14,388 results for Doctoral

  • Probability-of-growth modelling to optimize the use of hurdle technology to achieve microbiological stability of high moisture processed cheese : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand

    Khanipour, Elham (2014)

    Doctoral thesis
    Massey University

    This thesis reports a study of the application of hurdle technology to high moisture, low acid ambient shelf-stable hot packed processed cheese analogue (PCA). Hurdle technology makes use of a combination of mild stress factors. A combination of these stress factors can be more effective in inhibiting or inactivating the growth of micro-organism than individual stress factors. The current study focused on the application of hurdle technology to inhibit the growth of the food pathogen, Clostridium botulinum (C. botulinum). This micro-organism poses a hazard for consumers and is capable of growth in low acid food (pH> 4.5). As there are difficulties in working with C. botulinum in laboratory trails, Clostridium sporogenes (C. sporogenes) was used as an analogue of C. botulinum. C. sporogenes is very similar to C. botulinum in growth characteristics but is not dangerous. The effectiveness of selected preservatives on the growth of the target micro-organism was expressed as the probability of growth and was modelled as function of the concentrations of the selected preservatives in nutrient broth. Nutrient broth was initially used as it can be easily and accurately adjusted and controlled in terms of composition, and allows more rapid growth than is observed in PCA. A combination of salt (sodium chloride), sorbic acid (in the form of potassium sorbate), nisin and lysozyme was selected as stress factor. The inhibitory effect of these preservatives was then observed in the high-moisture nutrient broth at pH 7 (the optimum condition for spore of C. sporogenes to germinate) at 37ºC for eight weeks. It was found that lysozyme did not have a significant inhibitory effect on C. sporogenes in combination with salt, potassium sorbate and nisin. Therefore, the inhibitory effect of salt, sorbic acid and nisin at two different pHs (5.5 and 7) were subsequently evaluated in the nutrient broth at 37ºC for eight weeks. The probability of growth of C. sporogenes was modelled as a function of the concentrations of these selected preservatives at each pH. The results demonstrated that a combination of salt, nisin and potassium sorbate at relatively low concentrations can be used to inhibit growth. The inhibitory effects of the preservatives were pH dependent and their inhibitory effect is higher at pH 5.5. The developed models were validated using a fresh data set. Finally, the applicability of the developed model was checked in high moisture PCA. The results showed that the developed broth model underestimated the probability of growth in the PCA. Therefore, a specific probability of growth model was developed for the PCA using the PCA instead of nutrient broth as the growth medium. This model accurately predicted the probability of growth of C. sporogenes in the PCA for given combinations of preservative concentrations. The model developed for PCA allows the relative levels of preservatives to be easily quantified without the need for time consuming and expensive experimental work. The model would have limitations in the case of strongly varying formulations, since minor changes in processed cheese formulation or its production, could significantly alter its ability to support toxin production. Therefore, the model is applicable only to PCAs that have formulations similar to that used in this study. The general approach described in this thesis could be applied in the development of other high moisture, low acid foods.

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  • The relationship between self-regulated learning and the use of online portfolios in an online learning environment : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Education at Massey University, Manawatu, New Zealand

    Sasai, Lalida (2015)

    Doctoral thesis
    Massey University

    Self-Regulated Learning (SRL) theory provides an explanation for how learners control and direct their thoughts, feelings, and actions in relation to their learning goals and is considered to be an important requirement for successful learning. Using online portfolios is believed to enhance SRL skills. This longitudinal study conducted over one academic year examined postgraduate students’ SRL skills in relation to their use of online portfolios within an online learning environment, and how they perceived the value of online portfolios. Factors that affected students’ self-efficacy beliefs and perceptions of their ability to be successful in using online portfolios were also studied. A mixed methods research design with an explanatory sequential approach involving three phases was used in the study. In the first phase, at the start of academic year, a questionnaire was used to assess students’ initial SRL skills and their perceptions of the usefulness of online portfolios. Sixty-four students participated in this phase. Two SRL groups comprising students with high and low SRL scores were drawn from this sample. A three-person sub-sample of each SRL group was interviewed in the second phase in order to examine in greater depth the nature of SRL skills for those with high and low SRL scores. For the third phase, a follow-up questionnaire was used towards the end of the academic year to examine whether students’ SRL skills and their perceptions of the usefulness of online portfolios changed over the period of their enrolment in the postgraduate course. For this third phase, 92 students participated. The results revealed that SRL had a strongly positive relationship with students’ perceptions of the usefulness of online portfolios and the relationship between the two variables over time was reciprocal  that is, both constructs influenced each other. The results also showed a significant increase in students’ reported SRL skills and in their positive perceptions of the value of online portfolios over the year. Students attributed the increase in these two variables to using online portfolios to help set their own learning goals, control their own learning, and reflect on their learning. They identified a range of factors, including course support, motivation, peer support, and lecturer support, as helping them to construct and use their online portfolios. However, they identified lack of technology skills and time constraints as the main problems in constructing and using their online portfolios. The findings of the present study indicated that students’ skills across the three aspects (forethought, performance, and self-reflection) of SRL, the three stages of the use of online portfolios (collection, selection, and reflection), and the three elements of learning (personal, behavioural, and environmental) were interrelated. Such findings have important implications for students and university course coordinators to make better use of online portfolios, and for teaching and learning in a university online learning context, particularly in relation to the use of online portfolios as a tool for both storing (product) and reflecting (process) on artefacts of learning. This contribution in turn will help students to better regulate their learning behaviour.

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  • Efficiency of the banking system in Vietnam under financial liberalization : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Banking Studies at Massey University, Manawatu Campus, New Zealand

    Ngo, Dang Thanh (2015)

    Doctoral thesis
    Massey University

    The thesis reviews the (triangular) relationship between financial liberalization, economic growth, and banking development. It points out the causality effect where financial liberalization could improve the efficiency of the banking sector, but on the other hand, it also could lead to instability in the banking system. The recent Global Financial Crisis raised questions as to how and at what level financial liberalization could be done so that for banking development, improvements are achieved but instabilities are avoided. The thesis answers these questions employing a new sample (the Vietnamese banking system), covering a long period (1990-2010), and consistently applying different approaches and models. Three different approaches are used, namely ratio analysis, stochastic frontier analysis (SFA), and data envelopment analysis (DEA). Our findings suggest that the performance of the Vietnamese banking system generally improved during 1990-2002, worsened during 2003-2008, and recovered in 2009-2010. However, there was no statistical association between this performance and the regional or global financial crises in 1997 and 2007/08. Although future studies are needed (since our sample was small and thus, the results may not be accurate), there was evidence that the state-owned commercial banks were less efficient than the joint-stock commercial banks and hence, equitization of the state-owned commercial banks should be speeded up in order to transform their ownership, reducing their size, and improving their performance. There are consistencies between these approaches in terms of defining the efficiency scores, trends, and best and worst performers. Our findings also suggested that the timetrend- DEA, as well as the Fisher Index-DEA models, could be an alternative to the panel- DEA and Malmquist Index-DEA models since they could provide additional information on the performance measures, especially in case of data limitation. However, we could not find consistent results between the ratio analysis model and the ratio-based DEA ones (Panel- and Malmquist Index-DEA) in terms of scores, trends, and determinants.

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  • The good fight : power and the indigenous struggle for the Manawatū river : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Resource and Environmental Planning at Massey University, Manawatū, New Zealand

    Bennett, April Leanne (2015)

    Doctoral thesis
    Massey University

    Power is the central theme of this research. This thesis examines how power structures iwi contributions to freshwater planning and decision-making. Power has received little attention in literature on Māori and natural resource planning, even though it reproduces and potentially transforms existing inequalities among Māori, other actors and planning institutions. In failing to analyse power, scholars have left a significant gap in the literature. In New Zealand, the deleterious effects of agricultural expansion on water have significant implications for iwi, as water is linked to tribal identity and mana. Both past and current generations have struggled to protect water. Contemporary strategies to restore degraded water bodies and reclaim mana, as control and authority, over water include co-management arrangements. Simultaneously, Government has taken an enthusiastic, uncritical stance to promoting collaboration as an approach to freshwater planning, including iwi as one among multiple actors. In this pro-collaboration climate, however, power has been ignored. So, this research asks: How does power structure iwi contributions to freshwater planning and decision-making? To answer this question, a case study was undertaken of the Manawatū River, a highly degraded water body in the lower North Island of New Zealand. Two main methods were used to collect data: semi-structured interviews with 13 key informants and an analysis of 214 documents, including 180 newspaper articles. To interpret the data, the theoretical framework used Pierre Bourdieu’s concepts of field, capital and habitus. The research found that power structures all contributions to freshwater decisionmaking into a hierarchy, with iwi contributions typically marginalised. The hierarchy is a colonial legacy which continues to be reproduced in multiple ways. So, while collaboration, as advocated by the Crown, has some benefits for iwi, it will not help re-structure this hierarchy to enable iwi to regain control over water. Other strategies, such as Treaty of Waitangi settlements, are liable to be more effective. This finding implies that iwi must assess whether co-management or collaboration strategies will enable them to reshape power imbalance. Gaining power is critical to transform inequality, reclaim authority and restore the mauri of water for future generations.

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  • Workplace bullying in the New Zealand nursing profession: the case for a tailored approach to intervention : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Human Resource Management at Massey University, Albany, New Zealand

    Blackwood, Kate Marie (2015)

    Doctoral thesis
    Massey University

    This thesis explores intervention in the workplace bullying experiences of New Zealand hospital nurses. Workplace bullying is a recognised problem internationally, and nursing is a high risk profession for such ill-treatment. With existing studies mapping the workplace bullying terrain, the research field is now moving towards how best to manage the problem. Recent research has identified numerous barriers to effective intervention and, as a result, existing studies recognise the need for a different approach that considers the impact of the work environment on intervention efficacy. The aim of this study is to understand how the work environment influences intervention in workplace bullying. Specifically, the research was guided by two questions: i) how do targets of workplace bullying in the New Zealand nursing profession represent their intervention experiences? and ii) how do work environment factors impact on the intervention experiences of targets of workplace bullying in the New Zealand nursing profession? The findings of this research are informed by 34 semi-structured interviews with targets of workplace bullying and three focus groups with organisational representatives responsible for bullying intervention. Thematic analysis of the interviews resulted in the development of an holistic intervention process model portraying how targets represent their intervention experiences. Subsequent thematic analysis of the interview and focus group data identified how a number of contextual and work environment factors influence the intervention process model. The model explains three key stages of intervention, namely identification of a bullying experience, reporting and intervention agent response, and how each of these stages influences the final outcome of an intervention experience for targets of workplace bullying. Specifically, the cyclical and iterative way in which these stages are experienced by targets is emphasised. A number of contextual and work environment factors that are barriers or facilitators in the intervention experience are explained. To explain the influence of contextual factors, five types of bullying experience are presented, each with a unique set of features that influence intervention in different ways, emphasising the heterogeneous nature of workplace bullying. Work environment factors are also identified as influencing the intervention process, providing empirical support for an extension of the work environment hypothesis to intervention in workplace bullying experiences. Tailored intervention strategies are recommended in light of the findings.

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  • Māori women, health care, and contemporary realities : a critical reflection : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Health) at Massey University, Wellington, New Zealand

    Parton, Beverley May (2015)

    Doctoral thesis
    Massey University

    Māori women, health care and contemporary realities is a critical reflection on the context of my nursing practice, a Pākehā nurse employed by Kokiri Marae Health and Social Services (KMHSS), Lower Hutt, Aotearoa New Zealand. In addressing the disparities Māori experience KMHSS has the motto, “Committed to the holistic development of whānau, hapū, and iwi”. The research aimed to explore from the experiences of urban Māori women, influences on their health and health care engagement. Kawa Whakaruruhau, the critical nursing theory of cultural safety for Māori health care, informs a qualitative approach, a human rights perspective, with its categories of difference, power, and subjective assessment. In turn, whiteness theory, with its categories of white (and not so white) power and privilege, informs Kawa Whakaruruhau. The women’s stories were received in an unstructured interview method and analysed thematically. The historical, social, cultural, economic, political, racial and gendered factors contributing to Māori women’s health and health care engagement are presented as a geography of health, and as landscapes past, present and future. Landscapes past tell of the disruption of the whakapapa connections of land, language and health by the historical and ongoing processes of colonisation. Landscapes present tell of health care places and spaces that by their policies, cultures, structures, and health professional practice, network and connect to include or to exclude Māori women and their families. Landscapes future are envisioned by the women as they remember what is and has been, and then imagine for themselves and at times succeeding generations, what they require as Indigenous to be central to health care. The women imagine what they need to parent for their children to have a good life; they imagine a therapeutic landscape. (In)authentic identities are presented as chronicities of risk, inhabiting disease and poverty. The women expressed authentic mana wāhine identity uniquely and heterogeneously. Recommendations have been made for nursing practice, research site and research.

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  • Doing good and feeling well : understanding the relationship between volunteering and mental wellbeing in older adult populations through the application of a social-cognitive theory of depression : a thesis presented in partial fulfilment of the requirements for the degree of Doctorate in Clinical Psychology at Massey University, Albany, New Zealand

    Cooper, Louise Elizabeth (2015)

    Doctoral thesis
    Massey University

    Previous research indicates that volunteering can improve positive psychological wellbeing, and protect against the onset of depressive symptoms amongst older adults. However, the mechanisms at play in the relationship remain unclear. This research project analysed two data sets in order to test the predictions of a social-cognitive theory of depression as it applies to the volunteering-psychological wellbeing relationship. A social cognitive theory of depression (as described by Oatley and Bolton (1985)) suggests that older adults are susceptible to symptoms of depression and reduced psychological wellbeing when difficult life events limit their ability to maintain social roles that have previously facilitated investment in valued facets of their self-concept. Therefore, volunteering may compensate for such role losses by enabling older adults to continue to contribute to their sense of self through their volunteering role, and subsequently protect them from the effects that such role-loss may have on their psychological functioning. Using longitudinal data from a New Zealand-based sample, this research illustrates that older adults who have relatively poorer physical health are more likely to be protected from experiences of depressive symptoms as a result of consistently volunteering than those who experience higher levels of health. Analyses of longitudinal data also provide some evidence that employment status may moderate the impact of volunteering consistency on protection against symptoms of depression. In addition, analyses of cross-sectional data demonstrate a relationship between contributions to self-concept through the enactment of social roles, and better psychological wellbeing. This research also suggests that the extent to which negative life events limit a person’s ability to invest in their sense of self is related to psychological wellbeing outcomes. Finally, it is suggested that the amount of investment in self-concept facilitated by a volunteering role is related to psychological wellbeing. However, investment in self-concept through volunteering was not shown to moderate the relationship between pertinent life stressors, and psychological wellbeing. To a large extent, these findings align with a social-cognitive theory of depression (Oatley & Bolton, 1985), but they raise questions about the way that compensatory coping through social role changes has previously been theorised.

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  • Essays on foreign exchange rate predictability: a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Finance at Massey University, Palmerston North, New Zealand

    Raza, Ahmad (2015)

    Doctoral thesis
    Massey University

    This dissertation consists of three interconnected essays on currency return predictability. The first essay investigates whether momentum or reversal is the dominant phenomenon in weekly currency returns. Using a broad basket of 63 emerging and developed market currencies in 16 short-term (1- to 4-week) look-back and holding period strategies, I find strong evidence in favour of cross-sectional momentum rather than reversal in weekly currency returns. Short-term momentum returns are statistically significant and are over 8% p.a. Moreover, the returns increase with an increase in the look-back period. I show these returns are higher in the earlier sub-period but they still exist in the most recent sub-period. Breakeven transaction costs range from 2 to 97 basis points. Furthermore, I find that short-term currency momentum returns are higher during business cycle expansions and during periods of depreciation of a basket of currencies versus the USD. Finally, robustness checks and regression analysis show that currency momentum returns are not linked to carry trade returns and are reduced by rising volatility in the foreign exchange market. The second essay examines the profitability of the 52-Week high momentum strategy proposed by George and Hwang (2004) in the foreign exchange market. I show this strategy, which is more profitable than price momentum in stocks, is not profitable in the foreign exchange market using a large basket of 63 currencies. The related 52-week low and the 52-week high minus low strategies also fail to generate significantly positive returns. On further exploration of the causes of low returns to these strategies, I find the presence of non-independently floating currencies in long and short portfolios is a contributing factor. Excluding these actively managed currencies helps in improving 52-week high strategy returns. Moreover, shortening the length of the strategy look-back period to 4- and 12-week also leads to minor improvement in returns, however, the improvement is not significant. Furthermore, I show that accounting for the timing of the 52-week high event also results in minor improvements in 52-week high strategy returns. Finally, I find that the 52-week high currency strategy does not generate positive returns in any phase of the business cycle and during UP or DOWN state of the FX market. The third essay studies the profitability of currency value strategies by running a horse race of four measures of currency value including real exchange rate levels, 5-year change in the real exchange rate, the Purchasing Power Parity and the Big Mac Index. I find the real exchange rate level based strategies outperform all other strategies at shorter holding periods by generating annualized excess returns of up to 7% and the real exchange rate change strategies perform the best at longer (1- to 12-month) holding horizons. I show that a composite strategy which is based on all four value measures is highly profitable and yields average excess returns over all horizons up to 10% p.a. Furthermore, the returns to value strategies significantly improve when only non-independently floating currencies are used. I find that high yielding currency value strategies have considerably higher breakeven transaction costs starting from 58.5 basis points per one way trade due to low annual portfolio turnover. Moreover, the results indicate that real exchange rate levels and real exchange rate change strategies generate higher returns during expansionary phase of the US business cycle and during times of US dollar depreciation. Finally, detailed regression analysis shows that currency value returns exist independently of the currency carry trade returns and are not explained by a broad list of key macroeconomic variables.

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  • The "manufacture" of news in the 1993 New Zealand general election : a thesis presented in partial fulfilment of the requirements for the degree of PhD in Human Resource Management at Massey University

    McGregor, Judith Helen (1995)

    Doctoral thesis
    Massey University

    The news media's role in general election campaigns in New Zealand remains mysterious because few indigenous research antecedents inform the debate about the democratic function of journalists reporting election campaigns. This study analyses the creation of news by reporters during the 1993 New Zealand general election campaign and examines the relationships between journalists, politicians and third party sources which impact on political communication. The analysis leads to a discussion of the role of the news media in reporting election news. The notions that news is created by journalists and through relationship between journalists, politicians and third party sources are central to the study. The concept that news is "manufactured" or socially constructed is explained in the introductory chapter and linked to theoretical perspectives in the literature review in Chapter Two. The two broad research questions which the study answers are: 1. how was the news manufactured during the 1993 New Zealand election campaign? 2. what does this mean for the "dialogue of democracy" (Taylor, 1992)? The manufacture of news is examined from three perspectives in the research. These can be called the "doing" perspective which employs action research methodology, the "watching" perspective which uses participant observation methodology and the "measuring" perspective utilising content analysis. The research notes the failure of "any particular holistic paradigm" to sweep the field of political communication and employs "ground-up paradigm building" by carving out broad research problem areas and examining them through the use of appropriate research methodologies (Bennett, 1993, p.182). The objectives of the action research project were twofold. First, to assist an individual political candidate contesting the election to develop systematic processes to use the news media to raise the candidate's profile. Second, to increase the level of understanding by the political candidate of news media processes and news concepts such as newsworthiness, candidate accessibility and news angles so she could utilise the knowledge to generate news and photographic opportunities. The findings revealed that the political candidate perceived that her level of understanding of news processes was enhanced through the action research. The study found, too, that a systematic process of source relationship was cultivated between the political candidate and journalist, which in principle enhanced the democratic function of the news media as a platform for political debate. The action research project, was, however, bound by the prevailing climate of political rhetoric with all its shortcomings. The participant observation methodology explored the nature of the contest between the triumvirate of political candidates as sources, journalists and third party sources such as "spin doctors". A second research question examined whether reporters seek to reassert their role in such a way as to influence the news when traditional journalistic autonomy is threatened. The findings showed a complex, shifting contest for control over knowledge and power in the making of news. This contest was characterised by features such as the increased sophistication of third party sources actively intervening in news processes, by strategic utilisation of "new" news formats by politicians and by journalists vigorously defending their status and enlarging their role. The impact of the findings on democratic journalism were examined using Golding's (1990) suggestion of a revival of the notion of citizenship, "to what degree and in what ways are people denied access to necessary information and imagery to allow full and equal participation in the social order?" (p.98). The third methodology, content analysis, tested Edelstein, Ito and Kepplinger's (1989) theory of news content using a cognitive construct, the problematic situation. The results confirmed a larger interpretive as opposed to purely descriptive role for metropolitan newspaper journalists reporting news in the 1993 general election campaign in New Zealand. Over 70% of election campaign issues in the period sampled were defined problematically and negatively with a high reliance on references to loss of value and conflict. The findings have implications for how political candidates could and should tailor their political messages. Overall the results taken together have fundamental implications for the "dialogue of democracy" (Taylor, 1992). They disclose a powerful dilemma about the manufacture of news in the 1993 New Zealand general election. The expanded influence of the news media has not been accompanied by a reassessment of what it is the news media should be doing in election campaign reportage. Reformative suggestions are made in the final chapter of the study and the implications for political journalism in a democracy are discussed.

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  • Remediation of New Zealand sheep dip sites using biochar and phytoextraction technologies : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Soil Science, Institute of Agriculture and Environment, College of Sciences, Massey University, Palmerston North, New Zealand

    Gregory, Samuel (2013)

    Doctoral thesis
    Massey University

    The practice of sheep dipping, which subjected livestock to inorganic and organic agricultural pesticides to eradicate pests such as lice and keds, is a historic practice; sheep dipping is no longer practiced in New Zealand today. Animals would be submerged in solid structures known as dips containing chemicals such as arsenicals and organochlorines with the leftover solution pumped onto surrounding soil. The use of pesticides such as these is now banned by law due to their persistence in the environment. Today an estimated 50,000 contaminated sheep dip sites exist in New Zealand representing perhaps the countries’ most significant, but understated, environmental challenge. To determine whether this historic agricultural practice had led to contamination of the environment, an investigation into the extent of contamination resulting from sheep dipping at a known historic dip site in Te Mahia, New Zealand was carried out. Characterisation of the site by arsenic soil concentration mapping revealed that 500 m2 of agricultural land has been contaminated with this metalloid and that arsenic exists at varying high concentrations through the soil profile. Environmental risk from these historic pesticides was established by analysing plant and water samples below the dip site. Staple Maori food varieties such as watercress were significantly contaminated with arsenic while water samples taken from the stream below the dip returned spiked arsenic concentrations. Based on this, it was justified that arsenic/organochlorine contamination would need to be managed to reduce their effect on these food sources. The design of a coupled remediation strategy using phytoextraction and biochar was utilized to reduce remediation times and is the basis of this thesis. Contaminated soil from the site was removed and amended with two types of biochar produced from willow feedstock. These biochars, known as 350°C and 550°C biochar were added into the soil at application rates of 30 t ha-1 and 60 t ha-1. During a series of 180 d glasshouse trials, the phytoextraction of arsenic into Lolium perenne (ryegrass) shoot tissue was analysed along with growth parameters of shoot and root biomass and corresponding response to arsenic at the molecular level. In soil; microbial activity, soil bacterial community, organochlorine concentration, and element dynamics were analysed as a function of biochar amendment. Soil microbial activity, analysed using the dehydrogenase assay (DHA), was significantly increased (P<0.05) in chlorophyll content in response to the total arsenic concentration in ryegrass shoot tissue grown on contaminated soil. The observed increases in activity of SOD, APX and steady CAT activity is suggested to be efficiently catalysing the production of harmful ROS in this soil. A 6-month field investigation into the effect of biochar amendment on the extraction of arsenic into a high biomass crop (Salix sp) resulted in significant increases of arsenic in stem biomass as a function of biochar amendment. When data was extrapolated to predict results of a long-term field trial and scale under willow treatment (stem) it was calculated that over 67.7 g of arsenic could be extracted in soils amended with 350°C biochar compared to 5.9 g extracted under control treatment. This could result - assuming a similar rate of extraction with time - in levels of arsenic concentration in soils reaching background concentrations in as little as 6 years, a reduction in remediation times of 92%.

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  • Repetition as revision : explored through the revision of place in Jackie Kay's Fiere, Kathleen Jamie's The Tree House and Crane, a creative composition by Lynn Davidson : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in English at Massey University, Palmerston North, New Zealand. EMBARGOED until 1 September 2017

    Davidson, Lynn (2015)

    Doctoral thesis
    Massey University

    This thesis examines anaphora, parallelism, and repetends, and asks if and how these techniques of repetition allow for negotiation among meanings, contexts and possibilities in contemporary poetry. The thesis is comprised of two sections, creative and critical, with a seventy percent creative and thirty percent critical split. The critical study is based on a close analysis of anaphora and parallelism in Jackie Kay’s Fiere (2010) and repetends in Kathleen Jamie’s The Tree House (2004), while repetition is explored creatively through Crane, an original collection of poetry shaped and informed by the critical research. Crane uses techniques of formal repetition to enquire into cultural and emotional links to place, and the impact of return journeys to significant places on a reimagining of place and self. There are five sections in Crane, each of which uses repetition slightly differently to engage with questions of movement between places. The collection uses repetition to explore how ‘going back’ can be a powerful part of the process of revising identity and integrating change. The critical portion argues that Scottish poets Kay and Jamie emphasise the effects of repetition to explore the perceived dichotomy of having deep roots in a national poetic tradition yet questioning nationalistic ideologies that can come with that tradition. Kay uses the highly structured techniques of anaphora and parallelism to layer possibilities for place and belonging; Jamie’s use of the less formally structured technique of intertextual repetends draws attention to the responsive and mutable nature of language in order to ask questions about compositions of place within the natural world. The thesis argues that repeated words alter in meaning due to the influence of syntactic environment. Further, it claims that as the repeated word moves through different syntactic contexts with the resulting alterations in aspects of its meaning, it can develop figurative meaning and provide possibilities for re-imagining some established narratives – specifically for this thesis, concepts of identity and place.

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  • Sensing and signalling mechanical stress during intercalary growth in Epichloë grass endophytes : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD) in Genetics at Massey University, Manawatu, New Zealand

    Ariyawansa, Kahandawa Geeganaarachchige Sameera (2015)

    Doctoral thesis
    Massey University

    Epichloë festucae is an agronomically important seed-transmitted endophytic fungus that grows symbiotically within the intercellular spaces of temperate grass species. This fungus has previously been shown to undergo hyphal intercalary growth during host leaf colonization, a highly unusual mechanism of division and extension in non-apical compartments in vegetative hyphae, as an adaptation to colonise rapidly elongating host cells in the developing leaf. However the exact mechanism that triggers intercalary growth was not known. In this study I aimed to test the hypothesis that intercalary growth is stimulated by mechanical stretch imposed by attachment of hyphae to elongating host cells, and that this stress is sensed by mechano-sensors located on hyphal membranes. To test this hypothesis a novel technique was designed and optimised to stretch fungal hyphae under in vitro conditions. Investigation of un-stretched hyphae showed that de novo compartmentalization occurs in sub-apical compartments of E. festucae hyphae according to a compartment length-dependent hierarchy. Subjecting these sub-apical compartments to mechanical stretching showed that hyphal compartment lengths can be increased while maintaining viability, provided that the stretch is within tolerable limits. It further showed that the stretched compartments undergo de novo compartmentalization (nuclear division and septation) similar to un-stretched hyphae but at a significantly higher rate, fulfilling the basic requirements for intercalary growth. E. festucae WscA and MidA, which are orthologues of a yeast cell wall stress and a stretch-activated calcium channel protein respectively, were functionally characterized in order to test the possible involvement of these mechano-sensors in intercalary ii growth. Their roles in general hyphal apical growth, cell wall construction and integrity maintenance during growth in culture were confirmed. The limited ability of ΔmidA mutants to colonise developing leaves indicated a possible role in intercalary growth, while ΔwscA mutants showed wild-type levels of host colonization. In future, the ΔmidA and ΔwscA mutants will be subjected to mechanical stretch in vitro to further understand their roles in mechano-sensing and intercalary growth. Given the possible involvement of the stretch-activated calcium channel MidA in intercalary growth, a successful technique was developed to study calcium signalling and distribution in E. festucae using the genetically-encoded calcium sensor GCaMP5. Investigations revealed the presence of MidA-driven Ca2+ pulses confined to the hyphal tips with unique signatures of temporal and spatial dynamics generated by influx of Ca2+. The presence of active sub-apical Ca2+ uptake systems were confirmed, manifested as occasional Ca2+ pulses in sub-apical compartments that seemed to increase in frequency with mechanical perturbation, indicating a potential crucial role in mechanical stress-driven intercalary growth. In conclusion a prospective model for intercalary growth in the leaf expansion zone is proposed. Mechanical stretching of hyphae results in increased compartment lengths, accompanied by compartmentalization in sub-apical compartments that allows hyphae to extend along their length. Membrane distortion due to stretching activates MidA, triggering a calcium signalling cascade to stimulate cell wall synthesis and other cellular processes.

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  • Understanding bacterial adaptation to aerobic and anaerobic environments through experimental evolution and whole genome analysis : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Genetics at Massey University, Palmerston North, New Zealand

    Finn, Thomas (2014)

    Doctoral thesis
    Massey University

    Facultative anaerobic organisms have the metabolic versatility to grow in both aerobic and anaerobic environments. However, molecular mechanisms that underpin adaptation to anaerobic environments are not well understood. This study aims to understand how the facultative anaerobe, Escherichia coli, adapts to environments that vary in oxygen content. An experimental evolution experiment was conducted in which replicate lineages were established from a preevolved clonal culture of E. coli REL4536. Lineages were serially sub-cultured for 4,000 generations within strict aerobic and strict anaerobic environments, and a treatment that fluctuated between the two environments. Significant increases in the relative fitness of lineages exposed to anaerobic conditions were observed, whereas the relative fitness of lineages in aerobic conditions did not increase, likely as the ancestor had been pre-adapted to aerobic growth. Mutations that arose during evolution were identified by genome sequencing randomly-selected clones from each lineage at 2,000 and 4,000 generations. Traits that contributed to adaptation were predicted via the occurrence of independent mutations affecting common traits among lineages. Adaptation to the anaerobic environment was facilitated by modifications to anaerobic fermentation and the inactivation of virulence genes, whereas in the aerobic environment, mutations predicted to confer a growth advantage in stationary phase were observed. The evolution of generalists involved traits that were similar to those found in both aerobic and anaerobically evolved lineages, as well as the deletion of cryptic prophages from the genome and modifications to amino acid transport. Phenotypically distinct small colony morphotypes (SCM) arose within anaerobic lineages and two separate adaptive pathways are hypothesised for this divergence. SCM1 were capable of stable coexistence with co-evolved cells of typical colony morphotype, most likely through an acetate crossfeeding mechanism. In contrast, SCM2 was able to out-compete the ancestor within 14 days, despite exhibiting a lower growth rate than the ancestor. SCM2 likely evolved the ability to inhibit the ancestral strain through a contact dependent inhibition mechanism, as evidenced by a mutation in glgC. This thesis demonstrates the complex nature of adaptation to anaerobic environments, as revealed by experimental evolution and whole genome sequencing.

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  • Benchmarking agri-food supply chains : a case of Pakistan and New Zealand milk systems : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Logistics and Supply Chain Management at Massey University, Palmerston North, New Zealand

    Moazzam, Muhammad (2015)

    Doctoral thesis
    Massey University

    Businesses are now operating as parts of collaborative networks sharing skills and information synergistically to offer superior value to the customers. In order to stay competitive or surpass competitors, businesses benchmark their performance against industry leaders or best-in-class competitors. A benchmarking study aimed to examine the causes of poor performance of the milk supply chain in Pakistan was undertaken. Fo this purpose the performance of key players of milk supply chain in Pakistan was benchmarked against those of New Zealand. An extensive review of literature was conducted with the objective to choose an appropriate performance measurement framework. For this purpose existing frameworks were evaluated against five criteria characterising performance measurement in agri-food supply chains and not a single framework qualified. This research gap was abridged by developing a framework based on supply chain operations reference (SCOR) model but with certain modifications to food quality. Pragmatic approach was used to select appropriate research design. Cross-sectional data was collected using survey strategy. A total of 490 respondents were accessed through personal interviews (430 in Pakistan) and online questionnaires (60 in New Zealand). Samples were drawn using a combination of multi-stage and purposive sampling methods. A three-step approach was proposed to address the individual objectives of the overall study. The first-step was to conduct value chain analysis of both the milk supply chains. The second-step was to measure the performance of key players of both the milk supply chains using the performance measurement framework developed as a result of literature review. The third-step was to perform gap analysis of the SCOR metrics for key players of both the milk supply chains and suggest appropriate policy measures for the improvement of milk Supply chain in Pakistan. The data were analysed with statistical package for social scientists (SPSS) and Microsoft Excel. The value chain analysis was performed to explore the benchmarking milk supply chains as well as to gauge the level of vale addition. The value chain maps discussed the primary functions, activities, operators, facilitators, and enablers in the milk supply chains in Pakistan and New Zealand. Moreover, the analysis of value distribution along the entire chain indicated that the informal chain of milk (unprocessed milk) in Pakistan had 22.39% ex-farm gate value addition, with the largest (almost 82%) share of the value captured by the dairy farmers. Whereas, the formal chain of milk (processed milk) iii in Pakistan had 104.23% ex-farm gate value addition, with the largest (51%) share of the value captured by the dairy farmers. The milk supply chain in New Zealand had 216.83% ex-farm gate value addition, with the largest (55.6%) share of value captured by the retailers. The findings of the gap analysis were:  Pakistani dairy farmers under performed in supply chain reliability, cost of production, and return on working capital as compare to NZ dairy farmers. The majority of the Pakistani dairy farmers were smallholders and due to diseconomies of the scale of their operation they could not afford modern dairy farming technologies such automatic milking, milk storage at controlled temperature, and other precision dairy farming (PDF) technologies.  The Pakistani milk collectors underperformed in perfect order fulfilment, flexibility and cost of milk sold and outperformed in value at risk, SCM cost and return on assets as compared to NZ dairy companies. The Pakistani milk shops underperformed in cost of milk sold and outperformed in order fulfilment cycle time, flexibility, value at risk, SCM cost and return on assets as compared to NZ dairy companies. The Pakistani dairy companies underperformed in perfect order fulfilment and flexibility as compared to NZ dairy companies. On the basis of findings of the value chain analysis, SCOR analysis, and gap analysis, promotion of agricultural cooperatives as a phased-out medium to long term policy intervension was recommended.

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  • Understanding matakite : a Kaupapa Māori study on the impact of matakite/intuitive experiences on wellbeing : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Māori Studies at Massey University, Papa-i-ōea, Aotearoa

    Ngata, Ronald Spencer (2014)

    Doctoral thesis
    Massey University

    This thesis is a response to expressions of concern from within Māori communities and also from within mental health that some Māori who are diagnosed as mentally ill are actually having spiritual experiences, which in the Māori culture are called matakite (among other terms). The thesis explores this issue from a Kaupapa Māori perspective, which enables a multi-layered, culturally resonant, exploration and analysis of the health issues that arise in relation to matakite. Thus, while exploring the nature of the experience, the thesis also explores the impact of social, cultural, political, and economic factors upon the wellbeing of people experiencing matakite, and which have hindered the use of the Māori spiritual knowledge-base as a health resource. It is expected that this thesis will increase understanding of the nature of the experience and its relevance within contemporary Māori society, and therefore contribute to the reduction, and ideally elimination, of the misdiagnosis of matakite as symptomatic of a mental disorder. An exploration of the literature reveals a history of ignoring or misunderstanding experiences of a spiritual nature by mainstream Western mental health researchers, clinicians, and policy makers. However, new interest in this field is emerging, and attention has been turned to the development of bio-psycho-socio-spiritual models. Nevertheless, Western biomedical frameworks continue to dominate the discourse and practice in mental health, despite decades of calling for a more integrated approach from many health disciplines, researchers, indigenous communities, and mental health consumers. viii The study reveals new understandings about the nature of matakite experiences, which may support efforts to distinguish between matakite and pathology. Multiple factors are identified as impacting upon the wellbeing and health of people experiencing matakite. The impact of social and cultural factors, as well as the politics of mental health, upon the wellbeing of matakite are identified, and possible strategies for enhancing and protecting wellbeing around matakite experiences are discussed. To this end the study challenges the norms and structures in mainstream Western mental health and highlights how traditional Māori knowledge about matakite can be used as a resource for mental health in Aotearoa New Zealand.

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  • The microbial ecology of Campylobacter jejuni in New Zealand within a spatial-temporal framework : a thesis presented in partial fulfilment of requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Manawatu, New Zealand

    Binney, Barbara Mary (2015)

    Doctoral thesis
    Massey University

    Campylobacter jejuni (C. jejuni) is an important cause of gastroenteritis internationally; it is a complex bacterium carried by multiple hosts, showing phenotypic and genotypic variation. This thesis systematically examines the molecular ecology and evolution of C. jejuni in New Zealand from the levels of population movement, phenotype, genome and metabolism. First, the demographic history of cattle, sheep and poultry importations into New Zealand (1860- 1979) was quantified. Australia was the most common reported source of cattle sheep and poultry, with large numbers of cattle and sheep being imported in the 1860s, and large numbers of poultry imported from the 1960s onwards. This suggests the population structure of cattle and sheep and the microbial organisms they carried may exhibit a founder effect. The second level investigated the phenotypes of related sequence types (ST) with generalist and specialist lifestyles and compared them at 42°C and 22°C on the basis of carbon source utilisation in Biolog phenotypic microarrays. The isolates utilised a total of 29 carbon sources in a pattern that clustered them together on the basis of ST at 42°C more than lifestyle and host. At 22°C they utilised a limited palette of carbon sources (9) related to the tricarboxylic acid cycle (TCA). The third level, used genomic comparisons to identify a putative new species C. sp. nov. 4 spp. in the Australian purple swamphen (Porphyrio porphyrio melanotus). Overall, the pattern of relationship between isolates associated with the pukeko (Porphyrio porphyrio melanotus), takahe (Porphyrio hochstetteri) and the Australian swamphen isolates suggested a recent common ancestor and then divergence after separation. Despite high levels of recombination in C.jejuni, the genomes grouped by clonal complex and ST, this suggests there are factors restricting regular recombination between more distant C. jejuni STs. The draft genomes for the wild-bird and agricultural-related isolates clustered by lineages in a host(s). The fourth level involved the comparison of C. jejuni metabolic pathways (subsystems) to identify host association. Type VI secretion system, Coenzyme A biosynthesis and Campylobacter spp. iron metabolism were identified as important pathways in distinguishing between wild-bird and livestock associated isolates.

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  • The psychological impact of resource gains and losses in an ageing population from the perspective of conservation of resources theory : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Clinical Psychology at at Massey University, Palmerston North

    Hooks, Rachel Anna (2015)

    Doctoral thesis
    Massey University

    The aim of the current study was to examine a series of hypotheses and questions derived from Hobfoll’s (1988) conservation of resources theory (COR) using existing longitudinal data from 1,119 55-70 year-old participants of the Health, Work and Retirement Study parent study (Alpass, 2009). The years from mid-life through retirement into older adulthood are signified by change and adjustment. COR theory predicts these years are also a time of significant stress as personal and material resources are depleted. This main hypothesis of this study predicted that losses in valued resources over time would result in loss of psychological wellbeing over the same period. Additionally, other central COR principles were examined such as the potential role of resource gain in alleviating the impact of other resource losses, and the potential for resource losses or gains to spiral. Hobfoll’s suggestion that losses and gains increase respective vulnerabilities and opportunities for further losses and gains were also explored, as was his idea that resources correlate or travel together as a “caravan”. Analyses: Chi-square and logistic regression were used as the general strategy for testing all hypothesized main and interaction effects as well as for exploring research questions. Resources examined for the potential impact of changing levels on psychological wellbeing were economic standard of living, physical health, and social support. Results: Losses in economic standard of living were associated with clinically significant loss in psychological wellbeing, with large losses associated with increased odds of loss in psychological wellbeing at a rate over four times that of participants who did not experience such loss. Gains in economic standard of living were also associated with gains in psychological wellbeing, but to a lesser degree. Similarly, loss of social support over the same period was associated with loss of psychological wellbeing. However gains were not associated with gains in psychological wellbeing. Anomalously, no association was found for losses or gains of physical health on psychological wellbeing. In support of COR, there was evidence that losses impacted psychological wellbeing to a greater degree than sustained low levels of resource ownership, indicating resource loss may have greater impact than sustained “poverty”. Gains in physical health were also found to alleviate the impact of loss of other resources as predicted by COR. No support was found for predominance of loss or gain spirals. Resource ownership levels were far more likely to oscillate than to spiral up or down. Correlations of resources with each other were moderate, providing some evidence of Hobfoll’s resources traveling together. Significance: Results suggested provisional support for the central principles of COR theory linking loss and gain of valued resources to psychological wellbeing. Economic standard of living emerged as a critical and valued resource linked to the relative psychological impact of losses and gains of this resource. This research highlighted limitations in COR theory, in particular an absence of consideration of the differential values resources may have, and the different roles resources might play in maintaining psychological wellbeing. Questions were also raised about the refutability of COR theory. Implications for future research, theory and for the psychological wellbeing of older adults are discussed.

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  • Prevention of plasmin-induced hydrolysis of caseins : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand

    Bhatt, Hemang (2014)

    Doctoral thesis
    Massey University

    Bovine plasmin is a proteolytic enzyme that is naturally present in milk. Plasmin can have a detrimental impact on product quality including proteolysis, age-gelation and bitterness. The activity of plasmin is difficult to control as its precursor, plasminogen, and its activators can survive severe heat treatments such as ultra-high-temperature processing. The aim of this work was to understand and control the plasmin-induced hydrolysis of caseins in milk systems. A sequential approach was used. In the first stage, the effect of substrate modification on plasmin-induced hydrolysis in a pure ß-casein model system was studied; this allowed us to propose a control mechanism to limit the availability of the substrate by protein modification. In the second stage, different protein modifications were applied to a real milk system. In the analysis of this system, the casein micelle structure, whey protein denaturation and whey protein association with the casein micelle were considered. The final stage investigated plasmin-induced dissociation of casein micelles in real milk systems to understand the effect of plasmin activity on gelation and sedimentation in heat-treated milks. Modification of lysine residues on the protein decreased plasmin-induced hydrolysis. Lactosylation had a greater effect than succinylation and transglutamination at the same level of lysine modification. A mechanism for this phenomenon was proposed. Lactosylation involves the attachment of lactose and, in advanced stages, cross-linking, thus modifying lysine and making it unrecognisable to plasmin; in addition, the cross-linking may affect the release of plasmin-generated peptides. Transglutamination also modifies lysine by cross-linking and has a similar effect to lactosylation, but to a lesser extent. In contrast, succinylation modifies the charge associated with lysine, making it unrecognisable to plasmin. Collectively, this knowledge can be used to make protein resistant to plasmin activity. The combined effect of micellar structure and protein modification on plasmin activity was also studied. Calcium chelation and dissociation of the casein micelle increased plasmin activity because of reduced steric hindrance, which made the protein more readily available to plasmin. In contrast, succinylation decreased plasmin activity, which could be attributed to the formation of succinyl-lysine rendering ß-casein unrecognisable to the substrate-binding pocket of plasmin, resulting in a decrease in hydrolysis with an increase in modification. These results indicated the importance of the casein micelle structure as a tool for controlling the activity of plasmin on milk proteins in food systems. The effect of high heat treatment on plasmin-induced hydrolysis was also investigated. A high-heat-treated skim milk (120°C/15 min) was found to have greater resistance to plasmin activity than non-heated skim milk. Both whey protein association with the casein micelles and lactosylation decreased the availability of protein to plasmin. Whey-protein-free milk was the most plasmin resistant, followed by skim milk and lactose-free milk. Collectively, these results suggest that lactosylation plays a more significant role than whey protein association with the casein micelles in making protein resistant to plasmin activity. The plasmin-induced dissociation of the casein micelle was explored by identifying peptide release from the micelle. Upon plasmin-induced hydrolysis of the casein micelle, hydrophilic peptides, i.e. proteose peptones, were the first to dissociate from the casein micelle, followed by hydrophobic peptides, which had dissociation patterns that were identical to those of ?-casein. This suggests that the release of ?-casein from the micelle is too slow to cause gelation. Extensive plasmin-induced hydrolysis of the casein micelle leads to sedimentation in heat-treated milk because of the formation of ß-lactoglobulin–?-casein complexes and their aggregation with hydrolysed hydrophobic peptides. Overall, the results of the present study showed that casein modification can be useful in controlling plasmin activity and has developed our understanding of the plasmin-induced dissociation of casein micelles. Further research work is needed to understand the mechanism of plasmin’s selective hydrolysis pattern and the structural aspects of the substrate-binding pocket of plasmin. Studies on casein micelle dissociation separately and in conjunction with physicochemical changes during storage could be useful in further understanding the phenomenon of age gelation.

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  • Agriculture and rural development : the case of Fiji : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph.D.) in Economics, Massey University, Palmerston North, New Zealand

    Xing, Zhongwei (2015)

    Doctoral thesis
    Massey University

    Agricultural growth remains a key pillar for economic development in developing agriculture-based economies, however difficulties remained to integrate rural development, food value chains, technological and institutional innovations, environmental constraints that have changed in the context of agriculture’s role. The renewed attention on ‘new agriculture for development’ framework started to emerge to achieve several dimensions of development. This thesis empirically investigates the issues pertaining to new agriculture for development that can benefit economic growth and address the socio-economic dimensions of development in the case of Fiji. Utilising Fiji’s Household Income and Expenditure Survey 2008-09 dataset the study examines macro-micro-level role of agriculture that corresponds to new objectives and apply this approach to evaluate the agricultural efficiency-development linkages. The empirical methodologies apply appropriate time series, novel cross-sectional approaches, new agricultural indicators and its determinants that examines (1) the impact of agriculture and other sectors to enhance agriculture efficiency; (2) moving beyond farm income by assessing off-farm labour participation and supply allocation decisions in the agricultural households. To achieve desired dimensions of development beyond those driven by market competiveness, (3) the role of remittances in the agricultural production estimations provide a new direction and finding to increase income and identify the causes of success for scaling up agricultural output, followed by (4) reducing poverty and inequality in agricultural households. In addition to contributing to the broader debates about agriculture-economic development nexus, the findings are also the first on applying new agriculture for development framework in Fiji’s case. Results demonstrate that there exist sectoral linkages and to increase economic diversification developing forward linkages through innovations are crucial and advantageous for growth. Findings of double-hurdle factors indicate the push and pull factors that influence household heads’ decision to participate and allocate time in off-farm income-generating activities. This implies that demand for labour, even for low-wage workers will not increase without a dynamic rural economy. The failure of low-wage and subsistence living depends on availability of land tenure and investment in agro-based industry clusters. The effects of remittances on agricultural production and diversification show that remittances tend to encourage households to be more diversified in farming, and to grow more cash crops. Findings show that non-farm household income sources contribute significantly towards poverty reduction of the agricultural households. Policies aimed at low-wage to reduce income gaps and creating employment opportunities could exhibit higher labour productivity.

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  • Effects of ewe age on offspring development and performance : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Turitea, Palmerston North, New Zealand

    Pereira Loureiro, Maria Fernanda (2014)

    Doctoral thesis
    Massey University

    In New Zealand only approximately 30% of ewe-lambs are bred each year despite the advantages this practice can offer. Farmers have indicated a reason for not breeding ewe-lambs is that the offspring born to ewe-lambs are typically smaller and lighter to at least weaning. However, there is a lack of information on the post-weaning performance of ewe-lamb progeny in New Zealand. The objective of this thesis was to examine the effects of maternal age (ewe-lamb dams vs. adult ewe dams) on the performance of singleton and twin progeny and also the growth of their progeny to weaning. Progeny born to these two dam age classes were monitored to approximately 3.5 years of age. The results of this thesis have demonstrated that the growth and therefore live weight of offspring born to ewe-lamb dams was in general lower compared with those born to adult ewe dams, especially in twins. However, results also show that there is little impact of maternal age on offspring reproductive and lactational performance. Interestingly, there was a reversal of the influence on grand-offspring birthweight, whereby lambs with ewe-lamb granddams were actually heavier at birth. The lighter live weight of ewe-lamb progeny without negative effects on performance may even suggest these animals are more efficient; however, longer-term studies would be required to confirm this. In conclusion, these results indicate farmers can utilise progeny born to ewe-lamb dams without a negative impact on production, and in fact there may be a positive effect on production efficiency.

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