Higher Degree Theses

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“We don’t have to carry the shame”: Autobiographical documentary filmmaking as a collective healing artifact for child abuse survivors
(The University of Waikato, 2026) Visage, Anthea; Perrott, Lisa; Schott, Gareth R.
Sitting at the intersection between autobiographical documentary theory and child abuse-related trauma theory, this thesis explores the wellbeing outcomes and impacts for child abuse survivors who create and view autobiographical documentaries that represent discourses about child abuse, intergenerational trauma, and healing. Adopting an anti-pathologising approach to trauma, this thesis explores and amplifies the historically silenced voices of child abuse survivors. Life is given to the underrepresented experiential accounts of autobiographical documentarians, with a focus on an uncharted community of practitioners: survivor-filmmakers. Further elevating survivor narratives, I position myself as a survivor-researcher, embracing an autoethnographic approach wherein my ‘presence’ remains integral to the research (Ellis et al., 2000; Bochner et al., 2016; Bochner, 2022; 2016). As a secondary research focus, this thesis seeks to understand what affordances survivor-researchers may bring to research projects that explore the experiences of child abuse survivors. A tripartite model for analysis of audio-visual texts frames the exploration, spanning three domains: production, text, and (potential) audience reception (Thompson, 1990). Trauma-and-violence-informed interviews were conducted to investigate the experiences of four survivor-filmmakers: Gwen van de Pas (Groomed, 2021); Tracey Arcabasso Smith (Relative, 2022); Jasmín Mara López (Silent Beauty, 2022); and Ginene Humphrey (Dandelions, TBC). Audio-visual methods of textual analysis, critical discourse analysis (Fairclough, 1992a; 1992b; 1998; 2001), and affect analysis (Rose, 2016; Tait, 2016; Plantinga & Tan, 2007) were applied to identify affordances and examine the discursive functionality of the documentaries. Interviews with wellbeing professionals were conducted to investigate the potential therapeutic value of the texts for survivor-viewers. Interview transcripts were analysed using reflexive thematic analysis (Braun et al., 2022a; 2022b; 2019). Synthesising the findings across the three domains, the research reveals how autobiographical documentary filmmaking and viewing can function as therapeutic healing tools, affording survivor-filmmakers and survivor-viewers the ability to re/process, challenge and let go of shame – a central aspect of the survivor experience, perpetuated and reinforced by victim-blaming culture. The filmmaking process functions as a ‘platform of vulnerability’ for survivor-filmmakers, a double-edged sword where traumatic stress and retraumatisation can be evoked, and where shame can be challenged. Challenging shame occurs through therapeutically impacting other survivors, experiencing survivorship, and re/processing in a myriad of ways, which engagement with representational strategies helps afford (including reenactments to represent traumatic memories and the child self, animation to represent, connect with and re-parent the inner-child, and using ocean imagery and sound as a mode of cultural memory). Post-release, autobiographical documentaries about abuse and healing may function as ‘collective healing artefacts,’ taking on an immortal life of their own that leads to ongoing therapeutic impact for survivors. The concept ‘vicarious therapy’ is coined to encapsulate how survivor-viewers may vicariously experience therapeutic impact, such as gaining a sense of survivorship, and re/processing possibilities of traumatic growth. This occurs through the intertwined processes of witnessing and feeling survivors – the elicitation of memories and affect(s) – and how autobiographical documentary representations can speak survivors’ shared language of shame. In other words, they can authentically represent aspects of the survivor experience. Contrasting individualistic healing approaches that dominate mainstream therapeutic practice, the findings magnify the value of collective approaches to heal abuse related trauma and shame. Autobiographical documentary filmmaking, and cinematherapy utilising autobiographical documentaries, may function as tools of collective healing. Findings suggest the need to move towards shame-sensitive approaches to autobiographical documentary filmmaking, building on the trauma-informed guidelines created by the Documentary Accountability Working Group (2022).
Love Letter : A study of South Asian Women, and their relationships with Māori and other racialised Women in Aotearoa
(The University of Waikato, 2025) Alam-Simmons, Ara; Waitoki, Waikaremoana; Rata, Arama; Roa, Thomas
This project records the experiences of South Asian women in Aotearoa, New Zealand, and what those experiences reveal about the possibilities and limits of solidarity with Māori and other racialised women under conditions of settler colonialism and white supremacy. This work is a response to my own relational experiences as a South Asian woman living in Aotearoa, and to the conversations that have emerged from years of active community involvement. This project centres women's voices through the lens of Indigenous, Black, and women-of-colour feminist thinking and praxis. Using a toolkit methodology comprising collaging, one-to-one conversations, found poetry, and autoethnography, the study engaged fifteen South Asian women across three interconnected sites of inquiry. The first explored how South Asian women make sense of their own experiences of colonisation and what it might mean to reclaim identity outside of colonial narratives. The second took a look at women's relationships with other racialised women, including Māori women, to understand what those relationships reveal about the conditions under which solidarity becomes possible, conditional, or foreclosed. The third drew on my own autoethnographic account to illuminate how deliberate acts of remembering, unsettling colonial narratives, resisting co-optation, and being in solidarity can function as a decolonial practice grounded in relational accountability to Māori sovereignty and Te Tiriti o Waitangi. The central empirical finding of this thesis is that solidarity among South Asian women and between South Asian women and Māori is not a natural outcome of shared marginalisation or identity. It is a relational practice that is structured, conditional, and sometimes foreclosed by the intersecting dynamics of settler colonialism, caste supremacy, heteropatriarchy, biculturalism, and internalised colonial narratives. Key findings demonstrate that solidarity requires, first, an internal reckoning: healing from internalised oppression, reclaiming ancestral histories, cultural practices, language, and knowledge systems, and developing critical consciousness of complicity within settler-colonial structures. Second, it requires an external and political commitment: confronting caste supremacy within South Asian communities, refusing model minority positioning, and grounding relationships that engages in a political committment to Te Ao Māori and Māori sovereignty, rather than in the false promise of inclusion within settler-colonial frameworks. Additionally, this thesis, locates caste supremacy in Aotearoa, New Zealand. This thesis makes both an empirical and methodological contribution to the Asian-Indigenous solidarities literature. Methodologically, it demonstrates that arts-based approaches can make visible the complexity and diversity of South Asian women's relational lives in ways that conventional qualitative research cannot, offering a practical toolkit that can be taken up in community and activist spaces beyond the university. Conceptually, it offers two frameworks as new contributions to the decolonial solidarities literature. The first extends the whakawhanaungatanga framework developed by Rata and Al-Asaad (2019) by adding two new dimensions. These are restoration, which centres the reclaiming of identity, healing, and spiritual practice as political acts; and reconstruction, which names the need for joint political struggle as the governing horizon of solidarity. The second is a decolonial framework developed through the autoethnographic inquiry. This is made up of four interconnected dimensions: historical remembering, unsettling settler colonial narratives, resisting co-optation, and being in solidarity that is led by Te Ao Māori and accountable to Māori sovereignty. Together, these frameworks offer South Asian and other tauiwi of colour communities practical and political pathways for building solidarities that refuse settler-colonial logics and actively contribute to creating more just and relational ways of living together in Aotearoa.
Outcomes of cemented and hybrid primary total hip arthroplasty in osteoarthritis: A New Zealand regional study
(The University of Waikato, 2026) Pearce, Amy; Hebert-Losier, Kim; Joshi, Chaitanya
Introduction: Primary total hip arthroplasty (THA) for osteoarthritis (OA) success is typically assessed using implant survival as the primary outcome; however, revision surgery alone underestimates the true burden of suboptimal outcomes (e.g., pain or poor function). Secondary outcomes, or patient-reported outcomes (PROMs), therefore provide a complementary assessment of THA success. During the last two decades, fully cemented THAs have been progressively replaced by uncemented ones, despite limited long-term comparative evidence. Although national registry data allow analysis of broad implant category types, they may lack implant and PROM detail compared to regional registries. This Thesis evaluates whether changes in implant design and fixation strategy have translated into significant and meaningful improvements in implant survival and patient outcomes in the Bay of Plenty region of Aotearoa New Zealand (NZ). Aims: This Thesis aimed to evaluate long-term survival and PROMs of an early generation cemented, modern cemented, and modern hybrid primary THA for OA, and identify patient factors or funding source associated with these outcomes. The work first synthesised existing evidence comparing cemented and hybrid fixation. It then compared survival between the earlier generation THA and its modern cemented successor of the same lineage. Thereafter, the work identified long-term PROMs in earlier generation cemented THA and then compared 10-year PROMs between the two cemented THA generations. Finally, survival and PROM outcomes of the hybrid THA were compared with the modern cemented. Influential patient and funding factors of primary and secondary outcomes were identified across all studies. Methods: This Thesis comprised a systematic literature review and linked retrospective cohort studies using prospectively collected arthroplasty survival and PROM data from the NZ joint registry (NZJR) and Tauranga Orthopaedic Research Inc. registry for the Bay of Plenty region. Patients undergoing primary THA for OA between 2003 to 2023 with earlier generation cemented, modern cemented, or modern hybrid THAs were included. PROMs included the Oxford Hip Score (OHS), McMaster University Osteoarthritis index (WOMAC), and Veterans Rand 12-item health survey (VR-12). Baseline differences were addressed using propensity score weighting. Implant survival was analysed using Cox regression, and PROMs were analysed longitudinally including changes from baseline. Multivariable models examined the influence of sex, ethnicity, age at surgery, body mass index (BMI), American Anesthesiologist Society (ASA) rating, and funding source (public versus private) on outcomes. Results: In the literature, five studies compared survival and three compared PROMs between cemented and hybrid primary THA for OA. Survival outcomes were no different between THAs in three studies, but cemented survival was superior in two studies. PROMs were no different in the three available studies.
“Eles Deturpam o Que Tu És”: Coloniality, resistance, and the reconfiguration of colonial power in Quilombos of Amapá, Brazil
(The University of Waikato, 2026) Farias da Silva, Brenda; Norris, Adele N.
This thesis examines the persistence and reconfiguration of colonial structures in Brazil’s northern region, focusing on the state of Amapá – a critical borderland of Amazonian modernity. With a particular focus on Quilombos (formerly-enslaved Black settlements), it addresses the central argument that coloniality, understood as the enduring matrix of power, race, and knowledge established during the European conquest, continues to shape the present. While state and corporate narratives portray the Amazon region as a site of sustainable progress, this study aims to demonstrate how colonial logics of isolation, extractivism, and silencing persist under the banner of development and conservation. A decolonial and interpretive methodology combining qualitative semi-structured interviews was employed to answer three interrelated questions: (1) How have colonial structures of racial, spatial, and epistemic domination persisted and been reconfigured in Brazil’s northern region, particularly in Amapá? (2) How do Quilombola women from Amapá experience and resist intersecting forms of racialized labor and territorial dispossession? (3) How do decolonial frameworks enhance our understanding of the relationship between racial capitalism, gendered violence, and the afterlives of slavery in northern Brazil? Participants’ narratives, practices, and silences were analyzed as contributions to theorize coloniality, survival, and epistemic disobedience. The findings reveal that racial capitalism in Amapá operates not only through extractive economies but also through established colonial regimes that devalue subaltern knowledge while maintaining racial hierarchies. The legacies of historical servitude and land dispossession persist through bureaucratic omission and policy frameworks that privilege private and corporate interests over collective rights. In response, communities articulate diverse forms of resistance that merge political action, cultural continuity, and strategic silence. Ultimately, this thesis argues that decolonial practices are not abstract ideals but lived behaviors emerging from the endurance and creativity of those who continue to resist distortion and erasure. Research findings contribute to decolonial theory by reterritorializing coloniality within the Amazonian frontier and advancing a decolonial research praxis grounded in ethical rigor, linguistic fidelity, and co-produced knowledge. Findings offer critical insight into how racial capitalism and epistemic domination are contested through localized acts of survival, reinterpretation, and creation.
Pictures in the substantiation of organisation: a study of radiology
(The University of Waikato, 1992) McArthur, William; Bettison, David; Goldsmith, Michael
The motivation for this study is an interest in technologically produced imagery and its effect on the contemporary world. Natural events, pictures, diagrams, paintings, spectacular performing arts, icons, etc, are persistent features in the repertoire of language for expressing and constituting knowledge. Much of present day common sense knowledge, however, is constituted through observation made in direct, yet technologically mediated ways. From television to computer graphics and radiographs, a plethora of technologies offer visual experience of a kind available only through techno-scientific means. Using technical instruments requires constructs created by user’s and see-er’s. Language that evolves, is often interpretable only through a unique cultural practice dependent on expertise. Technically produced imagery raises issues of individual and collective interpretation. The thesis method is eclectic to discern the complexity this involves. Intertwining of technical and scientific modes of professional conduct is examined through the implication of Galilean discovery, by way of the technical effects of glass in the 17th Century, and Roentgen’s accidental discovery through x-rays in the late 19th Century. Field work centers on issues pertinent to technologically mediated knowledge. This involved a small group of radiologists in the hospital of a provincial New Zealand city. Engaged variously in difficult radiographic interpretation, they are teaching newly qualified doctors entering the radiological profession to successfully “see” the imagery evoked by the radiograph. Medical practitioners, and especially radiologists, are a profession required specifically to develop skills of image and sign interpretation. Fundamental to their accountability is intersubjective agreement on what is “seen” on a radiograph and other technical equipment. The third dimension of “depth” has to be accurately imputed to a two dimensional radiograph. Radiological “objectivity” is the outcome of collective discourse. Central to this discourse is a specific employment of particular metaphors. Metaphorical transferrence occurs during the process of diagnosis as the interpreter moves between what is seen on the radiograph and his or her medical repertoire. Diagnosis through the inspection of visual items involves the skilled (but often intuitive) decoding of complex systems of iconic and symbolic (conventional, arbitrary) signs. Diagnosis is sanctioned by collective agreement accomplished through dialogue. The basis of the radiological code is an inextricable use of metaphor and metonymy in the syntagmatic construction of an image. The nature of what is seen on the radiograph is based on the notion of caricature. This implies that the person who can interpret a radiograph is able to “see” in it the embodiment of some image which may be completely obscure to the uninitiated. Caricature interpretation is fundamental to constituting the typifications of daily life. This has particular significance in what might be termed a “techno visual” life-world.
A systems analysis of an area mental health service
(The University of Waikato, 1992) Keith, Catherine B.
The mental health services existing in a defined geographic area in New Zealand were studied in an effort to establish priorities for service development. It was clear from a preliminary review of the services that while community based services were operating in the area, they were under-resourced and very poorly monitored. They did not provide care that was comprehensive and the population they were intended to service was not clearly specified. Information about who used the services, where they came from and why, was difficult to obtain. There were no psychiatric beds in the general hospital in the area which served a population of approximately 300,000. Acute inpatient care was provided in a 300 bed psychiatric hospital remote from the main centres of population. The acute area of this hospital provided 50 beds and appeared to be under strain most of the time. No standardised criteria for admission and discharge to and from the service were in place. The aims of the acute service, the boundaries of clinical responsibility between assessment, symptom control, treatment and continuing care were vague. To begin the study, a scale was developed and used to assess the feasibility of evaluating individual psychiatric services. A one day census of patients registered with the services was then carried out. The services included inpatient services, general hospital and court liaison services, community mental health centres, day hospital programmes, domicilliary nursing services, a substance abuse service, a rapid assessment service and a child and family service. The census uncovered a lack of adequate record systems for both patient and management information. As a consequence, a patient case register, based on a minimum data set of patient information, was developed. Meantime, a preliminary review of the acute services in the psychiatric hospital revealed a service under stress. Major sources of this stress were identified as inadequacies in the physical environment and a large and apparently uncontrollable variation in amount of service use by individuals admitted to the acute area. In the last phase of the research, the problem of uncontrollable variance in amount of acute inpatient service use was examined. This focus on acute inpatient care was justified because it was the most restrictive and expensive form of care offered and there was clearly a need to describe and explain how this service worked and whether it was cost effective. A study of five hundred and thirty eight people admitted to the acute inpatient service during 1988 was designed to determine the factors which predicted amount of service use. An instrument was constructed to record information on selected predictor variables. The instrument was built around the registration form developed in the process of establishing the patient information system. Predictor variables were chosen from an extensive literature review of factors determining service use, and from clinical and management opinion on what information was most necessary for service development and clinical management. Choices were also made to include information which was being gathered at the time, albeit unsystematically, by existing clinical history taking and admission and discharge procedures. The research method involved selecting a comprehensive range of predictor variables as potential indicators for amount of acute psychiatric service use, and dividing them into systems variables, which were by definition outside the control of the patient, socio-economic variables and behavioural variables which were consumer characteristics. A range of socioeconomic, systems and behavioural variables was approved for inclusion in the study by the researcher, clinicians and management. These variables were measured and related to the criterion variable, amount of service use (ASU). The criterion (ASU) was defined as number of bed days spent in the acute inpatient service during a twelve month period. Variables categorised as systems variables (environmental and service features over which the consumer had no control), were found to be the strongest predictors of service use, compared to sociodemographic factors or behavioural characteristics of the users. This suggested that the system of service was provider rather than consumer driven. The results also indicated that, in the absence of evidence to support the effectiveness of acute inpatient care, there was a need to develop alternatives. There was an equally urgent need to implement evaluation procedures which will begin to measure the effectiveness of care delivered in all mental health service settings. The methods developed in this thesis (to determine evaluation feasibility, to develop a client case register, to determine predictor variables for amount of service use) resulted in a useful general model which can be used to describe, explain and to some extent predict and control patterns of human service use in a variety of settings. The theoretical underpinnings for the work, which were originally derived from general systems theory, from the discipline of evaluation research and from the community psychology literature, are strengthened and endorsed by the results. The data obtained extend the case register system developed in the early phases of the project to provide a substantial foundation on which to build a comprehensive data base. This can be regularly updated and expanded allowing for ongoing service evaluation. For the first time in the region, clinical and service policy decisions can be based on information which is both objective and reliable.
Studies in the importance of accounting in New Zealand: a Foucauldian perspective
(The University of Waikato, 1992) Hooper, Keith; Lawrence, Stewart R.; Pratt, Michael
The aim of this thesis is to illustrate from three constructed cases why and how some knowledges that have been marginal (like accounting before the nineteenth century) become powerful (Hoskin and Macve, 1991, p. 10). In other words, to explain from a New Zealand context why and how the practice and profession of accounting grew to be so influential and important in relation to its comparatively humble 18th century bookkeeping and clerical origins. It is argued that the practice of accounting became more important in the nineteenth century because such practice facilitated the exercise of power and discipline in the context of a growing, European dominated society. According to Foucault (1977) the new human disciplines (e.g. medicine, law accounting, etc.) which appeared in the eighteenth and nineteenth centuries were not the product of emergent economic needs but rather the product of new disciplinary powers. Moreover, the importance of such new disciplines, Foucault (1977) claimed, should not be traced in a linear fashion relating, for example, legislation and institutional development, but from a postmodern perspective stressing diffuse and contingent origins. In other words, no single source of origin can fully explain such phenomena. The three studies examined in this thesis are not meant to be representative or necessarily typical of contemporary practice, rather they serve to illustrate the diffuse and separate sources of accounting’s power origins within a New Zealand. From the 1860s, three events took place which were to change the social and commercial structure of the new colony: the passing of the first New Zealand Companies Act 1860, the Native Lands Settlement Act 1865 (which individualised Māori land titles and permitted direct European purchase), and large scale European immigration into New Zealand. The colony during this period changed from a Māori dominated economy based on tribal ownership of land to a European capitalist economy based on individual land ownership. With limited manufacturing capacity and few mineral resources, land was the basis of wealth and economic power in New Zealand. The period from 1870 to 1930 was crucial because it was during those years that most land in New Zealand was transferred from Māori to European ownership. The common theme shared by the three separate cases depicted in this thesis is that to a greater or lesser extent they are about conflict over land - its acquisition and the power and wealth its ownership conveys. The overall aim is to provide a critical history of accounting in New Zealand in Foucauldian terms, and to provide an explanation of the present by tracing its genealogy. To achieve this end some consideration of New Zealand’s history is necessary and, in particular, the importance of the Treaty of Waitangi to New Zealand society. The cases are suited to a Foucauldian interpretation because they represent local, discontinuous histories concerning struggle and insurrection, elements which Foucault considered to be vital for genealogical research. The first case study (of three) examined in this thesis demonstrates how land was transferred to individual European ownership and the part played by an accountant and other professionals in executing land transactions. It also illustrates the close conceptual links of accounting practice with European values such as capital accumulation and shows how an accountant was able to use his knowledge to advance his employer/client’s interests. Thus the former explains the character of the discursive practices of accounting, while the latter illustrates how accounting practice served the ends of the ascendant power structure. The second case study continues to develop these themes by exploring the history of company formation in colonial New Zealand. The emphasis is on conflict between directors and shareholders and in particular the struggle for control of a land company. The study depicts the way in which the privileged use of accounting knowledge may serve the particular interests of a powerful business elite. The final study depicts the activities of a practising public accountant acting for an overseas client. Once again two themes are apparent: accounting as an instrument of European capital accumulation, and accounting as a modern power discipline. The latter theme explaining how power may be exercised. Research for these studies was conducted in various national archives containing collections of private papers. Use was also made of past newspaper accounts of company meetings and contemporary commentaries on business affairs. Secondary sources were used extensively in the first four chapters to furnish background material relevant to the themes and arguments developed.
Lateral electron disequilibrium in radiotherapy treatment planning
(The University of Waikato, 1991) Hoban, Peter William; Round, W. Howell
Lateral electron disequilibrium on the central-axis of small-diameter circular beams is investigated using the EGS4 Monte Carlo system, for 10 MV photons. Monte Carlo results generated using the reciprocity technique are presented. In water, disequilibrium is found to occur for beams with diameters of less than approximately 4 cm. In lung of density 0.25 g cm⁻³, disequilibrium occurs for diameters less than approximately 16 cm. The lateral electron equilibrium factor is defined and used to quantify the degree of disequilibrium. Convolution dose calculation for 10 MV photons, using polyenergetic energy deposition kernels, gives a slight error in central-axis dose, due to beam hardening with depth. Primary and scattered polyenergetic kernels formed for a surface primary photon spectrum contain less and more fractional energy respectively than primary and scattered kernels formed for a beam hardened spectrum. A beam hardening correction to the kernels used in the convolution is proposed. This correction improves the agreement of convolution results with Monte Carlo predictions. A superposition algorithm is developed and used to calculate dose in a lung phantom for 10 MV photons. Results show an overestimate in dose in the lung for a 5 cm square field when compared with experiment and Monte Carlo results. Disagreement is due to the assumption made in the density scaling method that secondary electrons travel in straight lines. A modification to the interaction voxel weighting in the density scaling procedure improves the result. The superposition method for 4 MV and 10 MV photons has been incorporated into the GRATIS treatment planning system. Two and three-dimensional electron pencil beam algorithms are used to calculate the dose distribution in a water medium containing a small cavity for a 12 MeV electron beam. The measured hot spot beneath the cavity is 122%. The 2-D method predicts 114% and the 3-D method predicts 127%. Both profile and depth dose curves produced by the 3-D method are superior to those produced by the 2-D method. The 3-D pencil beam algorithm has been incorporated into the GRATIS treatment planning system.
Oxygen control of nitrogen fixation in Frankia and Coriaria arborea
(The University of Waikato, 1992) Harris, Sharon L.; Silvester, Warwick B.
Oxygen has a central role in regulation of nitrogen fixation activity in both asymbiotic Frankia and Frankia - actinorhizal plant symbioses. Daily addition of fresh medium at a low dilution rate (D=0.125 day⁻¹) allowed Frankia to be maintained in continuous culture with a stable rate of growth and nitrogenase activity for periods of more than 30 days. Use of continuous cultures permitted the effects of oxygen on vesicle morphology and nitrogenase activity to be investigated independent of normal developmental changes occurring in batch culture. Frankia grown at higher oxygen concentrations formed thicker-walled vesicles which allowed adaptation of nitrogenase activity over a pO₂ range of 5 - 40 kPa O₂. Recovery of nitrogenase activity after oxygen shock (2 to 21 kPa O₂) followed formation of thicker-walled vesicles. Vesicle walls also showed a thickening response to pO₂ level under conditions where nitrogenase activity was inhibited (in Ar : O₂ atmospheres) or not detected (in cultures grown on nitrate-containing medium). These results indicated the presence of vesicles and the induction of nitrogenase activity in culture is not as synonymous as was originally believed. GC/MS analysis of lipid extracts from Frankia cultures and actinorhizal nodules confirmed the high hopanoid content of Frankia. Differences in the relative proportions of hopanoids present were also detected between samples and the total amount of hopanoids measured in Frankia cultures was slightly higher at higher oxygen concentrations. Most work on Frankia symbioses focussed on the Coriaria arborea association and highlighted startling similarities between this actinorhizal symbiosis and Rhizobium - legume associations. Coriaria showed a legume-like, non-recoverable decline in nitrogenase activity and nodule respiration following exposure to 10 kPa acetylene or argon. The extent of the acetylene-induced decline was diminished with increasing plant age and adaptation to above atmospheric oxygen concentrations. Lag-phase measurements indicated acetylene-induced declines in Coriaria are due to an apparent increase in nodule diffusion resistance which has also been observed in legumes. Defoliation of Coriaria also caused a decline in nitrogenase and respiratory activity associated with an apparent increase in nodule diffusion resistance although the effect was delayed for approximately two hours. Continuous flow assay of nitrogenase activity in several actinorhizal species and one legume, exposed to alternate gas streams of nitrogen and helium at varying oxygen tensions, indicated a small component of the diffusion pathway in Coriaria arborea and Myrica gale nodules is an air-filled pathway. In Alnus glutinosa, Casuarina cunninghamiana and Medicago sativa nodules the diffusion pathway has some “water-filled” or “solid” diffusion barrier. Speculation is offered on the location and functioning of fixed and variable diffusion resistance in Coriaria nodules based on results from this study and previous work.
“Going native”: a case study of cultural appropriation in a settler society, with particular reference to the activities of Johannes Andersen in New Zealand during the first half of the twentieth century
(The University of Waikato, 1992) Gibbons, Peter; Barber, Laurie; Hart, Philip; Simes, D.G.S.
One mode of ‘indigenization’ in settler societies is cultural appropriation. This involves the utilisation of elements of the culture of the indigenous peoples by incorporating these elements in the signifying systems of the settler society, without the authorisation of the indigenes. The present study exemplifies some of the discursive strategies of cultural appropriation employed by the settler society in New Zealand through focusing on the activities of Johannes Andersen (1873-1962) in the first half of the twentieth century. In seeking to authenticate himself as an autochthonous New Zealander, Andersen, like other Pakeha around 1900, turned to Maori subjects for prose, verse, and art. His knowledge of Maori culture was derived from books, not from contact with Maori people. After the Great War, encouraged by the prominent ethnologist Elsdon Best, and with the collaboration and authorisation of Maori, especially Apirana Ngata, who sought assistance from sympathetic Pakeha, Andersen recorded traditional lore during four brief visits to Maori communities. This was the limit of his close contact with Maori people, but it provided much of the basis for his reputation among Pakeha as an authority on the Maori, an authority emphasized by his books, lectures, and broadcasts, in which he encouraged other Pakeha to develop an interest in Maori subjects. Many Pakeha came to ‘know’ the Maori through the reductive constructions of authoritative commentators such as Andersen. Andersen’s influence extended to scholarly anthropological circles through his editorship of the Polynesian Society Journal. As editor he privileged versions of New Zealand traditional history which accorded with his own intellectual preferences, and deflected revisionist interpretations. The divergence between Ngata’s hope of enlisting the aid of Pakeha for Maori purposes and Pakeha desire to appropriate Maori cultural resources for their own use, is particularly evident in the case of Nga Moteatea, the classic collection of Maori ‘songs’. Andersen, whose failure to learn the Maori language blocked his access to the material, persuaded Ngata to prepare a bilingual version. He also attempted to invest the translated ‘songs’ with those qualities which he considered to characterise English literature. Shortly thereafter, Ngata, critical of a range of Andersen’s activities, acquiesced in a move by Pakeha critics of Andersen to replace him as editor of the Polynesian Society Journal. Andersen was but one of many Pakeha who incorporated aspects of Maori culture into Pakeha signifying systems in an attempt to develop a sense of identity. The practice has significant implications for intercultural relationships, and in recent decades some Maori have expressed resistance to cultural appropriation.
Innovation in science curriculum a Sierra Leone case study
(The University of Waikato, 1991) Baimba, Andrew Augustine; Katterns, Robert; Kirkwood, Valda
Recent studies in philosophy of science and learning theory have identified elements that add a socio-cultural dimension to science curriculum debates. These suggest that effective science education must take account of the culture in which it is being offered. Accordingly, the present study conducted in Sierra Leone investigated the viability of a junior secondary school science curriculum that took into account the childrens’ traditional culture. The investigation involved two parts. The first was a case study examining the present state of junior secondary school science education in Sierra Leone using data derived from a survey which canvassed teachers’ perceptions of science and students’ attitudes towards it. The second involved action research in which a group of teachers worked with the researcher to develop, trial and self-evaluate teaching packages in physics based on the Science for All curriculum, an approach that is based on the constructivist view of learning. The main intent of the study was to investigate first, the effects on their professional development of the teachers’ interaction with the new curriculum and, secondly, their students’ attitudes towards science. The research instruments employed were interviews, classroom observation and an attitudes to science questionnaire. The initial case study showed that the present junior secondary school science programme in Sierra Leone was characterised by: 1. Unfavourable students’ attitudes towards science. 2. Low numbers of General Science teachers with subject expertise in Physics and Chemistry. 3. A lack of sense of direction in determining goals and objectives. 4. Inadequate pre-service teacher education preparation. 5. Limited teacher understanding of recent changes in the thinking about the nature of science and the ways of acquiring scientific knowledge. Successful use of the new curriculum to overcome these problems was hindered by the teachers’ scepticism about the new curriculum, a gap between their theoretical and practical understanding of the change process, and insufficient skills to implement the revised curriculum. Techniques employed to alleviate these problems during the action research suggested that teachers’ commitment could be increased by clarifying conceptually the need for innovation. The researcher’s support and encouragement throughout the curriculum trials significantly helped teachers to give practical expression to their theoretical understanding of the change process. Action research with the new curriculum brought about major changes in the teachers’ approach to teaching. They showed evidence of appreciating recent constructivist views about the nature of science and the ways of acquiring scientific knowledge. The development of their own effective and more relevant curriculum also enhanced the teachers’ self esteem. But even though the teachers with their new found confidence believed otherwise, post-test results showed that students’ attitudes to science were not enhanced by their interaction with the new curriculum. The results of the study suggest policy implications for Sierra Leone. The educational system and science curricula need to dwell far less on western-type syllabuses and public examinations and develop instead science curricula that bridge school science and students’ everyday application of scientific ideas in their traditional settings. Nevertheless, much research is required to identify cultural aspects that can be linked to the school science curriculum. Concomitantly, there is need to research the viability of both preservice and inservice teacher education programmes that can bring about the bridging referred to. The present action research study is a beginning.
The influence of subsoiling on soil physical properties and pasture production
(The University of Waikato, 1992) Chapman, Richard; Allbrook, R.F.
In many areas of New Zealand, soils under pasture have become compacted by a combination of livestock trampling, use of heavy machinery and natural processes, or in the case of sports fields, heavy use at high moisture levels. These processes create soil horizons that have a high resistance to a penetrometer, often a high bulk density and hence a lowered porosity. These horizons reduce hydraulic conductivity, change soil moisture characteristics and restrict root elongation and consequent pasture yield. An arable type subsoiler was re-designed for pasture use and its effects on five soils in the Hamilton Basin were investigated. Soil disturbance was assessed for differing operational depths, tip sizes, operating modes and soil moistures. Soil physical characteristics such as bulk density, soil strength, pore space, water tension and infiltration were measured at intervals after subsoiling. Root growth and yield response of pasture were quantified. Subsoiling in the vibrating mode under relatively dry soil conditions increased soil disturbance by 30% in comparison with non-vibrating; wide tips in comparison with narrow tips increased disturbance by up to 100%. Results indicated that the effectiveness of subsoiling at a standard speed, is a function of operational depth, tip size, pitch angle, soil type and soil moisture. Generally subsoiling below 45 cm depth resulted in a reduction in soil disturbance and was less effective under wet soil conditions at deeper than 35cm Increased water stress in and around the subsoiled slot resulted from summer subsoiling. The addition of press rollers reduced evaporation and reduced ground heave by 25%. Measurements of ground heave following subsoiling using a purpose built heaveometer enabled comparisons between different soils to be made. The more clayey Hamilton and Whatawhata soils showed greatest heave. Subsoiling reduced bulk density by up to 30% within 10 cm distance of the subsoil slot; significantly reduced levels were sustained at this distance in the more clayey soils for up to two years. The effect on bulk density decreased with distance from the subsoil slot. Bulk density estimations in situ showed greater changes in response to subsoiling than laboratory measurements. Penetrometer measurements provided additional crucial information on the extent of soil disturbance and its sustainability with time. Repeated measurements defined “envelopes” of soil disturbance emanating from the subsoiled shank and tip. The lowest soil penetration resistance was found down the slot, where strengths were commonly reduced from 4 MPa to 1 MPa. The depth of influence was shallower further from the slot following a 45 - 50° angle up from the subsoiler tip to the surface. In the more clayey soils a discrete zone of higher strength soil was occasionally identified contiguous to the lateral extremeties of disturbance. Subsoiling shattered large aggregates thus creating a larger volume of soil. Soil mixing was limited to a relatively small area around the subsoiler shank and tip where 17 - 19% of A and B horizon aggregates interchanged. Consequently a redistribution of soil texture and organic matter occurred within soil profiles. Pores >9.76 μm increased from 20 to 35% in A horizons and from 3 to 35% in B horizons. Increased porosity to the full depth of soil disturbance resulted in rapid movement of excess summer rain, and in the case of the poorly drained Whatawhata soil drier soil conditions prevailed in winter. Measurements of root elongation, together with SEM analysis showed that grass roots had difficulty penetrating high bulk density (1.35 - 1.50 Mg m⁻³), high strength (>5.00 MPa) soil layers. In these cases subsoiling facilitated increases of up to 20% in root length and a consequent increase in pasture yield of up to 17.7%. The more clayey soils derived greater benefits from subsoiling than sandy soils, both in the extent of soil disturbance and duration of reduced bulk density and soil strength. In the case of an artificially constructed soil, near surface compaction was ameliorated with a consequent improvement in turf. Provided that subsoiling was carried out under optimum conditions, a positive response in pasture yield could be expected, even where soil physical properties were not limiting. Re-compaction rates following subsoiling are a function of pasture management and soil physical properties, but provided subsoiling is carried out with optimal soil disturbance, then a subsoiling frequency of two years for sandy soils and three years for more silty and clayey soils is recommended.
Characterisation and fate of bleached kraft mill effluents from a New Zealand pulp and paper mill
(The University of Waikato, 1990) Stuthridge, Trevor Raymond; Langdon, Alan G.; Wilkins, Alistair L.
The wastewater discharges from the Kinleith mill, a New Zealand integrated bleached kraft pulp and paper mill, were characterised and their treatability assessed. The chlorination stage bleaching effluents from the mill’s second bleach plant [(C30D70)EoDED sequence] contained a group of novel chlorinated compounds. Fourteen compounds were isolated from the effluents by a combination of liquid-liquid extraction, column chromatography, and preparative gas chromatography. Mass spectral and ¹H and ¹³C NMR data showed these compounds to be hydroxylated and/or chlorinated derivatives of Pinus radiata monoterpenes. The major compounds were a dichlorobornane and four dichloro-p-menthane-1,8-diols. The chlorinated monoterpenes were detected in total concentrations of 1400-12 300 μg L⁻¹ [70-600 g air-dried tonne⁻¹ (ADT) bleached pulp] and they were the major class of low molecular weight extractable organic compounds present in the chlorination stage effluent. The principal factor determining their formation appeared to be the high concentration of monoterpenes remaining in the Pinus radiata brown stock produced in the mill’s continuous digester. The biological activity of the chlorinated monoterpenes was assessed. The chlorinated monoterpene alcohols were base labile with a 94% decrease in concentration being observed within 4 hours at pH 12. The chlorinated monoterpene hydrocarbons exhibited a lesser degree of alkaline lability. Acute toxicity tests on the monoterpene alcohols gave EC₅₀ concentrations of 60-200 mg L⁻¹, indicating that these compounds display relatively little toxicity. The monoterpene alcohols were also tested for mutagenicity and genotoxicity. Some of these compounds produced mutagenic and genotoxic responses. An assessment of the bioaccumulation potential of the chlorinated monoterpene alcohols showed them to have log Kₒw values of 1.37-2.1. Therefore, these compounds are unlikely to exhibit a significant bioaccumulation propensity. Treatment of the chlorination stage effluents in an aerated lagoon treatment system removed 80% of the chlorinated monoterpene alcohols but only a small fraction of the monoterpene hydrocarbons. It was concluded that these compounds were unlikely to produce significant environmental effects in the recipient. The mill has two secondary treatment systems. The relative effectiveness of each of these was assessed. The two systems operate in different configurations. Treatment system A, which receives general mill wastewaters and chlorination stage bleaching discharges utilises deep, aerated lagoons and has a 4.5 day retention time. Treatment system B, which receives alkali extraction bleaching wastewaters and foul condensates, uses a lagoon system with a retention time of 51 days. Detailed chemical analyses of the untreated and treated wastewaters were made. Mass balances were calculated for a range of physical parameters and for specific chlorinated and non-chlorinated organic constituents. Significant differences in the treatability of various constituents were found. In particular, while system A was able to reduce levels of adsorbable organic halide (AOX) by 65%, no significant reduction in AOX occurred in system B. In contrast, system B reduced levels of chloroacetic acids by 84% while system A did not achieve any statistically significant removal of these compounds. The treatability of chlorophenolic compounds also differed. System A was unable to remove chlorophenols and chloroguaiacols while system B did not reduce levels of chlorocatechols. The removal of AOX from effluents treated in system A was high compared to published data and an assessment was made of possible mechanisms for the observed AOX removal. Much of this removal took place in a short section (3.3 hr residence time) of the system’s main lagoon. The initial AOX decrease in the aqueous phase could be achieved in part by settling of AOX-containing suspended solids from the influent wastewaters. In addition, lime and bacterial solids present in the treatment system were able to adsorb AOX from the influent wastewaters. Only a small proportion of the organic chlorine removed was found in sludges. A mass balance of aqueous and solid phases indicated that over 99% of the removed AOX was mineralised.
Control of glucose and xylose utilization by Clostridium thermohydrosulfuricum Rt8.B1
(The University of Waikato, 1992) Cook, Gregory Murray; Morgan, Hugh W.; Janssen, P.H.
Five extremely thermophilic organisms representing the Eubacterial and Archaebacterial Kingdoms were studied for controlled expression of β-galactosidase, β-glucosidase and α-glucosidase synthesis. Under the culture conditions used, these organisms exhibited a high constitutive level of enzyme synthesis which was modulated in the presence of added carbohydrate. The lack of observed classical induction in these organisms could either reflect a lack of control or a less elaborate control of enzyme synthesis, which may be advantageous to these bacteria in environments low in nutrients. This absence of highly regulated control is common in thermophilic organisms and may be a reflection of the limited evolutionary divergence of thermophiles as is suggested by phylogenetic studies. Cl. thermohydrosulfuricum Rt8.B1 inhabits thermophilic environments where the natural concentrations of sugars would be expected to be quite low. The results of this study demonstrated that glucose and xylose were used simultaneously i.e. the bacterium exhibited hyperbolic growth when both glucose and xylose were supplied together at nonlimiting concentrations. Under conditions of hyperbolic growth, Cl. thermohydrosulfuricum Rt8.B1 exhibited neither catabolite repression nor inducer exclusion. Although classical control mechanisms were not seen, the utilization of glucose and xylose were tightly controlled at both low and high concentrations of single and multiple substrates. Such regulation to allow controlled hyperbolic growth is consistent with the idea of Cl. thermohydrosulfuricum Rt8.B1 being well adapted as an opportunist. The transport of glucose and xylose across the bacterial cell membrane of Cl. thermohydrosulfuricum Rt8.B1 was governed by permeases which did not catalyze concomitant substrate transport and phosphorylation, and thus was not a phosphoenolpyruvate-dependent carbohydrate: phosphotransferase system. Glucose and xylose transport was not driven by a proton motive force (ΔμH⁺) nor coupled to sodium and potassium ion gradients. An involvement of ATP in the uptake process was indicated by the reduction of glucose and xylose uptake by iodoacetate and sodium fluoride, both inhibitors of ATP synthesis. The phosphorylation of glucose was carried out by a constitutive ATP-dependent glucokinase and that of xylose by an inducible ATP-dependent xylulokinase following isomerization by xylose isomerase. These enzymes not only initiated the metabolism of glucose and xylose in Cl. thermohydrosulfuricum Rt8.B1, but also served to “capture” sugars from the cytoplasm through their phosphorylation. Since glucokinase was regulated primarily by the concentration of ATP, ADP, and AMP, both glucose phosphorylation and uptake appeared to be dependent upon the energy status of the cell. Xylulose inhibited glucokinase activity, indicating that xylose metabolism may regulate the activity of glucokinase in glucose and xylose-grown cells. Xylose utilization by Cl. thermohydrosulfuricum Rt8.B1 was mediated by two systems. Both systems were inducible and dependent on the xylose concentration used for cell growth. Cells grown on 5 mM xylose had a high-affinity, low-capacity system for xylose uptake which was saturable (low Vₘₐₓ). Cells grown on 50 mM xylose had a low-affinity, high-capacity (high Vₘₐₓ) system for xylose uptake and the kinetics were indicative of facilitated diffusion. The xylose isomerase of Cl. thermohydrosulfuricum Rt8.B1 had a high Kₘ for xylose (low-affinity) and xylulokinase had a low Kₘ for xylose (high-affinity). The Kₘ for xylulokinase was lower than the Kₜ for the high-affinity xylose permease; this indicated that the xylulokinase phosphorylating system was fully saturated at external xylose concentrations near or above the Kₜ concentration for uptake and that the affinity of xylulokinase regulated both the rate of xylose uptake and its subsequent utilization. When Cl. thermohydrosulfuricum Rt8.B1 was grown on high concentrations of xylose (low-affinity), xylulose leaked from the cell. This indicated that a futile cycle for xylose may be operative under conditions of high xylose and may explain the facilitated diffusion kinetics observed. A semi-defined minimal medium for the growth of Clostridium thermohydrosulfuricum Rt8.B1 was developed in this study. This medium was able to support the growth of several thermophilic anaerobes. Most strains studied showed morphological changes. In one instance, spores were seen in an apparently nonsporulating strain of Thermoanaerobium brockii DSM 1457 which could not be attributed to a contaminant. This observation has resulted in the species being renamed Thermoanaerobacter brockii comb. nov. and the genus Thermoanaerobium being removed due to the removal of the type strain.
The fluvial biology of Lake Taupo rainbow trout
(The University of Waikato, 1991) Rosenau, Marvin Leslie; Chapman, M. Ann; Green, John D.; Swales, Steve
The riverine biology of adfluvial-lacustrine rainbow trout (Oncorhynchus mykiss, previously Salmo gairdneri) from the Waimarino, Tokaanu, and Hinemaiaia Rivers was investigated. These three streams are important spawning and rearing habitats for rainbow trout recruiting to an economically important sport fishery in Lake Taupo, New Zealand, yet each has very different bio-physical characteristics; the Waimarino River is an unregulated stream with seasonally varying flow and temperature regimes; the Hinemaiaia River is an hydro-electric flow-controlled stream having a seasonally varying temperature regime and daily flow fluctuations; the Tokaanu River is an unregulated groundwater-fed stream with stable flows and temperatures. Nutrient concentrations and spawning and rearing habitats also vary considerably among these streams. Scales were taken from adult rainbow trout from these streams and examined; they showed both widely-spaced outer, and narrowly-spaced inner, circulus zones. While there were no among-population differences in average circulus-spacing in the outer-growth zone, there were significant among-population differences in the inner zone; these two zones are suggested to represent (common) lake and natal stream rearing, respectively. The back-calculated minimum and average lengths at migration of juveniles from stream to lake was similar for all three populations (ca. 94 mm and ca. 140 mm, respectively) but there were significant among-population differences in age at emigration. The scale patterns and stream sampling suggested that most Hinemaiaia River rainbow trout left the river within the first year of growth (64%) whilst much higher proportions of juveniles surviving to adulthood in the other two streams overwintered before emigrating in their second year (up to 70%). Scales were also taken from juvenile rainbow trout captured from the Waimarino and Tokaanu Rivers. The patterns on these scales corresponded closely with the features seen on the inner-growth zone of the adult scales. This further strengthened the assertion that the inner-growth zone on the adult scales reflects a period of juvenile natal-stream growth before the fish go to Lake Taupo. The utilization of fluvial habitat by juvenile rainbow trout, common bullies and koaro in the Waimarino River was examined using minnow trapping as a methodology. There was segregation of habitat by these three species with regards to one or more of the following variables: 1) water depth, 2) water velocity, 3) substrate size, and 4) instream cover. Except in winter when the habitat choices by fingerlings (45-93 mm fork length) and smolts (>93 mm fork length) overlapped, there was also a segregation of habitat by the various size classes of juvenile trout, including fry (<45 mm fork length). Furthermore, there were ontogenetic trends and larger juvenile trout choose habitats with faster and deeper water and having substrates with larger diameters than did the smaller size classes of fish; larger juvenile trout were also more closely associated with instream cover. Woody and herbaceous cover were generally important for all species and size classes of fish in the Waimarino River. The distributions of juvenile trout and koaro and common bullies in the Waimarino, Tokaanu and Hinemaiaia Rivers was investigated. The species composition varied considerably among seasons, study sites and rivers. More bullies were found in the downstream reaches of these streams and this appeared to be positively related to water column depths and inversely related to velocities. There was a negative relationship between the catch rates of rainbow trout juveniles and koaro. The hydro-electric dam overflow channel on the Hinemaiaia River contained exceptional numbers of koaro. I also examined the inherited variability in parr mark numbers in juvenile rainbow trout from the Tokaanu and Waimarino Rivers. Ripe male and ovulated female trout were obtained from each of the study streams and reciprocal and pure crosses were made from the pooled gametes. The resulting juveniles were reared to fingerling size in separate tanks under similar conditions. The parr marks bisecting the lateral tine on the left side of the fish were counted and there were significant differences between the two pure crosses; the reciprocal hybrid crosses were intermediate in number. This suggests that there was a genetic difference controlling parr-mark number in these fish. The parr marks of wild-caught fingerling rainbow trout from the two study populations were also counted and there were no significant differences in number between these groups but the wild caught fish had intermediate numbers of parr marks compared to the laboratory fish. This suggests that either 1) there were genetic differences controlling parr-mark number between the laboratory and the wild fish with regards to the genetic control of parr mark number in these groups, or 2) population specific environmental influences (e.g., temperature) were modifying the parr-mark number of the genetically different wild juvenile trout, during their embryonic development in their respective natal streams, to produce a similar parr-mark number in these stocks of fish. Genetic differences in agonistic behaviour were also investigated in laboratory incubated juvenile rainbow trout from the Waimarino and Tokaanu Rivers. Because of the small sample sizes involved in this experiment, the results are considered to be only preliminary. However, if the observations reflect the behaviours in the wild populations, this genetic difference is likely to be adaptive and have evolved in response to the very different conditions in these two rearing streams. Finally, embryo and alevin development and survival rates were examined for fish from the Waimarino and Tokaanu Rivers. Two pure and two reciprocal-hybrid crosses were made and the resulting groups were incubated at the same time and under identical conditions at target temperatures of either 12 or 7°C. Within temperatures, the hatching date was the same for all crosses (12°C, 27 d; 7°C, 51 d). However, there were significant among-cross differences, within temperatures, with respect to emergence date; these differences were a result of phenotypic (egg size) and genotypic variability. Alevins from smaller eggs emerged earlier than equivalent crosses from larger eggs; alevins sired by Tokaanu River males emerged earlier than equivalent crosses of Waimarino River males. Samples of eggs were also taken ovulated rainbow trout from each population and the Tokaanu rainbow trout had lower egg weights at standard female lengths. These population differences in egg-size and rates of development are thought to be adaptive and to have evolved in response to conditions encountered by the incubating fish m their respective natal streams. The Tokaanu river has an inferior spawning environment, with lower intra-redd dissolved oxygen levels and poorer quality gravel; thus, selection has produced a population of rainbow trout having small eggs, fast developing alevins in order to maximize survival under adverse incubation conditions. Survival rates from fertilization to hatch in the experimental crosses were above 90% for all groups at both 7 and 12°C; however, embryos of larger eggs had slightly, but consistently, lower survival rates than embryos from smaller eggs, at both temperatures. Likewise, survival from hatch to emergence was also above 90% for all crosses at 12°C; however, there were substantial among cross differences in alevin survival rates at 7°C and this was the result of phenotypic (egg size) and genotypic (population) effects. These differences are also thought to be adaptive and appear to reflect selection resulting from water temperature differences that these alevins would normally encounter under natural conditions in their respective natal streams.
The immobilisation of Thermus strain Rt41A proteinase and its use in peptide synthesis
(The University of Waikato, 1991) Wilson, Shelley-Ann; Daniel, Roy M.; Peek, Keith
A proteinase isolated from Thermus strain Rt41A was purified to apparent homogeneity using ion exchange and FPLC chromatography and had a final specific activity of approximately 9000 azocasein units/mg. The substrate specificity of the proteinase against various peptide p-nitroanilide substrates was investigated and compared with the results of Peek (unpublished results) and Cowan et al. (1987b) Rt41A proteinase has a preference for aromatic amino acids in the P₁ site but, will also cleave the pNA group from peptides with leucine, arginine, alanine and lysine in this position. When utilising p-nitroanilide substrates the peptide must have a minimum of 3 amino acids for activity to be observed. Rt41A proteinase was immobilised to controlled pore glass (CPG) and Polymer Carrier Va-Epoxy Biosynth resin. The former of which was compared to the free proteinase. Both large (azocasein) and small (SucAAPFpNA) molecular weight substrates were utilised to measure the activity of the immobilised proteinase. Pore size of the CPG beads had little effect on % recovery of enzyme activity when it was added at a fixed level of activity/g of beads, whereas, it increased with increasing pore size when added at a fixed level/m² of support. Saturation of the CPG beads, with 105 nm pore size, was observed at 540 azocasein units/m². Lower levels (50 azocasein units/m² of 50 nm beads) were used in characterisation experiments. The specific activity of the immobilised proteinase was 5284 Au/mg with azocasein and 144 U/mg for SucAAPFpNA. The pH optimum of the immobilised Rt41A proteinase was 8.0 for azocasein and 9.5 for SucAAPFpNA compared to 10.5 for both substrates for the free enzyme. The immobilised enzyme retained approximately 65% of its maximum activity, against azocasein, at pH 12 whereas the free proteinase retained less than 10%. Stability towards pH increased on immobilisation, the greatest increase in half-life being approximately 12 fold at pH 7.0 at and 80 °C. Temperature activity profiles for both the free and immobilised enzymes were very similar when using either substrate. The stability of the immobilised proteinase however, was higher than that of the free enzyme in the presence and absence of CaCl₂ at various temperatures. Overall the results show that low levels of calcium (10 μM) protect against thermal denaturation, but that a high calcium concentration or immobilisation are required to protect against autolysis. Immobilisation of the proteinase also increased its stability towards two organic solvents, DMF and heptanol. Both the free and immobilised proteinase were utilised for peptide synthesis and the observed maximum yields were the same in both cases. A number of dipeptides were produced from amino acid esters and amides. The best acyl components, from those tested, were found to be Ac-Phe-OEt and Bz-Ala-OMe and Tyr-NH₂, Ala-NH₂, Trp-NH₂, Phe-NH₂, Leu-pNA and Val-pNA were all reactive nucleophiles. The substrate specificity for peptide synthesis was therefore very similar to that found for hydrolysis reactions. The synthesis of Bz-Ala-Tyr-NH2 was optimised by studying the effect of pH, temperature, solvent concentration, ionic strength and nucleophile and acyl donor concentration on the partition constant and the maximum yield. The initial conditions used were 25 mM Bz-Ala-OMe, 25 mM Tyr-NH₂, 70 °C, pH 8.0, and 10% v/v DMF. The optimised conditions were 80 mM Bz-Ala-OMe, 615 mM Tyr-NH₂, 40 °C, pH 10.0 and 90% v/v DMF; these conditions increased the maximum yield from 0.75% to 26% (% of original ester concentration). A number of cosolvents were also compared; the best peptide yields were observed with acetonitrile and ethyl acetate. Under optimised conditions acetonitrile gave similar yields (20%) as those observed in DMF except the acyl donor and nucleophile concentrations could be reduced to 25 mM and 100 mM respectively. The effect of different nucleophiles was also investigated with respect to peptide yield. Tyr- βNA and Tyr-pNA were found to be better nucleophiles than Tyr-NH₂. The yields observed were 48%, 61% and 8% respectively (90% v/v DMF, 40 °C, 25 mM Bz-Ala-OMe, 100 mM Tyr-X). No peptide was produced with Tyr-OBu as the nucleophile under the same conditions. With Ala in the P₁ position, and Tyr-pNA as the nucleophile, changing the blocking group or leaving group of the acyl donor had no effect on the peptide yield. Extending the length of the peptide of the acyl donor also had no effect. Peptide yields with Bz-Ala-OMe and Tyr-βNA in both DMF and acetonitrile was compared under optimised conditions. Quantitative yields were observed in DMF whereas only 26% yield was found in acetonitrile. Therefore acetonitrile, compared to DMF, increased peptide yields with the Tyr-NH₂ nucleophile, decreased yields with the Tyr-βNA nucleophile and it was also shown to have no affect on yields with the Tyr-pNA nucleophile.
A conceptual and psychometric examination of climate anxiety
(The University of Waikato, 2026) Gago, Tomás; Sargisson, Rebecca J.; Milfont, Taciano L.
Climate change stands as one of the most pressing crises threatening the world today, affecting natural environments, community resources and functioning, and individual’s health. As this crisis worsens, people are increasingly reporting experiencing negative affective reactions to climate change, even when they have not themselves been directly impacted by it. These various reactions, described under the umbrella term of “climate anxiety”, have been the focus of numerous studies, but the lack of a consistent definition and theory of climate anxiety has hindered scholars’ ability to integrate and build on the knowledge gained from these studies. My aim with this thesis is to contribute to this integration effort by articulating the various contributions from other scholars into a cohesive and holistic conceptualization of climate anxiety, and to examine how prevalent and adaptive this phenomenon is. Thus, the first study in my thesis (Chapter 3) is a metaanalysis of 25 studies examining the link between climate anxiety and psychological wellbeing. In this study, we found there was a strong association between these variables, whereby higher levels of climate anxiety were associated with lower levels of wellbeing. Given the consistent association between climate anxiety and psychological illbeing, in the next study (Chapter 4), we found that measures of climate anxiety capture this phenomenon differently to how measures of domain-free psychopathology capture their respective target constructs, by focusing more on affective reactions and less on somatic complaints. Additionally, we also found evidence supporting the convergence of the different climate anxiety measures, indicating they could be capturing the same underlying trait, and raising questions about the lack of parsimony in climate anxiety measuring. To address these concerns, in Chapter 5, we report a mixed-methods study where we developed a condensed climate anxiety measure with a wider representation of the various features associated with climate anxiety using Rasch modelling. Despite its wider content representation and ability to differentiate between high levels of climate anxiety, our measure did not predict wellbeing outcomes better than an existing eco-anxiety measure. Therefore, for the next study (Chapter 6), we used an established measure of climate anxiety to assess the prevalence of climate anxiety in New Zealand, finding that 1 in 20 New Zealanders report experiencing these affective reactions. Furthermore, we found that people who have been directly impacted by climate change, people with environment-dependent jobs, and those who did not feel prepared to handle climate change reported higher levels of climate anxiety. Lastly, we found that those with higher levels of climate anxiety also reported higher psychological distress and more engagement in pro-environmental behaviours. Altogether, this thesis contributes to the climate anxiety literature by providing a framework for the assessment of the various dimensions of climate anxiety and how they may be contributing to individual and planetary wellbeing. Moreover, the findings here may be used to raise awareness for the potential benefits and impairment associated with climate anxiety, and justify support for groups at increased risk of maladaptive climate anxiety.
Media, diaspora, and political engagement: Exploring the role of ethnic Chinese media in shaping Chinese New Zealanders' political participation in Aotearoa
(The University of Waikato, 2026) Zheng, Jiancheng; Hardy, Ann; Galikowski , Maria
This study investigates the intersection of Chinese-language media, 2020 New Zealand general election, and the lived experiences of the Chinese diaspora within New Zealand's dual bicultural and multicultural frameworks. As New Zealand's demographic composition grows more diverse, Chinese-language media have become vital in supporting cultural continuity and promoting political involvement within the Chinese community. This research emphasizes the distinctive role of the ethnic media—especially platforms like WeChat—in influencing the political behaviour, identity formation, and community dynamics of Chinese New Zealanders. Through the mixed research methods of the 2020 New Zealand general election, the study explores how the ethnic media shape voting patterns and political preferences, bridging critical language and access gaps for a community often sidelined within mainstream political discourse. Moreover, the study addresses the specific challenges faced by Chinese-language media, including financial constraints and censorship, and examines the broader impacts of information accessibility and media quality on democratic participation. The findings deepen the understanding of the Chinese diaspora's shifting role within New Zealand’s political landscape, reflecting wider global trends in diaspora media and minority political engagement. By positioning the experiences of Chinese New Zealanders within New Zealand's bicultural commitments and its multicultural realities, this research offers nuanced insights into the integration of the ethnic media in supporting a society's democratic infrastructure.
The interplay of the entrepreneurship ecosystem, collective entrepreneurship, and civic wealth creation in the tourism and agricultural sectors: A Sri Lankan perspective
(The University of Waikato, 2026) Gajanayaka, Channa; Pavlovich, Kathryn; Sinha, Paresha N.
Entrepreneurship research frequently treats entrepreneurship ecosystems, collective entrepreneurship, and civic wealth creation as parallel or pairwise explanations, leaving limited understanding of how these domains interact, generate reinforcing (or weakening) feedback, and co-evolve over time, particularly in emerging-economy contexts where institutional coordination is uneven and entrepreneurial practice is routinely shaped by shocks and livelihood insecurity. This thesis addresses that gap by developing the Triadic Synergy Model (TSM), an original, mechanism-based analytical lens that specifies reciprocal influence and feedback among Entrepreneurship Ecosystems (EE), Collective Entrepreneurship (CE), and Civic Wealth Creation (CWC), while conceptualizing Individualistic Entrepreneurship (IE) as a cross-cutting constraining practice logic that dampens triadic coupling. Empirically, the study adopts a qualitative multiple-case design focused on Sri Lanka’s tourism and agricultural sectors, drawing on semi-structured interviews with SME entrepreneurs, conducted primarily in participants’ mother tongue, with follow-up interviews and iterative thematic analysis and cross-case comparison to identify mechanisms, boundary conditions, and sectoral patterning. Findings show that CE is not a generic claim of “working together” but an achieved coordination capability: synergy emerges when participation is sustained and governance is credible. Under these conditions, CE enhances EE functioning by translating ecosystem supports into usable capacity (e.g., shared infrastructures, pooled learning routines, and collective voice) and can catalyze civic endowments when collective enterprise is organized around inclusion, stakeholder participation, and community capability building. EE is experienced less as a static set of “elements” than as workable access points (e.g., regulatory and procedural infrastructure, skills, finance, market channels, and shared resource pools) that condition day-to-day continuity and shape whether collective arrangements and civic pathways can persist. CWC is evidenced as multidimensional endowment creation and, in necessity-driven settings, as a survival and resilience pathway; however, civic wealth durability depends on participation infrastructures and credible support regimes rather than enterprise goodwill alone. Across the triad, boundary conditions are systematic: low trust, role ambiguity, opportunism concerns, politicization, and survival-first constraints weaken CE and narrow civic outcomes, interrupting the reinforcing loops the TSM specifies. By sector, tourism exhibits more consistent triadic reinforcement due to higher interdependence and more visible participation infrastructures, whereas agriculture shows stronger IE resistance, coordination fragility, and weaker feedback channels, yielding more constrained and discontinuous reinforcing pathways. By integrating Active Influence and Reactive Adaptation logics, the thesis advances a contingent, governance-sensitive explanation of when ecosystem supports translates into durable collective capability and when entrepreneurial activity produces civic wealth that consolidates over time in emerging-economy sectors.
Synthesis and kinetics of isomerisation of 2',6'-dihydroxychalcones
(The University of Waikato, 1987) Miles, Christopher O.; Main, Lyndsay
The first-order rate constant, kₒbₛ, for the chalcone - flavanone isomerisation has been determined over the pH range 0-14 in water (μ = 1.0 mol 1⁻¹ with KC1) at 30°C for the following 2' ,6'-dihydroxychalcones: 2' ,6'-dihydroxychalcone (34); 2' ,6'-dihydroxy-4-methoxychalcone (38); 2' ,6'-dihydroxy-3,4-dimethoxychalcone (40); 2' ,6'-dihydroxy-3,4,5-trimethoxychalcone (42); 2' ,6'-dihydroxy-2,4,6-trimethoxychalcone (44); 4-chloro-2' ,6'-dihydroxychalcone (46); 2' ,6'-dihydroxy- 4,4'-dimethoxychalcone (32); 2' ,6'-dihydroxy-3,4,4'-trimethoxychalcone (36); and 2' ,4,6'-trihydroxy-4'-rhamnoglucosyloxychalcone (naringin-chalcone) (48). The pH-rate profiles have been analysed in terms of contributions to cyclisation and ring opening of the various ionised chalcone and flavanone species, and individual rate and equilibrium constants for all the contributing reactions have been determined. Rate measurements with D₂O as the solvent (for 32, 34, 36, 38, 40, 42, 44, 46) revealed a large (presumably primary) hydrogen kinetic isotope effect for one of the contributing reactions, the cyclisation of the chalcone mono-anion. Enthalpies and entropies of activation for the mono-anion cyclisation have also been determined for chalcones 34, 36, 38, 42, 44, and 46. ¹H n.m.r. studies of the product from the cyclisation of the mono-anion in D₂O for two chalcones (34, 38) showed little preference in protonation at the 3-position of the flavanone. Mass spectrometry allowed measurement of the preference for protonation over deuteriation at the 3-position of the flavanone during cyclisation of the mono-anions of 32 and 38, under kinetically-controlled conditions in H₂O - D₂O mixtures. The data obtained were not in accord with the those from kinetic isotope effect measurements. The above results were considered in terms of possible mechanisms for the various reactions involved in the isomerisation. Factors contributing to the specially high rate of cyclisation of 2' ,6'-dihydroxychalcones as compared to simple 2'-hydroxychalcones, and to the high stability of the 5-hydroxyflavanones as compared to simple flavanones (relative to their isomeric chalcones) were also considered. The low stability of the 2' ,6'-dihydroxychalcones, compared to the 2'-hydroxychalcones (relative to their flavanones) was found to be due to a highly reactive mono-anion form combined with a lower first pKₐ, and a greatly reduced susceptibility of the flavanone anions to base-catalysed ring opening. By utilising the above kinetic results, new and improved syntheses of 2' ,6'-dihydroxychalcones have been developed in the face of what are shown to be unreliable literature reports. The following compounds have been synthesised and characterised for the first time: (32); (34); (36); (38); 5-hydroxy-4' -methoxyflavanone (39); (40); 5-hydroxy-3' ,4'-dimethoxyflavanone (41); (42); 5-hydroxy-3' ,4' ,5'-trimethoxyflavanone (43); (44); 5-hydroxy-2' ,4' ,6'-trimethoxyflavanone (45); (46); 5-hydroxy-4'-chloroflavanone (47): 6-benzyl-7-benzyloxy-5-hydroxyflavanone (68); 6-benzyl-5,7-dihydroxyflavanone (69); 2 '-hydroxy-6 '-tetrahydropyrany loxy-3, 4, 5-trimethoxychalcone (70); 3'-benzyl-4' ,6'-dibenzyloxy-2'-hydroxychalcone (72); 2' ,3,4' ,6'-tetrahydroxy- 4-methoxychalcone (86); 2'-hydroxy-4' ,6'-dimethoxy-3'-methylchalcone (93). Two new routes to 2' ,6'-dihydroxychalcones were developed. The first involved base-catalysed condensation of acetophenones and benzaldehydes with free phenolic groups protected as their tetrahydro-pyranyl ethers, followed by deprotection at pH 2. The second involved reaction of flavanones with chlorosilanes, in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, in which ring opening of the O-silylated flavanone was immediately followed by silylation of the resultant phenolate oxygen, thereby preventing recyclisation. The crystal structures of 5-hydroxy-4' ,7-dimethoxyflavanone (33) and 2' ,6'-dihydroxy-2,4,6-trimethoxychalcone (44) were determined by X-ray crystallography, 44 being the first 2' ,6'-dihydroxychalcone for which a crystal structure has been obtained. A computer programme was developed for the analysis of pH-rate data for 2'-hydroxy- and 2', 6'-dihydroxy-chalcones, but which is suitable for the analysis of pH-rate data for most mono- or di-acids in which the contributing reactions are (pseudo) first-order. The programme can also include second-order H⁺-catalysed reaction of the di-acid, and one second-order OH⁻-catalysed reaction, and calculates the concentrations of the various ionised species present on the basis that the two pKₐ values may not be well-separated. This programme has been used to successfully analyse the 2' ,4'-dihydroxychalcone - 7-hydroxyflavanone pH-rate profile previously reported, but not analysed, in the same way as for the 2' ,6'-dihydroxychalcones.

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