VictorJuiz/thesis huggingface dataset:
Outcome and Predictors of In-hospital 6-week Mortality associated with Invasive Methicillin Resistant Staphylococcus aureus (MRSA) versus Methicillin Sensitive Staphylococcus aureus (MSSA) Infection

Background: Staphylococcus aureus (SA) infections are common and important within the hospital environment. The case fatality rate of invasive Staphylococcus aureus (SA) infections is between 20-40%. Whether the infection is due to methicillin resistant SA (MRSA) or methicillin sensitive SA (MSSA) may determine outcomes. Literature to date is inconclusive regarding whether antimicrobial resistance in SA affects patient outcomes. Host factors, infection-host interactions, and treatment-related factors may also influence case fatality. Objectives: The purpose of this study was to determine if patients with MRSA invasive infections were more likely to die than those with MSSA invasive infections, and what factors were associated with death. Methods: A retrospective matched case control study was designed, comparing cases of MRSA with controls of MSSA invasive disease from hospitals participating in the Canadian Nosocomial Infection Surveillance Program (CNISP). Two analyses were run: the first, to identify the variables associated with MRSA vs. MSSA infections, and the second, to determine the variables associated with death in invasive Staphylococcal aureus (S. aureus) infections. Backward logistic regression analysis was used for the MRSA vs. MSSA analysis and a hierarchical logistic regression model for assessment of risk factors for death. Results: In the logistic regression MRSA model the variables: recent prior use of antibiotics, Charlson Comorbidity Index score > 2 and not having received appropriate empiric antibiotics were associated with MRSA vs. MSSA infections. The hierarchical model identified older age, higher CCI scores, immunosuppression, bloodstream infection, septic shock, neurological dysfunction and not receiving appropriate empiric antibiotic as associated with death. MRSA infection was not more likely to be associated with increased mortality than MSSA infection. Those with a resistant infection (MRSA) however, were less likely to receive appropriate empiric antibiotic treatment. Conclusions: Appropriate empiric antibiotics are the most important and only modifiable risk factor identified. Elderly patients who are on immunosuppressive drugs and have chronic comorbid conditions need to be monitored and screened more often since they are more at risk for death than others.

Keywords: MRSA
outcomes
mortality
staphylococcus aureus
Advisor: Streiner, David
Low-power Charge-pump Based Switched-capacitor Circuits

In this thesis, low-power charge-pump (CP) based switched-capacitor (SC) circuits are proposed. The approach is validated in SC integrators and gain stages, and is shown to achieve power savings compared to conventional SC circuits. For the same thermal noise and settling performance, a CP based integrator with N sampling capacitors ideally consumes N^2 times lower OTA power compared to a conventional integrator. Practical effects such as the OTA partial slew-rate limitation and the CP parasitics reduce the power savings. In the case of a SC gain stage, reduction in power savings also occurs due to the load capacitance from the next stage. A prototype delta-sigma modulator employing a CP integrator at the front-end is fabricated. Experimental results demonstrate that the CP based ADC achieves the same performance as a conventional ADC while consuming three times lower OTA power in the front-end integrator. The CP ADC achieves 87.8 dB SNDR 89.2 dB SNR and 90 dB DR over a 10 kHz bandwidth while consuming 148 uW from a 1.2 V power supply. The conventional ADC has similar performance but dissipates 241 uW. The CP ADC figure-of-merit (FOM) is 0.369 pJ/conv-step, which is almost 40% lower than that of the conventional ADC.

Keywords: Switched-Capacitor Circuits
Charge-Pump
Delta-Sigma Modulator
Advisor: Johns, David A.
Femtosecond Laser Fabrication of Optimized Multilayered Volume Diffractive Optical Elements

Diffractive optical elements (DOEs) serve an important function in many dynamic and static optical systems. The theory and design of surface diffractive structures are well understood and practically applied at high spatial and phase resolution for a wide range of optical applications in science and industry. However, these structures normally only harness phase modulation of uniform fields for the beam diffraction and therefore limit their range of application, as well as being susceptible to surface damage. Multilayered volume diffractive elements offer a powerful opportunity to harness both phase and amplitude modulation for benefits in diffraction efficiency and beam shaping. However, multilayered combinations have been difficult to fabricate and provide only weak diffraction for phase gratings with low refractive index contrast. The advent of femtosecond laser writing inside transparent media has enabled the facile embedding of optical devices such as waveguides and diffractive optics into novel three-dimensional geometries that offer advanced functionality with compact design. In this work, femtosecond laser writing is pushed to the limits of forming high resolution phase elements with sufficiently strong refractive index contrast on which to develop volume phase gratings with the highest diffractive efficiency. The formation of both positive and negative zones of refractive index contrast together with rapid Talbot self imaging inside weakly contrasting phase gratings are major challenges here diminish the efficiency of assembled gratings. A method of strategic layering of otherwise weakly diffracting gratings onto Talbot planes is introduced to demonstrate, in FDTD models, the definitive enhancement of overall diffraction efficiency. A systematic optimization of laser writing in fused silica verify this enhancement or diminishment with weak volume gratings assembled on aligned or misaligned on Talbot planes. Advanced laser beam control methods were further demonstrated that underpin new direction for the facile assembly of highly functional DOEs that can exploit coherent light diffraction for opportunities in improving the performance of holographic devices and extend further to the powerful combination of phase and amplitude modulation control that is potentially available in a single optical device, thereby opening new directions for the design and fabrication of robust and strongly diffracting volume optical devices.

Keywords: Ultrafast lasers
Diffractive Optics
Talbot self-imaging
Volume gratings
Advisor: Herman, Peter R.
Creating Criminality: The Intensification of Institutional Risk Aversion Strategies and the Decline of the Bail Process

The question of whether or not to release an accused on bail pending case resolution involves an evaluation of the risk the accused poses to the community. In addition to this evaluation, the risk posed to the reputation of the criminal justice system should the accused re-offend while on bail has come to influence the timeliness of the bail decision as well as the conditions of the release order. It appears that questions of institutional risk have intensified strategies of process, whereby the bail decision making process has come to take considerably longer as court actors postpone making the release decision. This organizational culture of risk aversion is evidenced in the growing remand population, the dominance of adjournment requests, the presumption of surety supervision, as well as the imposition of numerous restrictive conditions of release that are questionably related to the grounds for detention and allegations of the offence. Due to the additional protections contained in the Youth Criminal Justice Act (YCJA), the expectation is bail should be more liberally used for youths. However, despite the additional legislated protections, bail practices for both adults and youths are operating in remarkably similar ways. Indeed, it appears that routine bail practices for both adults and youths are inconsistent with the essential principles of the bail process. In Canada there is a presumption in favour of release on bail and a presumption of release on the least restrictive form of release appropriate in the circumstances. Despite these principles there has been a relatively steady increase in the size of the remand population in Canada. Focusing on the situation in Ontario, this dissertation examines the bail process in an effort to understand how the remand population has come to exceed the population of sentenced prisoners in provincial prisons for both adults and youths.

Keywords: institutional risk
organizational culture
workgroup
efficiency
bail
judicial interim release
remand
adjournment
surety
conditions of release
youth
Youth Criminal Justice Act
Advisor: Doob, Anthony N.
Interrogation of Glioma Ontogeny using Mouse Models

Glioblastoma Multiforme (GBM) is the most common and lethal of human primary central nervous system tumours, with a median survival of 14-16 months despite surgery, radiation and chemotherapy. A reason for this dismal prognosis is insufficient understanding of the ontogeny of GBMs, which are highly heterogeneous at a pathological level. This pathological diversity, between and within GBMs as well as varying grades of gliomas, is not fully explained on the grounds of an oncogenic stimulus. Interaction with the tumour microenvironment, as well as inherent characteristics of the tumour cell of origin are likely a source of this heterogeneity. In this thesis we describe the use of a novel mouse model which integrates Cre-Lox mediated and Tet-regulated gene expression. This system in combination with germline and somatic strategies has enabled us to interrogate how the state in glial development and the region in the brain where transformation occurs influence the process of gliomagenesis. The findings of this thesis suggest that the state of glial development at which a mutation is introduced is an important determinant of gliomagenesis. In support of this, we showed that early progenitors in the radial glial lineage are more susceptible to transformation than those, which have committed to a gliogenic lineage and are presumably further along in the process of differentiation. Highlighting the interplay between genetic alterations and the molecular changes that accompany the process of differentiation. Despite findings that suggest that neurogenic regions of the adult brain are more susceptible to transformation, we show that this is not always the case and instead, transformation is dependent on an interaction between specific combinations of genetic mutations and susceptible cell types regardless of the region of origin. Results from this thesis highlight the need to view the tumourigenic process of gliomas in the context of normal brain development as the cell context of oncogene expression may determine the phenotype and biologic aggressiveness of the tumour. Thus, the results of genetic or epigenetic alterations leading to brain tumours may be quite different in different cells of the hierarchy, suggesting unique treatment targets and strategies depending on the cell of origin.

Keywords: Gliomas
Mouse models
Advisor: Guha, Abhijit
McGlade, Jane
The Distribution of Values of Logarithmic Derivatives of Real L-functions

We prove in this thesis three main results, involving the distribution of values of L′/L(σ,χ D), D being a fundamental discriminant, and χ D the real character attached to it. We prove two Omega theorems for L′/L(1,χ D), compute the moments of L′ /L(1,χD) and construct, under GRH, for each σ > 1/2, a density function [special characters omitted]σ such that #{D fundamental discriminants, such that |D| ≤ Y, and α ≤ L′/L(σ,χ D) ≤ β}[special characters omitted].

Keywords: logarithmic derivatives
L-functions
Advisor: Murty, V. Kumar
Becoming a Sustainability Chef: An Empirical Model of Sustainability Perspectives in Educational Leaders

This dissertation reports a study exploring adult engagement with sustainability learning practices in EcoSchools-certified secondary schools in Canada, Lithuania and Sweden as a means towards shaping a liveable future. The study is situated in the area of education for sustainable development. The study design was initially based on an interest in revealing specific practices of sustainability education as a means of improving the relationship between environmental impact and wealth. While echoing findings in the existing literature, this research contributes to the development of the field through insight into the perspectives that adults bring to sustainability education. Primary data collected in the spring of 2006 were recorded (mostly single) semistructured interviews with 30 individuals (national coordinators, caretakers, teachers and administrators), including 10 Canadians from four schools, 14 Lithuanians from four schools, and six Swedes from two schools. Four phases of qualitative analysis were used on the data: initial transcript coding and trends; précis document trends; a six-stage model of interview responses allowing vertical (between question) and horizontal (between stage) comparisons; word maps of subthemes as a scaffold to detail participants’ four primary views (long, wide, deep, dynamic) regarding sustainability. Ultimately, the results of this study point less than expected to revealing specific transferable practices regarding success and challenge in EcoSchools. Rather, these findings provide some insight into a means of shaping a sustainable future through an individual’s sustainability perspective: a living responsiveness based on a sense of connection, supported by improved sustainability cognition, and realized through sustainability practice and considered engagement.

Keywords: education for sustainable development (ESD)
sustainability learning
environmental education
sustainability practice
EcoSchools
educators' perspectives
Advisor: Thiessen, Dennis
Machine Learning for Aerial Image Labeling

Information extracted from aerial photographs has found applications in a wide range of areas including urban planning, crop and forest management, disaster relief, and climate modeling. At present, much of the extraction is still performed by human experts, making the process slow, costly, and error prone. The goal of this thesis is to develop methods for automatically extracting the locations of objects such as roads, buildings, and trees directly from aerial images. We investigate the use of machine learning methods trained on aligned aerial images and possibly outdated maps for labeling the pixels of an aerial image with semantic labels. We show how deep neural networks implemented on modern GPUs can be used to efficiently learn highly discriminative image features. We then introduce new loss functions for training neural networks that are partially robust to incomplete and poorly registered target maps. Finally, we propose two ways of improving the predictions of our system by introducing structure into the outputs of the neural networks. We evaluate our system on the largest and most-challenging road and building detection datasets considered in the literature and show that it works reliably under a wide variety of conditions. Furthermore, we are releasing the first large-scale road and building detection datasets to the public in order to facilitate future comparisons with other methods.

Keywords: machine learning
remote sensing
neural networks
Advisor: Hinton, Geoffrey
Toward a Holistic Pedagogy of Art Integration

As a conceptual study, this thesis aims to establish a holistic pedagogy of art integration that would address nurturing the whole child as the goal of education. Over the last few decades, art integration has become an important academic issue in curriculum studies, particularly at the early and primary levels of childhood education. Many have entertained various modes of art integration to promote their personal or institutional philosophies and goals of schooling. As a result, we see some popular arts-integrated programs which can be characterized as ‘interdisciplinary,’ ‘cognitive,’ ‘social,’ or ‘cultural.’ Those programs and approaches suggest, in one way or another, that there are good reasons why we need to be more active in including the arts into curriculum. Our schools would be better off with a well-thought-out arts-integrated curriculum. In this movement, however, there is a critical problem: many have come to believe that the arts are useful in so far as they are good for brain development and academic improvement. This mechanistic or cause-effect view of the relevance of the arts to education has gained solid support and is becoming the major focus when teachers and schools try to integrate the arts into their curricula. Facing this situation, this study proposes a holistic pedagogy of art integration through 1) refining the holistic curriculum with the help of process thought, 2) conceptualizing natural spirituality and its relevance to the whole child, 3) establishing the holistic ways of doing the arts in curriculum, 4) building holistic models of art integration, and 5) discussing some working programs and designing one that best exemplifies the holistic models. The holistic pedagogy of art integration to be established in this study is, then, intended to be one that would remedy some critical issues like reductionism and dualism engrained in the conventional view of art integration that currently dominates our school culture. The holistic ways of the arts developed in this thesis are suggested as one of the more promising ways of transforming our schools into learning and caring communities where our children will have a better chance to thrive as ‘whole persons.’

Keywords: arts-integrated curriculum
holistic education
Advisor: Miller, John P.
Low-cost Data Analytics for Shared Storage and Network Infrastructures

Data analytics used to depend on specialized, high-end software and hardware platforms. Recent years, however, have brought forth the data-flow programming model, i.e., MapReduce, and with it a flurry of sturdy, scalable open-source software solutions for analyzing data. In essence, the commoditization of software frameworks for data analytics is well underway. Yet, up to this point, data analytics frameworks are still regarded as standalone, em dedicated components; deploying these frameworks requires companies to purchase hardware to meet storage and network resource demands, and system administrators to handle management of data across multiple storage systems. This dissertation explores the low-cost integration of frameworks for data analytics within existing, shared infrastructures. The thesis centers on smart software being the key enabler for holistic commoditization of data analytics. We focus on two instances of smart software that aid in realizing the low-cost integration objective. For an efficient storage integration, we build MixApart, a scalable data analytics framework that removes the dependency on dedicated storage for analytics; with MixApart, a single, consolidated storage back-end manages data and services all types of workloads, thereby lowering hardware costs and simplifying data management. We evaluate MixApart at scale with micro-benchmarks and production workload traces, and show that MixApart provides faster or comparable performance to an analytics framework with dedicated storage. For an effective sharing of the networking infrastructure, we implement OX, a virtual machine management framework that allows latency-sensitive web applications to share the data center network with data analytics through intelligent VM placement; OX further protects all applications from hardware failures. The two solutions allow the reuse of existing storage and networking infrastructures when deploying analytics frameworks, and substantiate our thesis that smart software upgrades can enable the end-to-end commoditization of analytics.

Keywords: computer science
software
data analytics
data centers
Advisor: Amza, Cristiana
Pedagogy of Mythos

This work is a philosophical examination of the relevance and function of socio-political myths in education. Central to this work is exploring the antinomy between myth and reason. Drawing on the work of philosopher Hans Blumenberg, I defend his view that one should go beyond the myth and reason antinomy and understand myth as an important and unique mode of symbolic orientation that, along with reason and science, is an essential part of humanity’s symbolic interaction with the world. From this view, I explore how socio-political myths are philosophically and practically relevant to the analysis of society in general and education specifically. Of particular importance, I argue that a philosophical understanding of ‘socio-political myth’ should be integrated as part of the critical democratic conception of education. By integrating a substantive philosophical understanding of socio-political myths into the critical democratic framework, a number of important pedagogical implications are revealed. Specifically, this work reveals how two particularly powerful socio-political myths that are currently embedded in the Canadian education system, the meritocratic and neoliberal myths, ultimately erode and undermine values, beliefs and educational practices that are consistent with democracy. In addition, I contend that socio-political myth should be understood as an important and necessary narrative corollary to critical democratic praxis. As such, I conceptualize and defend what I denote as democratic myth as an essential narrative to the development of critical participatory democracy both in and through education. Finally, I conclude this work by examining how democratic myth may be practically developed by teachers and students.

Keywords: education
philosophy
democracy
myth
neoliberalism
meritocracy
Advisor: Portelli, John P.