12,113 results for Doctoral

  • Finding the Links between Knee Injuries and Osteoarthritis

    Leung, Sophia (2016)

    Doctoral thesis
    The University of Auckland Library

    The focus of this thesis was to accurately investigate how mechanical loading influences cellular functions of cartilage. The knee joint is one of the most complex organs in our bodies, and is also one the most susceptible to injury. Traumatic injuries to the knee joint can cause pain, instability, and misalignment that alter joint loading patterns. This in turn can cause a cascade of events that leads to the development of osteoarthritis. Therefore, there has been considerable research dedicated to understanding the onset and development of this disease. Research studies have tried to simulate in vivo joint loading in vitro by using mechanical devices to apply various loads on 3D chondrocyte (cartilage cells) seeded in hydrogel culture models, and then using gene expression techniques to identify the biochemical changes that may occur as a response of the loading. However, these in vitro models have often not been validated, and the mechanical devices used to apply mechanical loads do not simulate physiological joint loading. This has therefore led to the development of a precise multiaxial-loading device that can mimic physiological joint loading. In addition, a 3D hydrogel construct was also developed to withstand these mechanical loads. To validate our in vitro model, we first had to validate the hydrogels, which are inherently inhomogeneous. A strain distribution technique was first developed to determine the strain distribution of dynamic compression through different regions or zones of our hydrogel construct. Then, these construct strains were correlated with the cellular-shape change and angle of rotation of the cells subjected to dynamic compression, tension and shear loads in the different zones of the constructs to improve our understanding of how mechanical loads affect chondrocytes. Finally, gene expression techniques were used to determine the effects of applying different loading modes (compression, tension, shear, and a combination of the three) using our device, on chondrocyte mechanobiology. Two loading regimes, physiological and injurious loading were used. Our results showed that more physiological loading regimes promoted cartilage homeostasis, rather than increased anabolic activities, closely imitating the behaviour of in vivo chondrocytes. The system developed in this research has been the closest device capable of fully mimicking in vivo conditions in health and disease. Work here has significantly enhanced knowledge of chondrocyte mechanobiology. Continued work using the device and techniques developed in this work will advance towards clinical understanding of disease progression and treatment.

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  • The effects of habitat on phenotype, growth and fitness in New Zealand triplefin fishes (Family: Tripterygiidae)

    Caiger, Paul (2017)

    Doctoral thesis
    The University of Auckland Library

    New Zealand triplefins have previously been shown to have diverged in habitat use. This thesis aimed to determine whether they differed in habitat performance, with a view to determine whether processes that are hypothesized to have taken place over evolutionary timescales (i.e. ecological speciation), are evident over ecological timescales. Of particular interest is how variation in the environment can lead to fitness differences that have evolutionary consequences. This was achieved by testing several proximate indicators of fitness in different habitats, and included: (i) describing the patterns and variation in settlement and abundance of the four most common species of triplefins (Forsterygion lapillum, F. varium, Ruanoho whero, and Notoclinops segmentatus) among habitats, (ii) testing the effect of habitat on the relationship between male size and clutch size, (iii) utilising the age and growth rate information of two species of triplefin, F. lapillum and F. varium, as a proxy for post-settlement performance, (iv) testing the relationship between habitat and morphology in F. lapillum populations, and (v) testing the hypothesis that the mechanism for the environmentally-induced morphological variation seen in the wild populations (chapter 4) is phenotypic plasticity. Intraspecific variation was found in all of the ecological traits examined, with phenotypeenvironment correlations observed in density and reproductive output, growth rates and longevity, and fin and body morphology. The main factors associated with driving selection pressures were wave exposure and microhabitat type, and the former was consistently evident across all traits measured. Additionally, plasticity was shown to be the mechanism responsible for the observed morphological variation in F. lapillum, and theoretically has the potential to generate disruptive selection by creating the raw material for natural selection to act upon. By identifying characters under selection, these results suggest a basis for divergent selection in habitat use. This informs our understanding of niche diversification in triplefins and supports the hypothesis that differentiation in habitat use is an important mechanism in the ecological speciation seen in the New Zealand triplefin fish assemblage. As few field studies have examined this process in marine fishes, empirical studies of this nature on marine fishes are important in working towards an understanding of the drivers that promote and maintain diversity in these systems.

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  • Compressive Hyperspectral Imaging: Acquisition, Recovery, and Unmixing

    Lee, William (2017)

    Doctoral thesis
    The University of Auckland Library

    Hyperspectral imaging provides non-invasive, quantitative, characterization of materials' compositions via their spectral responses, demonstrating prospective developments in a wide range of scientific fields where contaminations from external sources could have a sizeable impact on what follows. The substantial overheads associated in handling the inherently massive volumes of hyperspectral data have unfortunately limited the number of practical applications by the stringent economic trade-offs. Nonetheless, recent advances in the field of compressive sensing (CS) have demonstrated great promise in alleviating the challenges faced in dealing with large data sets. In favour of this, the focus of this thesis is on the development of methods for integrating CS into hyperspectral imaging. A new pragmatic acquisition strategy based on CS is considered. Instead of directly extending CS acquisition to three-dimensions, where the sensing methods are currently impractical or unknown, the new strategy exploits the various acquisition modalities available in existing systems to compressively sense hyperspectral imagery using a hybrid of two-dimensional (2D) measurements, captured via the different modes. Using convex optimization, the necessary algorithm for recovery from the resulting CS measurements is developed and is shown to be easily integrable with existing recovery models. A detailed analysis revealed that practical single-mode 2D acquisitions that use a unique sensing matrix for hyperspectral CS fails to facilitate models that exploit sparsity beyond the measured dimensions, while for the same setup, the multi-modal approach achieved superior reconstruction, leading to an improvement between 3 to 14 dB in the signal-to-reconstruction error of real scenes over state-of-the-art recovery models. Two decoding models for the reconstruction of compressively sensed hyperspectral data are proposed which linearly combine the total variation (TV) of each spectral band with smoothness-inducing priors along each voxel of the hyperspectral image to achieve accurate reconstructions. The models are posed as convex optimization problems in the form of an l1- l2 gradient-based minimization, and an l1-l1 sparsity-based minimization to capture both the spatial uniformity exhibited in the bands and the spectral smoothness inherent in the voxels. Simulations with multiple datasets were conducted and comparisons were made against similar methods from the existing literature. The models were shown to be effective in all tested data with the gradient-based model outperforming by at least 6 dB in the reconstruction error metric. Finally, the problem of linear unmixing directly from CS measurements is considered. A blind unmixing technique is presented that forgoes strict, unrealistic, assumptions about the underlying data imposed in prior works including the absence of spectral mixing, and the absolute knowledge of endmember presence. The technique uses the smoothness characteristic exhibited by, and the external geometry of, the participating endmembers under the linear mixing model (LMM) for effective unmixing in a highly mixed scenario. The resulting algorithm alternately minimizes the TV of the abundances under the LMM, and the second central moment of the endmembers in conjunction to the their relative Euclidean distances. The technique was shown to be promising through experimentation on simulated dataset with various controllable parameters. While a number of challenges still remains to be further resolved in each area, the progress made in this thesis represents a significant step towards bridging the gap between hyperspectral imaging and the numerous applications that could benefit from it.

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  • Performance analysis of adaptive chaos-based DS-CDMA system with imperfect channel estimation

    Patel, Meher (2017)

    Doctoral thesis
    The University of Auckland Library

    This thesis presents the analysis of chaos-based direct sequence code division multiple access (DS-CDMA) systems under imperfect channel estimation environments. Chaos-based CDMA systems are studied extensively in the last few decades, but their performances under imperfect channel estimation conditions are never studied. The main motivation of the thesis is to fill this research gap under various possible conditions. The thesis focuses on three main objectives. The first objective is to determine the effect of spreading sequences in channel estimation processes. Here performances of channel estimators in the presence and absence of chaotic spreading sequences are investigated. The second objective is to study the performances of imperfect channel estimations in chaos based CDMA systems under various fading conditions. This part mainly focuses on the various factors which deteriorate the performance of the systems. The third objective focuses on the various techniques which can improve the performances of the systems. In this part various available techniques for CDMA systems are studied under imperfect channel estimation environments. It is concluded that performances of all the available chaos based CDMA systems significantly depend on performances of channel estimators. Analytical simulation results in the thesis show that performance degradation in available systems due to various fading channels can be significantly improved by using channel estimators.

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  • Children's Writing in New Zealand Newspapers, 1930s and 1980s

    Holt, Jill (2000)

    Doctoral thesis
    The University of Auckland Library

    Whole document restricted at the request of the author, but available by individual request, use the feedback form to request access. This thesis is an investigation of writing by New Zealand children in the Children's Pages of five New Zealand newspapers: the New Zealand Herald, Christchurch Press and Otago Daily Times in the 1930s and 1980s, the Dominion in the 1930s; and the Wellington Evening Post in the 1980s. Its purpose is to show how children reflected their world, interacted with editors, and interpreted the adult world in published writing, and to examine continuities and changes between the 1930s and 1980s. It seeks evidence of gender variations in writing. and explores the circumstances in which the social role of writing was established by young writers. It considers the ways in which children (especially girls) consciously and unconsciously used public writing to create a public place for themselves. It compares major themes chosen by children, their topic and genre preferences in writing, and the gender and age differences evident in these preferences. The thesis is organised into three Parts, with an Introduction discussing the scholarly background to the issues it explores, and its methodology. Part One contains two chapters examining the format and tone of each Children's Page. And the role and influence of their Editors. Part Two (also of two chapters) investigates the origins and motivations of the young contributors, with a special focus on the Otago Daily Times as a community newspaper. Part Three. of four chapters, explores the children's writing itself, in separate chapters on younger and older children, and a chapter on the most popular genre, poetry. The conclusion suggests further areas of research, and points to the implications of the findings of the thesis for social history in New Zealand and for classroom practice. The thesis contains a Bibliography and an Appendix with a selection of writings by Janet Frame and her family to the Otago Daily Times Children's Page in the 1930s.

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  • Unleashing the Power of Human Genetic Variation Knowledge: New Zealand Stakeholder Perspectives

    Gu, Yulong (2010)

    Doctoral thesis
    The University of Auckland Library

    This thesis reports a qualitative study that collected multiple perspectives of New Zealand genetic services stakeholders concerning genetic information management issues. With the rapid development of human genetic variation knowledge and medical testing technologies, the demand for clinical genetic services is expanding in many healthcare systems. There are, however, many challenges in managing genetic testing and understanding test results. Taking a grounded theory approach, semi-structured interviews were conducted with 48 participants in order to understand their experiences, expectations, and concerns. The interview data were triangulated with our field notes, literature, and by applying a semantic space modelling technique - hyperspace analogue to language. The data analysis took a general inductive approach with a constant analytic comparison strategy. Three themes emerged from the data that identify gaps in the use of information relating to genetic services. Firstly, four service delivery models were identified in operation, including both those expected models involving genetic counsellors and some variations that do not route through the formal genetic services program. Secondly, a number of issues were perceived by the participants as barriers to sharing and using genetic information, including technological, organizational, institutional, legal, ethical, and social issues. Thirdly, the wider use of genetic testing technology is also impeded by the mixed understanding of genetic test utilities, particularly among clinicians, and is limited by the capacity of clinical genetic services. Due to the effect of these three themes, the potential of human genetic variation knowledge to enhance healthcare delivery has been put on a "leash." Targeting these problems, information technologies and knowledge management tools may support key tasks in genetic services delivery, improve knowledge processes in the domain, and enhance knowledge networks. Promising technologies include decision support systems, electronic referral systems, electronic health record or personal health record systems, data submission and other knowledge processing tools, ontology, and knowledge networking tools. The establishment of effective ethics and policy frameworks is also important in leveraging the power of genetic information for better healthcare outcomes.

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  • Effectiveness of tailored nutrition education for improving household supermarket food purchases

    Eyles, Helen (2010)

    Doctoral thesis
    The University of Auckland Library

    Background There is a growing interest in tailored nutrition education, which personalises information to the individual. However, little research has been undertaken with priority population groups, or in supermarkets, where most food is purchased. Aim To investigate the long-term (??? six-months) effectiveness of tailored nutrition education for improving the supermarket food purchases of New Zealand adults, including priority groups. Methods A randomised controlled trial was undertaken in eight New Zealand supermarkets from February 2007 to February 2009. Participants were 1,104 ethnically and socio-economically diverse primary household shoppers 18 years and older. The trial compared tailored nutrition education, developed using a participatory approach, with control (no intervention). Household supermarket sales data were used to tailor education resources and to assess trial outcomes. The primary outcome was change in saturated fat purchased at six-months. Secondary outcomes were changes in other food and nutrient purchases at six- and 12-months. Two sub-studies which assessed aspects of internal validity of the trial were also undertaken. Results At six-months, the difference in saturated fat purchased by tailored nutrition education vs. control was -0.09% total energy (95% CI, -0.47% to 0.30%); p=0.66. Corresponding differences for purchases of saturated fat at 12-months and all other food and nutrient outcomes assessed (at six- and 12-months) were non-significant. Sub study one found 65% of all food purchases were made at participating supermarkets. The validity of household electronic supermarket sales data as a surrogate measure of individual nutrient intakes was also demonstrated. Sub study two demonstrated the validity of the modified Heart Foundation (HF) Tick nutrient profiling model to appropriately identify ???healthier??? options for promotion in the trial. Conclusion: Tailored nutrition education cannot be recommended as a stand-alone public health strategy for improving the supermarket food purchases of New Zealand adults. More effective approaches to improve population dietary intakes must be sought. Due to their Abstract iii potential reach and impact, supermarket-based nutrition interventions should be a medium for such approaches, and household supermarket sales data considered as an objective surrogate measure of effectiveness.

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  • The Epidemiology and Management of Hypothyroidism in General Practice

    Gibbons, Veronique (2011)

    Doctoral thesis
    The University of Auckland Library

    Hypothyroidism is a common condition in general practice. Evidence of long-term outcomes and the effectiveness of treatment for subclinical hypothyroidism are lacking. This thesis provides new knowledge to support practice in relation to subclinical hypothyroidism. Methods and Results Several research methodologies were utilised: ??? A cross-sectional study in general practice showed that prevalence of hypothyroidism in Hamilton City was 2.5%, with an overall level of thyroid dysfunction at 3.2%. ??? Examining retrospective laboratory data of thyroid function tests showed that 1 in 6 patients without known thyroid disease are tested within a 12-month period. ??? Focus groups of general practitioners found that patients with a raised thyroid stimulating hormone (TSH) assay posed a dilemma for general practitioners. ??? Retrospective laboratory data and note review of the management of patients with raised TSH found that two percent of patients were managed according to New Zealand Best Practice Advocacy Centre (BPACnz) recommendations. ??? Note review and interviews with patients with central hypothyroidism showed that a first-line TSH strategy was not the cause of delayed diagnosis but indicated a reliance on biochemical results over manifest signs and symptoms. ??? Survival analysis comparing patients with thyroid dysfunction against cardiovascular events and all-cause mortality found that patients with both subclinical and overt hypothyroidism had an increased risk of cardiovascular events [Hazards ratios 1.22 (1.12-1.33) and 1.58 (1.44-1.73)] and death [1.29 (1.17-1.42) and 1.45 (1.31-1.62)] compared to euthyroid individuals after adjusting for age, gender, ethnicity and social deprivation. The increased cardiovascular event risk was greatest in those under 65 years of age with subclinical hypothyroidism [1.26 (1.07-1.49)] compared with those 65+ years [1.14 (1.03-1.27)]. A systematic review of patients with subclinical hypothyroidism treated with thyroxine found that treatment had a positive effect on lipids, BMI, cardiac function and systolic blood pressure in individuals less than 65 years of age with stable subclinical hypothyroidism. Conclusions Subclinical- and overt hypothyroidism are associated with increased cardiovascular morbidity and all-cause mortality with the greatest excess risk in patients with subclinical hypothyroidism who are less than 65 years of age. Treatment with thyroxine should be considered in these patients to reduce cardiovascular risk.

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  • Identity matters: Racial-ethnic representations among adolescents attending multi-ethnic high schools

    Webber, Melinda (2011)

    Doctoral thesis
    The University of Auckland Library

    Racial-ethnic identity is a fundamental aspect of an early adolescent's identity because it includes the attitudes and feelings associated with ethnic and racial group membership. Literature shows racial-ethnic identity to be an important aspect of adolescents' developmental and psychological well-being. This is important in light of the increasingly diverse racial-ethnic demographic for New Zealand, particularly in our large cities. The present study is based around the broad research question 'What influences early adolescent racial-ethnic identity development?' This includes a fundamental question of 'How do early adolescents enact racial-ethnic identity in high school contexts?' and then, 'How does racial-ethnic identity impact on the way early adolescents engage at high school?' This study examines the importance of racial-ethnic identity among young adolescents who attend large, multi-ethnic, urban high schools in New Zealand. The project is comprised of one study with three parts. The analysis in this study focuses on a comparison of Year nine students (13-14 years old) in New Zealand from four racial ethnic groupings: New Zealand European/Pa??keha??, Ma??ori, Samoan and Chinese. Study 1a and 1b (n = 695) examined the self-identifications, feelings of connectedness, meanings and perceived consequences of adolescents' racial-ethnic identities using a questionnaire. In line with the literature, the findings from these two parts show that racial-ethnic identities are important for adolescents from all four ethnic groups; it frames who they are, where they belong, and what they are trying to achieve. Study 1c used semi-structured interviews to examine the relationship of racial-ethnic identity to educational engagement among high-achieving adolescents from the four ethnic groups (n = 31). Findings here indicated that enacting multiple social identities protected the adolescents from the negative pressures of stereotype threat, but their racial-ethnic identity influenced the ways they enacted their academic and other social identities in the school context; they were constantly, and consciously, contesting contradictory racial-ethnic stereotypes in each context. The research concludes that although racism is prevalent and powerful in the lives of adolescents, a strong racial-ethnic identity may provide adolescents with the capacity to not allow negative pressures to interfere with their educational engagement.

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  • Masculinity and the nation: Film narratives of the nation in 1930s and 1980s China

    Shen, Jing (2011)

    Doctoral thesis
    The University of Auckland Library

    This thesis compares Chinese films from the 1930s and 1980s to understand representations of Chinese masculinities in the two periods of rapid modernisation and nation-building. It encompasses three research topics. First, we discuss masculinity constructed responding to support Chinese nationalism. In Chapter One, Chinese modernity is manifested as an overwhelming sentiment for national salvation triggered by a history of imperialist invasion. The ideal Chinese masculinity therefore is revealed as doubly rebellious, both against corrupt authorities and traditions as well as against imperial powers. The films analysed are Big Road (1934) and Red Sorghum (1987). In Chapter Two, close readings of Wolf Hill (1936) and Evening Bell (1988) unravel a war metaphor, discovering an emerging masculine archetype assisting the formation of Chinese national identity. Second, we address male and female subjectivities as an expression of democratic consciousness. Examined within the framework of an imagined, modern public sphere, the films reflect competing views and stances towards democracy, a core part of the modern nation state. Chapter Three introduces Ju??rgen Habermas' notion of a bourgeois public sphere, where enlightenment attempts by males prevail. Crossroads (1937) and The Trouble Shooters (1988) are examined. In Chapter Four, a kind of female masculinity reflects a radical democratic stance, indicating a subversion of current political order. The central films are The New Woman (1935) and The Price of Madness (1988). The third theme of the thesis examines how masculinity serves individual identity contesting the ideology of the modern nation. In the last chapter, through close readings of Waves Washing Sand (1936) and One and Eight (1983), using the anthropological concept of the rite of passage, marginalised masculinity is discussed in combination with the questioning of sovereign power.

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  • Inside the city walls: Mental health service users??? journeys towards full citizenship

    Hamer, Helen (2011)

    Doctoral thesis
    The University of Auckland Library

    This study was undertaken at a time when mental health service users were lobbying to be treated as full citizens with the same participation, rights and responsibilities as other citizens. It explores mental health service users??? understandings of citizenship and whether the recovery approach helps or hinders their journey towards full citizenship. The study uses Isin???s (1999, 2002, 2008b) conceptual framework of citizenship to interpret data from indepth individual and focus group interviews with 17 service users and 12 key stakeholders. Isin???s conceptual framework focuses on the social, civil and political dimensions of citizenship. The overarching finding was that service users experience conditional citizenship, which includes barriers and restraints to their participation and to the rights and responsibilities that others in society enjoy. Conditional citizenship results from labelling which has its genesis in the bio-medical model, the predominant treatment approach used in mental health services. The labelling of service users leads to stigma and discrimination in wider society and results in service users being Othered. In an attempt to blend in with the rest of society service users shape their behaviour through self-surveillance and self-policing to mitigate risk to themselves and others. Additionally in an attempt to be accepted they engage in practices of inclusion. These practices include self-disclosing about their illness, working in education and leadership roles to bring about acceptance of those with mental illness, and the expansion of the prevailing behavioural norms. For service users, deeper, existential and spiritual connections with others is essential for their sense of belonging. In some cases they make a claim for their full rights by engaging in acts of citizenship such as private and public practices of responsible subversion. The findings from this study have important implications for the recovery approach that should ideally underpin mental health service delivery. The thesis concludes by outlining recommendations for nursing practice, nursing education and policy.

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  • Imagining possibilities: Trans representations in mainstream film

    Woodward, Suzanne (2011)

    Doctoral thesis
    The University of Auckland Library

    Trans representations have been a part of film since its inception, and this project is an investigation of the ways that audiences have been encouraged to imagine trans identities and experiences and understand trans issues. Because of the enduring and widespread popularity of these films, and the power and influence of the medium itself, it is important to understand what they enable for mainstream audiences as well as the role they play in cultural discourses about heteronormativity. The ways that the films construct trans narratives and characters tends to be closely tied to the genre they are intended to be part of, and they are understood according to these conventions. This project therefore uses genre analysis to examine mainstream trans representation, in conjunction with the developments in politics and academic discourses that have shaped contemporary understandings of trans stories. The project covers the four genres that dominate in mainstream trans films: comedy, horror, melodrama, and musicals. Each genre is dealt with in a separate chapter, but the links and intersections between them are explored as well. The chapters consider the particular influences, conventions, constraints, and innovations specific to each genre, through close reading of a few key texts, as a way of tracing the shifts that have occurred and the conventions that have endured, and offers suggestions as to why and how these elements survive or transform. Through tracing these developments, this project identifies the ways in which trans representations in popular film have played a role in developing and maintaining the trans visibility in mainstream society, and contributed to cultural discourses and understandings of trans issues. Despite the problems and stereotypes inherent in many of these films, they prevent trans identities from being erased or ignored. The films open up gaps in the heteronormative monolith, which can be ever be fully resealed, and which provide a space for other possibilities to be imagined.

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  • Growing innovative ventures ??? An investigation of individual-opportunity nexuses

    Fath, Benjamin (2011)

    Doctoral thesis
    The University of Auckland Library

    The importance of new ventures based on innovative products for economic prosperity has been frequently highlighted. However, the processes through which entrepreneurs create value on the market level using new ideas are not well understood. The objective of this thesis is to contribute towards the understanding of these processes. It starts out by providing a conceptualisation of the individual-opportunity nexus rooted in the entrepreneurship and the economic sociology literature. Against the backdrop of this literature, this thesis provides answers to questions as to how and why some individuals start innovative ventures; how these ventures are legitimised in a market; and how they are sustained given emerging rivalry. To study these questions, four types of opportunities for creating innovative ventures were distinguished. Using this distinction, seventeen cases were selected based on publically available information. Data collection involved twenty-two face-to-face interviews which were complemented using secondary data. The resulting case data base was then explored for cross-case patterns within and across the four types of opportunities. These comparisons were used to develop new theory about innovative ventures. The empirical results of this study show the existence of four individual-opportunity nexuses. These nexuses are not only relevant to how entrepreneurs become and stay involved in innovative ventures, but also to the challenges these ventures face. The study shows that there are distinct differences between the prior knowledge and the motivation of individuals pursuing a particular type of opportunity. Moreover, the type of opportunity pursued determines the challenges faced in legitimising innovative ventures. Whilst some entrepreneurs do not face major challenges in legitimising ventures or products, others have difficulties establishing their venture and/or their products as new economic entities. Finally, the study also shows differences regarding the intensity and the effects of emerging competition in the market of the innovative venture. Faced with these different environments, entrepreneurs need to aim at achieving fit between opportunity and strategy. Overall, this thesis contributes to the individual-opportunity nexus perspective of entrepreneurship and provides practical recommendations to individuals pursuing innovative ventures.

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  • Obesity-Related Metabolic Syndrome: Investigations into Novel Clinical Markers and Possible Causes

    McGill, Anne-Thea (2011)

    Doctoral thesis
    The University of Auckland Library

    Obesity-related metabolic syndrome (MetS) increases risks for degenerative cardiovascular disease (CVD), and has become widespread. Efforts to stem the increase of obesity are inadequate. New approaches to the problem may be required. Novel CVD Risk and Prediction Markers were investigated for use in enhancing the utility of MetS. Subsequently, a unifying hypothesis on causes of MetS was developed. MetS comprises central obesity, hypertension, dyslipidaemia and hyperglycaemia, but insufficiently reflects underlying oxidative, metabolic, inflammatory, and nutritional stresses. Novel CVD laboratory (1) Risk Markers; consisting of clinical routine screening haematology and biochemistry (CRSHaem&Biochem): Leukocytes: neutrophils; monocytes; lymphocytes; eosinophils; erythrocyte sedimentation rate (ESR); haemoglobin A1c (HbA1c); urate; ferritin; liver function tests (LFT): alkaline phosphatase (AlkPhos); alanine transferase (ALT); aspartate transferase (AST); gamma glutamyl transferase (??GT); bilirubin (2) Protective Markers; (a) serum fat cell-derived, adiponectin (Adpn) with oligomers (high, medium, low molecular weight (HMW, MMW, LMW) (b) serum fat soluble vitamins (sFSVitamins) beta carotene (s??Caro), vitamins (sVit)D, sVitA, sVitE, and VitK(INR) were investigated. Baseline, and mean over 6months (m), oxidants HbA1c and urate were strongly related to MetS marker count, a MetS index. Over 6m, on wide-ranging multivariable mixed modelling, ??GT and ESR changed with MetS marker count. Adpn showed anti- and pro-inflammatory correlations. sVitA and sVitE correlated with MetS marker count, and dyslipidaemia. s??Caro and sVitD correlated with protective markers. Thus 1) HbA1c, urate, ??GT, ESR, and 2) s??Caro, sVitD may be acceptable Novel CVD Risk and Protective Markers, respectively, for use with MetS. The unifying hypothesis on obesity and MetS was predicated on humans evolving proportionately large, energy demanding brains requiring co-adaptive mechanisms to: (1) increase dietary energy by developing strong neural self-reward/motivation systems for the acquisition of energy dense food and (2) economise on body energy metabolism by the co-option of many of antioxidant phytonutrients to confer long-lived cell protection. The study indicated that strong risk markers in MetS are oxidant, and associate with degenerative change, and antioxidant cytoprotection is augmented by plant food micronutrients, such as food-derived or dietary ??Caro (f??Caro). The unifying hypothesis was compatible with the study results. Whole-food diets need studying for prevention and reversal of MetS.

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  • Investigation of a Spinning Disc as a Thin Film Photocatalytic Reactor for the Degradation of Recalcitrant Wastewaters

    Boiarkina, Irina (2013)

    Doctoral thesis
    The University of Auckland Library

    Wastewater treatment is becoming increasingly important with the increase of pollution from municipal and industrial sources, driving the development of new processes for the treatment of the wide array of pollutants found in the environment. One such process is photocatalysis, an advanced oxidation process which uses a light activated semi-conductor catalyst to oxidise pollutants. The semi-conductor catalyst is usually applied in a powdered form. However, slow kinetics and mass transfer limitations have so far been hindering industrialisation and it is for this reason that new reactors are being investigated to overcome these limitations. The spinning disc reactor (SDR) is a process intensi cation technology which uses centrifugal force to spread a liquid onto a horizontally spinning disc into a thin lm. The SDR has two tuneable parameters, the ow rate and rotational speed, which allow for a range of ow regimes to form across the surface of the disc and exhibits enhanced mass transfer characteristics. This reactor has not been investigated in detail for its application as a photocatalytic reactor, and the aim of this thesis was to assess the e ectiveness of the SDR as a photocatalytic process intensi cation technology. Highspeed camera images were taken to observe the ow regime in order to select operational parameters representative of di erent operational parameters to be used for the experiments. The e ect of ow rate and rotational speed was investigated on the degradation rate of methylene blue and DHA, and aside from reaction rate maxima found at 15mL.s 1, the surface rate of reaction was constant between the di erent operational parameters. No correlation was found between an increase in the rate of reaction and the ow rate and/or rotational speed, implying that the reaction was not mass transfer controlled. Further investigation into the reaction rate maxima found at 15mL.s 1 and 100 and 200rpm showed that signi cantly enhanced primary molecule and intermediate degradation was caused by a change in the ow found with the highspeed camera images. Further investigation with methylene blue through the adjustment of the nozzle to alter the ow regime found that as the ow became more homogeneous the rate of reaction of the primary molecule increased. This makes the nozzle design an important design consideration in SDRs, which is normally overlooked. The reaction rate maxima of the degradation of methylene blue are likely the result of periodic forcing from the peristaltic pump enhancing the adsorption of the oxygen and/or enhanced electron transfer from the catalyst to the oxygen. Adsorption of oxygen and/or electron transfer to the oxygen are often found to be the rate limiting step in photocatalytic reactions. The enhanced oxygen would improve the charge carrier separation and through that the rate of reaction. The fast rate of degradation of methylene blue achieved with periodic forcing is 3.7 10 7mol.m2.s 1, which is seven times larger than that achieved without. Periodic forcing should be investigated as a possible method of intensifying reaction rate, for the spinning disc reactor and other reactors, as its enhancement e ect is in addition to the increased mass transfer already normally observed in this system. A comparison of the SDR and an annular reactor determined that the SDR is more complex to design, build and maintain. However, the SDR is signi cantly more e cient at utilising the incoming light, as the average photonic e ciency achieved in the SDR is an order of magnitude larger than the maximum photonic e ciency achieved in the annular reactor, 0:19 0:08% versus 0:062 0:009% respectively. Similarly, the average volumetric rate of reaction for the SDR was an order of magnitude larger than that of the annular reactor, 3:6 1:5 10 4 mol.m 3s versus 0:13 0:02 10 4 mol.m 3s, due to the signi cantly smaller volume in the SDR. The maximum surface rate of reaction achieved in the SDR was two times larger than the maximum reaction achieved in the annular reactor, 3:51 0:26 versus 1:66 0:22 107 mol.m 2.s 1 respectively. As the maximum reaction in the annular reactor included a strong degradation due to photolysis, which was not found in the SDR, the photocatalytic rate found in the SDR exceeded both the photocatalytic and photolytic degradation found in the annular reactor. This suggests that at this condition the rate limiting step is being overcome, and that when operated at this condition the SDR is performing as a process intensi cation technology.

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  • Miniaturized optical DNA sensors based on conjugated polymers

    Gular Srinivas, Anupama (2013)

    Doctoral thesis
    The University of Auckland Library

    The development of highly sensitive and selective DNA sensors has fuelled applications in a wide range of fields including medical diagnostics, forensics, biodefense, food contamination and environment monitoring. Recently, conjugated polymers (CPs) have drawn attention as attractive novel materials for biosensors due to their tuneable optical and electronic properties and ability to respond to minor changes in their environment. The aim of this research was to develop miniaturised optical DNA sensors based on photoluminescent CPs. Investigations towards the effect of systematically substituting carboxylic acid functionalized CPs with polar methoxy, mono-ethylene glycol, di-ethylene glycol and tri-ethylene glycol sidechains on the solubility, optical and electrochemical properties were conducted. The resultant CPs were characterised using a range of techniques such as nuclear magnetic resonance (NMR), fourier infrared spectroscopy (FTIR), ultra-violet (UV-Vis) visible spectroscopy and fluorescence spectroscopy. Furthermore, three different novel optical DNA sensors on magnetic beads were designed and developed using the synthesized CPs. DNA hybridisation was monitored using fluorescence resonance energy transfer (FRET) and superquenching readout methodologies. These sensors exhibit desirable characteristics such as ease of handling (through magnetic deployment). All the three different sensing platforms were able to discriminate mismatches in the target sequences, theoretical detection limits to target DNA concentrations were calculated between 0.01 pM and 18.8 pM, improving resistance to non-specific interactions with DNA and proteins, fulfilling the requirements for a selective, sensitive, mobile, costeffective miniaturised DNA sensor.

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  • Te Ana o te Raiona: M??ori Political Movements and the M??ori Seats in Parliament, 1867 ??? 2008.

    McDowell, Tiopira (2013)

    Doctoral thesis
    The University of Auckland Library

    In 1867 the New Zealand Parliament passed legislation to introduce four seats in the House of Representatives for the M??ori people, the indigenous tribes of Aotearoa-New Zealand. This thesis investigates the history of how M??ori Members of Parliament and M??ori political movements have engaged with the M??ori seats from 1867 to 2008. It asks a series of questions on the nature of M??ori political engagement with the M??ori seats: Why were the M??ori seats established and what role did M??ori communities play in their establishment? Why did M??ori choose to engage with parliament and how did they regard the M??ori seats? What types of leaders did M??ori political movements send to represent them, according to what criteria were those leaders selected, and how did M??ori attitudes towards leadership change over time? What did M??ori hope to achieve by sending their leaders to parliament, and what ambitions did those leaders carry with them? What have M??ori parliamentarians in the M??ori seats achieved and what factors have helped or hindered their efforts? How effective have M??ori MPs been in representing their constituents in Parliament and by what criteria should we judge their effectiveness? And how has M??ori political engagement with the M??ori seats changed over time? This thesis also looks to the cultural and social implications of political engagement, asking what impact M??ori culture, customs, language and social organisation had on M??ori political engagement, and in turn what impact did political engagement with the M??ori seats have on M??ori culture and society? To answer these questions this thesis discusses the establishment of the M??ori seats and the M??ori political movements that have engaged with these seats, covering the formation of the seats 1835-1867, the careers of M??ori MPs whose efforts and achievements are well established in the existing historical literature 1887-1943, the era of Ng?? m??t??mua the first wave of M??ori MPs 1868-1938, the R??tana-Labour era, 1932-1960, the political career of Matiu Rata 1963-1991, and the formation of the M??ori Party 1996-2008. This thesis employs a mix of primary documents, oral interviews and secondary sources to pull together a picture of M??ori political engagement with the M??ori seats over the past 145 years. It argues that historians have underestimated the role of the M??ori MPs and the agency of M??ori communities in determining the direction of political engagement. The M??ori MPs have been dealt with in a homogenous fashion and written off as ineffective and ill prepared for the rigours of parliament. A closer reading demonstrates that the M??ori MPs have made a considerable contribution to New Zealand society in pursuing the ambitions of their constituents, and that the M??ori seats play a significant role in the social, cultural and political landscape of the nation.

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  • Assertibility and coordination: Analysing `and' and/or `or', some `some', but not so much `but', `not', `so', or `nor', nor `much'

    Withy, Andrew (2014)

    Doctoral thesis
    The University of Auckland Library

    This thesis explores how far classical logic, combined with formal restrictions that model some Grice-inspired maxims, can go towards describing the multiple distinct uses of the English natural language connectives `and' and `or'. H.P. Grice famously claimed that `and' and `if' could be completely reduced to the truth-functional connectives `^' and ` ' plus his maxims, so this thesis partakes somewhat of the spirit of his project. However, it is neither Gricean nor neo-Gricean, as conversational implicature is ignored in favour of an appeal to formal and general predictions that can be drawn by an ideal rational cooperative Hearer. This allows the development of formal propositional systems based on norms inspired by Grice's cooperative principle and subsequent maxims. These formal systems seek to capture assertibility, and require some new approaches to logical semantics that are interesting in their own right. Many types of pragmatic phenomena can be described in terms of which minor deviations are required to the utterance form to meet the assertibility criteria. Many of these deviations can be described precisely by formalising additional maxims or borrowing some concepts from cognitive linguistics and formal syntax. Some of the functional-typological distinctions within each of the coordinations `or', `and', and `but' will be compared to a list of predictions produced by assertibility considerations. The principles behind propositional assertibility are then applied to predicate logic, negation, and speech acts such as interrogatives and arguments with some interesting results. An approach to conditionals (`if' clauses) and related subordinating conjunctions such as `when' and `since' is sketched based on linguistic classi cations and assertibility considerations. The assertibility conditions for disjunction also suggest an analysis of the so-called paradox of Free Choice that suggests it is both far more pervasive and simple than previously believed. Finally, the results of this exploration are tallied, along with some puzzles, surprising parallels, and thoughts for further research.

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  • Naturalising the Unity of Desires: Michael Smith on the Analysis of 'Right'

    O'Leary, Padriac (2015)

    Doctoral thesis
    The University of Auckland Library

    This thesis explores a neglected facet of Michael Smith???s meta-ethics in The Moral Problem. Although Smith claims to be a naturalist, he thinks that some popular accounts of a defensible naturalism in ethics fail. Thus he argues that a network analysis and reduction in the manner of Frank Jackson???s moral functionalism is vulnerable to a permutation problem and should be rejected. He also argues that a natural kind treatment of ethical terms forces the inappropriate categorisation of some possibilities as acceptable examples of moral relativism when they are not. By identifying and reconstructing the crucial role played in Smith???s argument by the notion of desiderative unity, the thesis argues that Smith???s own summary-style analysis and reduction of ethical terms either faces the collapse of his rationalist meta-ethical naturalism into a version of Jackson???s moral functionalism or requires that he treat ethical kinds as natural kinds, despite his arguments against such a possibility.

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  • The Development of PI3K Inhibitors as Anticancer Drugs

    Marshall, Andrew (2010)

    Doctoral thesis
    The University of Auckland Library

    Phosphatidylinositol 3-kinases (PI3Ks) are a lipid enzyme family that are vitally important regulators of intracellular signalling pathways which control cellular activities including cell survival, growth and proliferation. Deregulation of the PI3K signalling cascade has been observed in a broad range of human diseases including cancer, diabetes, thrombosis, immunity and inflammatory disorders. With the discovery of PI3K???s link to a variety of diseases, there has been a race to produce ATP competitive inhibitors as therapeutic agents against the Class I PI3K isozymes. Herein, compounds from two structurally distinct chemotypes were synthesised and their activity and specificity characterized against isolated Class PI3K enzymes and two cellular lines. The aryl morpholine containing pyrido[1,2-a]pyrimidines probed the requirements of the Class IA PI3K active sites through modification of the pendant C9 position. Interestingly, no compound synthesised exhibited superior activity towards the p110?? enzyme than TGX-221 (1.14). The second series of compounds probed the requirements of the thiazole-linked pyrazolo[1,5-a]pyridine 4.41B, identified through scaffold hopping studies using the novel p110?? selective inhibitor PIK-75 (1.34). Although 4.41B was not synthetically accessible, analogues explored alternative linkers and substitution of the 2-methyl-5-nitrobenzene ring, to investigate the effect on p110?? selectivity and potency. The sulfone-pyrazole linker group in (5.5) was found to be critical, with alternative linker groups in the thiazole series SO2CH2 4.123, CH2 4.122, CHOH 4.114 and linker absent 4.108 ablating activity, while activity was retained by thiazole-CH2SO2 4.124. As the complexes between the pyrido[1,2-a]pyrimidine and pyrazolo[1,5-a]pyridine chemotypes with the active sites of p110?? and p110?? respectively are not known, docking simulations were performed using structural p110?? models and p110?? (pdb:2RD0) respectively to understand the molecular basis for the isoform selectivity exhibited by the two chemotypes. Suitable docking methods were obtained by first investigating the ability of three docking protocols GOLD, SURFLEX and AutoDock to find and correctly rank an experimentally derived conformation both retrospectively (rescoring), where the compounds were docked back into the p110?? crystal, and prospectively, where the ligands were docked into the apo p110?? (2RD0).

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