http://hdl.handle.net/11343/159 2017-06-24T01:06:32Z http://hdl.handle.net/11343/178362 The role of protease-activated receptor-2 in periodontal disease Francis, Nidhish Abstract withheld © 2017 Dr. Nidhish Francis 2017-01-01T00:00:00Z http://hdl.handle.net/11343/178361 Anxiety and stuttering: closing the research gaps Smith, Kylie Background: Adults who seek treatment for stuttering are significantly more likely to be diagnosed with social anxiety disorder than non-stuttering controls. However, it is unclear when the onset of anxiety in stuttering typically occurs, and whether there are differences between children who stutter in the general community and those who seek treatment. Aims: The aims of this thesis were to: 1. Review the research pertaining to anxiety and stuttering in children and adolescents, to identify trends and determine the timing of anxiety onset in stuttering; 2. Compare anxiety symptoms, emotional and behavioural functioning, and temperament traits in children from a community sample who (i) stutter, (ii) have recovered from stuttering, and (iii) have never stuttered; 3. Compare anxiety symptoms, and emotional and behavioural functioning, for children who stutter from: (i) a community cohort study (community stuttering cases) and; (ii) a clinical case-control study (clinical stuttering cases), and children who have never stuttered and; 4. Compare family and environmental characteristics, and social and emotional functioning, for control groups recruited to a community cohort study and clinical case-control study. Methods: For Aim 1, peer-reviewed publications investigating anxiety in preschoolers, children, and adolescents who stutter were identified using specific search terms in Medline, CINAHL and psycINFO databases. Known risk factors for anxiety in stuttering children and adolescents were identified, and the research evidence related to anxiety in this population was appraised. For Aim 2, measures of child anxiety, temperament, and emotional and behavioural functioning were completed by children and parents from a community cohort study, including (i) children who stuttered, (ii) children who had recovered from stuttering, and (iii) non-stuttering controls. Linear regression modelling compared outcomes between the three groups, controlling for a range of child, family and environmental variables. For Aims 3-4, outcomes were then compared to those from children who stutter and non-stuttering controls from a clinical case-control study. Results: Regarding Aim 1, based on a review of the literature, the age of anxiety onset in stuttering could not be reliably determined. Regarding Aims 2 - 4, all groups in the community cohort study had scores within the normal range on measures of anxiety, and emotional and behavioural functioning, with no significant differences between groups. Similarly, scores on all measures fell within the normal range for the children in the clinical case-control study. However, children who stutter from both the clinical and community studies reported higher social anxiety and internalizing symptoms compared with non-stuttering controls. As a group, the clinical stuttering cases reported higher generalised anxiety symptoms than the community stuttering cases. The controls participating in the case-control study came from a higher socioeconomic background than the other three groups. They also had lower anxiety scores than the community controls. Conclusion: While in the normal range, higher social anxiety symptoms among school-age children who stutter from clinical and community samples may mark the start of the development of social anxiety disorder in stuttering. Higher general anxiety symptoms among clinical stuttering cases compared with community stuttering cases may be a driver for seeking treatment for stuttering. Differences in socioeconomic status and anxiety among participants recruited to clinical and community stuttering studies highlights the need for understanding the nature of control groups when interpreting research findings. Further research with community samples of children who stutter is needed to further clarify risk factors for the development of social anxiety in stuttering. © 2017 Dr. Kylie Smith 2017-01-01T00:00:00Z http://hdl.handle.net/11343/177358 Optimal market thickness and market design Muir, Ellen Victoria In this thesis we primarily focus on developing tractable dynamic market models, together with applications of these models. We also address several open questions concerning the statistical properties of static market models. The original research contained in this thesis begins when we define a new distribution, called a general non-central hypergeometric distribution, which models biased sampling without replacement. We then consider a classic mechanism design market model with unit traders in which buyer valuations and seller costs are independent and, on each side of the market, identically distributed. We show that the equilibrium quantity traded has a general non-central hypergeometric distribution under a broad class of mechanisms, where the sampling bias encodes information about the distribution of buyer values relative to seller costs, strategic behaviour of market participants and rent extraction by the market intermediary. We then extend this work by developing a general approach to approximating outcomes in large markets. In particular, we show that the joint distribution of the equilibrium quantity traded and welfare is asymptotically normal, compute the parameters of the approximating normal distribution and bound the approximation rate. We then turn our attention to dynamic market models in which traders with persistent types arrive over time and focus on optimally assessing the tradeoff between the benefits of increasing market thickness and the cost of delay. We start by considering a two-period extension of the classic model of Myerson and Satterthwaite and derive the class of Bayesian optimal mechanisms. Investigating the properties of these mechanisms, we compare them to benchmark static mechanisms and find that dynamics tends to increase the convexity of the region of trade in period one. Motivated by the computational complexity of these optimal mechanisms, we consider approximate implementation in the form of a price-posting mechanism, before turning our attention to models with simpler type spaces. Finally, we consider an infinite-horizon market model in which agents have binary type spaces. Assuming that a buyer-seller pair arrives in each period and agents are privately informed about their types, we introduce notions of dynamic efficiency and optimality and construct the class of Bayesian optimal mechanisms. We demonstrate that, provided the discount factor is sufficiently large, a profit-maximising two-sided platform creates higher welfare compared to a less centralised, welfare-targeting market maker. Further, the main benefits from dynamic mechanisms are reaped by clearing markets at fixed, optimally chosen frequencies. We consider a variety of economic applications including in-house production by the designer, taxation policy and asymptotically optimal prior-free mechanisms. With minor qualifications (including a dynamic generalisation of Myerson regularity), our analysis and main results apply to more general arrival processes and type spaces. © 2017 Dr. Ellen Victoria Muir 2017-01-01T00:00:00Z http://hdl.handle.net/11343/177357 How cinema surrounds us: the psychology of psychogeography in the works of Sofia Coppola Henderson, Laura Clare Mereki The settings and spaces presented to the spectator by a film can be some of the most memorable and pleasurable elements of cinema. While the affective turn in screen theory has moved towards a consideration of an embodied spectator, there is still little consideration of how the spectator experiences filmic space. Moreover, although there is significant evidence that many elements of this interaction occur at a neurological level, few scholars have taken this into consideration. This dissertation aims to address these gaps by engaging contemporary film theory with recent areas of psychological research. By juxtaposing these two bodies of knowledge in an analogic flow, new ways of understanding how the spectator interacts with a cinematic world emerge. Taking the work of Sofia Coppola as a case study, the thesis builds on Giuliana Bruno’s account of the psychogeography of cinema, and demonstrates that the perception of filmic landscapes is a neurally embodied, intimate and intersubjective practice. The major findings presented concern the ways the perception of cinematic psychogeographies mirror, incite and operate upon the neural underpinnings of consciousness. The research also interrogates how a spectator constructs personal relationships with film spaces, how these spaces change our perception of the material world, and how this might impact on the study of film spectatorship. The personal construction of film spaces indicates a direct and neurally intimate relationship between text and spectator. This thesis tenders a possible (and currently unexplored) avenue for the study of spectatorship that reflects this relationship. © 2017 Dr. Laura Clare Mereki Henderson 2017-01-01T00:00:00Z