14,468 results for Doctoral

  • Livelihood Strategies and Environmental Management Practices in Northern Thailand National Park Communities : A dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Natural Resource Management at Massey University, Palmerston North, New Zealand

    Phongchiewboon, Aurathai (2016)

    Doctoral thesis
    Massey University

    In Northern Thailand, the establishment of national parks is at the forefront of efforts to achieve biodiversity conservation and environmental management while providing socio-economic benefits to society. However, national parks regulations and development interventions have created both opportunities and constraints for the Indigenous hill tribe communities living within the national parks. These communities have, out of necessity, adapted and developed their livelihood strategies and environmental management practices to maintain their socio-economic welfare and ecological sustainability. This study employed Participatory Rural Appraisal (PRA) as a mixed qualitative research strategy to investigate the livelihood strategies and environmental management practices in Doi Suthep-Pui, Doi Inthanon, and Ob Luang National Parks in Northern Thailand. The main research methods used were interviews, observation, and document analysis to support data that gained from the PRA methods. The aim of this study is to gain insight into the livelihood strategies and environmental management practices of six Indigenous hill tribe communities living in the parks. Interviews were conducted with villagers, national park officials, academics, and representatives from non-government organisations and tourism agencies. The interview data was also analysed to investigate how co-management initiatives and livelihood development projects by national parks officials and external organisations influence Indigenous communities’ livelihood strategies. It was found that the livelihood strategies of the Indigenous hill tribe communities encompass a diverse combination of activities related to their social and ecological relationships in order to ensure sustained socio-economic well-being. Communities engage in sustainable agricultural practices, community-based natural resource management activities and community-based ecotourism enterprises as their significant livelihood strategies. However, while there has been some consultation, co-management, and collaborative policy-making between government and local communities, further improvement of transparency, consistency and accountability is needed. It is argued that greater community empowerment and participation in natural resource management decisions is crucial to enhance both sustainable livelihoods and environmental conservation efforts within Northern Thailand’s national parks.

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  • Dynamics of pyroclastic density currents : : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Earth Sciences at Massey University, Palmerston North, New Zealand

    Breard, Eric Christophe Pascal (2016)

    Doctoral thesis
    Massey University

    Pyroclastic density currents (PDCs) are the most dangerous mass flows on Earth. Yet they remain poorly understood because internal measurements and observations are hitherto non-existent. In this thesis, the first measurements and views into experimental large-scale PDCs synthesized by “column collapse” provide insights into the internal structure, transport and emplacement dynamics of dense PDCs or pyroclastic flows. While from an outside point of view, PDCs resemble dilute gravity currents, the internal flow structure shows longitudinal and vertical complexities that greatly influence the PDCs‟ propagation and emplacement dynamics. Internal velocity and concentration profiles from direct observations provide the evidence of an unforeseen intermediate zone that plays an important role into the transfer of mass from the ash-cloud to the underflow. The intermediate zone is a “dense suspension” where particle cluster in bands to form mesoscale structures. These reduce particle drag and yield an extreme sedimentation rate of particles onto the newly-formed underflow. These findings call into question the existing paradigm of a continuous vertical concentration profile to explain the formation of massive layers and an underflow from ash-clouds. Instead, a sharp concentration jump occurs between the intermediate zone, with concentrations of the order of few volume percent, and the underflow, with concentrations of c.45%. PDCs were found to be composed of 4 main zones identified as the underflow, and the ash-cloud head, body and wake. Following the evolution of the PDC structure over time allows the formation of a complex ignimbrite deposit sequence to be uncovered, reproducing experimentally the “standard ignimbrite sequence” reported from field studies. Experiments revealed that each flow zone deposited the particulate load under contrasting emplacement timescales (spanning up to 5 orders of magnitude), which are primarily controlled by the concentration of the zone. The ash-cloud head is the most dynamic zone of the PDC, where proximally mass is intensively transferred downward and feeds the underflow front, while at all times, the finest particles are entrained upward and feed the wake through detachment of large Kelvin-Helmholtz instabilities. Subsequently, kinematic coupling between the moving underflow and overriding ash-cloud leads to a forced-supercriticality, preferentially affecting the head. The wide range of particle sizes and densities yield a spectrum of gas-transport behaviours ranging from a poorly coupled and rapid-sedimenting mesoscale regime up to a homogeneously coupled long-lived suspending regime. Internal velocity and concentration profiles illuminate the role of boundary velocity, which yields forced-acceleration of the ash-cloud. Kinematic coupling of the ash-cloud with the underflow induces a velocity at the lower flow boundary, while shear stress at the ash-cloud/underflow wanes and results in the shrinking of the maximum velocity and concentration heights. Therefore, the ash-cloud can reach high velocities and multiply its destruction potential. The experimental work presented in this thesis provides the first datasets of the internal physical properties of PDCs, which can be used to test the validity of current numerical models and highlight their limitations. This thesis also presents the study of a small hydrothermal blast that occurred at Mt. Tongariro, New Zealand, on the 6th of August 2012. The study of the blast is subdivided into two phases: the PDC phase and the ballistic phase. The detailed study of the PDC along the main propagation axis highlighted the role of the longitudinal zoning of the current, which was reflected in the complex tripartite deposit architecture. The study of the blast-derived ballistic crater field revealed a zone of high crater density that was related to the focus of ballistic trajectories around the main explosion direction. Simple inverse ballistic modelling provided evidence for a shallow blast (c. 5° above horizontal) from Te Maari. Furthermore, a comparison of ballistic block lithologies confirmed the origin of the elongated succession of craters or fissures formed by successive blasting during the eruption.

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  • Modelling food breakdown and bolus formation during mastication : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Bioprocess Engineering at Massey University, Palmerston North, New Zealand

    Gray-Stuart, Eli Mark (2016)

    Doctoral thesis
    Massey University

    Mastication is a complex process that transforms food into a bolus which can be swallowed safely. However, it can be simplified within an engineering context, where the mouth is the equipment carrying out a unit operation to convert ingested food (raw material) into a safe-to-swallow bolus as the process output. Two questions emerge from this observation (i), ‘What processes transform the food from its initial state into a bolus?’ and (ii), ‘How do humans assess when the food is ready to initiate swallowing?’ This research examines these questions and a mathematical model is developed which can track the bolus properties during mastication. A range of common foods with contrasting textures were examined in an observational study to investigate the rate processes of mastication. A wide range of breakdown pathways and textures were observed, from the brittle fracture of carrots to the work softening of a fibrous beef steak. However, despite differences in their structure and properties, breakdown is dominated by a small number of rate processes. Size reduction and work softening occur at occlusion and account for majority of the structural breakdown. Absorption, dissolution and melting are generally more subtle. These are facilitated by mixing, which is the circulation, gathering, folding and placement of food on the occlusal plane. Mechanical sensory testing (MST) occurs simultaneously to breakdown as the food is manipulated around the mouth during occlusion and between chews. During occlusion this provides gross information about the toughness and hardness, whereas between chews the tongue-palate interactions provide more detailed information about yield and flow. These MST’s assess the properties of volume, adhesion, bolus deformation, particle deformation and particle size. Adhesion refers to the binding forces between the food particles and the oral surfaces. Bolus deformation is important for boluses that do not contain individual particles. If they do then swallowability is constrained by their size and individual deformability. In order for safe swallowing, thresholds for each of the MST properties must be met. These were justified using a hazard and operability study of swallowing, on the premise that attempting to swallow a bolus which does not meet the threshold property could result in aspiration or choking. As mastication proceeds, the properties assessed by the MST’s are evaluated against the required threshold properties and contribute to the decision making process of whether to swallow or continue chewing. From this analysis, this work proposes a universal conceptual model of mastication that combines the rate processes, the MSTs and a decision making model. The conceptual model was then described mathematically. It is universal, that is, it is not specific to any food type, because solid foods follow similar physical breakdown paths where occlusion is of primary importance followed by the incorporation of saliva and the other rate processes. Model parameters require in-vivo experiments about the breakdown dynamics of specific foods. Subject variability was avoided by using single subject studies for three separate foods; brown rice, a sweetened gelatine gel and peanuts embedded in a food matrix. Each case study explored a limited number of rate processes and food properties. Bolus properties predicted by the model were compared to the experimental data. The output of the model, including particle size distribution and moisture content, closely matched the data during mastication and at swallow point using input parameters fitted from the single subject experiments. This work provides a platform for further research into mastication modelling. It is recommended the mathematical model be expanded to mechanistically describe the mixing and work softening of non-particulate food boluses. Additional experimental work would achieve a better understanding of the heat transfer in the mouth which would improve the models ability to handle heat sensitive foods. The model developed here has the potential to aid future food design where a particular breakdown pathway is desired and will reduce the number of time intensive in-vivo experiments needed.

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  • Photo-identification and its application to gregarious delphinids: Common dolphins (Delphinus sp.) in the Hauraki Gulf, New Zealand : A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Marine Ecology at Massey University, Albany, New Zealand

    Hupman, Krista E (2016)

    Doctoral thesis
    Massey University

    Common dolphins (Delphinus sp.) remain one of the most poorly understood delphinids within New Zealand waters. Baseline data on their abundance, site fidelity, movement patterns, and social structure remain unknown. This thesis applies photo-identification (photo-id) methods to fill in this data gap and provide the first comprehensive assessment of abundance, site fidelity, movement patterns, and social structure of Delphinus within New Zealand waters. Traditional cetacean photo-id relies on identification of dorsal fin nicks and notches. Photo-id is, therefore, rarely applied to common dolphins due to the lack of distinctive markings for individual identification and their gregarious nature. This study, however, applied this technique to identify unique individuals by examining dorsal fin nicks and notches in combination with dorsal fin pigmentation patterns in an effort to provide an additional stable feature for individual identification. Of all individuals examined, 95.3% exhibited dorsal fin pigmentation, with 92.7% manually identified using pigmentation as the only identifying feature. Novel computer vision and machine learning techniques were applied to examine pigmentation patterns. The correct individual was identified via pigmentation patterns alone 52.5%, 70.8%, and 78.7% of the time within the top-1, top-5, and top-10 matches, respectively. Furthermore, 79.9% of individuals were able to be classified as adult or immature based on pigmentation patterns alone. Overall, results suggested that pigmentation patterns are stable over time (for up to 11 years), although it is not known what proportion of the population exhibits such stability. Pigmentation patterns proved to be a reliable means of identification and can be used as a primary feature for identifying individual common dolphins in the Hauraki Gulf (HG). Future studies should trial this technique for this species in other worldwide populations. To estimate population parameters, mark-recapture (MRC) analysis can be conducted. This thesis examined the challenge of using this technique to estimate population parameters for common dolphins in the HG. The main challenges identified included the: high portion of unmarked animals; low levels of distinctiveness, and; the gregarious transient nature of Delphinus. Despite such challenges, reliable photo-id protocols were developed to increase the accuracy of individual identification and produce estimates of population parameters. These protocols included: combining the use of nicks and notches with pigmentation patterns as a primary feature for identification; classifying individuals as highly distinctive (D1), distinctive (D2), or non-distinctive (D3); the development of a distinctiveness threshold to catalogue individuals, and; for population analysis, stratifying data by the level of individual distinctiveness (by examining differences between D1 individuals only compared to D1&D2 individuals combined). The use of these protocols enabled the identification of 2,083 unique individual common dolphins in the HG between 2010 and 2013. Sighting records from these 2,083 individuals were used in a POPAN framework to estimate population parameters. The total population abundance was then calculated using a mark ratio (for D1 only and D1&D2 individuals) to account for the proportion of unmarked dolphins in the population. The best model selected for D1 individuals included constant survival and probability of entry and time dependant capture probability (ø(.) p(t) β(.)), whereas for D1 and D2 individuals combined, probability of entry varied by time (ø(.) p(t) β(t)). Apparent survival was constant for both D1 (0.767) and D1 and D2 (0.796) individuals. The low apparent survival estimates are likely caused by emigration of transient dolphins. Capture probability varied over time for both D1 (range=0.021-0.283) and D1 and D2 (range=0.006-0.199) individuals. Probability of entry remained constant for D1 individuals (0.062) but varied over time for D1 and D2 individuals (range=0.000-0.413). The total population was estimated at 7,795 dolphins (CI=7,230-8,404) when only D1 individuals were included, but increased to 10,578 individuals (CI=9,720-11,512), with the addition of D2 individuals. The photo-id protocols used here allowed maximised use of the photo-id data and provided a useful approach to estimate population parameters of poorly marked gregarious delphinids. The techniques applied here could be used for MRC studies of other Delphinus populations, or for other similar low marked gregarious species. Considering the large number of individuals found to use the HG, the level of site fidelity for common dolphins within this region was assessed. Likewise, an assessment was conducted to determine if individuals move between regions, primarily to the Bay of Plenty (BOP), and additionally to the Bay of Islands (BOI) and the Marlborough Sounds (MS). Common dolphins displayed long-term site fidelity to the HG, with 2,399 marked individuals identified within this region between 2002 and 2013. These individuals were classified as occasional visitors (95.1%), moderate users (4.8%), and frequent users (0.1%). Individuals were also found to move between neighbouring regions including the Bay of Plenty (2.2%) and Bay of Islands (0.2%). In addition, a number of individuals were defined as travellers moving between multiple regions. Travellers exhibited opposite seasonal peaks in re-sightings between the HG and the BOP, which may represent an influx of individuals from these neighbouring regions. A total of six travellers were observed to move between the HG and the BOP in stable pairs. Knowledge of common dolphin site fidelity to the HG and movement patterns to other regions is vital for identifying management units and, therefore, providing effective conservation of this species in New Zealand waters. The definition of management units requires knowledge of a species social structure. Findings presented here provided the first analysis of Delphinus social structure in the Hauraki Gulf. Considering common dolphin associations may be difficult to study due to their gregarious nature, an assessment of which sighting thresholds were best for conducting social structure analysis was conducted. Sighting thresholds were assessed to determine which is best for: maintaining reliability without the loss of data; association indices, and; representation of the true social structure. Precision of the data increased when the sighting threshold decreased. Levels of association were reported to decrease when restricting the number of times an individual was observed. Notwithstanding, maximum association indices were similar regardless of the sighting threshold used. Social structure analysis was considered to be a ‘somewhat representative’ pattern of the true social organisation of common dolphins in the HG. For these reasons, a threshold of four or more sightings was considered the best representation of social structure for this population Common dolphins in the HG displayed fluid associations at the population level (Coefficient of Association; COA=0.02), although some individuals were found to associate with particular companions (maximum COA=0.46). The population was also classified as a well-differentiated society (S=1.230). Individuals did not form short-term companionships but instead preferred long-term associations. Structured relationships existed, some of which lasted for periods of up to 70 days. The examination of the sociality of gregarious species is therefore possible using photo-id techniques and provides information on association patterns for common dolphins within New Zealand waters. Such information is important to collect over the long-term to be able to determine relationships between individuals which can be used to develop effective management this population. To efficiently manage common dolphins in the HG and New Zealand waters, it is important to be able to identify the natural and anthropogenic pressures faced by populations. To examine this, photo-id was also applied to assess the prevalence of lesions and deformities. The majority (78.0%) of individuals photo-identified exhibited lesions, whereas only 0.5% had deformities. Of all body segments examined, the anterior peduncle exhibited the highest percentage of lesions or deformities (91.1%). A significant difference in the prevalence of lesions between the leading and trailing edges of dorsal fins was also evident. A number of possible causes of lesions and deformities were highlighted including intra- or inter-specific interactions, congenital malformations, environmental conditions, infectious origins, fisheries and vessel interactions, and/or human-induced environmental stressors. Considering the number of pressures faced by this population it is important to monitor lesion and deformity prevalence over time to highlight natural or human induced impacts within the environment. As common dolphins remain part of an open super-population, which inhabits the north-eastern coastline of New Zealand’s North Island, they are therefore, subject to cumulative pressures. Considering a baseline abundance estimate is available, further monitoring and meaningful re-evaluations of this population is required. Proactive as opposed to reactive conservation is, therefore, recommended to ensure effective management of this species in New Zealand waters.

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  • Journey together through the three years: An evaluation of the personal tutor system, a student support model embedded in a Bachelor of Nursing programme in New Zealand : A thesis presented in partial fulfilment for the requirements for the degree of Doctorate in Education at Massey University, Palmerston North, New Zealand

    Hoare, Kathryn Maree (2015)

    Doctoral thesis
    Massey University

    Student support is an important part of tertiary education with different models, systems and approaches used internationally and nationally. The personal tutor system is one such approach to student support embedded within a new Bachelor of Nursing curriculum in a New Zealand tertiary institution. Through the personal tutor system students were assigned a lecturer, an academic member of staff, at the commencement of their study, for the duration of their programme. The purpose of the personal tutor system was to offer students support with their academic development and personal guidance that involved: scheduled and ad hoc meetings; monitoring of progress; personal assistance; and directing some students to seek additional support. Using a mixed methods design, the personal tutor system was evaluated at the time the first student cohort completed the new programme. The study focused on factors that influenced the personal tutor system experience. Third year students and lecturers were invited to participate in two‐phase data collection that involved the completion of a questionnaire (third year students: n=86 and lecturers: n=19) followed by semi‐structured interviews (third year students: n=38 and lecturers: n=10). Most participants confirmed that their personal tutor system experience was positive. Interpersonal interaction between students and lecturers was a key factor, as relationships were central to the personal tutor system. Flexibility was important as the personal tutor system was not a one‐size‐fits‐all approach to student support. At times, competing responsibilities gave rise to undue tension particularly with lecturers’ availability and accessibility for support. Unfamiliarity with the personal tutor system guidelines led to different interpretations for use and consequently confusion with support expectations. However, almost all participants acknowledged the value and potential for the personal tutor system in the BN programme. Recommendations for changes to the personal tutor system included: the creation a proportional co‐ordination role for ongoing management; a review of the guidelines that linked to support resources; time integrated into the BN programme for flexible arrangements with meetings and contact; and a time allocation for lecturers’ workload with resourcing for associated responsibilities.

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  • Analysis of spectral response patterns of Kiwifruit orchards using satellite imagery to predict orchard characteristics of commercial value before harvest : : a thesis presented in fulfilment of the requirements for the degree of PhD Prod Tech in the School of Engineering and Advanced Technology at Massey University, Palmerston North, New Zealand

    Mills, Linda Yvonne (2015)

    Doctoral thesis
    Massey University

    Several characteristics of kiwifruit determine its value to the kiwifruit marketing company, Zespri Ltd, and to the grower. The foremost of these is the dry matter content. Much effort is expended in predicting the final dry matter content of the fruit as early in the season as possible so that the optimal dry matter content can be achieved. Dry matter content is currently measured through a destructive 90-fruit protocol that may be repeated several times in a season on each maturity block. Remote sensing data available from modern satellites can provide four-colour (red, green, blue and near-infrared) data with resolution down to 1-2m, less than the size of one kiwifruit vine. Many indices can be created from these and correlated to the characteristics of plants with indifferent results. This thesis presents the development of an index wherein the four colours are used to create a three-dimensional unit colour vector that is largely independent of light level. This transform was used to allow the direct visualisation of data from a number of satellite images of the Te Puke kiwifruit growing area in New Zealand over five years, for which dry matter content values were available from the 90-fruit protocol. An attenuation model was chosen to correct the top-of-atmosphere light intensities recorded by the satellite cameras to those at ground level. The method of Hall et al., (1991) was found to reduce the variation of fiduciary pixels by the largest amount and was used. The visualisation revealed that there was an axis along which dry matter was ordered by magnitude. A regression line of best fit was applied to this data producing an R2 value of 0.51 with a standard mean-square error of 0.76. This is significantly lower than the average mean-square error of 1.05 for the 90-fruit protocol. Comparison of the predictive power of other indices, based on one image, showed a range of R2 values of 0.008 to 0.49. The method developed in this thesis produced an R2 of 0.70 for the same data.

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  • From Government to Governance: Small and Medium Enterprise Policy Development in New Zealand 1978 to 2008 : A thesis presented in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Management at Massey University Wellington, New Zealand

    Jurado, Tanya Ruth (2016)

    Doctoral thesis
    Massey University

    Widespread recognition of the importance of SMEs and their contribution to the economy means that successive New Zealand governments, between 1978 and 2008, placed increasing emphasis on SME policy. SME policy developed over time from being an incidental outcome of general economic policy to targeting particular SME sectors and engaging stakeholders and SMEs themselves in this process. Few studies have examined how this policy process evolved, and this research addresses the deficit by providing a critical overview of New Zealand SME policy development between 1978 and 2008. It examines how SME policy in New Zealand developed over the thirty-year period, identifying the main influences (or inputs) in SME policy development, and what policy outputs were set in place. The approach draws on business history methods and utilises primary sources, such as archival documentation, media reports, contemporary SME research and interviews with participants who played key roles in the development of SME policy. Historical analysis facilitates the examination of the range and diversity of SME policies used over the period under review. The research provides an overview of the external domestic and international influences that shaped and informed SME policymaking processes, and the challenges of meeting the often contradictory nature of government objectives in the socio-economic domain. It shows how over time the social cohesion policy objective, although still underplayed, became more pronounced. Principal inputs into SME policy are found to be the economic and stakeholder contexts, both set in an overall institutional environment. Whereas in the early period the economic context was the primary input into SME policy, by 2008 the input of stakeholders (researchers, academics, industry associations, chambers of commerce, among others) was more significant. The research concludes that, as attitudes and economic thinking changed, so too did SME policy and the way policy developed. A shift to the entrepreneurship paradigm contributed to a fundamental recalibration of approaches – from direct SME support such as the Small Business Agency, to predominantly indirect contextual support. SMEs were no longer considered ‘little big businesses’ but complex and heterogeneous enterprises and the role of stakeholders became more noticeable. Understanding how SME policy has altered over three decades assists researchers, policymakers and other SME stakeholders by contextualizing the evolution of thinking and approaches. As an outcome of this study, stakeholders will have additional clarity to help them contribute to the ongoing development of New Zealand SME policy.

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  • Exploring informal caregivers' health needs from a capability perspective : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Manawatū, New Zealand

    Horrell, Barbara Mary (2015)

    Doctoral thesis
    Massey University

    Despite more than forty years of informal caregiving research, the health needs of informal caregivers continue to generate considerable scrutiny. Most commonly, caregiving is portrayed as burdensome and a health risk, although positive and ambivalent experiences have been reported. This study uses the Capability Approach (CA; e.g. Nussbaum, 2000; Sen, 1980) as a theoretical framework to add another perspective to the existing literature regarding informal care provision for older people. Participatory principles informed the research, insofar as the participants were accorded flexibility, control, and helped to co-analyse some of the data. Undertaken in New Zealand, the research comprised two studies. In Study One, 60 caregivers anonymously participated in an online research forum, in an evolving joint discussion of their health needs. Template analysis (King, 2012) of the forum postings, based on Nussbaum’s (2007) capabilities list, highlighted the relational nature of caregiving and the importance of emotions to the caregiving role. Emotional attachment influenced the caregivers’ freedom to choose how they lived their lives, and emotions in general were implicated in the complexities and tensions associated with the caregiving process. An important finding was the self-abnegation of the caregivers who neglected self-care in order to provide care for another. These results led to a second, prospective study that explored in more depth the role of emotions in the everyday lives of caregivers. Six informal caregivers participated in Study Two which involved up to six successive interviews with each participant. Four of the participants kept a solicited diary, which informed the subsequent interviews. Narratives from the second study provided more nuanced data that affirmed the first study’s findings, and contributed to the overall finding that an ethic of care underpins the provision of informal care for older people. The participants valued having the capability to care, evidenced by their emotional attachment, attentiveness and commitment to providing competent care. The participants approach to self-care and their own wellbeing was inseparable from the wellbeing of the person being cared-for. These findings have important implications for social policy aimed at improving the experience of providing informal care for older people.

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  • Statistical methods for estimating tephra source and dispersal : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Statistics at Massey University, Palmerston North, New Zealand

    Kawabata, Emily (2016)

    Doctoral thesis
    Massey University

    Tephra refers to any pyroclastic fragments ejected from a volcanic vent and its dispersal is one of the major hazards with explosive eruptions. The attenuation of tephra fall thickness is most commonly estimated after contouring field measurements into smooth isopachs. I explicitly describe the variability in thickness by using a semiempirical tephra attenuation relation as a link function. This opens the way to fitting models to actual tephra observations through maximum likelihood estimation (MLE). The method is illustrated using data published from the 1973 Heimaey eruption in Iceland. Complex eruptions commonly produce several phases of tephra fall from multiple vents. When attempting to precisely reconstruct past eruptions from the geological record alone, separate phases are often indistinguishable. Augmented by a mixture framework, the MLE attenuation model was able to identify the sources and directions of tephra deposition for the 1977 Ukinrek Maars eruption in Alaska, US, from only the tephra thickness data. It was then applied to the unobserved 1256 AD Al-Madinah eruption in Saudi Arabia. The estimation of the spatio-temporal hazard from a monogenetic volcanic field is criti- cally dependent on a reconstruction of past events. The Auckland Volcanic Field (AVF) has produced about 50 volcanoes in the last 250,000 years. Although inconsistent, age data for many of these volcanoes exist from various dating methods with various re- liabilities. The age order of some pairs is also known due to the overlaying of lavas (stratigraphy). A discussion is provided on how informative priors are obtained via ex- pert elicitation, on both the individual volcano ages, and the reliabilities of the dating methods. A possible Bayesian model for reconciling the available inconsistent volcano age data to estimate the true eruption ages is also discussed. To improve these eruption age estimates, some of the volcanoes can be correlated with the better dated tephra layers recovered from five maars in the field. The likelihood of any combination of volcano and tephra, incorporating the spatial variability based on the attenuation model and temporal components, is evaluated and is maximised numer- ically using linear programming. This statistical matching provides an improvement in the volcano age-order model and age estimates of the volcanoes in the AVF.

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  • "Where did I park my car?" : a mixed methods investigation on mild cognitive impairment diagnosis in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of a Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand. EMBARGOED until 11 May 2017

    McKinlay, Alison R (2015)

    Doctoral thesis
    Massey University

    Mild cognitive impairment (MCI) is defined as an objective impairment in cognitive function which spares everyday functional ability. The syndrome is shrouded in controversy regarding definition, cut-off criteria, and clinical utility. Consequently, it is an uncertain label for the client being diagnosed by their healthcare practitioner. To date, minimal research in New Zealand has focused on MCI within specialist assessment services. Reasons for this paucity of literature will be discussed throughout this thesis. The current research aimed to identify how practitioners deliver and perceive cognitive impairment diagnosis, and examine how clients respond to receiving this diagnosis. Client experiences were framed within the common sense model (CSM). This theory originates from health psychology, where coping behaviour is said to be influenced by the cognitive representations that a person has about their condition. Although the framework is previously discussed in relation to chronic illness, international researchers have started to examine the utility of the model in explaining MCI diagnosis response. Given this context, the CSM framework guided the client-focused components of this thesis. In Study One, 57 practitioners who diagnose cognitive impairment completed a questionnaire on labels applied to MCI and beliefs about the value of diagnosis delivery. Responses were analysed using content analysis to gain an impression of professional practice. Cognitive disorder - not otherwise specified (CD-NOS), early dementia, and normal ageing were reported to additionally label the symptoms of MCI in clinical practice. In Study Two, client responses were examined in a small clinical sample (N = 9) diagnosed with MCI and CD-NOS. Participants were interviewed twice within six months of initial diagnosis. Interpretative phenomenological analysis was used to gain insight into how people cope and make sense of their diagnosis over time. Descriptive analyses were also undertaken with a subset of Study Two data to examine changes and differences in coping strategies over time. Findings suggest that participants may not see their diagnosis as an illness or significant health threat in the first six months following diagnosis. This prompts a question on the suitability of an illness model with reference to diagnosis response. Findings from this research add to the literature by highlighting practice associated with an evolving form of clinical diagnosis in NZ.

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  • The association between equine Papillomavirus type 2 and equine Squamous cell carcinomas : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Palmerston North, New Zealand

    Knight, Cameron Greig (2015)

    Doctoral thesis
    Massey University

    Appendix A removed due to copyright restriction.

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  • Identification of biomarkers of colitis to monitor effects of dietary omega-3 polyunsaturated fatty acids in the interleukin-10 gene-deficient mouse model of inflammatory bowel diseases : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science at Massey University, Manawatū, New Zealand

    Berger, Nadja (2016)

    Doctoral thesis
    Massey University

    Inflammatory bowel diseases (IBD) are characterised by chronic inflammation of the gastrointestinal tract including the colon (colitis). Increased dietary intake of salmon, which is rich in eicosapentaenoic acid (EPA), was well tolerated by IBD patients, leading to a perceived decrease in symptoms. However, better knowledge of the mechanisms by which EPA-rich diets affect IBD severity, and appropriate biomarkers for assessing these effects, are needed for potential targeted nutritional interventions. This dissertation aimed to determine the temporal effects (early (9 weeks of age) vs. established (12 weeks)) of a diet containing 3.7% EPA, and the dose-dependent effects (15% to 45%) of a salmon diet at 12 weeks of age, on the severity of colitis. Molecular responses in colon and/or liver of the interleukin-10 gene-deficient (Il10-/-) mouse model of IBD and healthy mice were assessed. Caecum digesta, urine and blood were mined to identify biomarkers (microbiota, metabolites and genes) of these responses. The EPA diet reduced the severity of colitis only in 12-week-old Il10-/- mice. This response was associated with changes in gene expression associated with lymphocyte function, eicosanoid signalling and peroxisome proliferator-activated receptor gamma signalling. The blood immune cell gene expression profile did not correlate with reduced colitis in these mice, but the urine metabolite profile was related to changes in colonic tryptophan metabolism. The effects of the salmon diets on colitis were dose-dependent in 12-week-old Il10-/- mice. The intermediate amount of salmon (30%) reduced the severity of colitis and lymphocyte-related gene expression, while enhancing genes in metabolic pathways. Tryptophan metabolism was not affected in these mice, but the urinary metabolite profile correlated with effects on hepatic tocopherol metabolism, as shown by reduced abundance of gamma-carboxyethylhydroxychroman glucoside. The abundances of V. akkermansia, Eubacterium spp., and an unclassified Rikenellaceae were further affected in these mice. This is the first report describing molecular responses in the colon and liver of Il10-/- mice fed a salmon diet associated with reduced colitis. Ultimately these responses could be validated for use in humans, and potentially enable management of IBD with diet.

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  • Shear work induced changes in the rheology of model Mozzarella cheeses : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Manawatu, New Zealand

    Sharma, Prateek (2016)

    Doctoral thesis
    Massey University

    Mozzarella cheese is a pasta filata type of cheese. Its manufacture includes a kneading – stretching step that creates a fibrous protein network and distributes fat-serum channels to attain desirable melt functionality on a pizza. During processing and manufacturing of pasta-filata cheese, large deformations take place. For appropriate characterization of a food material, rheological evaluation should be conducted in similar operating conditions, length scales and time scales to those taking place in the actual process. Development of the typical fibrous pasta-filata structure of mozzarella cheese depends on composition and process variables. Critical process variables in the development of cheese structure are time, temperature and shear. In this study we studied the effect of shear work on rheology, structure and melt functionality of model Mozzarella cheese. Three types of model cheeses (full-fat, non-fat and full-fat with added tri-sodium citrate) were prepared by working cheese components together at 70 oC in a twin screw Blentech cooker. Varied amounts of shear work input (2.8-185 kJ/kg) were given to the cheese samples using 50, 150 and 250 rpm screw speeds. Samples were subjected to a range of rheological tests, confocal laser scanning microscopy, fat particle size measurements (DLS) and melt functionality evaluation. While measuring steady shear viscosity of Mozzarella-type cheeses in a rotational rheometer at 70oC, three main difficulties were encountered; wall slip, structural failure during measurement and viscoelastic time dependent effects. A flow curve method was successfully devised to measure steady shear rheology by using serrated plates as surface modification to avoid wall slip, giving enough measurement duration at low shear rate to avoid viscoelastic effects and selecting limited shear steps to cause minimum structural changes. These techniques enabled successful measurement of steady shear viscosity of molten Mozzarella-type cheeses at 70oC at shear rates up to 250 s-1. Strong work thickening was observed for full fat Mozzarella cheese from steady shear rheology, oscillatory rheology, creep, elongational viscosity and tensile testing data. Steady shear rheology and melt functionality were found to be strongly dependent on total shear work input. An exponential increase in consistency coefficient (K from power law model) was observed with increasing amounts of accumulated shear work, indicating work thickening behaviour. An exponential work thickening equation is proposed to describe this behaviour. Excessively worked cheese samples exhibited liquid exudation, poor melting and poor stretch. Nonfat cheese exhibited similar but smaller changes after excessive shear work input. At lower shear work inputs (70 kJ/kg) it behaved like a viscoelastic solid with low frequency dependence. A definite critical point for structural and viscoelastic transition was identified at a medium shear work level (~ 58 kJ/kg at 150 rpm). Similar viscoelastic property changes occurred in non-fat cheese suggesting that major changes were taking place in the protein matrix during working. Confocal microstructures plus macroscopic observations showed systematic changes in structure with increased shear work inputs with unmixed buttery liquid observed at 58 kJ/kg. At very high shear work inputs, > 75 kJ/kg, striations or anisotropy in the microstructures had disappeared and small micro-cracks were evident. Volume-weighted mean fat particle size decreased with shear work input and particle size distributions also changed. To account for the short and long term relaxation response behaviour, a 4-element Burger‘s model was found adequate for fitting the creep data of model cheese at 70 oC but a 6-element model was required at 20 oC. As shear work input increased, retarded compliance decreased and zero shear viscosity increased indicating the more elastic behavior of the cheeses with higher shear work input. Fracture stress and strain for longitudinal samples from elongated full fat cheese did not vary significantly with shear work input up to 26.3 kJ/kg then decreased dramatically at 58.2 kJ/kg. Longitudinal samples with shear work input G‘ > elongational viscosity > consistency coefficient, K. It was concluded that the dominant contributor to the changes in rheology, structure and melt properties with increased shear work was shear induced structural changes to the protein matrix. An increase in calcium induced protein-protein interactions after high shear work at 70 oC. In summary, this thesis provides useful insights to shear work induced changes in material properties. It proposes useful linkages between the manufacturing process and the application of model Mozzarella cheese using appropriate rheological methods. Since the linkages were validated for only one composition and in only one processing environment, it is proposed that they should be tested in other conditions. In order to build a more complete picture, a molecular level study is proposed for future work to elucidate chemical changes during working and find appropriate linkages with physical and functional characteristics.

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  • R² and stock price informativeness : new empirical evidence : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Finance at Massey University, Palmerston North, New Zealand

    Hao, Wei (2015)

    Doctoral thesis
    Massey University

    Abstract taken from Introduction (page 7)

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  • The Invention of Papahurihia : A thesis submitted in fulfilment of the requirements of the degree of Doctor of Philosophy in History at Massey University, Albany, New Zealand

    Ward, Judith (2016)

    Doctoral thesis
    Massey University

    Historians portray Papahurihia as the first Māori prophet and founder of a syncretistic religion that combined elements of Judaic and Christian theology with Māori beliefs. They also say he observed a Saturday Sabbath and that his followers were known as Jews. This thesis disputes those conclusions. It re-examines the commentaries of the CMS missionaries in the Bay of Islands from the context of 1830s Protestant evangelicalism and draws on the texts of the Wesleyan and Roman Catholic missionaries and European settlers to show how Papahurihia behaved in various situations. It argues that historians have failed to take account of the way that Protestant and Catholic writers saw Papahurihia through the lenses of their own religions. The thesis recreates Papahurihia in the context of the Ngāpuhi seasonal cycle and links him to the persistence of ceremonies like the hahunga. It argues that historians have overlooked the extent to which he operated on a Māori concept of time and how the missionaries and Europeans made assumptions about the behaviour of Papahurihia and his followers based on the Christian calendar. The thesis concludes that Papahurihia responded to the advent of Christianity in a way that was consistent with the behaviour of tohunga at the time, rather than as the founder of a syncretistic religion. It also concludes that the historiography on Papahurihia ultimately went awry because historians interpreted the missionaries’ comments about him from a secular perspective.

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  • A study of some New Zealand natural products.

    Jogia, Madhu Kant (1985)

    Doctoral thesis
    University of Otago

    xii, 348 leaves :col. ill. ; 30 cm. Includes bibliographical references. University of Otago department: Chemistry

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  • Taxonomies of Taiwanese Aboriginal Musical Instruments

    Cheng, Lancini Jen-hao (2015)

    Doctoral thesis
    University of Otago

    This research aims to discover the indigenous taxonomy systems of Taiwanese aboriginal instruments. This is a cross-cultural investigation providing a panoramic perspective on the musical instruments of Taiwanese aborigines (Austronesians). The term ‘musical instrument’ is used in its broadest sense to refer to all sound-producing instruments in this research. There are many reasons for undertaking this research. For example, until now, few people have known what forms of aboriginal musical instruments have existed throughout the island of Taiwan, and there has been little scholarly discussion about their indigenous names and classifications. The original contribution of the research is its ethnographic fieldwork component, which results in new information concerning indigenous instruments and taxonomic schemes from the opinion of 48 cultural insiders across 17 different aboriginal groups in Taiwan. The researcher’s approach is based on participant observation - by recording the musical activity in either traditional or contemporary contexts, and by interviewing cultural insiders about their traditional music. Also, the researcher analyses the instrumental form, function and meaning of aboriginal instruments across synchronic and diachronic development. The findings in this dissertation provide a new understanding of many unknown musical instruments from different aboriginal groups (e.g. Bunun, Kavalan, Pazih-Kahabu, Puyuma, Rukai, Sakizaya, Siraya and Tsou). This investigation also makes original contributions to extend the instrument type and the numerical entry of the Hornbostel-Sachs system of musical instrument classification. Moreover, this dissertation provides a link between Taiwanese aboriginal instruments and other Austronesian musical instruments. In summary, the many factors that influence indigenous taxonomies of Taiwanese aboriginal instruments include linguistic factors (onomatopoeia, overlapped radicals, and the verbalising affix), how they are played, the materials used in their construction, their performance contexts, as well as players’ gender, social status and religion.

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  • The free child health care scheme : implications for New Zealand general practice

    Dovey, Susan May (2002)

    Doctoral thesis
    University of Otago

    xv, 260 leaves :ill. ; 30 cm. Includes bibliographical references.

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  • Haematology and inflammation in infections of farmed red deer (Cervus elaphus)

    Cross, John Philip (1991)

    Doctoral thesis
    University of Otago

    xiii, 180, i, 39 leaves, [1] folded leaf :ill. (some col.) ; 30 cm. Includes bibliographical references. University of Otago department : Microbiology

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  • Habitats and macroinvertebrate fauna of the reef-top of Rarotonga, Cook Islands : implications for fisheries and conservation management

    Drumm, Darrin Jared (2005)

    Doctoral thesis
    University of Otago

    xiii, 173, [6] leaves :ill. ; 30 cm. Includes bibliographical references. University of Otago department: Marine Science. "December 2004."

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