VictorJuiz/thesis huggingface dataset:
Effects of a Eucaloric Low Glycemic Index Diet on Insulin Sensitivity and Intramyocellular Lipid Content in Adults with Abdominal Obesity

Individuals with abdominal obesity are at higher risk for developing type 2 diabetes, predisposing cardiovascular events and insulin resistance. Low glycemic index (GI) diets may be beneficial in the management of insulin resistance. Insulin resistance is associated with increased intramyocellular lipid (IMCL) content as measured by proton nuclear magnetic resonance spectroscopy (1H-MRS). The primary objective of this thesis was to determine whether a low GI diet can improve insulin sensitivity by reducing IMCL of skeletal muscle. One hundred and twenty-one male and female participants aged 30 to 70 years (mean+SD, 53+10)) with abdominal obesity, entered a 4 to 6 week weight-maintaining, low-fat dietary advice run-in phase. Of the 121 eligible participants, 95 completed the run-in phase and were randomly assigned to either a low-GI (LGID, n=48) or high-GI diet (HGID, n=47) for 24 weeks. Participants underwent a 75g oral glucose tolerance test (OGTT) and had soleus-muscle IMCL measured by 1H-MRS at the beginning and end of the intervention period. Insulin sensitivity was assessed by the homeostatic model assessment index (HOMA) and the insulinogenic index (ISI) was calculated for insulin secretion. At the end of the run-in phase, there were significant reductions in serum total-, LDL-, and HDL-cholesterol (all, p<0.0001) and an increase in fasting plasma glucose (p<0.05). In 57 participants who wore a continuous glucose monitoring system for 24 hours during the run-in period, a total of 30% (p<0.001) of the variation in the incremental area under the blood glucose curve after self-selected breakfast meals was explained by GI. After 24 weeks, diet GI was significantly lower in the LGID than HGID group (55.5+3.1 vs 63.9+3.1, p<0.0001). Plasma glucose 60 minutes after the OGTT was significantly lower on the LGID than at baseline (p<0.05) and there was a non-significant trend towards an increase in ISI (p=0.07). On the HGID, ISI increased significantly from baseline (p<0.01). It is concluded that the LGID reduced 60 minute plasma glucose but did not significantly affect IMCL or insulin sensitivity in individuals with abdominal obesity.

Keywords: glycemic index
intramyocellular lipid IMCL
obesity
insulin sensitivity
Advisor: Wolever, Thomas M. S.
Identity and Wisdom of Young Adults in Canada and Pakistan with Asperger Syndrome: A Cross-cultural Study

This cross-cultural study investigates identity and wisdom in people with Asperger syndrome (AS). The diagnostic characteristics of Asperger syndrome are universal, as they are manifest in particular outward behaviours (DSM-4). One of the aims of this study is to explore whether or not identity and wisdom are also universal in people with AS. Interviews were conducted that asked participants about their own lives, as well as about the acquaintances and historical figures to whom they look to for wisdom. Some self-report measures of identity, values, wisdom, and well-being were also administered to the participants. Forty-six male participants (half diagnosed with Asperger syndrome) were recruited from Karachi, Pakistan, and the Greater Toronto Area (GTA), Canada. People with AS were matched with non-autistics according to age. The results of this study showed that the Canadian Asperger group was significantly higher in social identity, and lower in personal integrity, as compared to the Pakistani Asperger group. The value of conservation was significantly higher in the Asperger groups than in the control groups. Mean scores on the 3-dimensional wisdom scale differed significantly between the Asperger and control groups, but remained the same between the two Asperger groups. People with AS were equally satisfied with their lives as compared to non-autistics. There was a greater emphasis on the theme of communion for the Pakistani Asperger group than for the Canadian Asperger group. Results also found a greater emphasis on the theme of personal agency in both the Asperger groups, as compared to the control groups. The Pakistani Asperger group mainly considered religious figures to be the wisest in history, whereas the Canadian Asperger group primarily nominated scientists as the wisest figures in history. Both the Asperger groups considered family members to be the wisest among their acquaintances. The concept of wisdom centered on the theme of cognition for both Asperger groups. The study was limited to male participants only, and future research should study both genders.

Keywords: Developmental psychology
Personality
Advisor: Ferrari, Michel
Regulation of Fas-deficient Lymphoproliferative Double Negative T Cells by Interferon Gamma and the Fc Receptor Gamma Chain

The Fas pathway is critical for the maintenance of normal T cell homeostasis. Humans and mice with defects in this pathway exhibit the accumulation of large numbers of peripheral lymphocytes and lupus-like autoimmunity. A major feature of these organisms is the accumulation of non-NK TCRαβ+CD4-CD8- “double negative” (DN) T cells. While regulatory T cells (Tregs) with the DN phenotype have been extensively characterized in Fas-sufficient mice and humans, limited data exist on the role of DN T cells as Tregs in Fas-deficient animals. In fact, most of the literature suggests that the DN T cells accumulating in Fas-deficiency states are pathogenic, contributing to secondary lymph node enlargement and autoimmune disease. In this body of work, data are presented that illustrate that Fas-deficient lymphoproliferative (LPR) DN T cells can act as Tregs in an interferon γ (IFNγ)- and Fas ligand (FasL)-dependent fashion toward Fas-sufficient T cells. LPR DN T cells needed to be able to secrete and respond to IFNγ in order to upregulate surface FasL, in order to ameliorate GVHD mediated by CD4+ T cells in vivo and to suppress the proliferation of and kill activated CD4+ T cells in vitro. FcRγ, a key molecule involved in innate immune responses, can substitute for CD3ζ in the T cell receptor (TCR) of mouse and human T cells in certain circumstances; in doing so, it is essential for the regulatory function of TCR transgenic DN Tregs. FcRγ-deficient LPR mice were found to have exacerbated T cell accumulation and early mortality. We show that while FcRγ expression was required for LPR DN T cells to regulate CD4+ and CD8+ T cells responding to alloantigens in vitro and in vivo, it does not control autologous lymphoproliferation in LPR mice by supporting the function of a regulatory cell, nor does it affect the rate of proliferation of LPR T cells in vivo. Instead, FcRγ-expressing LPR CD4+, CD8+ and DN T cells were found to be undergoing apoptosis at a high rate in vivo, and in contrast to their FcRγ-deficient counterparts, FcRγ+ LPR DN T cells were capable of undergoing TCR restimulation-induced cell death (RICD). The data presented in this thesis therefore show that LPR DN T cells can exhibit IFNγ-, FasL- and FcRγ-dependent regulatory function, and also illustrate a previously unknown function for FcRγ in controlling the expansion of Fas-deficient T cells. The implications of these data for autoimmune lymphoproliferative syndromes, and normal T cell homeostasis, are discussed.

Keywords: Fas
Interferon gamma
Fc receptor common gamma chain
Autoimmune lymphoproliferative syndrome
Graft-versus-host disease
Regulatory T cells
Double negative T cells
Advisor: Zhang, Li
Information Transmission using the Nonlinear Fourier Transform

The central objective of this thesis is to suggest and develop one simple, unified method for communication over optical fiber networks, valid for all values of dispersion and nonlinearity parameters, and for a single-user channel or a multiple-user network. The method is based on the nonlinear Fourier transform (NFT), a powerful tool in soliton theory and exactly solvable models for solving integrable partial differential equations governing wave propagation in certain nonlinear media. The NFT decorrelates signal degrees of freedom in such models, in much the same way that the Fourier transform does for linear systems. In this thesis, this observation is exploited for data transmission over integrable channels such as optical fibers, where pulse propagation is governed by the nonlinear Schr\"odinger (NLS) equation. In this transmission scheme, which can be viewed as a nonlinear analogue of orthogonal frequency-division multiplexing commonly used in linear channels, information is encoded in the nonlinear spectrum of the signal. Just as the (ordinary) Fourier transform converts a linear convolutional channel into a number of parallel scalar channels, the nonlinear Fourier transform converts a nonlinear dispersive channel described by a \emph{Lax convolution} into a number of parallel scalar channels. Since, in the spectral coordinates the NLS equation is multiplicative, users of a network can operate in independent nonlinear frequency bands with no deterministic inter-channel interference. Unlike most other fiber-optic transmission schemes, this technique deals with both dispersion and nonlinearity directly and unconditionally without the need for dispersion or nonlinearity compensation methods. This thesis lays the foundations of such a nonlinear frequency-division multiplexing system.

Keywords: Communication theory
Information theory
Optical fiber communication
Nonlinear dispersive waves
Stochastic partial differential equations
Orthogonal frequency-division multiplexing (OFDM)
Nonlinear Fourier transform
Integrable systems
Channel capacity
Solitons
Nonlinear Schrodinger equation
Interference channel
Fiber-optic
Advisor: Kschischang, Frank R.
The Role of Tort Liability in Improving Governmental Accountabilty in the Health Sector

Over the past decade, concerns with the accessibility and quality of health services have led several individuals to bring tort claims against provincial governments. Unlike other types of health sector legal claims, which have been the subject of much commentary, this thesis provides the first treatment of the tort cases against governmental defendants. To date, Canadian courts have not been receptive to these claims, striking nearly all of them on pre-trial motions, on the basis that government defendants did not owe the plaintiffs a duty of care. In order to situate the health sector tort claims within the judiciary’s broader approach to governmental liability, I compiled a dataset of all tort cases against Canadian governmental defendants from the past decade. My dataset indicates that judges have dismissed more health sector tort claims than those arising from nearly all other sectors of government activity, even accounting for other explanatory variables. I also develop a framework to categorize the judicial approaches to the test for establishing a duty of care. Canadian judges now generally conduct a comprehensive analysis of the closeness and directness of the parties’ relationship and the policy implications of tort liability in determining whether a defendant owes a plaintiff a duty of care. However, judges adjudicating health sector claims fail to appreciate the government’s modern role in the health sector and are almost singularly concerned with the policy implications of their decisions. I conclude with two policy recommendations. First, I argue that judges should more frequently permit these claims to proceed beyond the pre-trial dismissal stage to a full trial, in order to evaluate the policy concerns both for and against governmental liability with the benefit of a full evidentiary record. Second, I argue that judges should more frequently permit health sector tort claims to proceed beyond the duty of care stage of the negligence analysis to an assessment of whether the government met the standard of care. While this approach would allow judges to scrutinize the reasonableness of the government’s decisions, improving transparency and potentially motivating an improved decision-making process, it would not necessarily lead to widespread liability.

Keywords: governmental liability
health policy
tort law
accountability
negligence
health system organization
Advisor: Flood, Colleen M.
Resource Allocation in Autonomous Cellular Networks

With a fixed number of terminals and a fixed system spectrum, it can be shown that increasing the number of BSs in a cellular network results in a better network performance. However, a regular organized deployment of a cellular network with small cells is both prohibitively expensive and complicated. A possible solution is to allow the network to grow in an organic fashion. This calls for self-configurable approaches for resource allocation which not only improve the performance but also decrease the network planning as well as maintenance costs. Over the past few years, a particular type of small BSs known as femto-BSs has attracted tremendous attention from the industry and academia alike. Femto BSs operate on the licensed spectrum allocated to the cellular network. They are small, inexpensive and transmit at low power levels. Although the deployment of these small BSs result in significant improvements in the indoor coverage for both voice and data services, they only satisfy the immediate needs of the present cellular networks — namely the improvement of the indoor coverage. They do not provide a fundamental solution for a scalable architecture which can organically grow and adapt to the short and long term changes in the network. In this thesis, we propose a practical unified framework for the system design and resource allocation of cellular networks with various types of base stations (with different power budgets) deployed in an irregular fashion. We refer to these networks as autonomous cellular networks. To this end, we first introduce an adaptive localized approach to resource allocation in traditional cellular networks. We show that localized resource assignment at the cost of partial loss of orthogonality at the cell edges can provide significant gains in the network performance. In the second part of the thesis, we propose an adaptive self-configurable resource allocation framework for cellular networks. A network clustering technique is proposed which enables coordinated resource allocation in a network with irregular deployment of BSs. The performance of the proposed framework is evaluated with the regular as well as the irregular deployment of BSs.

Keywords: Resource allocation
Cellular network
Self-configuration
Advisor: Sousa, Elvino Silveira
Paired Associative Plasticity in Human Motor Cortex

This thesis consists of four chapters. In this thesis we explored associative plasticity of human motor cortex with the use of noninvasive transcranial magnetic stimulation (TMS). Paired Associative Stimulation (PAS) has grown in popularity because of its potential clinical applications. We used TMS techniques in combination with electromyographic (EMG) measurements to study cortical excitability and kinematic features of arm movement. This work has focused in a cohesive approach to answer certain fundamental questions about a) the rules of cortical plasticity and mechanism of PAS, b) the interaction between the state of neuronal excitability at the targeted cortical network and the effects of PAS, and c) translation of these effects into obvious measurable kinematic changes starting from network level changes and ending up with the behavioral modulation of arm movement. First we explored the role of GABAergic intracortical networks and intracortical facilitation on modulation of cortical excitability by showing for the first time that PAS can be conditioned by these inhibitory and facilitatory intracortical networks. Next, using standard indirect approaches utilizing peripheral EMG measures, we showed a graded excitability response for the PAS technique and showed that interactions of PAS with motor learning depends on the degree as well as the state of cortical excitability. Rules governing the interactions of brain stimulation techniques and motor learning are important because brain stimulation techniques can be used to modify, improve or disrupt motor adaptation and skill learning with great potential for clinical applications such as facilitation of recovery after stroke. TMS provide us with a unique opportunity to study the rules of plasticity at a systems level, which is a combination of synaptic and nonsynaptic (metaplastic) changes. These changes can occur either in the direction to limit the physiological range of neuronal functioning (homeostatic) or against the direction established state of neurons.

Keywords: Neuroplasticity
Associative plasticity
Transcranial Magnetic Stimulation
Advisor: Chen, Robert
Search for Neutral Minimally Supersymmetric Standard Model Higgs Decaying to Two Hadronic Taus with the ATLAS Detector in pp collisions at 7 TeV Center of Mass Energy

This thesis presents the first search for a neutral Minimal Supersymmetric Standard Model Higgs boson decaying to a pair of hadronic taus in proton-proton collisions with a center-of-mass energy of √s = 7 TeV. Results are presented for an integrated lumi- nosity of 1.056 fb−1 using data from the ATLAS detector at the Large Hadron Collider. After signal selection, 245 events are observed. The number of events is consistent the background estimate of 256 ± 26. An exclusion limit for the Higgs boson production is derived as a function of (cross-section)×(branching ratio). This limit is presented as a function of two parameters: mA and tanβ in the mmax scenario. A point in the (mA, h tanβ) phase space is excluded if the signal hypothesis is rejected at the 95% confidence level.

Keywords: MSSM Higgs
hadronic tau
Advisor: Orr, Robert S.
Conservation Genetics of Freshwater Turtles

Turtles have long life spans, overlapping generations and promiscuous mating systems. Thus, they are an ideal system with which to investigate the application of conservation genetics methods and assumptions to long-lived organisms. Turtles are also one of the most threatened groups of vertebrates and conservation genetics studies are essential to effective recovery of turtle species. This thesis has two main objectives: 1) to evaluate some common population genetics assumptions with respect to turtles and other long-lived organisms, and 2) to collect important information on the population genetics of threatened turtles in Ontario, which can be used to inform species recovery. In Chapters Two and Three, I describe the development of novel microsatellite markers for the snapping turtle and spiny softshell. In Chapter Four I demonstrate significant genetic structure in populations of the endangered spotted turtle in Ontario, and find that “bottleneck tests” may fail to detect recent population declines in small turtle populations. I also show that spotted turtles do not show the typical correlation between population size and genetic diversity. In Chapter Five I use microsatellite markers developed in Chapter Two and document population structure in the widespread snapping turtle for the first time. I compare these results with results from Chapter Four to test the traditionally accepted hypothesis that genetic diversity is reduced in small, isolated populations compared to large, connected populations. As in Chapter Four, my results suggest that the usual patterns of genetic structure and loss of diversity may not apply to turtles. In Chapter Six I conduct a conservation genetics study of the endangered Blanding’s turtle. Finally, in Chapter Seven I combine results from spotted, snapping and Blanding’s turtles to test whether vagility predicts population structure, genetic diversity and significant barriers to gene flow in three species sampled across a single landscape. Analyses reveal minimal congruence in barriers to gene flow and the three species show unexpected and contrasting patterns of diversity across the landscape. Discordant patterns among species highlight areas for further research and shed light on possible cryptic behaviour, and I discuss potential further directions for research in the Summary.

Keywords: microsatellite
spatial genetics
Emys blandingii
Chelydra serpentina
Clemmys guttata
Apalone spinifera
Advisor: Murphy, Robert W.
Observational Studies of Interacting Galaxies and the Development of the Wide Integral Field Infrared Spectrograph

Interacting galaxies are thought to be the essential building blocks of elliptical galaxies under the hierarchical galaxy formation scenario. The goal of my dissertation is to broaden our understanding of galaxy merger evolution through both observational studies and instrument developments. Observationally, I approach the goal photometrically and spectroscopically. The photometric studies better constrain the number density evolution of wet and dry mergers through five CFHTLS broad band photometry up to z~1. Meanwhile, by comparing the merger and elliptical galaxy mass density function, I discovered that the most massive mergers are not all formed via merging processes, unless the merging timescale is much longer than the expected value. Spectroscopically, the kinematic properties of close pair galaxies were studied to understand how star formation were quenched at z~0.5. I discovered that the number of red-red pairs are rare, which does not support the gravitational quenching mechanism suggested by the hot halo model. In instrumentation, one efficient way to study galaxy mergers is to use the integral field spectroscopic technique, capitalizing its intrinsic capability of obtaining 2-D spectra effectively. However, the currently available integral field spectrographs are inadequate to provide the required combination of integral field size and spectral resolution for merger studies. I, therefore, have developed two optical designs of a wide integral field infrared spectrograph (WIFIS), which I call WIFIS1 and WIFIS2, to satisfy the requirements of merger studies. Both the designs provide an integral field of 12" x 5" on 10-m telescopes (or equivalently 52" x 20" on 2.3-m telescopes). WIFIS1 delivers spectral resolving powers of 5,500 covering each of JHK bands in a single exposure; WIFIS2 does a lower power of 3,000 focusing on a shorter wavebands of zJ and H bands. All the WIFIS2 optical components have either been or being fabricated, and some of the components have been characterized in the laboratory, including its integral field unit, gratings, and mirrors. The expected completion of WIFIS based on WIFIS2 is 2013 summer, which will be followed by WIFIS1-based spectrograph in a few years.

Keywords: Galaxy Evolution
Optical Design
Advisor: Abraham, Roberto
Moon, Dae-Sik