and reliability, and safety concerns. A better way to utilize the emerging potential of DG is to take a system approach viewing generation and associated loads as a subsystem called a “microgrid”.
Forming an electric island, the microgrid can work autonomously following a disturbance. In the islanded microgrid, micro sources are responsible for maintaining the voltage and the frequency of the microgrid system within their speciﬁed limits and sharing the load between the generators in a stable manner. However, a robust and stable operation of a microgrid depends on a robust control scheme of the microgrid sources.
The most common technique to control microgrid sources is based on conventional droop characteristics. Although the conventional frequency/voltage droop technique properly shares a common active load, the reactive power sharing accuracy can be strongly affected by system parameter and active power control. In addition, frequency variations of different sources in transient mode can cause poor active power sharing.
To override the above-mentioned problems, a novel frequency/voltage droop scheme is proposed in this thesis. The proposed scheme improves the performance of the microgrid in terms of power sharing and voltage regulation and smooths the system’s dynamic and transient responses.
This work has developed the modeling, control parameters design, and power-sharing control starting from a single voltage source inverter to a number of interconnected DG units forming a flexible microgrid. Specifically, this thesis presents:
•	A control-oriented modeling based on active and reactive power analysis.
•	A control synthesis based on enhanced droop control technique.
•	A small signal stability study to give guidelines for properly adjusting the control system parameters according to the desired dynamic response.

abstract: I am going to publish a journal paper based on this thesis. So, I prefer not to publish it right now.

abstract: M.A.Sc.


title: A Clash of Two Imperatives: the Right to Know Versus the Need to Keep Secret in the Context of Criminal Law and National Security Matters

contributor:
Stuart, Don
Law

subject:
PII
Informants
Undertakings
Privilege
Disclosure
National Security
Public Interest Immunity

abstract: Thesis (Ph.D, Law) -- Queen's University, 2012-04-25 15:01:59.292

abstract:
More than ever before, two imperatives, ‘the right to know’ and ‘the need to keep secret’, find themselves in a contest for a position of primacy in the contemporary legal system. The need to keep secret is antipathetic to the right to know. The Canadian Charter of Human Rights and Freedoms has entrenched a person’s right to disclosure of both exculpatory and inculpatory material in possession of the prosecution. Moreover, the common law has placed the additional responsibility on the prosecution to inquire of third parties as to the existence and production of material relevant to the defence.  Despite the entrenchment of the right to disclosure the demands by the state have steadily grown for more evidence to be withheld from defendants, parties to proceedings and the public in general. The applications for in camera or ex parte hearings are common place and frequently acceded to.

This thesis seeks to examine the clash of the two imperatives from the Canadian perspective. By using a comparative analysis of other jurisdictions throughout the thesis, it examines the various legislative instruments and common law employed in the Canadian Courts in respect of ‘ordinary’ criminal trials as well as trials of suspected terrorists, specifically, in respect of disclosure and the ability to withhold material from other parties and refrain from the obligation to disclose. The thesis includes a full analysis of disclosure options, public interest immunity, informer privilege, special advocates and other regimes, and claims of privilege in the interests of national security.

The thesis provides a number of detailed recommendations as to how Canada can better balance rights of accused against the public  interest and the needs of those who enforce the law.. The recommendations call for legal reforms, some new institutions for better accountability and new internal standards for those engaged in the investigation of crimes and national security matters.

abstract: Third party interest. Examples given in thesis, which are my personal examples,remain part of an open investigation.

abstract: PhD


title: Modelling MSW Leachate Characteristics and Clogging

contributor:
Rowe, Kerry
Civil Engineering

subject:
Numerical Modelling
Landfills
Service Life
Design
Leachate Collection Systems
Clogging

abstract: Thesis (Ph.D, Civil Engineering) -- Queen's University, 2012-04-26 14:03:22.666

abstract: A numerical model (BioClog) is developed to examine changes in key municipal solid waste (MSW) leachate characteristics and the porosity of porous media (clogging) as the leachate passes through the drainage layer of a leachate collection system (LCS). The model considers multiple-species reactive leachate transport through porous media. It simulates biofilm growth and loss, deposition of suspended particles, and precipitation of minerals on the surface of porous media. It is used to examine the long-term performance of both the granular porous media and nonwoven geotextiles in LCSs. Modelling of laboratory mesocosm cells filled with gravel usually used in landfills and permeated by landfill leachate shows encouraging agreement between the observed and measured effluent chemical oxygen demand (COD) and calcium concentrations as well as the gravel porosity within the saturated drainage layers. Studies of early generation LCSs involving finger (French) drain systems show that the finger drains are not effective at controlling leachate mounding within the landfill and the calculated leachate mound thicknesses agree well with observed field data. A numerical examination of the recent generation of LCSs, comprised of the granular drainage blanket and perforated drainage pipes, shows that an increase in grain size increases the service life and that increasing the spacing between collection pipes (i.e., the drainage path) decreases the service life of LCSs. Filter-separator layers between the waste and granular drainage layers are shown to increase the service life of LCSs. The modelling results indicate that the calculated clog mass within the saturated drainage layer is dominated by the inorganic material and the calculated service life of LCSs is dependent on the leachate strength examined. Finally, a new practical model for estimating the service life of LCSs is developed and calibrated against the data from the BioClog model. The simplified model could be used by the practicing engineers for estimating the service life and optimizing the design of LCSs in MSW landfills.

abstract: PhD


title: The association between usual health care utilization and stage at diagnosis in laryngeal cancer

contributor:
Groome, Patti A.
Hall, Stephen F.
Community Health and Epidemiology

subject:
Stage at Diagnosis
Epidemiology
Health Care Utilization
Cancer
Health Services Research

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-04-26 10:50:05.976

abstract:
Background:  A significant number of laryngeal cancer patients are diagnosed with advanced-stage disease.  Since stage at diagnosis is an important prognostic factor, it is necessary to understand the characteristics of individuals at risk of being diagnosed at an advanced stage.
Objectives:  (1) Compare usual health care utilization between laryngeal cancer patients and the general population.  (2) Evaluate the association between usual health care utilization and stage at diagnosis in laryngeal cancer.
Methods:  The study population included 1,702 laryngeal cancer patients diagnosed from 2005–2008, and 8,510 matched-controls from the general population.  Demographic, clinical, and health administrative data from Ontario were used to measure usual health care utilization in a two-year period (i.e. frequency of encounters, continuity of care, primary care model enrolment, and preventive services use), stage at diagnosis, and covariates.
Results:  Laryngeal cancer patients had fewer health care encounters and a greater propensity for using preventive services than the general population.  Comparisons of usual health care utilization among laryngeal cancer patients showed significant trends across Stage I–IV for the frequency of encounters (p=0.002), continuity of care (p=0.02), and preventive services use (p<0.0001).  Stage I patients were less likely than Stage II–IV patients to have a low frequency of encounters (10%), low continuity of care (28%), and no preventive services use (28%).  In adjusted multivariable analyses, low continuity of care was marginally associated with an increased risk of advanced-stage laryngeal cancer (RR [95% CI]: 1.17 [1.01, 1.34]).  Stratification by subsite showed a marginally significant association between continuity of care and stage in glottic cancer (RR [95% CI]: 1.25 [0.98, 1.58]), but no association in supraglottic cancer (RR [95% CI]: 1.01 [0.89, 1.15]).
Conclusions:  Laryngeal cancer patients’ patterns of usual health care utilization differ from the general population.  There was little evidence of an effect of usual health care use on the risk of advanced-stage laryngeal cancer in multivariable analyses adjusting for confounders.  Multinomial regression may be needed to fully elucidate the effects of health care utilization across Stage I–IV.  Understanding health care utilization among laryngeal cancer patients is important for improving early detection and warrants further research.

abstract: M.Sc.


title: Effects of Initial Conditions on Turbulence Length Scale and Energy Distributions in the Near to Intermediate Field of a Round Free Jet

contributor:
Pollard, Andrew
Mechanical and Materials Engineering

subject:
Round Jet
Hot Wire
Initial Conditions
Flow Control

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2012-04-27 16:06:31.03

abstract:
This thesis examines the effects of spatial location, Reynolds number and near exit flow modification on the development region of a round, free, turbulent jet. It is based on the publications generated by the author. The experiments were carried out over the range of Reynolds numbers between 10000 < ReD < 50000, where ReD is calculated based on the jet exit mean velocity and the nozzle exit diameter. The measurements were performed in the near- to intermediate-field region of a free jet defined between 0 ≤ x/D ≤ 30. In order to control the flow near the exit, two wire rings, with square cross-sections, of sides h = 1.5 mm, and outer diameter Dwire = 71.6 mm (positioned in the shear layer and called Rsl) and Dwire = 60 mm (positioned in the potential core and called Rpc) were placed at a stand-off distance downstream of the jet nozzle exit plane x/D = 0.03. Both stationary and flying hot wires were used to investigate the jet flow field. The results showed a considerable reduction in the jet spread rate and turbulence intensity using the passive rings. The reduction in the velocity decay rate was more obvious in the case of Rsl in lower Re; however, it was observed that as Re increases, the velocity decay rate became nearly the same for both cases of Rsl and Rpc.
The axial velocity spectra showed the initial shear layer instability (shear layer mode) was suppressed while the jet preferred instability (preferred mode) remained active as the shear layer and potential core were modified. This shows the separation of these modes and is at variance with ideas that appeared in the literature that claimed the dependency of these two modes.

abstract: M.A.Sc.


title: Magnitude and controls of microbial nitrate production  in the streams and till of a glaciated alpine catchment,  Canadian Rocky Mountains, Alberta

contributor:
Lafrenière, Melissa J.
Geography

subject:
Nitrogen cycling
Biogeochemistry
Oxygen isotopes
Hydrochemistry
Canadian Rocky Mountains
Glacier ecosystems
Glacier forefield

abstract: Thesis (Master, Geography) -- Queen's University, 2012-04-26 14:47:17.29

abstract: In the summer of 2010, fieldwork was conducted in the Robertson Valley, Canadian Rocky Mountains, Alberta to assess the magnitude and controls of microbial nitrification in proglacial till and in supraglacial, subglacial, and proglacial streams.  Seasonal precipitation and glacial and proglacial runoff was sampled for hydrochemical and stable isotope analyses (δ18O and δ15N of nitrate [NO3-]).  Lower Ca:Mg ratios, higher mean Σmajor ions, and an increased importance of reactions with slower dissolution kinetics in subglacial streams and proglacial seeps indicated waters here experienced longer rock-water contact time than in dilute supraglacial streams.  Additionally, waters emanating from longer residence time flowpaths acquired substantial NO3- from nitrification reactions.  Using δ18O-NO3- in a simple end-member mixing model, the fraction of NO3- derived from microbial nitrification was estimated to be 44 to 56% in the two subglacial streams, and greater than 80% in proglacial seeps. These results show that atmospherically-derived nitrogen (N) in this glacial valley undergoes substantial biological cycling prior to export in surface runoff.  Water flowing from the east subglacial stream (RE) received a larger portion of its melt from a sediment-rich, slow drainage system and had a higher proportion of nitrified NO3- compared to the west subglacial stream (RW), where runoff was similar in composition to supraglacial runoff, indicating that the nature of subglacial flowpaths is an important factor in determining the amount of microbially-cycled nutrients that are exported from a glacier.  Sixteen 34-day in situ soil incubations revealed that net mineralization and net nitrification occurred at all four sampling sites in the glacier forefield along a 1.6 km chronosequence; however, there was no significant difference among these rates with time since deglaciation or temperature.  Instead, net mineralization and net nitrification rates were significantly correlated (p < 0.05, n = 16) with measured physical and chemical soil variables, including total organic carbon, total N, bulk density, pH, and clay content, suggesting that substrate availability is a larger control on N-cycling processes than time since deglaciation.  High variability in inorganic soil N pools and N-cycling rates indicates that there are likely hot spots of biogeochemical activity within glacial till.

abstract: M.Sc.


title: A Study of Traffic Locality and Reliability in  Peer-to-Peer Video Streaming Applications

contributor:
Hassanein, Hossam S.
Computing

subject:
peer-to-peer network
video streaming

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2012-04-26 15:20:35.555

abstract:
The past decade has witnessed tremendous growth of peer-to-peer (P2P) video
streaming applications on the Internet. For these applications, playback
smoothness and timeliness are the two most important aspects of users' viewing
experiences, whereas the amount of traffic is Internet service providers' main
concern. According to the playback delay, video streaming can be classified into
on-demand streaming, live streaming, and interactive streaming. P2P live
streaming applications typically have an arbitrary number of users, tens of
seconds of playback delay, and a high packet delivery rate, but their heavy
traffic incurs great financial expenditure and threatens the quality of other
services. Interactive streaming applications usually have a small group size,
several hundreds of milliseconds of playback delay, and reasonable traffic
volume, but cannot achieve a high packet delivery rate. The goal of this thesis
is to study traffic locality and reliable delivery of packets in large-scale
live streaming and small-scale interactive streaming applications, while keeping
the playback delay well below the targeted applications' limits.

For P2P live streaming applications, we first identify "typical" schemes from
existing P2P live streaming schemes, investigate packet propagation behavior and
the impact of neighboring strategies on system performance, and then propose
innovative schemes that take both users' viewing experience and traffic locality
into consideration. We show that the network-driven tree-based schemes with the
swarming technique as a re-transmission error-correction mechanism are superior
to the data-driven swarm-based or tree-based schemes, and a properly designed
tree-based scheme can localize the traffic while maintaining a high packet
delivery rate.

For interactive streaming applications, we analyze the efficacy of systematic
forward error-correction (FEC) codes against the bursty errors of Internet links
when using peers to provide multiple one-hop paths between two communication
parties.  We find that although using peers for path diversity often results in
a lower post-FEC packet loss ratio, some conditions do apply.  The interplay of
a number of factors, such as the Internet links' error ratio and burst length
and the coding parameters, determines the performance of FEC.  We provide
guidelines and computation methods to determine whether the use of peers for
path diversity can be justified.

abstract: PhD


title: Dyadic Green Functions and their applications in Classical and Quantum Nanophotonics

subject:
Quantum Optics
Nanophotonics

abstract: Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2012-04-26 15:25:53.178

abstract: Research in solid-state nanophotonics and quantum optics has been recently pushing the limits in semiconductor microcavity design. High quality microcavities that confine light into small volumes are now able to drastically alter the local density of states (LDOS). Plasmonic systems can provide smaller effective confinements, however it is unclear if the benefits of confinement are good enough to balance material losses due to non-radiative processes. This thesis presents a compendium of techniques for calculating photonic Green functions in various lossy, inhomogeneous magneto-dielectric systems. Subsequently we derive a rigorous theory of quantum light-matter interactions, valid in both weak and strong coupling limits, and show how the classical photonic Green function is developed to calculate Purcell factors, Lamb shifts, and the near and far field spectra from a single photon emitter. Using these techniques, this work investigates the classical and quantum optical properties of a variety of inhomogeneous structures, including their coupling to single photon emitters. This includes examining Purcell factors above negative index slabs and showing the convergence of many slow-light modes leads to a drastic increase in the LDOS along with large Lamb shifts. The optical trapping of metallic nanoparticles is examined above a negative index slab and a silver half-space, showing the importance of interparticle coupling on the optical forces. Then the interaction between a quantum dot and a metallic nanoparticle is studied where far-field strong coupling effects are observed only when the metallic nanoparticle is considered beyond the dipole approximation. Finally, this work addresses the issue of the LDOS diverging in lossy materials, which necessitates a description of spontaneous emission beyond the dipole approximation; the ``local field problem'' in quantum optics is revisited and generalized to include local field corrections for use in any photonic medium. The strength of finite-difference time-domain techniques is demonstrated in a number of cases for the calculation of regularized Green functions in lossy inhomogeneous media.  This thesis presents a comprehensive study of Green function approaches to model classical and quantum light-matter interactions in arbitrary nanophotonic structures, including quantum dots, semiconductor microcavities, negative index waveguides, metallic half-spaces and metallic nanoparticles.

abstract: PhD


title: The Rise of Nemausus from Augustus to Antoninus Pius: A Prosopographical Study of Nemausian Senators and Equestrians

contributor:
Kavanagh, Bernard J.
Classics

subject:
Nemausus
Nimes
Gallia Narbonensis
Roman History

abstract: Thesis (Master, Classics) -- Queen's University, 2012-04-26 16:30:58.26

abstract: Prosopography seeks to learn about social patterns and establish relationships within a well-defined group of individuals, which is accomplished by studying their biographies and analyzing the data within defined parametres.  The adlection of provincials into the equestrian and senatorial orders started during the late Republic and continued into the early Principate.  It integrated provincials into Rome’s social and political systems and provides the opportunity to closely examine how their roles evolved as time passed during the early Roman Empire.  This thesis will show that Nemausus, a provincial tribal settlement in Gallia Narbonensis, was one of the most important towns of the Roman Empire during the early Principate and achieved its prominence through sustained production of senators from Augustus to Marcus Aurelius and, in particular, through its prominent role during the dynasty of the Five Good Emperors.  The role of its equestrians and their inability to attain the highest offices of their order will be discussed.  Chapter Three will focus on Nemausus’ physical transformation as it was converted from a Celtic settlement into a Roman colony, and will lay the groundwork for its rise in the established social structures.  Chapter Four will provide a detailed examination of Nemausian equestrians, evaluate their careers individually and illustrate how indispensable they were to Nemausus’ growth even if they did not attain the highest offices within their order.  Chapter Five will focus on Nemausian senators much in the same manner as the previous chapter.  Unlike their equestrian counterparts, Nemausian senators attained great heights in Rome, becoming generals, consuls, and advisors to the emperor.   Eventually they became the Imperial family itself, placing the provincial town at the forefront of the Western Roman Empire.  Chapter Five will also propose to narrow the scope of Syme’s Hispano-Narbonensian nexus to include only the towns of Italica and Nemausus due to their influence during the dynasty of the Five Good Emperors.  A variety of evidence will be used throughout the discussion, in particular epigraphical and literary sources.  By examining the careers of Nemausian elites, their impact on the Roman Empire and their native town’s increased status, will be discovered.

abstract: M.A.


title: Assessing the responses of Cladocera to a failed exploratory hydrocarbon drilling-mud sump in the Mackenzie Delta uplands (Northwest Territories, Canada)

subject:
sump
Cladocera
Mackenzie Delta Uplands

abstract: Sumps act as the main form of containment and disposal method of wastes associated with exploratory hydrocarbon drilling. Leakage of drilling wastes from these sumps to the aquatic environment can be very damaging because of their toxic constituents. The purpose of the paleolimnological study is to investigate the long-term trends of a failed exploratory hydrocarbon drilling-mud sump on cladoceran assemblages. Failed sumps are expected to release drilling wastes that will increase lake water conductivity, salinity, and ionic composition. In an attempt to determine if past sump failures have affected aquatic biota, subfossil cladoceran remains were analyzed from the sediments of impacted Lake I20 and control Lake C23 in the Mackenzie Delta uplands (NT, Canada). Water was sampled to provide current water-chemistry data to compare between the two lakes. The results showed that conductivity, DOC, DIC, TDS, TSS, turbidity, and the levels of calcium, phosphorus, sodium, and sulphate in Lake I20 were still elevated compared to Lake C23. The cladocera assemblage in Lake I20 showed a distinct shift coincident with the timing of the construction and abandonment of sump Parsons F-09, suggesting that the sump might have never been successful at containing the drilling wastes. It is possible that the drilling wastes were already affecting the aquatic environment of Lake I20 at the time of sump excavation based on the stratrigraphic profile. The sedimentary record of Lake C23 showed no abrupt changes. Instead, the assemblage showed changes suggestive of climate change rather than sump disturbance. This paleolimnological study provides a better understanding of the impacts of sump activity in the Arctic aquatic ecosystems and provides initial long-term records of sump disturbance.


title: Magnetic fields and the variable wind of the early-type supergiant β Ori

subject:
stellar winds
Stars (magnetic)
stars (early type)
stars (supergiant)
spectropolarimetry

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2012-04-29 02:10:41.308

abstract:
Supergiant stars of spectral types B and A are characterized by variable and structured winds, as revealed by variability of optical and ultraviolet spectral lines. Non-
radial pulsations and magnetically supported loops have been proposed as explanations for these phenomena. The latter hypothesis is tested using a time series of 65
high-resolution (λ/∆λ ∼ 65, 000) circular polarization (Stokes I and V ) spectra of
the late B type supergiant Rigel (β Ori, B8 Iae), obtained with the instruments ESPaDOnS and Narval at the Canada-France-Hawaii Telescope and the Bernard Lyot Telescope, respectively. Examination of the unpolarized (Stokes I) spectra using standard spectral analysis tools confirms complex line profile variability during the 5 month period of observations; the high spectral resolution allows the identification of a weak, transient Hα feature similar in behaviour to a High Velocity Absorption event. Analysis of the Stokes V spectra using the cross-correlation technique Least Squares Deconvolution (LSD) yields no evidence of a magnetic field in either LSD Stokes V profiles or longitudinal field measurements, with longitudinal field 1σ error bars of ∼ 12 G for individual observations, and a mean field in the best observed period of 3 ± 2 G. Synthetic LSD profiles fit to the observations using a Monte Carlo approach yield an upper limit on the surface dipolar field strength of Bdip ≤ 50 G for most orientations of the rotational and magnetic axes, lowered to Bdip ≤ 35 G if the mean LSD profile from the most densely time-sampled epoch (with an LSD SNR of ∼80,000) is used. A simple two-spot geometry representing the footpoints of a magnetic loop emerging from the photosphere yields upper limits on the spot magnetic fields of 60–600 G, depending on the filling factor of the spots. Given existing measurements of the mass loss rate and the wind terminal velocity, these results
cannot rule out a magnetically confined wind as, for Bdip ≤ 15 G, η∗ ≥ 1. However, the detailed pattern of line profile variability seems inconsistent with the periodic wind modulation characteristic of known magnetic early-type stars, suggesting that magnetic fields do not play a dominant role in Rigel’s variable winds.

abstract: M.Sc.


title: Phylogeography of Brown and Red-Footed Boobies: a Complex History of Isolation and Gene Flow

contributor:
Friesen, Vicki L.
Biology

subject:
Speciation
Population Differentiation
Secondary Contact
Evolution
Molecular Ecology
Habitat Preference
Seabirds

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2012-04-28 17:28:53.302

abstract:
Speciation is an important process that is responsible for the generation of biodiversity on Earth. The importance of gene flow during speciation is hotly debated; however, it can be investigated by studying the process of intraspecific population differentiation. Here, I investigate the mechanisms that influence population differentiation and gene flow in brown (Sula leucogaster) and red-footed boobies (S. sula). These species are congeneric, broadly sympatric, and ecologically similar; however, they differ in their marine habitat preference (inshore vs. pelagic). I hypothesized that: (i) gene flow is restricted by major physical barriers in both species, and (ii) gene flow in the absence of physical barriers is more prevalent in red-footed boobies due to their pelagic marine habitat preference.
	First, I characterized the structure and function of the booby mitochondrial genome. Using extensive DNA sequencing and phylogenetic methods, I found that boobies have tandemly duplicated mitochondrial control regions that evolve in concert. I suggest that concerted evolution of duplicated control region may be common in seabirds.
	To quantify matrilineal population genetic structure and gene flow, I sequenced one control region in 513 brown and red-footed boobies. Both species exhibited strong population genetic structure that was attributable to continental barriers to gene flow such as the Isthmus of Panama. In the absence of physical barriers, gene flow was more prevalent in red-footed boobies. I also used microsatellite and nuclear intron loci to perform multilocus phylogeographic analyses of brown and red-footed boobies. Individuals of both species could be grouped into four genetic populations that corresponded to oceanographic regions. In red-footed boobies, gene flow following secondary contact of previously isolated lineages was common, perhaps due to a pelagic habitat preference. In brown boobies, major genetic populations apparently diverged in the absence of gene flow. Despite this, Isla San Benedicto in the Eastern Pacific is a site of secondary contact between brown booby lineages that diverged approximately one million years ago, and hybrids are apparently fertile. These findings suggest that gene flow following secondary contact may be an important, but overlooked, component of speciation.

abstract: PhD


title: "Terribile Disegno" and "Eroico Componimento" : Mattia Preti's Artistic Practices and their Reception in Seventeenth- and Eighteenth-Century Italy

contributor:
Schütze, Sebastian
Art History

subject:
Mattia Preti (1613-99)
Painting, Italian, Baroque

abstract: Thesis (Ph.D, Art History) -- Queen's University, 2012-04-29 18:26:13.056

abstract: The following study examines the artistic strategies of the Italian Baroque painter Mattia Preti (1613-99) in conjunction with their early reception in seventeenth- and eighteenth-century Italy. In addition to studying the first descriptions of the painter's art and his early biographers' characterization of his style, Bernardo De Dominici's comprehensive "Vita del Cavalier Fra' Mattia Preti" is analyzed in order to establish Preti's place in the history of Neapolitan Baroque painting. In so doing, descriptions of the painter's art are compared and contrasted with those of his contemporaries. Following the investigation of the early sources and biographies, the painter's strategies are studied through selected paintings executed between circa 1650 and 1680. These include such works as the Aquila 'Martyrdom of St. Bartholomew', the London 'Wedding at Cana', the Naples 'Feast of Absalom', and the Siena 'Canonization of St. Catherine'. The case studies highlight a number of practices the artist used to distinguish himself from his peers. In sum, this study argues that the early biographical accounts, while only partially conveying the breadth of the painter's art, function as a point of departure for accessing and comprehensively examining his representational strategies. Ultimately, this dissertation demonstrates that Preti was an artist who actively and continuously experimented with a range of pictorial possibilities.

abstract: PhD


title: Stochastic Dynamic Optimization of Cut-off Grade in Open Pit Mines

contributor:
Martin, Jim
Mining Engineering

subject:
Real Options
Mine planning
Economics
Mine design
Mine evaluation
Cut-off
Hedging
Simulation
Finance
Mine optimization
Valuation
Mining
Optimization
Stochastic
Cut-off grade

abstract: Thesis (Master, Mining Engineering) -- Queen's University, 2012-04-30 22:36:51.257

abstract:
Mining operations exploit mineral deposits, processing a portion of the extracted material to produce salable products. The concentration of valuable commodities within these deposits, or the grade, is heterogeneous. Not all material has sufficiently high grades to economically justify processing. Cut-off grade is the lowest grade at which material is considered ore and is processed to create a concentrated commodity product. The choice of cut-off grade at a mining project can be varied over time and dramatically impacts both the operation of the mine and the economics of the project.
The majority of literature and the accepted industry practices focus on optimizing cut-off grade under known commodity prices. However, most mining operations sell their products into highly competitive global markets, which exhibit volatile commodity prices. Making planning decisions assuming that a given commodity price prediction is accurate can lead to sub-optimal cut-off grade strategies and inaccurate valuations. Some academic investigations have been conducted to optimize cut-off grade under stochastic or uncertain price conditions. These works made large simplifications in order to facilitate the computation of a solution. These simplifications mean that detailed mine planning data cannot be used and the complexities involved in many real world projects cannot be considered.
A new method for optimizing cut-off grade under stochastic or uncertain prices is outlined and demonstrated. The model presented makes use of theory from the field of Real Options and is designed to incorporate real mine planning data. The model introduces two key innovations. The first is the method in which it handles the cut-off grade determination. The second innovation is the use of a stochastic price model of the entire futures curve and not simply a stocastic spot price model. The model is applied to two cases. The first uses public data from a National Instrument 43-101 report. The second case uses highly detailed, confidential data, provided by a mining company from one of their operating mines.

abstract: M.A.Sc.


title: A Passive or Active Biogenic Origin of the Whitings Phenomenon by Synechococcus bacillaris

subject:
whitings
calcium carbonate precipitation

abstract:
Whitings are a natural phenomenon of calcium carbonate (CaCO3) precipitation that occurs in both fresh and tropical marine waters. Previous studies have associated whitings with Synechococcus bacillaris and have suggested that these bacteria have an active role in whitings development including acting as nucleation sites and actively alkalinizing the surrounding microenvironment. CaCO3 minerals that have been influenced by bacteria in their formation have been found to have different crystal structures than inorganically precipitated CaCO3. What is unknown is whether the carbonate (CO32-) that is incorporated into the whitings comes from the external environment or is produced by the bacteria through photosynthesis.
      Oligotrophic S. bacillaris was grown in the laboratory in L1 medium. Microcosm experiments were conducted under closed conditions. pH in the experimental microcosms rose to 9.5 resulting in the precipitation of CaCO3, but then re-acidified as the bacteria entered death phase resulting in the precipitate re-dissolving. Uncontrolled temperature shocks caused decreased cell counts, clumping and acidification.
      Inorganic CaCO3, experimental precipitate, and pure cells were examined under scanning electron microscopy (SEM) and electron dispersive x-ray spectrometry (EDS). The inorganic CaCO3 had crystalline structures consistent with previous studies (mostly aragonite and amorphous calcium carbonate[ACC]). Extracellular polysaccharide (EPS) was observed in the experimental precipitate, but no CaCO3 precipitates were found, and no bacteria or CaCO3 could be observed in the pure cell sample. Improvements that could be made include stable isotope analysis, more stringent temperature control, variation of conditions and the use of ESEM or gold-coating SEM.


title: Empirical Studies of Performance Bugs and Performance Analysis Approaches for Software Systems

contributor:
Hassan, Ahmed E.
Computing

subject:
Software Performance
Performance Bugs
Empirical Software Engineering
Computer Science
User-centric performance analysis

abstract: Thesis (Master, Computing) -- Queen's University, 2012-04-30 01:28:22.623

abstract:
Developing high quality software is of eminent importance to keep the existing customers satisfied and to remain competitive. One of the most important software quality characteristics is performance, which defines how fast and/or efficiently a software can perform its operation.

While several studies have shown that field problems are often due to performance issues instead of feature bugs, prior research typically treats all bugs as similar when studying various aspects of software quality (e.g., predicting the time to fix a bug) or focused on other types of bug (e.g., security bugs). There is little work that studies performance bugs.

In this thesis, we perform an empirical study to quantitatively and qualitatively examine performance bugs in the Mozilla Firefox and Google Chrome web browser projects in order to find out if performance bugs are really different from other bugs in practice and to understand the rationale behind those differences.

In our quantitative study, we find that performance bugs of the Firefox project take longer time to fix, are fixed by more experienced developers, and require changes to more lines of code. We also study performance bugs relative to security bugs, since security bugs have been extensively studied separately in the past. We find that security bugs are re-opened and tossed more often, are fixed and triaged faster, are fixed by more experienced developers, and are assigned more number of developers in the Firefox project. Google Chrome project also shows different quantitative characteristics between performance and non-performance bugs and from the Firefox project.

Based on our quantitative results, we look at that data from a qualitative point of view. As one of our most interesting observation, we find that end-users are often frustrated with performance problems and often threaten to switch to competing software products.

To better understand, the rationale for some users being very frustrated (even threatening to switch product) even though most systems are well tested, we performed an additional study. In this final study, we explore a global perspective vs a user centric perspective of analyzing performance data. We find that a user-centric perspective might lead to a small number of users with considerably poor performance while the global perspective might show good or same performance across releases.

The results of our studies show that performance bugs are different and should be studied separately in large scale software systems to improve the quality assurance processes related to software performance.

abstract: M.Sc.


title: Using Topic Models to Support Software Maintenance

contributor:
Skillicorn, B. David
Cordy, James R.
Computing

subject:
latent topic models
software engineering

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2012-04-30 18:16:04.05

abstract:
Latent topic models are statistical structures in which a "latent topic" describes some relationship between parts of the data.  Co-maintenance is defined as an observable property of software systems under source control in which source code fragments are modified together in some time frame.  When topic models are applied to software systems, latent topics emerge from code fragments.  However, it is not yet known what these latent topics mean.

In this research, we analyse software maintenance history, and show that latent topics often correspond to code fragments that are maintained together.  Moreover, we show that latent topic models can identify such co-maintenance relationships even with no supervision.  We can use this correlation both to categorize and understand maintenance history, and to predict future co-maintenance in practice.  The relationship between co-maintenance and topics is directly analysed within changelists, with respect to both local pairwise code fragment similarity and global system-wide fragment similarity.  This analysis is used to evaluate topic models used with a domain-specific programming language for web service similarity detection, and to estimate appropriate topic counts for modelling source code.

abstract: PhD


title: Sociospace: A Smart Social Framework Based on the IP Multimedia Subsystem

subject:
smart spaces
social networks

abstract: Thesis (Ph.D, Computing) -- Queen's University, 2012-04-30 11:14:29.054

abstract: Advances in smart technologies, wireless networking, and increased interest in contextual services have led to the emergence of ubiquitous and pervasive computing as one of the most promising areas of computing in recent years.  Smart Spaces, in particular, have gained significant interest within the research community. Currently, most Smart Spaces rely on physical components, such as sensors, to acquire information about the real-world environment. Although current sensor networks can acquire some useful contextual information from the physical environment, their information resources are often limited, and the data acquired is often unreliable.  We argue that by introducing social network information into such systems, smarter and more adaptive spaces can be created. Social networks have recently become extremely popular, and are now an integral part of millions of people’s daily lives. Through social networks, users create profiles, build relationships, and join groups, forming intermingled sets and communities. Social Networks contain a wealth of information, which, if exploited properly, can lead to a whole new level of smart contextual services. A mechanism is therefore needed to extract data from heterogeneous social networks, to link profiles across different networks, and to aggregate the data obtained. We therefore propose the design and implementation of a Smart Spaces framework that utilizes the social context. In order to manage services and sessions, we integrate our system with the IP Multimedia Subsystem. Our system, which we call SocioSpace, includes full design and implementation of all components, including the central server, the location management system, the social network interfacing system, the service delivery platform, and user agents. We have built a prototype for proof of concept and carried out exhaustive performance analysis; the results show that SocioSpace is scalable, extensible, and fault-tolerant. It is capable of creating Smart Spaces that can truly deliver adaptive services that enhance the users’ overall experience, increase their satisfaction, and make the surroundings more beneficial and interesting to them.

abstract: PhD


title: Bifurcations of Periodic Solutions of Functional Differential Equations with Spatio-Temporal Symmetries

contributor:
Offin, Daniel
Buono, Pietro-Luciano
Mathematics and Statistics

subject:
Functional Differential Equations
Bifurcations
Centre Manifold Reduction
Lang-Kobayashi Equations
Delay Equations
Semiconductor Lasers
Periodic Solutions

abstract: Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2012-04-30 11:25:01.011

abstract:
We study bifurcations of periodic solutions with spatio-temporal symmetries of functional differential equations (FDEs). The two main results are: (1) a centre manifold reduction around a periodic solution of FDEs with spatio-temporal symmetries, and (2) symmetry-breaking bifurcations for symmetric rings of delay-coupled lasers.

For the case of ODEs, symmetry-breaking bifurcations from periodic solutions has already been studied. We extend this result to the case of symmetric FDEs using a Centre Manifold Theorem for symmetric FDEs which reduces FDEs into ODEs on an integral manifold around a periodic solution. We show that the integral manifold is invariant under the spatio-temporal symmetries which guarantees that the symmetry structure of the system of FDEs is preserved by this reduction.

We also consider a problem in rings of delay-coupled lasers modeled using the Lang-Kobayashi rate equations. We classify the symmetry of bifurcating branches of solutions from steady-state and Hopf bifurcations that occur in 3-laser systems. This involves finding isotropy subgroups of the symmetry group of the system, and then using the Equivariant Branching Lemma and the Equivariant Hopf Theorem. We then utilize this result to find the bifurcating branches of solutions in DDE-Biftool. Symmetry often causes eigenvalues to have multiplicity, and in some cases, this could lead DDE-Biftool to incorrectly predict the bifurcation points. We address this issue by developing a method of finding bifurcation points which can be used for the general case of n-laser systems with unidirectional and bidirectional coupling.

abstract: PhD


title: CrowdNav:Information Dissemination System for Traffic Enhancement

subject:
traffic, smartphones
information dissemination

abstract: Thesis (Master, Computing) -- Queen's University, 2012-04-30 14:49:14.933

abstract:
In this work we present a traffic information dissemination system that seeks to
deliver relevant traffic information to drivers to help make their driving experience
more efficient, pleasant and safe. The system uses the crowd of drivers as the main
source of information. The crowd reports information about traffic either directly to
our system’s central server or to social networks. In case the information is reported
to a social network our system architecture allows the integration of social networks as
a traffic information source. It also allows the integration of other traffic information
sources such as local traffic monitoring agencies. Our system aggregates all traffic
information and delivers it to drivers subscribed to the system when they demand
it. In addition, our system provides an efficient navigation service that it takes
into account the current traffic conditions when planning a route. Furthermore, it
periodically checks if there are new traffic events that appear on the user’s current
route in which case the system will automatically give the user an alternate route.
We implement a prototype of our system that use the social networks as a traffic
information source and through the prototype evaluation we show that the prototype
of our system indeed delivers relevant traffic information to drivers and performs
intelligent navigation.

abstract: M.Sc.


title: Digital Control of Phase Staggered Multiple ZVS Inverters for Grid-connected Photovoltaic Systems

contributor:
Jain, Praveen K.
Electrical and Computer Engineering

subject:
Photovoltaic Systems
Microinverters
Renewable Energy
Soft Switching

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-04-30 15:06:26.071

abstract:
The grid connected PV plants comprising of the PV cells and the power electronic inverters are a widely used technology in distributed power generation systems based on renewable energy sources. Microinverters form an extensive part of the ongoing research in this field. This thesis focuses on the inverter section of the microinverter.  The cost and efficiency of the grid connected inverter is a chief contributing factor in the overall system price.

The MOSFETs used in the DC/AC inverter are usually hard switched causing a lot of EMI noise and losses in the inverter. This is true for both, single and three phase inverters. A low switching frequency is desirable to increase the efficiency, which in turn imposes a large compromise in designing the output filter. In this thesis, switching losses have been minimized by incorporating zero voltage switching at switch turn on and variable dead-time control at switch turn off. The soft switching technique is based on control algorithms and involves no use of any auxiliary circuit. Also, the size of the output filter is reduced without increasing the switching frequency, by employing multiple paralleled inverters. The interleaving technique that is usually used in dc/dc converters is extended for dc/ac inverters and is well employed to maintain the quality of the current fed into the utility grid. In this way, at low switching frequency, high efficiency and reduced cost and sizes are achieved.

The study is validated through simulation and lab experiments. The novel control circuit was first implemented using analog circuitry. After assessing the performance of the analog version of the proposed controller, it was then digitally implemented through the Field Programmable Gate Array (FPGA) technique.

abstract: For obtaining a patent from the research work presented in the thesis.

abstract: M.A.Sc.


title: Viability of Powerline Communication for Smart Grid Realization

contributor:
Hassanein, Hossam S.
Takahara, Glen
Electrical and Computer Engineering

subject:
Powerline Communication
Smart Grid

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2012-04-30 15:31:43.471

abstract: There is an international effort to develop smart grids to overcome the problems caused by aging power grids. However, to immigrate to the new grid, the IT infrastructure has to be integrated with the current power grid. There is currently an ongoing debate surrounding what would be the best choice for smart grid communication technology. One of the promising communication technologies for smart grid realization is powerline communication (PLC). PLC provides utilities the opportunity of managing their own network infrastructure. Power cables are everywhere; even rural areas are covered with power cables. However, because of its noisy environment and the low capacity of narrowband powerline communication (NBPLC), its viability for smart grid realization is being questioned. To investigate this issue, smart grid communication network requirements and powerline communication technologies and channel models are studied. Then, using MATLAB and Network Simulator-2, powerline communication and a smart grid communication network (SGCN) are simulated. The performance of different powerline channels for smart grid realization is investigated and a viable PLC infrastructure for smart grid communication network is proposed. Furthermore, to have a better understanding of the viability of powerline communication for the smart grid, some future smart grid advanced applications are investigated and integrated to the system. It is shown that although two types of powerline channels do not perform well, the proposed powerline communication infrastructure, even under advanced traffic, is capable of providing the smart grid with its communication prerequisites.

abstract: M.A.Sc.


title: Atom Transfer Radical Polymerization with Low Catalyst Concentration in Continuous Processes

contributor:
Cunningham, Michael F.
Hutchinson, Robin A.
Chemical Engineering

subject:
ATRP
Process Scale Up
Controlled Radical Polymerization

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-04-30 16:01:28.916

abstract:
Atom transfer radical polymerization (ATRP) is a dynamic technique that possesses tremendous potential for the synthesis of novel polymeric materials not possible through conventional free radical polymerization. However, its use on an industrial scale has been limited by the high level of transition metal complex required. Significant advances have been made in the last 5 years towards lowering the level of copper complexes used in ATRP, resulting in novel variants called “activator regenerated by electron transfer” (ARGET) and “single electron transfer-living radical polymerization” (SET-LRP).
To fully realize the potential of ATRP, its use in industrially relevant processes must be studied. Continuous processes such as tubular flow reactors and stirred tank reactors (CSTR) can reduce waste, improve productivity and facilitate process scale-up when compared to common batch reactors. The combination of low copper concentration ATRP techniques and continuous processes are especially attractive towards the design of a commercially viable process. This thesis presents a study into ARGET ATRP and SET-LRP as applied to continuous tubular and stirred tank reactors for the production of acrylic and methacrylic polymers.
The equilibrium which governs polymerization rate and control over molecular architecture is studied through batch ARGET ATRP experiments. The improved understanding of ARGET ATRP enabled the reduction of ligand from a 3 to 10 fold excess used previously down to a stoichiometric ratio to copper salts. ARGET ATRP was then adapted to a continuous tubular reactor, as well as to a semi-automated CSTR. The design of the reactors and the effect of reaction conditions such as reducing agent concentration and residence time are discussed.
The use of common elemental copper(0) such as copper wire and copper tubing is also investigated with SET-LRP for room temperature polymerization of methyl acrylate. SET-LRP is adapted to a CSTR to observe the effects of residence time on reaction rate, molecular weight control as well as copper consumption rate. The use of copper tubing as a catalyst source for SET-LRP is demonstrated and the design of a continuous tubular reactor using a combination of copper and stainless steel tubing is discussed.

abstract: PhD


title: Scale-Up of Latex Reactors and Coagulators: A Combined CFD-PBE Approach

contributor:
Cunningham, Michael F.
McKenna, Timothy F. L.
Chemical Engineering

subject:
Scale Up
Emulsion Polymerization
Polymerization
Polymer latex reactor
Coagulation
Latex

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-05-01 07:09:08.362

abstract:
The successful production of a wide range of polymer latex products relies on the ability to control the rates of particle nucleation, growth and coagulation in order to maintain control over the particle size distribution (PSD). The development of advanced population balance models (PBMs) has simplified this task at the laboratory scale, but commercialization remains challenging as it is difficult to maintain control over the composition (i.e. spatial distributions of reactant concentration) of larger reactors.

The objective of this thesis is to develop and test a combined Computational Fluid Dynamics (CFD) -PBM hybrid modeling framework. This hybrid modeling framework can be used to study the impact of changes in process scale on product quality, as measured by the PSD. The modeling framework developed herein differs from previously-published frameworks in that it uses information computed from species tracking simulations to divide the reactor into a series of interconnected zones, thereby ensuring the reactor is zoned based on a mixing metric. Subsequently, an emulsion polymerization model is solved on this relatively course grid in order to determine the time evolution of the PSD. Examination of shear rate profiles generated using CFD simulation (at varying reactor scales) suggests that, dependent on conditions, mechanically-induced coagulation cannot be neglected at either the laboratory or the commercial scale. However, the coagulation models that are formulated to measure the contributions of both types of coagulation simultaneously are either computationally expensive or inaccurate. For this reason the decision was made to utilize a DLVO-coagulation model in the framework. The second part of the thesis focused on modeling the controlled coagulation of high solids content latexes. POLY3D, a CFD code designed to model the flow of non-Newtonian fluids, was modified to communicate directly with a multi-compartment PBM. The hybrid framework was shown to be well-suited for modeling the controlled coagulation of high solid content latexes in the laminar regime. It was found that changing the size of the reactor affected the latex PSD obtained at the end of the process.  In the third part of the thesis, the framework was adapted to work with Fluent, a commercial CFD code, in order to investigate the scale-up of a styrene emulsion polymerization reaction under isothermal conditions. The simulation results indicated that the ability to maintain good control of the PSD was inversely related to the reactor blend time. While the framework must be adapted further in order to model a wider range of polymerization processes, the value of the framework, in obtaining information that would otherwise be unavailable, was demonstrated.

abstract: PhD


title: Timing and Mechanism of Sepsis-Induced Delayed Gastric Emptying in a Novel Mouse Model

contributor:
Vanner, Stephen
Paterson, William G.
Biology

subject:
gastric emptying
sepsis

abstract: Thesis (Ph.D, Biology) -- Queen's University, 2012-05-02 16:17:55.564

abstract:
Sepsis-induced delayed gastric emptying is a significant clinical problem for patients in intensive care units worldwide. A series of studies were carried out to examine the nature and mechanisms of sepsis-induced delayed gastric emptying using a novel mouse model which used a standard food source
and was devoid of upper gastrointestinal tract trauma and restraint.  Using this model, lipopolysaccharide (LPS) injection produced a dose-dependent decrease in
gastric emptying which onset by one hour. LPS produced an alteration in mouse behavior and piloerection at 30 minutes, increased resting respiratory rate at 3 hours, and did not impact body temperature. The onset of sepsis-induced delayed gastric emptying was closer to those centrally-mediated
clinical signs of sepsis (altered behavior and piloerection) than to the peripherally-mediated clinical signs (respiratory rate) suggesting a central mechanism. C-Fos activation of the area postrema (AP), the nucleus of the solitary tract (NTS), and the dorsal motor nucleus of the vagus (DMV) was examined 30 minutes after LPS injection which is the onset time for sepsis-induced delayed gastric emptying. LPS exposure produced significantly more activated
neurons in the AP and NTS, and less in the DMV. These results may suggest a central mechanism with the AP and NTS inhibiting the DMV. Examination of isolated strips of gastric antrum in a tissue bath showed a decreased contractile response to electrical field stimulation and carbachol after injection of LPS. This occurred at 18 hours
post LPS injection, but not at 6 hours. Using the mouse model, sepsis-induced delayed gastric emptying was shown to be occurring at 6 hours when no difference in contractility was measurable suggesting
intrinsic changes are not the cause.
These studies suggest a new mechanistic paradigm for sepsis-induced delayed gastric emptying in which there is a biphasic response. This involves an initial rapid, centrally-mediated delay in gastric emptying occurring the first hour and followed by an intrinsic tissue-level response several hours later characterized by a decrease in gastric muscle contractility.

abstract: PhD