12,496 results for Doctoral

  • Spiritual vegetarianism: identity in everyday life of Thai non-traditional religious cult members

    Makboon, Boonyalakha

    Doctoral thesis
    Auckland University of Technology

    This thesis examines how the participants who are Thai and vegetarians integrate vegetarianism into their lives, and how they produce and maintain their vegetarian identity element. This video-ethnographic study was conducted in Thailand over the course of five months, with particular attention to three participants who are members of non-traditional religious cults in Thailand, where vegetarianism is a normal practice. Utilizing multimodal (inter)action analysis (Norris, 2004, 2011a), I conducted a micro analysis by teasing apart the participants’ real-time interactions, investigating how different modes come to play together to make certain actions possible. The analysis also incorporates other data from observational notes, sociolinguistic interviews and photographs. I discovered that the participants produced a spiritual vegetarian identity element in accordance with their religious belief. The participants produced multiple identity elements, including but not limited to their spiritual vegetarian identity element, at differentiated levels of the participants’ attention/awareness. At the time of the study, my participants did not continuously produce their spiritual vegetarian identity element, and thus a spiritual vegetarian identity was not their most salient identity element. However, I found that vegetarianism plays a significant role in the participants’ lives as they always produced their spiritual vegetarian identity element in connection with other identity elements. This results from the fact that these identity elements were developed within a religious context which was embedded in the historical body (Nishida, 1985) of the participants. Religion has exerted a substantial influence on many aspects of their lives and their resulting identity elements.

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  • Performance analysis of fielding and wicket-keeping in cricket to inform strength and conditioning practice

    MacDonald, Danielle Catherine

    Doctoral thesis
    Auckland University of Technology

    The purpose of this thesis was to contribute to the scientific understanding of the performance demands of One Day International (ODI) fielding and wicket-keeping, and to provide recommendations for improving athlete performance, assessment and coach education. Two comprehensive literature reviews of the physical, technical, physiological and tactical components of fielding and wicket-keeping were conducted. Given the gaps identified in the literature reviews, an online mixed method survey of cricket players, coaches and trainers was designed to investigate the performance requirements of the wicket-keeper, close, inner and outer circle fielders. Players and coaches rated agility the most important physical attribute for the wicket-keeper (4.7/5), close fielders (4.6/5), and inner circle fielders (4.8/5). Speed (4.8/5) and agility (4.6/5) were rated most important for outer circle fielders. Coaches raised the issue of the lack of a cricket specific agility test. An emerging theme for all categories was the importance of the mental aspects of the game such as positive attitude and concentration, particularly for the wicket-keeper. To validate the use of video footage for performance analysis a comparison was made between televised and purposefully collected video for event coding. The variables of interest were derived from the literature reviews and corroborated by the survey. The ICC for intra-coder reliability for all but two variables was between 0.88 and 1.00 the exceptions were lateral footwork (step 0.83 and shuffle 0.55) likely due to the subjectivity of defining footwork patterns. The televised footage under-reported the frequency of wicket-keeping activity (≈4.5%), except for lateral footwork, which was under-reported by the purposefully collected video (≈13.5%) due to the movement being perpendicular to the camera view. Even though fielding activity was under-reported (≈4.25) by televised footage, this footage was deemed to be most appropriate, as the collected footage resulted in a field of view that made the finer details of fielding difficult to distinguish. Performance analysis studies on fielding and wicket-keeping were carried out using televised footage from the 2011 ODI World Cup. The majority of the wicket-keepers movements were lateral (75%); primarily repetitive low intensity movements interspersed with explosive movements such as diving and jumping. Wicket-keeping glove-work skills (69%) were the most performed skill activity, the quality of which was quantified using a catching efficiency measure (93%). Close, inner and outer circle fielders had variable involvement in fielding activities. Close fielders were involved in 20% of the fielding activity, the bowler the most (58%) involved. The inner circle fielders were involved in 50% of fielding contacts; of whom cover was the position most involved (21%) Inner circle fielders had to display the greatest range of skills within the field, such as catching from different heights, varied throwing and ground fielding techniques. Outer circle fielders were involved with 30% of the fielding contacts; the outer circle position most involved was long on (14%). Long sprints were the hallmark of outer circle fielding, following the sprint, they often had to perform explosive movements such as a dive or a jump to field the ball; they rarely had the opportunity to stop and position themselves to perform their skill. Additionally, catching (75%,89%, 85%) throwing (0%,12%, 33%) and overall fielding performance (89%,98%,99% ) were quantified using efficiency calculations for close, inner and outer circle fielders respectively. The findings of the literature reviews and studies expanded upon the only previous study to quantify fielding performance, and informed the development of performance profiles of fielding and wicket-keeping. Subsequently recommendations for assessment, training and coaching have been made, which will be integrated into New Zealand Cricket resources. Most notable are suggestions for improving the existing skill and physical testing batteries

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  • The cultural transmission of cookery knowledge : from seventeenth century Britain to twentieth century New Zealand

    Inglis, Raelene (2007)

    Doctoral thesis
    University of Otago

    xv, 354 leaves :ill., map ; 30 cm. Includes bibliographical references. University of Otago department: Anthropology.

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  • Feeding the lambs : the influence of Sunday Schools in the socialization of children in Otago and Southland, 1848-1901

    Keen, David Stuart (1999)

    Doctoral thesis
    University of Otago

    xiv, 250 leaves :ill. ; 30 cm. Includes bibliographical references.

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  • 'The danger of vertigo' : an evaluation and critique of Theōsis in the theology of Thomas Forsyth Torrance

    Habets, Michael (2006)

    Doctoral thesis
    University of Otago

    vii, 387 leaves ; 30 cm. Includes bibliographical references. University of Otago department: Theology and Religious Studies

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  • ICTs and Rural Development in South India: Problematising Empowerment, Social Capital and Volunteering

    Chatbar, Rakhee (2015)

    Doctoral thesis
    University of Otago

    This thesis examines the deployment of Information and Communication Technologies for Development (ICT4D) in rural India. It seeks to contribute to scholarly discussions in the field of ICT4D by examining one particular project, the M. S. Swaminathan Research Foundation’s Village Knowledge Centres (VKCs) and the Village Resource Centres (VRCs) initiative in rural South India. Drawing from substantive field research conducted in the state of Tamil Nadu and the Union Territory of Pondicherry, this thesis examines the three key developmental outcomes of the VKCs initiative — empowerment, social capital, and volunteering. The thesis argues that the VKCs initiative has not successfully met the key development objectives as the opportunities offered are not transformative and do not alter existing structural conditions. This is because the micro-contextual variations within and across rural communities are not adequately integrated into the design and implementation of the project. The thesis also argues that the VKCs initiative in rural India is significantly impacted by larger global and national structures. A more robust engagement by the NGO that considers the inter-connectedness of institutional, social and cultural structures and micro-contexts is central to harness the potential of ICTs to deliver development objectives. In undertaking this study, the thesis makes the following research contributions. First, the thesis responds to scholarly demand for empirically based engagements as a key means to ascertain the potential of ICTs for development. Secondly, the thesis broadens the theoretical and empirical understanding of empowerment, social capital and volunteering in ICT4D. Finally, the thesis proposes a number of practical recommendations for policy makers. The thesis aims to contribute to research in ICT4D, studies on rural development in India, and to future strategies for incorporating ICTs more effectively in development planning and practice.

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  • Generation and structural characterisation of transient gaseous species.

    Atkinson, Sandra Jane (2015)

    Doctoral thesis
    University of Canterbury Library

    Gas electron diffraction (GED) is a technique that has been developed to study the molecular structure of species in the gas phase. This thesis focuses on the reconstruction of the Canterbury GED apparatus (moved from Edinburgh, UK) and the requirements for modifying the apparatus to incorporate a mass spectrometer (MS) so diffraction and MS data can be obtained within a single experiment. The combined GED-MS system has been identified in previous work in the Masters group as a necessary development for studying the structure of short-lived species generated in situ. This is particularly true for the study of ketene, which as shown in this thesis, can be generated from several precursors as part of a multiple product pyrolysis system. While GED data for ketene generated from acetic anhydride has been refined, the species formed from the pyrolysis of Meldrum’s acid were determined to be too difficult to deconvolute without additional experimental data from MS. A computational study of possible ketene derivatives that could be studied with a GED-MS apparatus is also presented. Lastly, this thesis details a structural study of the gas-phase structures of tris(chloromethyl)amine and a family of substituted disilane systems which have been determined in the gas phase for the first time. A comprehensive GED, Raman spectroscopy and ab initio study have been undertaken for tris(chloromethyl)amine [N(CH2Cl)3] which is shown to have a different structure in the solid and gas phase. Further work in the form of a molecular dynamics investigation has been identified as necessary to describe the low amplitude motion of one of the CH2Cl groups in the gas phase to allow for the GED refinement to be completed. The work on the substituted disilane systems X3SiSiXMe2 (X = F, Cl, Br, I) and X3SiSiMe3 (X = H, F, Cl, Br) demonstrates the effect of increased halogen substitution on the electronic effects of the disilanes, and the effect that the methyl groups have as larger halogens increase the steric bulk of the system.  

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  • Preparation of monolayer tethers via reduction of aryldiazonium salts.

    Lee, Lita (2015)

    Doctoral thesis
    University of Canterbury Library

    This thesis describes the preparation of surface-attached monolayer tethers from electroreduction of aryldiazonium ions using a protection-deprotection strategy. Monolayers of ethynylphenyl, carboxyphenyl, aminophenyl and aminomethylphenyl were prepared. Glassy carbon (GC) and pyrolysed photoresist film (PPF) surfaces were modified electrochemically and characterised by redox probe voltammetry. The monolayer tethers were coupled with electro-active ferrocenyl (Fc) and nitrophenyl (NP) groups for the indirect electrochemical estimation of the surface concentration. Film thickness measurement was carried out using an atomic force microscopy (AFM) depth profiling technique. The surface concentration and film thickness measurement results were consistent with the formation of monolayer films after removal of the protecting groups. Preparation of mixed monolayers was studied using three different modification strategies: i) grafting from a solution containing two different protected aryldiazonium ions, ii) sequential grafting of two different protected aryldiazonium ions, and iii) grafting of protected aryldiazonium ions followed by removal of the protecting group and reaction of an amine or carboxylic acid derivative directly with the GC surface. The composition of the mixed layer prepared using the first method is difficult to control, whereas the possibility of multilayer formation cannot be discounted using the second method. Multilayer formation is unlikely using the third method. The electrocatalysis of oxygen reduction at mixed monolayer films was investigated briefly. The origin of the two reduction peaks frequently observed for electroreduction of aryldiazonium ions at carbon surfaces was studied. Electroreduction was carried out at GC and HOPG surfaces. The reduction peak at the more positive potential is surface sensitive, while the peak at the more negative potential is not. However, both reduction peaks lead to deposition of films and it is tentatively proposed that the more positive peak corresponds to reduction at a ‘clean’ GC electrode, and the more negative peak corresponds to reduction at the already grafted layer.

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  • Analysis, development and management of glucose-insulin regulatory system for out of hospital cardiac arrest (ohca) patients, treated with hypothermia.

    Sah Pri, Azurahisham (2015)

    Doctoral thesis
    University of Canterbury Library

    Hyperglycaemia is prevalent in critical care and increases the risks of further complications and mortality. Glycaemic control has shown benefits in reducing mortality. However, due in parts to excessive metabolic variability, many studies have found it difficult to reproduce these results. Out-of-Hospital Cardiac Arrest (OHCA) patients have low survival rates and often experience hyperglycaemia. However, these patients belongs to one group who has shown benefit from accurate glycaemic control (AGC), but can be highly insulin resistant and variable, particularly on the first two days of stay. Hypothermia is often used to treat post-cardiac arrest patients or out of hospital cardiac arrest (OHCA) and these same patients often simultaneously receive insulin. In general, it leads to a lowering of metabolic rate that induces changes in energy metabolism. However, its impact on metabolism and insulin resistance in critical illness is unknown, although one of the adverse events associated with hypothermic therapy is a decrease in insulin sensitivity and insulin secretion. However, this decrease may not be notable in the cohort that is already highly resistant and variable. Hence, understanding metabolic evolution and variability would enable safer and more accurate glycaemic control using insulin in this cohort. OHCA patients were undergone preliminary analysis during cool and warm, which includes insulin sensitivity (SI), blood glucose (BG), and exogenous insulin and dextrose. Patients were analysed based on overall cohort, sub-cohorts, and 6 and 12 hour time block. Generally, the results show that OHCA patients had very low metabolic activity during cool period but significantly increased over time. In contrast, BG is higher during cool period and decreased over time. The analysis is equally important as the controller development since it provides scientific evidence and understanding of patients’ physiology and metabolic evolution especially during cool and warm. Model-based methods can deliver control that is patient-specific and adaptive to handle highly dynamic patients. A physiological ICING-2 model of the glucose-insulin regulatory system is presented in this thesis. This model has three compartments for glucose utilisation, effective interstitial insulin and its transport, and insulin kinetics in blood plasma, with emphasis on clinical applicability. The predictive control for the model is driven by the patient-specific and time-varying insulin sensitivity parameter. A novel integral-based parameter identification enables fast and accurate real-time model adaptation to individual patients and patient condition. Stochastic models and time-series methods for forecasting future insulin sensitivity are presented in this thesis. These methods can deliver probability intervals to support clinical control interventions. The risk of adverse glycaemic outcomes given observed variability from cohort-specific and patient-specific forecasting methods can be quantified to inform clinical staff. Hypoglycaemia can thus be further avoided with the probability interval guided intervention assessments. Simulation studies of STAR-OHCA control trials on ‘virtual patients’ derived from retrospective clinical data provided a framework to optimise control protocol design in-silico. Comparisons with retrospective control showed substantial improvements in glycaemia within the target 4 - 7 mmol/L range by optimising the infusions of insulin. The simulation environment allowed experimentation with controller parameters to arrive at a protocol that operates within the constraints found earlier during patient analysis. Overall, the research presented takes model-based OHCA glycaemic control from concept to proof-of-concept virtual trials. The thesis employs the full range of models, tools and methods to optimise the protocol design and problem solution.

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  • Creating New Zealand: Pākehā constructions of national identity in New Zealand literary anthologies

    Wild, Susan (2015)

    Doctoral thesis
    Victoria University of Wellington

    The desire to construct a sense of home and the need to belong are basic to human society, and to the processes of its cultural production. Since the beginning of New Zealand’s European colonial settlement, the determination to create and reflect a separate and distinctive collective identity for the country’s Pākehā population has been the primary focus of much local creative and critical literature. Most literary histories, like those of Patrick Evans (1990) and Terry Sturm (1991), have followed the narrative of progression – established initially in E.H. McCormick’s Letters and Art in New Zealand (1940) – away from colonial dependency through delineated stages from provincial and cultural nationalist phases to the achievement of a bicultural and multicultural consensus in a globalized, international context. This thesis questions the progressivist assumption which often informs that narrative, arguing instead that, while change and progress have been evident in the development of local notions of identity in the country’s writing over time, there is also a pattern of recurrent concerns about national identity that remained unresolved at the end of the last century. This complex and nuanced picture is disclosed in particular in the uncertain and shifting nature of New Zealand’s relationship with Australia, its response towards expatriates, a continuing concern with the nature of the ‘reality’ of ‘New Zealandness’, and the ambivalence of its sense of identity and place within a broader international context. New Zealand’s national anthologies of verse and short fiction produced over the twentieth century, and their reception in the critical literature that they generated, are taken in the thesis as forming a microcosmic representation of the major concerns that underlie the discourse of national identity formation in this country. I present an analysis of the canonical literary anthologies, in particular those of verse, and of a wide range of critical work focused on responses to the historical development of local literature. From this, I develop the argument that a dual, interlinked pattern, both of progress and of reversion to early concerns and uncertainties, is evident. The thesis is structured into six chapters: an introductory chapter outlines the national and international historical contexts within which the literary contestation of New Zealand identity has developed; the second outlines the contribution of influential literary anthologies to the construction of various concepts of New Zealandness; three chapters then address particular thematic concerns identified as recurring tropes within the primary and secondary literature focused on the discourse of national identity – the ‘problem’ of the expatriate writer, the search for ‘reality’ and ‘authenticity’ in the portrayal of local experience, and New Zealand’s literary response towards Australia; and the Conclusion, which summarizes the argument presented in the thesis and provides an assessment of its major findings. A Bibliography of the works cited in the text is appended at the end of the thesis.

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  • Tricksters, technology and spirit: practising place in Aotearoa-New Zealand

    Buxton, Maggie

    Doctoral thesis
    Auckland University of Technology

    Place is a tricky concept. On the surface it seems a relatively simple notion, yet underneath there are layers of contested meanings. At the same time, places face ‘wicked’ problems – issues difficult to solve by traditional methods and approaches. For these reasons there is a call from across disciplines, for flexibility and creativity in place research. This thesis weaves together technology, art, spirituality and science to create a place practice inspired by tricksters. Tricksters appear in the narratives of most cultures as liminal, paradoxical and indeterminate figures. In this research they have new relevance at a time when the boundaries of life, including the lines between sacred and profane, are no longer clearly defined. They are an inspiration for a new form of place practice which creatively weaves together ubiquitous technologies, indigenous and speculative ontologies, and integral research methodologies. The proposition is that geo-locative mobile technologies can support the work of those who work with spiritual sites, and also support the spirit or spirits of those places, when used within a trickster-inspired place practice. What are the opportunities and issues that arise from this approach? Geo-locative mobile technologies augment physical spaces with digital content and can act as mediators between the self, the physical world, digital worlds and other worlds beyond. Technology is not usually associated with spirit. However, in this research technology paradoxically plays a role in supporting the spirit of place and contributes to a progressive understanding of that term. The place practice that informed this study was situated around three spiritually significant sites: a cemetery, a marae and a public park. Within each case study, a bricolage of inter-, intra-, and transpersonal data collection methods was enacted. Integral philosophies and trickster traits combined to create the unique methodology. This research joins traditionally separate discourses: spirit of place, tricksters, and geo-locative mobile technology. It addresses the need for more creative ways of working in and with place, and raises legal, moral, cultural, and political issues in the use of mobile technologies in indigenous and/or sensitive contexts. Findings demonstrate that mobile technologies can shift perceptions of self and place, make institutional knowledge more accessible, and build connections in the third space where cultures, histories, peoples and realities meet. In these ways the practice supports the spirit of place.

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  • The son enthroned in conflict : a socio-rhetorical interpretation of John 5.17-23

    Huie-Jolly, Mary R (1994)

    Doctoral thesis
    University of Otago

    xviii, 333 leaves ; 30 cm. Includes bibliographical references. University of Otago department: Theology

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  • Actions of attention, and attention to action: investigating the relationship between visual attention, episodic representation, and language

    Webb, Andrew (2015)

    Doctoral thesis
    University of Otago

    Cognitive representations of episodes are likely to play an important role in the neural mechanisms representing the syntactic and semantic structure of natural language sentences. However, there is little consensus on how observed episodes are represented in the brain, and how those episode representations can be transformed to and from corresponding sentence descriptions. This work investigates the theory that there is a direct structural relationship between the representation of episodes and sentences describing those episodes, and that the underlying mechanism which informs the representation of an episode is based upon the sequence of sensorimotor actions involved in observing that episode. This gives rise to two predictions: firstly that there is a canonical sequence of sensorimotor actions involved in observing actions, and secondly, that changing that sequence leads to systematic changes in descriptions of those actions. Experimental results confirm that there is a strong default sensorimotor sequence involved in the observation of a range of transitive actions. However, in part due to the robustness of the default sensorimotor sequence, the second prediction was not confirmed.

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  • Taxonomy and phylogeny of industrial solvent-producing clostridia

    Keis, Stefanie (1996)

    Doctoral thesis
    University of Otago

    xii, 314 leaves :ill. (some col.) ; 30 cm. Includes bibliographical references. "June 1996". Includes previously published material by the author. University of Otago department: Microbiology.

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  • Dr Edward Shortland and the politics of ethnography

    Lousberg, Marjan Marie (2007)

    Doctoral thesis
    University of Otago

    xi, 321 leaves :col. port., map ; 30 cm. Includes bibliographical references. University of Otago department: History.

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  • Power Modelling in Multicore Computing

    Mair, Jason (2015)

    Doctoral thesis
    University of Otago

    Power consumption has long been a concern for portable consumer electronics, but has recently become an increasing concern for larger, power-hungry systems such as servers and clusters. This concern has arisen from the associated financial cost and environmental impact, where the cost of powering and cooling a large-scale system deployment can be on the order of millions of dollars a year. Such a substantial power consumption additionally contributes significant levels of greenhouse gas emissions. Therefore, software-based power management policies have been used to more effectively manage a system’s power consumption. However, managing power consumption requires fine-grained power values for evaluating the run-time tradeoff between power and performance. Despite hardware power meters providing a convenient and accurate source of power values, they are incapable of providing the fine-grained, per-application power measurements required in power management. To meet this challenge, this thesis proposes a novel power modelling method called W-Classifier. In this method, a parameterised micro-benchmark is designed to reproduce a selection of representative, synthetic workloads for quantifying the relationship between key performance events and the corresponding power values. Using the micro-benchmark enables W-Classifier to be application independent, which is a novel feature of the method. To improve accuracy, W-Classifier uses run-time workload classification and derives a collection of workload-specific linear functions for power estimation, which is another novel feature for power modelling. To further improve accuracy, W-Classifier addresses a number of common misconceptions in power modelling, which were found to impact both modelling accuracy and evaluation. These misconceptions have arisen from differences in the experimental setup and configuration, such as, execution time, handling of thermal effects and performance event selection. These differences can influence the perceived modelling accuracy, resulting in potentially misleading or erroneous conclusions if sufficient care is not taken. As a result, W-Classifier has adopted a number of additional steps to ensure good modelling practices, which were not available in previous work. In addition to improving modelling accuracy, the workload classification used in W-Classifier can be leveraged by power management policies to provide execution context to the power values. The workload context enables more informed power policies to be implemented, improving the balance between power and performance in achieving effective power management. According to experimental results, the modelling accuracy of W-Classifier is significantly better than previous multi-variable modelling techniques due to a collection of workload-specific power models derived through run-time workload classification. Therefore, W-Classifier can accurately estimate power consumption for a broader range of application workloads, where a separate power model can be used for each distinct workload.

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  • Troubling plagiarism: University students' understandings of plagiarism

    Adam, Lee Ann (2015)

    Doctoral thesis
    University of Otago

    In this thesis, I report on a doctoral study that examined undergraduate university students’ understandings of plagiarism. The thesis addresses a gap in the existing plagiarism research since much of the literature on students’ understandings of plagiarism to date has focused on institutional or staff reports. Although there is a growing body of research reporting on students’ perspectives of plagiarism, there is a paucity of in-depth qualitative studies in this area. The theoretical framework for this study was informed by social constructionist, poststructuralist, and academic literacies perspectives. These informed my research methodology, including my close attention to students’ articulated understandings of plagiarism in relation to broader institutional discourses. Methodologically, the study involved interviews with 21 students drawn from first year lectures at the University of Otago, Aotearoa New Zealand. The students represented a variety of age ranges and levels of university study. The interviews focused on the students’ understandings of plagiarism, as well as their views on learning, assessment, and what constitutes a university education. I used discourse analysis to ‘read’ the students’ responses alongside the plagiarism discourses that appeared in University policy. The thesis findings identify four main discourses that emerged in the students’ comments about plagiarism: ethico-legal discourses, where students used language reflecting a view of plagiarism as a moral or legal issue; fairness discourses, where students positioned plagiarism policy and practices as either fair or not fair; confusion discourses, where students expressed confusion about plagiarism policy and/or practices; and learning discourses, where students spoke about plagiarism as either inhibiting learning or indicating that students had not learned. These discourses were reflective of University policy that positioned plagiarism as a form of dishonesty irrespective of whether or not it was intentional. When asked to reflect on learning, assessment, and the purpose of a university education, most of the students drew heavily on employment discourses where they described universities as places in which to prepare for future employment. From an employment viewpoint, plagiarism policy and practices seemed irrelevant to most students. The findings of this research challenge the way in which plagiarism is framed at the University of Otago. Currently, plagiarism is conceptualised as a textual feature within the finished product of a student’s assignment, and both intentional and unintentional plagiarism are treated as academic dishonesty. I argue that in order to support students’ learning, unintentional plagiarism should be positioned within academic writing. Furthermore, students’ writing should be viewed as a process rather than as a product, and students should be scaffolded in their development as academic writers. I further argue that, because of the dominant ethico-legal discourses surrounding the term ‘plagiarism’, we instead use the term ‘matching text’. This would remove the implication of dishonesty, and allow for an educative response to incidences of unintentional plagiarism.

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  • Spectroscopy of Donor-Acceptor Compounds

    van der Salm , Holly (2015)

    Doctoral thesis
    University of Otago

    A number of donor-acceptor compounds have been investigated using a range of spectroscopic and computational techniques. Donor-acceptor compounds are widely used in molecular electronics applications, and it is of interest to investigate how their properties can be manipulated and probed. Ground state properties are characterised with Fourier Transform (FT) - Raman spectroscopy, which is also used to verify density functional theory calculations. The initially formed excited state (Franck-Condon state) is characterised with electronic absorption and resonance Raman spectroscopy. Transient absorption spectroscopy tends to probe the longest-lived excited state, while time-resolved infrared spectroscopy can probe intermediate states and kinetic processes as the time between pump and probe is varied. Experimental techniques are complemented by the use of density functional theory (DFT) calculations. A series of complexes containing dimethyl or diphenyl amine- substituted dipyrido[3,2-a:2',3'-c]phenazine (dppz) in which the ancillary ligand at the metal centre was varied were studied. The properties of these ligands and complexes were found to be dominated by a strong intra-ligand charge transfer (ILCT) transition from the amine to dppz, with little contribution from typical low-energy metal-to-ligand charge transfer (MLCT) transitions for complexes. Protonation shifted this ILCT transition to the near-IR; this was characterised with resonance Raman spectroscopy and time-dependent DFT (TD-DFT) calculations. Based on this study, amine-substituted dppz systems were altered in various ways in order to manipulate this ILCT transition. The effect of changing the distance between the amine donor and the dppz acceptor was investigated; this was found to influence the energy of the ILCT transition, the relative intensity of vibrational modes associated with different parts of the molecule, and the excited state lifetime, but the ILCT character appeared to be retained. The effect of the angle between the donor and acceptor units for dppz was altered in various ways. Increasing the donor-acceptor angle was found to increase the energy and decrease the intensity of the ILCT transition, and increase the intensity of an MLCT transition for Re(I) complexes. Experimental and calculated non-resonant Raman cross sections also decreased as donor-acceptor angle was increased. The effect of changing the bridge type between donor and acceptor from conducting thiophene to more insulating triazole was investigated. This increased the energy of the lowest electronic transition, and reduced the degree of ILCT in this transition, with behaviour tending towards more typical dppz as the linker became more insulating. The properties of the ligand 5,6,11,12,17,18 - hexaazatrinaphthalene (HATN) substituted with electron-donating sulfur groups were investigated. The mono-, bi- and tri-Re(CO)3Cl complexes of this ligand showed broad and intense visible absorption, which TD-DFT calculations suggested involved mixed MLCT/ILCT transitions. Resonance Raman spectroscopy was consistent with this, and time-resolved infrared (TRIR) spectroscopy provided evidence for a mixed MLCT/ILCT excited state. Finally, a series of donor-acceptor compounds that are used in dye-sensitised solar cells are discussed, in order to try and understand what makes some more efficient than others. The first series were zinc porphyrin -based with carbazole -thiophene chains, which increased their visible absorption. The second series were organic dyes, also using a carbazole donor and thiophene chain, but for these compounds the reason for differences in solar cell performance could not be established with the techniques used.

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  • The experiences of Korean immigrants settling in New Zealand: a process of regaining control

    Kim, Hagyun

    Doctoral thesis
    Auckland University of Technology

    The success of all immigrants is significant to the harmony of New Zealand society since the government’s goal is to build an inclusive society. For many Korean immigrants, however, settling in an unfamiliar environment potentially disrupts familiar routines, with deleterious effects on almost all aspects of their well-being. Despite Koreans being the fourth largest group of Asian immigrants, their experiences of settling in this country have been unheard. The purpose of this study is to listen to the voices of Korean immigrants and provide information to the receiving society that will assist with developing ways to make a Korean presence part of the cultural diversity in society. This qualitative, grounded theory study included semi-structured interviews with 25 adult Korean immigrants living in the North Island of New Zealand. Theoretical sampling was used to collect data, which were analysed using methods of constant comparative analysis, conditional matrix and memoing. Through three stages of coding, data were fractured, conceptualised, and integrated to form a substantive grounded theory which has been named; A Process of Regaining Control: A Journey of Valuing Self. Upon arrival, participants confronted circumstances that made realising the anticipated benefits of immigration difficult. They experienced a loss of control in performing previously valued activities. Language barriers and limited social networks, compounded by prejudiced social reception, were associated with their decreased involvement outside the home, leading to fewer options for acquiring knowledge necessary to function autonomously in their new environment. In response, participants worked on Regaining Control by exercising choices over what they do through opting for enacting ‘Korean Ways’ or ‘New Zealand Ways’. They initially sought a culturally familiar environment in which they engaged in activities that involved drawing on previous knowledge and skills. Continuing with accustomed activities utilising ethnic resources provided a pathway to learning about their new surroundings and thus increasing their feeling of mastery in a new country. This experience strengthened participants’ readiness to engage in activities reflective of New Zealand society. The significance of this study is that it discovers that Valuing Self is what the participants wish to accomplish, beyond the scope of mastery in a new environment. Participants continually search for a place whereby they can be accepted and valued as members of society. However, this study reveals that prejudice and discrimination towards immigrants set constraints on engagement in occupations of meaning and choices. Immigrants face socio-environmental restriction when they continue with necessary or meaningful activities, even when they have the ability to execute a particular activity. This finding makes it clear that occupation is inseparable from the societal factors in which it occurs. Further research is necessary to explore societal contexts to enrich knowledge of human occupation and how immigrants’ full participation in civic society can be promoted. Specifically, it is recommended that researchers examine what makes Korean immigrants feel valued as members of society, from the participants’ point of view, in order to assist with the development of the settlement support policy and services that best facilitates their journeys of Valuing Self in New Zealand.

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  • Predation risk and the evolution of odours in island birds

    Thierry, Aude (2014)

    Doctoral thesis
    University of Canterbury Library

    It is only recently that studies have explored the use of olfaction in birds. Birds are now known to use odour cues for navigation, and locating food. Odours produced by the birds themselves can also function in nest recognition and even mate choice. The odours of most birds stem from the preen wax produced by the uropygial or preen gland. The wax is comprised of a complex mixture of esters and volatiles, and is known to vary in some species with age, sex, season, or environmental conditions. Its function has been associated with feather maintenance, but it may also play a role in sexual selection and chemical communication. In this thesis, I used the preen gland and its preen wax to perform comparative studies on the evolution of odours between island birds and their continental relatives. I used the birds of the Oceania region as a model system, where most passerines originated from continental Australia but have colonised numerous surrounding islands such as New Zealand and New Caledonia. As islands generally lack mammalian predators, and have less parasites and less interspecific competition than continents, these differences in environmental conditions likely shaped functional differences in the preen gland and its products. I measured the size of the preen gland and collected preen wax from a variety of forest passerines in Australia, New Zealand and New Caledonia. I found that island birds have larger preen glands and therefore likely produce more preen wax than their continental relatives. I also found that the preen wax composition differed among species, with a shift to birds on islands producing disproportionately lighter and more volatile compounds. I suggest that selection favoured the gain of more volatile molecules in island birds as they were released from the constraint to camouflage their odours that is imposed by mammalian predators on continental areas. It is possible that this also allowed greater communication through olfactory channels in island birds, and such communication is enhanced through the use of more volatile compounds. To support this hypothesis I showed that the South Island robin (Petroica australis) was able to detect and react to the odour of a conspecific (odours produced by preen wax) in the absence of any visual cues. From a conservation perspective, increased volatility of the preen waxes of island birds might place them at increased risk from introduced mammalian predators that use olfaction to locate their prey. However, in both laboratory tests using Norway rats (Rattus norvegicus), a common exotic predator, and in field trials using rodent tracking tunnels, I found only limited evidence to suggest the odour of island birds places them at greater risk, and more experiments are needed to test this hypothesis. Finally, my findings of more conspicuous odours in island birds suggest new avenues of research for their conservation, including whether island species that seem especially prone to predation have preen waxes (and thus odours) that are also especially attractive to exotic mammalian predators. Conservation programmes to protect endangered island birds may even benefit from considering whether olfactory cues can be minimised as a method of reducing predation risk.

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