22,935 results for Thesis

  • Thermochemical Behaviour and Stability of Aluminium Smelter Crust

    Zhang, Qinsong (2014)

    Doctoral thesis
    The University of Auckland Library

    In aluminium reduction cell, anode cover is added onto the anodes and the bulk bath to maintain the cell heat balance, as well as to reduce the anode air burn and fluoride loss. Alumina and crushed bath are the most common raw materials for the anode cover. Investigation and understanding of the thermochemical behaviour and stability of the crust is important for maintaining the cell heat balance. In a reduction cell, the anode cover at room temperature is heated by high heat flux from the hot bulk bath. Liquid bath appears in the anode cover due to the penetration of liquid bath from the bulk bath and melting of the crushed bath in the anode cover. The liquid bath penetrating upwards is cooled down by the cold upper part of the anode cover. As a result, the solid phases of cryolite and alumina crystallize out of the liquid bath, which reduces the cryolite ratio (CR) of the remaining liquid bath. The liquid bath and the precipitated crystals contribute to the formation of sintered crust at the bottom part of the anode cover. However, too much liquid phase in the crust can lead to the melting and weakening of the sintered crust. Based on the heat and mass transfer theory and phase equilibrium diagrams, a theoretical thermochemical model was developed to quantitatively simulate the thermochemical evolution process during sintered crust formation. An effective specific heat capacity was deduced to couple the temperature and chemical composition variables together. The thermochemical model was solved by a designed computational code applying finite element method (FEM). The simulation results were compared with experimental data. Seven crust pieces were taken from industrial reduction cells. According to their appearance, shape and crystal texture, three types of crystalline crust were distinguished from the sintered crust, and accounted for by crystallization from the bulk bath under different cooling rates. Crust samples were taken from different vertical positions in these crust pieces. XRD analysis, Rietveld refinements, and LECO oxygen analysis were carried out to analyze the chemical compositions of the crust samples. A non-commercial and calibrated DTA system was used to measure the liquidus and melting temperatures of the crust samples. The measured results show that cryolite content and CR are 60~70 wt% and 2.58~2.64 in the lower crust respectively, and decrease significantly to 20~30 wt% and 1.75~2.10 in the upper crust. The liquidus temperature of the crust sample is depressed by the decreasing of CR and by other fluoride additives, and is consistent with the measured chemical composition by XRD. The melting behaviour of the crust was studied by the shape analysis of the melting peak of the DTA heating curve. Crust samples with high cryolite content and CR have sharp peak shape indicating narrow melting temperature range. In chiolite enriched crust, high liquid bath content that incongruently melts from chiolite can melt solid cryolite over a wide temperature range with low energy intensity.

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  • Inhibitors of indoleamine 2,3-dioxygenase 1 (IDO1) for cancer therapy

    Tomek, Petr (2015)

    Doctoral thesis
    The University of Auckland Library

    Immune escape is a central hallmark of cancer. A tryptophan-catabolising enzyme indoleamine 2,3-dioxygenase-1 (IDO1) is a dominant immune escape mechanism in a broad range of human tumours and its expression is associated with a poor prognosis in cancer. Blockade of IDO1 by small-molecule inhibitors is a validated cancer therapy and two IDO1 inhibitors are showing promise in human clinical trials. The work in this thesis contributed to an overall goal at the Auckland Cancer Society Research Centre to identify and investigate the mode of action of novel IDO1 inhibitors as potential anti-cancer agents. It entailed the establishment of a sensitive and automated IDO1 enzyme assay to screen compound libraries for potential drug development leads. The new fluorescence IDO1 enzyme assay developed in this work is 30-fold more sensitive (limit of detection 153 nM N-formylkynurenine) than pre-existing assays. It is economical and features low interference from test compounds. The assay utilises a fluorescing tetrahydroquinolone adduct formed in a chemical reaction between Nformylkynurenine and cyclic amines involving transamidation and amine rearrangement, not previously described. This assay was automated and used to screen the National Cancer Institute Diversity Set III library (1,597 compounds) and to validate the thirty hits obtained from the screening of a commercial library of 40,000 molecules. This afforded eight IDO1 inhibitors from which pyrimidinone, indolonoxide, and isoxazole classes emerged as suitable drug development leads. All three showed excellent cell permeability and good potency (IC50 0.066 - 8 ??M) in cell-based assays with negligible cell toxicity. Three of the top eight hits, including pyrimidinone, blocked IDO1 activity reversibly, identical to a well-studied IDO1 inhibitor, 4-phenyl-1H-imidazole. The other five hits, including isoxazole, elicited essentially irreversible IDO1 inactivation, an inhibitory mechanism not previously documented for IDO1 inhibitors. Testing the NCI library against serine-167 and cysteine-129 alanine replacement IDO1 mutants, established that serine-167 but not cysteine-129 in the IDO1 active site, is important for the binding of a broad range of inhibitors. This project discovered three novel IDO1 inhibitors suitable for drug development. The isoxazole lead is currently being optimised by rational medicinal chemistry for development as a potential anti-cancer drug for the future.

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  • The Neuropsychological and Functional Outcomes of Primary Intracerebral Haemorrhage (ICH) at 6 and 12 Month Follow Up: A Population-Based Study

    Wright, Natasha (2016)

    Doctoral thesis
    The University of Auckland Library

    This exploratory population-based study examined the short-term (6-month) and long-term (12-month) mood, cognitive, and functional outcomes of Intracerebral Haemorrhage (ICH). Previous research has tended to use hospital-based samples; examine stroke outcomes generally rather than specific to stroke subtype; assess outcomes only in the acute phase post-stroke; and favour functional outcomes, while neglecting neuropsychological outcomes. The aims of the current study, therefore, were: to compare 6- and 12-month outcomes of ICH survivors to matched controls; to describe the natural course of recovery of mood, cognitive, and functional outcomes over the first year post-ICH; to examine the interrelationships between mood, cognitive, and functional outcomes of ICH; and to determine if there are characteristics of the ICH survivor at baseline that predicts good versus poor functional and cognitive outcomes at 12 months. The study used a sample of 35 ICH survivors drawn from the Auckland Regional Community Stroke (ARCOS) IV Study and 34 healthy controls matched for age, gender, and ethnicity who were recruited from the Auckland community. Both the ICH group and the control group were administered a series of measures assessing their mood, cognition, and functioning (independence in activities of daily living [ADLs] and health related quality of life [HRQoL]). The ICH group were assessed, where possible, at three timeframes: baseline (within 2 weeks of ICH), 6 months post-ICH, and 12 months post-ICH. The results indicate that cognitive impairment following ICH is common, widespread, and persisting. Mood difficulties, particularly mild depression, were also present for ICH survivors over the study period. The ICH group had significantly less independence in ADLs, although improvement over the 12 months was observed. There were mixed findings when it came to HRQoL. Physical HRQoL post-ICH was impaired but not necessarily mental HRQoL. Younger age was found to correlate with poorer mood outcomes. Given the exploratory nature of the study, and limited power due to a small sample size, the findings are not considered conclusive. However, the results highlight the need for a greater focus on cognition and mood in rehabilitation of ICH survivors and on future research in these areas.

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  • Surgical Nurses' Non-technical Skills: A Human Factors Approach

    Marshall, Dianne (2016)

    Doctoral thesis
    The University of Auckland Library

    This research is the first to explore the social and cognitive non-technical skills (NTS) required of nurses practising in general surgical wards, the first to identify a taxonomy of NTS for general surgical nurses and the first to identify the differences in levels of performance of the NTS between experienced and less experienced nurses. There is increasing evidence that poor performance of these skills by health professionals at the ???sharp end??? of healthcare is a significant factor contributing to preventable adverse patient events. The study was conducted in four general surgical wards in a metropolitan hospital in a large city in New Zealand using a Human Factors (HF) approach. Part A, the first stage of the study, involved non-participant observations of fifteen nurses and used an inductive process to identify a taxonomy of seven NTS required of the nurses in their roles in surgical wards. These skills are communication, teamwork, situation awareness, decision-making, leadership and management, planning, and patient advocacy. Part B, the second stage of the study, used applied cognitive task analysis (ACTA) to determine the key cognitive skills that nurses use in challenging situations and to determine the differences between experienced and less experienced nurses??? practice. This involved a series of semi-structured interviews with six registered nurses. In conclusion, this research has developed a taxonomy of general surgical nurses??? NTS, both social and cognitive, identified the cognitive demands and cognitive processes of nurses pertaining to challenging events, and has provided an understanding of the differences in decision-making between experienced and less experienced nurses. The study has also identified gaps in nursing practice and nursing knowledge that can compromise the safety and effectiveness of the healthcare provided to patients. The findings from this research have significant implications for professional nursing practice and nursing education and point to a requirement for NTS training to be introduced into the nursing education curriculum and to be part of continuing professional development for nurses working in clinical settings.

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  • Psychologists??? Views and Experiences of Antidepressant Treatment for Depression

    Calkin, Jacinda (2016)

    Doctoral thesis
    The University of Auckland Library

    Research has raised doubts about the effectiveness of antidepressants, particularly for mild to moderate depression, as well as concerns about associated adverse effects of the medication. Despite these concerns and the relative efficacy of psychotherapy, antidepressant use continues to rise while the use of psychotherapy as a treatment for depression has declined. This qualitative study aimed to investigate psychologists??? views of antidepressants arising from their experience of working therapeutically with depressed clients. In particular, it sought to understand the experiences that influence psychologists??? views about antidepressants, any dilemmas they experience in regard to working therapeutically with depressed clients, and the approaches (including decision-making) they adopt in relation to antidepressant treatment and psychotherapy for depression. Sixteen clinical psychologists, with a minimum of five years??? experience, were recruited via an advertisement. Six of the psychologists were male and ten were female. Primary employment was distributed evenly across the public mental health system and private practice. The psychologists participated in semi-structured interviews focussed on exploring their experiences and views of working therapeutically with depressed clients, specifically those who have used or are using antidepressants. A process of thematic analysis, guided by an interpretive approach, was conducted on the data. The results of the thematic analysis showed that psychologists??? views of antidepressants are influenced by a number of experiences. These included the dominance of the medical model in the mental health system; their work context ??? private or public; their observations of the impact of antidepressant treatment and therapy on client wellbeing; and the influence of factors relating to the client. The subsequent approaches adopted by psychologists in relation to antidepressant and/or psychotherapy treatment for depression centred on client wellbeing and involved balancing a desire to empower the client with the importance of being pragmatic. Overall, antidepressant treatment was deemed useful to the extent that it improved client wellbeing; however when it disempowered the client and/or prompted disengagement from therapy it was viewed as compromising recovery by preventing clients from addressing the underlying causes of depression and acquiring coping skills, which could help prevent relapse in the future. Whilst holding these views, the psychologists ultimately respected clients??? choices and approached the treatment of depressed clients on a case-by-case basis. A model is proposed to represent these influences on psychologists??? views of antidepressants and the approaches they adopt when working with depressed clients. This study contributes a new and important perspective on client antidepressant use and psychotherapy to the field of research on depression, and considers implications for psychology/psychotherapy practice and future research directions.

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  • Ecological impacts of supplementary feeding on urban bird communities in New Zealand

    Galbraith, Josie (2016)

    Doctoral thesis
    The University of Auckland Library

    Millions of people worldwide engage in the practice of feeding birds. Although there are many purported impacts associated with bird feeding ??? including improved winter survival, increased reproductive success, increased aggression, and disease outbreaks ??? there has been little consideration of both the human and ecological consequences of the practice from the scientific community. The majority of bird feeding takes place in urban areas, yet in situ experimental studies of the effects are extremely rare. The practice of feeding is particularly poorly studied in New Zealand. In this thesis I investigate bird feeding and its impacts in New Zealand, to determine what risks bird feeding poses to urban bird communities in this context. The study consisted of two main components. First, a mail survey of feeding practices in six cities nationwide was carried out, to quantify the current feeding practices and motivations for feeding in New Zealand and identify potential risks from typical feeding practices. Results confirmed that bird feeding is a common activity, with 46.6% of households feeding birds. Bread was most commonly provided, with an estimated 5.1 million loaves/annum fed to birds across the six surveyed cities. Two key risks identified were: 1) that introduced birds are likely to be the main consumers of supplementary food sources in New Zealand; and 2) that poor hygiene practices may contribute to transmission of disease at feeders. Second, a 2-year in situ experiment was conducted to examine the impacts of typical feeding practices on local bird community structure and disease transmission; volunteer households in urban Auckland provided food for 18 months. The grain-based feeding regime caused a significant shift toward communities dominated by a few introduced bird species at feeding compared to non-feeding properties. House sparrow (Passer domesticus) and spotted dove (Streptopelia chinensis) particularly benefitted. There was a detrimental effect on one native insectivorous species, the grey warbler (Gerygone igata), which did not utilise the feeders. Disease risks were identified in feeder-visiting bird species, with all pathogens and parasite groups detected in at least one of the three focal species screened (house sparrow, silvereye Zosterops lateralis, and Eurasian blackbird Turdus merula). Feeding stations tested positive for Salmonella enterica Typhimurium on ~7% of occasions, confirming that structures used in feeding are a potential transmission pathway. Feeding had varying effects on disease dynamics, including no change on infectious pathogen parameters, and both positive and negative effects on parasitic infection parameters. The overall findings of this research confirm that bird feeding is a popular activity in New Zealand, one that generates positive feelings for those participating. Moreover, this research confirms that the practice of bird feeding has discernible consequences for urban bird communities. Further investigation into the effects of feeding is certainly warranted, and all conservation practitioners should take into account bird feeding as an important driver of avian ecology in urban ecosystems.

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  • Shape-restricted Density Estimation for Financial Data

    Liu, Yu (2016)

    Doctoral thesis
    The University of Auckland Library

    The motivation of the study in this thesis is about how to estimate an asset return distribution in finance that is often skewed, high-peaked and heavy-tailed. To avoid misspecification which is possible for a parametric model, we turn to nonparametric methods to estimating a density function. There are many nonparametric approaches, such as kernel-based and penalty methods, to solving estimation problems, but they may easily fail to satisfy some practically known properties or have difficulty in choosing the value of the bandwidth or tuning parameter. By contrast, one can avoid these issues by imposing certain shape constraints on the density function, that appear very reasonable from a practical point of view. Nonparametric density estimation under shape restrictions offer many advantages, such as having the required shapes, easily described fitted models and possibly a higher estimation efficiency. Specifically, we are interested in estimating a density function that is log-concave, or unimodal with heavy tails. Three main objectives are addressed in this thesis. Firstly, nonparametric maximum likelihood estimation of a log-concave density function is investigated. In particular, a new fast algorithm is proposed and studied for computing the nonparametric maximum likelihood estimate of a logconcave density. Theoretically, the characterization of the nonparametric maximum likelihood estimate is studied and the algorithm is guaranteed to converge to the unique maximum likelihood estimate under log-concavity constraints. Numerical studies show that it outperforms other algorithms that are available in the literature. Tests for log-concavity based on the new algorithm are also developed. Secondly, nonparametric estimation under smoothness and log-concavity shape assumptions is studied. We propose several new smooth estimators based on the maximum likelihood approach by employing piecewise quadratic functions for the log-density function. This leads us to define a log-concave distribution family that allows the second derivative of the log-density to change the direction of monotonicity at most once. Algorithms for these likelihood maximization problems are developed. Numerical studies of simulated and real-world data show that the new smooth estimator has the best performance of all nonparametric estimators studied. We also apply our smooth estimator to the receiver operating characteristic curve estimation, with good results obtained. Finally, we study the problem of estimating a unimodal, highly heavy-tailed distribution, as normally seen in financial data. A novel idea is proposed that it imposes log-concavity on the main body, and log-convexity on the tails. With the corresponding algorithm developed, the new shape-restricted estimator very much dominates the other ones for both simulated and real-world financial data, by providing excellent, nonparametric fits to the data in both the center and tails of the distribution. Bootstrap testing for identifying the function form implied by the new estimator has been developed. Tail performance is further studied in great detail and an application to Value-at-risk estimation is investigated. As a matter of fact, the study provides a very general approach to nonparametric density estimation under shape restrictions. Different pieces of shape restrictions can be combined easily in a seamless way, with fast computing algorithms available. Shape-restricted estimation is able to provide more accurate estimates compared with unconstrained estimates, and the work reported in this thesis lies a promising foundation for many more shape-restricted estimation methods to be developed and applied in the future.

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  • Implications of Urban Form on Suburban Food Production Potential: The Case of Auckland City-New Zealand

    Munya, Andrew (2016)

    Doctoral thesis
    The University of Auckland Library

    This research examines the relationship between urban form and the contribution of urban agriculture to food energy requirements. It is an empirical study on suburban areas of Auckland, New Zealand, that investigates the impact of housing density on solar access, soil and rainwater collection for the purpose of food production. Three typical suburban residential blocks of differing density were evaluated using a modified Land Suitability Analysis with solar access, soil fertility and water availability as primary determinants of suburban agriculture. The results were then extrapolated to the cities of Auckland and Christchurch to determine what proportion of the cities have a degree of food resilience. The findings show that if 25% of the back and front yards of residential lots in low-density suburbs of Auckland and Christchurch were utilized for food production, they would contribute 9.4% and 12.3% respectively to the overall diet of those urban areas. This is a significant amount of food energy requiring virtually no energy to transport it from producer to consumer. On the other hand, medium and highdensity urban forms contribute less than 1% of the food diet in both cities. The original contribution to knowledge is that for urban agriculture to be effective, lower density suburban housing is required with a relatively large surface area exposed to solar radiation. Although this results in increased resilience and allows a degree of self-sufficiency, it conflicts with urban containment policies that view low-density suburbia as a high transport energy consumer. The thesis argues that this potential form of food energy should be balanced against the negative aspects of transport energy consumption associated with suburbia. Policy directed at containment of cities ignores the potential contributions from renewable energy, particularly solar, that can be used for biomass (food) or directly converted to electricity or home heating.

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  • ???It takes a village to raise a child???: Pastoral Care for M??ori and Pasifika secondary school students

    Barber, Charmaine (2016)

    Doctoral thesis
    The University of Auckland Library

    There is a paucity of research on pastoral care in New Zealand schools, yet the extant literature endorses the value of pastoral care for secondary students. For M??ori and Pasifika students, pastoral care may enable the blending of M??ori/Pasifika models of health/wellbeing with socio-ecological models such as that of Bronfenbrenner (1979), in the school context. Improved student wellbeing could foster better school retention and participation. Pastoral care, therefore, holds potential to be the nexus of health and educational needs in the school setting for the increasingly diverse secondary student population. The purpose of this study was to explore and interpret what pastoral care is in the New Zealand context, how it is understood, as well as how it is represented and co-ordinated both within and beyond the school environment. A case study design was used to research this phenomenon utilizing interviews, observations and document analysis. The study found that the commonalities, as well as the notable differences both inter- and intra- ethnically within M??ori and Pasifika populations necessitate additional professional development in cultural responsiveness for all school staff, and other adults contributing to the school context. Culturally responsive pastoral care for students encompassing the whole child, and their families, looks likely to be the essence of a more nurturing school environment. In relation, M??ori and Pasifika student voice indicated that they require improved processes in order to increase participation, engagement and retention at school. Students in lower decile schools will need increased funding in order to compensate for the layers of disadvantage that are predominantly anchored in historical inequities, but persist through the perpetuation of discriminatory structural inadequacies. The findings argue that these disparities need addressing with a fresh approach in order to benefit M??ori and Pasifika students, but also New Zealand society at large.

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  • Does pre-training reduce the cognitive load of learning complex science information in authentic settings: science classrooms?

    Haslam, Carolyn (2016)

    Doctoral thesis
    The University of Auckland Library

    This study investigated the cognitive effects of employing the strategy of pre-training on students learning of complex ideas in science. A preliminary study confirmed that learning graphing skills in physics was a suitably complex and appropriate context for the main study. Students from three classes in each of eight different secondary schools were involved in learning science ideas using multimedia presentations in the topic of motion, which includes graphs, in their own classrooms. The students were all novices for this topic. This study contrasted the use of pre-training as a strategy to reduce the cognitive load and enhance the understanding and learning of complex information with no pre-training. The experimental treatment group received pre-training before being presented with the science ideas (teaching), the other two groups only received the teaching, Treatment group 2 once through and Treatment group 3 twice through. Cognitive load measures (during and after learning) were employed and performance measures included the difference between pre and post test scores, for high and low level learning, and for calculation and graphing ideas. In addition instructional efficiency was calculated. The effect of the pre-training strategy on males and females, different decile schools, and different enthnicities in New Zealand were also investigated. Results suggest that pre-training reduced the cognitive load and improved learning when complex information in science was presented and increased instructional efficiency for all students irrespective of gender, decile, and ethnicity when learning in an ecologically valid setting.

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  • The Long Term Implication of RTLB Support: 'Listening to the Voices of Student Experiences'

    Pillay, Poobie (2009)

    Masters thesis
    University of Waikato

    This research inquiry is based on the narratives of six secondary school male students who tell of their experiences of having learning and/or behaviour difficulties in school.The research explores the perspectives of these six participants, from one New Zealand Secondary School, who received support from a Resource Teacher Learning and Behaviour (RTLB) from a single RTLB cluster. The RTLB service is a school based resource that provides itinerant specialist support to schools and work with regular class teachers to improve the educational outcomes for students with moderate learning and/or behavioural difficulties (Ministry of Education, 1999; Walker et al, 1999). This study aims to capture the voices of the participants through narratives and to tell of their experiences with RTLB, their school and what makes sense in their lives. The purpose of this research is to induce reflection, themes or possibly questions for further discussion or research. There were four questions that drove this research inquiry: 1. What were the experiences of the participants who received support from the RTLB while they were at primary, intermediate or secondary school? 2. What were their current experiences of school life? 3. What is it about boys and school- especially those with learning and behaviour difficulties? 4. Were there any new insights available to support/extend the work of the RTLB in this cluster? A narrative approach was chosen as the methodology because it allowed the stories of the students to be told in their own voices. The principles of a narrative guided the construction, presentation and application of the interviews. The interviews were informally conducted and the transcription formed the narratives in this inquiry. The themes from the narratives generated discussion about the family as an important factor in raising positive, well balanced children. The similarities between the Caucasian participants and the Māori participants of the Te Kotahitanga project also featured. The themes also cover the impact of immigration on the South African participants and show the differences between the two school systems and how they affect students new to New Zealand. The impact of RTLB support was greatest on those who remembered quite clearly the RTLB and the support they received. The research presented a positive outlook for the participants despite their difficulties and experiences of school. Their resilience and the combination of support they received at school and home were important contributors to this optimism. The analysis of the narratives provided the RTLB in this cluster with some implications to support or extend their work. The implications included the development of proactive connections and meaningful relationships with the student. This was possible by getting to know them better and by making them aware of the purpose of RTLB involvement. The students could also be included in the problem solving and intervention processes. Two recommendations from this research are that future research could investigate a system to monitor progress of students who received RTLB support and a process to place immigrant children correctly in the New Zealand school system.

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  • Ghosts in the System: The Shaping of Professional Identities within the Organizational Culture(s) of a Private Training Establishment in Auckland, New Zealand

    Breedt, Andre (2016)

    Doctoral thesis
    The University of Auckland Library

    The business strategy of ???rolling intake??? (or continuous enrolment) defines the lived realities of teachers and academic managers in private language schools. Embedded deeply within institutional processes, it becomes an unquestioned systemic feature. As an operating principle, it serves as the catalyst for an organizational culture of perpetual crisis management, characterized by short-term thinking. Pedagogically suspect, ???rolling intake???, at best, complicates the professional practices of teachers and academic managers. At worst, it is a major contributor to the job insecurities of language teachers in the private sector. Founded on two research periods collectively spanning one year, this ???at-home??? ethnographic study (Alvesson, 2009) sought to investigate how five teachers and four academic managers negotiated the professional challenges they faced, individually and as a community, while working in a private training establishment (PTE) in Auckland, New Zealand. On a certain level, the research project represents an examination of the relationships between stakeholders??? professional identities, the people they teach, and the working environment. More profoundly, as arrived at through grounded theory (Charmaz, 2006), the study implicates ???rolling intake??? and other systemic ???innovations??? as instrumental in rendering teachers and their pedagogic concerns invisible. In this thesis, I demonstrate how, despite an inherently anti-social system subordinating pedagogic concerns to a commercial ethic, teachers keep on teaching, and learners keep on learning. They do this through individual acts of resistance which defy the cold rationality of a profit-oriented system, while also avoiding the myopic gaze of audit regimes that cannot capture the complexities of educational practices.

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  • Unravelling Genome Structure and Function through Experimentally Informed Polymer Models

    Pichugina, Tatyana (2015)

    Doctoral thesis
    The University of Auckland Library

    The genome is the primary information storage system of the cell. However, it is not fully established how eukaryotic and prokaryotic genomes are organized and function within cells. To fill this gap I used experimentally informed polymer models to reconstruct the 3D structures of the Schizosaccharomyces pombe and Escherichia coli genomes. I generated 3D models of the E. coli chromosome that were non-specifically compressed within cells. These models have shown that at the scales of several kb the E. coli chromosome organization cannot be described as random chromosome packing, while at scales starting from several tens of kb the E. coli chromosome is highly mixed and entangled. The polymer models of the S. pombe genome provided evidence that chromosomal interactions, detected by conformation capture experiments, play a structural role in S. pombe genome organization. I used ensembles of the S. pombe genome structures to construct 3D maps of genes, epigenetic marks, and replication origins. The 3D maps demonstrated that the S. pombe genome is highly compartmentalized. I found that highly transcribed genes and active epigenetic marks (H3K4me) are preferentially located toward the S. pombe nuclear interior, and inactive epigenetic mark (H3K9me) towards the nuclear periphery. The 3D maps of genetic elements that I generated represent a significant step towards the development of unified models for spatial gene regulation, DNA repair and replication.

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  • Cytisine concentration-effect relationships in human smokers

    Jeong, Soo (2015)

    Doctoral thesis
    The University of Auckland Library

    Cytisine is a plant alkaloid that is a partial agonist for the ??4??2-nicotinic acetylcholine receptor and is used as a smoking cessation medication (Tabex??). Double-blind, randomised, placebo-controlled trials show that cytisine is more effective than placebo in achieving long-term, continuous abstinence from smoking. At the start of this PhD there was no published information on the pharmacokinetics and metabolism of cytisine in humans or indeed, whether there is any relationship between cytisine exposure and effect. The main aims of this thesis were therefore: to obtain basic pharmacokinetic data for cytisine in humans, to study the effects of cytisine on physiological and psychological measures in smokers and to explore whether these effects could be related to the plasma concentrations of cytisine in human smokers who were instructed to adhere to the standard dosing regimen of Tabex?? In order to study the human metabolism and pharmacokinetics of cytisine, a sensitive analytical method using mass spectrometry (LC-MS) was developed and validated. This method was used to support the subsequent pharmacokinetic studies. In the first study, seven participants took a single dose (3 mg) of Tabex?? and blood samples were collected at various times up to 24 hours. Cytisine plasma concentrations were measured. In the second study, another set of participants (n=11) took Tabex?? using the standard 25-day dosing regimen recommended by the manufacturer. Blood samples were collected and cigarette craving, withdrawal, mood and smoking satisfaction were measured using self-report methods validated in the literature. Following a single dose administration, cytisine peak plasma concentrations typically occurred at 2 hours. Following this, cytisine concentrations declined in a monophasic manner with a mean half-life of 4.8 hours. No metabolites were detected. In the second study, accumulation of cytisine in plasma was observed on day 1. However, with the recommended dosing regimen, cytisine does not reach steady state concentration in plasma. There was also large between-subject variability in cytisine pharmacokinetics. Cytisine appeared to reduce cigarette cravings, but there did not appear to be a simple relationship between craving and cytisine plasma concentration. In summary, this thesis presents the first reported human cytisine pharmacokinetic data. The information gained from these studies may be used to inform the design of future trials that explore different dosing regimens of cytisine.

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  • Second language development, language learning motivation and language learning opportunities: A longitudinal case study of German high school exchange students in New Zealand

    Sauer, Luzia (2017)

    Doctoral thesis
    The University of Auckland Library

    This thesis reports longitudinal case studies of three female German high school exchange students in New Zealand. The students had advanced English proficiency levels at the beginning of their 5.5 month stay and were part of a large cohort of fee-paying international students who shared the same first language (L1) in the high schools where they chose to study. The study combines a detailed analysis of the students L2 development along with an analysis of the learners??? language learning motivation, the social contexts in which they operated and the opportunities that these afforded for language learning. The data collected consisted of weekly diary entries, monthly reports, and six individual audio-recordings of monthly semi-structured interviews. A qualitative data analysis was performed to scrutinize the students??? motivation and language learning opportunities as evidenced in their self-reports. A quantitative data analysis was carried out to capture developmental patterns in speech performance, using various measures of L2 complexity, accuracy, and fluency. Language learning opportunities were dynamically constructed between the students and their socio-cultural environment and were unique for each student. The students??? involvement in their L1 communities presented a challenge to the creation of L2 learning opportunities. Each student???s motivation was affected by a complex interaction between their goals, identities, and agency, and their perceptions of their L2 communities. The efforts they expended varied and were most clearly evident in social groups that gave them access and validated their sense of self. The students??? L2 development was non-linear and differed individually. Only the results for fluency were consistent, pointing to overall improvements. Findings for accuracy and complexity varied. Some trends, such as a decrease in lexical complexity, have not typically been observed in previous SA studies. A key finding was that the students??? L2 development was characterized by their adaption to the speech patterns of their native speaker interlocutors over time. The thesis provides a detailed, longitudinal account of the motivational and linguistic processes that characterize study abroad, providing insight into how and why learners perform differently in seemingly identical contexts of learning, and in this way adds to the existing literature on study abroad.

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  • Stories of Survival and Resilience: An enquiry into what helps tamariki and rangatahi through wh??nau violence

    Walters, Anna (2016)

    Doctoral thesis
    The University of Auckland Library

    Family violence is overrepresented amongst M??ori, the indigenous people of Aotearoa/New Zealand, and as elsewhere has been found to have significant consequences for children. Extant research has been predominantly deficit-focused. The current project focused on protective factors and resilience. Semi-structured interviews were conducted with professionals working with M??ori who had experienced wh??nau (family) violence as tamariki/rangatahi (children/youth) and survived through this difficult experience. Thematic analysis of transcripts revealed several dominant themes. These included that resilience is a complex concept, internal resources of the child contribute to resilience (involving inherent qualities, having an understanding of wh??nau violence, having dreams, hope for the future and goals, and self-belief in their abilities), having a significant, supportive person in their life, having a strong positive M??ori identity and having a wairua connection. Interventions to assist the development of resilience were also identified including building a relationship, early systemic interventions and using M??ori guided interventions. Implications of these findings include the importance of staff in the helping professions being able to develop effective therapeutic relationships with tamariki/rangatahi and attend to these factors thought to promote resilience.

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  • The influence of acculturation on conflict management styles of Chinese and Indian SME owners in Auckland metropolitan.

    Khirsariya, Poonam (2015)

    Thesis
    Unitec

    Commonly SMEs are owned and managed by a working owner who makes most of management decisions. Most of these SMEs do not have access to specialist staff with management expertise nor are they a part of large businesses or group of companies with managerial expertise. Most of SME owners commonly rely on building their management expertise through experience (Ministry of Business, Innovation & Employment, 2012). An organisation’s culture and management practice usually ascend from beliefs, values and assumptions of the founder’s learning experience of group members as an organisation evolves. An organisation’s culture evolves from the founder’s own cultural identity, personality, self-confidence and determination (Schein, 1992). Conflict is inevitable in organisations Jehn, Rispens, Jonsen, and Greer (2013). The researcher perceives that cultural values, beliefs and attitudes influence SME owner’s conflict management style. Apart from cultural influence, the researcher intends to explore the impact of the process of acculturation (the cultural adaptation of foreigners) on conflict management in Chinese and Indian immigrant-owned SMEs in Auckland metropolitan. The approach would be to select Chinese and Indian immigrant SME owners residing in Auckland metropolitan region for over five years. The researcher will interview them to identify if acculturation (cultural adaptation) has influenced their conflict management style.

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  • The ability of two internal clock models to predict performance on a temporal bisection procedure

    Wiles, Lisa Maree (2015)

    Masters thesis
    University of Waikato

    This research is a replication of Machado and Keen’s (1999) procedure which tested the ability of two competing models of animal timing; Learning to Time (LET) and Scalar Expectancy Theory (SET), to predict pigeons performance on a temporal bisection task. Hens were trained in two temporal discrimination's; in Type 1 trials they learned to choose a red key after a 1-s signal and a green key after a 4-s signal and in Type 2 trials they learned to choose a green key after a 4-s signal, and a yellow key after a 16-s signal to receive access to reinforcement. After they learnt these discriminations, intermediate durations were presented. The resulting psychometric function did not superpose, violating the scalar property of timing. When novel key and duration combinations were presented, performance on subsequent generalisation tests closely matched LET’s predictions. Overall, the results support the findings of Machado and Keen (1999) and supported LET’s rather than SET’s predictions.

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  • An exploration of Māori cultural values and how they are expressed in modern Māori whānau in relation to food

    Beavis, Brittani Sakkara (2017)

    Masters thesis
    University of Otago

    Whakapapa (Background) Māori are the indigenous people of Aotearoa, comprising 15% of the New Zealand population. Māori believe health is multifactorial, and if one aspect of health falters then the others will be affected. Therefore, health professionals need an applied and practical understanding of Māori cultural values. This understanding and awareness will allow them to provide a more appropriate and effective service for Māori whānau (family). Objective In this research, thematic qualitative methodology will be used to explore the expression of Māori cultural values within modern Māori whānau in relation to food. Specifically, this research will attempt to address these aims: 1. Identify Māori values that could influence healthy eating in Māori households 2. Explore how these values are expressed in modern Māori households 3. Discuss the practical implications for not only myself, but all dietitians, when working with Māori. Ngā Tapuae (Methods) Using academic and grey literature, and Kaupapa Māori Theory, four core cultural values were identified: 1) Manaakitanga (to support one another), 2) Kaitiakitanga (guardianship of the land), 3) Taonga Tuku Iho (passing down of knowledge), and 4) Kia pike ake i ngā raruraru o te kāinga (to lift the household up from hardships). These thematic codes were used to analyse, using a strengths-based approach, the extensive textual data from four Māori households and two Māori field researchers who took part in the 2011 “Out of the Box” study. Ngā Hua (Results) Within four Māori households, as well as two Māori researchers, the four traditional cultural values were clearly expressed. Manaakitanga was the most commonly expressed value which encompassed aroha (love), whānau, and koha (gifting). Whānau placed a lot of emphasis on showing manaakitanga especially around tamariki (children), to ensure they instilled this important value in the children. Manaakitanga was important to whānau as it had many positive effects on Hauora Māori (Māori health), such as providing a sense of wellbeing and belonging and improving emotional health. Taonga Tuku Iho was the next most commonly expressed value, with whānau putting an emphasis on ensuring their tamariki learnt basic food and healthy eating principles. Kaitiakitanga was expressed but to a much lesser extent due to tenancy agreements preventing whānau from having a garden. However, there was still a strong belief that food was not to be wasted and thus excess kai (food) would be gifted to prevent wastage. Lastly, kia piki ake i ngā raruraru o te kāinga was most clearly expressed within the low-income whānau, where the mother had to overcome financial hardships and show resilience to provide her whānau with a healthy diet. Mutunga (Conclusion) This research showed that four traditional Māori cultural values related to food were expressed within participating modern Māori whānau, and positively influenced Hauora Māori outcomes. Dietitians and other health professionals need to be aware of these values and how they influence healthy eating in order to maximise Hauora Māori outcomes for all Māori whānau.

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  • Materialising Ancestral Madang: Aspects of pre-colonial production and exchange on the northeast coast of New Guinea

    Gaffney, Dylan (2017)

    Masters thesis
    University of Otago

    This thesis examines the nature of changing pottery production and exchange on the northeast coast of New Guinea in the pre-colonial past. Models in Melanesian archaeology suggest that the recent past, leading up to ethnographic contact, was a dynamic period of changing mobility, social interaction, and technology, and is crucial to our understanding of culture in the region today. Here, this important time of social and technological flux is investigated by examining the emergence of the extensive Madang (Bilbil/Bilibili) exchange network. This network was based around the specialised production and distribution of ‘Madang-style’ ceramics—a distinctive red-slipped, applied/incised tradition that has previously been found from Karkar Island in the north, to the New Guinea Highlands in the south, and the Bismarck Archipelago to the east. The major contributions of this thesis describe the recent survey, excavations, and analyses of Madang-style ceramic assemblages from the Madang coast: at Tilu, Malmal Village, and at Nunguri, on Bilbil Island. This analysis takes a technological approach to ceramics, following the chaîne opératoire, which can systematically examine the nature of production and exchange, and delineate past production groups working within broader communities of practice. In this way, the complete production and distribution sequence of the Madang-style is examined through a variety of traditional and geochemical techniques. Consideration is then given to the implications of these results to processes of production and exchange along the northeast coast generally, and to important, unanswered questions in Madang’s culture history.

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