7,313 results for 2010, Doctoral

  • Dancing to a different tune: adaptive evolution fine-tunes protein dynamics

    Donovan, Katherine Aleisha (2015)

    Doctoral thesis
    University of Canterbury Library

    The molecular mechanisms that underpin adaptive evolution are not well understood. This is largely because few studies relate evolved alleles (genotype) with their physiological changes (phenotype), which move a population to better fit its environment (adaptation). The work described in this thesis provides a case study exploring the molecular changes underlying adaptive evolution in a key allosteric enzyme. It builds upon a long-term evolution experiment by Richard Lenksi, where twelve replicate populations of Escherichia coli have adapted in parallel to better fit their low-glucose environment. I focused on the allosteric enzyme pyruvate kinase type 1, since this has been shown to adapt to this environment. First, I used X-ray crystallography to determine a higher resolution structure (2.2 Å) than previously available of the wild-type PK1 enzyme for comparison with the evolved enzymes. I resolved the ambiguous space-group problem that affects these crystals, and demonstrated that the kinetic function of the recombinant enzyme is the same as previously reported. In addition, I propose a new model for allosteric activation: a combination of structural and dynamic analyses determined that the allosteric signal is transferred by a series of dynamic changes between the allosteric site, upon fructose-1,6-bisphosphate binding, and the active site for increased substrate binding. The functional analyses demonstrated that all eight evolved PK1 enzymes have a reduced activity compared to the wild-type PK1 at physiological substrate concentrations. Not only did the evolved PK1 enzymes show a parallel decrease in activity, but they all showed changes to substrate binding affinity and seven of the eight showed an altered allosteric activation mechanism. These results suggest that natural selection has selected for enzymes with a reduced activity by altering the functional mechanism of the evolved enzymes. However, in crystal and in solution structure characterisation determined that all of the evolved PK1 enzymes have maintained the same structural fold as the wild-type PK1. Although the fold is the same, substrate binding promiscuity suggested a change in the flexibility of the enzyme, allowing substrates of different sizes and shapes to bind. Computational and experimental dynamics studies determined that natural selection has selected for reduced activity by altering the dynamics in all of the evolved PK1 enzymes, and it has used altered dynamics to change the allostery of the enzymes. Therefore, this study provides the first example of adaptive evolution fine-tuning protein dynamics to alter allostery. This thesis describes the molecular mechanisms underlying one aspect of adaptation of Escherichia coli to the low-glucose environment in Lenski’s long-term evolution experiment. The adaptive mutations in Escherichia coli’s pyruvate kinase type 1 serve to increase the availability of phosphoenolpyruvate for glucose uptake. From a molecular perspective, natural selection has selected for adaptive amino acid substitutions that produce an enzyme with reduced catalytic activity at low phosphoenolpyruvate concentrations, thus decreasing phosphoenolpyruvate consumption. In addition, the adaptive mutations have altered the enzymes’ affinity for the allosteric activator (fructose- 1,6-bisphosphate), fine-tuning them to match the concentration of fructose-1,6- bisphosphate in the cell at the point of glucose re-introduction. Overall, this work describes the intricate relationship between genetic changes and the resulting phenotype and demonstrates the parallel nature of adaptation for this particular case study. Whereby, parallel changes are mapped from organismal fitness, to enzyme function and to enzyme structure. The dynamic changes, however, are not parallel thus making the prediction of specific changes in adaptive evolution difficult.

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  • Modernizing Childbirth in Colonial Bengal: A History of Institutionalization and Professionalization of Midwifery, c.1860-1947

    Guha, Ambalika (2015)

    Doctoral thesis
    Victoria University of Wellington

    In colonial India, medicalization of childbirth has been historically perceived as an attempt to ‘sanitise’ the zenana (secluded quarters of a respectable household inhabited by women) as the chief site of birthing practices and to replace the dhais (traditional birth attendants ) with trained midwives and qualified female doctors. This thesis has taken a broader view of the subject but in doing so, focusses on Bengal as the geographical area of study. It has argued that medicalization of childbirth in Bengal was preceded by the reconstitution of midwifery as an academic subject and a medical discipline at the Calcutta Medical College. The consequence was the gradual ascendancy of professionalized obstetrics that prioritised research, surgical intervention and ‘surveillance’ over women’s bodies. The thesis also shows how the medicalization of childbirth was supported by the reformist and nationalist discourses of the middle-class Bengalis in the late nineteenth and early twentieth centuries. The thesis begins from the 1860s when the earliest scientific essays on childbirth and pregnancy began to appear in Bengali women’s magazines such as Bamabodhini Patrika. It ends in the 1940s, when nationalism profoundly influenced the professionalization of obstetrics - midwifery being perceived as the keystone in a nation’s progress. Bengal being the earliest seat of British power in India it was also the first to experience contact with the western civilization, culture and thought. It also had the most elaborate medical establishment along western medical lines since the foundation of the Calcutta Medical College in 1835. It is argued in the extant literature that unlike the West where professionalized obstetrics was characterised as essentially a male domain, the evolving professional domain of obstetrics in Bengal was dominated by female doctors alone. Questioning that argument, the thesis demonstrates that the domain of obstetrics in Bengal was since the 1880s shared by both female and male doctors, although the role of the latter was more pedagogic and ideological than being directly interventionist. Together they contributed to the evolution of a new medical discourse on childbirth in colonial Bengal. The thesis shows how the late nineteenth century initiatives to reform birthing practices were essentially a modernist response of the western educated colonized middle class to the colonial critique of Indian socio-cultural codes that also included an explicit reference to the ‘low’ status of Bengali women. Reforming midwifery constituted one of the ways of modernizing the middle class women as mothers. In the twentieth century, the argument for medicalization was further driven by nationalist recognition of family and health as important elements of the nation building process. It also drew sustenance from international movements, such as the global eugenic discourse on the centrality of ‘racial regeneration’ in national development, and the maternal and infant welfare movement in England and elsewhere in the inter-war years. The thesis provides a historical analysis of how institutionalization of midwifery was shaped by the debates on women’s question, nationalism and colonial public health policies, all intersecting with each other in Bengal in the inter-war years. The thesis has drawn upon a number of Bengali women’s magazines, popular health magazines, and professional medical journals in English and Bengali that represent both nationalist and official viewpoints on the medicalization of childbirth and maternal and infant health. It has also used annual reports of the medical institutions to chart the history of institutionalization of midwifery and draws upon archival sources - the medical and educational proceedings in particular - in the West Bengal State Archives and the National Archives of India.

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  • The impact of intellectual capital on firm performance among R&D engaging firms

    Ariff, Arifatul Husna Mohd (2016)

    Doctoral thesis
    Victoria University of Wellington

    This thesis investigates the impact of aggregate intellectual capital (IC), and its elements, human capital, structural capital and tangible capital, on firm performance. In addition, the study also examines the impact of past research and development (R&D) activity on the relationship between IC and firm performance. The study employs the original and modified Value Added Intellectual Coefficient (VAICTM) models to measure IC. Firm performance is measured from two different perspectives: market and financial. The study uses a sample of 1,328 firm-year observations drawn from multinational firms which engaged in R&D activity over the period 2006-2013 and were listed on the U.S. stock exchanges. Using ordinary least squares regression, the study confirms that aggregate IC has a significant positive impact on both the market and financial performance of firms. Human capital has no significant impact on market performance, but it has a significant positive impact on financial performance. Structural capital and tangible capital each have a significant positive influence on both the market and financial performance of firms. In addition, the study finds that past R&D activity has a significant positive impact on the relationship between aggregate IC and both market and financial performance. However, the study finds mixed results for the role of past R&D activity on the relationship between the IC elements and firm performance. The study contributes to the existing literature by providing empirical evidence on the impact of IC on firm performance among multinational R&D engaging firms. The study also adds to the literature by providing empirical evidence on the role of R&D activity in influencing the relationship between IC and firm performance and thus enhances the current understanding of the role of IC and R&D. In addition, the study contributes to the methodology by proposing a modification to the original VAIC model and empirically tests the resulting modified VAIC model. The study thus provides empirical evidence of the impact of IC on the market performance and financial performance of firms. This evidence should be useful to firms in developing their IC and R&D policies, to users of financial statements in evaluating the benefits from IC among R&D engaging firms, and also to accounting standard setters in identifying the information on IC that should be included in financial reports.

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  • Epidemiology and production effects of leptospirosis in New Zealand sheep : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy In Veterinary Sciences at Massey University, Manawatu, New Zealand

    Vallée, Emilie (2016)

    Doctoral thesis
    Massey University

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  • “You Bring It, We’ll Bring It Out” Becoming a Soldier in the New Zealand Army : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Social Anthropology at Massey University Manawatū, New Zealand.

    Harding, Nina (2016)

    Doctoral thesis
    Massey University

    The transition from civilian to soldier is a process of identity acquisition. Based on participant-observation, this thesis follows a cohort of new soldiers through the first year and a half of their careers in the New Zealand Army, from their first day of Basic Training to their first overseas deployment. Both the Army as an institution and its individual soldiers are explicitly self-reflexive, and I use not only academic theory but also soldiers’ own theories of identity and identity acquisition to make sense of the experience of becoming a soldier. I show that although recruits undergo change in becoming soldiers, they simultaneously retain pre-service identities. Using Pierre Bourdieu’s theory of practice, I argue that civilians join the Army because of a shared “primary habitus”, a pre-existing identification with action, productivity and continual self-improvement through facing challenges that forms recruits’ earliest embodied understandings of themselves. The relationship between this “practical” habitus and the new soldier habitus to be acquired is key to understanding the civilian-soldier transition. While civilians draw on and thus fulfil the primary practical habitus in becoming soldiers during initial training periods, once socialised they find the Army much less challenging, and therefore may find that their need to be involved in meaningful action is not met. Although the practical habitus is behind and can make sense of the cohort’s actions, it is a mode of identity that has not often been recognised as such by academics, due to the fact that they do not share it. However, I show that it is more important in generating soldiers’ practice than the modes of identity that are usually employed to understand them: gender, sexuality, ethnicity and nationality. Therefore, I argue that anthropologists should not limit analysis to traditional axes of identity.

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  • Exploring New Zealand’s Rural Education Activities Programmes (REAPs): Social capital in a lifelong learning and community development context : A thesis presented in partial fulfillment of the requirements for the degree of Doctorate of Education at Massey University, Palmerston North, New Zealand

    Morrison, Derek Ryan (2016)

    Doctoral thesis
    Massey University

    This research explored the extent to which social capital is an approach used by New Zealand’s Rural Education Activities Programmes (REAPs) to contribute to rural education. Social capital was defined for the purposes of this study as the resource residing in networks of individuals, based on mutual trust and shared social norms, which can be brokered and mobilised to achieve social benefits, particularly in the application of knowledge and skills. A conceptual framework lays out four key elements from this definition which were investigated: networks, trust, social norms, and brokerage. Given the lack of published material on REAPs and their work, a primarily qualitative design was utilised. Set within a constructivist epistemology and interpretive phenomenological methodology, in-depth interviews with REAP managers and questionnaires for REAP learners were used to collect data. The aim was to explore the lived experiences of these two REAP groups to identify their views on how REAPs operate so that those views could be considered within the social capital framework above. An inductive-deductive-inductive analysis approach was used to maximise the extent to which findings reflected participant language. Findings from both REAP managers and learners supported the strong presence of the four social capital elements in REAP activity. In many cases the qualitative themes were closely related, both within and across the four social capital elements. Both strong (social) and weak (institutional) forms of trust were described as influencing learner participation in networks, where REAPs played a role in brokering that participation within similar (bonded) and differing (bridged) networks. REAPs made use of trusted relationships and valued-based decision making to gain local community and cultural knowledge to ensure the relevance of responsive learning activities. The result was enhanced confidence and identity of learners to take part in other social activities, including further learning and collective action. Lived examples of these elements supported a social capital approach that fit well with the lifelong learning and community development processes outlined by the REAP mandate. These processes were defined holistically to consider the integration of individuals’ beliefs, viewpoints, and behaviours as much as skills and knowledge. The explored social capital approach within lifelong learning and community development contexts, yields clear recommendations for Government, REAPs, and partner organisations. Flexibility, values/identity-based education, and closing network gaps to facilitate innovation come through as REAP social capital practices that could inform policy and partnerships across the whole of the education sector. Further research is needed to more closely consider the complex relationships of the identified social capital themes. In terms of emergent themes, a deeper exploration of innovation produced through brokerage within REAP activity is highlighted as a key area of research for future.

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  • Organising Therapists’ Emotional-Social Skills: Are Therapists that Different? : A thesis in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology at Massey University, Palmerston North New Zealand

    Marwick, Andreas (2016)

    Doctoral thesis
    Massey University

    Wampold and Imel (2015) argue that therapeutic outcomes may be more dependent on variables associated with therapists than treatment systems. An element of these therapist variables include the emotional and social skills of therapists, however, to date, little has been done to investigate the relationships between these therapy factors. One exception to this is pilot research conducted by my supervisors, their students, and myself (Harvey, Marwick, Baken, Bimler, & Dickson, 2016). This thesis aims to replicate and extend on this pilot research as to better understand therapists’ emotional and social skills in practice. Using three complementary approaches including thematic analysis of therapist transcripts, a date-specific literature review, and revision of foundational research, Harvey et al.’s original pool of emotional and social skills was revised and extended. Subsequently, using a statistical method for mapping psychological constructs, therapists’ emotional practices were transformed into a ‘map’ with three spatial dimensions, which was generally supported by comparative reliability checks including a validation study with a foreign-language sample. Finally, the nature of emotional practice was further investigated by administering a questionnaire of emotional practice items to 79 therapists. From this, eight salient practice constructs were identified. Statistical links were also found between these and both demographic data and a modified measure of the therapeutic relationship. Furthermore, using Q-analysis, a general consensus of responding was found between therapists’ emotional response patterns and as a result, a tentative pathway to therapists’ practice styles was developed. From these findings important research and clinical applications are apparent.

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  • Wellness Protocol: An Integrated Framework for Ambient Assisted Living : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy In Electronics, Information and Communication Systems At School of Engineering and Advanced Technology, Massey University, Manawatu Campus, New Zealand

    Ghayvat, Hemant (2016)

    Doctoral thesis
    Massey University

    Smart and intelligent homes of today and tomorrow are committed to enhancing the security, safety and comfort of the occupants. In the present scenario, most of the smart homes Protocols are limited to controlled activities environments for Ambient Assisted Living (AAL) of the elderly and the convalescents. The aim of this research is to develop a Wellness Protocol that forecasts the wellness of any individual living in the AAL environment. This is based on wireless sensors and networks that are applied to data mining and machine learning to monitor the activities of daily living. The heterogeneous sensor and actuator nodes, based on WSNs are deployed into the home environment. These nodes generate the real-time data related to the object usage and other movements inside the home, to forecast the wellness of an individual. The new Protocol has been designed and developed to be suitable especially for the smart home system. The Protocol is reliable, efficient, flexible, and economical for wireless sensor networks based AAL. According to consumer demand, the Wellness Protocol based smart home systems can be easily installed with existing households without any significant changes and with a user-friendly interface. Additionally, the Wellness Protocol has extended to designing a smart building environment for an apartment. In the endeavour of smart home design and implementation, the Wellness Protocol deals with large data handling and interference mitigation. A Wellness based smart home monitoring system is the application of automation with integral systems of accommodation facilities to boost and progress the everyday life of an occupant.

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  • The effect of maternal nutrition during mid- to late- pregnancy on ewe and lamb behaviour and the association with lamb survival : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Palmerston North, New Zealand

    Grönqvist, Gabriella Veronica (2015)

    Doctoral thesis
    Massey University

    Lambing percentage in New Zealand has increased by almost 30% in the last 20 years. This increase is associated with a greater percentage of twin- and triplet-born lambs which have lower survival rates than singletons. The behaviour of the ewe and her lambs has been associated with lamb survival, however, relevant data on the effect of ewe mid-pregnancy body condition score (BCS) and nutrition on ewe and lamb behaviour under New Zealand pastoral farming conditions is scarce. This research included seven experiments investigating the effects of feeding ewes, with a BCS of 2.0 to 3.0 at mid-pregnancy, either ad libitum or only sufficient to meet pregnancy maintenance requirements from mid- to very late-pregnancy, on ewe and lamb behaviour at 3 to 24 hours after birth. The association between behaviour and lamb survival was also investigated. Observations on ewe and lamb behavioural were conducted at tagging (3 to 18 hours after birth) and in a triangle pen test at approximately 12 or 24 hours after birth. The effects of ewe mid-pregnancy BCS and feeding on behaviour were somewhat inconsistent across experiments, possibly due to variations in the timing and length of feeding treatments. Feeding ewes ad libitum in comparison to pregnancy maintenance requirements did not consistently improve the maternal behaviour score (MBS) of the ewe. This is not surprising as neither of the feeding treatment groups were nutritionally restricting. There was some evidence to suggest that lambs born to ewes offered the pregnancy maintenance diet exhibited a greater need, possibly due to a weaker ewe-lamb bond than lambs born to ewes on the ad lib treatment. This need was characterised in twins, in chapter four, by greater low-pitched bleating rates and decreased time to contact, suck and follow the dam. Similar, but inconsistent results were reported in other chapters. Further, when investigating the relationship between behaviour and survival, it was found that twin-born lambs with the greater need (followed their dam more quickly) were more likely to die. The opposite relationship was found in triplet-born lambs, which may be a reflection of greater competition for milk within triplet-litters compared to twin-litters. Thus, in both twin- and triplet-born lambs following behaviour is an indicator of mortality. The practical use of this behaviour as a tool to predict lamb survival is limited.

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  • Facial Expressions and Context Effects : A Thesis Presented in Partial Fulfillment of the Requirements for the Degree of of Doctor of Philosophy in Psychology at Massey University, Albany, New Zealand

    Xu, Hui (2016)

    Doctoral thesis
    Massey University

    It is common and important for us to recognise facial expressions in our daily life. Research on recognition of facial expressions was often carried out using isolated faces, which leads us to ignore accompanied contextual information (e.g. vocal sound, body language). Chapter 4 used bodily and vocal expressions as contextual stimuli to investigate whether there are context effects on recognition of all six basic facial expressions. The results generally showed that recognition of facial expressions benefits from congruent contextual stimuli, while recognition of facial expressions is impaired by incongruent contextual stimuli. Chapter 5 examined whether the observed context effects vary with the level of intensity of facial expressions. The results showed that context effects are influenced by the level of intensity of facial expressions and revealed the opposite trend of the magnitude of facilitation effects and interference effects as level of intensity of facial expressions was increased. The following chapter 6 investigated another important aspect of context effects, that is, whether attentional resources influence the observed context effects. The results showed that the magnitude of context effects was reduced when the perceptual load of task-relevant tasks was increased, at least for context effects from bodily expressions to the recognition of disgusted facial expressions. All the data collected showed commonalities and differences in the pattern of context effects on recognition of facial expressions. Future studies might concentrate on the differences among these facial expressions to explore whether there exists a consistent pattern of context effects for all six facial expressions or to refine the existing models regarding recognition of facial expressions to better predict context effects for facial expression recognition.

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  • Bayesian Modelling of Direct and Indirect Effects of Marine Reserves on Fishes : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Statistics at Massey University, Albany, New Zealand.

    Smith, Adam Nicholas Howard (2016)

    Doctoral thesis
    Massey University

    This thesis reviews and develops modern advanced statistical methodology for sampling and modelling count data from marine ecological studies, with specific applications to quantifying potential direct and indirect effects of marine reserves on fishes in north eastern New Zealand. Counts of snapper (Pagrus auratus: Sparidae) from baited underwater video surveys from an unbalanced, multi-year, hierarchical sampling programme were analysed using a Bayesian Generalised Linear Mixed Model (GLMM) approach, which allowed the integer counts to be explicitly modelled while incorporating multiple fixed and random effects. Overdispersion was modelled using a zero-inflated negative-binomial error distribution. A parsimonious method for zero inflation was developed, where the mean of the count distribution is explicitly linked to the probability of an excess zero. Comparisons of variance components identified marine reserve status as the greatest source of variation in counts of snapper above the legal size limit. Relative densities inside reserves were, on average, 13-times greater than outside reserves. Small benthic reef fishes inside and outside the same three reserves were surveyed to evaluate evidence for potential indirect effects of marine reserves via restored populations of fishery-targeted predators such as snapper. Sites for sampling were obtained randomly from populations of interest using spatial data and geo-referencing tools in R—a rarely used approach that is recommended here more generally to improve field-based ecological surveys. Resultant multispecies count data were analysed with multivariate GLMMs implemented in the R package MCMCglmm, based on a multivariate Poisson lognormal error distribution. Posterior distributions for hypothesised effects of interest were calculated directly for each species. While reserves did not appear to affect densities of small fishes, reserve-habitat interactions indicated that some endemic species of triplefin (Tripterygiidae) had different associations with small-scale habitat gradients inside vs outside reserves. These patterns were consistent with a behavioural risk effect, where small fishes may be more strongly attracted to refuge habitats to avoid predators inside vs outside reserves. The approaches developed and implemented in this thesis respond to some of the major current statistical and logistic challenges inherent in the analysis of counts of organisms. This work provides useful exemplar pathways for rigorous study design, modelling and inference in ecological systems.

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  • Frontiers of decision theory : This dissertation is submitted for the degree of Doctor of Philosophy in Economics, School of Economics and Finance (Albany) Massey University

    Pan, Siwen (Addison) (2016)

    Doctoral thesis
    Massey University

    The well-known jury paradox – the more demanding the hurdle for conviction is, the more likely it is that a jury will convict an innocent defendant – heavily relies on Bayesian updating. However, with ambiguous information (e.g., a forensic test with accuracy of 60%, or more), standard Bayesian updating becomes invalid, challenging the existence of this paradox. By developing novel theoretical models and by testing their predictions in laboratory settings, this thesis advances our understanding of how individuals process more realistically imprecise measures of information reliability and how this impacts on information aggregation for the group decision-making. Hence, our findings inform the institutional design of collective deliberation, from small to large group decision-making.

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  • A study of Innovative Entrepreneurship in Marlborough, New Zealand : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy (Arts) in Social Anthropology at Massey University, Albany, New Zealand

    Lynn, Amanda (2015)

    Doctoral thesis
    Massey University

    This study responds to the call, made by Anthropologist Alex Stewart, for anthropologists to re-engage with the entrepreneur. The broad aim of this study is to describe and analyse the lived experiences of innovative entrepreneurs in Marlborough, New Zealand. The study is informed by a constructivist-interpretivist paradigm. The research design is based on contemporary interpretative phenomenological analysis conducted within long term participant-observation fieldwork. The study is transdisciplinary in that it is informed by the disciplines of anthropology, economics, psychology and business. Innovative entrepreneurs are an important focus of study due to their role in economic and social change. Thus far anthropological studies have not focused on the innovative entrepreneur in New Zealand. This study makes an original and significant contribution to entrepreneurship studies. I present rich, empirical data on innovative entrepreneurs viewed through the anthropological lens. As such, my study embraces the “humanness” of the participating innovative entrepreneurs. I describe five shared themes that coalesce in a process that guides innovative entrepreneurship. These shared themes are: perfectionistic striving (an adaptive and targeted striving for improvement), pragmatism (openness to new ideas, testing and applying them), development (purposive change within and outside of the self), meaningful reward (validation of value) and being valuable (solving problems to improve outcomes). This process begins with the desire, formed early in life, to be valuable and leads to a life-long process of problem identification and solution construction. This results in self-development as well as developmental outcomes such as businesses and products. I recommend a life span human development approach to future research that includes the collection of deep empirical data and offer a new definition of the innovative entrepreneur. While the innovative entrepreneurs in my study desire to be valuable, the social world in which they are embedded is not always compatible with them. Through analysis of the rich points in the social data I present original social models describing social sets in Marlborough and obstructive processes that usurp institutional power by reinforcing these sets. As entrepreneurs become more visible and influential as leaders they can be drawn into obstructive processes causing some innovative entrepreneurs to avoid—as much as possible—both the local support institutions and the social sets. This has implications which I discuss and I recommend further research to expand upon my findings.

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  • A culturally-focused life cycle sustainability assessment: Analysis of forestry value chain options with Māori land owners : A thesis presented in partial fulfilment of the requirements of Doctor of Philosophy in Life Cycle Management At Massey University, Palmerston North, New Zealand

    Pizzirani, Stefania Maria (2016)

    Doctoral thesis
    Massey University

    The purpose of this research was to 1) explore the potential for the more distinctive representation of Māori culture in Life Cycle Sustainability Assessment (LCSA), and 2) understand the relationship between culturally-focused LCSA and the Māori decisionmaking process. These two interrelated aspects were investigated through participatory engagement with three members of the Ngāti Porou iwi (tribe), and through collaborative development of three forestry LCSA scenarios (radiata pine, rimu, and mānuka). Aligning with principles of kaupapa Māori research, a participatory LCSA methodology approach was created which encapsulated five phases: 1) understand Ngāti Porou aspirations and concerns, 2) co-develop options for forestry scenarios, 3) co-develop and select LCSA indicators (including a cultural indicator), 4) LCSA indicator data collection and modelling, and 5) communication of results. The methodology utilised a mixed methods approach as Stage 1, 2, 3, and 5 are predominantly qualitative while Stage 4 is predominantly quantitative. Culture was represented in the participatory LCSA in two ways. Firstly, a bespoke cultural indicator (Cultural Indicator Matrix) was co-developed to distinctly include culture within LCSA. The Cultural Indicator Matrix was based on and adapted an existing cultural decision-making framework (i.e. the Mauri Model) in order to ensure its capability to represent both Ngāti Porou aspirations and the forestry value chains explored in this research. The Cultural Indicator Matrix was completed by each participant and subjectively measured the impact they perceived each forestry process or product had upon a range of Ngāti Porou aspirations. Secondly, a participatory research approach was utilised that itself made the LCSA process more culturally-focused. The participatory approach relied on active engagement with the research participants throughout the LCSA study, primarily with the utilisation of semi-structured interviews. Such collaborative participatory engagement with the research participants allowed for their cultural input, preferences, and knowledge at each stage of the LCSA process. This research has yielded several original and meaningful results: 1. The Cultural Indicator Matrix is a new culturally-focused mechanism which can be used to support the Māori decision-making process. The participants viewed the Cultural Indicator Matrix as an effective method for gathering community impressions of how potential forestry life cycle processes could impact upon their cultural aspirations. 2. The participants felt the participatory LCSA aspect was crucially important; the open and consistent communication between themselves and the LCSA practitioner provided them with more control, access to information, understanding of the LCSA process, and enhanced their acceptance of the final results. They considered that the results of the culturally-focused LCSA gave them “validation” and “direction”, and justified their interests in pursuing forestry options for their land. 3. The participatory LCSA process led to the identification of a need to formally include a Cultural Compliance process with the LCSA. The Cultural Compliance process is comprised of six cultural components occurring throughout the forestry life cycle. Recognition of these components helps to ensure that appropriate and necessary cultural considerations are taken into account during relevant forestry life cycle processes. It is unlikely that this insight would have been reached if not for the participatory engagement focus of this LCSA research. 4. The development and analysis of three forestry scenarios using a range of sustainability indicators generated distinctive datasets on the life cycles of radiata pine, rimu, and mānuka. As the rimu and mānuka scenarios are particularly underrepresented in forestry-life cycle literature, this research has provided a contribution to knowledge regarding these two forestry options. For the first time, indigenous culture has been represented alongside economic, social, and environmental impacts in LCSA. This comprehensive presentation of results facilitates the decision-making process by providing the decision maker(s) with information about the “big picture”, thus supporting educated and informed decisions. Furthermore, a culturally-focused LCSA approach helps to ensure that culture is not lost during the decision-making process, but rather is an active component. Finally, of critical importance, both the culturally-focused LCSA process and associated results will further enable the recognition cultural groups, including their values and aspirations. The explicit acknowledgement of culture in LCSA will engender more awareness and protection for culture, lessen the isolation and marginalisation of culture, and empower cultural groups to develop and pursue brave choices.

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  • An ecological perspective on the motivational trajectories of high school students learning English in rural areas in Vietnam : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Applied Linguistics at Massey University, Palmerston North, New Zealand.

    Pham, Huy Cuong (2016)

    Doctoral thesis
    Massey University

    This study explores the motivational trajectories of four students learning English at a rural high school in Southern Vietnam. It draws on a person-in-context relational view of motivation (Ushioda, 2009) as the overarching theoretical framework and uses ecological systems theory (Bronfenbrenner, 1993) as an analytical tool to develop insights into the ways motivation is implicated in a multiplicity of settings and social relationships. Specifically, it aims to identify motivational affordances for these students, the synergistic effects across settings on their language learning motivation, and their motivational trajectories within and across settings and relationships. The study utilises a qualitative case study design, relying primarily on interviews from social practice perspectives and observations. The data collection, spanning approximately one and a half years, comprised two main phases, one on-site and one off-site. In the first phase, data were gathered in different settings, including the school, the participants’ homes as a site for private tuition, and other more informal public spaces such as food stores. In the second phase, Skype interviews and Facebook exchanges were the main means of data collection. The findings suggest that while language affordances were evident in both formal and informal learning settings, students developed diverse individual motivational trajectories. Their motivational constructions resulted from a synergy of environmental and idiosyncratic elements pertinent to their own language learning conditions, social relationships, and personal appraisals of such affordances and learning opportunities. These relationships and students’ agentive use of resources were shaped and reshaped by their interactions with significant others within and across settings. Sociocultural features related to the school systems, local and national education policies, family traditions, cultural values, and future prospects also have synergistic impacts on their L2 motivation. The present study illustrates the value of interpreting the situated and dynamic nature of L2 motivation using an ecological paradigm. It also points to the need to adopt a set of data collection methods, tools, and data sources that diverge from more conventional means to explore L2 motivation. The study offers a fresh theoretical and methodological approach for future research geared towards lifewide adaptive perspectives on English language teaching and learning.

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  • Building community resilience in mine impacted communities : a study on delivery of health services in Papua New Guinea : a thesis presented in fulfilment of the requirements for the degree of Doctor Of Philosophy in Development Studies at Massey University, Palmerston North, New Zealand

    Kuir-Ayius, Dora Dau (2016)

    Doctoral thesis
    Massey University

    The purpose of this study was to explore the building of Community Resilience in mine-impacted communities in Papua New Guinea (PNG). The study aimed to establish the general relationship between community resilience, community capitals and the delivery of health services. It investigated the delivery of health services in three mining communities in PNG to see how these services contribute to or detract from the building of resilience. The study investigated relevant models of community resilience from the literature, and how the way policy functions in PNG can be related to these models. The study also developed a way of quantifying the impact of mining on health service delivery (through the use of community capitals) and the building of resilience in these communities. Furthermore, the thesis develops an indigenous, Melanesian-centric ‘Bilum Framework’ approach to resilience to create greater understanding of how resilience in the mining communities can be strengthened through improved access to health services. Three mining communities were selected as case studies, each representing a different stage of mining: (i) the beginning; (ii) the operational; and, (iii) post-mine closure. A mixed method approach comprising both quantitative and qualitative methods was used to collect data for this study. A survey questionnaire was designed to collect views of community members who accessed health services in their respective communities. Results from the survey questionnaire were converted to proxy indicators and led to the development of a Community Resilience Index (CRI) to provide a measure of resilience in each community. The qualitative research methods included document analysis, semi-structured interviews, and purposive observations. Document analysis was important in reviewing relevant policy documents and other literature to link theories to the experiences of the people while the latter methods contributed to describing people’s encounters in accessing health services. Analysis showed inconsistencies in the levels of resilience in these communities that varied with the stages of mining: both the beginning and post- mine closure stages demonstrated significantly lower levels of community resilience than the operational phase. Findings from the research indicated a lack of access to health services – a key influence in building resilience – is the result a range of factors including insufficient finances, weak sector governance, and the need for infrastructure and transport. The Bilum Framework is proposed as an approach that allows decision-makers to target assistance to strengthen and support specific community capitals and hence more effectively build community resilience in the mining communities in PNG.

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  • Judging Competency A study of in-training evaluation of veterinary students : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Education at Massey University, Manawatū, New Zealand

    Norman, Elizabeth J (2016)

    Doctoral thesis
    Massey University

    In-training evaluations are a common but highly criticised method of assessing the competency of veterinary students completing training. They involve assessment of on-going performance in the workplace, performed by the supervisor. They are highly feasible and one of the few ways that a student’s performance in an authentic context can be evaluated. Psychometric research has suggested, however, that in-training evaluations are unreliable, do not discriminate aspects of performance, and do not predict performance on other assessments, casting doubt on the credibility of scores. Research on rater judgement processes suggests, in contrast, that multiple aspects are discriminated and that accounting for context and inferred reasons for behaviour contributes to rater variability. Very little research has considered in-training evaluation in a veterinary context. In a mixed method study this research investigated how well the in-training evaluation used during clinical placements in one veterinary school captured the aspects of student performance it was designed to capture. It explored the supervisor’s view of student performance, and how that related to the dimensions being assessed in in-training evaluation, and to the constructs of competency articulated in frameworks. Complementary research strands involved analysis of semi-structured interviews with supervisors, common factor analysis of in-training evaluation scores, ordinal logistic regression relating factors to overall judgement, and thematic comparisons of findings with competency frameworks. Together, the nature of what supervisors considered, the dimensional structure of scores, and the relationship of dimensions with the overall judgement suggested that the in-training evaluation is both holistic and discriminating, and that important aspects of performance are student engagement and trustworthiness. The aspects captured by the evaluation aligned well with the design of the instrument, and generally well with the veterinary competency frameworks. However, some areas were highlighted where concepts of veterinary competency and the competencies required in different subdisciplines need further consideration by the profession. The findings give insights into the process of judgement of competency by veterinary supervisors that will inform further research. They support some aspects of a validity argument in relation to scoring processes, and inform the design of evaluation instruments by underscoring the construct-relevance of interrelated dimensions.

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  • Testing the relationship between gut permeability, elevation of systemic lipopolysaccharides and chronic disease : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Manawatu, New Zealand

    Gnauck, Anne (2016)

    Doctoral thesis
    Massey University

    The aim of my thesis was to test whether an increase in the permeability of the gut is accompanied by an increase in the level of systemic lipopolysaccharides (LPS), also referred to as endotoxin. These two parameters were firstly concurrently determined in healthy women after the treatment with a single dose of aspirin which is thought to temporarily increase the paracellular permeability of the intestine. Gut permeability and the levels of systemic LPS in healthy women were then compared with those in women with Crohn’s disease (CD) as the latter are thought to have chronically elevated paracellular permeability of the gut. Both groups also ingested a high fat drink which is reported to results in the elevation of systemic LPS. In addition, faecal calprotectin, a biomarker of ongoing inflammation in the gut, and LPS-binding protein (LBP), a proposed indirect biomarker for the exposure to LPS in the systemic circulation, were determined both in healthy women and in those with CD. Data indicated that both temporary and chronic increase in the paracellular permeability of the small intestine can be reliably determined by the 3-h excretion of lactulose. Further the combination of levels of faecal calprotectin and 3-h excretion of lactulose and mannitol is the most sensitive tool to distinguish between healthy subjects and those with CD. Hence, it is evident that the combination of those three parameters can be used to assess gut health. In contrast, the current available methods for the direct assessment of the systemic level of LPS/endotoxin i.e. the Limulus Amebocyte Lysate (LAL) assay for the quantification of endotoxin or ELISAs for the quantification of LPS, are not reliable as the former is interfered by constituents of serum and the latter failed to detect LPS from sources other than those provided from the manufacturer of the kit. Hence, studies suggesting that the consumption of high fat meals lead to elevations of systemic endotoxin and those suggesting that levels of systemic endotoxin is associated with the onset of metabolic syndrome are questionable. It is therefore advisable to repeat those studies when accurate methods for the quantification of LPS/endotoxin in the systemic circulation are available.

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  • Acceleration and Gifted Girls : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Education at Massey University, Manawatū, New Zealand

    Crawford, Margaret Evelyn (2016)

    Doctoral thesis
    Massey University

    This study on Acceleration and Gifted Girls investigates acceleration as an intervention in secondary education within girls’ schools in New Zealand. It explains the extent that acceleration is being used for whom and with what processes in the context of New Zealand single-sex education. It focuses particularly on acceleration. A national survey of single-sex girls’ schools provided a general view of acceleration practices and provisions. Three case studies offered a more in-depth exploration. Findings from this study emphasised that schools are designing and evaluating their provisions for their gifted and talented girls, with an emphasis on personalised learning and an appropriate curriculum. Acceleration is used, typically, as part of a continuum of provisions to challenge students at higher levels than their year level. Timetable flexibility, whole class and individual acceleration, multi-level pathways through NCEA, dual enrolment or full entry at universities are all included in the provisions offered to gifted girls. This study highlighted an association between a school’s culture of learning and the school’s culture of care of gifted and talented students. High levels of satisfaction relating to the ways in which schools provided for gifted and talented girls were expressed by both students and their parents.

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  • Development of novel nanoemulsions as delivery systems : A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, New Zealand

    Teo, Anges Hwee Ming (2016)

    Doctoral thesis
    Massey University

    In the past decades, emulsions have been widely used as delivery systems for incorporating bioactive compounds into foods. With the advancing of nanotechnology, smaller particles in the nanometric range (i.e. nanoemulsions) can be created with better properties that are more advantageous than conventional emulsions in terms of their stability to gravitational separation, optical clarity and better absorption of nutrients in drug delivery (with increased bioavailability). In particular, emulsification and solvent evaporation method has been used to produce nanoemulsions with optimum results. However, like conventional emulsions, protein-stabilised nanoemulsions become unstable when exposed to certain environmental stresses such as high temperatures, salt addition and extreme pH changes. Additionally, liquid emulsions are difficult to transport and use in some food systems while being susceptible to microbial spoilage. To remedy, a dry, stable emulsion system has to be obtained for their prospective future in food applications. The objective of this research was to develop nanoemulsions with useful attributes. The thesis consists of three main parts in which the first part studied the formation and properties of nanoemulsions using emulsification and solvent evaporation method; the second part delved into the making of dried nanoemulsion powders and the third part focused on the structural modifications of nanoemulsions and encapsulation of a bioactive compound lutein. To begin, an experimental study to optimise the conditions for producing nanoemulsions using emulsification and solvent evaporation methodology was performed under different processing conditions (microfluidisation pressures and number of passes), organic phase ratios and materials (oil types and emulsifiers). It was found that smaller oil droplets (around 80 nm in diameter) were achieved when increasing the microfluidisation pressure up to 12000 psi (80 MPa) for 4 passes at an organic phase ratio of 10:90. There was a progressive decrease in particle size with increasing emulsifier concentration up to a 1% (w/w) level for whey protein isolate (WPI) and lactoferrin but it did not decrease further at higher concentration. On the other hand, much larger oil droplets were formed in Tween 20 emulsions (120 – 450 nm). The environmental study showed that lactoferrin and Tween 20 emulsions have a better stability to pH changes (pH 2 – 12) and salt addition (0 – 500 mM NaCl or 0 – 90 mM CaCl2) than WPI stabilised nanoemulsions. After successful preparation of nanoemulsions, liquid nanoemulsions were converted to dried powders by spray drying or freeze drying. The nanoemulsions were mixed with different wall materials consisting of maltodextrin alone, trehalose alone or a 1:1 ratio of maltodextrin and trehalose at 10, 20 or 30% (w/w) solid concentration. Results showed that the powders containing 20% trehalose have better powder properties with lower moisture content and water activity, higher bulk density and good reconstitution in water. The freeze-dried powders showed excellent wettability and dispersibility in water but lower encapsulation efficiency than spray dried powders. In another part of study, nanoemulsions with modified interfacial structure were used to improve their stability to environmental stresses. The interactions between WPI and lactoferrin in aqueous solutions were first studied to explore the feasibility of using these two proteins to form complex interfacial structures at the droplet surface in the emulsions. Based on ζ-potential and turbidity measurements, both proteins were shown to interact with each other via electrostatic interactions at pH values between 6 and 8. The adsorption of protein layers on a gold surface that mimics the hydrophobic oil surface was also confirmed by a quartz crystal microbalance with dissipation (QCM-D) study. Next, a series of bi-layer nanoemulsions at different pH values and lactoferrin concentrations were prepared so as to determine the best conditions on the overall emulsion stability. It was shown that the stability of emulsions was dependent on both pH and lactoferrin concentration. At pH values close to pI of WPI (around pH 5), the nanoemulsions remained unstable regardless of the lactoferrin concentration used (0.25 – 5% w/w). The nanoemulsions at pH 6 were also unstable at low concentrations (0.5 – 1% w/w) presumably due to “bridging flocculation” and exhibited phase separation. Consequently, a lactoferrin concentration of 3% (w/w) was used to produce bi-layer nanoemulsions at pH 6. At pH 7 – 10, the bi-layer nanoemulsions were stable at all lactoferrin concentrations and formed a bi-layer structure at the interface of droplet. The formulated nanoemulsions (single layer and bi-layer emulsions) were subjected to a variety of environmental stresses and in vitro digestion under simulated gastrointestinal conditions. The emulsion stability to pH changes and salt addition was improved in the bi-layer emulsions containing WPI and lactoferrin when compared to the single layer nanoemulsions stabilised by WPI alone. However, the bi-layer emulsions were more susceptible to destabilisation on heating at temperatures above 60oC. The in vitro digestion of bi-layer nanoemulsions was similar to single layer nanoemulsions in which the protein hydrolysis of the interfacial layers results in extensive droplet flocculation. In subsequent formulations, lutein was incorporated in the emulsions as a model of bioactive compound for the application of nanoemulsions as a novel delivery system. The nanoemulsions well encapsulated lutein in their matrices with an encapsulation efficiency of 80% and contained small oil droplets (70 – 80 nm). All the emulsions were physically stable under the tested conditions up to 28 days at different storage temperatures (5, 20 and 40oC). However, there was a significant decrease in lutein content during storage especially at higher temperatures due to oxidative degradation. Nevertheless, the bi-layer nanoemulsions showed a better stability to lutein degradation. Based on in vitro cell toxicity studies on Caco-2 cells using MTT assay, both nanoemulsions did not show toxicity as the cell viability was more than 80% at 10 times or more dilution after 24 hours of incubation. The cellular uptake of lutein was higher in bi-layer nanoemulsions when compared to single layer emulsions. The present work demonstrated that nanoemulsions can be formed using emulsification and a solvent evaporation method. Dried microcapsules of nanoemulsions were formed with similar properties as their original nanoemulsions after reconstitution in water. The nanoemulsions with bi-layer interfacial structure have better stability to environmental changes than single layer emulsions. Nanoemulsions did not show more toxicity than their corresponding conventional emulsions with large oil droplets produced without the use of organic solvent. These have important implications in the use of nanoemulsions for encapsulation lutein or other bioactive compounds for applications in foods and beverages.

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