VictorJuiz/thesis huggingface dataset:
Function of receptor tyrosine kinases in G¦i-deficient cells, preferential suppression of insulin signalling

Heterotrimeric G proteins function as critical links in the signaling pathways of heptahelical receptors, but their role in signaling by receptor tyrosine kinases, such as the insulin receptor is less clear. We have developed stable L6 myocyte lines in which a loss of Gi function can be controlled by tetracycline-regulated expression of a full-length Gi-alpha2 antisense RNA. Antisense clones cultured in the absence of tetracycline exhibit a 50 to 70% reduction in endogenous Gi-alpha protein. Transcriptional readout assays indicate that Gi depletion causes selective inhibitory effects on signalling by both heptahelical receptors and receptor tyrosine kinase receptors. Insulin activation of the cfos serum response element and hexokinaseII is significantly reduced in Gi-antisense myoblasts and myotubes. In contrast to insulin signaling, PDGF-dependent activation of target gene promoters is largely independent of Gi protein levels in our antisense L6 cell model. These experiments illustrate a role for G i in the signaling pathway of specific receptor tyrosine kinases and support a model in which loss of Gi function can contribute to an insulin resistant phenotype.
A numerical investigation of large bubble translation behaviour due to forced vibration under microgravity

Understanding the stability of fluid interfaces subjected to small vibrations under microgravity conditions is important for designing future materials science experiments to be conducted aboard orbiting spacecraft. During the STS-85 mission, experiments investigating the motion of a large bubble resulting from small, controlled vibrations were performed aboard the Space Shuttle Discovery. To better understand the experimental results, a Volume-of-Fluid numerical simulation of the experiment was conducted. The simulation proved capable of accurately predicting the experimentally determined bubble translation behaviour. Linear dependence of the bubble translation amplitude on the container translation amplitude was confirmed. In addition, the simulation model has also been used to confirm predictions of a theoretical inviscid model of bubble motion developed previously. Finally, a "spring-analogy" model is proposed predicting the nature of the transient bubble translation response to sudden changes in vibration characteristics.
Scoped behaviour for optimized distributed data sharing

We introduce the novel 'scoped behaviour' patterns within the Aurora parallel programming system. Scoped behaviour is an application programmer's interface to a set of system-provided optimizations; it is also an implementation framework for the optimizations. Aurora is a distributed shared data system where shared-data objects are implemented in connected by an ATM network. The design, implementation, and evaluation of Aurora and scoped behaviour contributes to the field of parallel and distributed systems by demonstrating that: (1) Scoped behaviour can provide per-object and per-context (i.e., specific portion of the source code) flexibility when applying data-sharing optimizations. In contrast to some other systems, Aurora programs can be incrementally tuned and only a minimum number of error-prone changes to the source code are required in order to experiment with different optimization strategies. (2) Scoped behaviour can be implemented without language extensions and without special compiler support. Scoped behaviour's novel implementation framework can exploit both compile-time and run-time information about the parallel program. (3) A parallel programming system based on a high-level of four applications implemented using three different types of parallel programming systems, Aurora usually matches or outperforms, sometimes by a wide margin, TreadMarks (a distributed shared memory system) and a message-passing system (either MPICH or PVM, depending on the application).
An ethnographic study of homeless youth, the food experiences of squeegee kids

Current knowledge about food insecurity In North America is based on research with low-income households. The experiences of homeless people, a segment of the population who are particularly vulnerable to food insecurity, have been largely ignored by nutrition researchers. In this study, the food experiences of street youth, one of the fastest growing segments of the urban homeless population, were explored. To gain an understanding of their context-driven food experiences a critical ethnography was conducted. Over a five month period, field notes from weekly participant observation sessions with street youth at an inner-city drop-in centre in Toronto were compiled, and interview data were collected from six of these youth. Results of this study revealed that food access was precarious amidst the instability and chaos of street life. Further, in the context of homelessness, food was inextricably linked to and contingent upon other survival needs such as income, health, and shelter.
Development of tools to assess the role of arylamide deacetylase in arylamine biotransformation and toxicity

The goal of the present work is to develop tools to aid in the elucidation of the role of DAC in the pharmacological, toxicological, and carcinogenic effects observed following exposure to arylamines. We devised a sensitive HPLC assay to monitor deacetylation activity, and raised a high-titre polyclonal anti-human DAC antiserum that enables the detection and quantification of immunoreactive protein with high sensitivity and specificity. Heterologous expression of DAC was also attempted with both bacterial and mammalian expression systems. Difficulties were encountered in creating the expression systems, and functional protein could not be obtained. One possibility for this difficulty in heterologous expression is that functional DAC protein has a deleterious effect on the expression host cells. Finally, DNA sequencing of these clones revealed that the published DNA sequence of DAC is incorrect.
Canada and culture, can current cultural policies be sustained in the global trade regime?

This thesis examines certain examples that are representative of the Canadian federal government's current framework supporting the Canadian cultural industries with a view to determining whether these policies can be maintained within the global trading regime. These policies are examined in light of the relevant provisions of the GATT, the GATS and the NAFTA, as well as the proposed Multilateral Agreement on Investment. Three cases are investigated including: the provisions of the agreement between Canada and the United States resolving the magazine dispute; the CBC proposals to the CRTC concerning the future of the CBC; and the recommendations regarding the Canadian film industry put forward by the Feature Film Advisory Committee. The investigation of these cases reveals that current Canadian cultural policies may be coming perilously close to violating Canada's commitments to trade under the international agreements. Prior to the analysis of the above cases, current policies and programs within the periodical publishing, film and video and public television broadcasting industries are examined so as to provide a context for the analysis of the above cases.
The play is the thing, an investigation of play-based learning strategies

An emphasis on the mastery of specific information may be exclusive of effective methods of discovery, expression and understanding. To investigate, an exploration of the effect of play based learning strategies, relative to addressing the curriculum expectations of the Ontario Ministry of Education in the Social Sciences, was undertaken. The qualitative research methodology utilized elite interviews, student surveys and researcher field notes to acquire data from events arising from the deployment of an arts based research unit in grade eight history. Quantitative and qualitative data were analyzed together with phenomenological considerations of the researcher's involvement and aims. Results of the investigation included the discovery that a play based strategy such as drama is highly regarded by teachers because it can motivate students and promote multidimensional involvement in learning. Also revealed was that such strategies are seldom utilized because of teachers' concerns with their skill in this area, student behaviour, time limitations and issues of evaluation.
Design of a programmable switched-capacitor analog FIR filter

The use of an analog adaptive filter can offer benefits over a digital adaptive filter in application that require high-speed, low-power, and a moderate degree of linearity. An adaptive digital FIR filter will typically be implemented as a finite impulse response filter using a pipelined tapped delay fine with programmable tap coefficients. When an analog adaptive filter is constructed, a parallel tapped delay line is used. A programmable analog FIR will typically use buffered sample-and-hold blocks for the analog delay line and transconductors to implement the MDACs used for the tap coefficient multiplication. The research focusses on a more passive approach to the circuit realization. An entirely voltage-mode, switched-capacitor implementation is presented. A seven tap adaptive analog FIR filter using the passive architecture is realized in an area of 1.44mm2. The fabricated chip has a power dissipation of 104mW using a sampling frequency of 200MHz and a power supply of 3.3V.
Extended Moore automata for the supervisory part-flow control of virtual manufacturing workcells

Flexible manufacturing workcells for discrete production usually exhibit the characteristics of a discrete-event system (DES). In the past, workcells have been sufficiently simple that intuitive and ad-hoc control solutions have been adequate. However, the increasing complexity of these systems has created a need for formal approaches for their analysis and control. A variety of methodologies, such as Petri nets and Ramadge-Wonham automata have been proposed to address the control of DESs within a formal theoretical framework. Traditionally, the objective of a workcell supervisor has been to control the discrete-event system according to manufacturing constraints and parts to be produced. In the DES supervisory-control theory, the main challenge is to synthesize a supervisor that confines the DES to a specific behavior, determined by a set of specifications. Using this theory, when any of the system's specifications changes, a new supervisor must be synthesized, which may take a considerable amount of time. In a Flexible-Manufacturing Workcell (FMC), however, it is common to frequently change the set of part types to be manufactured and/or the set of machines used to produce the parts, i.e., changing the set of specifications. Since such changes usually occur on a temporarily basis, the efficiency of traditional workcells can be increased via the utilization of virtual flexible-manufacturing workcell concept. Unlike traditional workcells, virtual workcells may be re-configured by either (i) adding to or removing from it machines, or (ii) rerouting through it parts which have not been a priori planned for. Past workcell-supervisor-synthesis methodologies have not considered the supervisory control of such workcells. This thesis address four basic supervisory-control problems for the autonomous control of workcells that can cope with parts having alternative routes which may share resources with other workcells, and be temporarily expanded by the introduction of either new part types or new machines into their nominal configurations. These are the building blocks necessary for the control virtual workcells. The proposed control techniques use Extended-Moore Automata (EMA) and Ramadge-Wonham theories to synthesize deadlock-free supervisors. The use of EMA also allows the minimization of the state-space of supervisors, which has been a fundamental problem in DES control. Moreover, the proposed supervisor techniques allow the automatic implementation of the (EMA-based) supervisors using commercial controllers such as industrial Programmable-Logic Controllers (PLCs). The supervisor synthesis methodologies proposed in this thesis have been verified to be viable techniques through their actual implementation using an experimental robotic workcell. Different EMA-based supervisors have been successfully implemented using a user-friendly supervisory-control software package developed in our laboratory for MS-Windows environments.
Word analysis skills, a study of grade 10 core French students' knowledge of derivational morphology in their second language

Vocabulary knowledge is very important for reading in a second language. Many words encountered by L2 learners are not in their oral vocabularies, but their meanings can often be deduced because they are related to familiar L2 words through prefixation, suffixation, compounding, or through L1 (cognates). Studies show that learners who possess good word analysis skills are better readers. It is thus important to help students develop these skills to the fullest. In current core French materials, little attention is paid to the development of word analysis skills. The goal of this study is to find the extent of grade 10 core French students' current knowledge of derivational morphology in French in order to provide practitioners in the field with diagnostically useful information that can be used as a basis for choosing appropriate reading materials, and for the development of learning materials focusing on word recognition strategies or skills.
Moral authority as a power resource

For many years the International Relations community has treated the question of why states choose to change the behavior as unproblematic. Rationalist theories of international relations have conditioned us to think that states act only in response to threats and incentives as their capacity to survive in the international system is affected. Not only have recent upheavals within the discipline allowed the reconsideration of these assumptions but the impetus to look at this question has been heightened by what appears to be anomalous state behavior. Press reports and public discussions have strongly suggested that non-state and transnational actors can play a fundamental role in changing state behavior, especially at global issues conferences and in conflict and crisis resolution. There has been very little serious evaluation of the power of transnational moral authorities. On the basis of circumstantial evidence and in light of the theoretical space created by the recent trend in academic international relations to treat the state as a socially constructed actor, this would seem to be a suitable opportunity to explore some ideas about moral authority and its impact on state behavior. Primarily, my interest is in whether morally authoritative transnational actors can influence state behavior. However, in the course of this inquiry it should also be possible to gauge to what extent moral authority can be used as a power resource. If, for example, states are unwilling to bend to the wishes of a transnational actor then moral authority cannot be considered as an effective power resource, but if states bend readily and quickly then moral authority is clearly a neglected source of leverage that needs to be incorporated into the definition of power. Then, there is always the middle ground, where states are receptive to moral suasion but not to the extent that the transnational actor would desire. From this mixed outcome it is possible to suggest what factors would affect the ability of the transnational actor to use moral authority as a power resource. This will lead to the creation of a new research project to identify the conditions that affect the degree of leverage that transnational actors can exercise over states.
A CMOS DVD 4x Viterbi detector, system design and VLSI implementation

DVD represents the current state-of-the-art in consumer read-only optical storage, and read channel data rates are constantly being pushed higher. At higher data rates, impairments limit the usefulness of traditional slicer based methods of data detection. Also, intersymbol interference degrades the slicer error performance. This thesis examines Viterbi detection, which improves bit error rate, for a 4* (104.64 Mbps) DVD read channel. A model of the DVD read channel is presented, and used as the basis for designing a Viterbi detector that exploits the channel characteristics such as run-length limited coding constraints. An architecture implementing the detector is developed, as well as a 0.35 [mu]m, 3LM, CMOS implementation with a core area of 0.62 mm2 and total area of 5.4 mm2, which is expected to run at 4x data rates.
Exploring Qualitative Probabilities for image understanding

In this thesis we explore and work with a particular probabilistic framework for image interpretation called Qualitative Probabilities. Introduced by Jepson and Mann, Qualitative Probabilities formalize the notion of non-accidentalness, a cornerstone of object recognition. First we examine the search space associated with Qualitative Probabilities. We also experimentally verify one of the underlying principles of the theory, the asymptotic rate of 'accidents'. Then we incorporate Qualitative Probabilities into a relatively simple search which we find to be efficient and effective. Comparing search for interpretations using Qualitative Probabilities to search using a more standard 'cover' measure, we find that the former is far superior both in terms of efficiency and quality of block models found. Lastly, we design and test a new search algorithm, called Cascade search that uses Qualitative Probabilities.
The effects of tarsal tunnel release and stabilization procedures on tibial nerve tension in a surgically created pes planus foot

An in vitro study was performed on 11 cadaver legs to study the effects of tarsal tunnel release, distraction calcaneocuboid arthrodesis, and triple arthrodesis on tibial nerve tension in surgically created pes planus feet. Tibial nerve tension was measured during dorsiflexion, eversion, combined dorsiflexion-eversion, and cyclical load with 0$\sp\circ$, 15$\sp\circ$, and 25$\sp\circ$ of internal rotation, and repeated on the same leg following each surgical procedure. A pes planus deformity significantly increased tibial nerve tension compared to baseline for all foot positions and cyclical load. A tarsal tunnel release significantly increased nerve tension during eversion, dorsiflexion-eversion, and cyclical load compared to the pes planus foot. A triple arthrodesis more effectively decreased nerve tension than a distraction calcaneocuboid arthrodesis. Procedures producing skeletal instability (pes planus deformity and a tarsal tunnel release) increased tibial nerve tension. Procedures which corrected deformity and increased stability, decreased tibial nerve tension. In pes planus feet, if increased tibial nerve tension contributes to tarsal tunnel syndrome, then treatment with orthotics should be exhausted before considering surgery, which can further increase nerve tension.
Defensins, endogenous antibiotic peptides in the human mammary gland

The entirety of milk's antibacterial factors has not been elucidated. Of particular interest is a class of endogenous antibiotic peptides shown to be present in several of the body's epithelial tissues, called defensins. We hypothesized that ß-defensins are produced and secreted by mammary gland epithelia, thus preventing local infection of the breast and/or contributing to feeding-mediated passive immunity for the neonate. Using RT-PCR, we identified the human defensin-1 gene transcript in a mammary epithelial cell line (MCF-12A) and in mammary gland tissue of non-lactating women. Expression of hBD-1 was also found in milk epithelial cells. Furthermore, presence of the hBD-1 peptide in mammary gland epithelia was established by immunostaining. RT-PCR analysis of the relative levels of expression in murine mammary gland revealed that ß-defensin mRNA expression is highest during pregnancy and lactation. Our findings suggest that ß-defensins play a biological role in the mammary gland.
Implementation of a fully depleted Delta-channel SOI NMOSFET

Silicon-On-Insulator (SOI) CMOS technology is a potential technology for future VLSI system implementations. Owing to complete dielectric isolation, SOI technology offers superior MOS devices with suppressed CMOS latch-up, higher packing density and higher speed. SOI fully depleted ultrathin-film MOSFET structures offer many advantages including ideal subthreshold slope, reduced floating body effects, superior transconductance and superior current drive. However, stringent control of silicon film uniformity is needed. In this thesis, a fully depleted [Delta]-channel SOI NMOSFET structure is proposed. The key feature is the triangle-shaped channel implemented in a thick SOI film using anisotropic etching technique of silicon. The gate electrode exhibits an improved control over the channel potential and entire depletion of the channel is obtained. The proposed structure eliminates floating body effects and works in fully depleted regime with bulk effective mobility in the channel region. A CMOS-compatible process for the fabrication of the proposed A-channel SOI NMOSFET was developed. The device was successfully manufactured and electrically characterized. The [Delta]-channel SOI NMOSFET exhibited a threshold voltage of 370 mV and an excellent subthreshold slope of 67 mV/dec. No kink was observed in the output characteristics. Enhanced transconductance and current driving capability were observed due to bulk mobility in the channel. Floating body effects were substantially suppressed and fully depleted SOI MOS performance was achieved.
The synthesis of the C24-C32 subunit of (+)-ionomycin

Described herein is the Lautens/Colucci total synthesis of (+) ionomycin, with specific attention being paid to the synthesis of the C24-C32 tetrahydrofuranyl subunit. To date, two previous total syntheses of (+) ionomycin, to be discussed, have been published by the groups of Evans and Hanessian. Also described is the general chemistry of the formation of tetrahydrofuran rings. This tetrahydrofuranyl subunit, ring B of ionomycin, is derived from a geranyl acetate backbone. Sharpless asymmetric epoxidation and a diastereoselective epoxidation-cyclization sequence are the key manipulations applied to install the desired stereocentres. Each of the other three acyclic fragments of ionomycin arise from exploitation of the versatile chemistry of (3.2.1) oxabicycles. Chemistry developed in this laboratory which provides enantiospecific nucleophilic ring opening effects further skeletal elaboration.
Cold-evoked pain varies with skin type and cooling rate, a psychophysical study in humans

This thesis examined the effect of skin type and cooling rate on the intensity, quality and time-course of cold-evoked pain in normal human subjects. Cold stimuli were delivered to the thenar eminence (glabrous skin) and the dorso-lateral hand (hairy skin) via a 9cm$\sp2$ Peltier-type stimulator. Cold and pain thresholds were determined by the method of limits. A computerized visual analogue scale was used to obtain continuous ratings of pain intensity and affect. The McGill Pain Questionnaire was used to assess the quality of cold-evoked pain. Supra-threshold stimuli (34$\sp\circ$C base) were delivered at 0.5, 1 or 2$\sp\circ$C/s to 2$\sp\circ$C, held for 20s and returned to baseline at 9$\sp\circ$C/s. These studies revealed: (1) Cold and cold-induced pain thresholds were lower (e.g. occurred at a higher temperature) for hairy compared to glabrous skin. (2) Power function exponents for supra-threshold ratings were larger for glabrous skin than for hairy skin. (3) Pain indices were higher for slower cooling rates. (4) No differences were found for pain ratings of intensity and affect. (5) Cold-evoked painful paradoxical heat sensations occurred most often during innocuous cooling.