VictorJuiz/thesis huggingface dataset:
Development of ion plated aluminide diffusion coatings for thermal cyclic oxidation and hot corrosion protection of a nickel based superalloy and a stainless steel

This project was carried out at the University of Toronto and Cametoid Ltd of Whitby, Ontario. Ohno continuous casting; a novel net shape casting technique, was used to generate, Al-Y, Al-Ce, Al-La, and Al-Si-Y, in form of 1.6 to 1.7 mm diameter alloy wires. These alloy wires exhibited suitable properties for use as feed materials to an Ion Vapor Deposition facility. The deposition parameters were optimized to provide coatings with a compact and cohesive columnar structure with reduced porosity and diffusion barriers that were essential to ensure the success of the diffusion process in the subsequent stage. Solid-state diffusion heat treatment processes were developed in order to form the stable aluminide phases, AlNi and FeAl, on IN738 and S310 substrates, respectively. Experiments simulating the coating service conditions and environments encountered during the prospective aerospace and fuel cell applications were conducted to evaluate the performance of each aluminide coating developed during this study. Thermal cyclic oxidation and molten sulfate corrosion studies were performed on coated IN738 pins at 1050°C and 900°C, respectively, simulating the service environment of turbine engine blades and other hot section components. Molten carbonate corrosion behavior was investigated for coated S310 coupons that were immersed in, or covered with a thin film of molten carbonate, at 650°C, in air plus 30%CO2, to simulate the operating conditions of the cathode-side separator plates of molten carbonate fuel cells. The behavior of the reactive elements, yttrium, cerium, lanthanum, and silicon in enhancing the adhesion of the protective aluminum oxide scale was determined by weight variation experiments, structural examination and compositional analysis. The influence of the base material elements, nickel, chromium, and iron, on the formation of protective oxides was investigated. All coatings were found to provide significant improvement for thermal cyclic oxidation and hot corrosion protection. For protection of IN738, Al-La coatings provided the greatest protection during oxidative thermal cycling, whereas Al-Ce coatings were found to be the most effective for protection against corrosive molten sulfate environments in aerospace applications. For protection of S310 against the corrosive environments of molten carbonate fuel cells, the effectiveness of the aluminide coatings were in the sequence, from the most to the least effective, Al-La, Al-Ce, Al-Y, and Al-Si-Y Mechanisms for Lanthanum and cerium protective behavior in high temperature aluminide diffusion coatings were suggested from the results of this study combined with literature information.
The problem of pace: The drive towards a global intellectual property regime

A commanding movement is underway driven by interest groups in developed countries to re-regulate the global environment with ever-increasing levels of intellectual property protection. The movement's sheer pace not only has repercussions on developing countries and their ability to compete but also may negatively affect innovation in the developed world. The literature suggests strategies available to developing countries to work within the shifting IP environment, but these strategies do not replace the primary importance of developing countries simply continuing to resist the aggressive global IP agenda as best they can. Given there is some consensus that time is needed, it follows that in order to buy that time, generating workable solutions to the collective action problem that faces developing countries, needs to be top priority. Small and mid-sized firms in the developed world have certain aligned interests with developing countries and should consider becoming strategic allies in the fight.

Keywords: Intellectual property, Developing countries
Randomly ranked mini slots: a fair MAC layer protocol for ad hoc networks

Reliable medium access in ad hoc networks is necessary for the development of this promising technology. However, the Medium Access Control layer in a distributed network is difficult to manage. The shared channel and limited information available at each node make collisions and unfairness common place and must be dealt with. In this thesis we propose a MAC layer protocol that achieves excellent throughput and fairness results. Our protocol has two versions. Randomly Ranked Mini Slots with Busy Tones (RRMS-BT), is the better performer of the two and requires busy tones. Randomly Ranked Mini Slots (RRMS) does not use busy tones and is compatible with 802.11. Our protocol achieves excellent results by utilizing features such as mini slots and pseudo random ranks. A detailed comparison and extensive simulations of our protocol to other proposed protocols that have been shown to excel in throughput and/or fairness are also included.
Soluble VEGFR-2 as a surrogate biomarker for tumor angiogenesis and anti-angiogenic therapy

Unrestricted tumor growth requires blood vessel development, a process called tumor angiogenesis, and therapeutic inhibition of this process is now a validated anti-cancer treatment strategy. This thesis introduces a novel soluble form of the vascular endothelial growth factor receptor 2 (sVEGFR-2) and outlines studies designed to assess the potential exploitation of this protein as a surrogate biomarker of tumor angiogenesis and anti-angiogenic drug activity/efficacy---particularly for those drugs that target the vascular endothelial growth factor (VEGF) system.sVEGFR-2 is a sim;160 kDa soluble protein that can be detected in both mouse and human plasma, as described in Chapter 2. The sVEGFR-2 was found in conditioned media of mouse and human endothelial cells, thus suggesting that it may be secreted or proteolytically cleaved from the cell, and potential biological activity was inferred from experiments in which mouse sVEGFR-2 could bind to VEGF-coated plates, implying possible endogenous functionality in VEGF signaling. Pre-clinical studies were subsequently undertaken evaluating the relationship between sVEGFR-2 and tumor burden as well as an assessment of underlying factors governing in vivo protein level modulation, as described in Chapter 3. Various mouse cancer models uncovered an inverse relationship between the levels of sVEGFR-2 and tumor burden and further experiments demonstrated that plasma sVEGFR-2 decreases are mediated largely by tumor-derived VEGF down-regulation of VEGFR-2 receptor expression. The role of sVEGFR-2, as well as other circulating proteins, as surrogate biomarkers for anti-angiogenic inhibitors was evaluated, and my results demonstrated that clinically observed molecular changes can be recapitulated in drug-treated tumor-free mice in a dose-dependent manner which plateau after 4 days of consecutive treatment, reverse following discontinuation of therapy, and correlate with anti-tumor activity. Taken together, this work introduces a new and potentially important component of angiogenesis and pre-clinically examines sVEGFR-2 for its potential utility to be clinically exploited as a surrogate biomarker of both VEGF-dependent tumor growth as well as a tumor-independent measure of anti-angiogenic drug activity---possibly aiding in defining optimal biologic dose range for such drugs and in interpreting emerging clinical findings related to this protein.
A genome-wide screen in Saccharomyces cerevisiae to identify novel genes that interact with telomerase

Replication of linear chromosomes is non-conservative. Synthesis of the lagging strand requires an initiating primer that must be removed at the chromosome end, thereby preventing replication to the terminus. This results in shortening of chromosomes with successive cell divisions. To prevent the loss of essential genes with cell division most eukaryotes have specialized repetitive, non-coding DNA (telomere) and a means to replenish this DNA (telomerase). Budding yeast is a highly tractable model organism, allowing the discovery of many genes affecting telomere length. This study utilized the yeast deletion collection to identify twenty genes that interact genetically with the catalytic subunit of telomerase. Telomere length control is inappropriately regulated in human tumour cells and a high degree of homology is seen between human and yeast cells with respect to telomere homeostasis. Elucidating the exact role of these genes, could allow for a better understanding of this essential process in humans.
Signaling mechanisms of parathyroid hormone regulation of insulin-like growth factor binding protein-5 in osteoblasts

Parathyroid hormone (PTH) is an essential regulator of extracellular calcium homeostasis. PTH is secreted from the parathyroid glands in response to low plasma calcium concentrations and restores levels to normal by stimulating calcium reabsorption in the kidney and increasing bone resorption to release mineralized calcium. In addition to its catabolic effects in bone, PTH is capable of stimulating bone deposition when administered intermittently. This thesis examined the signal transduction systems involved in PTH-regulation of an osteoblast marker of bone anabolic activity, insulin-like growth factor binding protein-5 (IGFBP-5).I determined that the transcription factor Sp1 bound in a PTH-dependent manner to the IGFBP-5-GC-element and a Sp-1 consensus oligonucleotide. Additionally, overexpression of Sp1 increased PTH-stimulated IGFBP-5 transcript levels. Sp1 was dephosphorylated following PTH treatment and the protein phosphatase inhibitor okadaic acid blocked the dephosphorylation of Sp1 by PTH and partially abrogated the PTH-induction of IGFBP-5 transcript levels. IGFBP-5 potentiates the anabolic actions of insulin-like growth factor-I in bone and PTH increases the expression of IGFBP-5 in osteoblasts. Using an osteoblastic cell-line, UMR106-01, I identified the signal transduction intermediates that mediate PTH induction of IGFBP-5 transcript levels. I confirmed an essential role of protein kinase A (PKA) and also demonstrated that the PKC pathway was required by using a non-selective PKC inhibitor. Using subcellular fractionation I identified PTH stimulation of PKC-delta nuclear translocation and a dominant negative mutant and selective inhibitor of PKC-delta, both inhibited the PTH-induction of IGFBP-5. In summary, my studies demonstrated that PTH increased IGFBP-5 gene transcription in osteoblasts by activating PKA and PKCdelta. These pathways in turn increased the activity of a protein phosphatase to dephosphorylate and thus activate Sp1 binding to a GC-rich element in the IGFBP-5 promoter. These studies have identified novel cellular targets of PTH signal transduction and may facilitate the development of improved therapeutic strategies for the treatment for osteoporosis. PTH stimulation had no effect on the half-life of the IGFBP-5 transcript based on mRNA stability experiments. A reporter gene assay using approximately 1000 base pairs of the IGFBP-5 5'flanking region indicated that PTH induced IGFBP-5 gene transcription. Deletion and mutation analysis identified a GC-rich element in the proximal promoter region of the IGFBP-5 gene that mediated approximately 50% of the PTH-induced increase in transcription.
The pharmacological signature of GABAAampus

Two forms of GABAergic inhibition exist in the brain: a persistent tonic and transient synaptic inhibition. Mammalian GABAA receptors are hetero-pentameric, ligand-gated, chloride channels assembled from a family of ge;19 related subunits. To test the hypothesis that tonic current in CA1 hippocampal pyramidal neurons is mediated by alpha5 subunit-containing GABA A receptors, we used an assortment of subunit-selective drugs. Previously, we showed that classical benzodiazepines enhance the tonic current. Here, we show that tonic conductance is modulated by the alpha5-selective negative modulator L-655,708 but not by the alpha5-sparing imidazopyridine, zolpidem. Moreover, beta2/3-selective positive allosteric modulators enhance the tonic current where delta-sensitive neurosteroids do not, suggesting that the alpha5 subunit assembles with beta2/3 and gamma subunits to form tonic GABA A receptor complexes in the hippocampus. Deletion of the alpha5 subunit results in a 75% reduction in tonic current. Thus, we attribute tonic inhibition in hippocampal pyramidal neurons to alpha5-containing GABA A receptors.
Methods of enhancing mechanical properties of hydrogel tubes used as nerve guidance channels in rat spinal cord injury

Crosslinked, porous poly(2-hydroxyethyl methacrylate- co-methyl methacrylate) (PHEMA-MMA) tubes used as conduits in transected rat spinal cord, were prepared in cylindrical glass molds by using a new centrifugal casting process developed in our group. It has been shown previously that silane-modified glass molds influence morphology and elastic modulus of hydrogel tubes. We have investigated the effect of mold surface modification on hydrogel tube properties, by treating glass with three alkoxysilanes having either ethoxy, amine, or fluorocarbon end groups. Results have shown that ethoxy and amine-containing silanes had the greatest impact on creating hydrogel tubes with a continuous, biphasic wall structure, and enhanced elastic modulus. In a second approach to improve hydrogel tube mechanical strength, we have proposed that by employing helically wound plastic fibers embedded in the hydrogel tube wall, the transverse compressive strength of tubes will be significantly increased. After successfully synthesizing, and mechanically testing poly(caprolactone) fiber-reinforced hydrogel tubes in compression mode, results have confirmed our hypothesis.
General education within Ontario's community colleges: second class citizens?

General education occupies a unique position within the college system, in that the colleges are primarily concerned with the teaching of vocational skills, while General Education courses tend to be Liberal Arts-oriented. For this reason, many within the college community question the relevance of general education. Through a series of qualitative interviews, the researcher seeks to understand the relevance of these perceptions to the identity of the general education faculty. A thematic analysis utilizing symbolic interactionist theory reveals that general education faculty tend to identify with each other in their vision of general education. The faculty also tend to form strong identities with regards to the value of teaching and social activism. The researcher seeks to place these patterns into a materialist context, by exploring the relevance of budgetary restraint, full-time vs. non full-time status, and power. In conclusion, the researcher explores potential areas for future research in this area.

Keywords: General education, Ontario
Community colleges, Ontario
Community colleges, Faculty
Community colleges, Ontario
Symbolic interactionism
Dynamic modeling and analysis of vehicle's smart front-end structure for frontal collision improvement

In this research, two types of smart front-end structure are proposed to improve vehicle crashworthiness. The first type consists of two non-extendable hydraulic cylinders parallel to the longitudinal members. The second type consists of two extendable hydraulic cylinders integrated with the front-end structure. The literature review shows that little has been done for the development of simplified models for automotive crash problems in general, and smart front-end structures in particular. The development of such models is desirable for use in the initial concept design stage of automotive structures. The work carried out in this research includes developing and analyzing mathematical models of vehicle-to-vehicle and vehicle-to-barrier in different frontal collision events. In these models, vehicle components are modeled by lumped masses and nonlinear springs. Moreover, the hydraulic cylinders are represented by nonlinear dampers elements. Two types of nonlinearity forms, piecewise and cubic, are used to define the characteristics of both nonlinear springs and dampers. In this research, the dynamic responses of the crash events are obtained with the aid of analytical and numerical approaches. Moreover, the intrusion injury and occupant deceleration are used for interpreting the results. It is demonstrated from simulation results that significant improvements to both intrusion and deceleration injuries are obtained using the smart front-end structures. Furthermore, the vehicle compatibility and the crash severity have been significantly minimized.
The perspectives and responses of children on the physical and social environments of a camp for children with cancer

Approximately 1,285 Canadian children (aged 0-19 years) are diagnosed with cancer annually (National Cancer Institute of Canada, 2006). There has been little investigation about children's views on non-traditional places of care provision. An exploratory, retrospective, qualitative design was used to elicit children's perspectives on and responses to a specialized summer camp and their suggestions for change. Gesler's (1991, 1992) notion of therapeutic landscape (TL) was used to conceptualize the physical and social environments of the camp. Children with cancer who were 6-16 years of age, spoke English or French, and lived in Ontario were eligible to participate in the study. Children who had severe neurological and/or sensory impairments, were receiving palliative care, or had participated in counselor-in-training or adolescent programs were excluded. Data were collected during individual, semi-structured interviews using photograph elicitation techniques with 35 children within 7 days following a for 2-week session at camp. The data were analyzed based on a coding scheme consistent with the TL framework. In summary, children perceived a network of adults and other campers watching over them. In various contexts, they accommodated to or resisted this surveillance. These findings suggest ways to enhance the delivery of health care to children in non-traditional places of care. The overarching theme that reflected children's general perspectives on camp was Watching Over Me. This theme included two sub themes: (a) Feeling Cared For and (b) Feeling Cared About. Data categorized in the first sub theme focused on regimens of care and included children's descriptions of being kept safe and receiving treatment. Data categorized in the second sub theme focused on children's accounts of actions that compensated for regimented care and included supportive care and playful care. Children's responses to feeling watched over were categorized as accommodative and resistant behaviours. Children's suggestions for change focused on providing more choices, space, and supportive places.
Process development for the production of protein isolates from Estonian rapeseed

To reduce the dark color of precipitated protein isolate, the protein solution was treated with 0.05% hydrogen peroxide during precipitation. However, even though hydrogen peroxide improved the color of the isolate, it altered the protein functionality and reduced the protein content of soluble protein isolate. Therefore, another method for improving the color of precipitated rapeseed protein isolate must be developed. The observed low quality of the precipitated protein isolate was caused by the oil in the product. Thus, defatted rapeseed meal must be used as the starting material for commercial production of high-quality rapeseed protein isolates. This Master's thesis was part of a process development for obtaining protein isolates from Estonian rapeseed. Precipitated protein isolate and soluble protein isolate were the ultimate products of this process. The starting material was industrially pre-pressed rapeseed meal with 36--38.5% protein and 9--12% oil. This has been the first project to extract protein from a rapeseed meal that contains oil. It was extracted with aqueous alkali at pH 12 and at room temperature for 30 minutes. In an average experiment, around 36--42% of protein was soluble, less at the last part of the project when bleached precipitated protein was produced. The protein extract was concentrated by ultrafiltration by a factor of five and purified by diafiltration with five diavolumes of water prior to isoelectric precipitation at pH 5. The protein remaining in solution was further concentrated by ultrafiltration and diafiltered to remove excess salt from the solution. The precipitated protein isolate contained 74% (Nx6.25) protein and 15% oil, the soluble protein isolate was oil-free and contained 46--60% protein. Hydrogen peroxide reduced the protein content in soluble protein isolate. About 23--25% of the original protein is recovered as usable food product.
Systemic interactions in breastfeeding families

The aim of this study was to investigate and describe systemic interactions in nursing families. The participants in this study were families who engaged in physiologically based nursing patterns and key informants who were familiar with similar families. Actively nursing families were observed in their natural home environments during at least three home visits, and one family was observed over a four-year period. Interviews with and observations of the families were recorded via audio and videotape. Data were transcribed and organized into case studies. The second group of key informants consisted of members of present and former nursing families, and lay and professional counsellors who provided descriptions of nursing families. Data from this group were gathered through phone and personal interviews that were recorded, transcribed and organized into categories for review. The findings from both groups of participants were compiled, providing insight into family interaction associated with nursing. The interactions in the families that were studied were influenced by each family's unique style and evolving family themes and patterns associated with nursing that reverberated throughout the system. Themes of reverence for physiological processes, perspectives of nursing as normal and encompassing, and respect for and sensitivity to children's needs and individual rhythms were associated with the development of nursing relationships based on child-initiated cues. Parents' attuned responses to children's cues for nursing and proximity evolved into an overall sensitive parenting style extending beyond nursing and early childhood. Children mirrored the sensitivity that they experienced in their relationships, contributing to an overall sensitive family style. The circulation of themes and patterns associated with the development of sensitivity through nursing was influenced by complementary parenting task allocation, open communication patterns and tutoring. Unresolved couple discord and closed communication interfered with these processes and was expressed through distancing behaviours, the use of artificial pacifiers, and naming nursing as feeding. This study concluded that interactions in the nursing sub-system affect and are influenced by overall systemic interchanges, and seem to facilitate the development of a sensitive family style. (PsycINFO Database Record (c) 2016 APA, all rights reserved)