Cell behavior is influenced to a large extent by the surrounding microenvironment. Therefore, in the body, the cellular microenvironment is highly controlled with cells growing within well-defined tissue architectures. However, traditional culture techniques allow only for the random placement of cells onto culture dishes and biomaterials. Cell micropatterning strategies aim to control the spatial localization of cells on their underlying material and in relation to other cells. Developing such strategies provides us with tools necessary to eventually fabricate the highly-controlled microenvironments found in multicellular organisms. Employing natural extracellular matrix (ECM) materials in patterning techniques can increase biocompatibility. In the future, with such technologies, we can hope to conduct novel studies in cell biology or optimize cell behavior and function towards the development of new cell-based devices and tissue engineering constructs. Herein, a novel cell patterning platform was developed on a hydrogel base of crosslinked hyaluronic acid (HA). Hydrogels are often employed in tissue engineering due to their ability to mimic the physicochemical properties of natural tissues. HA is a polymer present in all connective tissues. Cell-adhesive regions on the hydrogel were created using the RGDS peptide sequence, found within the cell-adhesive ECM protein, fibronectin. The peptide was bound to a 2-nitrobenzyl “caging group” via a photolabile bond to render the peptide light-responsive. Finally, this “caged” peptide was covalently bound to the hydrogel to form a novel HA hydrogel with a cell non-adhesive surface which could be activated with near-UV light to become adhesive. In this way, we successfully formed chemically patterned cell-adhesive regions on a HA hydrogel using light as a stimulus to form controlled cell patterns. While the majority of cell patterning strategies to date are limited to patterning one cell population and cannot be changed with time, our strategy was novel in using small, adhesive, caged peptides combined with multiple, aligned light exposure steps to allow for dynamic chemical cell patterning on a hydrogel. Multiple cell populations, even held apart from one another, were successfully patterned on the same hydrogel. Furthermore, cell patterns were deliberately modified with time to direct cell growth and/or migration on the hydrogel base.

A study was undertaken of plants used for treatment of diabetic symptoms by traditional healers of the Eeyou Istchee Cree (Canada), Lukomir Highlanders (Bosnia & Herzegovina), and Q’eqchi’ Maya (Belize). All antidiabetic plants were ranked by syndromic importance value (SIV) based on 15 symptoms, all of which were recognized by the Cree and Maya and 8 by the Highlanders. The Cree used only 18 species, the Highlanders 41, and the Maya 150, numbers which reflect the diversity of flora in their region. Vaccinium (Ericaceae) was one of the few genera in all three regions and the only consensus genus between the Cree and Highlander study sites. The Q’eqchi’ Maya ethnobotany did not present any cross-cultural consensus genera with Cree or Highlander medicinal plants, perhaps due to major biogeographic differences. In ethnopharmacological studies, Vaccinium species and Q’eqchi’ antidiabetic plants were tested in an assay relevant to diabetes, the advanced glycation endproduct (AGE) inhibition assay. Boreal and tropical Vaccinium species were potent inhibitors of AGEs and demonstrated concentration dependent inhibition, with a half maximal inhibitory concentration (IC50) range of 5.93–100 µg/mL. Phenolic content ranged from 80.3 to 201 µg/mL in boreal samples and from 1470 to 2170 µg/mL in tropical samples. Tropical species have a greater phenolic content and AGE inhibition. Seven Q’eqchi’ antidiabetic plant species were tested and all plant extracts showed AGE-inhibition. The IC50s ranged from 40.8 to 733 µg/mL, and the most active was Tynanthus guatemalensis Donn.. Tynanthus guatemalensis IC50 was about fives times greater (less active) than the mean ± SE IC50 reported for six tropical Vaccinium species of Vaccinium (8.77 ± 0.79 μg/mL). The highest consensus and most active Maya antidiabetic plant, Tynanthus guatemalensis Donn. Sm. was discovered to be an important plant recorded in archeological artifacts from the Late Classic Maya period (~750 CE). Ancient Maya used a cross shaped sign (k’an glyph) as a decorative element on Late Classic polychrome vessels and murals. The sign was believed to be the xylem template for a plant used as a flavouring in cacao drinks. However, the plant was incorrectly identified in the literature as Pimenta dioica (L.) Merr. (common name: Allspice) based on a common name and aromatic plant quality – not from a botanical voucher specimen. Pimenta dioica wood does not have a cross shape visible in the xylem but a unique character visible after a cross section of T. guatemalensis, is the xylem's cross shape organization. Wood of T. guatemalensis' also has an "allspice" aroma. Tynanthus guatemalensis is most likely the true botanical template behind the ancient Maya k’an glyph and this finding would show the continuity of use of this medicinal plant from ancient to modern times. Vaccinium was selected for an in depth phytochemical analysis using modern metabolomic methods. Nuclear magnetic resonance (1H NMR) was used to evaluate leaf extract spectra to provide information on (1) the taxonomic identity and (2) quantities of bioactive metabolites across multiple sites. Spectra clearly differentiated leaf samples of V. angustifolium, V. boreale, V. corymbosum, V. macrocarpon, V. myrtilloides, V. myrtillus, V. ovalifolium, and V. uliginosum according to generic, subgeneric, specific, phenotypic circumscriptions. Quantification of chlorogenic acid and hyperoside were replicated with a method that is highly reproducible across multiple sites with different NMR equipment. This methodology provides an important new approach to taxonomy and quality control for plants and natural health products.

Given the expansion of multimedia technology and proliferation of moving projections on the theatre stage in the 21st century, this thesis examines how a virtual or projected character can appear to be present without a physical body on the stage. This study is grounded in the theories of effet de présence (effect of presence) as elaborated by Josette Féral, but also uses other theories to look at how productions can create such an effect for virtual characters. Specifically, this thesis examines the character’s relationship with the real, framing devices and actions of the characters. The specific examples of Rwanda 94 (Groupov), La Belle et la Bête (4D Art) and Les Aveugles (UBU CC) are used as case studies in order to focus on these techniques. Partant de l’intégration des nouvelles technologies et la prolifération des projections vidéo au sein des scènes théâtrales du 21e siècle, cette thèse examine les techniques par lesquel les personnages projeté peut sembler présent en l’absence d’un corps physique visible. Cette réflexion est basée sur l’effet de présence, concept élaboré par Josette Féral, ainsi que d’autres théories et examine comment un effet de présence est constitué pour ces personnages virtuels en considérant leur relation au réel (mimesis), les dispositifs de cadrage dans lesquels ils s’inscrivent de même que leurs actions. Cette analyse sera menée à porter de avec trois étudies de cas : Rwanda 94 (Groupov), La Belle et la Bête (4D Art) et Les Aveugles (UBU CC).

In this thesis, we present a tool that is an extension of the NAVIRE Framework and used in remote environment exploration and navigation. It is available for end users on everyday devices such as desktops and mobile devices. The tool offers the characteristic of being cross-platform and easy to use and manipulate. Cubic panoramas that are generated by the NAVIRE Framework are loaded in the tool and rendered in 3D space on the user’s device. The 3D panoramas are interactive by allowing the user to view the scene in all direction, move from one scene to another or through interaction with augmented objects. The tool is geared to be interactive in the most natural and intuitive fashion using the inputs available in the different devices of the end-user.

Understanding the impact of coastal forests on the propagation of rapidly advancing onshore tsunami bores is difficult due to complexity of this phenomenon and the large amount of parameters which must be considered. The research presented in the thesis focuses on understanding the protective effect of the coastal forest on the forces generated by the tsunami and its ability to reduce the propagation and velocity of the incoming tsunami bore. Concern for this method of protecting the coast from tsunamis is based on the effectiveness of the forest and its ability to withstand the impact forces caused by both the bore and the debris carried along by it. The devastation caused by the tsunami has been investigated in recent examples such as the 2011 Tohoku Tsunami in Japan and the Indian Ocean Tsunami which occurred in 2004. This research examines the reduction of the spatial extent of the tsunami bore inundation and runup due to the presence of the coastal forest, and attempts to quantify the impact forces induced by the tsunami bores and debris impact on the structures. This research work was performed using a numerical model based on the Smoothed Particle Hydrodynamics (SPH) method which is a single-phase three-dimensional model. The simulations performed in this study were separated into three sections. The first section focused on the reduction of the extent of the tsunami inundation and the magnitude of the bore velocity by the coastal forest. This section included the analysis of the hydrodynamic forces acting on the individual trees. The second section involved the numerical modeling of some of the physical laboratory experiments performed by researchers at the University of Ottawa, in cooperation with colleagues from the Ocean, Coastal and River Engineering Lab at the National Research Council, Ottawa, in an attempt to validate the movement and impact forces of floating driftwood on a column. The final section modeled the movement and impact of floating debris traveling through a large-scale model of a coastal forest.

Little is known about the specific cognitive impairments that may be the cause of the reported increased crash rate in individuals with early dementia. Though, it is widely accepted that attention, visuospatial and perceptual abilities are central in being able to operate a vehicle safely. This study had three objectives. The first was to clarify the neuropsychological profile, with an emphasis on attention, visuospatial and perceptual abilities, of individuals with early dementia with Lewy bodies (DLB), the next was to examine the driving performances of two groups of individuals with early dementia (i.e., early Alzheimer’s disease, AD, and early DLB) and the last was to examine the degree of association between neuropsychological impairments and driving impairments in hopes of predicting poor driving outcomes. Fifty-six participants were recruited from three groups; 20 individuals diagnosed with early AD, 15 individuals diagnosed with early DLB and 21 healthy age-matched controls. All participants were administered the following neuropsychological tests: the Mini-Mental Status Exam (MMSE), the Dementia Rating Scale (DRS-2), the Boston Naming Test (BNT), the Test of Everyday Attention (TEA), the Visual Object and Space Perception Test (VOSP) and the Useful Field of View (UFOV). Additionally, a simulated driving task was completed, with data being collected through primary measures recorded by the simulator as well as an experimenter based driving assessment using a demerit-point test. Results indicated that individuals with early DLB were found to be most impaired in their visuospatial abilities, selective and divided attention abilities, and were found to have significant cognitive fluctuations. Driving performances confirmed that drivers with early dementia were at greater risk for motor vehicle collisions (MVC) and they were found to commit a significant number of driving errors during the driving simulation. Finally, this study was able to demonstrate that in drivers with early AD, attentional impairments were the strongest predictors of driving impairment, whereas in drivers with early DLB, visuospatial impairments were indicative of driving impairment.

A harsh, cold, and icy environment is of no surprise to the conditions of a winter climate, where the wide use of de-icing salts on roads and highways allows for the initiation of chloride-induced corrosion of the reinforcement of concrete structures; a reduced service life, loss of structural integrity, visible damages, and ultimately structural failure are among the many unwanted effects of rebar corrosion. Chloride ingress into concrete has been extensively studied for the last four decades; however, most of the relevant research to date does not take into account the effects of sustained loading on chloride transport properties. Therefore, the objectives of this study were to investigate the influence of sustained compressive and tensile stresses on chloride ingress into concrete, and ultimately to understand what the effect of sustained stress is on chloride penetration depth, on chloride concentration by % weight of concrete, and on apparent diffusion coefficients by comparing results to those of unloaded control specimens. To achieve these objectives, six post-tensioned and four non-reinforced control concrete beams were constructed with different water-to-cement (w/c) ratios and completely submerged in a 4-5% de-icing salt (NaCl) solution for 12 weeks, allowing chloride transfer to be completely governed by continuous diffusion. The effects of supplementary cementing material on chloride ingress are also studied. Concrete beams were post-tensioned to induce variable sustained compressive and tensile stresses along the beam. After 12 weeks of exposure, beams were fractured at specific locations and sprayed with a 0.1N silver nitrate (AgNO3) solution to determine average penetration depths; chloride concentration profiles were obtained from potentiometric titration of grinded powder samples. Apparent chloride diffusion coefficients were then obtained from the results of spraying AgNO3 and titration, the latter by non-linear regression curve-fitting to Fick’s second law of diffusion. A good agreement between results from both methods reveals that the use of AgNO3 in field is acceptable in predicting the rate of chloride ingress in concrete sustaining stress. The chloride diffusivity for each profile, relative to that of the unstressed section, was related to the compressive and tensile stresses in the concrete section. The experimental results indicate the dependence of chloride ingress and concentration on the type and level of sustained stress. An analysis of the results to study the effects of the w/c ratio using colourimetric (silver nitrate spray) and potentiometric titration methods was also completed.

This study, patterned on Benton’s (2009) model of the four conceptions of interpretation which includes connecting visitors to resources through use of interpretive techniques, conveying mission and influencing behaviour, encouraging environmental literacy, and promoting recreational outcomes (modified from Benton’s use of tourism outcomes), took a comprehensive approach to examine the recreational and environmental outcomes of participation in interpretive programs at Gatineau Park (N = 78). The findings included significant correlations between the interpretive techniques and environmental literacy (n = 73, r = .711, p = .000), pro-environmental behavioural intentions (n = 70, r = .267, p = .025), and recreation satisfaction (n = 67, r = .419, p = .000) outcomes. There was also a significant correlation between recreation satisfaction and environmental literacy (n = 66, r = .518, p = .000). Path analysis indicated the direction of these relationships with environmental literacy directly influencing recreation satisfaction and interpretive techniques indirectly influencing recreation satisfaction through environmental literacy, revealing that environmental literacy mediated the relationship between the interpretive techniques used and recreation satisfaction.

The objective of this thesis is to analyze the kinematics of a mobile parallel robot with contribution that pertain to the singularity analysis, the optimization of geometric parameters and the optimal control to avoid singularities when navigating across singular geometric configurations. The analysis of the workspace and singularities is performed in a prescribed reference workspace regions using discretization method. Serial and parallel singularities are analytically analyzed and all possible singular configurations are presented. Kinematic conditioning index is used to determine the robot’s proximity to a singular configuration. A method for the determination of a continuous and singularity-free workspace is detailed. The geometric parameters of the system are optimized in various types of pipe-like structures with respect to a suitable singularity index, in order to avoid singularities during the navigation across elbows. The optimization problem is formulated with an objective to maximize the reachable workspace and minimize the singularities. The objective function is also subjected to constraints such as collision avoidance, singularity avoidance, workspace continuity and contact constraints imposed between the boundaries and the wheels of the robot. A parametric variation method is used as a technique to optimize the design parameters. The optimal design parameters found are normalized with respect to the width of the pipe-like structures and therefore the results are generalized to be used in the development phase of the robot. An optimal control to generate singularity-free trajectories when the robotic device has to cross a geometric singularity in a sharp 90◦ elbow is proposed. Such geometric singularity inherently leads to singularities in the Jacobian of the system, and therefore a modified device with augmented number of degrees of freedom is introduced to be able to generate non-singular trajectories.

Cisplatin (CDDP; cis-diamminedichloroplatinum) resistance presents a major impediment in the treatment of several gynecologic solid tumors, including ovarian and cervical tumors. p53, a critical regulator of cellular apoptosis, is a determinant of CDDP sensitivity. In our study, we have observed that the dysregulation of p53 regulators, checkpoint kinase 1 (Chk1) and protein phosphatase magnesium-dependent 1 (PPM1D), significantly reduced CDDP responsiveness in human cancer cells. Isogenic wt-p53 CDDP-sensitive (OV2008) and -resistant (C13*) cervical cancer cells, and isogenic wt-p53 CDDP-sensitive (A2780s) and p53 mutant resistant (A2780cp) ovarian cancer cells, along with CDDP-resistant ovarian cancer cell lines (OCC-1 and OVCAR-3, mutant p53; SKOV-3, p53 null) were used to elucidate the mechanisms of p53 regulation in human gynecologic cancer cells. We have complemented our study with a xenograft model (A2780s) and a tissue microarray of human ovarian tumors to validate our in vitro observations. We have demonstrated that CDDP differentially regulated the p53 activator Chk1 in sensitive and resistant cancer cells; it enhances Chk1 activation in sensitive but not resistant cells. This differential regulation also extended to PPM1D, whereby CDDP enhanced PPM1D content in resistant but not sensitive cells. PPM1D knockdown sensitized resistant cells to CDDP, which was associated with up-regulation of Chk1 and p53 activations, while PPM1D over-expression had the opposite effect. We have also shown that CDDP sensitivity in response to PPM1D down-regulation was p53-dependent. Moreover, CDDP promotes PPM1D nuclear localization in resistant cells and nuclear exclusion in sensitive cells and xenograft tumors. Enhanced PPM1D expression in human ovarian tumors is significantly associated with tumor aggression. Dysregulation of the oncogene Akt has been implicated in a variety of human malignancies, including ovarian cancer. We have demonstrated that Akt regulates PPM1D stability, since activated Akt over-expression in sensitive cells rescued PPM1D from CDDP-induced proteasomal degradation and Akt down-regulation in resistant cells lead to PPM1D de-stabilization and down-regulation. We have shown for the first time that PPM1D is downstream of Akt through which it can modulate CDDP sensitivity in human cancer cells. These findings extend the current knowledge on the molecular basis of CDDP resistance in gynecological cancers and may help in developing effective therapeutic strategies.