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Bloodstream trypanosomes initiate differentiation to procyclic forms in response to a citrate/ cis-aconitate (CCA) signal. A cell line was previously selected (“defective in differentiation-clone 1”; DiD1) that was unable to differentiate to procyclic forms (Tasker et al. (2000)). Additionally, expression profiling of this line in comparison to the parental line by macroarray hybridisation identified two differentially-expressed transcripts from an 8 gene cluster of highly homologous genes we named PAD genes (Proteins Associated with Differentiation). Members of this family show distinct expression profiles throughout the trypanosome lifecycle at both the mRNA and protein level, and are localised to the cell surface membrane of the cell. At least 1 member of the family (PAD1) shows stumpy form specific RNA and protein expression, representing the first useful molecular marker for this stage, and exhibits biochemical specificity for citrate. Additionally, another member of this family (PAD2) is upregulated in response to low temperature, a condition reported to cause hypersensitivity to CCA. Finally, RNAi mediated ablation of the PAD gene transcripts compromised the capacity of stumpy form trypanosomes to differentiate to the procyclic form in response to CCA. These combined expression, cytological, reverse-genetic and biochemical data make PAD proteins excellent candidates for recognition of the signal to initiate differentiation in response to CCA.

The mixed sand and gravel barrier beaches located on the South Island's East Coast are formed predominantly of Greywacke, eroded from the mountains, and transported via the major river systems. These barriers act as the interface between the South Pacific Ocean and the surrounding hinterland. In times of high energy coastal events, breaching is common. This thesis examines the form and function of the Waihao-Wainono barrier, a section of the coastline situated north of the Waitaki River. Breaches along this part of the barrier are frequent and several have rendered the surrounding farmland unusable for several years due to the effects of saltwater inundation. There is some concern among the local community as to exactly why the barrier breaches at certain locations and not others, making land planning and management a difficult task for farmers. Several of the local landowners believe that since the construction of the Waitaki Dam in 1935, a significant decrease in sediment size along the barrier has occurred. It is also thought that the barrier form has experienced substantial change. Through the use of physical techniques used in the field of coastal science, 17 sites along the Waihao-Wainono barrier were studied. Excavations were carried out, surface and substrate profiles recorded and sediment samples collected from the surface. sub-surface and substrate of the barrier. Analysis of the barrier form and barrier volume concluded that the past breach sites consisted of steeper lower foreshore slopes than the non-breach sites, and at two sites, the substrate was not reached. Breach areas display the greatest barrier volume of all the study sites, which is contrary to belief. In relation to the surface sediments, the majority of barrier profiles displayed the distinct mean grain size cross shore zonation, characteristic of mixed sand and gravel beaches. The best and most consistent surface sorting was also identified as being a characteristic of the breach sites. The sediment size is not shown to have drastically reduced over the thirty year sampling period as was perceived by the local community. Within the sub-surface of the barrier, the sediments displayed chaotic sizes and generally poorly sorted material. Several of the breach sites contained a distinct change in sediment size between the coarser surface layer and the finer layer located immediately below. This layering of coarse and fine sized sediments leads to differences in permeability within the barrier, which is thought to be a major factor in why these sites have breached. Resulting from these findings, a group of characteristics of breach sites was formed and several predictions made as to where the barrier may breach in the near future.

The Functions and the Ordering of Conditional `If Clauses' in English---A Genre AnalysisPrevious research studies are in agreement that the canonical order for English if conditionals is sentence-initial rather than final. However, earlier findings regarding the distribution of the ordering between initial and final if-conditionals represent only those patterns specific to the limited number of genres examined. This corpus linguistic study is based on a research approach which includes a larger sampling pool and a selection of representative genres as well as detailed statistical and content analyses. It examines the variations in the distributional patterns between initial and final if-clauses within each individual genre and across different genres. The findings of this study suggest that if-conditionals have significantly different distributional pattern across genres. In contrast to the consensus view in current literature that initial if-clause rather than final is the dominant clause order, in 3 of the genres examined in this study (Letters to the Editor, Recipes and Sports News) final if-clauses occur more frequently than initial. In addition, in 3 other genres (News Reportage, Science Fiction and Romance Fiction) these two clause types are equally distributed. This study thus identifies genre as a significant factor influencing sentential if-conditional placement.The study also argues that in addition to the expression of topic and focus discourse relations, the ordering of the conditional and consequence clauses is often used to convey specific pragmatic effects and to perform functions related to genre-specific needs, including social politeness and showing power deixis, hedging or strengthening a proposition. / Department of English

Canada’s population is aging rapidly, such that by 2031 it is estimated that one quarter of Canada’s population will be aged 65 or older (Statistics Canada December 15, 2006). It is argued that urban environments are often not adequately designed for older people and can impair their ability to live independently into their elder years (Harris 2004). Proper planning can help people age successfully in their community. This research practicum assesses three town centres within the City of Surrey to determine whether they are agefriendly based on the perceptions of residents over the age of 65. Results from the research found that areas in need of improvement included public transit, the walking environment, clustering various land uses, parks amenities, and home assistance, among other things. The practicum concludes with recommendations of areas for further study.

City design has long been recognized as predicated on power. Planners have the power to regulate the use and form of privately owned land—an enormous task. Zoning is the foundation of city planning. The caliber of cities' future development hinges on zoning. Over the last fifteen years, communities have been divesting themselves of their historic Euclidean zoning in favor of the newer concept of form-based code. However, changing an entire zoning code is an immense project that requires a massive investment of motivation, time, perseverance and money. Does changing code provide an answer to undesirable consequences of Euclidean zoning, or are the claims of form-based code advocates correct and their code the panacea for everything wrong with planning and development? This is a sweeping question and one that is asked in hundreds of planning offices by planners, urban designers, politicians and their communities. The primary question is why and how communities change from conventional Euclidean zoning to form-based code. This research examines the state of practice and the impact of form-based code on zoning. Issues critical to an examination of the theory and practice aspects of this investigation includes key questions: What motivates change? What difference does it make? Who are the primary motivators for change? What is the comparative analysis and the basis for change and the impact of form-based code? Two protocols, including online surveys of planning practitioners and case studies of Cincinnati, Denver and Miami, are used to investigate the intended, and often unintended, outcomes and consequences that emerge with a zoning change within an established community.

This thesis describes research into the development of a Computer Aided Design (CAD) tool that uses a Genetic Algorithm (GA) to generate and evolve original design concepts through human interaction. CAD technologies are firmly established in the later stages of design, and include many applications of Evolutionary Algorithms (EAs). The use of EAs as generative and search tools for conceptual design is less evident in fields other than abstract art, architecture and styling. This research gains its originality in aiming to assist designers early in the design process, by creating and evolving aesthetically interesting forms (objects). The integration of GA software with a solid modelling system has enabled the development of a prototype `Evolutionary Form Design' (EFD) system. Objects are defined using a genetic data structure and constructed from various geometric primitives and combinations of Boolean operators. The primitives interact in ways that are not easily predicted, often creating novel shapes that are unlikely to have been discovered through conventional means. Edge blending further adds to objects' complexity and visual appeal. Populations of objects are subjected to a `selective breeding' programme, directed through the user's allocation of scores, and may also be guided by simple geometric targets. These factors determine which objects are `fittest' and most likely to parent a new, hopefully improved generation of objects. The challenge has been to turn the concept into a genuinely useful tool, ensuring that desirable features are reproduced in subsequent populations. The key to achieving this is the way objects are recombined during reproduction. Work has included developing 4 novel routine for grouping the individual primitives that form objects using a Teamforming algorithm. Innovative, aesthetically interesting forms can be evolved intuitively and efficiently, providing inspiration and the initial models for original design concepts. Examples are given where the system'is used by undergraduates to generate seating designs, and by the author, to create virtual sculptures and a range of consumer product concepts.

Bridge scour is the loss of soil by erosion due to water flowing around bridge supports. Scour has been the number one cause of bridge collapse in the United States with an average rate of 22 bridges collapsing each year. This dissertation addresses three topics related to bridge scour. First, three sets of databases are used to quantify the statistical parameters associated with the scatter between the predicted and measured scour depth as well as the probability that a deterministically predicted scour depth will be exceeded. The analysis results from these databases will also be used to provide the bias factors in the scour depth predictions in practice. In the second part of the dissertation, these statistical parameters are used to develop a reliability-based Load and Resistance Factor Design (LRFD) for shallow and deep foundations subjected to scour. The goal is to provide a design procedure for the bridge foundations, where the reliability of the foundation is the same with or without scour. For shallow foundations, the key of the design issue is the location of the foundation depth and the probability that the scour depth will exceed the foundation depth. Therefore, for shallow foundations, the proposed LRFD calibration is based on the probability of exceedance of the predicted scour depth. However for deep foundations, the key of the design issue is the resistance factor associated with the axial capacity of a pile. Hence, the proposed LRFD calibration for deep foundations is based on a reliability analysis using First-Order Reliability Method (FORM). The dissertation is broadened in the third part by analyzing he risk associated with bridge scour, where the risk is defined as the probability of failure times the value of the consequences. In the third part, the risk associated with bridge scour is compared to risks associated with other engineering structures as well. Target values of acceptable risk are recommended as part of the conclusions. The outcome of the research will modify the current “AASHTO LRFD Bridge Design Specifications” developed by the American Association of State Highway and Transportation Officials (AASHTO) and help the practitioners design foundations of bridges over rivers for a uniform probability of failure in the case of scour. The risk of bridge scour is also quantified in the dissertation, and compared with common societal risks and civil engineering risks. It will help engineers understand the risk level associated with bridge scour.

This thesis presents evidence that income polarization is accompanied by increasing social-spatial disparities between areas of the city that were developed in different societal contexts, with different planning approaches, and that have different land use and transportation dynamics. An analysis of the social structure of the Toronto Metropolitan Area finds indications of widespread gentrification in the inner city, socioeconomic decline in the postwar suburbs, and sustained household affluence in the ever expanding outermost suburbs of the metropolitan area. It is argued that, as a political and social endeavor that is embedded in broader development regimes, urban planning influences social-spatial polarization to the extent that it influences urban form.

This study examines gender typing of industrial products in the activity of industrial design. Thus firstly, the meaning of gender, related theories and gender stereotypes have been reviewed through the literature survey in order to pinpoint the stereotypical attributes assigned to men and women through society and culture. Secondly, the effect of the stereotypical gender attributes on the act of possessing products have been examined. In return, a literature survey on the cognitive aspects of design has been conducted in order to question whether these gender attributes might have a similar impact on the design activity. The findings of the literature survey pointed towards categorical information processing theories as an appropriate tool to gender type products and also as a tool to measure the gender qualities of a product. To test the applicability of the methodology of categorization a study has been conducted with industrial designers and industrial design students in which the students were asked to design gender typed products and industrial designers were asked to rate their perceptions of genderedness of the designs. The test revealed the existence of a mental library consisting of categorized images corresponding to stereotypical gender attributes in the individuals, thus preparing the grounds for the use of this process in the industrial design activity.