contributor:
Leduc, Ryan J.
Ricker, S. L.
Computing and Software

subject:
Discrete-event systems (DES)
Supervisory control of DES
Decentralized control
State-space explosion problem

abstract:
In decentralized control, agents have only
a partial view and partial control of the system and must cooperate to
achieve the control objective. In order to synthesize a decentralized control
solution, a specification must satisfy the co-observability
property. Existing co-observability verification methods require the
possibly intractable construction of the complete system. To address
this issue, we introduce an incremental verification of
co-observability  approach. Selected subgroups of the system are evaluated
individually, until verification is complete. The new method is
potentially much more efficient than the monolithic approaches, in
particular for systems composed of many subsystems, allowing for some
intractable problems to be manageable.  Properties of this new strategy
are presented, along with a corresponding algorithm and an example.

To further increase the scalability of decentralized control, we wish
to adapt the existing Hierarchical Interface-Based Supervisory Control
(HISC) to support it. We introduce the Hierarchical
Interface-Based Decentralized Supervisory Control (HIDSC) framework
that extends HISC to decentralized control.
To adapt co-observability for HIDSC, we propose a per-component definition
of co-observability along with a verification strategy that requires
only a single component at a time in order to verify
co-observability. Finally, we provide and prove
the necessary and sufficient conditions for supervisory control
existence  in the HIDSC framework and illustrate our approach with an
example. As the entire system model never needs to be constructed, HIDSC
 potentially provides significant savings.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Assessing Heritage, Tradition, and Identity：Anthropological Research among the Jurchen People of Wanyan Village.

contributor:
Rethmann, Petra
Anthropology

abstract:
This dissertation traces the Chinese governmental project, Chinese Ethnics Identification Pro-ject (CEIP), of classifying the minorities’ social identity into a binary. Nevertheless, the CCP (Chinese Communist Party) government hated to admit this binary expression since it left a delusion to stress a horizontal equality among the ethnic minorities of equality status in Chi-nese policy. My research is also pertinent to investigating nation-state monopolies of legality and practices across the world as disenfranchised minorities argue for equal rights, privileges, and self-representation.
Between 2011-2014 I conducted five visits and covered 15 months of fieldwork in the village of Wanyan, Jingchuan County, Lanzhou City and Gansu Province. I conducted in-depth in-terviews with villagers and observed their daily life during my stay with several households. In order to assess the identity, heritage and tradition among the Jurchen people in Wanyan village, the historical past and present of these Jurchen will be thoroughly analyzed to con-struct memory and further assess the identity these people are still fighting for.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: THE FEASIBILITY OF USING X-RAY FLUORESCENCE ANALYSIS OF IRON, COPPER, AND ZINC IN THE CENTRAL NERVOUS SYSTEM IN A RODENT MODEL OF DYSMYELINATION

contributor:
Farquharson, Michael
Bock, Nicholas
Medical Physics

abstract: Trace elements are involved in many biological processes and serve important functions to maintain the normal development of the central nervous system (CNS). In the CNS, iron (Fe), copper (Cu), and zinc (Zn) are some of the most important elements that play critical roles as catalysts, cofactors, and structural components for many cellular enzymes and proteins. The deficiency or excess of these metals may lead to various neurological disorders. Demyelination is a condition of loss of myelin and leads to neurological diseases like Multiple Sclerosis. Myelin consists of transition metals and hence it would be interesting to study concentrations of these elements in normal and demyelinated models. X-Ray Fluorescence (XRF) is a popular non-destructive technique applied in trace element studies. The principle involves exciting a sample and detecting characteristic X-rays, which provide information on elemental concentrations in the sample. In the present studies the feasibility of XRF for trace element studies was explored. A total of 120 samples of brain and spinal cord tissues were collected from Long Evans (control) and Long Evans Shaker (dysmyelinated)–an incomplete formation of myelin sheaths–rats at ages of 3 weeks and 16 weeks. The samples were excited using x-rays from an Energy Dispersive X-Ray Diffraction (EDXRF) set-up. The spectral data was collected using an Silicon Drift Detector (SDD) and the resultant data were analysed to see if statistically significant changes in concentrations were present in the samples. The results were discussed and suggestions for future work were made.

abstract: Thesis

abstract: Master of Science (MSc)


title: Design of Energy-Efficient Uniquely Factorable Constellations for MIMO and Relay Systems

contributor:
Zhang, Jian-Kang
Electrical and Computer Engineering

subject:
MIMO Systems
Relay Systems
Noncoherent Communication
Uniquely factorable constellation
Signal Constellation Design

abstract: This thesis focuses on the concept of uniquely factorable constellations (UFCs) in the design of space-time block codes (STBCs) for wireless communication systems using three different approaches. Based on intelligent constellation collaboration, UFCs can provide the systematic design of a full diversity code with improved coding gain. Firstly, motivated by the energy-efficient hexagonal lattice carved from the Eisenstein integer domain, hexagonal UFCs and hexagonal uniquely factorable constellation pairs (UFCPs), of various sizes, are constructed for a noncoherent single-input multiple-output (SIMO) system.  It is proved that these designs assure the blind unique identification of channel coefficients and transmitted signals in a noise-free case and full diversity for the noncoherent maximum likelihood (ML) receiver in a noisy case. In addition, an optimal energy scale is found to maximize the coding gain. Secondly, using a matrix similar to the Alamouti matrix and the UFCP concept based on the quadrature amplitude modulation (QAM) constellation, a novel energy-efficient unitary STBC is designed for a noncoherent multiple-input single-output (MISO) system with two transmitter antennas and one receiver antenna by using the QR decomposition. It is shown that the proposed UFCP-STBC design also allows for the blind unique identification of both the transmitted signals and channel coefficients as well as full diversity. In addition, an optimal unitary UFCP-STBC is devised to maximize the coding gain subject to a transmission bit rate constraint. The last approach is to demonstrate how the UFCP concept is applied to the systematic design of a coherent relay network coding system. A class of uniquely factorable Alamouti matrix pairs is proposed for the design of a novel amplify-forward relay network coding scheme, which allows the relay node to transmit its own information. By carefully making use of the Alamouti coding structure and strategically encoding the signals from the two antennas at the relay node, the resulting coding scheme enables the optimal full diversity gain and better coding gain for the ML detector. Comprehensive computer simulations show that the three uniquely factorable designs presented in this thesis have the best error performance compared to the current designs in literature.

abstract: Thesis

abstract: Candidate in Philosophy


title: INDEX MAPPING FOR ROBUST MULTIPLE DESCRIPTION LATTICE VECTOR QUANTIZER

contributor:
Dumitrescu, Sorina
Chen, Jun
Electrical and Computer Engineering

subject: MDLVQ IM IA BSA

abstract:
Multiple Description Coding (MDC) is a source coding technique which generates several descriptions of a signal such that the reconstruction gradually refines with the number of decoded descriptions. Conventionally, the design of MDC has largely focused on combating the description loss. This thesis considers the construction of robust multiple description lattice vector quantizers (MDLVQ) by addressing the problem of designing an index mapping able to combat bit errors.

We consider the scenario when the first description is received correctly at the decoder while the second one may carry bit errors. Our approach is to use a good assignment of the central lattice points to pairs of side lattice points, as developed in previous work, and design the mapping of the second description side lattice points to binary indexes such that the expected channel distortion to be minimized. In this thesis, we propose two methods to tackle this problem.

The first method is a binary switching heuristic algorithm, which starts with an initial mapping and iteratively switches two indexes such that the distortion is decreased. This algorithm only guarantees a locally optimal solution whose quality depends on the initial configuration.

The second approach attempts to increase the minimum Hamming distance between possible indexes in the second description when the first description is fixed. This is achieved using a structured construction as follows. First  the set of second description side lattice points is partitioned into Voronoi regions  of a carefully chosen coarse lattice. Next a channel code with high Hamming distance is picked, each Voronoi region is assigned a coset of this channel code and the side lattice points within each Voronoi region are mapped to binary sequences in the corresponding coset. We point out that in order to achieve good performance the mapping of Voronoi regions to cosets of the channel code must assign cosets close in Hamming distance to neighboring Voronoi regions. Two methods to achieve this goal are proposed and bounds on their performance are derived.

Finally, simulations are carried out to assess the practical performance of the proposed designs. Our results show significant performance improvement when the proposed index mappings are used versus non-optimized mappings.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: The Genetic Basis of Obesity

title: Using a High-throughput Candidate Gene Approach to Identify Novel Variants Associated with Obesity in Multi-ethnic Cohorts

contributor:
Meyre, David
Epidemiology

subject: Obesity Genetics Epigenetics pathophysiology

abstract: This work contains a summary of the current genetic, epigenetic and metagenomic knowledge of obesity, as well as an extensive overview of current genetic approaches in mouse models of obesity. Lastly, this work presents a candidate gene approach based on mouse models, which finds new variants associated with multiple obesity phenotypes in a multi-ethnic cohort.

abstract: The prevalence of obesity has been mainly be attributed to the rise in an obesogenic environment, in which individuals are more prone to high-dense energy foods and live a sedimentary lifestyle. Familial aggregation of obesity however, has led to numerous studies focused on understanding the genetic basis of this complex disorder. To this effect, this thesis summarizes the current knowledge of obesity genetics, including the monogenic, polygenic and epigenetics field. Given the tremendous contribution of animal models, especially mouse models, to our current knowledge of obesity genetics, this thesis summarizes the methodology of genetic studies in mice, and focuses on how the synergy between human and mouse studies has led to not only the discovery of obesity causal genes, but also their biological contribution to obesity. Lastly, this thesis summarizes a candidate gene approach based on the information from mouse models that have led to identification of a novel variant associated with body mass index (BMI), hip circumference and body adiposity index (BAI) in a multi-ethnic cohort.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Obesity is a heritable disease, and the genetic basis of obesity could result in better prevention and treatment options for this disorder. Obesity patterns are not uniform worldwide, and some ethnic groups are more prone to obesity than others, therefore having a multi-ethnic approach in studying obesity could yield to causal variants that could be generalized to all.


title: The Role of Macrophage Receptors in the Protection of the Murine Nasopharynx from Streptococcus pneumoniae

title: Macrophage-mediated immunity to pneumococcal colonization

contributor: Medical Sciences (Molecular Virology and Immunology Program)

subject:
Macrophage
Streptococcus pneumoniae
MARCO
Bacterial Colonization
Innate Immunity

abstract: Streptococcus pneumoniae (the pneumococcus) is one of the leading causes of death due to infectious disease in the world, with over one million deaths being attributed to this bacterium each year. While the majority of these deaths occur in children in developing nations, significant morbidity and mortality in the developed world, especially in the elderly, can be attributed to pneumococcal diseases such as bacterial pneumonia and meningitis. This is despite the near-universal use of anti-pneumococcal vaccines in these parts of the world. The work presented in this thesis describes the ways in which resident nasal macrophages respond to nasopharyngeal pneumococcal colonization, allowing for the protection of immunocompetent individuals from these diseases. This thesis describes the role of the macrophage scavenger receptor MARCO in recognizing the bacterium upon colonization, and the chain of events that are subsequently established. I have found that MARCO is vital in orchestrating the clearance of pneumococci from the nasopharynx in an expedient manner, as well as preventing the swift spread of bacteria to other tissues of the body early on in colonization. I also outline a role for regulatory micro-RNAs present in macrophages in the mounting of this anti-pneumococcal response via the induction of specific T cell populations. The collection of data found herein is an important resource for those attempting to understand the complex narrative that takes place between the pneumococcus and the innate immune system during a colonizing event and will lead to further discovery on how healthy individuals escape fatal pneumococcal disease.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: The bacterium Streptococcus pneumoniae is one of the most dangerous pathogens in the world, accounting for more one million deaths every year worldwide. This bacterium is also very common, with approximately one third of all people having some S. pneumoniae in their noses at any given time. The goal of this thesis is to provide a better understanding of how our immune cells interact with S. pneumoniae when it first enters our noses and how these initial interactions prevent healthy people from becoming sick. I have found that white blood cells called macrophages are crucial to these interactions. Macrophages are able to ‘eat’ the bacteria using a specialized protein called MARCO to grab onto them. This information will be vital in trying to develop new vaccines and treatments for S. pneumoniae-related diseases like bacterial pneumonia (lung infection) and meningitis (brain infection).


title: Impact of Kerr and Raman Nonlinear Effects on the Whispering Gallery Modes of a Spherical Microcavity

contributor:
Kumar, Shiva
Electrical and Computer Engineering

subject: Optical Microcavity

abstract:
Whispering gallery modes (WGM) microcavity have played an ubiquitous role due to their high quality factor Q and small effective mode volume $V_{eff}$. They are suitable for a broad range of applications and scientific research including cavity quantum electrodynamics (c-QED), sensing, parametric oscillation, frequency comb and so forth. The major nonlinear effect in silica is the Kerr nonlinearity that arises from the dependence of refractive index on the signal intensity. In this thesis, we focus on the theoretical analysis of Kerr and Raman nonlinear effects in a silica spherical microcavity. We derive several analytical models for various nonlinear effects, including self phase modulation (SPM), cross phase modulation (XPM) and stimulated Raman scattering (SRS).

The first part of this thesis develops a theoretical framework to describe the impact of Kerr nonlinearity, especially SPM on WGM. First a mathematical formulation to express $\chi^{(3)}$ in spherical co-ordinates is developed. We define the effective mode volume $V_{eff}$ for the the first time to analyze SPM effects by taking  $\chi^{(3)}$ tensor in spherical co-ordinates and it is found that the effective mode volume is always smaller than the physical volume of the microsphere. Simulation results show that whispering gallery mode undergoes a negative frequency shift proportional to the injected energy due to SPM.

Later, we extended the analysis to describe the nonlinear interaction between two WGMs. An analytical model is developed to describe the XPM effect in microsphere. Expressions for effective mode volumes and effective nonlinear coefficients to describe XPM are derived analytically. It is found that, when the effective mode volume increases, effective nonlinear coefficient becomes smaller and hence, we achieve a lower frequency shift.  An analytical expression for the coupling of whispering gallery mode is derived. The resonant frequency of a weak probe mode can be shifted by a strong pump mode due to XPM and the frequency shift of the probe is proportional to the pump energy. Also, An analytical expression for describing the Raman effect in a spherical microcavity is developed by including the delayed Raman response. The results show that the signal power is amplified due to the SRS effect.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Cellular reprogramming of human acute myeloid leukemia patient somatic cells

contributor:
Bhatia, Mickie
Biochemistry and Biomedical Sciences

subject:
acute myeloid leukemia
autologous therapies
cellular reprogramming
disease modeling
induced pluripotent stem cells
hematopoietic progenitor cells

abstract:
Acute myeloid leukemia (AML) is a fatal cancer of the human hematopoietic system characterized by the rapid accumulation of non-functional, immature hematopoietic cells in the bone marrow (BM) and peripheral blood (PB) of affected patients. Limited sources of safe hematopoietic stem/progenitor cells (HSPCs) for transplantation and incomplete mechanistic understandings of disease initiation, progression and maintenance have impeded advances in therapy required for improvement of long-term AML patient survival rates. Toward addressing these unmet clinical needs, the ability to generate induced pluripotent stem cells (iPSCs) from human somatic cells may provide platforms from which to develop patient-specific (autologous) cell-based therapies and disease models. However, the ability to generate iPSCs from human AML patient somatic cells had not been investigated prior to this dissertation. Accordingly, I hypothesized that cellular reprogramming of human AML patient somatic cells to iPSCs is possible and will enable derivation of autologous sources of normal and dysfunctional hematopoietic progenitor cells (HPCs).
	I first postulated that reprogramming AML patient fibroblasts (AML Fibs) to pluripotency would provide a novel source of normal autologous HPCs. Our findings revealed that AML patient-specific iPSCs devoid of leukemia-associated aberrations found in the matched bone marrow (BM) could be generated from AML Fibs, and demonstrated that this cellular platform allowed for the derivation of healthy HPCs capable of normal differentiation to mature myeloid lineages in vitro. During the tenure of these experiments we also redefined conventional reprogramming methods by discovering that OCT4 transcription factor delivery combined with culture in pluripotent-supportive media was minimally sufficient to induce pluripotency in AML and normal Fibs.
	Toward capturing and modeling the molecular heterogeneity observed across human AML samples in vitro, we next asked whether reprogramming of AML patient leukemic cells would enable generation of iPSCs and derivative HPCs that recapitulated dysfunctional differentiation features of primary disease. Our results demonstrated that conventional reprogramming conditions were insufficient to induce pluripotency in leukemic cells, but that generation of AML iPSCs could be reproducibly achieved in one AML sample when reprogramming conditions were modified. These AML iPSCs and their derivative HPCs harboured and expressed the leukemia-associated aberration found in the BM leukemic cells and similarly possessed dysfunctional differentiation capacities.
	Together, this body of works provides the proof of principle that cellular reprogramming can be applied on a personalized basis to generate normal and dysfunctional HPCs from AML patient somatic cells. These foundational findings should motivate additional studies aimed at developing iPSC-based cell therapies and disease models toward improving AML patient quality of life and long-term survival rates.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: OSL Dating of a Woodland Period Occupation at the Hare Hammock Ring and Mound Complex, Bay County, Florida

contributor:
Rink, Jack
Geography and Earth Sciences

subject:
Optically Stimulated Luminescence
Woodland Archaeology
Aluminum Oxide Dosimeters
Ring Middens

abstract:
This study used OSL dating to examine the chronological relationship between
two adjacent archaeological sites at the Hare Hammock complex in northwest Florida.
High-resolution vertical sampling was performed at 10cm intervals in profiles, one
corresponding to a Swift Creek burial mound, and the other to a Weeden Island ring
midden. This was done in order to determine the timing of occupations at the sites and
look for patterns in radiation dosimetry. The Swift Creek mound was found to have a
mean OSL age of 1835 +/- 68 years, consistent with archaeological expectations of the
site and the accepted range of Swift Creek culture. The subsequent Weeden Island
occupation was also found to have OSL ages within expectations, with a mean age of
1049 +/- 43 years that overlies a single age of 1511 +/- 372 years, corresponding to the
Late and Early Weeden Island periods, respectively. The general coherence with
radiocarbon dates and ceramic chronologies affirms the veracity of these OSL ages,
which were obtained using a very recently developed dosimetric technique that applies
Al2O3:C cylinders as in-situ dosimeters. These dosimeters indicated that the sediments at
Hare Hammock contain significant heterogeneity in beta dose rates. This study finds that,
under these circumstances, the best age results are obtained when applying the refined
dosimetric technique which combines the beta dose rate from NAA/DNC and gamma
dose rate from Al2O3:C dosimetry.

abstract: Thesis

abstract: Master of Science (MSc)


title: Uncovering the Anthropocenic Imaginary: The Metabolization of Disaster in Contemporary American Culture

contributor:
Clark, David L.
English and Cultural Studies

subject:
Anthropocene
American Literature
Ecocriticism
Cultural Studies

abstract: This dissertation examines the emergence of a discursive regime, which I call “the Anthropocenic Imaginary,” that invokes, instrumentalizes, and distorts the language of the earth sciences to bolster a neoliberal project of depoliticization. In recent years, the Anthropocene, a proposed geologic epoch, in which humanity figures as a planetary force and the planet exists as a human artifact, has become a frequent subject matter within American art and scholarship. It is now common for texts to refer, implicitly or explicitly, to the Earth’s transformation by humanity. This dissertation wagers that the Anthropocene should be understood not only as a geo-scientific descriptor, but also as a troping device, discursive regime, and cultural imaginary, which frames cultural and scholarly productions in a manner that legitimates the political and economic status quo. I argue that, despite appearing to be the product of studies that address the Earth’s anthropogenic modification, this discursive regime is a symptom of neoliberalism, a political, economic, and cultural ideology that schools subjects into privatized modes of being in order to induce acquiescence to the dominance of economic elites. I demonstrate that the discursive regime of the Anthropocenic Imaginary causes recent works of American scholarship, literature, and photography, which seem as though they should incite activism, to become depoliticized. I suggest that the Anthropocenic Imaginary is characterized by the metabolization of disaster, the transmutation of shocking material into something stultifying. I argue that it is possible to interpret the texts that the Anthropocenic Imaginary instrumentalizes otherwise than as legitimations of the status quo, and to bring to light the intractable disaster these works embody. Within this state of disaster, I suggest that it is possible to uncover a politically generative condition of non-normativity, which suggests that the way things are now cannot be made permanent.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: This dissertation responds to the advent within American culture of a range of discourses that posit humanity as a world-altering force and the planet as a human artifact. It seeks to answer the following questions: What is it about the present moment that makes the thought that humans are a terrestrial force appealing? Who benefits from the idea that humans are defined by the capacity to act as world-shapers? Against the scholarly consensus, I propose that this idea is not the product of scientific studies that announce the dawn of the Anthropocene, a geologic epoch characterized by anthropogenic modification of the earth system. Rather, I suggest that it is the effect of a discursive regime that I call “the Anthropocenic Imaginary,” which instrumentalizes the vocabulary of the earth sciences to legitimate the dominance of neoliberalism, a political, economic, and cultural ideology, which exerts a depoliticizing influence upon culture and scholarship.


title: Infants' ability to perceive multiple simultaneous auditory objects

contributor:
Trainor, Laurel J.
Psychology

abstract: In order to make sense of the world, infants must be able to segregate incoming acoustic information emitted by simultaneous sources. Auditory scene analysis refers to the ability to break down the complex sound signal arriving at the ear into the discrete objects giving rise to it (Bregman, 1990). Chapter 2 uses a conditioned head-turn paradigm to investigate whether 6-month-old infants are able to discriminate a mistuned harmonic within a complex tone, a stimulus that adults perceive as two separate auditory objects. Results suggest that infants are able to perform such a discrimination, but that their threshold is higher than adults. In adults, the perception of two auditory objects is associated with a neural correlate derived from event-related potential (ERP) recordings referred to as the object-related negativity (ORN). Chapter 3 investigates whether the ORN is elicited from infants in response to these mistuned stimuli, indicating that they hear the mistuned harmonic as a distinct auditory object. By 4 months, infants showed a significant frontally-positive, object-related response which transitioned to an adult-like ORN by 8 months. Chapter 4 uses a visual preference paradigm to determine whether 4-month-old infants have an expectation that the number of auditory objects they hear should match the number of objects they see. These infants looked significantly longer at trials where the number of audio and visual objects did not match, suggesting that they integrate information about auditory and visual sources from a young age. Collectively, these findings indicate that by 4 months, infants are able to discriminate a mistuned harmonic, and that this mistuning is perceived as a distinct auditory object that elicits a measurable response in the infant ERP. However, thresholds for discriminating mistuned harmonics and infant object-related waveforms continue to mature across the first year of birth.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Automation of Closed-Form and Spectral Matting Methods for Intelligent Surveillance Applications

contributor:
Chen, Jun
Electrical and Computer Engineering

subject:
Video processing
Visual-content analysis
Image processing
Video matting
Object detection
image matting

abstract:
Machine-driven analysis of visual data is the hard core of intelligent surveillance
systems. Its main goal is to recognize di erent objects in the video sequence and their
behaviour. Such operation is very challenging due to the dynamic nature of the scene
and the lack of semantic-comprehension for visual data in machines. The general
ow
of the recognition process starts with the object extraction task. For so long, this task
has been performed using image segmentation. However, recent years have seen the
emergence of another contender, image matting. As a well-known process, matting
has a very rich literature, most of which is designated to interactive approaches for
applications like movie editing. Thus, it was conventionally not considered for visual
data analysis operations.
Following the new shift toward matting as a means to object extraction, two methods
have stood out for their foreground-extraction accuracy and, more importantly,
their automation potential. These methods are Closed-Form Matting (CFM) and
Spectral Matting (SM). They pose the matting process as either a constrained optimization
problem or a segmentation-like component selection process. This di erence
of formulation stems from an interesting di erence of perspective on the matting process,
opening the door for more automation possibilities. Consequently, both of these
methods have been the subject of some automation attempts that produced some intriguing results.
For their importance and potential, this thesis will provide detailed discussion and
analysis on two of the most successful techniques proposed to automate the CFM and
SM methods. In the beginning, focus will be on introducing the theoretical grounds
of both matting methods as well as the automatic techniques. Then, it will be shifted
toward a full analysis and assessment of the performance and implementation of these
automation attempts. To conclude the thesis, a brief discussion on possible improvements
will be presented, within which a hybrid technique is proposed to combine the
best features of the reviewed two techniques.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Transient Simulations of the SLOWPOKE-2 Reactor Using the G4-STORK Code

contributor: Engineering Physics and Nuclear Engineering

subject:
Nuclear Physics
Reactor Physics
Nuclear Engineering
Simulations
Transient
Transient Simulations
GEANT4
G4-STORK
Computational Physics
SLOWPOKE-2

abstract: The goal of this thesis is to study the transient behaviour of the SLOWPOKE-2 reactor using Monte-Carlo simulations with the G4-STORK code. G4-STORK is a 3-dimensional Monte-Carlo code derived from the GEANT4 physics simulation toolkit. Methods were developed for the proper treatment of delayed neutrons and a lumped capacitance model was used to track the time-dependent fuel properties (temperature, density) based on the fission power. By validating the methods in G4-STORK with experimental measurements we hope to extend our understanding of reactor transients as well as further develop our methods to model the transients of the next generation reactor designs. A SLOWPOKE-2 reactor such as the one at RMC was chosen for simulation due to its compact size, and well-known transient response of control rod removal and measured temperature feedback. Static simulations in G4-STORK find a neutron flux of order 10^12 cm−2 s−1 which agrees with experiment and a control rod worth of (4.9 ± 2.0) mk compared to the experimentally measured worth of 5.45 mk. Transient simulations from rod pluck-out find similar trends to the experimental findings as our results suggest a negative temperature feedback due to the doppler broadening of the U-238 absorption spectrum which contributes to the overall safety mechanism seen in the SLOWPOKE reactor. It is determined that the methods in G4-STORK provide a reasonable ability to simulate reactor transients and it is recommended that a full-core thermal-hydraulics model be coupled to G4-STORK to achieve a higher level of accuracy.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Flow in thin polymer films: molecular structure, initial conditions, and boundary conditions

title: Flow in thin polymer films

contributor:
Dalnoki-Veress, Kari
Physics and Astronomy

subject: fluid dynamics, polymer thin films

abstract:
Surface tension driven flow is studied in films of viscous polymer liquid by monitoring the spreading of droplets or the capillary levelling of films with excess surface area. The research presented in this thesis is focused on three major themes where molecular details are important to flow: molecular anisotropy, interfacial friction, and the initial state of the film.

The effect of molecular anisotropy is studied by examining the dynamics of partially wetting diblock copolymer droplets using optical microscopy. The shape of the droplets is measured as they evolve towards equilibrium. In this system, it is found that energy is dissipated at the base of the droplets. This is consistent with a reduced interfacial friction at the liquid-substrate interface.

Flow dynamics are also found to depend on the symmetry of the initial film thickness profile. Thickness perturbations with different degrees of symmetry were created in an initially flat film using focused laser spike annealing. The films were allowed to flow under the driving force of surface tension, and using atomic force microscopy, the film thickness profile was measured as a function of time. We find the depth of the perturbations decreases as a power law in time, with a power law exponent that depends on the symmetry of the thickness perturbation.

The role of interfacial effects are explored by studying the flow in a film with zero interfacial friction: a freely-suspended film. Flow is measured in films with no interfacial friction using a technique which creates a film with a sharp step in the initial thickness profile. The excess surface area at the edge of the step drives flow, and information about the dynamics of the fluid is obtained by measuring the width of the step over time with atomic force microscopy. We observe flow that is consistent with plug flow: where the velocity of the fluid in the plane of the film is constant along the direction perpendicular to the film.

Finally, freely-suspended films provide a model system to study the nucleation and growth of pores in a membrane. By purposefully creating pores of different initial size, the critical radius for nucleation is measured as a function of the membrane thickness. The experimental results agree with a simple model in which the free energy cost at the perimeter of a pore is determined by the excess surface area due to the curved interface of the pore edge.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: CHRONIC PAIN SELF-MANAGEMENT SUPPORT IN PRIMARY HEALTH CARE

contributor:
MacDermid, Joy
Rehabilitation Science

subject:
Self-management
Chronic pain
exercise
pain education

abstract:
Chronic pain is one of the most frequent reasons for a primary health care visit and people with pain identify improved function as an important goal. Self-management support provides an opportunity to improve function for people with chronic pain, but existing evidence suggests negligible changes in function. This thesis includes five manuscripts with overarching objectives of improving the understanding of reductions in function related to pain and evaluating a new self-management program aimed at improving function for people with chronic pain.
The first manuscript is a cross-sectional evaluation of factors associated with reduced function in people with chronic pain referred for self-management support in primary health care. The findings suggest number of medications, depressive symptoms, cognitive factors associated with pain, mechanical hyperalgesia, and duration of symptoms explain 63% of the variance in function in people with chronic pain, multiple comorbidities, and barriers to accessing healthcare.
The second manuscript is a case-series describing the participation and outcomes of six participants in Chronic pain self-management support with pain science education and exercise (COMMENCE). This study contributes to the literature by detailing the COMMENCE intervention and describing the varied responses of six participants.

The third and fourth manuscripts are a protocol for a randomized controlled trial (RCT) and a completed RCT evaluating the effectiveness of COMMENCE in comparison to a wait-list control. The results suggest COMMENCE improves function for people with chronic pain (mean difference = -8.0 points on the Short Musculoskeletal Function Assessment; 95% confidence interval: -14.7 to -1.3).
The fifth manuscript is a planned secondary analysis of the RCT described above. This study suggested people with a greater number of comorbidities are likely to have poorer function at the end of COMMENCE after controlling for age, gender, and baseline function. Together, these factors explained 63% of the variance in function.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Chronic pain is associated with suffering, disability, and health care costs. This thesis includes five papers aimed at better understanding reduced function and evaluating a new self-management program for people living with chronic pain. The results of this research suggests people with more medications, longer lasting pain, negative thoughts and emotions related to their pain, and sensitivity to pressure are more likely to have poor functional abilities. A new self-management approach, Chronic pain self-management support with pain science education and exercise (COMMENCE), is described and evaluated. The results suggest people with chronic pain participating in COMMENCE experience greater improvements in function than people on a wait-list for the program. It appears people living with more chronic health conditions are likely to have poorer function at the end of the program. The findings of this thesis may help to inform management of chronic pain in primary healthcare.


title: RAPTOR-CODED FREE-SPACE OPTICAL COMMUNICATION EXPERIMENT

contributor:
Hranilovic, Steve
Electrical and Computer Engineering

abstract:
Free-space optical (FSO) communications are attractive in a host of applications, such as last-mile connections with backbone networks, due to their high data rates, license-free operation, low interference and ease-of-deployment. However, FSO communication systems suffer from availability issues mostly caused by bad weather conditions, thus preventing the widely deployment of FSO communication
technology.
Raptor codes are a class of fountain codes which adapt to varying channel conditions. The rateless property of Raptor codes makes them ideal for channels with high vulnerability such as FSO channels. This work presents a performance evaluation of two classes of Raptor codes in FSO communications: Raptor 10 and
RaptorQ codes. Both of the Raptor codes are capable of improving the reliability of FSO communications and adapting FSO data rates regardless of channel conditions. Compared with the Raptor 10, RaptorQ codes are capable of offering more robust communication performance.                                                  This work presents the software implementation of soft-switching hybrid FSO/LAN link using a Raptor 10 code. Preliminary experimental measurements show that the hybrid link could exploit the bandwidth of both links and avoids availability issues caused by harsh weather conditions.                                       This work also includes an FPGA-based hardware implementation of a Raptor 10 coded FSO link with focus on the receiver architecture. A complete hardware architecture of Raptor 10 decoder is presented in this work. The hardware structure of a pipelined receiver is proposed and evaluated, showing the important role of Raptor codes in FSO communications. This work serves as the first step towards the FPGA-based hardware implementation of soft-switching hybrid FSO/RF link using Raptor codes.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: TIMING OF THE EMPLACEMENT OF ANCIENT COASTAL DEPOSITS OF GEORGIA AIDED BY GROUND PENETRATING RADAR AND DETERMINED BY OPTICALLY STIMULATED LUMINESCENCE AND ELECTRON SPIN RESONANCE OPTICAL DATING

contributor:
Rink, William, Jack
Earth Sciences

subject:
GEORGIA
ANCIENT COASTAL DEPOSITS
GROUND PENETRATING RADAR
OPTICALLY STIMULATED LUMINESCENCE
ELECTRON SPIN RESONANCE OPTICAL DATING

abstract:
ESR, OSL and TT-OSL dating methods were applied to samples collected from six of the Ancient Coastal Deposits (ACDs) along the southern Georgia Coastline.  Samples were collected from the Princess Anne (the youngest and most seaward ACD), Pamlico, Talbot, Penholoway, Wicomico, and Okefenokee ACDs with the goal of determining the age of formation of these features.  Ground Penetrating Radar (GPR) was used to determine the subsurface morphology and target lithologies for age determination.  OSL and TT-OSL dating was attempted on samples collected from the youngest two ACDs, the Pamlico and Princess Anne, at McMaster Universities AGE Lab.  ESR samples collected from all of the ACDs studied were measured at Florida State University as well as Osaka University.  ESR analysis measured the Al signal, the Ti-Li signal, measured using two different methods, as well as the Ti-H signal.  A number of low additive dose points were added to the ESR dose plan to attempt to create a better dose response curve for the low saturating Ti-H signal in attempt to better utilize the signal.
While the geochronological methodology did not prove useful for determining the age of all of the ACDs it did result in depositional age estimates for the Cypresshead Formation at 433-2978 ka and Satilla Formations at 243-417 ka using the Ti-Li ESR signal as a maximum age estimate.  The GPR, ESR, and core data all point to the conclusion that the ACDs of the Georgia Coast are geomorphic modifications and not the result of a unique depositional process.  Based on the discrepancy between the depositional age of the Cypresshead and Satilla Formations as determined by ESR in this study and the ages of the ACDs published by others from Georgia (Markewich et.al., 2013) or other areas of the Atlantic Coast (Wehmiller, 2004; Willis, 2006) it can be concluded that paleo sea-levels modified the Cypresshead and Satilla Formations in to the morphology seen today at some point after their initial deposition.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract:
ESR, OSL and TT-OSL dating methods were applied to samples collected from six of the Ancient Coastal Deposits (ACDs) along the southern Georgia Coastline with the goal of determining the age of formation of these features.  Ground Penetrating Radar (GPR) was used to determine the subsurface morphology and target lithologies for age determination.  A number of low additive dose points were added to the ESR dose plan to attempt to create a better dose response curve for the low-dose saturation of the Ti-H signal in attempt to better utilize the signal.
While the geochronological methodology did not prove useful for determining the age of all of the ACDs, it did result in depositional age estimates for the Cypresshead Formation at 433-2978 ka and Satilla Formations at 243-417 ka.  The GPR, ESR, and core data all point to the conclusion that the ACDs of the Georgia Coast are geomorphic features without unique depositional events.


title: PREDATOR-PREY MODELS WITH DISTRIBUTED TIME DELAY

contributor:
Wolkowicz, Gail S.K.
Mathematics and Statistics

subject:
distributed delay
predator-prey models
chemostat
bifurcation theory

abstract:
Rich dynamics have been demonstrated when a discrete time delay is introduced in a simple
predator-prey system. For example, Hopf bifurcations and a sequence of period doubling bifurcations that appear
to lead to chaotic dynamics have been observed.  In this  thesis  we consider  two different
predator-prey models: the classical Gause-type predator-prey model and the chemostat predator-prey model.
In both cases, we explore how different ways of modeling the time between the first contact of the predator
with the prey and its eventual conversion to predator biomass affects the possible  range of  dynamics
predicted by the models. The  models we explore are systems of  integro-differential equations with
delay kernels from various distributions including the gamma distribution of different orders, the uniform
distribution, and the Dirac delta distribution.  We study the models using bifurcation theory
taking the mean delay as the main bifurcation parameter.  We use both an analytical approach and a
computational approach using the numerical continuation software  XPPAUT and DDE-BIFTOOL.
First, general results common to all the models  are established.  Then, the differences due to the selection
of particular delay kernels are considered.  In particular, the differences in regions of stability
of the coexistence equilibrium are investigated. Finally,  the effects on the predicted range of dynamics
between the classical Gause-type  and the chemostat predator-prey models
are compared.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Hybrid Energy Storage System Using Series-Parallel Reconfiguration Technique

contributor:
Emadi, Ali
Electrical and Computer Engineering

subject:
DC/DC converters
electric vehicles
electrified powertrains
energy storage system
hybrid electric vehicles
hybrid energy storage system
power electronics
ultracapacitors

abstract:
Technology advancements enable and encourage higher system electrifications in various applications. More electrified applications need more capable and higher performing sources of energy in terms of power delivery, power regeneration, and energy capacity. For example, in electric, hybrid electric, and plug-in hybrid electric vehicle applications (EVs, HEVs, and PHEVs), the power and energy ratings of the vehicle energy storage system (ESS) have a direct impact on the vehicle performance. Many researchers investigated and studied various aspects of hybrid energy storage systems (HESS) wherein multiple ESSs are combined together to share system loads, increase ESS capabilities, and cycle life. Various configurations and their application specific topologies were also proposed by other researchers; the potential of HESS has been proven to be very promising.

In this research, the goal is to present the theory of a HESS configuration that
has not been discovered thus far. This HESS configuration is called a series-parallel
reconfigurable HESS (SPR-HESS) since it is capable of recombining multiple storage
systems into different series, parallel, or series-parallel configurations, via power electronic converters, to accommodate different operation modes and load requirements. Simulations, as well as experimental verifications, are presented in this thesis.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: TOWARD MOLECULAR IMAGING PROBES TO DETECT CRYPTIC BACTERIAL INFECTIONS

contributor:
BERTI, PAUL
Chemical Biology

subject: molecular imaging of bacterial infection

abstract: Infectious diseases represent one of the leading causes of death globally. Prompt diagnosis is essential for the onset of clinical treatment but certain cases of underlying bacterial infection deep in the body can remain undiagnosed for weeks. Hidden bacterial infection is the leading cause of fever of unknown origin (FUO), which is observed in 2 % of all hospital admissions around the world. Molecular imaging of bacterial infections is the ideal non-invasive diagnostic tool, but all available probes also detect inflammation. Two targets were selected for development of bacteria-specific molecular imaging probes, namely iron-uptake pathways and peptidoglycans involved in the synthesis of the cell wall. Both, Gram-positive and Gram-negative bacteria use iron-binding molecules called siderophores to scavenge iron from their surroundings.  The structural similarities between Fe3+ and Ga3+ allow siderophores to be radiolabelled with 67/68Ga and visualized by nuclear medicine techniques. The clinically proven siderophore Deferoxamine (Dfo) has a plasma half-life of only 5.5 min that does not favor its direct use as a probe. Dfo derivatives with improved pharmacokinetics properties were designed and tested on Staphylococcus aureus cultures. The ciprofloxacin and the ethyloxycarbonyl derivatives of DFO at the primary amino position were among the most successful conjugates targeting the siderophore active-transport mechanism and reaching high relative uptake rates. Furthermore, the peptidoglycan pathway of Gram-positive bacteria was in vitro targeted with vancomycin conjugated to 67Ga-Dfo which showed even higher labelling capacity than 67Ga-Dfo within a few minutes of exposure.  In vitro siderophore studies remain challenging due to the lack of methods for the preparation of rigorously iron-depleted media.  We developed an iron chelating method with the goal of creating iron-free growth media.

abstract: Thesis

abstract: Master of Science (MSc)


title: EXAMINING ZINC RELEASE FROM PLATELETS AND ITS MODULATION OF CLOT STRUCTURE AND FIBRINOLYSIS

contributor:
WEITZ, JEFFREY
Biochemistry

subject: ZINC COAGULATION FIBRINOLYSIS PLATELETS

abstract: Zinc (Zn2+) is an abundant metal ion that circulates in the body. Within hemostasis, Zn2+ participates in platelet aggregation, coagulation, and fibrinolysis. At the site of injury, Zn2+ released from activated platelets accelerates coagulation and attenuates fibrinolysis. How Zn2+ regulates these processes on a molecular level has not been extensively examined. We hypothesized that Zn2+ released from platelets binds serine proteases involved in coagulation or fibrinolysis and modulates their proteolytic activity, thus controlling the rate of clot formation and lysis. We show that Zn2+ concentrations released from activated platelets are sufficient to modulate clot formation and fibrinolysis. We show in vitro that Zn2+ binds to fibrinogen with high affinity, accelerates fibrin monomer polymerization, and modifies clot structure. Zn2+ promotes clot stability by increasing fiber diameter, reducing fibrin fiber elasticity, and increases clot porosity. Although it might be predicted that these modifications would enhance clot degradation by enabling greater distribution of lytic enzymes through the more porous fibrin network, we showed the opposite. Thus, we demonstrated that Zn2+ binds to plasminogen activators and plasmin with high affinity and down-regulates their protease activity, which delays lysis. This adds to previous studies that showed that both coagulation and fibrinolysis are regulated by Zn2+ ions. These data support the functional role of Zn2+ in hemostasis.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Unbounded Continuous Logic and Metric Geometry

contributor:
Hart, Bradd
Mathematics

abstract:
This thesis studies continuous logic and its application to metric geometry. An adaptation of continuous logic for unbounded pointed metric spaces is introduced and developed. Background on CAT(k) spaces, asymptotic cones, symmetric spaces, and buildings is provided. Various definability results are proved regarding geodesic rays and the building structure on them. We conclude with a proof of the instability of asymptotic cones of a certain class of
symmetric spaces.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Adaptive Characteristics of Fiber-Reinforced Elastomeric Isolators

contributor:
Tait, Michael J.
Konstantinidis, Dimitrios
Civil Engineering

subject:
base isolation
seismic isolation
fiber-reinforced
elastomeric isolators

abstract:
Seismic base isolation has become an increasingly common approach to reduce earthquake induced losses. Base isolation aims to decouple  structures, such as buildings or bridges, from strong ground motions through the introduction of a flexible layer, typically located at the foundation. Base isolation is a well-established concept and accepted as an effective method of protecting both the structure and its contents from damage due to earthquakes.
Elastomers are ideal for base isolation due to their soft material properties and ability to undergo large recoverable strains. Steel-reinforced elastomeric isolators (SREIs) have been widely applied as base isolators; however, the weight and cost of SREIs have been perceived as barriers to the widespread application of base isolation. In order to alleviate these concerns, it has been proposed that the steel reinforcement could be replaced with lighter fiber reinforcement with similar tensile properties as steel. Recent investigations have demonstrated that fiber-reinforced elastomeric isolators (FREIs) are viable and have desirable characteristics.
An additional proposed cost saving measure was to place the FREI unbonded between the upper and lower supports. The combination of the flexible fiber reinforcement and the unbonded application resulted in a unique rollover deformation under horizontal displacement. Rollover causes a nonlinear force-displacement relationship characterized by a softening and stiffening phase. This nonlinear relationship is believed to be advantageous and to allow the performance of the device to be tailored to the earthquake hazard level.
This work investigates the adaptive characteristics of unbonded FREIs. It is demonstrated that the softening and stiffening characteristics of the isolator can be altered through modifications to the isolator or to the surrounding support geometry. Equations are developed to predict the horizontal force-displacement relationship. Furthermore, simple expressions appropriate for use in building and bridge design codes are proposed for critical isolator properties. Potential limitations introduced due to the unbonded application are identified and addressed through the development of a new partially bonded hybrid isolator. It is demonstrated that unbonded FREIs are highly versatile and a potentially competitive device appropriate for widespread application in developed and developing countries.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Earthquakes remain a significant and potentially devastating threat to both developed and developing countries. Structural elements within a building, such as beams and columns, must deform considerably to accommodate the relative floor displacements that develop due to ground motion. Conventional construction materials are not capable of undergoing these large deformations without irreversible and potentially catastrophic damage. The introduction of a flexible layer at the foundation level of a structure, using elements known as isolators, can dramatically reduce damage. The deformation is concentrated at the flexible layer, which can undergo large displacements without any damage. This concept, known as base isolation, protects both the structure and its contents. Traditional isolators are expensive, thus far hindering the application of base isolation systems. A novel isolator design has been proposed that has the potential for widespread economical application. To increase the application, building codes need to be developed, requiring substantial research on the isolator properties. A key component of the novel isolator is the ability to alter the isolator geometry to further enhance the response. This is validated through experimental testing and complex computer models.


title: PROCOAGULANT EFFECTS OF PLATINUM-BASED LUNG CANCER CHEMOTHERAPY AGENTS

contributor: Medical Sciences (Blood and Cardiovascular)

subject:
Chemotherapy
Lung Cancer
Thrombosis
VTE
Platinum

abstract:
Chemotherapy-associated thrombosis is a common complication in cancer patients. Cancer patients have a 5- to 7-fold increased risk for a thrombotic event compared to healthy individuals. While the overall risk for a thrombotic event in lung cancer patients is approximately 1.4%, the rates of thrombosis vary depending on the stage of the disease and the chemotherapeutic agents used. Activation of coagulation after initiation of chemotherapy has been reported in clinical studies. However, the mechanisms by which lung cancer chemotherapy agents modulate coagulation in lung cancer patients are not completely understood. The focus of this thesis is to investigate the mechanisms by which chemotherapy agents cisplatin, carboplatin, gemcitabine, and paclitaxel (in platinum-based combinations) induce procoagulant effects utilizing in vitro and in vivo approaches.
	First, we investigated the mechanisms by which lung cancer chemotherapy modulates cell-surface tissue factor (TF) activity on endothelial cells (HUVEC), monocytes, and non-small cell lung carcinoma (NSCLC) A549 cells. We observed that treatment of all three cell lines with platinum-based lung cancer chemotherapy increased cell surface TF activity. We found that the increased TF activity on chemotherapy-treated monocytes was due to increased phosphatidylserine (PS) exposure, whereas the increased TF activity on HUVEC and A549 cells was due to protein disulfide isomerase (PDI)-mediated decryption of TF. These studies demonstrate that lung cancer chemotherapy agents can exert procoagulant effects by increasing PS exposure and by inducing TF decryption on healthy and tumour cells.
	Next, we determined the effects of lung cancer chemotherapy on the generation of microparticles (MP) and the impact of MPs on thrombin generation. Our in vitro and in vivo studies demonstrate that lung cancer chemotherapy agents increase the generation of TF- and PS-positive MPs from tumour cells and that the MPs contribute to thrombin generation in a FVII-dependent manner. We also investigated the role of cell-free DNA (CFDNA) in mediating procoagulant effects induced by lung cancer chemotherapy agents. We found that lung cancer chemotherapy agents induce CFDNA release from healthy host neutrophils and that this leads to additional generation of thrombin by the intrinsic pathway of coagulation.
Lastly, CFDNA levels have been shown to increase in cancer models through formation of neutrophil extracellular traps (NETs). Formation of NETs by NETosis, a process by which neutrophils release extracellular web-like structures composed of DNA, histones, and granular proteins, is dependent on histone citrullination by protein arginine deaminase-4 (PAD-4). In addition, PAD4 inhibition prevents NET formation. Therefore, we wanted to demonstrate that the neutrophil-derived CFDNA release induced by lung cancer chemotherapy is PAD4-dependent. Chemotherapy treatment of PAD4 knockout mice failed to increase CFDNA levels. Furthermore, chemotherapy-treatment did not increase thrombin generation in PAD4 knockout mice. This suggests that chemotherapy-induced CFDNA release occurs through NETosis.
	In conclusion, lung cancer chemotherapy leads to increased thrombin generation which occurs through increased TF decryption, MP generation, and CFDNA release. Therefore, lung cancer chemotherapy results in simultaneous activation of the extrinsic and intrinsic pathways of coagulation. These studies provide novel insight into the mechanisms of lung cancer chemotherapy-associated thrombosis.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Application of Decision Theory and Dynamic Programming to Adaptive Control Systems

contributor:
Sinha, N.K.
Electrical Engineering

subject: adaptive control, implementation,contradictory

subject: optimal controller,

abstract:
It is generally assumed that the implementation of adaptive control requires a precise identification of plant parameters. In the case of a system with varying parameters, the identification problem gets very involved, as speed of identification and accuracy are contradictory requirements.
In this thesis it has been shown that using a feedback policy, the optimal controller is relatively· insensitive to changes in plant parameters as long as these lie within some specified ranges. It is, therefore, concluded that, with such an arrangement, adaptive control can be implemented if one has only the knowledge of the ranges within which the parameters
of the plant lie. Thus identification can be carried on more rapidly, as stringent accuracy is no longer necessary.

abstract: Thesis

abstract: Master of Engineering (ME)


subject: adaptive control,  plant parameters, feedback policy

abstract:
It is generally assumed that the implementation of adaptive control requires a precise identification of plant parameters. In the case of a system with varying parameters, the identification problem gets very involved,as speed of identification and accuracy are contradictory requirements.
In this thesis it has been shown that using a feedback policy, the optimal controller is relatively· insensitive to changes in plant parameters as long as these lie within some specified ranges. It is, therefore, concluded that, with such an arrangement, adaptive control can be implemented if one has only the knowledge of the ranges within which the parameters
of the plant lie. Thus identification can be carried on more
rapidly, as stringent accuracy is no longer necessary.

abstract: Thesis

abstract: Master of Engineering (ME)


title: Models for Managing Supply and Demand Uncertainties in Supply Chains

contributor:
Hassini, Elkafi
Business

subject:
Supply Chain
Supply Uncertainty

abstract:
We propose a classification framework for the operations management literature that has looked at pricing and ordering in supply chains when supply and/or demand are uncertain. We then focus on developing three new models for managing supply and demand uncertainties in supply chains.

In the first model, we study a two period sourcing problem of a firm under two sets of contracts. The contracts differ in terms of acquisition costs and the level of risk that they impose on the firm. We provide the conditions where the optimum solution is unique and also explore the behaviour of the optimum solution analytically and numerically. One application of our model is in the agribusiness supply chain and we provide numerical examples based on data from the almond industry in California.

In the second model we look at a joint ordering, pricing and capacity planning problem. We characterize the optimum policy both in single and multi-period cases. In addition, we study the impact of fixed production costs on the optimum policy.

The third model is devoted to coordination between a buyer and a supplier where there is a possibility of improving the supplier by both players. We analyze the problem under a Stackelberg game setting where the buyer is the leader. We show that the buyer either tries to amplify the investment of the supplier by order inflation or assumes all the investment costs. We investigate the behaviour of the optimum solution under different strategies.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Genetic Analysis of a Hybrid Cross between Cryptococcus neoformans and Cryptococcus deneoformans

contributor:
Xu, Jianping
Biology

abstract:
Cryptococcus neoformans is a deadly human fungal pathogen that primarily affects
immunocompromised individuals. Matings with the closely related species Crypto-
coccus deneoformans produce viable, yet atypical offspring. Previous research has
demonstrated that the hybrids are aneuploid or diploid, and have low germination
rates and suppressed recombination. In addition, numerous large-scale genomic re-
arrangements have been identified between C. deneoformans and C. neoformans. We
conducted a cross between CDC15, a clinical drug-resistant isolate of C. neoformans
and JEC20, a laboratory derived strain of C. deneoformans. We collected 230 hy-
brid progeny and determined their genotypes using codominant PCR-RFLP markers.
Three separate analyses were conducted in order to better understand the genet-
ics of these hybrids. These revealed that there is mitotic recombination during the
production of the hybrids, that there are genetic incompatibilities between C. neofor-
mans and C. deneoformans, and that differences between the two species in virulence-
related traits are controlled by multiple quantitative genetic loci. The results not only
improve our understanding of the hybrid progeny themselves, but also of Cryptococcus
in general.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Robust Models for Accommodating Outliers in Random Effects Meta Analysis: A Simulation Study and Empirical Study

contributor:
Beyene, Joseph
Mathematics and Statistics

subject:
meta-analysis
outliers
simulation study
empirical study
robust model
random effects

abstract:
In traditional meta-analysis, a random-effects model is used to deal with heterogeneity and the random-effect is assumed to be normally distributed. However, this can be problematic in the presence of outliers. One solution involves using a heavy tailed distribution for the random-effect to more adequately model the excess variation due to the outliers. Failure to consider an alternative approach to the standard in the presence of unusual or outlying points can lead to inaccurate inference. A heavy tailed distribution is favoured because it has the ability to down-weight outlying studies appropriately, therefore the removal of a study does not need to be considered.

In this thesis, the performance of the t-distribution and a finite mixture model are assessed as alternatives to the normal distribution through a comprehensive simulation study. The parameters varied are the average mean of the non-outlier studies, the number of studies, the proportion of outliers, the heterogeneity and the outlier shift distance from the average mean. The performance of the distributions is measured using bias, mean squared error, coverage probability, coverage width, Type I error and power.  The methods are also compared through an empirical study of meta-analyses from The Cochrane Library (2008).

The simulation showed that the performance of the alternative distributions is better than the normal distribution for a number of scenarios, particularly for extreme outliers and high heterogeneity. Generally, the mixture model performed quite well.

The empirical study reveals that both alternative distributions are able to reduce the influence of the outlying studies on the overall mean estimate and thus produce more conservative p-values than the normal distribution.

It is recommended that a practitioner consider the use of an alternative random-effects distribution in the presence of outliers because they are more likely to provide robust results.

abstract: Thesis

abstract: Master of Science (MSc)


title: SELECTIVE SEROTONIN REUPTAKE INHIBITORS AND THE RISK OF TYPE 2 DIABETES MELLITUS

title: SSRIs and the risk of T2DM

contributor: Medical Sciences (Division of Physiology/Pharmacology)

abstract:
Major Depressive Disorder (MDD) is a wide spread psychiatric disorder which affects more than 350 million people worldwide. Of the current available treatments, Selective Serotonin Reuptake Inhibitors (SSRIs) are the most commonly prescribed. Long-term SSRI use has been associated with the onset of Type 2 Diabetes (T2DM) in adults. T2DM is driven by beta cell dysfunction and hence we wanted to investigate the mechanism(s) by which SSRIs were causing beta cell demise. We have found that fluoxetine, more
commonly known as Prozac®, does in fact disturb beta cell function by inducing mitochondrial dysfunction and thereby oxidative damage.
Interestingly, women are twice as likely to experience MDD, and this risk peaks during childbearing years. As a result, up to 1 in 10 pregnancies are complicated with SSRIs. This is an astonishing number considering the long-term effects of these drugs on the children are unknown. Within this thesis I report for the first time, the long-term metabolic outcomes of fetal and neonatal exposure to SSRIs in a rodent model. We have found that antenatal exposure to fluoxetine results in altered glucose homeostasis and impaired insulin sensitivity in the adult offspring. Furthermore we have shown that
epigenetic modifications may be implicated in the increased incidence of fatty liver in these offspring. These findings demonstrate a predisposition to the development of obesity and T2DM into adulthood. These findings are novel and have clinical importance with respect to mothers taking these drugs during pregnancy. Within this thesis we are not advising mothers with depression to discontinue medication. We are merely exploring the risks in a rodent model while acknowledging that a significant amount of research is
required before applying theses results to the human population.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: Pregnancy is a window of vulnerability for depression with prevalence rates estimated to be approximately 10%. Guidelines recommend that antidepressant medication should be considered for pregnant women with moderate to severe depression of which selective serotonin reuptake inhibitors (SSRI) are the most common. The aim of this project was to look at SSRI exposure during pregnancy and to determine whether this exposure can predispose the offspring to obesity and/or type 2 diabetes (T2DM). We have found that SSRI use during pregnancy may increase the risk of T2DM and fatty liver in the adult offspring. These findings raise new concerns about the metabolic health of children born to women who take SSRI antidepressants during pregnancy. While these findings suggests a significant outcome in rodents, further investigations are critical to understanding the complexities within this field before suggesting similar outcomes in humans.


title: Theta Burst Stimulation-Induced Metaplasticity:  Changing Tactile Perception and Physiology in Primary Somatosensory Cortex

contributor:
Nelson, Aimee J.
Kinesiology

abstract: Theta-burst stimulation (TBS) over human primary motor cortex evokes plasticity and metaplasticity, the latter contributing to the homeostatic balance of excitation and inhibition.  Our knowledge of TBS-induced effects on neighboring primary somatosensory cortex (SI) is limited and it is unknown whether TBS is capable of inducing metaplasticity within human SI.   Sixteen right-handed participants (6 females, mean age 23) received six different TBS protocols delivered over SI in separate sessions.  TBS protocols were delivered at 30 Hz (612 pulses) and included continuous TBS (cTBS), intermittent TBS (iTBS), cTBS followed by cTBS, iTBS followed by iTBS, cTBS followed by iTBS and iTBS followed by cTBS.  Dependent measures included the amplitude of the first and second somatosensory evoked potential (SEP) following median nerve stimulation and their paired-pulse ratio (PPR), and temporal order judgment (TOJ) performed on digits 2 and 3.  Dependent measures were obtained before and at 5, 25, 50 and 90 minutes following stimulation.  Results indicate similar effects following cTBS and iTBS; increased amplitude of the second SEP with marginal changes to PPR, and elevated TOJ thresholds.  CTBS-cTBS and iTBS-iTBS both demonstrated metaplasticity via measures of TOJ but with disparities in their direction and timing of effects.  I conclude that 30 Hz cTBS and iTBS protocols delivered in isolation induce similar plasticity in SI as measured by decreases in SI intracortical inhibition and impairments in TOJ performance, and when applied in multiples, produce metaplasticity effects on TOJ performance.

abstract: Thesis

abstract: Master of Science (MSc)


title: INVESTIGATING THE ROLE OF ESTRADIOL AND THE MUCOSAL MICROENVIRONMENT ON Th17 RESPONSES PRIMED BY DENDRITIC CELLS IN THE FEMALE GENITAL TRACT

title: ESTRADIOL INFLUENCES THE FUNCTION OF VAGINAL DENDRITIC CELLS

contributor: Medical Sciences (Molecular Virology and Immunology Program)

subject:
sexually transmitted infections
Th17
sex hormones
estradiol
HSV-2
Dendritic cells
microflora
mucosal immunity
anti-viral responses
antigen presenting cells
microenvironment

abstract:
Clinical and experimental studies have shown that estradiol (E2) can enhance protection against sexually transmitted infections such as HSV-2 and HIV-1. Antigen presenting cells (APCs) such as Dendritic cells (DCs) are critical for generating immune responses against these infections, and it is unclear whether unique factors present in the genital mucosa can influence immune responses by directly modulating the phenotype and function of local APCs. To address this, I hypothesized that sex hormones, such as E2 and innate factors in the local microenvironment can regulate the phenotype and function of vaginal APCs. The work summarized in this thesis addressed this central hypothesis.
In the first section of the thesis, I examined whether vaginal APCs were distinct in their phenotype and function compared to those in other mucosal tissues or spleen. The results show that the vagina was enriched in CD11c+ CD11b+ MHCII− DCs. Functionally, vaginal tissue cells (TC) and CD11c+ DCs were more potent inducers of Th17 responses in co-cultures with CD4+ T cells, compared to lung, small intestine or spleen APCs. E2 was critical for the conditioning of vaginal DCs to prime these Th17 responses through an IL-1-dependent pathway, indicating that sex hormones such as E2 can directly influence the function of vaginal APCs.
In the next section, I determined whether other co-factors in the genital microenvironment such as microflora and innate lymphocytes could also influence vaginal APC functions. We found that while microflora was not essential, IL-17 produced by innate lymphocytes was critical for the induction of IL-1 from DCs, and consequently for potentiating Th17 responses.
Finally, I attempted to develop an in vivo mouse model where the effect of E2 on vaginal APCs could be examined in the context of genital HSV-2 infection. I tested a 7-day injectable E2 and a 21-day E2 pellet delivery model, and found that both regimes had limitations for examining E2-effects on anti-viral responses. Yet, subsequent to the work done in this thesis, we were able to confirm our observations of E2-conditioned Th17 responses in vivo in an intranasal immunization model utilizing E2 pellet delivery, and thereby addressed the mechanism underlying enhanced anti-viral protection following E2-treatment.
In conclusion, this is the first study to show the effect of E2 on genital tract APCs and their ability to prime Th17 responses.  It provides future avenues to examine whether modulation of this microenvironment can help optimize vaccine-induced immune responses against STIs. On a more fundamental level, it highlights the need to consider the inherent distinctions in APC populations among different mucosal tissues.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: MOLECULAR GENETIC STUDY OF REPRODUCTIVE SYSTEM DEVELOPMENT IN THE NEMATODE CAENORHABDITIS BRIGGSAE

title: GENETICS OF REPRODUCTIVE SYSTEM DEVELOPMENT IN C. BRIGGSAE

contributor:
Gupta, Bhagwati P
Biology

abstract:
The nematode C. briggsae, a relative of C. elegans, is a widely used animal model
for comparative studies to understand evolution of gene function and developmental
mechanisms. To investigate differences in the mechanism of reproductive system
development, genetic screens were conducted in our laboratory to isolate C.
briggsae mutant strains that display abnormal vulva and vulva-uterine connection. The
screens yielded at least seven genes whose loss of function results in a multivulva
phenotype and 13 genes that result in egg-laying defective and protruding vulva
phenotypes. Molecular cloning experiments were carried out to determine the identities of
these genes, leading to the identification of five C. elegans orthologs that function at
different steps of vulval development process. Three of these, Cbr-lin-1, Cbr-lin-31 and
Cbr-pry-1, encode components of Ras and Wnt pathways. The remaining genes are
uncloned and include novel regulators of C. briggsae vulval development. Our
comparative study of vulval development in C. briggsae and C. elegans has revealed
differences in three homologous processes – inter-VPC distance, fate specification and
anchor cell migration. Together these studies demonstrate that despite the overall
similarity in vulval cell numbers and morphology between the two Caenorhabditis
species, the underlying genetic programs include both conserved and divergent functional
components. Additionally, this work highlights key resources such as mapping tools,
mutant strains and CRISPR genome editing technology that have been developed to
facilitate the use of C. briggsae in a comparative and individual context.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Evolution of a Municipal Solid Waste Disposal System: A Design Case Study

contributor:
Kardos, G.
Mechanical Engineering

subject:
waste disposal
municpal
solid waste disposal system

abstract: A record of the design evaluation of a municipal solid waste disposal system has been made. The record was arranged chronologically on a process basis. The author had presented his analyses of the design influences. Emphasis has been put on the major influences. Observations and analyses of a more general nature, plus personal views of the case study method are also given. Recommendations for further study of this project are provided in a test proposal outline for the system.

abstract: Thesis

abstract: Master of Engineering (ME)


title: The development of cellular metabolomic platforms and their applications

contributor:
McCarry, Brian
Bowdish, Dawn
Chemistry

subject:
metabolomics
cell
HILIC
bacteria
macrophage
Streptococcus intermedius
Sinorhizobium meliloti
LC-MS
GC-MS
comprehensive metabolomics
targeted metabolomics

abstract: In this thesis, an analytical platform was designed and applied to various in vitro bacterial and eukaryotic cell cultures. An extraction and an analytical protocol were developed for comprehensive and simultaneous analysis of both lipid and polar metabolites for intra- and extracellular metabolomics using HILIC-LC-TOF-MS. This analytical platform was applied to four diverse research questions such as the effect of oxygen environment on growth, the interplay between gene expression and metabolism, metabolic changes that occur with age, and PAH toxicity. Specifically: (i) the effect of oxygen on the growth, physiology and metabolism of the Gram positive Streptococcus intermedius were investigated by comprehensive intra- and extracellular metabolomes and transcriptome. (ii) Metabolic insights into the role of the multipartite genome of the Gram negative bacteria Sinorhizobium meliloti and its metabolic preferences in a nutritionally complex environment. (iii) Age-associated metabolic dysregulation in murine bone marrow-derived macrophages during bacterial lipopolysaccharide-induced inflammation. (iv) Comprehensive intracellular metabolomic profiles of Sinorhizobium meliloti to sub-lethal exposure of individual or mixtures of polycyclic aromatic hydrocarbon revealed additive and dose-dependent effects. This thesis has demonstrated the versatility of the designed analytical platform and its use for diverse research in cell biology.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Dynamic Simulation of a Multiproduct Chemical Plant

subject:
Modular Approach
change-over operation
chemical plant
fat hydrolysis process
DYNSYS

abstract: This report deals with the use of the "Modular Approach", in the simulation of change-over operations, for a continuous multiproduct chemical plant. A dynamic model of the continuous fat hydrolysis process was built, with the DYNSYS framework, with the purpose of evaluating the usefulness of this programme in simulating different change-over operation policies. Operator's activities were simulated making use of an interactive version of DYNSYS, demonstrating its value for studying alternate changeover policies and possible as a training device. Supervisory control was implemented in order to automate the change-over operations, simulating the functions of a small computer controlling the process. Improved operating policies for change-over are proposed and the validity of the simulation is discussed from both a practical and a theoretical point of view.

abstract: Thesis

abstract: Master of Engineering (ME)


title: Seneca Township: A Study in Settlement and Land Utilization

contributor:
Wood, H. A.
Geography

subject:
Seneca Township
geography
Haldimand County
differentiation
physical environment
historical geography
land use

abstract: This thesis was presented to the Department of Geography in partial fulfilment of the requirements for the degree Bachelor of Arts.

abstract: An abstract is not provided.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: Dopamine mediated modulation of electrotactic swimming behaviour in Caenorhabditis elegans

contributor:
Gupta, Bhagwati
Biology

subject: C. elegans, dopamine, electrotaxis, movement behaviour

abstract:
The nematode C. elegans is a multicellular model organism to study the neuronal-basis of behaviour. C. elegans demonstrates an innate response to swim towards the cathode in the presence of a DC electric field(EF), a behaviour known as “electrotaxis”. We examined mutants affecting sensory and dopaminergic neurons and found that these mutants moved with reduced speed with intermittent pauses, abnormal turning, and slower body bend. A similar phenotype was observed in worms treated with neurotoxins 6-OHDA, MPTP and rotenone. Pre-exposing worms to a known neuroprotective compound acetaminophen could suppress the effects of neurotoxin on movement.
Further, this study demonstrates that dopamine and the D2-type dopamine receptor are necessary to modulate electrotactic movements in worms. A reduction in extracellular dopamine leads to a significant increase in the swimming speed as judged by the analysis of bas-1(dopa decarboxylase) and cat-1(VMAT) mutants. The dopamine transporter dat-1 acts genetically downstream of bas-1 and cat-1 since dat-1 mutants efficiently suppress bas-1 and cat-1 phenotypes. We also found that DOP-3(D2-type receptor) acts as the sole receptor for dopamine-mediated regulation of electrotaxis. Interestingly, we found that prolonged exposure to EF resulted in a gradual decline in the swimming speed such that animals were 40% slower at the end of ten minutes exercise period. This change is mediated by DOP-3 since dop-3 mutants continue to swim at the initial speed and don’t slow down. This conclusion is supported by the analysis of animals treated with Heloperidol(D2 antagonist) and SKF38393(D1 agonist). Overall, our work demonstrates that D2 receptor-mediated neuronal signalling is required to restrict muscle activity not only during the initial phase of electrotaxis swimming but also for the entire duration of the assay. We suggest that such a role of dopamine signalling might serve as an important and conserved mechanism to limit muscle overuse during prolonged physical exercise.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Yarmouth Township: A Study in Land Utilization

subject:
Yarmouth Township
land utilization
physical geography

abstract:
An abstract is not provided.
Thesis
Bachelor of Arts (BA)


title: Land/ Sea Breeze Circulation Systems of Churchill, Manitoba

contributor:
Rouse, W. R.
Geography

subject:
Churchill
Manitoba
land breeze
sea breeze
wind direction
temperature
vapour pressure
climate

abstract: This research paper was submitted to the Department of Geography in fulfilment of the requirements of Geography 4C6.

abstract: This research details the presence of the land/ sea breeze circulation system near Churchill, Manitoba. Data collected from June 6 to August 13, 1987 were analyzed with respect to wind direction, temperature and vapour pressure to determine the effects of the system on the climate. Results indicate that there is a seasonal progression in wind frequency from dominantly onshore (42% of the time) to dominantly mixed winds (75% of the time). The frequency of the land/ sea breeze increases across the season. Smaller wind velocities, colder temperatures and larger vapour pressures are associated with onshore winds, while offshore winds have greater velocities, higher temperatures, and smaller vapour pressures. Offshore winds are 5-7°C warmer than onshore winds. The sea breeze is larger than the land breeze by a 3:2 ratio.

abstract: Thesis

abstract: Bachelor of Arts (BA)


title: Studies with Sector-Type Mass Spectrometers

contributor:
Thode, H. G.
Chemistry

subject:
mass spectrometer
McMaster University
deuterium

abstract: The uploaded file contains both Part 1 and Part 2 of the work.

abstract: An abstract is not provided.

abstract: Thesis

abstract: Master of Science (MSc)


title: Altair 680b Cross-Assembler

contributor:
Kennet, T. J.
Computation

subject:
Altair 680b Cross-Assembler
Nova Assembly Language
microcomputer
computer language

abstract: The Altair 680b Cross-Assembler is a program written in the Nova Assembly Language. It can be used to assemble Altair 680b assembly language programs. The object code can be punched on paper-tape for execution on the Altair 680b microcomputer. This report describes the design and working of the Cross-Assembler. A program listing and a few sample runs are also included.

abstract: Thesis

abstract: Master of Science (MSc)


title: Contact Chemoreception in Haematophagous Tabanids: A Study of the Distribution and Structure of Tarsal and Labellar Taste Receptors and Their Sensitivity to Sugars and Other Chemicals

contributor:
Davies, Douglas M.
Biology

subject:
tabanid
tarsal
labella
trichode
proboscis
contact chemoreceptor
flies

abstract:
A study of the tarsi and mouthparts of females in three representative genera of tabanids revealed that the ventro-lateral surface of the fore-tarsi and the aboral margin of the labella were the principal loci of contact chemical sensilla. Of the four main types of aboral labellar trichodes (A,B,C and D), two (B and C) proved to be gustatory and then only at the tip. Two other types of trichodes (E and F) were identified on the anterior aspect of the labella. These were different from the aboral setae (type A,B,C, and D) in shape, size and function.

Extension of the proboscis was taken as the index of positive tarsal stimulation and the criterion of positive labellar stimulation was the spreading of the labellar lobes in an extended proboscis. This was observed to be the same in free as well as attached experimental flies. Newly emerged females showed similar response.

The frequency method generally employed in psycho-physical studies for estimating thresholds in mammals was successfully extended to tabanids. Using this method the stimulative effectiveness and threshold of various sugars for the tarsal and labellar taste sensilla was determined. Comparison was made between the frequency method and the ascending method of estimating thresholds with regard to sucrose. The effect of starvation on responsiveness of tarsal and labellar contact chemoreceptors was determined. Newly emerged flies became increasingly sensitive to sucrose during the duration of tests when they were strictly maintained on water diet.

Intergenerlc differences and similarities were seen in the behaviour immediately before feeding. The flies fed on "dry" sucrose as well as on solutions of appropriate concentrations. By analysing the crop contents of wild-caught tabanids, it was established that they fed on sugars and these findings were related to tabanid feeding behaviour and adaptation in nature.

Using whole blood, sugars and blood-sugar mixtures at various concentrations and proportions (in the case of blood-sugar mixtures), their dispatch to crop and/or mid-gut was studied. In addition, select group of amino acids and nucleotides were also tested to determine if these acted as feeding stimulants for the deer-flies.

Wild-caught females of deer-flies lived on dry sucrose and water and on 1.OH glucose solution longer than on distilled water alone or without food and water.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: PATIENT AND INFORMAL CAREGIVER ENGAGEMENT IN DESIGNING A HEART FAILURE ONLINE APPLICATION (HFAPP) TO PROMOTE SELF-CARE IN THE HOME SETTING FOR OLDER ADULTS

title: END USER ENGAGEMENT IN DEVELOPING A SELF-CARE ONLINE APP

contributor:
Demers, Catherine
Archer, Norm
Valaitis, Ruta
eHealth

subject: eHealth, Heart Failure, Self-care

abstract:
Approximately half a million people in Canada suffer from heart failure (HF), a leading cause of hospital admission. HF outcomes can be improved by self-care behaviors, to which patients often show low adherence. This study focuses on the co-design of an online self-care application and community intervention, called HFApp, which patients with HF and their informal caregivers could use to potentially improve HF outcomes.
 	The intended users for HFApp are older adults with HF and their informal caregivers. The primary objective of this study is to identify themes for the development of HFApp. The secondary objective is to apply these findings to identify user needs and preferences for HFApp.
	Persona-scenario discussion sessions were conducted with 4 older patients with HF (≥ 60 years) and 4 informal caregivers from the Hamilton Health Sciences Heart Function Clinic. One persona-scenario discussion session was held for each participant type (i.e. patients with HF or informal caregivers). Participants were divided into pairs and participant pairs created personas and scenarios together. Scenarios included: (1) how they learn about HFApp, (2) how they might access HFApp, (3) where they are when they use HFApp, (4) who might help them with HFApp, and (5) how often they use HFApp. All discussions were audio recorded.
	Data analysis, using NVivo 10 , provided six categories of design themes which were used to develop a list of user requirements for HFApp. Some of these requirements help users perceive HFApp to be more useful and give a sense of self-care confidence. However, some requirements may be excluded due to low feasibility. It is recommended that a larger persona-scenario group session be conducted in the future to support the requirements gathered in this study as well as identify any new requirements.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Approximately half a million Canadians suffer from heart failure (HF), a leading cause of hospitalization. This study focuses on the involvement of potential users in the design of HFApp, an online HF self-care application (“app”). These users include older patients with HF and their family and close friends. One of HFApp’s objectives is to potentially decrease hospital visits for older patients with HF. A design based on patient preferences called persona-scenarios was used to conduct this study. Participants were asked to create pretend individuals that were similar to themselves and describe scenarios in which these individuals would interact with HFApp. These could include: (1) how they learn about HFApp, (2) how they might access HFApp, (3) where they are when using HFApp, (4) who might help them with HFApp, and (5) how often they use HFApp. These interactions will be used to identify user requirements and preferences for HFApp’s design.


title: Energy Efficient Offloading for Competing Users on a Shared Communication Channel

contributor:
Todd, Terence D.
Karakostas, George
Electrical and Computer Engineering

subject:
Mobile cloud computing
Computation offloading
Game theory
Nash equilibrium

abstract:
In this thesis we consider a set of mobile users that employ cloud-based computation offloading. In computation offloading, user energy consumption can be decreased by uploading and executing jobs on a
remote server, rather than processing the jobs locally. In order to execute jobs in the cloud however, the user uploads must occur over a base station channel which is shared by all of the uploading users. Since the job completion times are subject to hard deadline
constraints, this restricts the feasible set of jobs that can be remotely processed, and may constrain the users ability to reduce energy usage.  The system is modelled as a competitive game in which each user is interested in minimizing its own energy consumption. The game is subject to the real-time constraints imposed by the job execution deadlines, user specific channel bit rates, and the competition over the shared communication channel. The thesis shows that for a variety of parameters, a game where each user independently sets its offloading decisions always has a pure Nash equilibrium, and a Gauss-Seidel method for determining this equilibrium is introduced. Results are presented which illustrate that the system always converges to a Nash equilibrium using the Gauss-Seidel method. Data is also presented which show the number of Nash equilibria that are found, the number of iterations required, and the quality of the solutions. We find that the solutions perform well compared to a lower bound on total energy performance.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: An Investigation of Coloured Petri Nets:Automated Part Cutting Case Study

contributor:
Janicki, Ryszard
Computer Science

subject: petri net, coloured, alegbra, graph, automation, part cutting

abstract:
Petri nets are a graphical construction with clearly de ned semantics which can model
concurrent communicating systems in a formal manner similar to the way that automata
theory can model formal language theory(Petri, 1962). As Dr. Carl Petri
found the existing automata insu cient or too cumbersome for describing communicating
systems others have found Petri Nets to be too cumbersome for e ectively
reasoning about sophisticated, real world systems. In some cases these di culties
were overcome by extending the theory of Petri Nets. Dr. Kurt Jensen developed
the theory of Coloured Petri Nets (Jensen, 1981) for the purpose of generalizing and
simplifying complex Petri Net models. This work incorporates Coloured Petri Nets
and other theoretical extensions to describe a real world automated steel cutting system.
During the course of this investigation the paper will formalize colours in the
language of algebras and examine patterns related to timing conditions.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: Petri nets can provide a graphical explanation of computer systems that have sophisticated communications.  The graph has a precise mathematical meaning which allows it to be formally analyzed to prove many interesting properites of the net.  There have been many extensions of the theory, some of which are incorporated to this model of an automated steel cutting machine.  This thesis also presents the idea of colours, or data types, in the language of algebras.


title: Interactive properties of leukemia stem cells with their environment

contributor:
Bhatia, Mickie
Biochemistry and Biomedical Sciences

abstract:
Rare cancer stem cells are thought to be responsible for relapsed disease in many malignancies due to their preferential ability to evade cytotoxic therapy.  The hierarchical organization of cancer has been most thoroughly described in acute myeloid leukemia (AML), in which leukemia stem cells (LSCs) have been shown to both self-renew, and generate short-lived dysfunctional progeny. To date, most investigational efforts to eradicate these cells have focused on their intrinsic attributes. However, stem cell identities in the normal hematopoietic system are uniquely maintained through associations with the microenvironment. Similar context-dependent behaviour may also apply to malignant stem cells, although this has not been well explored in AML. Therefore, I hypothesized that AML-LSCs are sensitive to the conditions of their external environment, and that these influences can be used to both understand chemotherapy resistance mechanisms, and to devise novel therapeutic strategies.
We began by providing evidence that LSCs cannot be distinguished from healthy hematopoietic stem cells (HSCs) based on a signaling pathway that has been clinically shown to have therapeutic promise in AML. Instead, we showed that non-hematopoietic cells in the bone marrow (BM) are more sensitive to these signals, which may impact neighbouring LSCs in a non-cell-autonomous manner.  We then investigated whether LSCs interact with abnormal “niches” in BM, using sophisticated xenograft modeling. Based on in situ tissue analysis and in vivo functional assays, we found that LSCs directly compete with healthy HSCs for shared niche occupancy in BM, and equally require niche support to sustain their self-renewal. Furthermore, this dependence could be exploited by cytokine dissociation of LSC-niche interactions during transplantation therapy, to promote competitive replacement by healthy HSCs.
Finally, we investigated the in vivo cellular events that lead to leukemic relapse after chemotherapy, a process thought to occur due to niche-mediated protection of quiescent LSCs. Our findings however challenge the conventional view that LSCs are preferentially spared by cytotoxic therapy. While primitive leukemic cells are initially suppressed following chemotherapy, we show that a unique population assembles to regenerate the disease at a rate disproportionate to healthy recovery. Focusing on these cells, we have described novel molecular hallmarks of leukemic regeneration, and demonstrated that they can be targeted in combination with chemotherapy to durably suppress leukemic growth. Collectively, the data presented within this thesis offer a broader conceptualization of LSCs as interactive components of the BM environment. This has revealed novel therapeutic paths to ultimately enable LSC targeting on multiple fronts.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)