VictorJuiz/thesis huggingface dataset:
Constraints on maintaining groundwater recharge via stormwater infiltration

Conventional stormwater infiltration systems (SIF's) have historically been utilized in many jurisdictions as a means of maintaining groundwater recharge in urbanizing areas. In Ontario, concerns have been raised over the potential for aquifers to assimilate recharged waters, SIF sustainability and deterioration of groundwater quality from infiltration of urban runoff. To address these concerns a research study was undertaken involving an evaluation of SIF operations in a leading jurisdiction, hydrogeologic monitoring of six pilot SIF operations in Ontario, construction of a SIF laboratory model to observe clogging processes, 3-D groundwater flow modelling of SIF's in variable hydrogeological conditions and an evaluation of commonly applied analytical solutions for calculating the water table impact attributed to SIF operation. The results of these studies showed that when properly designed, SIF's can operate efficiently in a wide range of hydrogeological conditions and infiltration efficiency can be maintained by utilizing relatively simplistic maintenance measures.
Sulphur amino acid metabolism: an investigation of the requirements for methionine and cysteine and their metabolism in adult men

Methionine is an indispensable amino acid in humans. Its metabolism is characterized by a complex cycle that includes vitamin cofactor-dependent transmethylation, transsulfuration, and remethylation reactions. The current recommended dietary allowance (RDA) for total sulphur amino acids as methionine is based on nitrogen balance data that are widely believed to underestimate true requirements. The methionine requirement was estimated in adult males (n = 6) using graded intakes of methionine with no cysteine present in the diet. It was hypothesized that the methionine requirement estimated by partitioning the oxidation of phenylalanine to a two-phase linear regression analysis, whereby the intersection of the lines would be representative of the mean requirement, would be higher than the FAO/WHO/UNU published estimates for the methionine requirement. An oral isotope dosing protocol was used. The mean requirement was 12.6 mg·kg−1·d−1 and the corresponding RDA was determined to be 21 mg·kg−1 ·d−1. Using a similar design, the sparing effect of dietary cysteine on the methionine requirement was quantified. Healthy adult male volunteers (n = 6) were fed graded intakes of methionine and 21 mg·kg−1 ·d−1 of dietary cysteine. The mean methionine requirement was found to be 4.5 mg·kg−1·d −1 and the corresponding RDA was 10.1 mg·kg−1 ·d−1, representing a cysteine sparing effect of 64% on the mean methionine requirement in comparison to the previous study. To demonstrate a biochemical basis for cysteine sparing, the impact of dietary cysteine on rates of transsulfuration was assessed in healthy adult male volunteers (n = 5). Methionine cycle kinetics, including transsulfuration, were estimated using L-[1-13C, methyl -2H3]methionine. When the total sulphur amino acid content of the diet was equal to the RDA for total sulphur amino acids found in the first study, replacement of methionine by cysteine resulted in a significant reduction in transulfuration. The published RDA for total sulphur amino acids is 60% lower than the RDA defined here. Furthermore, data from this thesis confirms the existence of a cysteine sparing effect on methionine requirements in humans based on a suppression of transsulfuration by dietary cysteine.
An investigation of the endosomal trafficking of the ClC-2 chloride channel

The voltage-gated ClC-2 chloride channel has been functionally implicated in several physiological processes. First, ClC-2 knock-out mice are blind, and the males, infertile. Furthermore, a role for modulating neuronal ionic homeostasis has been proposed as mutations in ClC-2 are associated with epilepsy, and ClC-2 has been localized to the GABAergic synaptic locale in hippocampal neurons. Although the functional properties of ClC-2 have been extensively studied, less is known about the proteins and mechanisms that serve to regulate its function. The work presented here has made significant progress towards achieving a better understanding of how the vesicular trafficking of ClC-2 contributes to the modulation of its function. Using a combination of biochemical, physiological and cell biology techniques, we demonstrate that manipulations known to modulate ClC-2 channel function do so, in part, by altering its endosomal trafficking routes. Specifically, Calyculin A, which promotes protein phosphorylation, facilitates the internalization of ClC-2 in a dynamin-dependent manner, and ultimately leads to its proteasomal degradation. This retrograde pathway involves the dynein motor complex, which participates in a functional interaction with ClC-2. Conversely ATP depletion, a condition that promotes protein dephosphorylation, recruits intracellular ClC-2 to the cell surface in a Rab11-dependent pathway. Finally, we have found that ClC-2 is physically associated with the GABA A receptor in vivo. Our investigations suggest an extrasynaptic and possibly intracellular localization for this interaction, and provide the biochemical evidence to support a functional interaction between these two channels. We therefore propose that the endosomal trafficking of ClC-2 may play a significant role in the functional regulation of the GABA A receptor. Collectively, our findings underscore the physiological significance of the endosomal trafficking of ClC-2, and provide the structural framework for future studies aimed to determine the role of ClC-2 in endosomal function.
The post-surgical stability of Le Fort 1 maxillary impaction: a comparative study of titanium versus resorbable fixation

A resorbable copolymer (82% poly-L-lactic acid: 18% polyglycolic acid) has been investigated as a potential alternative to titanium for fixation of Le Fort 1 maxillary impaction. No study has examined the skeletal stability of this procedure when resorbable copolymer is used. Fifty consecutive patients underwent maxillary impaction by means of Le Fort I osteotomy. Twenty-five patients were treated with titanium fixation; 25 patients were treated with resorbable fixation. Lateral cephalograms were obtained 1 week preoperatively (T1), 1 week postoperatively (T2) and after a minimum of 8 months postoperatively (T3). Linear and angular measurements were recorded digitally to evaluate 2-dimensional skeletal change. Statistical analysis showed no significant radiographic differences (p < 0.05) in long-term stability within or between the two groups. No clinical or radiographic evidence of wound healing problems were noted. These results support resorbable copolymer fixation of Le Fort 1 impaction as a viable alternative to titanium fixation.
Perennial pedagogy

This is a qualitative study that explores the theoretical and practical foundation of an education that is grounded in the perennial understanding. The timeless and boundless perennial understanding, commonly known as 'the perennial philosophy' has been a part of the wisdom traditions for centuries. This philosophy can significantly contribute towards deeper and meaningful lives if brought into the educational milieu. This study is, therefore, an attempt to contribute to developing theories about holistic education, which has perennial philosophy as its philosophical underpinning, and to a growing but still partial understanding of the scope of the perennial philosophy within the educational environment. The study is carried out by examining how such a pedagogy would operate and what the pedagogical consequences for those involved and for society at large would be. In this work I will refer to such an education as 'perennial pedagogy'.
Magnetic-susceptibility-based functional MRI for heart disease

Heart disease is the primary cause of mortality in the western world. A common feature among several cardiac pathologies is the disruption of hemodynamic and/or oxygen metabolism/delivery homeostasis. The major hemodynamic variables of interest in the clinical assessment of heart disease are blood pressure and flow. While the noninvasive assessment of flow and systemic pressures are easily obtained, the measurement of pulmonary arterial pressure (PAP) is challenging. Since a small change in PAP (5mmHg) defines pulmonary hypertension (PH), for early detection of PH, a highly sensitive technique is needed. Since PH is progressive in nature, in time, right ventricular failure will cause death. Currently existing diagnostic techniques are limited either by their invasiveness to the body or by their inability to provide a quantitative measure of PAP, even for moderate PH. Further, impairments in oxygen metabolism/delivery mechanisms are also critical in many serious heart conditions. Magnetic resonance imaging (MRI) is being developed around the world as a potential methodology for the assessment of oxygen-related functional changes in the cardiovascular system. However, the scan times associated with commonly employed MRI measurement methods are prohibitively long for some cardiac applications. This dissertation focuses on using MRI to develop noninvasive methods that can provide accurate measurements of pressure and fast measurements of blood oxygen saturations. Both techniques were developed by exploiting the unique ability of MRI to detect changes in field perturbation due to magnetic susceptibility differences in the vicinity of different probing media---a novel pressure-sensitive contrast agent for manometry and deoxygenated red blood cells for oximetry. The first two contributions are theoretical studies aimed at improving the microbubble-based manometry technique. The first of these works explores the parameter space of microbubble-based MR manometry. Based on the conclusions derived, the second work proposes a novel microbubble construct and shows theoretically how such a construct may be useful in improving the sensitivity. The following chapter forms the basis for improving the temporal sensitivity of the oximetry technique. The final chapter concludes with the discussion of future directions on how the magnetic-susceptibility-based functional measures need to be developed further to become clinically useful.
Investigation of epistatic interactions among foraging loci in Drosophila melanogaster

All organisms exhibit a wide array of intricate behavioural phenotypes throughout their lifetime. Understanding the genetic underpinnings of these behaviours will ultimately help to elucidate the cellular and molecular mechanisms that drive these behaviours. In this thesis, I explore genetic contributions to feeding behaviour, using Drosophila melanogaster as a model organism. The foraging gene (for) is a very well known genetic regulator of feeding behaviour in Drosophila melanogaster. While for underlies much of the natural variation in foraging behaviour, I am interested in other genes that may contribute to this complex phenotype. I show that a group of previously isolated mutations influencing larval foraging behaviour also influence food intake in Drosophila. In addition, I demonstrate that many of these functionally related mutations interact with one another in a genetic network to influence foraging behaviour. This thesis employs genetic and behavioural analyses to investigate the pleiotropic nature of complex food-related behaviours.
Environmental testing of CanX-2 and integration of optical systems with the CanX Generic Nanosatellite Bus

This thesis describes the author's twofold work at Space Flight Laboratory. The first half discusses the implementation and the results of the Long Form Functional Testing of the CanX-2 nanosatellite. The LFFT was designed by the author and used for testing and verification of the satellite's functionality both during initial integration and during a rigorous testing regime under expected orbital thermal and vacuum conditions. The second half discusses the development of optical systems for the CanX satellites designed around the Generic Nanosatellite Bus. The first optical system discussed is the BRITE Photometer. Detail is given on the selection process for the imager, the testing procedure for the imager, and the eventual selection of the Kodak KAI-11002 CCD. The second optical system discussed is the design and prototyping of the colour optical camera designed to be flown on all GNB derived missions.
Volume-interleaved SENSE for bilateral breast MRI

Dynamic contrast-enhanced MRI relies on both spatial and temporal resolution in order to distinguish between benign and malignant lesions in the breast. Parallel imaging methods such as Sensitivity Encoding (SENSE) enable speed to be increased while maintaining spatial resolution, but sacrificing signal-to-noise ratio. In this thesis SENSE acceleration was implemented for a dual volume interleaved imaging protocol used to screen high risk patients. This was demonstrated with phantom scans using two dedicated breast coil arrays, and compared to a more commonly used single volume approach in terms of SNR performance. The speed of the dual volume scan was doubled with acceptable losses in image quality and SNR. However, new coil designs are needed for robust noise performance across the entire breast volume.
The development of a modern agricultural enterprise: beef cattle farming in Ontario, 1870-1924

Agriculture dominated Canadian life in late Victorian times, yet we know little about its dynamics. This dissertation describes one aspect of agriculture, beef cattle raising in Ontario, from a broad perspective in order to illustrate how farming enterprises functioned. The work does so by addressing three basic questions. What type of livestock did farmers think was suitable for the production of cattle commodities in relation to economic reality? What was that economic reality? And what shaped that economic reality? Chapter One gives the background to the situation in 1870, and assesses general concerns between 1850 and 1920. Chapter Two describes the purebred cattle industry. Chapter Three looks at the production of the ordinary farmer within the framework of breeder/feeder production systems, animal improvement, and specialization of livestock for beef and dairy purposes. Chapter Four outlines policy regulations by reviewing international quarantine problems, attitudes to bovine tuberculosis, and the development of other regulatory concerns. Chapter Five places Ontario's industry within the nation, the continent, and the international market. Chapter Six explains how the cattle industry related to the meat industry through consumption. chapter Seven reassesses patterns that emerge in earlier chapters and then outlines some international developments in the industry from 1924 to 1996. As early as 1865 beef cattle raising in Ontario was part of an international industry, which had developed by 1875 into a transatlantic system in which Canada and the United States functioned together. Regulation of the modern Canadian beef cattle industry was laid down in response to this pattern. While Canadian beef cattle raising remained centered in Ontario, not in the west, cattle bred on Ontario farms after 1890 reflected the needs of the province's dairying enterprise, not its beef cattle industry. As a result, the quality of beef cattle declined in Ontario. Because of production linkages, the Ontario situation affected how the western arm of the national industry functioned. The rise of Ontario's dairy industry, therefore, was intimately related to the decline of beef cattle everywhere in the nation. Farming for beef in Ontario from 1870 to 1924 was a complex operation with national implications, and international linkages.
Youth at risk in the wilderness

Youth with behavioural problems are sometimes referred to outdoor education programs as part of their mandated rehabilitation. Objective. To compare adverse incident rates between mandated youth and voluntary youth participating in standardized outdoor wilderness education courses. Methods. Retrospective cohort study of youth at a school in Ontario (1996--1998). Individuals were classified as either referred for behavioural problems (mandated), or attending on their own initiative (voluntary) and followed for adverse incidents occurring on course (injuries, illnesses, or behavioural incidents). Results. 623 youth participated in 78 courses. Mandated youth (N = 149) were less numerous than voluntary youth (N = 474). Mandated youth were twice as likely to suffer an incident (OR 2.18, 95%CI 1.47--3.16). Results were confirmed by Kaplan-Meier analyses and remained significant in regression analyses. No deaths occurred. Discussion. Mandated youth were twice as likely to experience an adverse event as voluntary youth, despite both groups being removed from their home environments.
Intentional modeling for enterprise architecture: managing knowledge about "why" to support change

Enterprises often use Enterprise Architecture (EA) as a blueprint to deal with change. Most modeling techniques used in EA are intended for representing the knowledge about data and processes. However, understanding the motivation can be just as important for successful change. Intentional Modeling (IM) can be used to represent the knowledge about "why". This thesis demonstrates a framework showing one way to incorporate IM into EA. Two IM examples, the Business Motivation Model and the i* framework are utilized in this framework to test the feasibility of the incorporation and to assess the potential benefits that IM could bring to EA. Interviews with experts showed that IM can help enterprises make sense of the motivation for change and make informed decisions to deal with change. A health claims payments case was used as a domain example.
Interlocking directorates and corporate governance in Trinidad and Tobago

The is paper examines the occurrence of the interlocking directorate in Trinidad and Tobago from the point of view of corporate governance. In that country the interlocking directorate seems to have been charactersised as a negative feature of publicly listed corporations in Trinidad and Tobago. In this paper however an attempt is made to argue that this is not the case. In fact, when one examines the consequences of interlocks and the impact which those consequences has on the ability of financial investors in corporations to gain a return on their investment together with relevant securities and corporate laws which seek to protect such investors a different picture is painted. The argument made in this paper is therefore that interlocks have been mischaracterized and that in reality they may be an asset to publicly run corporations and their financial investors rather than a burden.

Keywords: Interlocking directorates, Trinidad and Tobago
Corporate governance, Trinidad and Tobago
The influence of nonconscious affect on attitudes and behaviors

We know that consumers are often unaware of the actual stimuli that influence their decisions (e.g., Nisbett Wilson 1977) and there is growing interest in examining the differential impact of implicit and explicit attitudes on behavior (for a recent review see Gawronski Bodenhausen in press). This dissertation investigates the mechanisms and boundary conditions of the influence of implicit attitudes based on nonconscious affect on consumers' attitudes and choice decisions. This research is unique in that participants had access to nonconscious affect and conflicting but relevant product information, a situation which we believe is realistic of what commonly occurs in daily life and provides evidence in support of the idea that there are situations in which nonconscious affect provides the primary basis for attitudes and choice decisions. The second essay investigates the relatively unexplored area of how explicit attitudes emerge from the interaction of product attribute beliefs and nonconscious affect. This essay illustrates that participants do not rely solely on either product attribute information or nonconscious affect but under certain situations follow an additive strategy and incorporate nonconscious affect into their explicitly reported attitudes. We also report evidence of both a direct and indirect effect of nonconscious affect on explicit attitudes. For instance, when nonconscious affect is accessible during exposure to product attribute information, it not only influences participants' liking for a brand, but also shapes how participants construe the product category. The dissertation also includes a discussion of alternative theoretical perspectives on the sources of implicit attitudes and their relationship with explicitly formed attitudes. This dissertation consists of two essays which establish that nonconscious affect plays an important role in consumer decisions. The nonconscious affect was created by conditioning two hypothetical brands with either positive or negative stimuli in which participants were unaware of the contingencies. The first essay demonstrates that if consumers do not form an explicit attitude based on product attribute information, they will rely on an implicit conditioned attitude when making a brand choice. Furthermore, this effect is a robust phenomenon, and is not dependent on low levels of motivation and opportunity.
Measurement and characterization of fear and avoidance in dental anxiety

Dental anxiety is the most common psychological condition encountered in dental practice. Gaps exist in our understanding of its epidemiology and characteristics due to a lack of consistency in the way studies have defined and measured it. The aim of this research was to develop a more comprehensive understanding of dental anxiety in the general population by investigating the prevalence and correlates of fear and avoidance. Specifically, the relationship between these cognitive and behavioural dimensions of dental anxiety was the focus of examination. A new test, the Dental Fear and Avoidance Scale (DFAS), was developed and its reliability and validity tested. Test-retest reliability of the DFAS showed an intraclass correlation of 0.87 for both fear and avoidance dimensions of the scale, demonstrating high reliability suitable for research purposes. The validity of the DFAS was tested by comparing fear and avoidance scores on the DFAS with responses to fear- and avoidance-related questions in a self-report questionnaire. Significant differences (p le; 0.01) were noted between: mean scores for low and high DFAS fear categories and Dental Anxiety Scale (DAS) scores, and questions regarding dental treatment, having a needle in the mouth, and various evoking stimuli; and between low and high avoidance DFAS categories and questions about avoidance behaviours, the frequency of dental visits and when subjects last saw a dentist. A correlation of 0.60 confirmed fear and avoidance as related but distinct entities. The DFAS categorized subjects (n=1184) as 62.7% low fear/low avoidance, 14.4% high fear/low avoidance, 6.3% low fear/high avoidance, and 16.6% high fear/high avoidance. Significant differences (p