VictorJuiz/thesis huggingface dataset:
Princess Point, the landscape of place

The 'Landscape of Place' is an interpretation of Princess Point settlement as an expression of the surrounding landscape. Princess Point is a proto-Iroquoian group, who may or may not be direct ancestors of Ontario Iroquois, that occupied southwestern Ontario 'circa' A.D. 500 to 1050. This dissertation defines and models the Princess Point settlement system with emphasis on the relative contributions of activities associated with a period of sedentarisation, social re-organisation, and subsistence change in the form of maize cultivation activities. The research objective of this dissertation uses a substantive evaluation of the Princess Point settlement system through spatial and temporal modelling of the interrelationships between archaeological sites and the environment. The research objective also uses an inferential explanation of the Princess Point settlement system through spatial and temporal modelling of the interrelationships between space and place. The data sources include a cross section of 45 sites from Princess Point, Middle Woodland, and Glen Meyer cultures southwestern Ontario, and 10 random locations in the lower Grand River valley, analysed through geographic, topographic, water, and soil landscapes. Landscape modelling illustrates the relationships between a community and its surroundings. These relationships are presented through the format of a viewshed in this dissertation, suggesting the recreation of a community's perception of their immediate landscape. The landscape approach presents site location preferences as cultural decisions based on both economic needs and socially determined needs. The landscape model, as applied to the Princess Point culture, is used to explain the effectiveness of applying a landscape methodology to prehistoric data sets in southern Ontario. Princess Point site distribution follows a newly evolving pattern, whereby a bounded orientation is repeated at all scales. Discrete clusters consist of naturally bounded communities and oriented towards water resources. Sites with rich, yet restricted, resource zones are in association with immediate access to productive soils, placing a greater emphasis on cultivated resources. The 'Landscape of Place' highlights the fulcrum of the shift from people living in the landscape to people living on the landscape.
Influence of boundary conditions on an ultrasound backscattering model of blood

A simulation model of one-dimensional (1-D) ultrasound propagation in blood was used to study the relation between the backscattering coefficient and hematocrit. In this model, an ultrasonic plane wave is propagated normal to randomly placed slabs of constant thickness whose acoustical properties are the same as red blood cells and plasma, and the corresponding intensity reflection coefficient was calculated. The simulation results were compared to a model based on the Percus-Yevick (P-Y) theory as presented in the literature. Previous investigators have reported a close agreement over a limited range of simulation parameters between their results and the P-Y theory. However, a more careful investigation using a wider range of parameters revealed major discrepancies. It was shown that these arose from an inappropriate choice of boundary conditions. Averaging the acoustic properties beyond the boundaries of the simulation, as suggested by earlier theoretical work, resulted in an excellent agreement with the P-Y theory over a wide range of simulation parameters.
Bone tissue engineering on biodegradable polymers

This thesis presents work on the use of biodegradable, biocompatible polyesters for bone tissue engineering applications. New processing routes to create open-cell foam structures using polyesters were developed. The design of these new foams was based on the morphology of trabecular bone. Highly interconnected pores in the millimeter range or larger, were created and bone cell growth and differentiation within these structures were investigated. To identify an appropriate biocompatible, biodegradable polymer, initial studies investigated poly(lactide-co-glycolide)s (PLGA)s with different ratios of lactide:glycolide as thin films. Bone marrow cell differentiation and matrix elaboration on the polymer surfaces were monitored by tetracycline staining. It was demonstrated that PLGA 75/25 was the best substrate for cell proliferation and matrix formation of the biodegradable polymers investigated. PLGA 75/25 was then used to prepare 3-D open-cell foam structures similar to the isotropic regions of trabecular bone. A new foaming protocol, namely a phase-inversion particulate-leaching process, was developed. New foam structures were created and characterized for pore size, pore wall thickness, pore interconnectivity and mechanical behaviour. A degradation study of the new foam structures was conducted. PLGA 75/25 foams, degraded at pH 5.0, 6.4 or 7.4, maintained their 3-D morphology for at least 4.5 months. This result indicated that the rate of foam degradation ' in vitro' is likely slower than that of bone formation 'in vivo'. Bone marrow cells differentiated into osteoblasts and grew throughout the 3-D foams. The effect of different foam morphologies on cell colonization of the scaffolds was studied and the morphological requirements for a 3-D structure to serve as a scaffold for bone tissue engineering were established. Future work includes research on bone growth throughout the foam structures ' in vivo'. Preliminary 'in vivo' results indicate that new tissue formed throughout the entire foam structures retrieved from the rat femora.
Modelling the behaviour of microbubble contrast agents for diagnostic ultrasound

Encapsulated microbubble contrast agents that can be injected intravenously constitute one of the most important developments in recent years in ultrasound imaging. These microbubbles oscillate nonlinearly in ultrasound fields and produce nonlinear echoes which can be detected by novel imaging methods. The performance of these novel methods depends strongly on the characteristics of nonlinear scattering by the bubbles. Currently a systematic approach to optimizing them does not exist. This is due in part to the lack of a theoretical model for predicting the acoustic response of microbubble contrast agents. This thesis presents some developments made to address this deficiency. A theory for the nonlinear motion of a single bubble formed the basis of this study. The model was extended to account for the multiplicity of bubble size and the heterogeneity of the ultrasound field. Experiments were designed and performed to quantitatively test the model. The results generally confirmed the validity of the model, while some quantitative discrepancies led to the hypothesis that the shell plays an important role in nonlinear scattering, which was also confirmed by experiment.
Physical, chemical, soda pulping and papermaking properties of Kenaf as a function of growth

Kenaf (Hibiscus canabinus) is a promising non-wood plant fibre that can serve as a source fibre for pulping and papermaking. Because the chemical and physical composition of the plant changes as the plant develops, research is needed to determine its pulping properties at various stages of growth in order to establish the optimum harvesting time. In the present work, the chemical composition and pulping properties of kenaf as a function of growth have been studied. Kenaf plants were harvested at the end of 90, 120, 150, and 200 days (maturity). Extractive-free ground samples of the stem were cooked at three different temperatures of 140$\sp\circ$C, 155$\sp\circ$C, and 170$\sp\circ$C, using soda cooking liquor of 32 g/L NaOH, with an active alkali charge of 15% as Na$\sb2$O, and liquor to wood ratio of 6:1. The chemical analysis shows that the differences in holocellulose and lignin content for 90, 120, and 150-day old kenaf are not significant, while 200-day-old kenaf is significantly different from others. Micro-pulping properties of kenaf at various stages of growth are also not significant. However, statistically significant differences were observed in terms of physical properties of kenaf pulps. In comparing the fields of kenaf pulps, it is observed that the average yield for 150-day-old kenaf, over the whole range of cooking times and temperatures studied, is highest (60.4%) amongst the group. Kenaf can be harvested at the end of 150-day growth period, based on the results of chemical analyses to achieve higher yield, with reasonably lower lignin content. Since 90-day-old kenaf showed highest breaking length and stretch values, kenaf may also be harvested at the end of 90-day growth period, based on the physical properties of kenaf pulps. This may also allow to obtain 2-3 crops per year depending on the location.
Multi-station injection molding, design and analysis using evolutionary algorithms

A tool to facilitate the feasibility study of a newly proposed multi-station injection molding system is developed. The conceptual design and proposed embodiment of the new system are geared toward the development of a system flexible enough to handle multiple part types and production volumes. A comprehensive design model is used to structure the problem. Two customized Evolutionary Programming algorithms are used to optimize the new and traditional system configurations. The systems are compared in their ability to satisfy a range of production requirements captured by the 54 trials of a full factorial design of experiments. Results indicate that the multi-station system outperformed the traditional system in at least 57% of the trials confirming the viability of the new system. Furthermore, an analysis of variance indicates that the factors part thickness, projected area, production volume and part variety significantly affect the cost differential between the two systems.
Nothing personal?, narrative reconstruction of Registered Nurses' experience in healthcare reform

My research is an inquiry into how it matters to explore Registered Nurses' experience in healthcare reform through narrative reconstruction autobiographically and biographically with other nurses. Narrative inquiry, a phenomenon and method that informs nursing praxis (being-becoming, knowing, and doing), is ontologically related to shaping nurses' identity and is concerned with epistemology, nurses' knowledge. A comparison and contrast to phenomenological research in nursing education reveals how narrative inquiry contributes through the inclusion of the researcher with co-participants in the construction of identity and knowledge in three dimensional space. Individual and social aspects of experience, temporality, and place are considered. Examination of plotlines in healthcare reform literature and research reveals only the negative effects of restructuring and includes top-down strategies. In contrast, seven co-participants in my inquiry illuminate the healthcare professional knowledge landscape through their stories of experience. The notion of liminal space, holding paradox in-between stories, is explored. Sasha, a co-participant in my inquiry, is a nurse in clinical practice who is also a student in a BScN program. How it matters to have a story to live by in healthcare environments undergoing many changes is shown through Sasha's reflection on and reconstruction of experience through two years of conversations. Narrative inquiry offers nurses a way to think about their experiences, to reflect in relationship, and to discern future possibilities for reform that is inside-out, grounded in daily life. How my inquiry matters to nurse-teachers and to nursing education at the university is presented through conversation with three colleagues at a reading luncheon. My inquiry deepens and new questions emerge related to nursing education and nursing praxis embedded in the relationships between nurses and their social situations.
Reduced-complexity noncoherent receiver for GMSK signals

Gaussian Minimum Shift Keying (GMSK) is a spectrum and power efficient modulation scheme, used in many wireless communication systems. Since GMSK is nonlinear, the receiver for GMSK signals is more complex than that for linear modulation signals. A reduction in complexity can be achieved by employing a noncoherent signal detection scheme. In this thesis, a reduced complexity noncoherent GMSK receiver, using the Laurent representation and noncoherent Decision Feedback Equalization (DFE), is proposed and evaluated first in an Additive White Gaussian Noise (AWGN) channel. The Bit Error Rate (BER) performance of the proposed receiver is compared to a corresponding coherent receiver. Furthermore, the proposed receiver is evaluated in static Finite Impulse Response (FIR) channels and multipath Rayleigh fading channels. The effects of two intrinsic parameters on performance are examined. It is concluded that the proposed receiver is a high performance noncoherent receiver when compared to other known noncoherent GMSK receivers.
The function of neuralized during Drosophila development

Initially identified as a group of genes affecting 'Drosophila ' embryonic nervous system development, the neurogenic genes have since been shown to encode components of a highly conserved signaling pathway essential for many developmental processes (Chan and Jan, 1999; Greenwald, 1998; Lewis, 1998). Best characterized for their role in cell fate determination, the neurogenic genes have also been shown to be important for events such as cell differentiation, establishing tissue polarity, establishing compartment and controlling tissue growth. The fact that neurogenic genes participate in a variety of developmental processes in many diverse species, emphasizes the need to understand pathway functions. While many of the main components within the signaling pathway have been identified, understanding of the mechanism of neurogenic signaling remains incomplete. Activation of the pathway involves the interaction of two transmembrane proteins, 'Delta' ('Dl') and 'Notch' ('N'), initiating a series of events that ultimately lead to transcription of downstream genes. Studies are beginning to reveal the nature of these events and the genes that are responsible for transducing the ' N' signal to the nucleus. One of the genes that appears to be necessary for neurogenic signaling is the gene 'neuralized' (' neu'), which encodes a RING finger domain-containing protein. The function of 'neu' within the signaling pathway, however, is unknown. In addition, the role of 'neu' throughout development has not been well characterized. This thesis reports the role of 'neu' during ' Drosophila' development, and its function within the neurogenic signaling pathway. Using mosaic analysis, a role for 'neu' in the development of bristle sense organs is described in chapter 2. These data demonstrate that 'neu' functions during the determination and differentiation of sense organs, and that 'neu' functions cell autonomously to transduce or propagate 'N' signaling. As well, the subcellular localization of the Neu protein at the plasma membrane is demonstrated. In chapter 3, various 'neu' constructs are used to demonstrate that Neu is an E3 ubiquitin ligase and that ubiquitin ligase activity is conferred by the RING finger domain. Taken together, the results of these studies suggest that Neu functions to positively transduce the 'N' signal by targeting membrane-associated components of the neurogenic signaling pathway for ubiquitination. In appendix A, the clonal analysis is each to characterize the role of 'neu' during the eye and wing development. Preliminary evidence suggests that 'neu' functions during ' N' signaling throughout 'Drosophila' development. However, an investigation of the role of 'neu' during oogenesis shows that the function of 'neu' may be redundant or dispensable for some 'N' signaling eves. This knowledge provides a basis to begin investigating not only the exact role of 'neu' in ' N' signaling, but how ubiquitin can be used to transduce signals in general.
The effect of spatiotemporal sampling strategies and data acquisition accuracy on the characterization of dynamic ecological systems and their behaviours

This study examined the effects of spatial sampling strategies on the description of complex environmental systems in the presence of measurement error. A simulation experiment approach was used since field experiments are prohibitively expensive and analytical solutions are generally intractable for realistic ecological complexity. A two-species patch occupancy model was constructed that included a spatially structured substrate, climatic influence on resources, and species-independent response to resources and disturbances. The model was executed using a broad range of resource patterns and species characteristics. Software instruments simultaneously collected data from the simulation world according to a prescribed set of sampling strategies and degrees of measurement accuracy. Resource inventories and species frequencies were estimated using the simulated "field" data and then compared to the "true" state of the simulation world. The spatial sampling pattern (random or gridded) only affected estimates when the analysis method explicitly used spatial information, in which case gridded samples produced lower magnitudes of error but random samples produced the smallest, most consistent bias. For aspatial analyses, the mean difference between estimates using each sampling pattern were within 3% of each other. Aside from spatial sampling pattern, the spatial sampling density was the most influential design factor for resource inventories. The errors in individual measurements were strongly reduced upon aggregation and had only a minimal effect on the overall inventory estimates. A threshold effect appeared in census estimates at a spatial sampling density of 0.05, relative to grid cell size. Estimates from sparser samples (typical of most census efforts) were dominated by spatial density itself. Denser samples were predominantly influenced by classification accuracy. At the greatest spatial densities (0.15 or greater), an increase in density resulted in a larger census error if not accompanied by an increase in classification accuracy. The experiment results suggest that field exercises should be planned to maximize mobility and coverage density, with less emphasis placed on obtaining the most accurate measurements possible. Inexpensive sensors that allow rapid measurement with moderate accuracy, combined with mobile computing and GPS units for rapid spatial data acquisition, should produce the most effective data for characterizing overall system state.
Development of a novel test protocol for assessing visuospatial function in a canine model of aging

We have been developing a canine model of human aging and dementia over the past decade. Previously, we have characterized age-related decline in visuospatial ability using a two-position delayed non-matching-to-position (2-DNMP) task. However, the 2-DNMP is vulnerable to orientation strategies, which reduce mnemonic loads. Consequently, we developed a three-position DNMP (3-DNMP) task. Larger age-differences are found with the 3-DNMP task than on the 2-DNMP task with the majority of aged canines unable to solve the task. The disparity may be the due to the requirement of a cognitive (rule-based) strategy in the 3-DNMP task, whereas the 2-DNMP can be solved with a stimulus-response (procedural) strategy. However, we did find that aged canines could successfully acquire the 3-DNMP task if they are first trained on the 2-DNMP task. It may be that the increased complexity of the 3-DNMP task overwhelms capacity of aged dogs to determine the relevant tasks components.
Microbiological investigations of geophgay in chimpanzees

Chimpanzees in East Africa are known to eat soil from Macrotermitinae mounds, but the reasons for and possible benefits of this behaviour are not well-understood. The purpose of this project was to use a microbiological approach to study geophagy. More specifically, it was to examine soils eaten by chimpanzees (Pan troglodytes schweinfurthii) in the Mahale Mountains and Gombe areas of Tanzania to determine if the soils had a characteristic or unusual microflora. Results showed higher numbers of bacteria and lower numbers of fungi in most termite mound soils compared to control soils. These findings can be correlated to the activities of the termites and the clay mineralogy of the soils. The most commonly isolated fungal genus was Penicillium with over 500 isolates and 44 species. Penicillium citrinum was isolated almost exclusively from termite mound soils and is considered a dominant member of the community. Termite mound soils were found to exhibit greater similarity to each other than to control soils in fungal species composition.
Effect of local anaesthetic block on neurogenic temporomandibular inflammation

Temporomandibular joint (TMJ) disorders and rheumatoid arthritis are two conditions in which neurogenic mechanisms are purported to play a critical role. The purpose of this study was to investigate the neurogenic contribution underlying acute TMJ inflammation by evaluating the effect of local anaesthetic blockade of afferent innervation on the development of mustard oil (MO) induced edema in the rat TMJ area. Adult male Sprague-Dawley rats were anaesthetized by intraperitoneal Ã-chloralose and urethane. Saline injection into the right TMJ followed by MO (1% to 60%) 6 minutes later elicited dose-dependent edema development. Lidocaine (5%) or bupivacaine (0.5%) followed by MO (1% or 40%) did not produce edema development different from saline controls (p < 0.05, Repeated measures ANOVA). Two conclusions may be drawn. First, MO acts non-neuronally contrary to traditional perceptions or second, MO selectively elicits edema through neurogenic mechanisms and therefore suggests a role for neurogenic mechanisms in acute TMJ inflammation.
Modeling in extrusion cooking of breakfast cereals

This project is part of a long-range research program to develop a thorough understanding of the effects of pretreatment and cooking extrusion on the structure of starch polymers. Residence time distributions were measured using two different tracers in order to determine processing time characteristics, flow patterns as well as mixing efficiency in the preconditioner and in the preconditioner-extruder system. The results indicate that there is poor mixing in the preconditioner which carries through the extruder. An improved technique for obtaining RTD was developed. The technique clearly demonstrated that the pre-mixer provides poor mixing if two particle populations with distinctly different particle size are present. The material flow inside the system can be described by two simultaneous mechanisms. Part of the material moves through an active volume, while the reminder, 10 to 30%, was held up in the dead space.
Regulation of prostaglandin production in the ovine placenta

Recent evidence suggests ovine intrauterine prostaglandin (PG) production rises through late gestation due to a direct effect of cortisol on PGH synthase type-2 (PGHS-2) expression and activity within placental trophoblast tissue. Ovine trophoblast cells were isolated, cultured and treated with cortisol. PGE2 output increased towards term and with cortisol treatment. Synthesis of PGE2 is also dependent on PGE synthase (PGES), which converts PGH2 to PGE2. We examined the expression of PGES in the ovine placentome through gestation, labour, and with cortisol treatment. Immunoreactive-PGES protein was localized to fetal trophoblast tissue and endothelial cells of maternal vessels. PGES mRNA and protein increased with gestation, however, there was no significant change with labour or cortisol-infusion. In summary cortisol directly increased PGHS-2 activity 'in vitro ' and 'in vivo' PGES expression was found to rise with gestation. Together the rise in these two enzymes in late-gestation may function to increase PGE2 levels to term.