14,463 results for Doctoral

  • Investigations into the nutritional and sensory potential of taewa (Māori potatoes) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy, Nutritional Science, at Massey University, Palmerston North, New Zealand

    Wharemate, Zirsha R (2015)

    Doctoral thesis
    Massey University

    The term Taewa refers to a collection of at least 18 different potato cultivars belonging to the Solanum tuberosum family, which have been cultivated by the Maori peoples of New Zealand for at least 200 years. Due in part to its economic importance worldwide, the chemical and nutritional composition of today’s mainstream potato varieties, and the mechanisms by which composition impacts on their culinary and gastronomic properties, have been extensively researched. However few investigators have studied the nutritional, sensory or potential health properties of Taewa, or which Taewa varieties may be the most preferred for eating. Previous Taewa nutritional research has concentrated on anthocyanin, phenolic or flavonoid content and antioxidant potential, glycoalkaloid content and starch characteristics. The variation in culinary quality and different tuber pigmentation of Taewa suggest that the composition, nutritional and sensory properties of Taewa are diverse and are therefore worthy of investigation. The first goal of the PhD focused on identifying nutritionally beneficial or commercially viable properties of Maori potatoes. This was carried out by quantifying the macronutrient, selected micronutrient, phenolic and glycoalkaloid components and assessing antioxidant activity (using ORAC and FRAP analysis) of four Taewa varieties (Huakaroro, Karuparera, Moemoe, Tutaekuri) and comparing them against Nadine, a potato variety commonly available in New Zealand. Analysis was carried out on tuber flesh, tuber skin and whole tuber components over two consecutive harvests. In addition, the effects of 6 months storage at 4oC in 80-90% humidity and par-boiling on the nutrient content were also explored. The second goal of this research was to ascertain the most popular, commonly eaten and commonly grown Taewa varieties; preferred Taewa cooking and eating practices; the availability of Taewa cultivars across New Zealand and to collate information regarding marketable traits or factors that might affect Taewa consumption. In order to achieve this, group discussions were held with 25 adult participants between 18 to 75 years of age from the Manawatu region. Four key themes emerged from these discussions and were used to develop 20 questions for a larger scale survey from a wider crossection of Taewa consumers. The third goal of the research aimed to assess two characteristics of nutritional or health value (increased resistant starch in potato boiled then cooled at 4oC for 24 h) and antioxidant capacity (by measuring the total phenolic content, DPPH and FRAP potential) in four common Taewa varieties (Huakaroro, Karuparera, Moemoe, Tutaekuri) using a popular Taewa cooking practice (boiling whole with the skin on) to develop a Taewa product with improved health benefits. Consumer acceptance was then measured by assessing the sensory ratings of 56 adult volunteer subjects. Results of the nutrient analysis consistently showed all four Taewa had promising nutritional value with regards to a greater nutrient content, greater accumulation of resistant starch, greater total phenolic content and antioxidant capacity compared to Nadine. The nutrients in Taewa likely to be of most biologically significant nutritional value in comparison to Nadine and other more common NZ potato cultivars included the soluble and insoluble fibre content, the minerals potassium, magnesium and iron and the vitamins thiamine, pyridoxine and niacin. All four Taewa (particularly Tutaekuri) also showed excellent potential with regards to accumulating resistant starch and exhibiting antioxidant potential compared to Nadine. Commonly eaten Taewa varieties included Tutaekuri, Pawhero, Peruperu, Moemoe, Karuparera and Huakaroro. These Taewa varieties were also grown and eaten by residents in a greater number of regions across New Zealand than other Taewa varieties. Cooking and eating preferences included boiling them whole, unpeeled and cooked on their own; eating them hot or warm, with the skin on and seasoned with butter, salt and pepper. If destined to be pre-cooked or served cold, it was suggested that Taewa varieties should be waxy so as to hold together better, be purple or buttery-yellow to add interest with regards to visual appeal, be an appropriate size for the intended dish and have a sweet, nutty, buttery or delicate taste. New Zealanders should be encouraged to both eat and grow Taewa due to their value as a popular inexpensive food of high nutritional quality, their promise as a means through which to develop functional food products with added health benefits and their cultural significance to all New Zealanders as a unique heritage food. Government agencies, those involved in the Potato Industry, research institutions and funding agencies should be encouraged to work with Maori growers, to ensure the increased production and nationwide availability of Taewa and support the development of Taewa-based functional and snack food products in way that will be beneficial to all.

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  • Pacific Island Labour programmes in New Zealand : an aid to Pacific Island development? : a critical lens on the Recognised Seasonal Employer policy : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy, Massey University, Manawatu, New Zealand

    Rockell, Dennis Graham (2015)

    Doctoral thesis
    Massey University

    The New Zealand Recognised Employer (RSE) Policy was designed to remedy labour shortages in the horticulture/viticulture industry early in the twenty-first century. It was the first New Zealand contract labour migration programme to be designed with the explicit intent of the development of the source countries, consisting mainly of small Pacific Island States. This research sought to examine within a historical context whether the programme was beneficial to the source countries and communities, and whether the programme met the expectations of international labour conventions which New Zealand has signed. An attempt was made to discover whether, when compared with antecedent programmes in New Zealand and North America, the RSE represented a new paradigm in the design and implementation of a contract migrant labour programme. The field work was carried out for twenty months between December 2011 and August 2013, involved a grower survey and over 100 semi-structured interviews with Government officials, horticulturalists, migrant workers, pastoral care workers, and other interested parties. Time in southern Vanuatu was divided between interviewing migrant RSE workers in Port Vila and visiting 100 village communities on Tanna Island. Assessments were made of access to the programme for the rural and urban poor and of the positive and negative impacts of the programme. Positive features observed included the benefits of close government monitoring of worker accommodation, the transparency of the remuneration, the interest of many employers in assisting workers to remit funds to source communities, house building and infrastructural benefits gained by many workers, and the transfer of useful skills. Negative features included the powerlessness of the workers to negotiate their work conditions, the failure of some employers to address workers’ specific needs, the social dislocation of some workers leading to alcohol abuse, the frequency of work interruptions due particularly to weather conditions, the excessive work hours on some nightshifts at minimum wage, and a lack of connection between recruitment patterns and areas of greatest need. The RSE policy has come about in an era of migration optimism. Since the mid-1990s the total global flow of remittances has exceeded the level of official development assistance. However most literature regarding remittance flows and transnational communities is set within a context of diaspora. The RSE was carefully designed to prevent overstaying of visa entitlements, in order to prevent any growth of diaspora. Consequently the overall financial flows in the case of Vanuatu are small compared to such sectors as tourism, and the position of the RSE in the migration-development nexus is somewhat contradictory.

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  • Wastewater effects on epilithon, particularly sewage fungus, and water quality in the Manawatu River, New Zealand : a thesis presented in partial fulfilment of the requirements of the degree Doctor of Philosophy in Biotechnology at Massey University

    Quinn, John Martin (1985)

    Doctoral thesis
    Massey University

    Epilithon development, in relation to the discharge of domestic sewage, dairy factory and meatworks wastewaters, and its effects on water quality were studied in laboratory channels and in the Manawatu River. During the three year period of the study the organic material inputs to this river were progressively reduced to meet the requirements of water rights designed to limit the in-river BOD5 to 5 g.m-3 at the end of a defined mixing zone with the objective of maintaining adequate oxygen levels and controlling sewage fungus growth. Laboratory channel studies demonstrated that, for a given BOD5 addition, untreated dairy factory wastewater increased the heterotrophic growth 2-3 times more than primary treated meatworks wastewater. Similar observations were made in the Manawatu River. These varied growth responses could be accounted for by the different relative contributions of dissolved and low molecular weight (< 1000 daltons) organic compounds in the different wastewaters. The dissolved or low molecular weight (determined after sample ultrafiltration) BOD5 therefore provide more reliable general sewage fungus control parameters than BOD5. Current velocity and spates had marked influences on the development of benthic communities. Maximum sewage fungus biomasses on the natural bed were observed at current velocities of 0.2 to 0.45 m.s-1. Short heterotrophic fronds occurred at the maximum current velocity investigated of 1.16 m.s-1. Small spates of up to 50 to 70 m.s-3 caused preferential sloughing of heterotrophs over epilithic phototrophs which had developed on concrete plates at river flows of approximately 25 m3.s-1. Flows in excess of approximately 150 m3.s-1 removed growths of Cladophora glomerata which had developed at sites where the pre-spate current velocity was 0.3 to 0.4 m.s-1. Much higher flows, in excess of 400 m3.s-1, were required to remove the dense growths of the macrophyte Potamogeton crispus. Observations of sewage fungus biomass at various depths in the Manawatu River and growth rates on both upper, sunlight exposed, and lower, shaded, surfaces of concrete plates suspended in the water column indicated that solar radiation inhibition of heterotrophic growth is not important in the Manawatu River. These heterotrophic growths in the river were replaced by heavy phototroph-dominated epilithon as organic concentrations were reduced. Both communities had significant impacts on the suspended biomass and dissolved oxygen levels in the river. A computer model simulating summer low flow conditions in the Manawatu River predicted that the river can sustain average respiration rates of 20 and 24 g 02 m-3 d-1 at mean river temperatures of 21°C to 12°C respectively without breaching the statutory minimum permissable dissolved oxygen concentration of 5 g.m-3. A multiple regression model of the factors influencing epilithon respiration was developed from in situ chamber studies of a range of epilithic community types. This gave adequate predictions when tested against measurements over reaches below the discharges and predicted that the benthic biomass resulting in the maximum permissible respiration rates decreased from approximately 143 g AFDW m-2 at 12°C to 34 g AFDW m-2 at 21°C. A management strategy limiting the organic, but not the nutrient, inputs to the Manawatu River was shown to be unlikely to ensure consistent maintenance of the statutory minimum dissolved oxygen concentration. The implications for management of the river are discussed,

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  • Accounting in hospital organisations in New Zealand : a qualitative study in the reform context of 1984-1994 : a thesis presented for the degree of Ph.D. in Management Systems at Massey University

    Dixon, Keith (1994)

    Doctoral thesis
    Massey University

    Most general hospitals in New Zealand operate as part of the public sector. Since 1984, that sector has been the subject of radical, government led reforms. The espoused theory of these reforms has been expounded in terms of improving efficiency and effectiveness, and increasing accountability (Boston, Martin, Pallot & Walsh, 1991; G. Scott & Gorringe, 1989). The outward effects of these reforms on the hospital system consist of organisational changes, including the creation of hospital enterprises; changes to the way organisations are financed, including the use of taxes to purchase hospital products delineated according to diagnosis related groups [DRGs]; and changes to their management structures with a policy of general management replacing triumvirate management. Inevitably, these official changes have led to social changes to the system in general, and to the situated practice of accounting (Chua, 1988). In this study, an attempt has been made to describe and interpret these changes in the hospital system context, and to shed some light on the way in which accounting has come to be practised within that context. The theoretical posture of the study is a blend of rational, structuralist perspectives, and natural, interactionist ones (Boland & Pondy, 1983; Roberts & Scapens, 1985; Silverman, 1985; Denzin, 1989b). Consistent with this posture, the study strategy of control and design is a version of analytic induction (Denzin, 1989b; Silverman, 1985). The strategy comprised three phases during which a rough notion of accounting in hospital organisations was transformed into a working interpretation; data were gathered and analysed; and a thesis was compiled. The latter comprises thick descriptions and thick interpretations (Denzin, 1989a, 1989b; Patton, 1990) of the hospital system context and the situated practice of accounting; and a theory-in-use (Argyris, 1990; Argyris & Schon, 1974) which provides "explanations in terms of conditions of possibility" (Miller, 1990, p. 329) of what has been occurring in the hospital system, and the role of this situated practice in these occurrences. Underlying the study methodology was the notion of crafting both the study design and the theory which the study aimed to discover. The data were obtained using methods associated with naturalistic inquiry during time spent in the field. The use of these methods was prompted by a dearth of research published in this area relating to New Zealand, the wide range of perspectives among people participating or interested in the organisations, and the enormity of the changes to the system. The data were accumulated triangulately (Denzin, 1989b) from among different kinds of participants working on hospital sites (e.g., doctors, charge nurses, other health professionals and hospital staff with managerial responsibilities), from interested parties off-site (e.g, people working in the Department of Health, regional health authorities and organisations outside of the hospital system), and from official documents and published academic literature. The main vehicle used in the field was the nonschedule standardised interview (Denzin, 1989b), and inquiries focused, in turn, on practices relating to the budget, cost data reports and the annual report. In addition, interviews of a more general and exploratory nature, and some questionnaires, were used in the preliminary stages of the study. The picture which emerges from the study comprises four aspects: (a) a hospital system subjected to macro-level disturbances that have caused a mixture of effects in terms of structures, processes, interactions and outcomes; (b) an emergence of accounting since the mid-1980s in multiple roles, which are reflective and constitutive of organisational and social practices developing in the system (Ansari & Euske, 1987; Boland & Pondy, 1983; Burchell, Clubb & Hopwood, 1985; Chua, 1995; Kelly & Pratt, 1992; Loft, 1986; Roberts & Scapens, 1985); (c) qualified success for the situated accounting practice in the role of a political force in converting hospitals to a more effective form of organisation (Mintzberg, 1991); and (d) accounting practice at a fork in the road ahead, one way leading to its contamination of hospitals by inappropriate forces and forms (Mintzberg, 1991) based on production management; and the other leading to its emergence as an important support in a hospital system founded on a more conjoint organisational configuration (W. R. Scott, 1982) in which professionals and managers apply their craft cooperatively for the joint and several benefit of patients. These findings have implications which policy makers, health professionals and the public are urged to evaluate.

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  • Field and modelling studies of the effects of herbage allowance and maize grain feeding on animal performance in beef cattle finishing systems : a thesis in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Palmerston North, New Zealand

    Machado, Claudio Fabián (2004)

    Doctoral thesis
    Massey University

    The objetive [sic] of the work described in this thesis was to develop a mathematical model designed as a tool for research intended to improve the efficiency of finishing systems for 1-2 year old beef cattle under intensive grazing mangement [sic] on sown pastures in Argentina. The work involved a) three experiments in Argentina carried out to define the effects of herbage allowance and maize grain supplementation on herbage intake and animal performance, b) one experiment in Argentina following a preliminary study in New Zealand of seasonal variation in the composition and nutritive value of intensively managed beef pastures, and c) an exercise to develop a model of beef cattle production incorporating modules dealing with aspects of pasture production and utiisation [sic], herbage intake and animal performance. The results from the series of short-term grazing studies showed consistency in the comparison of the effects of increasing herbage allowance and supplementation on herbage intake and animal LWG (Chapter 4). A method combining the use of n-alkane and 13C method proved to be accurate for quantitative estimates of herbage and maize grain intake, and allowed estimates of a substantial variation in individual maize grain intake (between 31 to 41 % CV) when animals are supplemented in groups. The substitution rate (SR) measured in these studies varied little across experiments or level of grain at a herbage DM allowance of 2.5 % LW d-1 (0.36 and 0.38 kg herbage DM per kg grain DM for Chapters 3 and 4 respectively). Increasing level of herbage DM allowance increased quadratically the SR from 0.38 to 0.83 and 0.87 kg herbage DM per kg grain DM. The n-alkane method was effective in providing estimates of diet digestibility. Different methods for estimating diet composition, such as microhistological evaluation of faeces, differences in nutrient and component selection indexes and n-alkanes were used in the initial grazing trial (Chapter 2) but they were not considered to be reliable and they were too laborious for continued use under field conditions. The outcome of the studies on seasonal variation in herbage quality initially was useful in establishing a database of the range of values observed, and in demonstrating their relative robustness, at least under conditions of good pasture management. In these studies, herbage nutritive value did not seem to be a limiting factor for growing beef cattle, at least in terms of the minimum observed content of metabolisable energy (10.8 MJ ME kg DM) or crude protein (17.3 % DM). Additionally, significant relationships were established between morphological and maturity estimates and herbage nutritional variables in a pasture under grazing conditions. These relationships showed promise for future use in the prediction of herbage nutritive value, but require further work. The model developed ("BeefSim"), represents the main biological dynamic processes of the target system of this thesis, together with additional management decision and financial estimates. It was shown that the model presents adequate flexibility and can be interrogated in terms of its response to different management conditions, scenarios and timeframes. Pasture management and grain feeding were controlled in an interactive management module responding to deviations in pasture conditions and animal liveweight from pre-determined targets. Two key outcomes of the model, liveweight gain and herbage intake were accurately predicted when compared against experimental information under different levels of herbage allowance and maize feeding. System comparisons developed with the model showed agreement with the literature, and maize grain feeding associated with the monitoring procedure demonstrated an effective use of grain in the system. The model provides a good biological basis for a holistic appraisal of the effects of "process technologies" such as grain feeding in beef cattle finishing systems, and will be developed further.

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  • Development of an autonomous kiwifruit harvester : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Industrial Automation at Massey University, Manawatu, New Zealand.

    Scarfe, Alistair John (2012)

    Doctoral thesis
    Massey University

    The already intensive labour requirements within the New Zealand kiwifruit industry are increasing. Furthermore, ZESPRI Group Limited is targeting a threefold increase in industry return by 2025 (from approximately $NZ1Billion to $NZ3Billion). Development of autonomous mechanised solutions to assist manual labour is emerging as a strategic necessity. The objective of this research was to develop a commercially viable autonomous kiwifruit harvester (AKH). The AKH must be capable of operating within variable and complex on-orchard environments to minimise manual labour requirements. Successful completion required development and integration of autonomous: 1. Fruit identification and localisation 2. Custom robotic arms with soft fruit extraction harvesting hands 3. Custom robotic arm for soft fruit handling 4. Transportation platform with navigational sensing and strategies 5. Storage bin collection and drop-off The AKH has four robotic harvesting arms with hands specifically designed to mimic the human fruit harvesting action. Remotely mounted stereoscopic vision identifies and localises fruit. The fruit locations are mapped into the harvesting arms’ coordinate space allowing fruit extraction. The presented system configuration resolves the slow harvest rates experienced by other systems. Practical on-orchard testing identified additional environmental complexities that present the greatest challenge to consistent fruit identification. These are mainly from natural lighting effects. Stereoscopic machine vision (SMV) was investigated as the primary navigation sensor. However, diverse environmental conditions (lighting and structure appearance) made consistent object detection unreliable. Consequently, a light detection and ranging/SMV combination was used to achieve reliable navigational object detection and fruit storage bin identification. Practical on-orchard testing and analysis verified AKH operational ability (testing was limited due to a vine killing bacterial (Psa-V) outbreak restricting orchard access): 1. Fruit identification (83.6% of crop) with combined localisation and extraction accuracy of 3.6mm in three-dimensional space 2. More gentle fruit harvesting and handling than humans harvesting 3. Reliable object detection and path planning for navigation. Over the twenty metre scanning range 96% of the in-row objects were correctly classified to reliably determine the drive path 4. Reliable fruit storage bin identification and localisation (98% correct classification) 5. Commercially viable manufacture cost less than $130,000 per unit 6. Although full commercial operation was not achieved, modifications are identified to rectify the limitations Key system improvements are presented for: 1. High intensity artificial lighting for increased fruit identification rates. Natural sunlight variations affected identification ability, minimising this affect will increase identification rates 2. Alter the storage bin filling arm geometry to permit complete storage bin filling 3. Sensing the robotic arms’ position to resolve positioning errors Furthermore, ZESPRI Group Limited is targeting a threefold increase in industry return by 2025 (from approximately $NZ1Billion to $NZ3Billion). Development of autonomous mechanised solutions to assist manual labour is emerging as a strategic necessity. The objective of this research was to develop a commercially viable autonomous kiwifruit harvester (AKH). The AKH must be capable of operating within variable and complex on-orchard environments to minimise manual labour requirements. Successful completion required development and integration of autonomous: 1. Fruit identification and localisation 2. Custom robotic arms with soft fruit extraction harvesting hands 3. Custom robotic arm for soft fruit handling 4. Transportation platform with navigational sensing and strategies 5. Storage bin collection and drop-off The AKH has four robotic harvesting arms with hands specifically designed to mimic the human fruit harvesting action. Remotely mounted stereoscopic vision identifies and localises fruit. The fruit locations are mapped into the harvesting arms’ coordinate space allowing fruit extraction. The presented system configuration resolves the slow harvest rates experienced by other systems. Practical on-orchard testing identified additional environmental complexities that present the greatest challenge to consistent fruit identification. These are mainly from natural lighting effects. Stereoscopic machine vision (SMV) was investigated as the primary navigation sensor. However, diverse environmental conditions (lighting and structure appearance) made consistent object detection unreliable. Consequently, a light detection and ranging/SMV combination was used to achieve reliable navigational object detection and fruit storage bin identification. Practical on-orchard testing and analysis verified AKH operational ability (testing was limited due to a vine killing bacterial (Psa-V) outbreak restricting orchard access): 1. Fruit identification (83.6% of crop) with combined localisation and extraction accuracy of 3.6mm in three-dimensional space 2. More gentle fruit harvesting and handling than humans harvesting 3. Reliable object detection and path planning for navigation. Over the twenty metre scanning range 96% of the in-row objects were correctly classified to reliably determine the drive path 4. Reliable fruit storage bin identification and localisation (98% correct classification) 5. Commercially viable manufacture cost less than $130,000 per unit 6. Although full commercial operation was not achieved, modifications are identified to rectify the limitations Key system improvements are presented for: 1. High intensity artificial lighting for increased fruit identification rates. Natural sunlight variations affected identification ability, minimising this affect will increase identification rates 2. Alter the storage bin filling arm geometry to permit complete storage bin filling 3. Sensing the robotic arms’ position to resolve positioning errors

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  • Behaviour of fat globules and membrane proteins under different processing environments as related to milk powder manufacture : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology

    Ye, Aiqian (2003)

    Doctoral thesis
    Massey University

    The objective of the first part in this study was to gain a better understanding of the protein components of the milk fat globule membrane (MFGM). In the second part, the influence of processing factors on the fat globules and the MFGM during the manufacture of whole milk powder were examined. Relationships between the state of the MFGM in whole milk powders and their reconstitutions properties were also explored. The MFGM proteins, isolated from early-, mid- and late-season fresh whole milks, were characterized using one- and two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing and non-reducing conditions. SDS-PAGE under reducing conditions showed the presence of about 40 protein bands, ranging in molecular weight from 15 to 200 kDa. The major MFGM proteins e.g., xanthan oxidase, butyrophilin, PAS 6 and PAS 7 constituted 60-70% of total MFGM proteins while 20-30% were minor proteins. Two-dimensional SDS-PAGE indicated that xanthine oxidase and butyrophilin might be complexed via intermolecular disulfide bonds in the natural MFGM. The examination of MFGM proteins heated at > 60 °C in the absence of skim milk proteins (caseins and whey proteins) showed that xanthine oxidase and butyrophilin interacted further to form very high molecular weight protein complexes, whereas PAS 6 and PAS 7 were relatively heat stable and did not form complexes. Heat treatment of fresh whole milk in the temperature range 65-95 °C caused incorporation of β-lactoglobulin (β-1g) into the MFGM. Small amounts of α- lactalbumin (α-la) and κ-casein were also observed in the MFGM material of heated milk. The amounts of β-lg and α-la that associated with the MFGM increased with an increase in temperature up to 80 °C, and then remained almost constant. The maximum values for β-lg and α-la association with the MFGM were ~1.0 mg/g fat and ~0.2 mg/g fat, respectively. Association of β-lg and α-la with the MFGM was described by a first-order reaction (65-85 °C for β-lg and 70-80 °C for α-la) in the low temperature range and by a second-order reaction in the high temperature range (85-95 °C for β-lg and 80-95 °C for α-la). Arrhenius plots showed an abrupt change in temperature dependence of the rate constants at 85 °C for β-lg and 80 °C for α-la. Of the major original MFGM proteins, xanthine oxidase and butyrophilin were not affected by the heat treatment of whole milk, whereas PAS 6 and PAS 7 decreased during heating. Interestingly, this behaviour is in contrast to that shown by these proteins in systems containing no skim milk proteins. The changes in fat globule size and MFGM proteins during the manufacture of whole milk powder were determined using light scattering, SDS-PAGE, confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Heat treatment of whole milk by direct stream injection (DSI) prior to evaporation caused a decrease in the fat globule size and an increase in the MFGM protein, through the association of caseins and whey proteins with the MFGM material. Evaporation of milk by a multiple-effect falling film evaporator caused a gradual decrease in the fat globule size and an increase in the MFGM protein after each effect. Caseins dominated the total MFGM protein, indicating the adsorption of casein micelles to the newly formed surface of the fat globules during evaporation. When whole milk was preheated (95 °C for 20 s) before evaporation, the amounts of total MFGM protein were higher (~6 mg/m2 compared to ~4 mg/m2 for the non-preheated whole milk) because of association of whey proteins with the native MFGM proteins and casein micelles. The average fat globule size decreased further upon homogenisation of the concentrated milk. The amount of MFGM protein (mg/m2) of concentrated milk also increased after homogenisation, the extent of the increase being dependent upon the temperature and pressure of homogenisation. Furthermore, heat treatment of concentrated milk to 79 °C either before or after homogenisation also increased the amount of MFGM protein. However, at the same homogenisation temperature and pressure, the amounts of whey proteins in the MFGM of the concentrated milk that was heated after homogenisation were higher than the concentrated milk that was heated followed by homogenisation. The amounts of the major native MFGM proteins did not change during homogenisation, indicating that the skim milk proteins did not displace the native MFGM proteins but adsorbed onto the newly formed surface. The fat globule size of homogenized concentrated milk decreased after spray drying, while the amount of MFGM protein (mg/m2) decreased slightly. Some "uncovered fat" was observed on the surface of powder particles. It is possible that the proteins do not adsorb to all newly formed fat surfaces during spray drying. The reconstitution properties of whole milk powders produced using different processing treatments were determined. High homogenization pressure and temperature used before spray drying resulted in poor reconstitution properties of the powder, particularly when the heat treatment was carried out after homogenization. It is suggested that the proteins adsorbed at the fat globule surfaces during homogenisation of the concentrated milk and their subsequent aggregation during heat treatment play a key role in determining the reconstitution properties of whole milk powders.

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  • e-Learning systems success in an organisational context : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Management Information Systems at Massey University, Palmerston North, New Zealand

    Samarasinghe, Samantha Malkanthi (2012)

    Doctoral thesis
    Massey University

    Issues around effective implementation, management, and success of e-Learning systems have drawn the attention of many researchers. However, e-Learning systems success research still lacks models and frameworks addressing organisational dimensions along with instructor and learner dimensions, particularly in the New Zealand higher education context. Hence, the purpose of this research was to explore the dimensions of e-Learning systems success in an organisational context. Based on a broad review of literature, I formulated a multidimensional framework of e-Learning systems success in the organisational context and used the framework to develop two e-Learning success models: a model from the instructor perspective and a model from the learner perspective. To test the framework and to explore the dimensions of e-Learning systems success, I conducted three empirical studies. First, a preliminary study with 43 e-Learning experts was carried out to confirm the content validity of the measurement instruments. The e-Learning systems success models were then tested in the organisational context of New Zealand universities by fitting the instructor model to data collected from 204 instructors engaged in e-Learning and by fitting the learner model to data collected from 189 students with e-Learning experience. The study identified quality of the e-Learning development and implementation process as a dimension of e-Learning systems success. This study was the first to formulate and to test a measure for e-Learning development and implementation process quality. An insight into the instructor views of this dimension was obtained by qualitative analysis of their free-text comments. Moreover, the study was the first to formulate and to test a multidimensional e-Learning systems success model based on DeLone and McLean’s (2003) IS success model focusing on instructors as the stakeholders. The study investigated the effect of organisational dimensions on other dimensions of e-Learning systems success, accounting for both instructor and learner perspectives in the same organisational context. Of the organisational dimensions considered, quality of the e-Learning system was the most influential. Quality of the e-Learning development and implementation directly affected other organizational dimensions, system quality and institutional support to the instructors, and affected instructor dimensions indirectly.

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  • The aspirin augmented standardized lactulose mannitol test as a measure of the 'health' of the gastrointestinal tract : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Massey University, Palmerston North, New Zealand

    Sequeira, Ivana Roosevelt (2015)

    Doctoral thesis
    Massey University

    Content removed from digital version of thesis due to copyright reasons: Sequeira, I. R., Lentle, R. G., Kruger, M. C., & Hurst, R. D. (2015). Ascorbic acid may exacerbate aspirin-induced increase in intestinal permeability. Basic and Clinical Pharmacology and Toxicology, 117(3), 195-203.

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  • Anomalous children : orphans and interlineage marriages in Malawi : 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

    Donovan, Elaine (2015)

    Doctoral thesis
    Massey University

    Although lineage studies have largely been forgotten by contemporary anthropology, tracing descent through either the maternal or paternal line remains a meaningful feature of everyday relatedness for people in Malawi. Following Harré’s discursive approach, this thesis reconceptualises matriliny and patriliny as clusters of relatedness practices avoiding a tendency to reify lineages as social structures, ascribing them erroneously with agency. This ethnographic study explores what it is to be an orphan in Malawi today and why orphans of interlineage marriages, that is, marriages between patrilineal women and matrilineal men, seem to be rendered the most vulnerable to mistreatment. The term orphanhood suggests a fixed state, defined by the death(s) of parent(s), from which children cannot escape until they reach adulthood. However, I found that in Malawi, being an orphan is more of a process, as people can be positioned as no longer an orphan when their living conditions improve. Being an orphan in Malawi is to be in need both materially and emotionally, having lost family support through death, illness or abandonment. It is a position often characterised by feelings of loneliness and isolation due being excluded from family sharing practices. Orphans of interlineage marriages seem to be the most vulnerable, due to falling between two contrasting discursive constructions of children's belongingness. In matrilineal groups, children belong to their mother’s family. Conversely, in patrilineal communities, children are affiliated to their father’s family providing the bridewealth requirements have been fulfilled. Thus, children of interlineage marriages are anomalously positioned as belonging nowhere. Matters become more complex if the matrilineal family pay the patrilineal custom of bridewealth as they (mis)interpret it as providing indisputable rights to the children. This (mis)interpretation originates from the colonial period when bridewealth became an official and enforceable means of determining to whom children belonged, particularly in cases of interlineage marriages. Thus, matrilineal families claim the children based on a (mis)perceived transaction-based entitlement, only to then mistreat them. They claim the children belong to them not as kin, characterised by bi-directional belonging (belonging to each other) but in terms of unidirectional (transactional) belonging, as in property.

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  • The role of substrate hydrogeology and surface hydrology in the construction of phreatomagmatic volcanoes on an active monogenetic field (Auckland, New Zealand) : a thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth Science at Massey University, Palmerston North, New Zealand

    Agustín Flores, Javier (2015)

    Doctoral thesis
    Massey University

    Material removed due to copyright reasons (appendices B, D and E): Agustín-Flores, J., Németh K., Cronin, S., Lindsay, J., Kereszturi, G., Brand, B., & Smith, I.E.M. (2014). Phreatomagmatic eruptions through unconsolidated coastal plain sequences, Maungataketake, Auckland Volcanic Field (New Zealand). Journalof Volcanology and Geothermal Research, 180, 203-224. doi.org/10.1016/j.jvolgeores.2014.02.021 Agustín-Flores, J., Németh, K., Cronin, S., Lindsay, J., & Kereszturi, G. (2015). Shallow-seated explosions in the construction of the Motukorea tuff ring (Auckland, New Zealand): Evidence from lithic and sedimentary characteristics. Journal of Volcanology and Geothermal Research, 304, 272-286. doi.org/10.1016/j.jvolgeores.2015.09.013 Agustín-Flores, J., Németh, K., Cronin, S., Lindsay, J., & Kereszturi, G., 2015. Construction of the North Head (Maungauika) tuff cone: a product of Surtseyan volcanism, rare in the Auckland Volcanic Field, New Zealand. Bulletin of Volcanology, 77, 11. doi:10.1007/s00445-014-0892-9

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  • "Help yourself to CBT" : mechanisms of change within a group guided self-help programme targeting low mood in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology, Massey University, Albany, New Zealand

    Forman, Inga (2015)

    Doctoral thesis
    Massey University

    This thesis explores the processes of change within a Low Intensity Cognitive Behaviour Therapy (LICBT) intervention targeting low mood in a community sample of adults in New Zealand. Low intensity interventions (e.g. self-help programmes) are a relatively new area of interest in the area of psychological treatment. They aim to increase people’s access to evidence based methods of therapy whilst removing many of the major issues associated with traditional treatment methods, such as long waiting lists, financial limitations, and inaccessibility to many in the wider community (Lovell & Richards, 2000). LICBT interventions have been shown to significantly improve outcomes for mild to moderate depressive symptoms across different samples (McKendree-Smith, Floyd & Scogin, 2003). The current study assessed change processes within the guided self-help programme ‘Living life to the Full’ (LLTTF, Williams, 2008). Due to methodological issues, the study was not able to soundly address hypotheses regarding the effectiveness of the programme. However, the statistical significance of changes across outcome measures were examined along with their clinical significance at an individual level. Participants showed statistically significant reductions in psychological distress from baseline to post-programme. Results for depression and quality of life were not significant. When results were examined at a single case level for clinical significance, a number of participants showed clinically significant change across the three main outcome measures. An analysis of individual change processes was also completed, with the examination of early rapid response patterns for individual participants. Early rapid response patterns occurred for a number of participants, supporting preliminary evidence that certain change patterns apparent in CBT research may also occur in LICBT interventions. A link was also found between early rapid responding and more positive post programme outcomes. Group process results showed that as predicted, the low intensity nature of the programme is likely to have affected the perceived group environment and relationship to the group facilitator. The LLTTF programme was positively evaluated by the majority of programme completers and though the sample size was small, results suggest this type of intervention is an effective platform from which to further develop low intensity therapeutic paradigms in New Zealand.

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  • 'Tu ga na inima ka luvu na waqa' : (The bail to get water out of the boat is in the boat yet the boat sinks) : the cultural constructs of health and wellbeing amongst Marama iTaukei in a Fijian village in Lau and in a transnational Fijian community in Whanganui, Aotearoa : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Social Policy at Massey University, Palmerston North, Aotearoa

    Meo-Sewabu, Litea Diloki (2015)

    Doctoral thesis
    Massey University

    The study identified that there are a number of criteria that have to be met in order for Marama iTaukei or Indigenous Fijian woman to be perceived as healthy. Findings suggest that current health frameworks need to take into account the determinants of health that are informed by cultural constructs that emerged as key findings in this study including: Dau veiqaravi or being of service, Taucoko ni qaravi itavi or completion and completeness of tasks, Na veiwekani or maintaining harmony in relationships and Kena I rairai outward reflection or physical appearance and Bula vakayalo or Sprituality. Exploring the intricate and delicate weaving of Fijian epistemologies and Western philosophies as illustrated through the Tanoa Health Belief Framework emerging from the findings in this thesis, may ideally be the future to improving health and wellbeing for, Marama iTaukei. The Tanoa Health Belief Framework has been developed to assist health and community workers to assess the determinants of health and wellbeing amongst Fijian women. This was a qualitative study with a total of 23 participants conducted in two geographical locations, one in Fiji and one in Aotearoa. The study was not a comparative study however; the study in Fiji enabled an exploration of how perceptions and experiences of health and wellbeing have evolved as Fijian women have migrated to Aotearoa. Ethnography was used as the overarching methodology as well as the Vanua methodology. Methods used included talanoa, participant observation and photovoice. In terms of methodology, a Tali magimagi Framework pulled together the strands of what constitutes this thesis. This includes the process of ‘cultural discernment’ emerging from the ethics process encountered in this research. The concept of ‘culturally embedded agency’ is also presented in this thesis arguing that there needs to be an agency-oriented approach to women’s agenda. Culturally embedded agency calls for social policy that incorporates full participation of women in society, inclusive of indigeneity goals, cultural wellbeing and fairness. Implications of this study and recommendations are based on ensuring that health and wellbeing is achieved for the Marama iTaukei.

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  • Satisfaction with life and social comparison among older people : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Health Science at Massey University, Manawatu, New Zealand

    Rodgers, Vivien Kaye (2015)

    Doctoral thesis
    Massey University

    Introduction: In a rapidly greying world, successful ageing is an important concept and goal. While this remains poorly-defined in the literature, there is wide agreement that satisfaction with life is a major contributor, together with health and functional ability. It has been suggested that the perception of satisfaction with life might be affected by social comparison, but little is known about this relationship, particularly among older people. Consequently, this study investigates the impact of health-related and social comparison variables on the perception of satisfaction with life at various stages of old age. Methods: A cross-sectional survey of 542 community-dwelling people aged 65+ was conducted to measure health (physical and mental), functional ability, satisfaction with life and social comparison dimensions. Participants were randomly selected from the general electoral role of the Manawatu region of New Zealand. The Short Form-12 Health Survey measured perceived physical and mental health, the Groningen Activity Restriction Scale measured functional ability, the Satisfaction With Life Scale measured life satisfaction and the Iowa-Netherlands Comparison Orientation Measure assessed social comparison. Additional demographic information was collected. Age groups (65-74, 75-84, 85+) were compared. Results: A marked difference was found in satisfaction with life before and after age 85 years, that was not explained by health (physical or mental), functional ability, demographic factors or comparison frequency. The oldest participants (aged 85+) consistently reported the highest levels of satisfaction with life. This same group reported predominantly making downward social comparisons (with those doing worse). Conclusions: Important links were found between satisfaction with life and downward social comparison. Better understanding of comparison drivers across older age will progress the discussion on what impacts the perceptions of satisfaction with life and contributes to successful ageing.

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  • Kia Tiori ngā Pīpī : mā te aha e kōrero Māori ai ngā taitamariki ngā wharekura o Te Aho Matua? : he turinga roa hei whakatutuki i ngā tikanga o Te Tohu Kairanga i Te Kunenga ki Pūrehuroa, Papaioea, Aotearoa

    Poutū, Hinurewa (2015)

    Doctoral thesis
    Massey University

    I ara ake te kohanga reo, nawai ra, ko te kura kaupapa Maori me te wharekura, i te mura o te ahi, i ta te iwi Maori pakanga ki te whakaora i tona reo. Heoi, ka pahemo tona toru tekau tau, a, e ai ki nga tatauranga o na tata nei kei te taheke tonu te taupori o te arero matatau ki te reo Maori. Na reira, kaore ano te puehu kia tau, kei te kakari tonu kia haumanutia ake te reo taketake o Aotearoa. Ka mutu, kua tupu mai he reanga taiohi i nga wharekura, me te aha, he toa taitamariki kei te aro a-kapa hei hapai, hei wawao i te reo kia ora tonu ai apopo. Ko nga whanonga reo me nga waiaro o taua hunga te matapihi ki te oranga o te reo a nga tau e tu mai nei, heoi kaore ano nga pitopito korero mo te reanga taiohi kia aroa nuitia i roto i nga rangahau mo te reo Maori. Tera ia te tuatau, ma te korero i te reo ka ora taua reo. Na kona i toko ake te patai, ma te aha e korero Maori ai nga taitamariki o nga wharekura o Te Aho Matua? He aha nga whakaawenga e korero Maori ai taua whakatupuranga? Otira, ki a wai, ki hea, hei ahea ratou korero Maori ai? He mea kawe tenei rangahau i raro i nga tikanga Maori, i Te Aho Matua o nga Kura Kaupapa Maori me ta te Maori kaupapa rangahau. I whaia te rangahau tatauranga hei kohikohi i nga raraunga mo te whanuitanga o te kaupapa, a, ka uiuia nga tangata kia rangona te hohonutanga o nga pitopito korero. E 478 katoa te hunga i whakautu i te rarangi patai i te ipurangi, otira he akonga o naianei, o mua hoki, no nga wharekura puta noa i Aotearoa. He mea uiui nga pukorero e 51 o nga wharekura e whitu o te rohe o Te Upoko-o-Te-Ika. Ko ratou ma nga taitamariki kei te wharekura tonu e ako ana, ko era kua wehe, kua puta ki te ao whanui, tae atu ki etehi o nga matua me nga pouako. Na, ehara i te mea he mama tenei mea te tupu mai i te taiao reo Maori. Kua riro ma te matatahi e waha nga tumanako o nga matua ki te oranga o te reo. Otira, he matatini te tuakiri o te taiohi reo Maori, e noho nei i te ao hurihuri, e patukituki ana, e taukumekume, e whiwhiwhi ana. Ara nga moreareatanga, nga akinga me nga whakawai o te aropa, o reo ke, o tikanga ke, o hangarau ke hoki. Ko te whanau, ko te kura, ko te tuakiri ake o te taiohi wharekura, tae atu ki nga whakaawenga o te ao whanui e whakaaweawe mai ana i te korero Maori a tenei reanga.

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  • Hierarchical Bayesian modeling of criterion variance in probabilistic categorisation as an analogue to signal detection : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Manawatū, New Zealand

    Taylor, Robert T (2015)

    Doctoral thesis
    Massey University

    Variance in the decision criterion across trials induces response inconsistencies which in turn result in suboptimal performance. Criterion variability is largely thought to be driven by internal mechanisms; however, factors external to the observer may also affect response consistency. Specifically, how trial-by-trial feedback is delivered can influence the stability of the criterion across trials. This thesis examined how two types of feedback (stochastic and deterministic) influenced performance in probabilistic categorization tasks, which served as analogues to the orthodox detection task. Critically, feedback that is related to the statistical properties of the stimulus distributions (i.e., feedback for which event had occurred) results in lowered performance when compared to feedback that is provided deterministically (i.e., relative to the optimal cut-off). This result held more consistently in conditions where there was greater (probabilistic) confusability among the stimuli. The effects upon the criterion were also examined by comparing dynamic signal detection models that allowed for trial-by-trial criterion shifts. Hierarchical Bayesian modeling was implemented to fit the dynamic criterion models, allowing for model comparisons to proceed using Bayes Factors. It was found that simple errorcorrecting models predicted the data less well than models that included shifts after correct decisions. However, criterion shifts after correct decisions can be better described by a weighted moving average criterion which shifts toward the current stimulus, rather than away. This finding arose through the explicit modeling of the stimulus magnitudes on each trial. Finally, a model was contrived that both allowed stimulus magnitudes to influence criterion shifts and make the effects of feedback more overt. The model suggests that the way feedback information is stored over trials drives shifts in the criterion, and that feedback will influence how storage is facilitated. However, the model could not completely describe the effects of feedback nor fit the empirical data as well as already established dynamic criterion models.

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  • Racism in Aotearoa New Zealand : analysing the talk of Māori and their Pākehā partners : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand

    Pack, Sylvia (2016)

    Doctoral thesis
    Massey University

    Previous studies on racism in the field of critical social psychology have focused on perpetrator talk and text, perpetrator personality and cognition, and in-group psychology. Research examining targets' perspectives and responses to racism and race theory is rare. The current study redresses a little of this imbalance by exploring the accounts of indigenous Maori of Aotearoa New Zealand and their partners. The researcher, a Pakeha (B.A. Maori Studies), used long standing Maori contacts to establish trust, and also sought approval from a Maori Cultural advisor, the Massey University Human Ethics Committee, and a local marae (Takapuwahia) before beginning the project. Interviews were conducted with 24 participants aged 30-74, 19 of whom were Maori (10 women, 9 men) and five of whom were Pakeha women partners. Participants were asked three open ended questions. Had they had experiences of racism, and if so, could they describe them? Why did they think the racism occurred? Was there a solution? The epistemology chosen to underpin the analyses was social constructionism, which allowed the inclusion of political and social contexts and power issues, and also acknowledged the power of language to not merely reflect reality, but actively construct it. A data driven inductive approach was employed to bring to light the uniqueness of the participants' perceptions. Thematic analysis (Braun & Clarke, 2006) informed by social constructionism, was used in the first paper Resisting racism, to outline three themes: difficulties in expressing resistance due to power imbalance or stereotyping, non-vocalised resistance, and vocalised resistance, which was the most stressful and successful response. In Accounting for racism, a micro-level analysis of participants' talk draws on the discourse analytic tradition of Potter and Wetherell (1987) to highlight four main discourses: Ignorance of racism and Maori people, media promotion of negative stereotypes, an innate Pakeha sense of superiority, and institutionalised racism. Thematic analysis is used again in Reducing racism to define four main themes: Structural racism with attention to the workplace and the justice system, education's role in anti-racism practices, increased interaction, and becoming inclusively 'Kiwi' while practising mutual respect. This respect contributes key insights from the targets' persective, and addresses a gap in current research which is focussed almost exclusively on perpetrator theory. In addition, this study holds significance for psychologists, educationalists, researchers and policy makers as it brings fresh understanding on racism against Maori and how to best reduce it in Aotearoa, New Zealand.

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  • An evaluation of traditional staff development practices for implementing change in university teaching : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Education, Faculty of Education,

    Ashcroft, Eric Robert (1987)

    Doctoral thesis
    Massey University

    This study examined the effectiveness of different staff development practices in implementing change in tertiary teaching. It assessed the effects of participation in three modes of staff development on staff attitudes, knowledge and teaching behaviours relevant to the teaching role. In particular, the research investigated effects of traditional and alternative modes of staff development operating in a New Zealand university for the five year period from 1979 to 1983. A new four variable model of implementation composed of interdependent influencing factors, the learning process, system components and an innovation, was used. Specified change in an instructional role was defined as the criteria of success. Changes were grouped within the three interrelated categories of attitudes, knowledge and behaviour. This research indicates the efficacy of Inner-directed methods for implementing change in attitudes. Even marked changes in attitudes however were not accompanied by changes to knowledge or instructional behaviour. For acquisition of new knowledge and implementation of new behaviours it is proposed that specific training, based on individually relevant goals, effects and involvements is necessary. Finally it is proposed that consistent application of the principles of learning is necessary for implementation of innovations in the instructional role of academic staff.

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  • Career assistant/deputy principals : asleep at the wheel or motivated drivers in education? : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Education, Institute of Education, Massey University

    Shore, Kevin (2015)

    Doctoral thesis
    Massey University

    This study focuses on a largely unrecognised group of secondary school assistant/deputy principals who have no desire to pursue principalship. Findings from the study have shown that these assistant/deputy principals who, for the purpose of this study are called ‘career AP/DPs’, play a significant role in the leadership of New Zealand secondary schools yet there is little research focused on the assistant/deputy principalship as a vocation. Consequently, the intentions of this study are to develop a more complete understanding of this group in order to ensure that career AP/DPs are a recognised group of educational leaders with a distinct mission to support principals in leading our New Zealand secondary schools. The research design employed a mixed methods approach. It used a survey questionnaire to identify those AP/DPs who identify as career AP/DPs and then focus group interviews with selected groups of career AP/DPs to develop a more complete understanding of the group. The findings from the study highlight that career AP/DPs have followed a serendipitous career journey where key colleagues have been crucial in championing their leadership aspirations. Career AP/DPs gain satisfaction from the daily contact that they have with students, caregivers and staff and enjoy the psychological rewards that come from making a difference in their schools. However, they are clearly disappointed that they are not able to make a wider contribution to teaching and learning in their schools and advocate for a more significant role in this portfolio. Career AP/DPs are strongly attached to their leadership teams including the principal and acknowledge them as the most significant professional support they have providing the conditions for them to grow and fully enjoy the psychological rewards that come from serving in this position.

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  • Evolution of diversity : analysis of species and speciation in Hemiandrus ground wētā : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology, Massey University, New Zealand. EMBARGOED until 1 November 2017

    Smith, Briar Leigh Taylor (2015)

    Doctoral thesis
    Massey University

    Patterns of biodiversity and endemism in New Zealand are explored, with a focus on the ground weta genus Hemiandrus. I first investigated factors that determined regional levels of endemism using a generalised linear model based on analysis of 2322 species of endemic New Zealand invertebrates. I found that widespread species are uncommon in New Zealand and most invertebrates occupied few regions. Number of endemic species per region was positively correlated with total number of species and size of the region 3 million years ago. Within one clade of Hemiandrus I found that North and South Islands differed in how they were occupied: South Island had many species with small non-overlapping ranges, whereas North Island was largely dominated by a single species. This is likely due to differences in age of different parts of New Zealand, yet this pattern was absent in another clade of ground weta species, showing that properties of species themselves also have a large impact on species ranges and speciation. I applied several strategies to the Hemiandrus maculifrons species complex to test putative species boundaries (chapter 3). I compared morphological methods (Gaps in Continuous Characters across Geography (GCCG)) and genetic methods (Bayesian Species Delimitation, Rosenberg's P(AB), P(Randomly Distinct), P ID(Liberal)). Some of these strategies indicated that all or nearly all mtDNA clades tested represented separate species, while others indicated that no clades were likely to be distinct species. I concluded that H. maculifrons comprises three species (plus an under-sampled microendemic species, chapter 4); a conclusion that is discordant with the results of the “species delimitation” methods but consistent with other genetic, morphological and distributional data. Since the genus Hemiandrus was thought to comprise only nine named species but dozens of alleged species, I tested whether the purported diversity accurately reflected biological diversity in the genus or whether it was exaggerated due to speculative classification (chapter 5). To do this, I applied traditional techniques to search for qualitative or quantitative differences between individuals using a model where species are separately evolving lineages that form separate genotypic clusters with no or few intermediates when in contact (Mallet 1995). Most proposed operational taxonomic units were supported, but some names appear to be synonymies while others appear to encompass more diversity than previously recognised. I concluded that Hemiandrus comprises at least 25 species, but as specimens representing all tag-names1 1 A tag-name is an informal name that indicates an entity that may be a separate species, monophyletic group or separate interbreeding population of uncertain taxonomic rank (Leschen et al. 2009). were not available, additional diversity may exist within Hemiandrus than recognised here. Phylogenetic analysis of mtDNA sequences identified two major clades within New Zealand Hemiandrus. Using nuclear markers and morphological traits I found strong support for these two clades. Derived shared traits were identified that can determine to which clade each species belongs. Concordance between genetic markers (four loci) and morphology resolved evolutionary relationships from which I propose dividing the group into two separate genera.

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