VictorJuiz/thesis huggingface dataset:
Chldren's Ideas About Climate Change

This thesis examines children’s (aged 11-12) ideas about climate change. Seventh grade children in 9 schools in Ontario were interviewed and submitted illustrated responses about climate change over a one year period of data collection. Qualitative grounded theory was used to allow themes from the data to emerge, and the use of computer software, NVivo7, was used to code and classify themes. The data were analyzed to answer three main research questions. First, the thesis explored if there were common similarities or differences between the children’s and adults’ responses (as gained from the literature). Second, children’s responses were grouped by geographical location. These locations included rural, urban, and suburban school. This was conducted in order to determine if any group differences exist among children in these three areas. The study found that children’s and adults perceptions are quite similar, and that in some situations, both groups tend to use substitution of other environmental knowledge (cultural models) in lieu of knowledge of climate change but that children also tended to use different cultural models to explain their ideas about climate change. The thesis concluded that no group differences existed among rural, urban, and suburban children and children in all groups tended to have much more detailed knowledge of mitigation strategies than the effects and causes of climate change. The thesis also concluded that a new educational framework, modeled after the Causes, Effects, and Mitigation Strategies of Climate Change (CEM Framework) ought to be used to redistribute this knowledge across these three areas.

Keywords: Climate Change
Perceptions
Children
Advisor: Gough, William A.
Nonlinear Multicontrast Microscopy for Structural and Dynamic Investigations of Myocytes

Abstract: Nonlinear multicontrast microscopy is established in this study as an important tool for understanding biological structure and function of muscle cells. Second harmonic generation, third harmonic generation and multi-photon excitation fluorescence are acquired simultaneously in order to establish the origin of nonlinear signal generation in myocytes, and investigate myocyte structure and functionality during muscle contraction. Using structural cross-correlation image analysis, an algorithm developed specifically for this research, for the first time, third harmonic generation is shown to originate from the mitochondria in myocytes. The second harmonic, which is generated from the anisotropic bands of the sarcomeres, is further shown to be dependent on the crystalline order of the sarcomeres, thereby providing a potential diagnostic tool to evaluate disorder in muscle cells. The combination of the second and third harmonic provides complementary information that can be used to further elucidate the basic principles of muscle contraction. Time-lapse nonlinear microscopic imaging showed structural and functional dynamics in the myocytes. The second harmonic contrast revealed nonsynchronized nanocontractions of sarcomeres in relaxed, non-contracting, cardiomyocytes and Drosophila muscle samples, providing insight into the asynchronous behaviour of individual sarcomeres. Furthermore, macrocontracting samples were found to exhibit a synchronization of nanocontractions, providing new evidence for how muscles contract. Dynamic image correlation analysis, another algorithm developed specifically for this investigation, is used to reveal networks of mitochondria, which show fluctuations of multi-photon excitation fluorescence and third harmonic generation signals. The intensity fluctuations in the networks reveal both slow and fast dynamics; phase shifts of the slow dynamics between different networks are observed. Fast dynamics appear only in the inner networks, suggesting functional difference between interfibrillar and subsarcolemma mitochondria. The groundwork for studying bioenergetics of mitochondria in cardiomyocytes with nonlinear multimodal microscopy is fully developed in this work. The origin of the nonlinear signals and the development of the image analysis techniques provide a solid foundation to further study of muscle contractility and bioenergetics.

Keywords: nonlinear microscopy
biological imaging
harmonic generation
multi-contrast microscopy
Advisor: Barzda, Virginijus
Examining Different Levels of Prevention of Birth Defects and Fetal Alcohol Spectrum Disorder

While all women hope to deliver a healthy baby, approximately 3-5% babies are affected by birth defects. Birth defects can occur naturally or be induced by teratogens. Alcohol is a known teratogen that causes fetal alcohol spectrum disorder (FASD), the most commonly known cause of neurobehavioural and neurodevelopmental deficits. Individuals affected with FASD are likely to be involved with or require additional assistance from healthcare, education, social services, and justice sectors. Due to this immense burden, effective prevention of FASD can have a major public impact. Prevention of FASD can occur at different levels: primary prevention (preventing alcohol-induced birth defects from occurring in the first place); secondary prevention (preventing alcohol-induced birth defects from developing or progressing); tertiary prevention (improving the outcome of individuals affected with FASD); and quaternary prevention (preventing another child from being affected with FASD). The objective of this thesis was to explore a multilevel birth defect and FASD prevention strategy. Primary prevention by was investigated by maternal multivitamin supplementation to optimize fetal growing conditions, as alcoholics are commonly deficient in nutrients. A meta-analysis of maternal multivitamin supplementation demonstrated a decreased risk for certain congenital anomalies and pediatric cancers. Secondary prevention was investigated by a randomized double-blinded placebo-controlled evaluating the ability of high doses of antioxidants (vitamin C and vitamin E) to mitigate the effects of prenatal alcohol exposure. The study was ceased due to safety concerns regarding high doses of vitamin C and vitamin E in preeclamptic studies. Tertiary prevention was investigated by anonymous meconium screening of babies of Grey-Bruce, Ontario residents delivering at or transferred to St. Joseph’s Health Care in London, Ontario. A 30% prevalence of fatty acid ethyl esters (FAEE) positive meconium was observed at this high-risk unit. Meconium screening is also a means of quaternary prevention since positive screens also identify mothers who were unable to stop consuming alcohol after 13 weeks of pregnancy, and therefore are at risk of delivering another child who is prenatally exposed to alcohol. The identification and engagement of these mothers into treatment programs constitutes primary prevention of FASD in subsequent pregnancies.

Keywords: prevention
fetal alcohol spectrum disorder
birth defects
multivitamin
pregnancy
meconium
fatty acid ethyl esters
screening
Advisor: Koren, Gideon
On Load Balancing and Routing in Peer-to-peer Systems

A peer-to-peer (P2P) system is a networked system characterized by the lack of centralized control, in which all or most communication is symmetric. Also, a P2P system is supposed to handle frequent arrivals and departures of nodes, and is expected to scale to very large network sizes. These requirements make the design of P2P systems particularly challenging. We investigate two central issues pertaining to the design of P2P systems: load balancing and routing. In the first part of this thesis, we study the problem of load balancing in the context of Distributed Hash Tables (DHTs). Briefly, a DHT is a giant hash table that is maintained in a P2P fashion: Keys are mapped to a hash space I --- typically the interval [0,1), which is partitioned into blocks among the nodes, and each node stores the keys that are mapped to its block. Based on the position of their blocks in I, the nodes also set up connections among themselves, forming a routing network, which facilitates efficient key location. Typically, in a DHT it is desirable that the nodes' blocks are roughly of equal size, since this usually implies a balanced distribution of the load of storing keys among nodes, and it also simplifies the design of the routing network. We propose and analyze a simple distributed scheme for partitioning I, inspired by the multiple random choices paradigm. This scheme guarantees that, with high probability, the ratio between the largest and smallest blocks remains bounded by a small constant. It is also message efficient, and the arrival or departure of a node perturbs the current partition of I minimally. A unique feature of this scheme is that it tolerates adversarial arrivals and departures of nodes. In the second part of the thesis, we investigate the complexity of a natural decentralized routing protocol, in a broad family of randomized networks. The network family and routing protocol in question are inspired by a framework proposed by Kleinberg to model small-world phenomena in social networks, and they capture many designs that have been proposed for P2P systems. For this model we establish a general lower bound on the expected message complexity of routing, in terms of the average node degree. This lower bound almost matches the corresponding known upper bound.

Keywords: peer-to-peer
load balancing
routing
Advisor: Hadzilacos, Vassos
User Interfaces for Visual Search

Visual search is an important component of many human-computer interactions and a critical task in a variety of domains. These include screening for prohibited items in x-ray imagery of luggage in airports, identifying anomalies in medical imagery, and looking for unusual activity and changes over time in satellite imagery. Unlike many other human-machine interface tasks where a small error rate is quite acceptable, a crucial element of visual search tasks in these application areas is that a single mistake can have catastrophic consequences. Thus, any improvements in technology, interfaces, or human processes that can be made to aid visual search would be invaluable in these safety critical areas. Furthermore, even when one does not consider consequential activities such as cancer screening and airport security, most human-computer interactions involve some search component, and the impact of even small improvements is magnified by a high frequency of use. This thesis explores how some of these issues affect individuals' and teams' ability to perform visual searching tasks. Considerations such as group size and display configuration are examined, as are novel interfaces that aid search on tabletop and wall displays. The overarching goal of this work is to provide system designers with immediately implementable advice and guidelines on how to improve their systems in respect to visual search and to outline further research in this critical area.

Keywords: Visual Search
Human Computer Interaction
User Interface Design
Displays
Advisor: Balakrishnan, Ravin
The Study of Interfacial Dynamics at Biochemically Modified Surfaces Using Acoustic Wave Physics and Molecular Simulations

Detection of conformational and structural shifts in biomolecules is of great importance in bioanalytical chemistry and pharmaceutical sciences. Transverse shear mode acoustic wave devices have been used as real-time, label-free detectors of conformational shifts in biomolecules on surfaces. However, material changes in the biochemical monolayer and coupling between the substrate and the surrounding liquid make it difficult to isolate the desired signal, so an understanding of these phenomena is required. In this thesis, interfacial slip, viscoelasticity, and structural changes are used to model acoustic signals due to surface adsorption of the protein neutravidin, immobilisation of HIV-1 TAR RNA, and subsequent interaction of the RNA with tat peptide fragments. Binding of tat peptides induces conformational changes in the TAR. Similar modelling is performed to describe experiments involving the binding of calcium to surface-attached calmodulin, which is also known to result in a conformational shift. The aim of the modelling is to isolate the sensor response due to conformational shifts. The biomolecules are described as hydrated, viscoelastic monolayers and slip is allowed at all interfaces. All models are numerically fit to experimental values using a two-parameter minimisation algorithm. Slip is found on the electrode surface prior to neutravidin adsorption. Neutravidin and TAR are described as distinct viscoelastic monolayers. Binding of tat peptide fragment to the TAR monolayer is modelled using a complex slip parameter and a change in length, corresponding to a straightening of the molecule. Similarly, numerical modelling of calmodulin results reveals a length change in the molecule upon calcium binding. Molecular dynamics (MD) simulations of the TAR-tat fragment system are performed to corroborate the modelling results. Starting structures are computed by molecular docking, and MD simulations of TAR complexed with various length tat fragments are described. The simulations are in general agreement with the modelling results and literature values from similar molecular dynamics experiment. A new parameter is introduced to describe biomolecule-solvent affinity, and is compared to interfacial coupling values obtained from modelling. This research demonstrates that acoustic wave devices can be used to detect conformational shifts in surface-attached biomolecules, provided molecular details about the shifts are known.

Keywords: Biosensors
Acoustic wave device
bioanalytical chemistry
interfacial fluid dynamics
slip
Advisor: Thompson, Michael
The Leadership Practices of Nurse Managers and the Association with Nursing Staff Retention and the Promotion of Quality Care in Two Saskatchewan Hospitals

Abstract The leadership practices of nurse managers and the association with nursing staff retention and the promotion of quality care in two Saskatchewan hospitals? Doctor of Philosophy, 2009, Karen Eisler Graduate Department of Faculty of Nursing, University of Toronto The purpose of this descriptive correlational study was to explore the relationship between nurse managers’ leadership practices as measured by Kouzes and Posners’ (2001) Leadership Practice Inventory and staff nurses’ intent to leave the job, absenteeism, medication errors and the quality of care. A total of 450 RNs and LPNs responded to a mailed survey. The respondents were representative of the target population; 54% were 46 years of age or older, 81% RNs and 19% LPNs, 95% female, over 65% had at least 11 years of nursing experience, and 65% worked fulltime. Staff nurses gave low ratings of their managers’ use of the five transformational leadership practices. There was a weak or non significant relationship between the five leadership practices and staff nurses’ intent to leave, absenteeism or medication errors. Results of hierarchical multiple regression analyses revealed that some of the leadership practices had a significant positive relationship with perceived quality of patient care and nursing care on the unit. The strongest predictors of quality of patient care (23% of the variance) were the leadership practices, Challenge the process, Inspire a shared vision, Enable others to act and Model the way. The strongest predictors of the quality of nursing care (16% of the variance) were the leadership practices, Model the way and Challenge the process. The results of this study indicated that managers’ use of transformational leadership practices can affect the staff nurses’ perception of the quality of patient care and nursing care on a unit. It is important that nurse managers develop leadership practices to promote high quality care in Saskatchewan hospitals.

Keywords: nursing leadership
nurse manager
Advisor: O'Brien-Pallas, Linda
Development and Evaluation of Whole Slide Hyperspectral Confocal Fluorescence and Brightfield Macroscopy

Microscopic imaging in the biomedical sciences allows for detailed study of the structure and function of normal and abnormal (i.e., diseased) states of cells and tissues. The expression patterns of proteins and/or physiological parameters within these specimens can be related to disease progression and prognosis, and are often heterogeneously spread throughout the entire specimen. With conventional microscopy, a large number of individual image ‘tiles’ must be captured and subsequently combined into a mosaic of the entire specimen. This has the potential to introduce artefacts at the image seams, as well as introducing non-uniform illumination of the entire specimen. A further limitation often encountered in biomedical fluorescence microscopy is the high background due to the autofluorescence (AF) of endogenous compounds within cells and tissues. Often, AF can prevent the detection and/or accurate quantification in fluorescently- labelled tissues and, in general, can reduce the reliability of results obtained from such specimens. AF spectra are relatively broad and so can be present across a large number of image spectral channels. The intensity of AF also increases as the excitation wavelength is decreased, causing increasing amounts of autofluorescence when exciting in the blue and near-UV range of the spectrum (400 - 500 nm). This thesis reports the development of hyperspectral, fluorescence and brightfield imaging of entire, paraffin-embedded, formalin-fixed (PEFF) tissue slides using a prototype confocal scanner with a large field of view (FOV). This technology addresses the challenges of imaging large tissue sections through the use of a telecentric f-theta laser scan lens thus allowing an entire microscope slide (22x70 mm) to be imaged in a single scan at resolution equivalent to a 10x microscope objective. The development and optimization of brightfield and single-channel fluorescence imaging modes are discussed in the first half of this thesis, while the second half and appendices concentrate on the spectral properties of the system and removal of AF from PEFF tissue sections. The hyperspectral imaging mode designed for this system allows the fluorescence emission spectrum of each image pixel to be sampled at 6.7 nm/channel over a spectral range of 500-700 nm. This results in the ability to separate distinct fluorescence signatures from each other, and enables quantification even in situations where the AF completely masks the signal from the applied labels.

Keywords: hyperspectral
fluorescence
confocal
autofluorescence
linear unmixing
multi channel
pathology
tissue imaging
microscope
macroscope
Advisor: Brian, Wilson
The Anthropomorphization of Law: Fictional Judges and Lawyers in Contemporary North American and European Settings

This dissertation examines the varying roles of lawyers and judges in Canada, the United States, England, France and Germany in a selection of “fictional legal narratives”: novels, movies, television shows and plays that explore legal themes. The study focuses on contemporary works after 1960, and explores the North American fascination with lawyers that saturates the major levels of culture, from the popular (including television shows, movies and novels) to the academic. Fictional images of lawyers and judges not only reflect but arguably also influence our attitudes toward the legal system, and offer a concrete way of conceptualizing abstract legal concepts. However, the vast differences between the Anglo-American adversarial legal system and the continental European inquisitorial legal system spawn very different fictional portraits of lawyers and judges. The differences between fictional legal narratives produced by each country, even those with similarly structured legal systems, are also striking. Chapter One begins by outlining a number of factors that contribute to the proliferation of fictional legal narratives in some countries, and their relative scarcity in other countries. Next, Chapter Two traces the wide range of lawyer images in American fictional legal narratives, which both glamourize and demonize the figure of the lawyer. Turning to anthropomorphizations of law in the United Kingdom, Chapter Three examines the British tendency to perpetuate the idea that, if correctly executed, the fundamental principles of British law would lead to a just and harmonious society. Chapter Four then explores the “anxiety of influence” reflected in Canadian images of law, which are more “soft-boiled” than the fictional legal figures of other countries. Moving to French fictional legal narratives, Chapter Five contemplates the predominance of the juge d’instruction figure and the prevalence of the investigatory mode. The dissertation then discusses the relative scarcity of fictional legal narratives in Germany, and the cynicism in existing German stories about law in Chapter Six. The study concludes by considering the future directions of the law and culture movement, as well as both the challenges and rewards of this interdisciplinary work.

Keywords: (Treatment of) Law
Lawyer
Judge
Law and Literature
Advisor: Hutcheon, Linda
Exploration of Autobiographical, Episodic, and Semantic Memory: Modeling of a Common Neural Network

The purpose of this thesis was to delineate the neural underpinning of three types of declarative memory retrieval; autobiographical, episodic, and semantic. Autobiographical memory was defined as the conscious recollection of personally relevant events, episodic memory as the recall of stimuli presented in the laboratory, and semantic memory as the retrieval of factual information and general knowledge about the world. Young adults participated in an event-related fMRI study in which pictorial stimuli were presented as cues for retrieval. By manipulating retrieval demands, autobiographical, episodic, or semantic memories were extracted in response to the same stimulus. The objective of the subsequent analyses was threefold: firstly, to delineate regional activations common across the memory conditions, as well as neural activations unique to each memory type (“condition-specific”); secondly, to delineate a functional network common to all three memory conditions; and, thirdly, to delineate functional network(s) of brain regions that show condition-specific activity and to assess their overlap with the common functional network. The results of the first analysis showed regional activations common to all three types of memory retrieval in the bilateral inferior frontal gyrus, left middle frontal gyrus, right caudate nucleus, bilateral thalamus, left hippocampus, and left lingual gyrus. Condition-specific activations were also delineated, including medial frontal increases for autobiographical, right middle frontal increases for episodic, and right inferior temporal increases for semantic retrieval. The second set of analyses delineated a functional network common to the three conditions that comprised 21 functionally connected neural areas. The final set of analyses further explored the functional connectivity of those brain regions that showed condition-specific activations, yielding two functional networks – one involved semantic and autobiographical conditions, and the other involved episodic and autobiographical conditions. Despite their recruiting some brain regions unique to the content of retrieved memories, the two functional networks did overlap to a degree with the common functional network. Together, these findings lend support to the notion of a common network, which is hypothesized to give rise to different types of declarative memory retrieval (i.e., autobiographical, episodic, or semantic) along a contextual continuum (i.e., highly contextualized or highly decontextualized).

Keywords: declarative memory
neural networks
Advisor: Grady, Cheryl L.