6,227 results for Otago University Research Archive

  • The transferability of modern medical laboratory technology to Fiji

    Ranadi, Vilomena (2017)

    Masters thesis
    University of Otago

    Medical technology has improved the health status of the population in developed countries. This has influenced the progress from intuitive medicine to precision medicine through the use of imaging, molecular biology and other diagnostic approaches that specifically identify the causes of disease. Such technology is not readily available in third world countries and as such medical technology transfer is crucial in developing nations, although this is a relatively complex process. The aim of this study is to investigate the requirement, appropriateness, management, as well as the estimated cost for establishing selected advanced diagnostic techniques at the Colonial War Memorial Hospital (CWMH), Suva, Fiji. The study investigates the presence of carbapenemase resistance in extended spectrum beta lactamase (ESBL) septicaemia in Fiji in order to establish the need for the introduction of the CARBA NP; a rapid diagnostic tool for detecting carbapenemase resistant microorganisms. The study also examines current Histology and immunohistochemistry practises as well as the test assays utilized at CWMH. In particular, the study focusses upon laboratory processes that could be updated in order to promote conclusive pathological diagnosis, especially for breast cancer and lymphoma. Lastly, establishment costs and management strategies to support the transfer of these tools are examined. A mixed method approach, involving qualitative and quantitative research techniques, was undertaken to assess and analyse the current status of testing. Studies were also undertaken to provide evidence for the desirability of introducing the technologies based upon a perceived need, as well as fiscal aspects relating to establishment costs and on-going management expenses. Information was gathered through the examination of hospital records, interviews with strategic personnel and through laboratory attachments. Based on the results of the study, carbapenemase resistance was not detected in the ESBL septicaemia cases that were examined. However, it was revealed that 34.7% of these cases were treated with Meropenum (carbapenemase) which is known to promote the emergence of carbapenemase resistant micro-organisms if used inappropriately. In addition, 59.2% of ESBL septicaemia was acquired on the nineteenth day of admission, which reflects an apparent problem with infection control. Examination of the Histology and immunohistochemistry practises at CWMH showed that in many instances, standardised protocols were not followed. Analysis provided evidence as to the high level of breast carcinoma and lymphoma cases submitted to the laboratory for diagnosis. Of cases submitted, 40.3% were breast specimens, with 87.4% of these having a malignant diagnosis. Adequacy of pre-analytical fixation was observed in only 14% of modified radical mastectomy specimens. Additionally, 59.4% of breast cancers were ER/PR positive, while 26.7% were both ER and PR negative. The study also showed that 45.6% of breast cancers occurred in women below the age of 50 years. In view of the number of ER/PR negative cases - of which an unknown number were triple negative breast cancers - it was concluded that there is a need for establishing HER2 antibody testing in Fiji. Lymphoma was diagnosed in 15.4% of cases submitted to the laboratory. Of these 61.8% were in male patients, with extra-nodal lymphoma being seen in more than 50% of cases. Bcl2, CD10 and Ki67 antibodies were identified as being important modalities that could be introduced to assist in lymphoma diagnosis. It was further determined that the establishment costs and maintenance of these diagnostic tools was acceptable. In conclusion, this study has demonstrated that there is need to transfer the identified diagnostic tests to bridge the diagnostic gaps at the CWMH laboratory. It was also shown that significant advances in patient management would be achieved through the introduction of the diagnostic tests highlighted in this study.

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  • Locating “I think, therefore I am” in the Meditations

    Pensler, Samuel (2017)

    Masters thesis
    University of Otago

    “I think, therefore I am” (Cogito, ergo sum) suggests a “naïve” interpretation whereby anyone who argues as follows is certain of their existence. I think. Therefore, I am. Curiously, the famous line doesn’t appear in the Meditations, while it does in Descartes’ other works. Does the naïve interpretation, while a plausible reading of the other works, misread the Meditations? In this thesis, I claim that the Meditations should be naïvely interpreted by defending this position against three central objections. Objection 1: Nowhere in the Meditations does the meditator assert that cogito is certain. I respond that the meditator does assert the certainty of cogito in the first meditation as he doubts his beliefs. This happens when he makes judgments about what he is thinking such as: “I have no answer to these [skeptical] arguments” and “my habitual opinions keep coming back.” Objection 2: Even if the meditator claims cogito in the Meditations, he never accounts for why cogito is certain, which he must do if he uses it as a premise. I show that an argument for the certainty of cogito can be reconstructed by examining how the meditator doubts his beliefs. The idea behind the argument is that for the meditator to doubt his belief system it’s necessary that he is certain that he thinks, in particular, that he is certain about what his beliefs are and their amenability to doubt. In short, the certainty of cogito is built into the method of doubt. Objection 3: The naïve interpretation of the Meditations is false since Descartes says that the cogito is not an argument. For, he says that the cogito is a “simple intuition of the mind”, not a “deduction by means of syllogism.” I respond that Descartes is not denying that the cogito is an argument. He is specifying the type of reasoning process one must use to work through the argument from cogito to sum—sum is discovered by “intuition” rather than syllogistic reasoning.

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  • Electroencephalographic Measures of Depressivity: Alpha Asymmetry and Fractal Dimension

    Kawe, Tame Ngahiwi James (2017)

    Masters thesis
    University of Otago

    Recent research has suggested that neurofeedback, utilising alpha asymmetry or fractal dimension as an index of depression, may be an effective treatment for depressed individuals. In this thesis the relationships between frontal alpha asymmetry (FAA), parietal alpha asymmetry (PAA) and Higuchi’s fractal dimension (HFD) with PID-5 depressivity were investigated to assess their potential as signals for neurofeedback. Resting EEG previously recorded from a general sample of 66 individuals was analysed. The data of male and female participants was analysed separately. Optimised eye condition and bandwidth were determined with one way, repeated measure ANOVAs. Optimal specific measures of FAA, PAA and HFD were then identified by the proportion of PID-5 depressivity accounted for. The optimal FAA measure was obtained from the frontopolar electrode pair (Fp2 – Fp1) in the 10-12Hz sub-band. It was the only measure that was reliable in both male and female participants. PAA between the lateral electrode pair (P8 – P7) in the 8-10hz sub-band reliably correlated with depressivity in female, but not male, participants. HFD was reliable at every electrode in female, but not male, participants and displayed intercorrelation between all electrodes in both genders. A combined model using all three optimal measures showed that the proportional variance of FAA, PAA and HFD was mainly additive, with little variance shared between measures. The results suggest that FAA at the frontopolar electrode pair (Fp2 – Fp1) in the 10 – 12Hz band may be the optimal AA measure for neurofeedback protocols targeting depression. Correlations between AA and depressivity were often site- and band-specific; reliable correlations observed in one location did not necessarily generalise to other locations. Correlations between HFD and depressivity were not site-specific with most variance shared between sites. There was little overlap between the variance accounted for by FAA, PAA and HFD; indicating that the information conveyed by each is due to distinct neural processes, which may be associated with distinct aspects of depressivity and, potentially, other trait measures. Future work should assess replicability and the extent to which the results are specific to depressivity.

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  • A Stand-Alone 'Self-Locking' Laser

    Cowdell, Carolyn (2017)

    Masters thesis
    University of Otago

    This dissertation presents a stand-alone ’self-locking’ laser. The aim of the project was to develop a prototype of a ’self -locking’ laser that requires no user input, other than to turn the laser on. The prototype was developed to be used as a repump laser for laser cooling experiments; however, its design is aimed at a market of individuals who do not have the background skills required to lock a laser. The project uses a frequency modulated spectroscopy setup to obtain the sub-Doppler atomic spectrum of Rubidium, which is demodulated to obtain zero-crossing linear slopes at the exact points of each atomic transition and crossover transition. The frequency modulation for the spectroscopy setup, the signal analysis, as well as the automatic locking and re-locking of the laser is all implemented digitally using an Arduino open source microcontroller. The distributed feedback laser used for the design is fully characterized and the lock of the ’self-locking’ laser is analyzed in detail. The finished prototype has been used in a laser cooling experiment as the repump beam to investigate how it performs under real experimental conditions.

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  • Coherent Frequency Conversion from Microwave to Optical Fields in an Erbium Doped Y2SiO5 Crystal: Towards the Single Photon Regime

    Fernandez Gonzalvo, Xavier (2017)

    Doctoral thesis
    University of Otago

    In the context of quantum information technologies superconducting qubits (SQs) are very attractive devices for the manipulation of quantum states, and present themselves as one of our best candidates to build a quantum processor. They couple naturally to microwave photons, for which suitable quantum memories or a long distance propagation channel don’t exist. A way around these limitations is to turn these microwave photons into optical ones by building a quantum frequency converter: a device by which the frequency of a photon can be changed while preserving its non-classical correlations. Then, optical fibres could be used to link distant SQ-based devices together, facilitating the creation of a network of quantum computers. Moreover, SQs could then be coupled to quantum memories compatible with photons at optical frequencies, which are the most well developed kind of quantum memories at the present time. This thesis explores the possibility to convert single microwave photons into optical photons using erbium doped in a yttrium orthosilicate crystal (Er3+:Y2SiO5). Er3+:Y2SiO5 is a good candidate because it has a naturally occurring optical transition near 1536 nm close to the point where silica optical fibres show their minimum loss. A microwave transition can be found in two different ways: one way is to use the 167 isotope of erbium, which is the only stable isotope that shows hyperfine splitting as it has non-zero nuclear spin. The hyperfine structure of the ground state of 167Er3+:Y2SiO5 spans over about 5 GHz. The other possibility is to use the other stable isotopes of erbium and Zeeman split their ground state using an external magnetic field. A microwave transition near 5 GHz can be achieved with moderate magnetic fields due to the high ?-factors of Er3+:Y2SiO5. The physical process of interest is a three wave mixing process involving two fields at optical frequencies and one field at microwave frequencies. In order to boost the efficiency of the frequency conversion process the Er3+:Y2SiO5 crystal is placed inside a microwave and an optical resonator. The problem is first explored from the theoretical point of view, where a nonlinear coefficient Λ(2) is derived (analogous to the ?(2) often used in nonlinear optics), and the interaction between cavity modes and the nonlinear medium is studied. It is predicted that with a sample cooled down to millikelvin temperatures total frequency conversion between microwave and optical fields can be achieved. A preliminary hole burning spectroscopy experiment is performed with the objective of reconstructing the hyperfine structure of the excited state of 167Er3+:Y2SiO5, but the complexity of the problem makes it too difficult to achieve this goal. Then a series of experiments are shown, aimed at determining whether or not frequency conversion at the single photon level is achievable using the even isotopes of erbium in a magnetic field. These experiments are based in the Raman heterodyne spectroscopy technique, which is used in combination with electron paramagnetic resonance and optical absorption spectroscopy. In all experiments the sample is cooled down to cryogenic temperatures near 4 K. A first experiment shows that the frequency conversion process exists in Er3+:Y2SiO5, in a setup where only a microwave resonator is used, but not an optical one. A second experiment is performed in a similar setup, this time presenting a quantitative study of the properties of the frequency conversion process, and its comparison with the theoretical model previously derived. A third experiment is performed, which incorporates an optical cavity to the system. The interaction between the erbium ions and the optical cavity introduces a whole new range of experimental complications, which are studied and discussed. Then, the frequency conversion signal is studied anew, showing an unexpected highly non-linear scaling behaviour with the input powers. A hypothesis explaining this unexpected behaviour is given, referring to stray optical absorption in the inhomogeneous line of Er3+:Y2SiO5 (and in particular 167Er3+:Y2SiO5), which can be bleached out under certain circumstances due to spectral hole burning effects. The overall maximum frequency conversion efficiency observed is of 3 × 10^−4 per Watt of pump laser power. While this value is still far from the target several ways of improvement are proposed, including cooling down the system to millikelvin temperatures, increasing the dopant concentration and modifying the geometry of the resonators.

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  • The Chemokine-binding Proteins Encoded by Bovine Papular Stomatitis Virus and Parapoxvirus of Red Deer in New Zealand: Molecular and Functional Characterization

    Sharif, Saeed (2017)

    Doctoral thesis
    University of Otago

    Poxviruses are large DNA viruses that infect a wide range of animals including humans. During the course of evolution, these complex viruses have gained an extensive repertoire of immunomodulatory genes to evade host immune responses in order to enhance their own survival. One of these immunomodulators is a secreted soluble chemokine-binding protein (CBP) which has no known mammalian homologue. Chemokines are a large family of chemotactic proteins that regulate recruitment of leukocytes to sites of infection or inflammation, as well as homeostatic migration of leukocytes through lymphoid organs. Members of the chemokine family are classified as CXC, CC, C and CX3C based on the arrangement of cysteine residues at the N terminus. The majority of the known chemokines fall into either the CXC or the CC classes. In general, CXC chemokines are potent chemoattractants of neutrophils or lymphocytes, whereas CC chemokines are chemoattractants for monocytes. The CBP genes have been identified in Orthopoxviruses and Leporipoxviruses, as well as Parapoxviruses (PPVs) that includes Orf virus (ORFV), and genes encoding putative CBPs have been identified in Pseudocowpox virus (PCPV), Bovine papular stomatitis virus (BPSV) and Parapoxvirus of red deer in New Zealand (PVNZ). Previous studies have demonstrated the structural and functional activity of ORFV-CBP, however, there is little known about the CBPs of the other PPVs. This study describes the characterization of CBPs secreted by two less-studied members of the PPVs; BPSV and PVNZ. BPSV and PVNZ infect cattle and red deer, respectively, and induce superficial pustular skin lesions and lesions of the oral mucosa. Further PVNZ infects the velvet of antlers. In the case of BPSV infections, the immunity is short lived, a phenomenon that could be related to the immunomodulators encodes by the virus. In chapter two, the molecular properties of BPSV and PVNZ CBPs are described. Mass spectrometry revealed that the BPSV-CBP is a homodimeric polypeptide with a MW of 82.4 kDa, and sequence analysis showed around 40% identity and 70% similarity between the CBPs of BPSV and ORFV at the amino acid level. Moreover, structural modelling based on the crystal structure of the orf virus CBP, predicted a similar beta-sheet sandwich for both proteins, suggesting that like ORFV-CBP, BPSV-CBP may have broad-spectrum chemokine binding properties. PVNZ, unlike other PPVs, express three distinct CBPs (namely 112.0, 112.3 and 112.6). The CBPs of PVNZ112.0 and PVNZ112.3 have 46% identity and cluster together, while PVNZ112.6-CBP has only about 30% identify with the other PPV-CBPs and falls into a separate branch of phylogenetic tree. It seems that multiple PVNZ-CBPs have arisen by a process of duplication and divergence from a common ancestral gene. Although sequence analysis of the PVNZ-CBPs showed a moderate degree of identity (30-40%) with the ORFV-CBP, it predicted a conserved structural core for PVNZ-CBPs, suggesting a certain chemokine-binding activity for these viral proteins. Chapter three describes a comprehensive chemokine-binding screen of BPSV-CBP and the PVNZ-CBPs by surface plasmon resonance (SPR) assay. The SPR results showed high-affinity binding of the BPSV-CBP to a wide-range of inflammatory murine chemokines within the CXC, CC and XC classes. Murine cells and mice were used in subsequent studies to characterise the in vitro and in vivo functions of BPSV-CBP. The SPR assay also revealed that each PVNZ-CBP has a unique chemokine-binding profile. In general, PVNZ-CBP 112.3 binds to CXC chemokines selectively, while PVNZ-CBP 112.6 has strong binding affinity with CC chemokines. Remarkably, PVNZ-CBP 112.0 had no or weak binding against most of the chemokines tested. The spectrum of the inflammatory chemokines targeted by the CBPs of BPSV and PVNZ suggest that like orf virus, these Parapoxviruses target inflammation as a strategy to subvert immune cell activation and recruitment to infected tissue. In chapter four, murine neutrophils and monocytes were used in transwell migration assays to investigate the in vitro effects of BPSV-CBP on chemokine-induced chemotaxis. Mature neutrophils were differentiated from a mouse promyelocytic (MPRO) cell line and shown as Ly-6Ghi CD11bhi cells that express the chemokine receptor CXCR2. After optimizing the neutrophil migration in response to CXCL1, CXCL2, and CCL3 chemokines, the BPSV-CBP was shown to cause a significant reduction in cell migration at a molar ratio of chemokine-to-CBP of 1:4, 1:1 and 1:1 respectively. Moreover using monocytes derived from mouse bone marrow cells cultured in the presence of M-CSF, and characterized as CD115+ CD11b+ Gr-1+ cells, BPSV-CBP potently inhibited their migration towards skin-related inflammatory chemokines CC2, CCL3, and CCL5 at the molar ratio of chemokine-to-CBP of 1:1, 1:1, and 1:0.5, respectively. Finally, a lipopolysaccharide (LPS)-induced murine inflammatory skin model was applied to evaluate the in vivo impact of the BPSV-CBP. Histological examination, in conjunction with a myeloperoxidase (MPO) assay of skin samples, revealed that intradermal injection of the BPSV-CBP reduced the influx of neutrophils (Gr-1+ MHC-II+) into the inflamed sites at 12 h post LPS injection. Moreover, the BPSV-CBP reduced infiltration of MHC-II+ monocyte/dendritic cells into inflamed skin. Overall, this study showed that the BPSV-CBP is an antagonist for a wide range of chemokines, and can inhibit the migration of inflammatory immune cells both in vitro and in vivo. These findings suggest that the CBP could be important in virulence and pathogenesis of BPSV infections. Importantly, the broad binding properties of the CBPs suggest that they may have therapeutic value as anti-inflammatory drugs.

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  • N cycling and microbial dynamics in pasture soils

    Samad, Md Sainur (2017)

    Doctoral thesis
    University of Otago

    Pasture soils are a significant source of the greenhouse gas, nitrous oxide (N2O) and as such they contribute to global warming. It has been reported that N2O is approx. 300 times more potent than carbon dioxide (CO2) as a greenhouse gas. Thus, understanding the mechanisms for controlling N2O emissions from soil is key to developing new soil management strategies to counter or prevent climate change throughout the world. Despite this, very little is known about the key regulators of production and consumption of N2O in pasture soils, especially under urine patch conditions. To address this, we used pasture soils representing both Northern (Ireland) and Southern (New Zealand) Hemispheres in experiments designed to understand both phenotypic and genotypic characteristics associated with N2O emissions. We used a combination of gas kinetics, soil physicochemical characterization, metagenomics, 16S amplicon sequencing and quantitative PCR (of denitrifier: nirS, nirK, nosZI and nosZII; and nitrifier: bacterial and archaeal amoA genes) to link physical, chemical and biological parameters associated with emissions. This thesis work was able to show how in nitrate-amended pasture soils the rate of carbon mineralization under oxic and anoxic conditions is positively linked to the rate of denitrification. In addition, the emission ratio of N2O is negatively linked to pH. Both pH and N2O emission ratio were significantly associated with 16S microbial community composition as well as microbial richness. This result confirms that pH imposes a general selective pressure on the entire community and that this is associated with changes in emission potentials. This supports the general ecological hypothesis that with increased microbial diversity, efficiency of N2 production increases (i.e. more efficient conversation of N2O to N2). Worked performed in a simulated urine patch (oxic conditions) suggested other pathway (e.g., nitrifier-denitrification) as a source of N2O emissions. No clear trend was observed between emission ratio of N2O under urine patch condition and emission ratio under true denitrification conditions (i.e. under anoxic environment). The urine patch accelerated the rate of C mineralization about 10 times, concurrent with a decrease in prokaryotic richness and a shift in community composition. Community response identified two major groups of responders: negatively affected prokaryotes we hypothesized utilized energy from N-linked redox reaction for maintenance and positively responding populations that use this energy for growth. Overall, this study provides new insights into the N2O emissions and microbial dynamics for reduction of N2O in pasture soils.

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  • Investigating and Enhancing Willingness to Communicate and Motivational Self-System of Yemeni Rural EFL Learners

    Al-Murtadha, Mutahar Ahmed (2017)

    Doctoral thesis
    University of Otago

    A major problem in second language (L2) learning and teaching is learners’ low willingness to communicate (WTC). WTC refers to the extent to which an individual is ready to initiate communication with others. Some L2 researchers have argued that enhancing L2 WTC should be the fundamental goal of the L2 learning process. However, although previous studies have identified some factors that influence WTC, most, if not all, did not go beyond exploring the factors to promoting WTC through interventions. This thesis has two main aims: to understand the factors that influence the WTC of Yemeni rural secondary school English students and to promote their WTC based on understanding the factors that influence it. These two aims were achieved in a mixed methods project of four studies in which the factors influencing WTC were first identified in three studies, and then based on those factors, an intervention program to enhance students’ WTC was conducted in a fourth study. The first study used a large survey of 564 students. Quantitative data analysis indicated that L2 WTC inside the classroom was predicted by L1 WTC, ideal L2 self, L2 learning experience, L2 intended learning effort, and gender. Study two was an observational study of twelve students who had participated in study one. Data were collected through weekly classroom observations in L1 and L2 classrooms. Quantitative data analysis confirmed the significant relationship between L1 and L2 WTC found in study one and revealed significant gender difference in L2 observed WTC, with males demonstrating higher WTC. However, no significant relationship between self-reported WTC and observed WTC was found in both L1 and L2. The self, learning experience, and learning effort appeared to influence students’ observed WTC. Study three focused on students’ perceptions of their L2 WTC inside the classroom. It involved the same students from study two, but data were collected through interviews and weekly journals. Qualitative data analysis revealed three types of factors that influenced WTC: contextual, affective, and cognitive. The ideal self most influenced WTC through the mediation of topics related to students’ future careers. Study four was an intervention that promoted WTC and its four predictors–ideal self, learning experience, learning effort, and linguistic self-confidence–over a six-week period. Two-hundred six students were assigned to either an experimental group (N= 104) or a control group (N = 102). The experimental group received one forty-five minute visualization and goal-setting lesson a week, whereas the control group received a regular lesson. Quantitative and qualitative data analysis indicated that the intervention enhanced WTC and its predictors. The thesis concludes with three contributions. Theoretically, it shows that WTC can be influenced by the ideal self, learning experience, intended learning effort, and gender. Methodologically, it shows that mixed methods research leads to a deeper understanding of WTC and how to promote it. Pedagogically, the intervention practically shows English teachers how visualization and goal-setting activities can enhance students’ WTC and its predictors.

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  • The algorithmic subject: the neo-liberal apparatus and the social media technology of power.

    Hacon, Christopher Laurence (2017)

    Doctoral thesis
    University of Otago

    This thesis is a Foucauldian inspired apparatus investigation that contributes to our understanding of neo-liberalism. The thesis will show that neo-liberalism has varied and, at times, contradictory relationships with social media platforms. The investigation is predominantly conducted through an interrogation of the academic literature and deals with the problem of how to grasp the neo-liberal present. I focus upon Foucault’s important account of subjectivity, and consider, firstly, how this account might work in relation to neoliberalism’s dominant mechanisms, and, secondly, how this subjectivity works in the context of theorisations of social media platforms. The introduction lays out this terrain and the matrix through which I approach the objects of my investigation. Part 1 of this thesis engages with the various proponents and critics of neo-liberalism and the contribution that Foucault’s The Birth of Biopolitics lectures have made. The second part moves to identify and articulate six dominant mechanisms of the neo-liberal apparatus. These include: freedom, individualism, competition, financialization, adaptation, and accumulation. I also present a genealogy of the social media technology of power and argue that these objects are engaged in producing the neo-liberal and algorithmic subject respectively. Finally, Part 3 of the thesis explores the relationships between these objects and argues that it is too simplistic to present the dominant social media platforms as merely a product of a neo-liberal apparatus. Although neo-liberalism and social media are in a state of synergy, they are also, and more importantly, in tension with one another. The thesis thus makes the following contributions to critical work in communication, media and politics: my mapping of six dominant mechanisms which make the neo-liberal apparatus work; the articulation of the subjectivity produced by this broad machinic apparatus in relation to social media technology of power; my identification of the tensions and synergies between the neo-liberal apparatus and social media technology of power.

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  • Pricing for profit in dynamic competitive markets using logit demand models: closed form optima and some corollaries

    Mather, Damien William (2017-09-11)

    Working or discussion paper
    University of Otago

    This manuscript develops and simplifies a pricing decision model for maximum profit as a function of unit variable cost, 3 estimated price-demand response points, a simplified representation of known competitor intensity and dynamic pricing behaviour and typically known down-channel demanded mark-ups that uses a logit price-demand response model. Including a logit price-demand response model supports pricing decisions that simultaneously optimise both net profit, and Gross Marginal Return On Investment or GMROI. Differential calculus methods are used to produce a simplified function to optimise profitability. Worked examples demonstrate the ease of use and practical usefulness of such supported pricing decisions in typical decision making contexts using conventional decision making aids. Pilot surveys of pricing decision makers indicated two qualitatively different decision making processes, only one of which is near optimal. This method adapts to a range of logit price-demand response model complexity from a simple primary category demand response capturing a pricing decision-maker’s response expectations to more complex alternative-specific-coefficient multinomial logit models fitted to scanner panel revealed preference or stated preference survey data. The model also adapts across channel depth from direct manufacturer sales to many channel members. Market simulations using typical brand equity, price elasticity, competitor intensity and dynamic pricing response heuristics delivers informative insights that somewhat contradict more established market pricing axioms and interpretations

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  • A Macro View on Tourists' Emotional Experiences

    Rahmani, Kamal (2017)

    Doctoral thesis
    University of Otago

    The study aims to explore tourists’ emotional experiences as a process, from an objective perspective. Experience as a subjective-objective phenomenon between the tourist and the world comes from a direct encounter with the environment, places and people. This direct sensory meeting then, through sensory impression of the destination, provokes internal emotional reactions. This perceptual process in tourists’ emotional experiences can be summarized in three steps: (1) stimulus exposure; (2) affective reactions; and (3) meaning-making. This, in turn, triggers different states of well-being, including hedonia and eudaimonia. The research employs Plutchik’s basic emotions model (Plutchik, 1980), Osgood’s semantic differential model (Osgood, Suci, & Tannenbaum, 1957), and self-determination theory (SDT) (R. M. Ryan & Deci, 2000) to represent affective reactions, meaning-making, and eudaimonia, respectively. We divide the study into three sub-studies: the first study explores methodology, the second study explores relationships between affective reactions (step two) and meaning-making (step three), and the third study explores the relationships between meaning-making (step three) and well-being (consequences of experiences). Despite a general agreement among scholars on the nature of the tourism experience being complex, intersubjective, and multi-faceted, there is little research to address the methodological issues in this area. The first contribution of this thesis is towards an analytical methodology, which applies Web 2.0 and Corpus Linguistics (CL) in the study of tourism experience, as a way forward to explore and test theories. The study firstly seeks to understand the participation of tourists on Web 2.0. With the growing usage of Web 2.0 and tourists’ tendency to document their experiences, there are huge amounts of data available online. CL then helps extract knowledge from the documents that tourists have produced after their experiences. The second and the third studies then, apply the methodology to study tourists’ emotional experiences. The results provide objective insight into the process of tourists’ emotional experiences across several destination countries; New Zealand, France and a global sample that is comprised of 10 countries together. The findings show how holiday tourism exhibits unequal balances of positive and negative emotions. Management of both positive and negative experiences will, therefore, provide a better overall experience. The study provides directions towards improving experiences within and between modes of meanings. Moreover, the study encourages the development of emotion-based destination scales. The results generalise the differences between hedonia and eudaimonia across samples depending on the meaning-making step. They also demonstrate the experiences with the highest and lowest levels of well-being and ill-being.

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  • Barriers to the Development and Implementation of Assistive Gaming Technology for Upper-Limb Rehabilitation After Acquired Brain Injury: Stakeholder Perspectives.

    Flint, Kirsten Louise (2017)

    Masters thesis
    University of Otago

    Acquired brain injuries are one of the leading causes of lasting physical disability worldwide. Current rehabilitation services are insufficient, and an increasingly aging population suggests that this problem will only intensify. Gaming technology has recently shown promise in being able to augment the rehabilitation process, however this technology has not received widespread support from those involved in clinical practice. This Masters thesis attempts to identify the barriers hindering the development and acceptance of gaming technology in the current healthcare system. The results of the research undertaken inform both the written academic component of this thesis and the creative component, the documentary film Mind Games. For both components of the thesis, a range of stakeholders involved in the research, development and the implementation of assistive gaming technology for rehabilitation after stroke were interviewed using semi-structured interview techniques. Some of these interviews were utilised to create Mind Games and some informed the academic component. Their answers were coded thematically and qualitatively analysed for ideas relating to barriers which prevented the development and adoption of assistive gaming technology. Barriers identified ranged from those tangible in nature, to more abstract and complex ones and fell into five main categories: technological and design based barriers, barriers stemming from the healthcare system’s need for trials and evidence, barriers which stem from institutional patterns and processes, barriers involving investments, economics and funding, and barriers inherent in the introduction of new and innovative ideas into complex organisations and systems. This research concludes with suggestions as to how to begin to overcome these barriers and improve rehabilitation services.

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  • Dissolution of Abiogenic and Biogenic Calcium Carbonate under Ocean Acidification Conditions

    Adhami, Zhaleh (2017)

    Doctoral thesis
    University of Otago

    Under ocean acidification conditions, the chemistry of the seawater will change including a decrease in pH, a decrease in carbonate ion concentration and a decrease in the calcium carbonate saturation state of the water (Ω). This has implications for solid marine calcium carbonates including calcifying organisms and carbonate sediments. The dissolution kinetics of marine carbonates are poorly understood, therefore modelling of the future ocean under ocean acidification scenarios is hampered. The goal of this research was to provide an increased understanding of the kinetics of marine carbonate dissolution, including dependence of the dissolution rate of calcium carbonate mineral phases (calcite, calcite-aragonite, low Mg-calcite) on conditions relevant to ocean acidification, and then to apply this to biogenic samples (Pāua, kina and oyster). The effects of saturation state (Ω), surface area, and temperature were studied. Two methods were refined and used to collect and analyze the dissolution data – a pH-stat method and a pH free-drift method, with manipulation of the carbonate chemistry by addition of NaHCO3 and HCl. A LabVIEW® based program was developed for instrument control and automation and for data acquisition. The empirical equation R = k(1-Ω)n, was used to determine the reaction rates (R), the rate constants (k) and the reaction orders (n) for the each of the mineral phases and shellfish species. For the pH-stat method, the dissolved mass of carbonate was calculated from HCl consumption; in an open cell configuration the CO2 produced in the dissolution reaction is vented to the atmosphere and any change in pH or alkalinity due to dissolution is restored by acid addition and there is no change in CT (the dissolved inorganic concentration. However, in a closed cell configuration where there is no venting, the calculation procedure must take into account the change in CT, and requires a “correction factor”, (d(CT)/d(HCl)), which is dependent on the initial CT and AT at each stage of the dissolution reaction. For the pH free-drift method, a numerical simulation technique was developed for easy and accurate estimation of the carbonate concentration at each step in the dissolution reaction. These chemistry based methods were applied on short time scale experiments (time frames of minutes), which had the advantage of making this work independent of the commonly applied CO2 bubbling method usually used to maintain a constant pCO2 and the application of highly stable electrodes necessary for long scale runs. The results from the pH-stat and pH free-drift methods are not significantly different, and even close to equilibrium conditions (Ω=1), the dissolution rate determined using the pH free-drift method had an accuracy similar to that of the pH-stat method. For abiogenic calcium carbonate, Iceland spar showed a higher dissolution rate in artificial seawater compared with marble at the same value of Ω. For crushed marble, the dissolution rate constant increases in accordance with a rise in temperature, and a high apparent activation energy for the dissolution reaction was calculated (37.6 kJ mol-1) using the Arrhenius equation (K=Ae-Ea/(RT)), which indicated that dissolution was dominated by surface controlled processes. The dissolution rate of both crushed and cubic samples decreased with increasing saturation state, and as the loading mass of calcite (a proxy for surface area) increased, the dissolution rate increased. Different reaction orders were obtained in different ranges of saturation state, and this is attributed to the presence of different reaction mechanisms. The history of the sample influenced the dissolution rate, indicating that the kinetics of dissolution depends not only on the chemistry of the solution but also on the surface characteristics of each sample over time. The study of the dissolution rates of biogenic carbonates focused on three species of particular economic and cultural value to New Zealand. Kina (Sea-urchin - Evechinus Chloroticus) have spines composed of low magnesium calcite; Pāua (New Zealand abalone - Haliotis Iris) have bi-mineral shells made of calcite and aragonite, and Oyster (Tiostrea chilensis) shell is primarily calcite. All crushed biogenic samples (oyster, sea-urchin spine and Pāua), owing to their complex microstructure and the higher amount of available active surface area, have higher dissolution rates than the abiogenic carbonate samples (marble and Iceland spar). Pāua shells, containing fractions of fine crystalline aragonite in the calcite structure, dissolved faster than the sea-urchin spines composed of low Mg-calcite. That was because grain microstructure complexity overrode the mineral stability and caused a selective dissolution of the more stable mineral. The pure calcite oyster shell dissolved with a rate between that of Pāua and sea-urchin spines. Marine calcifying species under the impact of ocean acidification have to allocate more energy on shell formation and maintenance processes. This has potential long-term consequences for well-being or survival of some of those species. It has been argued that larval shell growth is solely dependent on seawater saturation state and it effect on the earliest life stages of marine bivalves is the main constriction for successful development into adult populations, and that is one of the most near future threats of ocean acidification to marine organisms. In subantarctic the water off the south east coast of New Zealand, measured Ω Aragonite ranges from 1.9 to 2.6, and Ω Calcite ranges from 3.0 to 4.1. Saturation state values under 3 makes it difficult for juvenile spices to compose hard shell and generally this condition imposes stress on the calcifier marine organisms. The waters off New Zealand’s South Island are expected to experience the impact of ocean acidification from 2040 onwards. Our results provide valuable insight into the dissolution rates of marine organisms under acidified seawater conditions and thus also provide perspective on how these organisms may be influenced by future OA.

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  • Maternity Outcomes and Access following Regulatory Changes for Isotretinoin Prescribing in New Zealand

    McElroy, Jennifer (2017)

    Masters thesis
    University of Otago

    Aims: Oral isotretinoin is an effective treatment for severe acne that is teratogenic. On 1 March 2009 funded access to oral isotretinoin in New Zealand was extended from dermatologist-only to also include prescriptions written by other prescribers where a dermatologist, vocationally registered general practitioner (GP) or nurse practitioner had obtained a Special Authority for this patient and medication. At the time of the change the Pharmaceutical Management Agency (PHARMAC) funded the development of an electronic decision support tool for primary care to support the safe prescribing and use of isotretinoin. Regular review of health outcomes was recommended to ensure the widening of funded access did not have negative effects on the health of the population. This study aimed to examine the previously identified inequitable isotretinoin access to determine if the change in funded prescriber influenced isotretinoin dispensing by ethnicity, age, gender, or deprivation level. The study also investigated terminations of pregnancy (TOPs) and potentially exposed live births following isotretinoin dispensing in women with different prescriber-types and compared these rates in women for whom the prescriber used the Best Practice Advocacy Centre (BPAC) isotretinoin decision support tool to support their prescribing with the rates in women whose prescriber did not. Methods: Retrospective prescription data for the 8 years from 1 March 2007 to 1 March 2015 were analysed to determine how access to isotretinoin changed in the twelve month periods before and after the funding change. Using National Health Index (NHI) codes, maternity outcomes for women who had isotretinoin dispensed during the study period were analysed with regard to TOP and exposed live births. The rates of these adverse maternity outcomes were then compared for different prescriber-types and for women whose clinician used the BPAC decision support tool to guide their prescribing. Results: The use of isotretinoin has continued to increase since the change in funding and people living in more deprived areas (as defined by the NZDep Index), and Maori, Pacific and Asian people have had a proportionally larger increase in numbers accessing isotretinoin. General practitioners (GPs) now prescribe more isotretinoin than dermatologists. The TOP and exposed live birth rate following isotretinoin prescription is similar in women prescribed the drug by dermatologists and GPs. These clinicians prescribe the majority of isotretinoin in New Zealand and the rate of TOP within six months of an isotretinoin prescription is around 16-23% of that for all females aged 15-44 in New Zealand. However the female patients of other clinicians who prescribe isotretinoin much less frequently than dermatologists or GPs have TOPs within six months of isotretinoin at higher rates. Up to 16 live births per year in New Zealand are potentially exposed to isotretinoin with dermatologists, GPs and other clinicians all prescribing for the women involved. Use of the BPAC decision support tool to guide the prescribing of isotretinoin resulted in a lower rate of TOP and exposed births than occurred in patients where it was not used. Conclusions: Isotretinoin is proportionally more accessible to Asian, Maori and Pacific people and people in lower socio-economic groups than it was when funded only through dermatologists. However Europeans and the least deprived groups continue to be the people who use isotretinoin in the greatest numbers. GPs are now the largest group of isotretinoin prescribers in New Zealand but this has not resulted in higher rates of TOP or potentially exposed pregnancies than when prescribing was funded only through dermatologists. However female patients of other prescribers, who do not prescribe isotretinoin as frequently, have higher rates of TOP following isotretinoin dispensing and more potentially exposed live births. The BPAC Decision Support tool helped achieve better maternity outcomes for women accessing isotretinoin where it was used to guide prescribing. The challenge for health managers is to address barriers to its use, to invest in supporting all isotretinoin prescribers to use decision support, and to involve female patients in adhering to contraceptive guidelines.

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  • Blessings and Woes in Luke: Intertextual Echoes of Antithetical Covenant Blessings and Curses in Luke's Gospel with Particular Reference to 6:20b-26

    van den Brink, Julia Remoth (2017)

    Doctoral thesis
    University of Otago

    Luke contrasts his Beatitudes with a corresponding series of Woes creating an antithesis between the eschatological fate of the blessed and those in woe. This antithesis displays similarities to the covenant blessings and curses in Deuteronomy 28. In this thesis, I argue that Luke is framing his Beatitudes and Woes as a series of covenant blessings and curses that serve a similar purpose to that of Deuteronomy 28: to encourage and warn God's people, in the context of a renewed covenant. Consequently, Luke is drawing on a Jewish understanding of blessing and curse as an important feature of the covenant between God and his people. This covenantal background has shaped the presentation of blessing and curse, not only in the Beatitudes and Woes in Luke but throughout the Gospel. I demonstrate this by first examining the Jewish understanding of antithetical covenant blessings and curses, focusing on the multifaceted nature of the covenant and the antithetical nature of blessing and curse, as well as their relation to each other. This relationship between covenant and antithetical blessing and curse is most clearly seen in Deuteronomy 28, which I examine in detail. According to this passage, blessing and curse are part of God's covenant with Israel and are the corporate results of obedience or disobedience to the covenant. However, in later wisdom, prophetic, and Second Temple literature the concept of antithetical covenant blessings and curses developed to include both realised and eschatological circumstantial reversal. In my examination of antithetical covenant blessings and curses in Luke, I approach Luke's narrative as a coherent text. I begin by examining the presence of the themes of covenant and antithetical blessings and curses in the Lukan Infancy Narrative (Luke 1-2). God's covenant and blessings are both present, alongside an expectation that the respective situations of the poor and the rich will be reversed. This circumstantial reversal reappears in Jesus' Sermon at Nazareth (Luke 4:16-30) where Luke's Jesus uses Isaiah 61:1-2 to define his ministry, focusing on the poor and marginalised. This exploration paves the way for the Beatitudes and Woes in Luke 6, where Luke's Jesus begins the Sermon on the Plain with a series of four beatitudes and four woes. The Beatitudes focus on the poor and the persecuted while the Woes focus on the rich and comfortable. They challenge a reading of Deuteronomy 28, where the blessed are always prosperous, and the cursed are always destitute. In Luke, the destitute and faithful are blessed, while the rich are in woe because they have turned away from God, distracted by their riches. Elements of antithetical covenant blessings and curses continue to appear throughout Luke's narrative. At the Last Supper, Luke's Jesus announces that he will be inaugurating the next phase of the covenant between God and his people: the new covenant, alluding to LXX Jeremiah 38:31-34. This Lukan new covenant has a series of blessings and woes in Luke 6:20b-26 that challenges a way of understanding Deuteronomy 28 and encourages obedience to the teaching of Jesus.

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  • Runholding in the Wakatipu Basin 1900-1950

    Scrivener, Ross (2007)

    Masters thesis
    University of Otago

    The pastoral high country, encompassing the tussock-clad hill and mountain lands running down the backbone of the South Island of New Zealand, has since the mid- 1800s been the domain of vast Crown pastoral runs producing most of the nation's fine-wool. The men who held and ran these properties were, and still are, commonly known as runholders. Lake Wakatipu, and the rugged, mountainous land surrounding its shores, forms part of this high country geography. This thesis examines the practice of runholding in the Wakatipu basin between 1900 and 1950. It considers the many inter-relationships between the economic, social, environmental and political aspects of runholding. The history of twentieth century runholding is often viewed dichotomously - of an exploitative, inefficient, and sometimes negligent phase up until the passing of the 1948 Land Act and a more prosperous and sustainable era thereafter. Using various primary archival sources that provide information on over twenty high county stations in the Wakatipu, this thesis explores some of these assumptions. It reveals that runholding was frequently rendered unprofitable through environmental and economic shocks. Throughout the period, the underlying factors of climate, geography and ecology formed the basis ofrunholding's marginality as a form of land use and livelihood. This study shows that while the runs and runholders of the Wakatipu shared many similarities, hardships and successes, there was often considerable variability in the fortunes of different properties.

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  • Rational economic families: social reproduction and social policy in 1980s and 1990s New Zealand

    McMartin, Anna Mary (2017)

    Doctoral thesis
    University of Otago

    This thesis examines social policy during New Zealand’s era of neoliberal transformation, the fourth Labour government of 1984-1990, followed by the fourth National government of 1990-1999. It traces the shift from a protectionist state, which supported a gendered division of paid and unpaid labour, to a neoliberal state, which promoted a genderless paid worker as its citizenship ideal. This shift meant that unpaid work was no longer valorised. Unpaid work lost its former legitimacy as the basis of a claim to financial support from the state (for example, the Domestic Purposes Benefit). These changes gave rise to what is termed the ‘social reproduction dilemma’. This asks: if paid work is the defining activity of the genderless neoliberal citizen, and is an expression of economic rationality, then who ought to do unpaid work and why would they do so? The social reproduction dilemma was influenced by the particular characteristics of New Zealand’s neoliberal reforms: the pace and theoretical purity with which neoliberalisation took place, its commencement by a government of the left, and a relative lack of moral conservatism (although this increased over the course of the National government, particularly as National was joined by a coalition partner, New Zealand First). Although unpaid social reproduction work was no longer supported by the state, the state’s interest in ensuring this work continued, intensifying as the ill effects of reforms, particularly the 1991 benefit cuts, became more entrenched, and social distress became more visible. Labour combined economic liberalisation with a libertarian stance (emphasising personal freedom) on social issues, including feminism, and so was reluctant to suggest that unpaid work was the domain of women. However, National tentatively embraced moral conservatism, one aspect of which was a greater willingness to intervene in the home lives of beneficiaries through authoritarian social policy. These interventions tended to be focused on female-headed sole parent families. In the context of these changes, I use a governmentality approach to examine how the social dilemma was repeatedly posed, but not solved, by successive neoliberal governments. The thesis is in two parts. The first part sets out historical context, events and policies, and the second part applies critical discourse analysis to three case studies, each of which illustrates different moments in the development of neoliberal social policy in New Zealand.

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  • Changing food habits of New Zealanders of European descent 1870-1970 : an anthropological examination of the mechanisms of cultural change

    Mitchell, Janet (1995)

    Masters thesis
    University of Otago

    Between 1870 and 1970 both the culture and food habits of New Zealand European society underwent change. In the past food habits have been examined using either an historical approach or consumption and nutritional data. These approaches however have not explained how change has occurred. Anthropologists working in other countries have approached this problem in several different ways. A structural approach to meals and the meal system gives answers to why food habits are slow to change. But this approach does not address change. A sociological approach which takes account of changes in the society explains how the interplay of societal factors can cause change but it does not account for the stability of food habits over long periods. This study combines these approaches to give an answer to the phenomenon of stability and change which characterised European New Zealanders' food habits from 1870-1970. Evidence of change in food habits and in the culture was linked to changing social conditions, ideas about food and changes in technology. Material on the topic was collected from written sources - in particular recipe books were found to be a valuable tool. In this study the evidence established that while all of the factors mentioned above played a role in the transformation of food habits in European New Zealand society, substantive change at any one time was linked to the social conditions that influenced women's role in the household

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  • The ecology and ethnobotany of karaka (Corynocarpus Laevigatus)

    Stowe, Christopher James (2003)

    Masters thesis
    University of Otago

    Historically there has been considerable debate over the origin of karaka ( Corynocarpus laevigatus J.R. et G. Forst.) in New Zealand. In contrast, the extent and importance of prehistoric arboriculture in New Zealand has received little attention in the literature. This study reviews the ecology and ethnobotany of karaka and investigates its cultural and natural biogeography. Maori migration traditions frequently state that karaka was introduced to New Zealand. However, molecular evidence and finds of fossil seeds of late Oligocene age show that karaka is endemic to New Zealand. Therefore, Maori traditions probably relate to the translocation and cultivation of karaka within the New Zealand region, for which there is abundant anecdotal evidence. Karaka fruits were a valuable addition to the Maori diet and were likely to have functioned as a replacement for traditional Polynesian tree crops. The preparation of karaka seeds also had Polynesian precedents and entailed a rigorous regime of steaming and soaking to rid the kernel of its toxic elements. There is data to suggest selection for fruit size and/or nutritional value in cultivated karaka populations. A database of karaka distribution was compiled and populations classified as 'cultural' or 'unknown' on the basis of spatial association with archaeological sites. Groves classed as cultural were assumed to be cultivated or translocated by pre-historic Maori. Lack of effective seed dispersal by birds and the longevity of the trees, mean that the contemporary distribution of karaka provides a reasonable template for the extent of its prehistoric translocation and cultivation within New Zealand. Karaka has a distinct cultural and natural biogeography. The greatest overlap between cultural and unknown trees occurred in the northern North Island while the majority of trees in the lower North Island, and all trees in the South Island were classed as cultural. Prior to the arrival of Polynesians in New Zealand, karaka was probably restricted in distribution to the Northland/Auckland region. Its natural range was then extended by human translocation and cultivation to the lower North Island, South Island, Kermadec Islands, Chatham Islands and many other in-shore islands off New Zealand. Climate variables were fitted to the distribution data and discriminant analysis used to further test the classification of karaka into cultural and unknown populations. Significant differences were found in climatic parameters between groups. Cultural karaka were found in environments with greater solar radiation seasonality, higher evaporative demands and greater soil moisture deficits than unknown karaka. The climate profile of karaka was closer to that of other tree species currently restricted to the northern North Island than with more widely distributed species. Furthermore, the climate profile and location of cultural karaka is biased towards the same environmental correlates of pa and pit site locations, further indicating that karaka was a cultivated tree crop. The extensive translocation of karaka by Maori means that it has the potential, with the application of molecular methods, to serve as a marker for prehistoric settlement and mobility. Preliminary work was begun on this aspect and a predictive model is presented of the possible relationships within and between populations of karaka.

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  • Power of my Maori name: Stories of indigenous struggles in white New Zealand

    Stevens , Alexander Windsor (2012)

    Masters thesis
    University of Otago

    Every day in Aotearoa (New Zealand), people of Maori ethnicity (the aboriginal peoples of Aotearoa) will experience their indigenous names being mispronounced when accessing health and social services. The New Zealand Government and the Ministries that come under including The Ministry of Health and The Ministry of Social Development continue to work towards reducing barriers for Maori who access their services. Despite this work there appears to be a gap in addressing this specific issue around pronouncing Maori peoples names correctly. This report investigates the gap identified by working with 20 Maori participants that have Maori names over a six month period in 2011. This research report used a mixed method approach of narratives and statistics, overarched by a Kaupapa Maori methodological approach. The aim of this report is to capture the lived experience of the effect of mispronunciation of a Maori name when accessing health and social services. The desired outcome of the research is to inform medical and social service practice, by encouraging Professionals (my emphasis) to find solutions to support better outcomes for their Maori clients from their first ka nohi ki te ka nohi (face-to-face) interaction. In this report the writer refers to the Maori as the indigenous people of New Zealand in contrast to Tauiwi (other). It is acknowledged that there is no single way of being Maori as Maori people’s values, beliefs and practices are diverse and different within whanau, iwi to iwi, hapu to hapu. However from the literature there are common threads and values that the Maori population generally engages in. This is what is drawn upon and woven from the literature and into this report while recognising the many ways that Maori people express their identity and experiences.

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