VictorJuiz/thesis huggingface dataset:
Establishing Geometallurgical Relationships between Rock Comminution Behaviour and Rapid and Portable Drill Core-Scale Rock Characterization Tests
Keywords: Data Science
Geomechanics
Geometallurgy
Mineral Processing
Numerical Modelling
Rock Characterization

Rock comminution is an energy-intensive process contributing to cost uncertainty in mining. Expensive and time-consuming comminution testing leads to insufficient characterization of orebody variability, which can result in significant fluctuations in energy consumption. Rapid and portable drill core-scale rock characterization is a practical geometallurgical proxy for comminution testing, but linking the two types of tests requires understanding how rock properties on different scales influence comminution behaviour. The three studies of this research investigate the effect of rock macro- and micro- properties on comminution breakage and energy consumption to establish geometallurgical relationships between rapid and portable rock characterization tests on the drill core-scale and comminution behaviour.The first study applies data analytics to identify relationships between Bond work index (BWI) and rock characterization data for the Paracatu orebody. The regolith and fresh rock geometallurgical domains are established from unsupervised learning. Regolith weathering creates a strong relationship between BWI and physicomechanical properties. Supervised BWI classification in the fresh rock identifies the greater importance of geochemical properties. The second study integrates geometallurgical characterization and data analytics for the Tasiast orebody to understand what rock macro- and micro- properties influence grinding and evaluate rock characterization test proxies for BWI. Texture and geochemistry are identified as significant predictors for discriminating lower BWI clastic-derived and higher BWI crystalline-derived samples. Portable X-ray fluorescence analysis is determined as an effective rapid and portable rock characterization test for BWI modelling at Tasiast. The third study employs the discrete element method to investigate the influence of rock foliation on jaw crushing behaviour by parametrically varying geometrical and strength properties of anisotropic planes in bonded particle models during crushing simulations. Varying these properties can inhibit or facilitate fracture propagation in the model, resulting in a demonstrable variability in its matrix breakage evolution and energy input. This research signifies that drill core-scale rock characterization tests can be used to predict comminution indices when variability in drill core-scale rock properties are linked to variability in rock properties dictating resistance to comminution loading. This enables these tests as practical geometallurgical tools in forecasting feed variability to the comminution circuit for control energy consumption.
Sustainable Valorization of Steelmaking Slag: From Metal Extraction to Carbon Sequestration
Keywords: Carbon sequestration
Carbonation
Extractive metallurgy
Resource recovery
Steelmaking slag
Waste valorization

This dissertation is focused on the development of novel, effective, and environmentally sustainable processes for the recovery of critical metals such as niobium, titanium, and magnesium from steelmaking slag and carbon dioxide (CO2) sequestration using steelmaking slag. In this work, a fundamental understanding of the metal extraction process and carbonation process was developed using principles of reaction kinetics, mass transfer, and thermodynamics to elucidate the underlying physicochemical mechanisms. This approach helps tackle the sustainability challenges associated with the supply of such materials, reduce the carbon footprint attributed to the steelmaking industry, and unveil the hidden value of industrial wastes. In this dissertation, innovative pyro-hydrometallurgical processes were developed for the recovery of valuable components, i.e., niobium, titanium, and magnesium, from steelmaking slag. In this work, the physicochemical mechanisms of this process and their consequences on the process efficiency and operation of the process were investigated. The process mechanism was validated by trials using synthetic analogues to steelmaking slag, phase identification, morphology characterization, elemental mapping measurements, and microstructure measurements. The focus of this dissertation was expanded to the development of a novel supercritical carbonation process for CO2 sequestration using EAF slag. A systematic design of experiments and response surface methodology were used to develop a model for calculating the carbonation efficiency as a function of various operating parameters, such as slag particle size, CO2 pressure, reaction temperature, water to slag ratio, and processing time. It was demonstrated that the empirical model built in this work is suitable for process optimization with the objective of maximizing the CO2 uptake of the slag. On the basis of the fundamental investigations, it was identified that the diffusion barrier to the carbonation process is a product calcium carbonate layer formed on the outer shell of the slag particle and the thickness of this layer is constant regardless of the slag particle size. It is believed that the knowledge gained here will help enable the development of robust, cost-effective, and efficient pyro-hydrometallurgical processes for the valorization of industrial process residues, alongside the development of novel and environmentally-friendly supercritical carbonation processes for CO2 sequestration using industrial wastes.
“Some people get lost”: A Practitioner Inquiry into the Transnational, Diasporic, and Educative Experiences of Participants in an After School Reading and Writing Group
Keywords: Critical Literacy
Disability Studies
Education
Poetry
Practitioner Research
Writing Pedagogy

This practitioner research study documents the experiences and perspectives of nine Academic Upgrading students in an After School Reading and Writing Group who were enrolled within an urban college in Toronto. The group is composed of multilingual participants who count among their primary or secondary languages: Arabic, Bajan (A variation of West African Creole), Dhalik, English, Tigrinya, Spanish, and Urdu. These students were placed within an Academic Upgrading program to improve their literacy skills with the hopes of attaining entrance into the mainstream college. Drawing inspiration from practitioner research studies that intentionally research and “teach against the grain” (Cochran-Smith Lytle, 2009, p. 23), the After School Reading and Writing Group co-selected diasporic literature. Through discussions and writing, members recounted their own complex engagements across cultural, linguistic, and educational contexts. This research explores what happens when students narrate their own educational histories in a literary discussion group with texts that offer them an opportunity to explore the intersections between migration, race, power, identity, and schooling. I locate this work within the research on out-of-school literacies (Bronkhorst Akkerman, 2016; Hull Schulz, 2002), critical literacy (Duncan-Andrade, 2007b; Freire Macedo, 1987; Morell, 2009) and counternarratives of schooling (Delgado, 1995; Ladson-Billings, 1998; Sandoval, 2000). I document central tensions that influenced members’ educational histories and trajectories. These include literacy shaming, language policing, racial discrimination, the medical model of disability, and academic assumptions about what they could and could not accomplish. Findings surface the complexity of the group’s engagements with texts, the internalized deficit perspectives that often haunt their writing, the compulsion and reluctance to share vulnerable stories—their struggle to see themselves as legitimate writers with authorial voices. This study has implications for practitioners, policymakers, and researchers concerned with deepening understandings of teaching writing and reading to academically marginalized students.
The struggle for urban resources in Sao Paulo, Brazil: How can the housing movement tackle urban health inequities?
Keywords: Decolonization
Health equity
Housing
Social justice
Social movements
Urban health

The economic, social and health benefits arising from the process of urbanization and globalization have been unevenly distributed within cities, benefiting some social groups to the detriment of others, some neighbourhoods at the expense of others and contributing to the growth of pockets of wealth and poverty characterized by inequitable distribution of income and essential urban health resources. Over the last few decades, there has been an emergence and consolidation of the housing movement in Sao Paulo, Brazil, leading groups of citizens to articulate their struggle for social and housing justice and access to urban land, housing and basic infrastructure for the most marginalized groups. Drawing on critical theory of health inequities and decolonial thought, this dissertation employs a critical ethnography lens to examine how the housing movement in Sao Paulo addresses urban health inequities. In addition, this study aims to examine how members of the housing movement understand urban health inequities and what strategies they employ to address them. It also discusses what insights the housing movement generates to inform public health practice. Data was collected through participant observations of the housing movement’s meetings and events, individual interviews with 19 participants of the movement, a socio-demographic questionnaire, and go-along interviews. The study suggests that the housing movement has constituted itself as a credible participant in the process of resisting uneven urbanization and peripheralization of the urban poor. By combining different types of knowledge, expertise and resources with different actors and institutions, they influence national and local urban and housing policies that benefit socially disadvantaged groups. As a result, I argue that the housing movement is challenging urban health inequities and contributing to creating a healthier and more equitable society. Public health practitioners and the housing movement can work together to influence policies and programs that contribute to addressing the effects of urban inequities on the health of families and individuals living on the margins of unequal cities.
A Relational Approach to Regional Economic Development: Essays on Migration, Globalization, and Inequality
Keywords: globalization
housing
immigration
inequality
migration
regional economic development

The rise of economic populism and movements for greater racial, gender, and class equality over the last few years have foregrounded the massive problems of spatial and social inequality in the United States. Academic research focused on these disparities increasingly suggests that a mix of rising economic inequalities across the U.S. urban system, as well as inadequate attention to deep historical economic injustices, have eroded economic mobility for many people and places. Providing concrete solutions to this issue is a thorny problem for social science and policy which requires that we address inter-regional, intra-regional, and inter-personal inequalities, as well as their interconnections. The following chapters argue that a relational perspective of economic development – one that centers how the behaviors, interactions, and organization of economic actors shape economic development – is a fruitful way forward to understanding and mitigating these inequalities. Focusing on how globalization and emerging migration patterns shape and respond to actors’ (e.g. workers, firms, and other collective organizations) economic relations, the three papers in this thesis show how a relational approach to regional economic development can be employed to better understand inequality and opportunity for different people and places across the U.S. urban system.
Electrochemical Determination of Extracellular Phosphorylation in Neuronal and Neuroblastoma Cells
Keywords: Bio-electroanalytical sensors
Biosensor
Electrochemistry
Neuroblastoma
Neuron
Phosphorylation

This thesis describes the investigation, imaging and quantification of the extracellular membrane phosphorylation profiles of human neuron and neuroblastoma cells through the use of surface-based electrochemical sensors. This investigation started by demonstrating electrochemistry as a simple and effective technique to determine the phosphorylation state of neuronal proteins. The nAChR α7 subunit, an abundant and essential surface receptor protein, was used as an example protein and three important ectokinases, PKA, PKC and Src, were utilized to phosphorylate the protein. To confirm these results, gel electrophoresis and XPS studies were performed. Once establishing electrochemistry as a useful methodology, the next phase involves phosphorylating whole fixed neuronal cells and monitoring the phosphorylation profile of each of the three ectokinases described above. The electrochemical techniques were supplemented with fluorescence microscopy and quartz crystal microscopy (QCM). Fluorescence microscopy indicated that each of the kinase phosphorylation reactions had completed within 8 hours and QCM established that the number of phosphorylation sites for neuronal cells by PKA, PKC and Src were 5.7 x106 sites/cell, 5.3 x106 sites/cell, 4.8 x105 sites/cell, respectively. For neuroblastoma cells, the number of sites were determined be 1.1 x106 sites/cell, 1.1 x106 sites/cell and 7.4 x105 sites/cell. It is established that neuroblastoma cells differ significantly from neuronal cells in their extracellular phosphorylation states. Lastly, using the phosphorylation profiles, the percent composition of neuronal and neuroblastoma cells mixtures can be determined. Findings obtained from this thesis establish that mammalian neuronal cells (healthy) and neuroblastoma cells (cancerous/disease state) have different extracellular phosphorylation patterns. Furthermore, it is emphasized that electrochemical techniques provide insights for the design of new histological or diagnostic technology.
Why did Ecuador Adopt Education Standards and Citizenship Education? An Analysis through Four Different Theoretical Approaches
Keywords: Citizenship Education
Decolonial Thought
Ecuador
Education Standards
Global Education Policy
Policy Borrowing

This research consists of an exploration of the reasons why Ecuador adopted two policies (education standards in 2013 and citizenship education in 2011) through four different theoretical approaches: rationalism, world culture theory, culturalism and decolonial thought. This study uses an adaptation of the Comparative Case Study Approach (Bartlett Vavrus, 2017) and the data consists of 25 interviews of organizational elites as well as 80 documents. In answering the main research question, this study also explores voluntary choice versus coercion in reasons for policy adoption, showing there are more ways of exerting power in policy adoption than commonly shown in Global Education Policy literature. It also teases out what three main theoretical approaches in Global Education Policy illuminate/overlook in explaining policy adoption and brings a fourth theoretical approach into the conversation: decolonial thought. And so, why did Ecuador adopt education standards and citizenship education? I found three main answers: (1) an “official” answer - Ecuador adopted both policies to solve national problems (reflecting rationalism) with a countertheme to this, signaling that policy makers might also have adopted education standards for reasons of political expediency (reflecting culturalism), (2) a common answer - Ecuador adopted both policies due to international influence (reflecting world culture theory) with a counter theme highlighting policy makers’ emphasis on national sovereignty and their own agency as decision-makers (reflecting rationalism and culturalism) and (3) a decolonial theory answer - Ecuador adopted both policies because it is embedded in global hegemonic colonial power which includes power differentials between nation states, power differentials in knowledge, power differentials between racial groups, and the structures of internal colonialism. This study responds to three policy borrowing research needs: (1) the inclusion of more postcolonial/decolonial thought, (2) more policy borrowing studies reflecting societies of the Global South and (3) further study and theorization of the policy adoption phase. In addition, this study offers two theoretical contributions: (1) an adapted continuum of voluntary-coercive reasons for policy adoption and (2) a proposed conceptual framework for studying reasons for policy adoption.
Quantifying and Reducing Uncertainty in the Measurement of Health Utilities
Keywords: health utility
model misspecification
MSE
parameter uncertainty
sample size
spatial correlation

Health utilities, commonly used in health economic evaluations, are the quality weights used in estimating quality-adjusted life years, and can be measured using multi-attribute utility instruments (MAUI) like the EQ-5D-3L. Like other MAUIs, the EQ-5D-3L defines health states and utilities are assigned to each of these health states through a valuation study where typically a subset of the health states are valued. A regression model with state level covariates is fitted on the valuation study data and mean utilities are predicted for all the health states. Uncertainty in the estimation of these utilities may arise from several sources and model mis-specification error is one of the major sources, which is ignored in current practice. In previous literature, addition of a mis-specification error in the model has been suggested, though these errors were assumed to be independent. Health states of a similar severity may have similar utilities and hence mis-specification errors can be assumed to be correlated. The focus of this thesis was two fold. First, I explored different modeling techniques considering different correlation structures on the mis-specification error in order to reduce the level of uncertainty. Second, I derived a formula to check the predictive ability of a model in the presence of mis-specification error that will facilitate future researchers in designing a more efficient valuation study. A model with a Gaussian spatial correlation structure assumed on the mis-specification error was found to reduce the mean squared error (MSE) substantially in comparison to a model with an independent correlation. Furthermore, using the derived formula, some of the well known valuation study designs were compared. It was demonstrated that the MSE value that is achieved with a conventional study design can be achieved at a much lower sample size when mis-specification error is incorporated and spatial correlation is assumed which makes conducting a valuation study more feasible in resource constrained countries. These proposed methods not only result in health economic evaluations that are statistically sound by reducing the uncertainty in estimated health utilities but also ensures more efficient use of research resources by reducing the required sample size.
The Economic Effects of Transportation Policy
Keywords: Congestion charge
Urban economics

The Economic Effects of Transportation Policy a thesis submitted for the degree of Doctor of Philosophy and convocation year of 2021 by Ian Herzog to the Graduate Department of Economics in the University of Toronto. This thesis collects three papers discussing effects of transportation policy and infrastructure on neighbourhoods, cities, and regions. In each paper I combine new spatial data with economic theory to estimate how road pricing, traffic congestion, and road building affect economic wellbeing. In the first chapter, The City-Wide Effects of Tolling Downtown Drivers, I study the effects of London England's Congestion Charge on regional traffic, commuting, and economic activity's spatial distribution. I begin by showing that the policy reduced rush-hour traffic in the tolled downtown area and on radial roads leading downtown. I then use London's Congestion Charge as a natural experiment to find ensuing effects of traffic on commuting by car and public transit. These patterns calibrate a quantitative spatial model to conclude that London's Congestion Charge increases driving rates among untolled commuters and gives the region's commuters positive net benefits that disproportionately accrue to low-skill workers. In chapter two, The Marginal External Cost of Traffic in Greater London, I estimate the time costs of rush-hour road traffic in London England. To identify causal effects, I merge web-scraped travel times with Greater London's traffic monitoring network and compare across time of day at each road link. Results suggest that prevailing traffic conditions create a substantial deadweight loss, that driving downtown from the airport creates larger externalities than the average car commuter at the margin, and that public transit creates substantial congestion relief benefits. Chapter three, National Transportation Networks, Market Access, and Regional Economic Growth, steps back to estimate interregional transportation's effect on local economic activity by studying the Interstate Highway System. Using a new empirical strategy, I present evidence that through market access highways increased employment and had small and delayed wage effects. These patterns then calibrate a structural model to show that additions to early Interstate plans benefited places they cross but were less valuable than the system's core.