VictorJuiz/thesis huggingface dataset:
Application of PIV technique for the investigation of flow features within metallurgical vessels

A non-intrusive flow visualization technique, using particle image velocimetry (PIV) was developed to concurrently measure instantaneous velocity data for entire planes of flow within a water model. The apparatus constructed proved capable of measuring flow planes in variable orientations. This technique has proven suitable for measurements in shallow bath flows such as the bottom gas stirred Electric Arc Furnace (EAF). Three models were constructed for technique development and analysis, including one simplified bottom stirred EAF case. The data measured has been used to map both time average flow patterns and velocity distributions for different experimental conditions. Vorticity and mean square velocity fluctuations were calculated and plotted to determine the distribution of turbulent flow activity. The existing flow similarity theory was determined insufficient for the scaling of bottom stirred EAF parameters. The model and prototype systems operate within the same regimes allowing for qualitative comparisons of results.
Effect of carbohydrate source on postprandial blood glucose in subjects with type 1 diabetes using insulin lispro

Treatment of type 1 diabetes (T1D) with lispro insulin reduces postprandial hyperglycemia, but because of its rapid onset of action, postprandial hypoglycemia may occur. To see if glycemic index (GI) and proportion of carbohydrate absorbed as glucose (Pg) affected glycemic responses and occurrence of hypoglycemia, 8 T1D subjects on lispro were studied for 4 h on 5 days after overnight fasts. Subjects took their usual insulin dose and ate 50g carbohydrate from a starchy food (Pg = 1; instant potato GI = 83, white bread GI = 71, spaghetti GI = 41, barley GI = 25) or pineapple juice (Pg = 0.5; GI = 46). Glycemic responses differed significantly for the different foods and were closely related to GI (r = 0.98, p < 0.01). Hypoglycemia was more frequent (p < 0.05) for foods with low Pg, while time to hypoglycemia was shorter with lower GI. In conclusion, GI predicts glycemic responses of foods in T1D subjects using lispro. Pg affects the occurrence of hypoglycemia while GI affects its timing.
Activation of Neutrophil Collagenase in Periodontitis

Neutrophil collagenase (MMP-8) is an important mediator of tissue destruction in periodontitis and has been suggested as a possible diagnostic indicator of progressive lesions. However there is wide inter-subject variation in the specific activity of different forms of the enzyme which complicates diagnostic utility. I have studied the relationship between enzyme activation and the generation of different molecular mass forms of MMP-8 in gingival crevicular fluid (GCF) samples of patients with periodontitis and of healthy controls. MMP-8 from purified peripheral blood neutrophils was used as an internal control and to optimise stability and testing conditions. The specific activity of MMP-8 was determined by a soluble biotinylated collagen degradation assay (SBA); the MMP-8 fragments were analysed by Western blots (WB). On replicated analysis, both assays were reproducible (SBA r = 0.96; WB r = 0.98) and sensitive. I conclude that gingival crevicular fluid contains a 60 kD MMP-8 with wide inter-patient variation of activity, and that some of the 60 kD species may correspond to super-activated MMP-8. (Abstract shortened by UMI.)
The costs and consequences of using bisphosphonates as prophylaxis against the sequelae of bone metastases secondary to breast cancer

'Purpose'. The costs and consequences of prophylaxis with oral clodronate and intravenous pamidronate in bone metastases of breast cancer were determined from a modified Ontario Ministry of Health perspective. 'Methods'. An incidence based, from diagnosis of bone metastases to death, chart review study. Results were presented as crude mean costs and average lifetime costs (including terminal care) per patient. Future costs were discounted at 3% and 5%. 'Results'. The crude mean and average lifetime costs were $47,857 (n = 59) and $60,992 (1999 CDN $), respectively. The difference in costs between oral clodronate (n = 34) and intravenous pamidronate (n = 18) groups was not significant (p = 0.64), and remained robust after a probabilistic sensitivity analysis. Inpatient and terminal care were the major cost drivers, comprising 45% and 25% of overall costs. 'Conclusions'. The costs of management of patients who began oral clodronate and intravenous pamidronate prophylactic therapy were not significantly different.
Semantic transparency of English words and Grade Five French Immersion students

This study examined French Immersion students' use of their knowledge of French when reading in English. Past research suggested that explicit metalinguistic instruction might be necessary for Early French Immersion (EFI) students to benefit from English and French cognates. 24 Grade Five French Immersion students participated in this study. The students completed a French Word Knowledge Task and an English Short Answer Instrument (SAI). Three Metalinguistic Lessons were taught during the 4-week study. A random sample of students participated in two Bilingual Strategy Interviews. The qualitative results showed a significant increase between pre and post SAI total score, indicating that students benefited overall from the metalinguistic lessons. During the Bilingual Strategy Interviews, students were able to describe the ways they used their metalinguistic strategies to improve comprehension, including recognizing cognates, translating and transferring in both languages. This research study demonstrated that heightening students' awareness of the potential for cross-lingual transfer helped these EFI students gain more meaning from cognate words.
Characterization of Ras-GRF2, a bifunctional guanine nucleotide exchange factor for the Ras and Rac GTPases

Activation of Ras is catalyzed by guanine nucleotide exchange factors, including Ras-GRF2, which was cloned in our laboratory. Ras-GRF2 is a widely expressed protein comprised of a number of modular domains. They include two pleckstrin homology (PH) domains, a coiled-coil motif, an ilimaquinone (IQ) motif, a Dbl-homology (DH) domain and a Cdc25 domain. Here I report the characterization of the IQ motif, the DH domain and the Cdc25 domain, and demonstrate that Ras-GRF2 functions as a calcium-responsive dual-specificity exchange factor for the Ras and Rac GTPases. A recombinant glutathione S-transferase fusion protein containing the Cdc25 domain of Ras-GRF2 stimulated net nucleotide exchange on Ras, ' in vitro'. Consistent with this result, Ras-GRF2 was also able to activate the extracellular signal-regulated kinase (ERK), which functions downstream of Ras. ERK activation was found to be both Ras-dependent and calcium-responsive. The coimmunoprecipitation of Ras-GRF2 and the calcium sensor calmodulin was shown to be dependent on the presence of an intact IQ motif. The calcium-responsive nature of Ras-GRF2 activity may be related to its subcellular localization. In unstimulated cells, transiently expressed Ras-GRF2 proteins appeared cytosolic, whereas in cells stimulated with a calcium ionophore, a relocalization of Ras-GRF2 to the cell periphery was observed. Although the overexpression of Ras-GRF2 in NIH 3T3 and Rat2 cells was not transforming, the stable expression of Ras-GRF2 in 293 epithelial cells altered the growth properties of the cells. GST pulldown experiments revealed that Ras-GRF2 associated with the nucleotide-free forms of Ras and Rac, weakly with Rho, and not at all with Cdc42. The interaction between Ras and Ras-GRF2 required the Cdc25 domain, whereas its association with Rac was mediated by the DH domain. Ras GRF2 was shown to catalyze nucleotide exchange on Rac. Ras-GRF2 also activated the stress activated protein kinase (SAPK) in a calcium-dependent manner. SAPK activation required the IQ and DH domains, and to a lesser extent, the Cdc25 domain. The activation of both ERK and SAPK by Ras-GRF2 could be inhibited by the dominant-negative mutants of Ras or Rac. Full activation of SAPK by Ras-GRF2 appears to involve the activation of Ras by the Cdc25 domain, as expression of the Cdc25 domain led to SAPK activation while a point mutant of Ras-GRF2 that can no longer bind to Ras activates SAPK less effectively than wild-type. The PH domains of Ras-GRF2 do not appear to be involved in SAPK activation. Instead, expression of the DH domain or the amino terminal PH domain-deleted mutant resulted in higher levels of SAPK phosphorylation than that observed with wild-type Ras-GRF2.
Chemical equilibrium analysis of combustion products at constant volume

A computational code is developed to determine the high-temperature and high-pressure combustion products of energetic materials inside a closed, constant-volume, adiabatic vessel assuming chemical equilibrium occurs. The product mixture is modelled as a mixture of gases with pure condensates dispersed uniformly. To solve this problem, the Villars-Cruise-Smith (VCS) minimization algorithm is applied. This algorithm is based on a stoichiometric formulation using chemical equations and is optimized to avoid matrix inversions during iterations. Procedures are also implemented for treating trace gaseous species and the special situation of phase transitions of condensed substances. The resulting Extended-VCS (E-VCS) code is flexible, robust and easy to use. Different models and complicated equations of state can be used for describing the mixture of gases and the products, and systems with several hundred species can be handled. The solution algorithm and procedures of the E VCS code are compared with those of three previous major codes for the same analysis, the Bagheera, Blake and NASA-Lewis codes, using a range of test problems. The E-VCS code straightforwardly solves problems with many condensed products, including near gasless conditions and phase transitions--problems the previous major codes have difficulty solving.
Reduced surface-wave twin arc-slot antennas on electrically thick dielectric substrates

In this work, a novel planar twin arc-slot antenna design is introduced which excites very little surface-wave power. The twin arc-slot antenna consists of two concentric, second resonant arc-slots of equal radius printed on an electrically thick dielectric substrate. For a specified substrate, arc-slot length and frequency it is demonstrated that there is a critical arc-slot radius at which the power lost to the dominant TM0 surface-wave mode is minimized (through phase cancellation) and the radiation efficiency is maximized. A theoretical radiation efficiency of 90.535% is obtained for a twin arc-slot antenna at second resonance on a quarter dielectric wavelength thick substrate with a dielectric constant of [epsilon]'r' = 10.2 at a design frequency of 9.239 GHz. The theoretical surface-wave efficiency is 99.840% indicating that surface-wave suppression is almost complete and almost all of the reduction in radiation efficiency is attributed to back-side radiation loss. For a simple two-port feed network, simulated and experimental radiation pattern data are shown to be in agreement with theory. Experimental radiation patterns display little sign of interference from Spurious radiation of surface waves from the edges of the finite substrate over a frequency bandwidth of approximately 3.5%. An experimental -10dB input impedance match bandwidth of approximately 2 GHz is also observed.
A return to the garden, re-interpreting personal stories : a hermeneutic narrative inquiry into my experience of learning

Significant personal learning often comes through the hermeneutic re-construction of narrative. Unfortunately, we have few accounts of this complex process as it unfolds and that is what this study provides. This study is a demonstration thesis. This hermeneutic narrative inquiry highlights an aspect of narrative inquiry. It focuses our attention on that aspect of narrative inquiry that Connelly and Clandinin refer to as restorying. My thesis question is "What happens when we restory the narrative?" In this inquiry I emphasize the experience of hermeneutically returning to the story. In each hermeneutic return to the story I elaborate and interpret the original story. In this way I demonstrate the nuance of my learning experience. I apply the educational theory and practice of Connelly and Clandinin, who understand teachers as curriculum makers (Connelly and Clandinin, 1988; Elbaz, 1983) to my experience as a learner. I take Connelly and Clandinin's idea deeper into a hermeneutic context (Gadamer, 1994). I discovered and demonstrate how image making plays a major role in my narrative constructions and learning experience as aesthetic experience. I discovered that as I re-interpreted personal stories, shared them, and re-interpreted them again, learning occurred as a constant unending process of narrating my experience. I found the goal, what some call 'narrative unity', seemed to enhance my 'personal learning narrative'. I shared these findings with a doctor of chemistry. The concept of ' learning recovery rate' as a way of thinking about my narrative experience as learning experience emerged. I define 'personal narrative recovery rate' as my ability to learn; it depends on my ability to revisit and recover stories in the past and then return to the present. The speed with which I can do so reflects my ability to transform my stories and my life. This, in essence, is what I consider an example of my 'personal narrative learning' and personal 'narrative recovery rate'. This hermeneutic narrative inquiry into how I learn, demonstrates the potential for developing a theory of learning based on image making and re-interpreting personal stories through hermeneutic narrative inquiry.
Generation and the individual in Descartes, Malebranche and Leibniz

This dissertation is an examination of the emergence of the preformation doctrine of generation in three early modern philosophers: Descartes, Malebranche and Leibniz. Received wisdom on this question maintains that the preformation doctrine became so popular in the seventeenth century because it seemed most capable of explaining generation of living beings within the limits of the reigning mechanical philosophy. This dissertation considers another motivation, generally neglected by commentators, for the rise of this doctrine in the early modern period--namely to account for the individuation, unity and enduring identity of material bodies. With the clear exception of Leibniz, early modern rationalists rarely developed robust theories of material individuation, but I argue that the living, organic being is a paradigm example of the enduring material unity for all three philosophers under examination. Descartes' theory of generation, however, is unable to account for the unity of this living being, although it is able to account for species-specific complexity even given the nascent mechanism that he embraced. So Malebranche introduces preformation as a way to remedy this failure. Nonetheless, both Descartes' and Malebranche's forms of mechanism threaten the material unity of organisms on a number of fronts. Leibniz's starting point, I argue, is the problem of individuation very broadly conceived, and his solutions to the various aspects of this problem all dovetail to culminate in his quite unique theory of preformation and in a notably different version of mechanism than that held by his predecessors. All three thinkers draw on Aristotelian ideas about substantial unity and organic beings, though they do so in different ways. I thus show that the usual story (much challenged in recent decades) of the early moderns' radical break from Aristotelianism crumbles under a consideration of the individuation of living individuals. I also argue that teleology enters into all three philosophers' work more than normally supposed. Finally, I use my findings to suggest new ways of looking at central metaphysical questions of the seventeenth century (Malebranche's theory of causation is paramount here) and new ways of reading the historiography of generation in the early modern period.
Volumetric estimation of breast density for breast cancer risk prediction

Mammographic density has been shown to be a strong risk predictor for breast cancer. Compared to an assessment by radiologists, computer-aided analysis of digitized mammograms provides a quantitative and more reproducible method for measuring amount of density in the 2D projection of the breast. This thesis improves on existing computer-aided methods, by developing a tool for breast cancer risk assessment, which considers the whole 3D volume of the breast, instead of 2D projected area. The volumetric breast density (VBD) estimation requires an initial inhomogeneity correction which reduces variations in the image of a uniform object from 15% to <2%. Then, VBD is estimated to within 2% of the actual value, using information about an aluminum wedge (imaged along-side the breast), breast thickness and imaging technique. VBD can be used for determination of the appropriate frequency of breast cancer screening, and might prove useful in predicting the effect of intervention measures such as drug therapy or dietary change.
Hardware emulation and real-time simulation strategies for the concurrent development of microsatellite hardware and software

In small satellite projects on short schedules, there is often insufficient time to develop new hardware and subsequently write software once the hardware is tested and ready. However, emulating the hardware may be useful if the effort involved in doing so is kept to a minimum. The purpose of the emulation should be to act as a substitute for the missing hardware so that flight code can be developed concurrently with the hardware. The use of the real-time development system RT-Lab&trade; provides a flexible environment to develop flight software early in the development cycle of a small satellite. The degree to which hardware can be emulated is investigated using the development of the attitude control system for the MOST microsatellite as an example. A trade study is presented that indicates when the cost of programming the emulator outweighs the benefits. A level of hardware emulation is recommended that facilitates the early development of flight code.
Teens educating and confronting homophobia, space, anti-oppression education and identity

The thesis is a study of the Toronto-based Teens Educating Against and Confronting Homophobia (TEACH), a peer-based youth program focused on addressing issues of homophobia. The study examines the ways in which participation in TEACH permits youth to actively challenge homophobia, and how the space of the project nurtures a critical analysis of the construction of identity. The study demonstrates some of the ways in which a peer-based model generates personal narratives and challenges diverse discourses within an anti-oppression framework. It shows how youth have taken up their identities as gay, lesbian or bisexual youth in spaces of the school, the mainstream gay, lesbian and bisexual community, and TEACH itself. The research suggests the need for a combination of trust and reliability, supportive adult facilitation, and reliable structures that support youth in exploring complex issues. It also suggests a possible connection between adolescent development and the acquisition and use of varying theoretical constructs.
A modelling and vibration analysis of spinning disks

This thesis considers a modelling and vibration analysis of thin spinning disks. Both in-plane and transverse vibrations are considered. Kirchhoff and von Karman theory of plates along with Hamilton's principle are used to derive linear and nonlinear equations of motion for the vibrations of a spinning plate. In-plane and rotary inertias are naturally accounted for in this procedure. The resulting equations are similar to those previously derived in the literature but contain some additional terms. These linear and nonlinear equations are subsequently analyzed. New orthogonality properties of the in-plane modes are derived and are used to construct solutions to the linear, forced in-plane vibration problem. The linear transverse vibration equations are derived with new terms. These new terms are explained physically and their effect on the frequencies of vibrations is analyzed. Nonlinearly coupled transverse and in-plane vibrations are considered while including the effect of in-plane inertia which has always been neglected by other researchers. It is found that the inclusion of in-plane inertia introduces the possibility of internal resonance between the in-plane and transverse modes of vibration.
A fully-coupled algorithm for aerodynamic design optimization

A fully-coupled algorithm is presented to solve aerodynamic design optimization problems. The discretized flow, adjoint, and optimality condition equations are solved as a single system of nonlinear equations using an inexact Newton method with linesearching. Quasi-1D, inverse, nozzle design and inviscid, 2D, inverse, airfoil shape design cases are solved, however the method is applicable to more general design cases. While the system is approximately twice as large as the system describing the flow solution, fewer iterations are required to find the optimum. The most important advantage of this method is that only a single flow solve is needed to perform the optimization, as opposed to the discrete adjoint method which requires several. Many improvements have been made to the algorithm, both in the system formation and solution method. The result is an algorithm that is reliable, robust, accurate, and fast in providing optimum solutions for the cases considered.
Comments on Mallow's C¦p statistics and multicollinearity effects on predictions

Selecting a subset of predictors by considering all possible combinations of variables with corresponding values of Mallows' 'Cp', AIC and BIC is discussed. It is shown that when a model with the smallest ' Cp' is selected 16% of non-related predictors had the chance of being entered in the model. The effect of multicollinearity on the prediction errors is studied. When multicollinearity is not severe the fitted model can be used for prediction. When severe multicollinearity exists it is still safe to interpolate but not to extrapolate.
The nutrient and phytonutrient composition of Ontario-grown beans and their effect on azoxymethane-induced colonic preneoplasia in rats

Beans have long been recognized for their nutritional quality. Epidemiological studies have shown that populations consuming substantial amounts of beans in their daily diets are at low risk of developing many chronic diseases including colon cancer. The first aim of this thesis was to investigate both the nutritional and phytonutrient composition of raw and processed Navy, Kidney and Fava beans. The nutrient and phytonutrient analysis of raw was in good agreement with published literature. The nutrient and phytonutrient content of canned beans, homogenized with the liquid content found in the can, appeared to be slightly higher than those beans that were not homogenized with the liquid contents, suggesting leaching. The second aim was to investigate the effects of canned navy bean consumption on the development of preneoplastic lesions in the colons of azoxymethane-treated F344 Fisher rats. The incidence of aberrant crypt foci (ACF) and aberrant crypts (AC), induced by azoxymethane in rats fed canned navy beans showed significant reductions in the number and size compared to rats consuming a bean-free diet. This study demonstrates that Navy, Kidney and Fava beans contain anticarcinogenic phytonutrient compounds capable of inhibiting chemically-induced preneoplastic lesions in the rat colon.