title: Industrial Extended Multi-Scale Principle Components Analysis for Fault Detection and Diagnosis of Car Alternators and Starters

contributor:
Habibi, Saeid
Ziada, Samir
Mechanical Engineering

subject:
EMSPCA
Wavelets
PCA
signal processing
fault detection & diagnosis
industrial

abstract:
Quality assurance of electrical components of cars such as alternators and starters is
an important consideration due to both commercial and safety reasons. The focus of
this research is to develop a complete Fault Detection and Diagnosis (FDD) solution
for alternators and starters for their implementation in test cells. The FDD would
enable more reliable testing of production line parts without compromising high production
throughput. Our proposed solution includes three elements: (1) background
noise elimination; (2) fault detection and analysis; and (3) fault classi cation for fault
type identi cation.
Noise gating, Extended Multi-Scale Principle Component Analysis (EMSPCA),
and Logistic Discriminant classi er were used to perform these three elements. The
FDD strategy detects and extracts fault signatures from multiple sensors (which are
vibration and sound measurements in this research). Included in this strategy is
 ltering of the background noise in sound measurements to enable operation and
maintain FDD performance in noisy conditions. The EMSPCA is the core of the
FDD strategy. EMSPCA breaks the fault into time-frequency scales using wavelets
and applies Principle Component Analysis (PCA) on each scale. This reveals the
signature of the fault. The fault signature is then examined by a classi er to match it
with the correct type of faults. The total FDD strategy is automated and no operator
intervention is required.
The advantages of the proposed FDD strategy are: (1) high accuracy in detection
and diagnosis; (2) robustness in noisy industrial conditions; and (3) no need for operators'
intervention. These advantages make the proposed FDD strategy a promising
candidate for mass industrial applications.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Prediction and Prevention of the Progressive Degradation of Mining Screens using Wireless Vibration Analysis Tools

contributor:
Mohrenschildt, Martin
Software Engineering

abstract:
Vibration analysis (VA) is an extremely valuable technology which has been around for decades but its application and deployment techniques continue to grow. In 2006 W.S. Tyler, an industrial screening company, approached the McMaster Computing and Software department in search of a VA strategy to be used in their industry. The massive screens they produce vibrate with incredible speed and force to sort various types of materials. Over the years this department has developed a successful wireless vibration analysis tool along with software to perform analysis.
The current VA tool can be used to tune the screen during commissioning as well as aid in troubleshooting during or after a failure. The next evolutionary step in the advancement of the system would be to perform condition monitoring.
Predictive maintenance is a relatively new concept whereby an impending machine fault or failure is detected through condition monitoring and is corrected before it occurs. Predictive maintenance is immensely beneficial and will be discussed.
The focus of this thesis is on improvements to the VA system adding longer-term, progressive data collection and analysis abilities to the current tool-set.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: KAISO: A NOVEL MEDIATOR OF INTESTINAL INFLAMMATION AND TUMORIGENESIS

contributor:
Daniel, Juliet
Biology

subject: Kaiso intestine hypoxia tumorigenesis Apc methylation

abstract:
Multiple studies have implicated the POZ-ZF and methyl-DNA-binding transcription factor, Kaiso, in the regulation of genes and pathways that are important for development and tumorigenesis. In Xenopus embryos and mammalian cultured cells, Kaiso has been implicated as a negative regulator of the canonical Wnt signaling pathway. Paradoxically however, Kaiso depletion extends lifespan and delays polyp onset in the ApcMin/+ mouse model of intestinal tumorigenesis, where aberrant activation of Wnt signaling results in the development of neoplasias. These findings call into question Kaiso’s role as a negative regulator of canonical Wnt signaling and led us to hypothesize that Kaiso promotes intestinal tumorigenesis by a mechanism independent of its role in canonical Wnt signaling.
To further delineate Kaiso’s role in intestinal tumorigenesis and to determine Kaiso’s role in regulating canonical Wnt signaling in the murine intestine, we generated a Kaiso transgenic mouse model expressing an intestine-specific murine Kaiso transgene. We then crossed our Kaiso transgenic mice with ApcMin/+ mice and analyzed the resultant progeny. Unexpectedly, Kaiso transgenic mice exhibited intestinal inflammation, increased expression of Wnt target genes and deregulated progenitor cell differentiation, although ectopic expression of Kaiso was not sufficient to drive tumorigenesis in the intestine. In agreement with previous studies, ectopic Kaiso expression in ApcMin/+ mice resulted in a significantly shortened lifespan and increased tumour burden. While we were unable to determine the precise mechanism by which Kaiso promotes intestinal tumour development, we found that Kaiso-induced inflammation is enhanced in the ApcMin/+ background and ectopic Kaiso expression further intensifies Wnt target gene expression in this model.
Collectively, these studies have identified novel roles for Kaiso in regulating inflammation and cell-fate determination in the intestine. Furthermore, our findings suggest that Kaiso may contribute to intestinal tumorigenesis by promoting inflammation, which has been shown to be a predisposing factor for colorectal cancer development. Lastly, we have demonstrated distinct tissue and organism-specific roles for Kaiso in regulating canonical Wnt signaling.
While, the aforementioned studies were the primary focus of this thesis, we also examined Kaiso’s role in DNA methylation-dependent repression of two tumour-associated genes, cyclinD1 and HIF1A. Our studies revealed that Kaiso binds and regulates the cyclinD1 locus via both sequence-specific and methylation-dependent DNA binding, suggesting that these alternate modes by which Kaiso binds to DNA may not be mutually exclusive. Furthermore, we identified a previously unexplored role for Kaiso in regulating the expression of the master regulator of hypoxia, HIF1A, which implicates Kaiso in modulating hypoxia-driven tumorigenic processes.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Territorialized Cosmopolitanism: Space, Place and Cosmopolitan Identity

title: Territoralized Cosmopolitanism

contributor:
O'Brien, Susan
English and Cultural Studies

subject:
Postcolonial
Narrative fiction
cosmopolitan
liberal-bougeois

abstract:
 This dissertation examines postcolonial narrative fiction as a site of cosmopolitanism that is self-consciously local and global at the same time. I argue that, in order to think through a form of cosmopolitanism that takes seriously questions of social justice, we must think through the way cosmopolitan world-views are articulated in place. Much is made of the deterritorializing forces of both cosmopolitanism and globalization, but, as the novels I examine suggest, this ignores the simultaneous re- and multi-territorialization that is always ongoing. This gap in cosmopolitan theory means that everyday lived cosmopolitanism, which enacts this oscillation between the global and the local, is often left outside the scope of theory. Fiction offers a corrective to cosmopolitan theory by paying particular attention to that which is often outside of the scope of this theoretical paradigm. Postcolonial theory's emphasis on the importance of political responsibility and the remembrance of past and ongoing violence informs this project.

 In this dissertation, I primarily engage with the two dominating strains of cosmopolitan theory: liberal-bourgeois cosmopolitanism and vernacular cosmopolitanism. I read these theoretical models alongside cultural geography and eco-criticism to account for what I term "territorialized cosmopolitanism." I suggest that territorialized cosmopolitanism enacts a dialectical movement between the global and the local and this movement between these two zones prompts ethical and political responsibilities to others (both human and nonhuman) both physically nearby and distant - reflecting the shaping role place defined in physical and cultural terms-- has in developing cosmopolitanism.

 Focussing my reading on novels that address cosmopolitanism through different kinds of places (the metropolis, the regional city, and the rural community), I argue that different places focus a territorialized cosmopolitan sensibility in different ways. What these differences suggest is the importance of un-learning typical notions of how place is used and represented - particularly in relation to the global. A territorialized cosmopolitan sensibility, in these novels, allows for and encourages this unlearning.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Spatial Distribution and Mobility of the Ran and the Bicoid proteins in Live Systems

contributor:
Fradin, Cecile
Physics and Astronomy

subject:
biophysics
HeLa cells
dynamical mechanisms

abstract:
To the reader
<p> Since I worked on two separate projects towards my doctorate thesis, the arrangement of my thesis is rather unusual. The reader will find that my thesis is divided into four parts. Part 1 is dedicated to a very general introduction about the basic knowledge needed to guide you, the reader, through the rest of the thesis. Within this part, different sections focus on different fundamental aspects of Biophysics related to my work. In Part 2, I discuss my studies of the distribution and dynamics of the nuclear protein Ran in live interphase HeLa cells. This part contains a background section specific to this project, the materials and methods used for this study, experimental results, a discussion of our findings, and it ends with conclusions. Part 3 is dedicated to the study of the dynamical mechanisms responsible for the establishment of the Bed protein concentration gradient along the anterior-posterior axis in live Drosophila melanogaster embryos. Again, a specific background section is included in this part, followed by the materials and methods used to perform this research, results, discussions and finally I will summarize my results to conclude this work. The last part, part 4, is rather short and contains the summary of the overall results of my work on both nuclear proteins with some emphasis on the similarities and differences in their dynamical behavior.</p>

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: The Internal Skeletal Geochemistry of Some Modern and Ancient Cephalopods

contributor:
Gröcke, D.
Geography and Earth Sciences

subject: geochemistry Sepia Belemnoidea cuttlebones isotopes

abstract:
 This dissertation explores the internal geochemistry of Sepia officinalis cuttlebones and the rostra of several genera of extinct Belemnoidea with the aim of improving our ability to reconstruct the palaeoclimatic record. Sepia share several unique morphological features with Belemnoidea and may be their most suitable modern analogue. Consequently, a geochemical comparison between the internal skeleton of Sepia and Belemnoidea may help improve the understanding of the geochemistry of Belemnoidea rostra, which are often used to investigate Mesozoic palaeoenvironmental conditions.

 High resolution sampling of oxygen isotope values from five S. officinalis cuttlebones from the English Channel confirmed that S. officinalis cuttlebones provide an accurate record of water temperature that preserves seasonal temperature variation consistent with sea surface temperature records. Carbon isotope values show increasing values with growth until a sharp decline late in life, documenting a decrease in metabolism with ontogeny, followed by a late life increase. Trace element concentrations measured from two of these cuttlebones document a small but statistically significant correlation between oxygen isotope values and both Sr and Mn concentration, suggesting some degree of temperature control on their rate of incorporation. Mg concentration exhibits a small but statistically significant correlation with carbon isotope values, suggesting metabolism may exert some control on the rate of Mg incorporation.

 Due to the process of fossilisation, diagenesis may alter the geochemistry of Belemnoidea rostra, which is difficult to detect using stable isotope values alone. It is necessary to detect samples that have diagenetic overprinting of the original environmental signal so that past geochemical relationships may be accurately reconstructed. As Mn and Sr are enriched and depleted (respectively) in diagenetic fluids, they may be used as indicators of alteration. Following the removal of diagenetically altered samples, the carbon isotope values of Belemnoidea rostra sampled from the Green Beds at Carbondale River, Alberta, Canada document a statistically significant increase with ontogeny, suggesting a decrease in metabolic rate similar to S. officinalis. Contrasting with S. officinalis, oxygen isotope values do not show seasonal palaeotemperature cycles, possibly the result of latitudinal migration with favourable water temperatures. Trace element concentrations of Mg exhibit a small but statistically significant correlation with Belemnoidea oxygen isotope values, contrasting with Sr and Mn in S. ofjicinalis, suggesting some temperature control on the incorporation rate of Mg in belemnoidea calcite. The ranges in oxygen isotope and Mg values were used to investigate changes in surface and deeper water palaeotemperatures during the deposition of the Green Beds. Similarly, the range in carbon isotope values within individual Green Bed Belemnoidea rostra documented a positive isotope excursion in the Green Bed section, which may become a useful geochemical marker for the region.

 In most previous studies, palaeoenvironmental conditions have been reconstructed using a single sample from unspecified locations within Belemnoidea rostra. A high resolution sampling approach is necessary to capture the range of geochemical values preserved in individual rostra and may help to minimise the effects of sample bias in the geochemical record. Sampling radially from the apical line to the outside edge of an individual Belemnoidea rostrum is permits the collection of geochemical information spanning the organism's lifespan, and will improve the interpretation of the biology and environment while minimising sample bias.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Eternal Jerusalem: Jerusalem/Zion in Biblical Theology with Special Attention to "New Jerusalem" as the Name for the Final State in Revelation 21-22.

contributor:
Porter, Stanley E.
Boda, Mark J.
Christian Theology

subject:
New Jerusalem
Revelation
God
humanity
New Testament
Old Testament

abstract:
The thesis of this dissertation is that the picture of the New Jerusalem in Revelation draws upon
antecedent Jerusalem/Zion theology to provide a meaningful depiction of the final state of believers in
Jesus as both communion with God and life as a community.
 This biblical theological study uses a canonical approach that includes an examination of extra-biblical Second Temple literature as an aid to accessing NT understandings of OT texts. Previous studies of Jerusalem do not cover the entire canon, focus on historical or literary issues rather than theology, or access only OT texts clearly alluded to in Rev 21-22 rather than the entire theological tradition about Jerusalem, which culminates in the "New" Jerusalem

 The Pentateuch foresees Jerusalem's role as place of contact between God and Israel. In the Historical Books, David completes the conquest of Canaan by taking Jerusalem and establishing YHWH's cult there. But because of the sin of the kings and people God abandons the city for a time. Jerusalem after the return from exile is still less than ideal. In the Psalms, Jerusalem is depicted as God's inviolable holy mountain. The prophets proclaim punishment for sinful Jerusalem but future restoration to the kind of ideal state described in the Psalms. Jerusalem/Zion can be seen as the ultimate goal of both the First and Second Exoduses.

 Non-canonical Second Temple literature emphasizes the pre-Davidic role of Zion as place of God's contact with humanity. The Babylonians could not have taken the city without God's co-operation, and even then, the Temple furnishings were secretly preserved. Zion's cosmic importance and eschatological role are often emphasized, with emergence of belief in a heavenly Jerusalem.

 eschatological role are often emphasized, with emergence of belief in a heavenly Jerusalem. In the New Testament, earthly Jerusalem rejects the Messiah, and so forfeits its role as link to glorious eschatological Jerusalem. Old Testament prophecies of renewal are instead fulfilled in the resurrection of Jesus, emergence of the church, and ultimately the New Jerusalem.

 of deep intimacy with God, community among all believers, intense experience of life, and
complete eternal safety from sin and evil. This was God's plan since creation. Jerusalem as the goal and focus of God's people on their journey towards him in the Old Testament foreshadows the New Jerusalem as their destination at the end of the age.

 The dissertation closes with suggestions for practical application and further study.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Non-deterministic Analysis and Differential Equations

contributor:
Lints, R.G.
Mathematics

subject:
anti-differential type
g-differential
equations
derrivates
Euclidean spaces

abstract:
 Several results are given showing under what
conditions one may solve an anti-differentiation type g-differential equation. Also the correspondence between usual derivatives and derivatives is examined for the case of Euclidean spaces. In addition a survey of Non-deterministic Analysis is given.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Effect of Aperture Variability, Specific Discharge, and Ionic Strength on Colloid Transport in Single Fractures

contributor:
Dickson, Sarah E.
Guo, Yiping
Civil Engineering

subject: effect, aperture variability, discharge, colloid transport, single fractures

abstract:
An improved understanding of colloid transport in fractured media is required to assess the potential for microorganisms to contaminate groundwater, to develop groundwater management/protection plans, to design remedial action strategies based on the application of microorganisms, and to quantify colloid-facilitated transport of many organic and inorganic contaminants. Although colloid transport has been investigated to
an extent in porous media environments, this field is still in its infancy in fractured media environments.

Colloid transport in fractured media involves a host of complex and interacting processes, including (among others): advection, hydrodynamic dispersion, attachment and
detachment, straining, size/ charge exclusion, and gravitational settling. These processes are, in turn, influenced by the physicochemical properties of fractured media, the geochemical properties of groundwater, hydrodynamics, and the colloid properties. This research program focused on investigating the effects of aperture field variability, specific discharge, and ionic strength on colloid transport in saturated, variable-aperture, single fractures. An extensive literature review was first conducted, and a combination of
physical model experiments and numerical simulations were then employed to achieve this goal.

 Three transparent fracture replicas were fabricated, and the light transmission method was employed to obtain a direct measurement of each of the three aperture fields. A systematic series of hydraulic and tracer tests was conducted on each of the three experimental fractures, and the cubic law, mass balance and frictional loss apertures were
calculated. Additionally, the experimental breakthrough curves were fit to the one-dimensional advection-dispersion equation. The results clearly demonstrate that the mass balance aperture is the only appropriate 'equivalent aperture' for describing transport in a single variable-aperture fracture, and that the mass balance aperture is an excellent
approximation ofthe arithmetic mean aperture.

A 3^3 factorial experimental design was then implemented to numerically investigate the
interactive effect of the arithmetic mean (μb), standard deviation (σb), and anisotropic ratio (AR=λ^b x/ λ^b,y where λ^b x and λ^b y is the correlation length of the aperture field along x- and y- direction respectively) of single fracture apertures on dispersion regimes (specifically Taylor dispersion and geometric dispersion) and dispersivity. The simulation results show that: (1) for a fixed hydraulic gradient: (a) the dominant dispersion regime is
controlled by μb, and to a lesser degree, σb, and (b) geometric dispersion becomes more dominant as the coefficient of variation (CoV = σb/μb) increases; (2) for a fixed mean aperture, the dispersivity and the spread in dispersivity for varying ARs increase with the CoV; and (3) the AR has a significant effect on dispersivity only when the CoV is large (>0.2).

 Numerical simulations investigating colloid and solute transport in single parallel-plate fractures, conducted using the Random Walk Particle Tracking (RWPT) method, demonstrated that: 1) There exists a threshold value, δo , of the aspect ratio, δ (δ= 2rc/b, where rc and b represent the colloid radius and fracture aperture respectively), where the average transport velocities of colloids and solutes are similar. When δ> δo , the Taylor Aris assumption is satisfied, and tp (tp = tc/ts, where tc and ts represent colloid and solute
retention times respectively) decreases as δ increases, as is well documented in the hydrodynamic chromatography literature. However, when δ < δo , the Taylor-Aris assumption is violated, and tp increases as δ increases. This has never been documented before, and it helps to explain some seemingly contradictory work in the literature. 2) The Taylor dispersion coefficient and its extension by James and Chrysikopoulos (2003) will overestimate the colloid dispersion coefficient significantly when the Taylor-Aris assumption is violated. Additionally, these simulations demonstrated that tp and
DL,coll/DL,solute (where DL,coll and DL,solute represent the dispersion coefficients of colloids and solutes respectively) decrease with increasing CoV, and that the anisotropy ratio, AR, only plays a minor role on these two ratios compared to the CoV. These observations have never been documented before to the knowledge of these authors, and have important implications towards the interpretation of colloid transport in both porous and
fractured media.

 A combination of physical experiments, numerical simulations and visualization techniques was employed to investigate the impact of aperture variability, specific discharge, and ionic strength on colloid transport processes. The mean colloid transport velocity and colloid dispersion coefficient were obtained by fitting the analytical solution of the one-dimensional advection-dispersion equation (ADE) to the measured breakthrough curves. Two significant observations were made from the colloid transport experiment images: (1) colloids migrate along preferential pathways, and bypass some aperture regions; and (2) the colloid plume is irregular in shape, and becomes more irregular with increasing specific discharge, indicating non-Fickian transport. It is therefore postulated that the dispersivity cannot be completely determined by the aperture field characteristics alone; it is also a function of specific discharge. The colloid recovery in all fractures was found to increase with increasing specific discharge. For each specific discharge, it was found that the colloid recoveries in F2 and F3 were similar, and were always larger than the recovery in F1. This is consistent with the fact that the arithmetic mean apertures of F2 and F3 were similar (μb,F2= 1.57 mm, /μb,F3= 1.75 mm), and larger
than that of F1 (μb,F1 = 0.88 mm). This suggests that it is the transport step (the step in which the colloids are transported from the bulk fluid to the vicinity of the fracture wall), and not the attachment step, that plays the dominant role in the colloid sorption process. It was also found that the mean transport velocity and dispersion coefficient of colloids are larger than those of solutes in F3 (CoV = 0.29), but similar to those of solutes in F1
(CoV = 0.78) and F2 (CoV = 0.71). This confirms the numerical simulation results from this work indicating that tp and DL,coll/DL,solute decrease with increasing CoV. These findings have significant implications on the interpretation of colloid transport data.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Packet Transmission Scheduling for Supporting Real-Time Traffic in Wireless Mesh Networks

contributor:
Zhao, Dongmei
Electrical and Computer Engineering

subject: packet transmission, Quality of service, real-time traffic, mesh acces point,

abstract:
Packet transmission scheduling plays a key role in Quality of Service (QoS) support for real-time traffic and efficient radio resource utilization in a wireless mesh network (WMN). It is a highly complicated problem due to the fact that any scheduling decision at one mesh access point (AP) may affect the scheduling decisions in the entire network. The strict delay requirement of real-time applications makes the scheduling problem even more challenging.

 In this thesis, the packet transmission scheduling problem for real-time constant-bit-rate (CBR) traffic in a WMN is first formulated as a standard integer linear programming problem, which takes into consideration both the multihop packet transmission delay and timeline coordinations of the mesh APs. The objective is to efficiently utilize the radio resources, subject to available bandwidth of the mesh APs, co-channel interference, and packet transmission latency requirement.

Two heuristic schemes, namely AP-based scheduling (ABS) and connection-based scheduling (CBS) schemes, are then proposed to support real-time CBR traffic. ABS makes scheduling decisions on a per-AP basis. Scheduling decisions at APs with a higher traffic load are determined before those at APs with a lower traffic load. ABS achieves close-to-optimum capacity but may go through multiple iterations before reaching a feasible solution. CBS makes scheduling decisions on a connection-by-connection basis. It gives a higher priority to connections with more hops. In CBS, connections with a lower priority can only use resources remaining from serving all higher priority connections. CBS requires much lower complexity than ABS while
achieving capacity performance slightly lower than ABS.

We extend the proposed ABS and CBS scheduling schemes for supporting
real-time variable bit rate (VBR) traffic in a WMN. By combining the concept of
effective bandwidth and the proposed scheduling schemes, both delay and packet loss performance of the VBR traffic can be effectively satisfied. The scheduling schemes are further extended for supporting real-time traffic in a WMN with multi-radio APs.

All the scheduling decisions are done at the time when new connection requests arrive and the results are used to make admission control decisions. In this sense, the work in this thesis is for both packet transmission scheduling and admission control for real-time traffic in WMNs.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: X-Ray and Neutron Scattering Studies of Underdoped La2-xBaxCuO4 Single Crystals

contributor:
Gaulin, B.D.
Physics

subject: superconductivity, magnetism, uderdoped, x-ray, neutron, single crystals

abstract:
 The interplay between superconductivity, magnetism and crystal structure is a central issue in the study of the high Tc cuprates. The transition metal compound La2-xBaxCuO4 (LBCO) was the very first high Tc superconductor, discovered by J. G. Bednorz and K. A. Muller in 1986. However, it has been much less extensively studied than other high Tc materials, due to the difficulty of growing large single crystals. With our Image Furnace facility, we have successfully grown high quality, large LBCO crystals (with x~0.095 , 0.08, 0.05 and 0.025) on the underdoped side of the well known 1/8 (x=0.125) anomaly in this material's phase diagram.

 Using our rotating anode X-ray source at McMaster University we have
performed high-resolution X-ray diffraction studies on our x=0.095 and 0.08
samples and on a 1/8 doped LBCO (x=0.125) crystal grown by our collaborators. The X-ray study mapped out a sequence of tetragonal and orthorhombic crystal structures with temperature, which were known from earlier measurements.

We have also performed neutron scattering studies at several Laboratories on x=0.095 , 0.08, 0.05 and 0.025 samples. We observed elastic spin incommensurate Bragg peaks in all samples, and inelastic measurements on the x=0.095 sample allowed us to explore the material's low energy spin fluctuations. The elastic neutron scattering results of higher doped samples (x=0.095 and 0.08) indicate that "collinear" static incommensurate magnetic ordering develops below the low temperature structural phase transition, and this order persists into the superconducting state. Static incommensurate magnetic order is also observed in the La2-xBaxCuO4 (x=0.05 and 0.025) compounds with ordering wavevectors which are rotated by 45° about the commensurate (0.5 ,0.5 ,0) position, with respect to that in the superconducting x=0.095 and 0.08 samples. These spin modulations are one dimensional in the x=0.05 and 0.025 samples, with ordering wavevectors lying along the orthorhombic b* direction.
Such a rotation in the orientation of the static spin ordering as a
function of increasing Ba doping, from diagonal to collinear is roughly coincident with the transition from an insulating to a superconducting ground state and is similar to that observed in the related La2-xSrxCuO4 system. The
low energy, inelastic neutron scattering studies show that the dynamic spin
susceptibility for x=0.095 is constant within the superconducting state and
decreases as the temperature rises above Tc.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: A Metric Interval-based Temporal Description Logic

contributor:
Maibaum, Tom
MacCaull, Wendy
Computing and Software

subject:
Metric interval-based temporal logic
Temporal Description Logic
Tableau-based satisfiability checking
Guideline Modeling

abstract:
Because of the importance of undecidability and the concern with the high complexity of automated reasoning, a few interval-based temporal description logics (ITDLs) have been designed. Moreover, most existing ITDLs are not able to specify the lengths of intervals. In other words, they are not metric. On the other hand, some domains (e.g., medicine) are inherently interval-based, and require a metric logic in order to formalize defined processes and to check process consistency. Hence, a metric interval-based temporal description logic is required. In this thesis, we introduce such a logic (MITDL) along with two algorithms for the satisfiability checking of its formulas.
We first introduce an interval-based temporal logic, called IMPNL, inspired by Metric Propositional Neighbourhood Logic. We also present a sound, com- plete and terminating tableau-based algorithm for checking the satisfiability of IMPNL formulas. Afterwards, we combine a restricted version of IMPNL (IMPNL without a negation operator) with the ALC description logic to form a MITDL. We propose two tableau-based algorithms for checking the satisfia- bility of MITDL formulas. We show and prove they are sound, complete and terminate. These algorithms have PSpace and 2NExp-Time complexities. As a proof of concept, we use IMPNL and MITDL to model some clinical practice guidelines (CPG) and check their consistency. We compare MITDL with several languages commonly used for modeling CPGs.

abstract: Thesis

abstract: Doctor of Science  (PhD)


title: Vertical Integration, the Reconstituted State and the International Criminal Court: Expanding the Horizons of International Law and Governance

contributor:
Coleman, William D.
Political Science

subject:
International Criminal Court
global human security agenda
state sovereignty
international law

abstract:
Established in 1998, the permanent International Criminal Court (ICC) presents fundamental complexities for the concept of state sovereignty, while raising prospects for progressively developing international law and global governance in human security related areas. The Court's distinct history, negotiation and governance properties have significance well beyond international criminal justice. The ICC has broader implications for emerging forms of multilateral and transnational cooperation, the heightened standing and visibility of the individual person within the regulatory and protective precincts of international law, and the evolving role, capacity and disposition
of the state in brokering, implementing and enforcing innovative governance
arrangements. These analyses cross a number of sub-fields within international relations and global governance scholarship. A transcending dimension of my theoretical approach and intended contributions is the idea of state sovereignty as a meta-constitutive institution that fundamentally structures international law and politics, but is itself subject to subtle normative changes in its qualitative meanings and implications. As an institutional fulfillment of the post-Second World War proceedings at Nuremberg, the ICC strikingly departs from the conventional inter-national law of states. The Court seeks to uphold individual-focused human rights and humanitarian law safeguards, as reflected by the three crimes within its jurisdiction: genocide, war crimes, and crimes against humanity. Its jurisdiction over individual offenders is equally novel. The ICC is 'complementary' to national justice systems, and thus will directly administer justice only when states are demonstrably 'unwilling or unable' to conduct genuine proceedings. This distinct supranational governance format aims to facilitate national legislative and capacity-building measures to enhance the vigilance and effective functioning of domestic legal systems. The Court is the permanent organizational and normative focal point of an emerging program of enforcement and supporting efforts. More broadly, it contributes to the normative ideal and practical realization of a comprehensive and integrated global human security agenda.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Walking toward the Call of Beauty: Beauty and Affect in Badami

contributor:
Chakraborty, Chandrima
Goellnicht, Donald
Hyman, Roger
English and Cultural Studies

subject:
Anita Rau Badami
Beauty
Affect
Diaspora
Value
Ethics
Elaine Scarry

abstract: This thesis provides a reading of Anita Rau Badami’s novels The Hero’s Walk and Can You Hear the Nightbird Call? The interpretive frame constructs a theory of affect to explore the human experience of beauty through a reading of Badami’s texts. This work’s approach to beauty is derived largely from Elaine Scarry’s On Beauty and Being Just and from musings on beauty by Simone Weil. Following Weil, I understand beauty as the ascription of value or worth to various things, actions, or ideas, and I position beauty as an undergirding affective experience that is always present in the human encounter of the world. This thesis examines how Badami’s novels depict the ways in which a Weilian sense of beauty leads characters to develop affectual attachments to various ideologies and discourses represented in the diasporic landscape of the texts.  Through a critical consideration of the depicted effects of such attachments on Badami’s characters’ lives, this study also locates potential instances of what Lauren Berlant calls cruel optimism.  I contend that the novels often portray instances of cruel optimism to critique traditional practices and perspectives while ever working towards building their own pronouncement of what constitutes a more genuine, higher sense of the beautiful.

abstract: Thesis

abstract: Master of Arts (MA)


title: Journey Mapping: A New Approach for Defining Automotive Drive Cycles

contributor:
Emadi, Ali
Razavi, Saiedeh
Electrical and Computer Engineering

subject:
Automotive Drive Cycles
Hybrid and Electric Vehicles
Modeling and Simulations
Data Acquisition
Performance Prediction

abstract:
Driving has become a very common activity for most of the people around the world today. People are becoming more and more dependent on vehicles, contributing to the growth of automotive industry. New vehicles are released regularly into the market in order to meet the high demand. With the increase in demand, the importance of vehicle testing has also increased by many folds. Besides testing new vehicles for their performance prediction, existing vehicles also need to be tested in order to check their compliance to safety standards.
     Drive Cycles that have been traditionally defined as velocity over time profiles are used as vehicle testing beds. The need for re-defining drive cycles is demonstrated through the high deviations between the predicted and the actual performance values. As such, a new approach for defining automotive drive cycles, Journey Mapping, is proposed. Journey Mapping defines a drive cycle more realistically as the journey of a particular vehicle from an origin to the destination, which during its journey is influenced by various conditions such as weather, terrain, traffic, driver behavior, road , vehicle and aerodynamic.
     This concept of Journey Mapping has been implemented using AMESim for a Ford Focus Electric 2012. Journey Mapping was seen to predict its energy consumption with about 5% error; whereas, the error was about 13% when it was tested against the US06 cycle, which provided the most accurate results out of the various traditional drive cycles used for testing for the selected scope.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: EVALUATION OF SEISMIC DESIGN CRITERIA FOR ROCKING OBJECTS IN NUCLEAR FACILITIES

contributor:
El-Dakhakhni, Wael
Konstantinidis, Dimitrios
Civil Engineering

subject: rocking nuclear ASCE 43-05 FUEL CASK NEWMARK BLUME KAPUR NBK USNRC CNSC

abstract: Seismic response of free standing un-anchored objects is required to be studied in Nuclear Power Plants (NPPs) for their own integrity and potential interaction with the surrounding seismically qualified safety systems. Rocking response of a rigid body subject to seismic excitation is not very well covered in the nuclear standards except for an approximate method given in ASCE 43-05 where the design basis earthquake (DBE) response spectrum for the NPPs given in the United States Nuclear Regulatory Commission (USNRC) regulatory guide 1.60 (known as NBK spectrum developed by Newmark, Blume and Kapur (1973)) is considered as seismic input. This study evaluates existing seismic design criteria for unanchored objects that are vulnerable to rocking and overturning inside nuclear power plants. The original work of Newmark et al (1973) is revisited in order to obtain the NBK spectra at unusual damping (8.4% for example), required in order to follow the ASCE 43-05 method. Eight earthquake records are selected from Newmark et al (1973) with varying Peak Ground Accelerations (PGAs) representing strong to moderate ground motions.  Rocking response of rigid bodies to various earthquakes is determined by three methods: 1. The ASCE 43-05 method utilizing the NBK spectrum, 2. The ASCE 43-05 method utilizing the response spectrum of the earthquake records, and 3. solving the equations of motion of a rigid body for the earthquake records. Rocking spectra by these three methods created for eight earthquake records are compared with one another. It is concluded that the ASCE 43-05 method provides inaccurate predictions of the response. Considering the significant level of effort required to implement the ASCE 43-05 method, its inherent contradictions, and its inconsistent conservatism in estimating the seismic demands on rocking objects, it is concluded that the results obtained by nonlinear time history analysis are more accurate, reliable and less time consuming than those by the ASCE 43-05 method. The use of nonlinear dynamic analysis is recommended to obtain the pure planar rocking response of unanchored objects in nuclear facilities.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Moving Beyond the Individual: Activity-Based Modeling of Time Use and Travel Behavior Incorporating Intra-Household Interactions

contributor:
Scott, Darren M.
Geography and Earth Sciences

subject:
travelling
activity-based travel
intra-household interactions
CHASE
GIS toolkit

abstract:
The activity-based approach to the study of travel behavior implies a shift in focus from discrete trips to activities. A fundamental tenet of this approach is that individuals, when making their own activity-travel decisions, tend to interact with other members within a household. However, most activity-based research to date has been conducted at the individual level, but not at the household level. It is now well recognized that incorporating
intra-household interactions is crucial to the development of improved activity-based models, which allow for more accurate travel demand forecasts and policy evaluations. In this context, the studies described in this dissertation have been conducted to explore several critical issues that have remained largely neglected in past studies. One such issue is the identification of joint participation in activity and travel episodes, due to the fact that most activity-travel surveys have failed to collect information on involved persons. In this dissertation, an integrated spatio-temporal GIS toolkit is initially
developed to automatically identify and visualize (3D) joint activity/travel episodes. Such identification makes it possible to uniquely and directly incorporate intra-household interactions into studies of activity/travel behavior. The research described in this dissertation utilizes the 2003 CHASE (Computerized Household Activity Scheduling Elicitor) survey collected in the Greater Toronto Area. Several aspects of activity/travel behavior are investigated.. First, quantitative models are developed and estimated for investigating household activity time use patterns while capturing intra-household interactions. Second, the dynamics of household time use patterns are explored through descriptive analysis and structural equations models. Finally, the household activity decision-making process is further delved into with a focus on the planning priority of joint activities. Overall, the research presented in this dissertation makes important contributions to activity-based time use and travel behavior research: (1) technically, the developed GIS toolkit is helpful to reduce costs of processing large activity-travel datasets; and (2) theoretically, the empirical results presented will form the basis toward the development and implementation of an improved activity-based model.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Essays on Health and Retirement in Canada

contributor:
Veall, Michael
Economics

subject: health and retirement

subject: socio-economic status

subject: stress

subject: self-assessed health status

subject: true morbidity and mortality

subject: post-retirement health

abstract:
My dissertation is composed of an introductory chapter followed by three
independent chapters focusing on two themes: health and retirement. The last chapter concludes. After the introductory chapter, the second chapter investigates whether self reported general stress is a mediator in the relationship between socio-economic status (SES) and health. I use a six-year long panel of the Canadian Survey of Labour and Income Dynamics and employ dynamic econometric modelling techniques to study men and women who are major income earners in their families. I find little evidence that
general stress is a pathway from SES to health. While the results suggest a strong negative association between stress and health for both men and women, they provide little support to the hypothesis of a significant effect of income on stress, consistent with the direction of the SES-health gradient.
The third chapter studies whether self-assessed health status (SAH) contains
information about future mortality and morbidity, beyond the information that is contained in standard "observable" characteristics of individuals (including pre-existing diagnosed medical conditions). Using a ten-year span of the Canadian National Population Health Survey, we find evidence that SAH does contain private information for future mortality and morbidity. Moreover, the extra information in SAH is greater at older ages. Our results suggest that a shift from defined benefit to defined contribution pension arrangements may carry with it the cost of exacerbated adverse selection in the market for annuities, especially at older ages. That would make it more difficult for older
individuals to insure longevity risk. The fourth chapter looks at whether differences in early retirement pathways are associated with differences in post-retirement outcomes of health, stress and dwelling tenure. I use a 5 ample of men from the Canadian Survey of Labour and Income Dynamics, years 1996 to 2004. I find that differences in pre-retirement health indicators
(such as self-assessed health and disability), as pathways to early retirement, are likely to be associated with differences in post-retirement health and stress. In addition, the results suggest that "involuntary" retirees (men who may have retired because of health and/or health related coniitions) are more likely to experience worse post-retirement outcomes (in terms of health and stress) than men who retire "voluntarily". Retirement circumstances are found to have no statistically significant effect on dwelling tenure.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Multiparameter Sensitivity of Linear Time-invariant Networks

contributor:
Haykim, S.S.
Electrical Engineering

subject:
inductorless filters
RC-gyrator structures
sensitivity criteria
optimum tolerance test

abstract:
 The realization of inductorless filters by means of RC-gyrator
structures has been investigated, and the sensitivity of their response characteristics with respect to supply voltage variations has been measured. A critical appraisal is made of the various multiparameter sensitivity functions which have already been proposed in the literature, and the methods by which these sensitivity criteria may be computed are surveyed. A new index of performance, by which the multiparameter sensitivity of a linear, time-invariant network may be evaluated, is proposed. Furthermore, a new method of computing sensitivity indices is described and is shown to be highly efficient from a computational point of view. The index has been used to investigate the sensitivity performance of a wide range of passive and active filter structures. It has also been used to generate a so called "optimum tolerance set" for the elements of such filters and the effect of employing these optimum tolerance sets has been investigated.

 The index of perfonnance and the concept of the optimum tolerance set is extended to the case of RC active filters. A "two-level" optimization procedure is proposed, whereby an optimum nominal element value set may be combined with the corresponding optimum tolerance set to obtain a marked improvement in the sensitivity performance of the network. Finally, the synthesis of a highly selective RC-active filter is considered, and it is shown how an optimal structure and tolerance set can be obtained for such a network.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Shear thinning silicone-PEG block copolymers

contributor:
Brook, Michael A.
Chemistry and Chemical Biology

subject: Silicone, PEG, Block copolymers

abstract:
In this work, we created shear thinning block copolymers that could be potentially utilized as an artificial vitreous replacement. The materials were created using poly(ethylene glycol) (PEG) and silicone polymers, respectively, due to their high biocompatibility. Both the ABA and BAB geometry triblock copolymers were created and were characterized using parallel plate and cone-and plate rheometers. It was observed that the materials from both geometries exhibited a decrease in viscosity with increasing shear rates, thus fulfilling the criteria of being a shear thinning material.
	The materials were also characterized under different aqueous conditions. It was observed that the materials with a higher PEG composition were better able to retain their physical structure – did not disperse into aqueous solutions – at higher water content levels. The materials that retained their structure were also shown to retain their shear thinning properties.
	In the absence of solvent, the opacity of the materials increased with increasing PEG composition ratio per copolymer chain. When exposed to different aqueous conditions, the opacity of the materials was found to decrease at specific water concentrations. Materials with larger PEG blocks required a greater water content to exhibit optimal light transmission.

abstract: Thesis

abstract: Master of Science (MSc)


title: Corrosion Performance of MIG Welded Cu-lean AA7xxx Alloys

contributor:
Kish, Joseph R.
Materials Science and Engineering

subject: Aluminum Weld Corrosion AA7xxx Lap-joint T-joint

abstract:
An investigation was undertaken to better understand the corrosion behaviour of dissimilar welded Cu-lean AA7003 and AA7108 extrusions. The major variables under study were the heat-treated condition (as-welded T6 vs. as-welded T6+Paint Bake (PB)), extrusion alloy Cu composition (AA7003 vs. AA7108), weld filler composition (ER4043 vs. ER5356), weld joint geometry (lap-joint vs. T-joint), and weld direction with respect to extrusion direction (parallel  (═) vs. perpendicular (┴)). The corrosion behaviour of the various weld configurations under investigation was observed using an ASTM standard practice for modified salt spray testing (ASTM G85-A2), a GM worldwide engineering standard for cyclic corrosion testing (GMW-14872), and potentiodynamic polarization measurements. The effect of exposure to GMW-14872 on the tensile-shear behaviour of the various weld configurations under study was also investigated using a custom tensile jig.
	Examination post exposure to ASMT G85-A2 revealed the presence of differing pitting corrosion morphologies between AA7003 and AA7108. Due to increased Cu-content, AA7003 displayed deep pitting corrosion which penetrated the entirety of the dynamically recrystallized top surface layer and reached the fine-grained interior. Shallow pitting of the recrystallized surface layer was observed on AA7108, with very few penetration sites that reached the underlying fine-grained interior.
No difference in corrosion behaviour was observed between the heat affected zone (HAZ) and unaffected base alloy of welded AA7003 and AA7108, also consistent with potentiodynamic polarization results. However, the HAZ displayed dual corrosion bands separated by a thin band of unattacked alloy; a result of distinct local microstructural changes induced by thermal cycling from welding.
	Tensile-shear testing revealed four types of observed fracture modes: shear across the weld throat, fracture along the AA7xxx/ER5356 interface, fracture along the AA6063/ER5356 interface and fracture in the HAZ of AA7xxx. Little to no corrosion was observed on weld configurations exposed to GMW-14872, resulting in no differences in the tensile-shear behaviour of exposed and unexposed weld configurations. Large variations observed in the tensile-shear results were a result of numerous weld defects.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: MORPHOGENETIC AND IN VITRO STUDIES OF THE SHOOT APICES OF PHARBITIS CHOIS, STRAIN VIOLET IN RELATION TO PHOTOPERIODIC INDUCTION

abstract: pharbitis, vitro, intact, plants

abstract:
In this investigation the methods of obtaining uniform and maximum
germination of seeds and of producing contamination-free cultures of
the shoot apices of Pharbitis nil have been examined and established.

Flowering response of vegetative seedlings of different ages has been investigated as related to photoperiodic induction. The sequence of orphological changes at the shoot apex has been examined in Pharbitis
nil, in relation to an inductive photoperiod. The phenomenon of revrersion
has been investig~ted, by excising and culturing in vitro the shoot apices
from intact plants, at varying periods following inductive period. Floral induction in cultured vegetative apices has been attempted.

It is shown that the intact plants respond differently in flower formation to an inductive photoperiod. The apices vary in morphological configuration and cytologic zonation, during the germination, vegetative and reproductive stages. The in vitro studies have also shown that the flowering process once initiated, cannot be reversed until and unless a mechanism inhibits its regulatory process in the early stages of transition.
The leaf is the primary site of photoinduction. Floral induction is related to the presence of a minimum leaf area.

abstract: Thesis

abstract: Bachelor of Science (BSc)


title: CLINICAL PRACTICE AND PUBLIC HEALTH GUIDELINES: THE MAKING OF APPROPRIATE STRONG RECOMMENDATIONS WHEN THE CONFIDENCE IN EFFECT ESTIMATES IS LOW OR VERY LOW (DISCORDANT)

contributor:
Guyatt, Gordon
Health Research Methodology

subject: World Health Organization, clinical practice guidelines, public health guidelines, GRADE, discordant, strong recommendations, low confidence, low quality of evidence

abstract:
Clinical practice, public health, and policy guidelines should be developed based on a systematic approach that uses the best available evidence. The advent of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework has facilitated this, resulting in a transparent approach to guideline development.
GRADE suggests that guideline developers seldom make strong recommendations based on low or very low confidence in effect estimates (strong l/vl).
The World Health Organization (WHO) produces recommendations that guide public health policy and, in 2003, WHO adopted the GRADE approach to guideline development. Initial anecdotal evidence suggested that WHO issues a large number of strong recommendations and particularly strong l/vl.
Our research team evaluated the nature of WHO recommendations and conducted a qualitative study using interviews of guideline panel members.  Key findings included: i) WHO makes a large proportion of recommendations as strong l/vl ii) many strong l/vl are inconsistent with GRADE guidance iii) reasons guideline panel members offered for strong l/vl included skepticism about the value of making conditional recommendations; political considerations; a high confidence in benefits despite formal ratings of low confidence; and long-standing practices, funding, and policy; iv) methodologist interviewees indicated panelists’ lack of commitment to conditional recommendations; a perceived tension between methodologists and panelists due to resistance to adhering to GRADE guidance; both financial and non-financial conflicts of interest among panel members as explanations of strong l/vl; and the need for greater clarity of, and support for, the role of methodologists as co-chairs of panels.
The understanding of when and why strong l/vl are formulated at WHO is an important methodological issue that has implications not just for WHO, but for a wide range of guideline developers elsewhere.  Our findings offer insights that may guide interventions to enhance trustworthiness of practice guidelines.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Emerging Forms of Stratification in Higher Education: Comparing Canada and the United States

contributor:
Davies, Scott
Sociology

subject: postsecondary, stratification, Canadia, America, universities, structural, individual, education

abstract: This study combines longitudinal and cohort analyses to provide an extensive examination of the nature of postsecondary stratification among Canadian and American universities and students in this era of unprecedented postsecondary expansion, institutional diversification, and rising competition for external research funding. Multiple statistical methods and a range of data sources are employed to analyse new and increasingly important forms of stratification at two levels of analysis: the structural (i.e., universities) and the individual (i.e., students). At the structural level, the results demonstrate that both nations have become more stratified over time. The extent of institutional stratification and rate of growth, however, is much higher in the U.S. At the top end of the U.S. hierarchy, a few '"elite" and larger institutions appear to be winning the majority of contests for economic resources and other independent sources of revenue. In Canada, universities changed only slightly over the span of thirty years, though there is some evidence of mild convergence across nations, particularly in areas where government regulation has become more variable (e.g., endowments, tuitions). At the individual level, even though a wider variety of students from varied social backgrounds are entering into higher education, the analyses reveal a significant degree of inequality in both Canada and the United States. Consistent with existing research, gender remains an important and consistent predictor of school and field of study choices. These educational decisions were also influenced by family background effects, as both parental education and SES exhibited positive and strong influences on institutional selectivity decisions across two U.S. cohorts. For field of study choices, moderate family background effects, strong and consistent academic ability effects and growing academic aspiration effects were found across most analyses, lending support to theories that predict family background has direct and indirect effects on higher education choices.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Sulphur Isotopes in the White Pine Mine, Ontonagon County, Michigan

contributor:
Schwarcz, H.P
Crocket, J.H.
Geology

subject:
ore specimens
White Pine Mine
isotopes
carbon
sulphur
boron
sulphide

abstract: Ore specimens from the cupriferous zone of the basal Nonesuch shale at the White Pine Mine were analysed for sulphur isotopes, carbon and sulphide contents and boron. The results of the analyses were discussed in relation to a biogenic-syngenetic mineralization process for the ore body. A model, based on the δS³⁴sulphide frequency distribution, was developed to determine the δS³⁴ sulphate value of the lower Nonesuch paleoenvironment. A transmitted light microscopic examination of chlorite was undertaken in order to present a more complete picture of this proposed source for copper in the cupriferous zone of the Nonesuch shale.

abstract: Thesis

abstract: Master of Science (MSc)


title: Three Essays on Credit Risk Modeling

contributor:
Hurd, Tom
Mathematics

subject: credit, risk, bank, market, asset,

abstract:
Credit risk is the risk of losses due to the failure to fulfil the obliged payment from a debtor or a counterparty. It is one of the three major components of risks that a bank faces as defined in the new Basel Accord. The credit risk literature has experienced similar rapid growth as the credit market itself. There are currently four different approaches to analyzing credit risk: structural, reduced-form, incomplete information and hybrid models. Even though there are large volumes of published research papers and books on credit risk, our understanding and management skills in this area are still very limited as evidenced by the recent crash of the subprime market. This thesis combines three working papers on credit risk modeling and aims at adding some insights and contributions to the current credit risk literature.

In the first paper, we propose to randomize the initial condition of a generalized structural model, where the solvency ratio instead of the asset value is modeled explicitly. This initial randomization assumption is motivated by the fact that market players cannot observe the solvency ratio accurately. We find that positive short spreads can be produced due to imperfect observation on the risk factor. The two models we have considered, the Randomized Merton (RM)-II and the Randomized Black-Cox (RBC)-II, both have explicit expressions for Probability of Default (PD), Loss Given Default (LGD) and Credit Spreads (CS). In the RM-II model, both PD and LGD are found to be of order of √T, as the maturity T approaches zero. It therefore provides an example that has no well-defined default intensity but still admits positive short spreads. In the RBC-II model, the positive short spread is generated through the positive default intensity of the model. Because explicit formulas are available, these two Randomized Structure (RS) models are easily implemented and calibrated to the market data. This is illustrated by a calibration exercise on Ford Motor Corp. Credit Default Swap (CDS) spread data.

In the second paper, we introduce the inverse-CIR (iCIR) intensity model of credit risk. A multi-firm intensity-based model is constructed where negative correlations are built through the negative correlation between the Cox-Ingersoll-Ross (CIR) process and its inverse. This parsimonious setting allows us to form rich correlation structures among short spreads of different firms, while keeping nonnegative conditions for interest rates and short spreads. The bond prices are given by explicit expressions involving confluent hypogeometric functions. This model can be regarded as an extension of the Ahn & Gao (1999) one factor iCIR model on interest rates to a multi-factor framework on credit risk.

 In the third paper, we derive several forms of the equity volatility as a function of the equity value, from the structural credit risk literature. We then propose a new jump to default model by taking the equity volatility to be of the form implied by the models of Leland (1994) and Leland & Toft (1996). This model involves a process we call the Dual-Jacobi process and which has explicit formulae for its moments. Gram-Charlier expansions are then applied to approximate bond and call prices. Our model generalizes Linetsky (2006) by incorporating a local volatility which is bounded below by a positive constant. This local volatility will decrease to a positive constant for increasing stock prices, making the stock process asymptotic to Geometric Brownian Motion (GBM). In this sence, our model is more realistic than Constant Elasticity of Variance (CEV) models.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Modeling Vaccination Strategies for the Control and Eradication of Childhood Infectious Disease

subject: modeling, vaccination strategies, eradication, childhood, infectious, disease

abstract:
The main body of this thesis deals with three related concepts pertaining
to vaccination strategies for childhood infectious disease. Chapter 2 deals
with the implications of reversion in the Oral Polio Vaccine on global polio
eradication programs. Chapter 3 explores the phenomenon of contact or
secondary vaccination in the use of live-attenuated virus vaccines. Chapter
4 explores the importance of demographic stochasticity in pulse vaccination
campaigns. largely focusing on measles dynamics. Abstracts for each chapter
are given below.

Poliomyelitis vaccination via live Oral Polio Vaccine (OPV) suffers from the inherent problem of reversion: the vaccine may, upon replication in the human gut, mutate back to virulence and transmissibility resulting in circulating vaccine derived polio viruses (cVDPVs). We formulate a general mathematical model to assess the impact of cVDPVs on prospects for polio eradication. We find that for OPV coverage levels below a certain threshold, cVDPVs have a small impact in comparison to the expected endemic level of the disease in the absence of reversion. Above this threshold, the model predicts a small but significant endemic level of the disease, even where standard models predict eradication. In light of this, we consider and analyze three alternative eradication strategies involving a transition from continuous OPV vaccination to either continuous Inactivated Polio Vaccine (IPV), pulsed OPV vaccination, or a one-time IPV pulse vaccination. Stochastic modeling shows continuous IPV vaccination is effective at achieving eradication for moderate coverage levels, while pulsed OPV is effective if higher coverage levels are maintained. The one-time pulse IPV method may also be a viable strategy, especially in terms of the number of vaccinations required and time to eradication, provided that a sufficiently large pulse is practically feasible. More investigation is needed rq?;arding the frequency of revertant  virus infection resulting directly from vaccination, the ability of IPV to induce gut immunity, and the potential role of spatial transmission dynamics in eradication efforts.

Viruses contained in live-attenuated vims vaccines (LAVV) can be transmitted between individuals, resulting in secondary or contact vaccinations. This fact has been exploited successfully in the use of the Oral Polio Vaccine (OPV) to better control wild polio viruses. In this work we analyze general LAVV vaccination models for infections that confer lifelong immunity. We consider both standard (continuous) vaccination strategies and pulse vaccination
programs (where mass vaccination is carried out at regular intervals).
For continuous vaccination, we provide a complete global analysis of a very
general compartmental ordinary differential equation LAVV model. We find
that the threshold vaccination level required for eradication of wild virus
depends on the basic reproduction numbers of both the wild and vaccine
viruses, but is otherwise independent of the distributions of the durations in
each of the sequence of stages of disease progression (e.g., latent, infectious,
etc.). Furthermore, even for vaccine viruses with reproduction numbers below
one. which would naturally fade from the population upon cessation of
vaccination, there can be a significant reduction in the threshold vaccination
level. The dependence of the threshold vaccination level on the virus reproduction numbers largely generalizes to the pulse vaccination model. For
shorter pulsing periods there is negligible difference in threshold vaccination
level as compared to continuous vaccination campaigns. Thus, we conclude
that current policy in many countries to employ annual pulsed OPV vaccination
does not significantly diminish the benefits of contact vaccination.

 In the last two decades, many countries have implemented pulse vaccination
for infectious diseases (mass vaccination campaigns repeated annually or at
other regular intervals). Based on deterministic mathematical models, previous work has shown that the total expected cost of control or eradication
(measured by the number of vaccine doses required) is identical for pulse
vaccination (with any pulse interval) and for traditional, continuous vaccination. We reconsider this problem using stochastic epidemic models (both by direct simulation and by employing a moment closure approximation). We focus on measles and show that demographic stochasticity has a large impact on the relative success of pulse and continuous vaccination programs, even for well-mixed populations as large as 10 million.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: ADVANCED ELECTRODE MATERIALS FOR ELECTROCHEMICAL SUPERCAPACITORS

contributor:
Zhitomirsky, Igor
Materials Science and Engineering

subject:
colloid
dispersion
electrophoretic deposition
manganese dioxide
polypyrrole
vanadium nitride
carbon nanotubes
graphene
asymmetric
supercapacitor

abstract:
Advanced dispersants were discovered for the fabrication of homogeneous suspensions of multi-walled carbon nanotubes (MWCNT), graphene, and manganese dioxide (MnO2) in both ethanol and water. Thin films of MWCNT, graphene, MnO2, composite films of MWCNT-MnO2 and MWCNT-graphene were prepared using electrophoretic deposition (EPD) and electrolytic deposition (ELD) methods. The mechanisms of dispersion and deposition were investigated. Cathodic EPD was achieved for MWCNT and graphene using positively charged dispersants. Co-deposition of MWCNT and MnO¬2 was performed using a co-dispersant, which dispersed both MWCNT and MnO2 in ethanol. Composite films were tested for electrochemical supercapacitor (ES) purposes.
Pulse ELD was used to deposit porous MnO2 coatings on Ni foam substrates from KMnO4 solutions. Cathodic deposition offered advantages, compared to anodic deposition, because the problems, related to anodic dissolution of metallic substrates, can be avoided. The pulse ON/OFF times had significant influence on the morphology and structure of MnO2 films, which further determined the capacitive performance. The influence of MnO2 film thickness on specific capacitance was investigated.
Porous and conductive vanadium nitride (VN) was synthesized using melamine as a reducing agent. To further improve film conductivity and specific surface area, MWCNT were incorporated into VN matrix during synthesis. VN-MWCNT composite electrodes and VN-MWCNT/MnO2-MWCNT asymmetric supercapacitor cells were fabricated and tested. The electrodes and cells exhibited excellent electrochemical capacitive performance with good cyclic stability. The asymmetric supercapacitor device showed a voltage window up to 1.8 V, which was the combination of voltage window of VN-MWCNT (-0.9 V--0 V) and MnO2-MWCNT (0 V--0.9 V).
Polypyrrole (PPy) coated MWCNT were synthesized in ethanol with ammonium peroxydisulfate solution as an oxidant. The effects of dopants to PPy morphology and conductivity was investigated. Dopants with electrochemical active groups were selected for the synthesis of PPy nanoparticles, where dopants also contributed to the capacitance of the polymer based materials. Both PPy-MWCNT/PPY-MWCNT symmetric supercapacitors and VN-MWCNT/PPY-MWCNT asymmetric supercapacitors were fabricated and tested, where the voltage windows were 0.9 V for the former and 1.3 V for the later. The increase of voltage window was ascribed to the asymmetric structure and negative voltage window of VN-MWCNT composite.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Volta River Flows Stochastic Modelling and Forecasting

subject: Volta, River, Authority, lake, stochastic model, forecasting

abstract:
 The Volta River Authority (VRA) is responsible for the generation
and transmission of power in Ghana. For this purpose, VRA owns
and operates two hydroelectric generating stations (at Akosombo
and Kpong) with a combined installed capacity of 1060 Kw. The
Akosombo plant is served by the Lake Volta Reservoir. Prediction
of inflows into the Volta Lake is one of the important functions
of the reservoir management group.

For this project, some of the more recent methods of mathematical modelling are investigated with a view to building a simple stochastic model which adequately represents and forecasts the Volta river average monthly flow. The Box-Jenkins family of
models are employed in this exercise. A parsimonious model in the
form of a seasonal autoregressive integrated moving average
(SARIMA) model is arrived at which adequately models and
forecasts the available data.

The selected model is reasonably easy to set up, has few parameters to estimate and therefore making the updating of these parameters a relatively simple task.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: DISCOVERY AND APPLICATIONS OF NOVEL PROTEIN BASED MOLECULAR MARKERS FOR BACTERIAL CLASSIFICATION AND IDENTIFICATION

contributor:
Gupta, Radhey S
Biochemistry and Biomedical Sciences

subject:
Biochmistry
Genomics
Taxonomy
Bioinformatics
Molecular Biology
Sequencing
Evolution
Phylogeny

abstract: The class Gammaproteobacteria and its different main orders are currently classified solely on the basis of their branching in phylogenetic trees. In most cases, no molecular, biochemical or physiological characteristics are known for their demarcation. The availability of genomic sequence data has enabled the discovery of two types of molecular characteristics in the forms of Conserved Signature Indels (CSIs) and Conserved Signature Proteins (CSPs) that provide novel means for identification and demarcation of prokaryotes. In the following work, numerous CSIs and CSPs have been identified for different orders within the class Gammaproteobacteria, with particular focus on Pasteurellales, Xanthomonadales and “Enterobacteriales”. The order Pasteurellales contains a single family, Pasteurellaceae, harbouring many important human and animal pathogens. We have discovered a large number of novel CSIs that are specific for either all Pasteurellales or several distinct clades within this order of bacteria. Based upon these CSIs, we have been able to demarcate the “sensu stricto” members of the genera Actinobacillus, Haemophilus, and Pasteurella that are presently polyphyletic. Similarly, we have identified numerous CSIs for the phytopathogens-containing order Xanthomonadales and have used them in conjunction with phylogenetic analyses for the taxonomic reorganization of the members of this order. The Xanthomonadales species that branched monophyletically and shared CSIs were grouped into one of two families within the order Xanthomonadales while the other species were transferred to a new order. This work also reports many CSIs and CSPs for the phytopathogenic genera Dickeya, Pectobacterium and Brenneria from the order “Enterobacteriales” and this work also discusses the usefulness of CSIs and CSPs for understanding prokaryotic systematics and taxonomy. Additionally, based upon the species distribution of CSIs, we have also examined the impact of LGT on prokaryotic phylogeny/systematics. The extensive work on CSIs that we have reviewed supports the notion that the genetic changes responsible for them have been inherited predominantly in a vertical manner following Darwinian mode of evolution. The molecular markers discovered in this work, because of their taxa specificities, provide valuable means for genetic and biochemical studies that should lead to discovery of novel biochemical and physiological characteristics of the studied groups of bacteria and they also provide new tools for their diagnostics and as potential drug targets for these bacteria.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Sedimentation Processes in Anchialine Caves of the Yucatan Peninsula - The Role of Karst Topography and Vegetation

contributor:
Reinhardt, Eduard
School of Geography and Geology

subject: Karst, Anchialine, Caves, Mangrove, Yucatan

abstract:
Understanding the mechanisms that control sedimentation in the anchialine caves of the Yucatan Peninsula, Mexico is vital for interpreting the sedimentary deposits therein. External forcing mechanisms of varying scales, such as eustatic sea-level rise and large storm events, can have a significant influence on the rate and composition of sediment transported and deposited in the cave. Using sediment cores, high resolution radiocarbon dating, cave mapping and continuous aquifer attribute data, it was shown that sedimentation patterns in the cave were not controlled by sea-level rise/fall alone. Overlying vegetation and cave physiography were controlling factors which resulted in sedimentation in the cave being transient in time and space.
The coastal aquifer responded to seasonal variations in precipitation but also showed a broad regional response to intense rainfall associated with Hurricane Ingrid in 2013.  Due to the extensive hydraulic conductivity of the aquifer, the hydrologic response to Hurricane Ingrid was shorted lived (weeks) while its effect on sedimentation in the cave lasted for months. Sedimentation rates in the cave did not respond to elevated precipitation alone but showed a link with overlying vegetation. In regions of the cave with overlying mangrove forest, sedimentation was significantly higher than areas with tropical forest coverage. Mangrove forests baffled sediment creating an aquitard which resulted in the ponding of meteoric waters and subsequent enrichment in nutrients. Nutrient rich meteoric waters were funneled into cenotes increasing primary productivity for organic matter sediment production.
 Sedimentary deposits in anchialine caves are subject to punctuated sedimentation as a result of external forcing mechanisms or triggers. In the case of Yax Chen the trigger for sedimentation was not contemporaneous with Holocene sea-level rise. This has important implications for the use of cave sediments as proxies for sea-level research and paleo hurricane studies.

abstract: Thesis

abstract: Candidate in Philosophy


title: Part A: Neutron Radiographic Studies at the Chalk River Nuclear Reactor / Part B: Microwave Measurements of Insulator Materials

title: Part A: Industrial Project

title: Part B: McMaster (On-Campus) Project

contributor:
Harms, A.A.
Campbell, C.K.
Engineering Physics

subject:
Chalk River NRX reactor
neutron radiography
neutron beam
zirconium-based alloys
insulator materials
microwave frequencies

abstract: The thesis contains two separate projects: Part A and Part B.

abstract:
Part A: No abstract provided. Part B: A method for measuring the complex permittivity of insulator materials at microwave frequencies is described in detail. Results of dielectric measurements using this technique are in good
agreement with data from other sources. MKS units are used in this report.

abstract: Thesis

abstract: Master of Engineering (MEngr)


title: Mixing and Aeration Performance of a Single Plate Vortex Ring Generator in a Natural Pond

contributor:
Latto, Brian
Mechanical Engineering

subject:
plate vortex ring generators
pond research
mixing
ph
BOD
COD

abstract:
 This thesis describes the study of plate vortex ring generators invented and developed by Latta and modified and constructed by E.S.Fox. The vortex ring generator has been applied to destratify and aerate a natural pond in this research. Experiments were conducted to mix and aerate a stagnant and stratified pond in a natural, outdoor setting. Mixing times, temperatures, dissolved oxygen, BOD, COD and pH were measured for each experiment trial. A fluctuating single plate vortex ring generator was constructed and used in four of the five experiments with the depth of the vortex ring plate varied to determine the effect on mixing and aeration. A final experiment used a dual plate vortex ring mixer to examine the advantages of multiple plates with regard to mixing and aeration as well.

 It was found that the single plate vortex ring generator with an operating range of 1 /2 to 4/5Hz effectively destratified and mixed the pond within a 12 hour mixing duration. The generator aerated the pond by establishing a flow pattern in the pond such that the water at the surface of the pond experienced increased contact with the atmospheric air thereby transferring oxygen to the water. The impact of atmospheric air temperature proved to be a significant factor as a heat source to the pond which affected the time taken to destratify the pond. The increased oxygen transferred to the pond increased dissolved oxygen in the pond. The microbial organisms present in the pond experienced increased activity due to the increased dissolved oxygen available in the water because of the mixing action provided by the vortex ring generator.

 The summary of calculated results for all five experiments with the vortex
ring mixer is as follows: (Refer to page iv for chart).
 On the basis of the experimental results it was determined that the vortex
ring generator has a bright future as a tool to improve water quality in natural water courses.

abstract: Thesis

abstract: Master of Engineering (ME)


title: SYNTHESIS OF FUNCTIONALIZED [2.2]PARACYCLOPHANE PRECURSORS FOR FUNCTIONAL POLY(PARA-XYLYLENE) THIN FILM DEPOSITION

contributor:
Moran-Mirabal, Jose M.
Chemistry

subject: [2.2]Paracyclophane, Poly(para-xylylene), CVD polymerization, Amine-functionalization, Stability of primary amines

abstract:
Functionalized reactive polymer coatings can be used in various biomaterials applications such as immunoassays and biomolecule immobilization. Poly(para-xylelene) is a relatively new biomaterial that has attracted attention over the past few decades in these areas due to its unique properties and biocompatibility. The introduction of functionalized, particularly aminated, poly(para-xylylene) will extend the application of these polymer coatings to a wide variety of biological studies. However, their application is not widespread due to the difficulty in synthesizing the corresponding precursors. Here, a two-step method for amine functionalization of [2.2]paracyclophane via direct nitration and reduction is developed. Nitration at super acidic conditions and temperatures as low as -78 °C, improved the stability of [2.2]paracyclophane toward strong acids and successfully minimized side reactions such as oxidation and polymerization. This procedure resulted in quantitative yields of 4-nitro[2.2]para-cyclophane, which was successively reduced by Raney nickel catalysis with sodium borohydride. Compared to the many other reduction systems, this method is simple, inexpensive and applicable in large scales. It does not require harsh reaction conditions and within short reaction times, delivers quantitative amounts of the reduced product. At the end, 4-amino[2.2]paracyclophane was collected in 77% overall yield. Additionally, carboxylation of [2.2]paracyclophane using the Freidel-Crafts acylation was attempted and so far, we have been able to show the synthesis of intermediate acylated products. The successful syntheses of products were verified by FT-IR, NMR and MS, and comparison of their solubility and physical properties showed significant changes upon substitution of the pristine [2.2]paracyclophane. Then, through the chemical vapour deposition polymerization of 4-amino[2.2]paracyclophane amine-functionalized thin films were coated on Si wafer substrates and their properties were compared with Parylene N and C, two well-known poly(para-xylylene) films. The substrates coated with amino-poly(para-xylylene) showed a higher surface energy compared with those of coated with un-substituted or chlorine substituted poly(para-xylylene) films. Furthermore, results of the surface characterization conducted by grazing angle reflectance IR spectroscopy and XPS, demonstrated that the CVD process was able to transfer the functionalities of the precursors to deposited polymer films without alteration. However, with the applied process parameters we obtained a higher functional density of amine groups on the surface.
These polymer films can be deposited on a variety of substrates and be used as functional surfaces for a variety of applications. However, the stability of primary amine groups in air and aqueous solutions is a matter of concern. Aging of 4-amino-[2.2]paracyclophane and corresponding poly(para-xylylene) films in air and mili-Q water was studied via XPS and NMR spectroscopies. The results showed a decrease in the amount of primary amines with storage time in air or water for both aminated precursor and polymer. The kinetics for these changes, however, were not equal for the precursors and polymer films. The decay of amine groups was accompanied by the appearance and increase of oxygen, indicating that the decrease of available amine groups is associated with oxidation which can transform them to more stable amide and nitro compounds. In total, practical challenges involved in manufacture, durability and applications of amine-functionalized Parylene coatings are discussed and a reliable scheme for fabricating such films with high tunabiliy of the surface functional density is demonstrated. The highly practical method presented here provides great potential for widespread application of amine-functionalized poly(para-xylylene) as an outstanding biomaterial for microarrays, tissue engineering and cell culture studies.

abstract: Thesis

abstract: Master of Science (MSc)


title: SYNTHESIS OF FUNCTIONALIZED [2.2] PARACYCLOPHANE PRECURSORS FOR FUNCTIONAL POLY(PARA-XYLYLENE) THIN FILM DEPOSITION

abstract: Functionalized poly(para-xylylene) (PPX) coatings can be useful for biomaterials applications due to their biocompatibility and useful chemistry for the immobilization of biomolecules. However, their application is not widespread due to the difficulty in synthesizing the corresponding precursors. Here, a two-step method for amine functionalization of [2.2]paracyclophane (PCP) via direct nitration and reduction is developed. Nitration at super acidic conditions and temperatures as low as -78 °C, improved the stability of PCP toward strong acids and successfully minimized side reactions such as oxidation and polymerization. This procedure resulted in quantitative yields of 4-nitro-PCP, which was successively reduced by Raney nickel catalysis with sodium borohydride. Compared to the many other reduction systems, this method is simple, inexpensive and applicable in large scales. Additionally, carboxylation of PCP using the Freidel-Crafts acylation was attempted and so far, we have been able to show the synthesis of intermediate acylated products. Then, through the chemical vapour deposition polymerization of amino-PCP amine-functionalized poly(para-xylylene) (PPX-A) thin films were coated on Si wafer substrates. The substrates coated with PPX-A showed a higher surface energy compared with those of coated with un-substituted or chlorine substituted PPX films. Furthermore, results of the surface characterization demonstrated that the CVD process was able to transfer the functionalities of the precursors to deposited polymer films without alteration. However, the stability of primary amine groups in air and aqueous solutions is a matter of concern. Aging of amino-PCP and corresponding PPX-A films showed a decrease in the amount of primary amines which was accompanied by the appearance and increase of oxygen, indicating that the decrease of available amine groups is associated with oxidation. Nevertheless, both aminated precursor and polymer films remained intact under argon. The method presented here has great potential for widespread application of PPX-A as a convenient biomaterial for microarrays and cell culture.

abstract: Thesis

abstract: Master of Science (MSc)


title: Enhanced Anaerobic Digestion of Municipal Wastewater Sludge using Microbial Electrolysis Cells

contributor:
Younggy, Kim
Civil Engineering

subject:
Anaerobic digestion
Microbial electrolysis cells
Wastewater sludge
Anaerobic digestion model no.1

abstract: In municipal wastewater treatment, anaerobic digestion is the slowest process requiring at least 15 day solids retention time (SRT). Treating only a small fraction of the total wastewater stream, anaerobic digesters require large reactor volumes and consistent heating (40°C). Thus, there is a growing need to investigate techniques to improve digestion efficiency. The long SRT requirement is a result of the time required for biological reactions such as hydrolysis and acetoclastic methanogenesis. There are numerous pretreatment methods which have so far been developed to particularly enhance hydrolysis. These pretreatment methods include thermalization, mechanical treatments, and chemical treatments. These methods aim to increase the degradability of the influent waste sludge which in turn will increase the efficiency of the digestion process. The goal of the research presented in this thesis is to enhance another limiting biological reaction: acetoclastic methanogenesis. Microbial electrolysis cell (MEC) technology was integrated into lab-scale anaerobic digesters in order to accelerate biosolids destruction under various SRT and temperature conditions. Various mathematical simulations were conducted using a developed steady-state ADM1 (Anaerobic Digestion Model No.1) model to further evaluate the performance of the digesters. The results of the research indicate that the proposed method is effective at shortened SRTs (e.g., 6 days) and can enhance the stability of anaerobic digestion when exposed to variations in temperature and influent composition.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: TRANSFUSION-RELATED ALLOIMMUNIZATION IN CHILDREN: EPIDEMIOLOGY AND EFFECTS OF CHEMOTHERAPY (TRACE-EC)

title: EFFECTS OF CHEMOTHERAPY ON RED BLOOD CELL ALLOIMMUNIZATION IN CHILDREN

contributor:
HEDDLE, NANCY
Health Research Methodology

subject:
Red Cell
Alloimmunization
Pediatrics
Oncology
Chemotherapy

abstract:
Background: Red cell transfusions can lead to alloimmunization; however, pediatric alloimmunization frequency has not been well studied, and it may vary among diagnostic subgroups. Subgroups such as pediatric hematology/oncology patients require numerous transfusions during chemotherapy, but the immunosuppressive effect of chemotherapy on alloimmunization is unknown. One study demonstrated reduction in IgM and IgG in pediatric leukemia patients (Martín Ibáñez 2003); hence, one could hypothesize that chemotherapy suppresses alloimmunization.

Objectives: This study aimed to: 1) describe alloimmunization frequency and antibody specificities in transfused pediatric patients; and 2) determine if chemotherapy affects the frequency of alloimmunization.

Methods: A retrospective cohort study of pediatric patients (transfused between April 2002 and November 2011 at Hamilton Health Sciences) was performed. Data were extracted from 3 sources: a blood utilization database; the Laboratory Information System; and chart reviews. The chemotherapy treatment group included pediatric hematology/oncology patients stratified by HSCT status and diagnosis; control cohort included other pediatric patients not diagnosed with cancer. Control patients with hemoglobinopathies were analyzed separately due to increased alloimmunization. Alloimmunization was defined as clinically significant IgG alloantibody formation.

Results: There were 1273 patients in the study: 949 in control group; 324 in study group. Alloimmunization was 1.6% overall: 0.6% (95% CI: 0, 1.47) in study group; 1.3% (95% CI: 0.58, 2.06) in control group. The association between chemotherapy and alloimmunization was not significant (p value = 0.38 Fisher’s exact test; OR 0.46, 95% CI: 0.10, 2.09). Due to low outcome rate, logistic regression to explore the association was not feasible.

Conclusions: This is the first study exploring the frequency of alloimmunization in pediatric patients by diagnosis and the association between chemotherapy and alloimmunization. The frequency of alloimmunization was low and no association between chemotherapy and alloimmunization was observed. Low event rate would have contributed to low power.

abstract: Thesis

abstract: Master of Science (MSc)


title: Mei-A Module System for Mechanized Mathematics Systems

contributor:
Farmer, William M.
Computer Science

subject: module systems, Mei, mechanized, mathematics systems, functors,

abstract: This thesis presents several module systems, in particular Mei and DMei, designed for mechanized mathematics systems. Mei is a λ-calculus style module system that supports higher-order functors in a natural way. The semantics of functor application is based on substitution. A novel coercion mechanism integrates a parameter passing mechanism based on theory interpretations with simple λ-calculus style higher-order functors. DMei extends Mei by supporting dependent functor types. Mei is the first module system that successfully supports both higher-order functors and a parameter passing mechanism based on theory interpretations.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Covert Cerebral Ischemia After Noncardiac Surgery

contributor:
Devereaux, Philip J
Health Research Methodology

subject:
Stroke
Noncardiac surgery
Covert stroke

abstract:
Background
200 million patients undergo noncardiac surgery every year. Overt stroke after noncardiac surgery is not common, but has a substantial impact on duration and quality of life.  Covert stroke in the nonsurgical setting is much more common than overt stroke, and associated with an increased risk of cognitive decline and dementia.  Little is known about covert stroke after noncardiac, noncarotid artery surgery.
Methods
	We undertook a prospective cohort pilot study to inform the incidence of covert stroke after noncardiac, noncarotid artery surgery, and to determine the feasibility of a full prospective cohort study to characterize the epidemiology of perioperative covert stroke. Patients underwent a brain MRI study between postoperative days 3-10, and were followed up at 30 days after surgery.
Results of the pilot study
	We enrolled a total of 100 patients from 6 centres in 4 countries, demonstrating excellent recruitment and no loss to follow-up at 30 days after surgery.  The incidence of perioperative covert stroke was 10.0% (10/100 patients, 95% confidence interval 5.5% to 17.4%).
Full study protocol
	We describe a proposal for a prospective cohort study of 1,500 patients. An MRI study of the brain will be performed between postoperative days 2 and 9. The primary outcome is cognitive function, measured 1 year after surgery using the Montreal Cognitive Assessment tool. We will perform multivariable logistic regression analysis where the dependent variable is the change in cognitive function 1 year after surgery, and the independent variables are incidence of perioperative covert stroke and other risk factors for cognitive decline.
Conclusions
	This international multicentre pilot study suggests that 1 in 10 patients ≥65 years of age experiences a perioperative covert stroke.  The proposed protocol describes a larger study which will determine the impact of perioperative covert stroke on patient-important outcomes.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: This thesis describes a program of research to investigate silent stroke after surgery.


title: Homogenous and Carbon Graded High Manganese Steels

contributor:
McDermid, Joseph
Materials Science and Engineering

subject: High Manganese Steels

abstract:
High manganese steels offer an outstanding combination of high strength and ductility owing to their high sustained strain hardening rates. The strain-induced deformation products in these steels (mechanical twins and ε-martensite) increase the work hardening rates by acting as barriers for dislocation motion. A significant determinant of the deformation products in these steels is the value of stacking fault energy (SFE), which is in turn strongly dependent on the alloy manganese and carbon contents. The main objective of present work is to investigate the microstructural evolution and mechanical behaviour of both homogenous and compositionally graded high-Mn steels, where C compositional gradients were introduced into the latter.
The starting materials in this work were cold rolled Fe-22Mn-0.6C and Fe-30Mn-0.6C steels. For both starting alloys, decarburization and annealing heat-treatments were used to obtain four homogenous alloys with carbon contents of approximately 0, 0.2, 0.4 and 0.6 wt. % with similar grain sizes. Decarburization heat treatments were also applied to obtain three carbon graded Fe-22Mn-C alloys (G1, G2, G3) and one carbon graded Fe-30Mn-C alloy. Microstructural observations determined the deformation products to be mechanical ε-martensite for the 22Mn-0C and 22Mn-0.2C alloys and mechanical twins for the 22Mn-0.6C, 30Mn-0.2C, 30Mn-0.4C and 30Mn-0.6C alloys. For the 22Mn-0.4C and 30Mn-0C alloys, both mechanical twins and ε-martensite were observed during deformation. For all the carbon graded Fe-22Mn-C alloys, the dominant deformation products changed from mechanical ε-martensite at the near-surface layer to a mixture of mechanical twins and ε-martensite or mechanical twins only at the inner cross-section layers. In the case of carbon graded Fe-30Mn-C alloy, the deformation products altered from a combination of mechanical ε-martensite and twins at the near-surface layer to mechanical twins at the inner cross-section layers.
For all the homogenous alloys, the ultimate tensile strength and uniform elongation increased with increasing alloy carbon content. The work hardening behaviour of these steels was successfully modelled using a modified Kocks-Mecking model, in which the work hardening was the sum of the dislocation glide contribution and the phase transition contribution – mechanical twinning and/or mechanical ε-martensite formation – as dictated by the formation kinetics of both deformation products. For both alloy systems, the mechanical properties of the carbon graded alloys were not as good as the monolithic 22Mn-0.6C and 30Mn-0.6C alloys due to their lower sustained high work hardening rates.
Both the mechanical ε-martensite and twin formation were found to follow a sigmoidal kinetic with strain. In the case of twin formation homogenous alloys, the saturated volume fraction of twins was directly proportional to the alloy SFE. For the ε-martensite formation homogenous alloys, the ε-martensite volume fraction at fracture was found to be strongly dependent on alloy SFE, where it declined sigmoidally with increasing alloy SFE. It was also found that the ε-martensite volume fraction at fracture – approximately 0.7 – was independent of SFE for SFE  6 mJ/m2. This indicated that the critical damage mechanism was determined by the kinetics of the ε-martensite formation, which was in turn dictated by the alloy SFE. Finally, it was found that the stress for the onset of mechanical twinning – and consequent increase in the work hardening rate – for the higher SFE, twinning dominated alloys was linearly proportional to the alloy SFE.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)