14,551 results for Doctoral

  • Studies in Marine Natural Product Synthesis, Isolation and Ecology

    Lindsay, Brent Steven (1998)

    Doctoral thesis
    The University of Auckland Library

    Previous studies indicated the marine pyridoacridone alkaloid ascididemin possessed a unique biological profile. Investigation of synthetic routes to ascididemin led to the discovery that ascididemin precursors possessed a wide range of biological activities. One precursor possessed hollow fiber in vivo antitumoral activity and continuing in vivo studies at the NCI, using subcutaneous xenograft assays, are in progress. A crystal structure of a precursor indicates that these tetracyclic heterocycles are planar, suggesting intercalation as a mechanism of antitumoral action. Ascididemin was synthesized by two novel ring E forming reactions. The superior methodology was also useful in the preparation of analogues, such as kuanoniamine A. Ascididemin possessed promising hollow fiber in vivo antitumoral activity but was poorly active in a subcutaneous xenograft study. Ascididemin was incapable of exerting antitumoral activity at a distance and further analogues were prepared to address this problem. Ten analogues were prepared, with all the non-bromine containing analogues selected for in vivo evaluation at the NCI. Two ring A analogues were prepared by a thennew synthetic route, including the antiviral natural product 11-hydroxyascididemin. 11-Methoxyascididemin was selected for hollow fiber evaluation. Two bromine containing ring D analogues were prepared, including the antifungal natural product 2-bromoleptoclinidinone. A crystal structure on 2-bromoleptoclinidinone was the first determined on a pyridoacridone alkaloid and the molecule was planar, further supporting an intercalative mechanism of action. Due to non-selective antitumoral cytotoxicity, ring D analogues are not useful antitumoral agents. Six carbon-based ring E analogues were prepared by novel methodology. All 6-substituted analogues assessed were selected for in vivo antitumoral evaluation. Hollow fiber antitumoral activity decreased with bulk of the substituent. 6-Methylascididemin has been selected for subcutaneous xenograft studies. The 5-substituted analogue prepared gave the best in vitro antitumoral profile of all alkaloids in this study and has been selected for in vivo evaluation. Ring E substituted N-8-deaza-ascididemin analogues possessed no antitumoral activity, highlighting the importance of the 1,10-phenanthroline-like bay region of ascididemin in antitumoral activity. Another four structurally novel, quinoid containing alkaloids have been selected tor in vivo evaluation. While ascididemin was the only compound capable of topoisomerase IIα cleavable complex stabilization, related alkaloids possessed a similar level of inhibitory action against this enzyme. This further supports intercalation as the dominant mechanism of action for pyridoacridone alkaloids. Ecological roles of four natural pyridoacridone alkaloids were assessed. Alkaloids were species specific antifeedant agents against important consumers. These alkaloids may have a long term detrimental effect on predator physiology, due to the well established ability of these alkaloids to interfere with cell proliferation. Ascididemin elicited avoidance responses in numerous marine species. Ascididemin has no antifouling activity against macrofoulers. Microbiological assessment of ascididemin, 11-hydroxyascididemin and 2-bromoleptoclinidinone indicated that modification of the ascididemin chromophore leads to the directing of antimicrobial activity towards a different phyla of parasites. Pyridoacridone alkaloids may be part of a non-antibody based immune system. All studies point to pyridoacridone alkaloids enhancing the eventual reproductive success of the organism. Biological and chemical evaluation of 29 New Zealand ascidians has been performed. Significant biological activity was detected in ten ascidians. Novel metabolites isolated were 2-(3'-bromo-4'-hydroxyphenol)ethanamine (Cnemidocarpa bicomuta) and 1,3-dimethylguanine (unidentified ascidian). Known metabolites isolated were 1,3-dimethylisoguanine (Cnemidocarpa bicomuta) and rubrolides A, B and C (unidentified ascidian). The survey highlighted the importance of overexpressed purine bases in ascidian metabolism. No physiological roles for these overexpressed purines are as yet apparent. Our study of NZ ascidians has led to the isolation of many compounds previously isolated from sponges. The widespread distribution of such metabolites gives credence to the theory that common metabolite-generating genes are present in both phyla, due to the evolutionary success of these genes. Two optically active 9-(5-S-methyl-5-sulfinyl-lyxofuranosyl)-9H-purin-6-amine (lyxosyl-MTAS) nucleosides were isolated from the nudibranch Doriopsis flabellifera. This is the first report of any lyxosyl-MTAS nucleoside as either a natural or synthetic product.

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  • The retention of picoplankton by the pacific oyster, Crassostrea gigas, and implications for oyster culture

    Bell, Andrew Harwood (2006)

    Doctoral thesis
    The University of Auckland Library

    Pacific oyster (Crassostrea gigas) farming in New Zealand has reached a point where the pressures on resources appear likely to constrain current, and future, development. To maintain industry growth, security of juvenile oyster (spat) supply and productivity gains within the existing farm leases, are becoming industry imperatives. The use of hatchery technology could achieve both of these requirements, but it is expensive to establish and maintain. The additional expense of a hatchery could be offset by the establishment of, for example, a selective breeding program to enhance oyster productivity and/or marketability. Consequently a pilot-scale oyster hatchery facility was constructed to investigate the potential for establishing hatchery production of Pacific oysters in New Zealand. This study showed that in the pilot-scale hatchery, oysters could be successfully spawned from in-season broodstock, the eggs fertilised and the resultant larvae reared through to settlement for on-growing to adult size. This process was successful for both oysters selected for morphological characteristics and those which were not. On-growing of the resultant stock indicated growth rate could be normal relative to wild caught oysters spat, although data was limited by the small scale of the experiment. However, an investigation of broodstock conditioning, to achieve out-of-season spawning, was less successful. Disease occurred and condition was lost in some broodstock, suggesting they were enduring stress within the conditioning system. The microalgal food supply was examined but the clearance rate of the microalgal species suggested they were an acceptable feed supply which agreed with previous reports of successful conditioning techniques. Comparing the pilot-scale facility in this study with descriptions of facilities which reported successful broodstock conditioning suggested that the use of a microfiltered recirculating water supply, as opposed to the more common flow-through, natural seawater systems containing a range of small size particles, limited necessary nutrient and/or maturation factors and may have had a significant impact on conditioning. The nanoplanktonic (< 10 μm), food resource, which includes key microalgal species such as Chaetoceros spp. and Isochrysis spp., is generally considered the primary food resource for suspension feeding bivalves, including C. gigas. However, the picoplanktonic fraction (< 3 μm) can provide the largest proportion of this food resource in the water column in terms of abundance and biomass. Consequently, an investigation of the in situ retention of picoplankton populations (picoeukaryotes, Synechococcus-type cyanobacteria and heterotrophic bacteria) by oysters was undertaken. Flow cytometry was used to quantify the picoplankton populations in water samples taken from the inhalant and exhalant feeding currents of individual oysters, allowing retention efficiency of the particles to be calculated. Five picoplankton populations were identifiable by flow cytometry (picoeukaryotes, heterotrophic bacteria and 3 populations tentatively identified as cyanobacteria) and accounted for a large proportion (up to 97 %) of the estimated available carbon (picoplankton + microalgae) in Kerikeri Inlet water. Generally the heterotrophic bacteria accounted for the largest proportion of the biomass with up to 564 ± 51 ng C ml-1. Retention of each picoplankton population was found to be variable and not directly related to particle concentration. Cyanobacteria (Cy2 population) were retained with the greatest efficiency (up to 42 ± 4.4 %), followed by heterotrophic bacteria (up to 38 ± 4.5 %) and picoeukaryotes (up to 12 ± 3.8 %). Overall more picoplankton biomass was retained during the summer months, of which the heterotrophic bacteria made the largest contribution in either cell number or estimated carbon retained. Tracking of the condition and constituent fractions (glycogen, lipid and protein) of the subject oysters showed that in the summer months, post-spawn, these levels were lowest, indicting a period of nutritional stress. This appeared to suggest that C. gigas was able to alter its retention efficiency to expand the range of particles captured, and consequently the available nutrient pool. The retention of greater quantities of heterotrophic bacteria may allow for the acquisition of essential nutrients required for growth and later gametogenesis (such as B vitamins). However, it is also possible that the heterotrophic bacteria mediate access to otherwise inaccessible, or inefficiently accessed, nutrient resources through their degradation of, for example, crystalline cellulose. Consequently, the microbial flora associated with the oyster gut was investigated. An initial investigation, cultivating bacteria from gut contents, showed considerable variability in the numbers of colonies present within and between samples, but was inconclusive for identifying differences in species diversity. Using culture independent histological and 16S rDNA PCR/RFLP techniques to investigate the oyster gut microflora a spirochaete flora, commonly associated with bivalve crystalline styles, was clearly present. Molecular analyses provided evidence of other bacterial in the gut. A signature RFLP band pattern was found in oysters at low tide and this generally reoccurred in oysters that had been immersed for varying lengths of time up to high tide. However, the signature RFLP pattern became more dilute as immersion time/potential feeding time extended. The isolation of culturable bacteria from the oyster gut allowed characterisation and identification of a subset of the oyster gut microflora. 16S rDNA sequence analysis from selected isolates showed a predominance of Vibrio spp. These bacteria had previously been associated with marine molluscs, including as symbionts. Characterisation of these and other isolates from oyster gut showed a diversity of attributes including the ability to degrade cellulose. This suggests the bacterial production of enzymes, such as cellulases, which have been reported by other researchers as being present in ineffectual or low native levels in oysters. Consequently the bacterial presence in the oyster gut may be essential to efficient nutrient acquisition. The results of these investigations have highlighted the potential importance of the heterotrophic bacteria to C. gigas. To date, bacteria have received relatively little attention in terms of their potential nutritive contribution to oysters, primarily due to observations that they are retained with low efficiency. However, even at low retention efficiencies the potential nutritive contribution is large due to the available abundances of heterotrophic bacteria. While the mechanisms and controls of bivalve suspension feeding have yet to be fully elucidated, the published literature indicates that selective mechanisms are available to bivalves including C. gigas and this current research suggests that even pico-sized particles, retained with apparently low efficiency, can be subject to selection. The importance of the heterotrophic bacteria to C. gigas requires further investigation as it will have implications for not only hatchery production, but also farm management, public health and environmental impact monitoring.

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  • Trade Policy, Processing, and New Zealand Forestry

    Gilbert, John (1998)

    Doctoral thesis
    The University of Auckland Library

    The New Zealand forestry sector is well recognised as being amongst the oldest and most historically, politically, and economically significant sectors in this country's European history. In recent years, in particular those following the major restructuring of the industry which took place in the latter half of the 1980s, the forestry industry has come under increasing scrutiny for its potential as a major source of export revenue for New Zealand, as supplies have begun to vastly outstrip demand. The sector is also a significant employer, and contributor to national income. Moreover, it is an industry which has come to embody the current New Zealand debate on foreign ownership, environmental concerns, and in particular, the costs and benefits of encouraging the domestic processing of New Zealand's resources. However, despite its substantial importance to the New Zealand economy, surprisingly little extensive research has been undertaken on the forestry sector. This is particularly so with respect to trade policy aspects. It is a well accepted fact that there has been an imbalance of effort within New Zealand which has led to numerous models of the forest resource and limited attention to the market, and in particular models of the small open economy and international trade. This study partially corrects this imbalance. It identifies and examines three core issues with respect to the issue of log export restrictions; the impact on processing and welfare; the effect of foreign ownership of the resource in respect of the income transfers which result from processing incentives: and the possibility of utilising export restrictions as a retaliatory strategy against escalating tariff structures. It also examines the impact of liberalisation of forestry products trade on a region-wide basis. The methodology employed in this study is a combination of formal economic modelling, and counterfactual simulation using computable general equilibrium (CGE) modelling techniques. We make use of both our own purpose-built single country model, and the existing GTAP model in our simulations. The study makes a contribution to the existing literature by incorporating foreign ownership into a formal analysis of processing incentives, developing a new CGE model of the New Zealand economy which incorporates econometric estimates of key relational parameters, utilising this model to evaluate the costs of export restrictions - which are shown to be substantial, and utilising the GTAP to provide insights into the possible effect of the APEC Early Voluntary Sector Liberalisation strategy - where we find evidence to suggest that MFN liberalisation by APEC members may lower group welfare.

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  • Novel Interferometric Techniques in Profilometry and Spectrometry

    Helg, Tina Louise (2000)

    Doctoral thesis
    The University of Auckland Library

    The work in this thesis is in the fields of profilometry and Fourier transform spectrometry. Deformation measurement of diffuse objects by phase stepping was achieved by thermal frequency drift in a HeNe laser. The system was easy to construct, required no specialised components, was immune to the effects of piezo-actuator hysteresis, and was capable of producing phase maps in which noise was less than 1/20λ. A method was proposed for measuring absolute surface profile by scanning frequency over the range of a white light source. The coincidence technique of coherence radar was used to measure surface profiles in three dimensions to micron accuracy. Spatial techniques were developed to process the large data set quickly and efficiently. A novel Fourier transform spectrometer was developed to measure the spectrum of narrowband light sources. Heterodyning techniques gave a resolution of 0.01nm with a free spectral range of =2.5nm. The Sagnac common path design afforded immunity to vibration. The mode structure and mode hopping characteristics of a typical laser diode were measured as a function of diode injection current. An improved Fourier transform spectrometer was developed. Based on a Michelson interferometer. The instrument could resolve to 0.013nm over a =3nm free spectral range. Instrument operation was simplified and functionality was extended to non point sources.

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  • Personal Constructs of Organisational Identity and Identification Following Education Reform in the New Zealand Polytechnic Sector

    Conroy, Denise M. (2002)

    Doctoral thesis
    The University of Auckland Library

    Organisations face massive changes as they adapt to mergers, takeovers, downsizing or simply adding .com to their name, and all of these changes challenge the organisation's identity. Despite this understanding, little research has been done in the area of how employees react to a change in their organisation's identity, and how such a change may impact upon their own identification. The New Zealand environment represented a unique opportunity to address this gap in the literature. Local expressions of worldwide economic reform have been swift and extensive, with the commercialisation of the tertiary sector presenting a rare opportunity for exploring how change impacts upon the organisation's identity and employees' identification. From this base, the following research question was developed: How do polytechnic tutors interpret the changes to their organisation's identity and their own identification, following education reform in the New Zealand polytechnic sector? A constructivist approach was used" utilising three means of inquiry. Firstly, three separate institutes were selected, with the business school being the site of inquiry for each Case. At each site, repertory grid interviews with long-term employees were conducted to generate data at the level of the individual, and at the level of the organisation. And finally, semi-structured interviews were undertaken with senior management to provide background information on strategic direction and vision. A content analysis of both the repertory grid interviews and the semi-structured interviews provided a rigorous process of analysis. Results from this research make several contributions to our knowledge of identity and identification. The data revealed that the organisation's identity consists of a plurality of identities, with one overarching Meta Identity. Whilst other aspects of identity may change to adapt to the demands of the external environment, the Meta Identity is far more resilient, or 'sticky.' In addition to revealing the hierarchical nature of organisational identity, the data also demonstrate evidence of two paths for employees 'becoming' identified, specifically emulation and affiliation. The findings also indicate that whilst change may not create a reduction in the strength of identification, it may create a change in the need it is serving for the employee. Such changes can be detrimental to both the employee and the organisation.

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  • A Mathematical Study of Calcium Oscillations and Waves

    Tsaneva-Atanasova, Krasimira Todorova (2004)

    Doctoral thesis
    The University of Auckland Library

    In this thesis we study theoretically the dynamics of the free cytosolic Ca2+ concentration. We construct a mathematical model of the Ca2+ dynamics in pancreatic acinar cells. Although this model refers to a particular cell type, it also allows us to study some aspects of Ca2+ signalling in general. We begin by analysing the dependence of the Ca2+ oscillations on the plasma membrane transport. Further we study the propagation of intercellular Ca2+ waves in a pancreatic acinus. It has been observed experimentally that, in many cell types, calcium fluxes across the plasma membrane affect inositol trisphosphate IP3-induced calcium oscillations. Since IP3-induced calcium oscillations involve the cycling of calcium to and from the endoplasmic reticulum, it is not well understood how they can be so strongly affected by membrane fluxes. We use a mathematical model to answer this question; a model that relies on the introduction of a slow variable, the Ca2+ load of the cell. Our model predictions are confirmed by experimental results. Since similar behaviour is observed in two other models of IP3-induced Ca2+ oscillations, it is possible that this bifurcation structure is a generic feature of Ca2+ oscillation models. The effect of intercellular coupling on the oscillatory dynamics is investigated theoretically. It is demonstrated that junctional calcium diffusion can account for the co-ordination and synchronisation of cytosolic calcium oscillations in a coupled triplet of cells under the assumption of constant IP3 concentration in each individual cell. Furthermore a two dimensional version of that model, where Ca2+ and IP3 are assumed to diffuse within as well as between the cells, has been studied numerically. Compared to the results from the analysis of the ODE model, the results from the analysis of the PDE model (in two spatial dimensions) reveal some interesting spatial effects of the diffusion, and of the geometry of the cells on the collective oscillatory behaviour of the systen. Based on this combined approach, a suggestion about the specific role of both Ca2+ and IP3 in the intercellular Ca2+ signalling has been made.

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  • Organosilanes: Synthesis and Reactivity Directed Towards Annulations

    Harris, Paul William Richard (2000)

    Doctoral thesis
    The University of Auckland Library

    Ruthenium-catalysed coupling of alkenes (principally vinylsilanes) with the ortho C-H bond of a wide range of monocyclic, bicyclic and tricyclic aromatic ketones led to a high yield of ortho-alkylated adducts. A methoxy substituent located para to the directing carbonyl moiety had an activating effect while an ortho methoxy resulted in severe inhibition of the coupling reaction and methoxy cleavage was observed. However, an ortho TBDMS ether allowed the C-H/olefin coupling to proceed quantitatively, which was attributed to inhibition of catalyst quenching by preventing chelate formation. With a view to cyclopentaannulation, the adducts from the C-H/olefin coupling containing a ArCH2CH2SiMe3 side chain were functionalised by radical bromination leading to a 1,2-dibromo compound which was converted into a COCH3 by elimination and hydrolysis. An analogous sequence, when applied to a more complex substrate, gave products resulting from bromination and/or elimination at a different benzylic site. Attempted intramolecular aldol reactions of a 1,4-dicarbonyl compound failed and resulted instead in skeletal rearrangement. The carbon-silicon bond in ArCH2CH2SiMe3 could be converted into a silanol (RSiMe2OH) when treated with aluminium chloride, but attempts to oxidise the C-Si bond (to give an alcohol) in this compound were unsuccessful. Silicon-carbon bond oxidation in adducts containing a ArCH2CH2Si(OR)xMey side chain gave an ArCH2CH2OH fragment provided that a proximal ketone was converted to an alcohol prior to the oxidation to avoid unwanted Baeyer-Villiger reaction. The resultant 1,5-diols could not be oxidised directly to a 1,5-dicarbonyl compound, but were converted into a mono alcohol by ionic hydrogenation and subsequent deprotection in excellent overall yield. Successive benzylic and primary alcohol oxidation provided the required 1,5-dicarbonyl functionality, but this enone aldehyde was not suitable for cyclopentaannulation. Attempts to synthesise an alternative substrate (a keto aldehyde) via protection of the primary alcohol followed by benzylic oxidation were unsuccessful, but could be achieved by conjugate reduction of the enone. The ensuing pinacol coupling failed. The quassinoid ring system was accessed by functional group interconversion to yield a δ-keto ester, which underwent latonisation using SmI2. Coupling of alkynylsilanes with the ortho C-H bond of various aromatic ketones proceeded in high yield under ruthenium catalysis and resulted in the introduction of a vinyl group predominantly of E configuration. In contrast, the aromatic ketone 1-acetylnaphthalene, underwent cyclopentaannulation in a one-pot sequence under analogous conditions, which was confirmed by X-ray crystallographic analysis. This was proposed to occur via β-silyl migration as a key step. Attempts to synthesise an alkynylsilane bearing alkoxy substituents failed and gave only a dialkyne, which underwent ruthenium-mediated C-H bond insertion cleanly. The resultant alkenylalkynylsilanes could not be oxidised to an aldehyde. Trimethyl orthoformate-promoted intramolecular cyclisation of the ortho vinylated aromatic ketones resulted in cyclopentaannulation in high yield. The newly formed 5-membered ring was confirmed by an X-ray structure of a diterpenoid analogue. Mono or tricyclic substrates produced benzofulvenes in high yield when the ketone was exocyclic, while a naphthalene derivative resulted in the isolation of methanol adducts. A diterpenoid containing a dihydrofuranyl ring could be synthesised via intramolecular Hg(II) cyclisation of an alcohol and a proximal alkene.

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  • Nonmetrisable Manifolds

    Greenwood, Sina Ruth (1999)

    Doctoral thesis
    The University of Auckland Library

    Nyikos has defined a tree, denoted T, associated with any given Type I space. This thesis examines the properties of an T-tree if the space is a Type I nonmetrisable manifold. It is shown that a tree, T, is an T-tree of a Type I manifold iff T is a well-pruned ω1-tree. Furthermore, if T is any well-pruned ω1-tree, there are 2N1 different Type I manifolds for which T is the T-tree. The relationships between the properties of a Type I manifold and the properties of its T-tree are examined. It is shown that whenever a Type I manifold contains a copy of ω1, its T-tree must contain an uncountable branch. The thesis then addresses the problem of whether or not an arbitrary tree T admits a Type I manifold which is ω1-compact. If T does not contain an uncountable antichain, or a Suslin subtree, then there exists a Type I manifold with T-tree T. If T contains an uncountable antichain, then whether there exists an ω1-compact Type I manifold with T-tree T is undecidable. (*) implies there does not exist such a tree while ◊ implies that there does. If we assume ♣+, then at least one such manifold exists. ◊ also implies that if T contains a Suslin subtree, then there exists an ω1-compact manifold with T-tree T. Nyikos has recently defined a Type II space. We may associate an T-tree with such a space. This thesis shows that a Tree, T, admits a Type II manifold iff T has height not greater than ω1, and each level has cardinality no greater than c. The final chapter examines the relationship between microbundles and fibre bundles over nonmetrisable manifolds. In 1964 Milnor defined the notion of a microbunble. He ceased developing the theory of microbundles when later in the same year Kister showed that a microbundle over a metrisable manifold is equivalent to a fibre bundle. This thesis proves that the tangent microbundle over a manifold is a fibre bundle iff the manifold is metrisable. As a consequence of this we obtain further properties equivalent to metrisability in a manifold.

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  • Johann Jacob Bodmer, Interculturalist Cultural Realignment in the 18th Century and the Role of a Zurich Translator

    Baumer, Helen (2004)

    Doctoral thesis
    The University of Auckland Library

    Johann Jacob Bodmer stands at the beginning of a new era that saw the establishment of major English literary influences in Germany along with the rise of English to become a language of importance of the European stage. The particular importance of this eighteenth-century Zurich translator and literary scholar lies in his translation of a canonical work of English literature, Paradise Lost, and in his tireless efforts to develop appreciation of this work in the German debate on aesthetics and translation of the 1730s. Bodmer was strongly opposed by scholars wishing to establish in Germany the neoclassical aesthetic conventions prevailing in France, then the hegemonic power in Europe. By overcoming the advocates of French literary models he paved the way for the widescale translation of English authors such as Shakespeare, and the adoption of English models. As a translator, Bodmer advocated norms of faithful translation that deviated from those advanced for Germany by the advocates of French literary models. This study explores the origin of the new Zurich ideas, and outlines the extensive debate on translation conducted in Germany in the 1730s, in which Bodmer and his colleague Johann Jacob Breitinger overturned the arguments of Johann Christoph Gottsched and his supporters. In a number of respects, Bodmer and Breitinger's ideas on translation can be seen as precursors of the 'foreignising' approach to translation developed by German thinkers such as Friedrich Schleiermacher at the end of the eighteenth century. My study also investigates Bodmer's translation practice in detail, based on analyses of his German translations of Paradise Lost. It gives particular attention to the way in which the debates of the 1730s prompted changes in his thinking on translation. Of especial interest here are his ideas on the translation of metaphor, to which he appears to have devoted more attention than any thinker before him. My study applies a new approach to studying translation history currently being developed by translation scholar Anthony Pym. Pym's 'professional interculture' ideas focus particular attention on individual translators and groups of translators, and the importance of their debates and discussions for negotiating translation norms.

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  • The structure of Karam: a grammar of a New Guinea Highlands language

    Pawley, Andrew (1966)

    Doctoral thesis
    The University of Auckland Library

    Karam is spoken in the Bismarck-Schrader Ranges on the northern border of the Western Highlands District of Australian New Guinea. Karam speakers, numbering some 10,000 to 14,000, occupy several valleys both on the Ramu and the Jimi falls of these ranges. On the Ramu fall they occuPY the AiomeRamu slopes, the Asai Valley, and the Upper Simbai Valley as far east as Songuvak on the northern side and Tembiamp on the southern side. On the Jimi fall they occupy the Aunjang and Kaiment Valleys, and the Upper Kaironk Valley as far west as Aynong Resthouse. 1.2 External relationships of Karam. Wurm states that Karam is related to but is not a member of his East New Guinea Highland? Stock, a stock to which he assigns 50 of the 60-odd languages spoken in the three Highlands districts of Australian New Guinea. On the basis of lexicostatistical and typological evidence (see Appendix A) Wurm claims that Karam, together with the East New Guinea Highlands Stock and several other languages spoken in Australian Highlands form a micro-phylum which he calls the East New Guinea Highlands

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  • The Function of Reciprocity in the Histories of Herodotus

    Paterson, Daphne (2002)

    Doctoral thesis
    The University of Auckland Library

    This thesis is an inquiry into the function of reciprocity in the Histories of Herodotus of Halicarnassus. It examines the complex ways in which the historian weaves reciprocity into his stories of kings and tyrants, citizens and slaves, city-states and empires, men and gods. It investigates the way he records relationships of personal, political and religious reciprocity, positive, negative and retaliatory reciprocity to illustrate his themes, explain the cause of events and characterise individuals and city-states. And it explores how he uses language to emphasise the significance of the obligation of reciprocity in his Histories. Herodotus explains the cause of events in terms of the personal obligation of reciprocity. He moves his narrative forward through interlinking chains of reciprocal action and reaction to show that the obligation to take revenge and repay favours is a catalyst for historical action. Herodotus uses reciprocity for the purpose of characterisation. He characterises individuals through his stories of their observance or transgression of the obligation of reciprocity, he contrasts good men with bad by recording their actions of reciprocity, and he characterises city-states through his accounts of the reciprocal actions of their people. Through this use of reciprocity, Herodotus imposes upon his audience a picture, either positive or negative, of the men, women, and city-states whose stories he tells in his Histories. This thesis is an examination of reciprocity in literature. It is a study of reciprocity as it is presented by a master story-teller whose literary representation of reciprocity is more complex and more interesting than reciprocity as it is presented in the writings of behavioural scientists. It is an investigation into the way reciprocity functions in the work of a man whose stories have entertained and charmed his readers for centuries.

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  • Different Realities: Challenging Conventional Ways of Conceptualising Delusions and Hallucinations

    Aschebrock, Yasmin (2005)

    Doctoral thesis
    The University of Auckland Library

    Delusions and hallucinations are typically regarded in contemporary Western societies as signs of serious mental illness - that is, as essentially meaningless surface expressions of a biological process, that are almost invariably distressing and harmful to those experiencing them. However, these conventional ways of conceptualizing delusions and hallucinations are increasingly being contested (by critical psychologists and by some of those who experience these kinds of phenomena). As part of this trend, this thesis highlights the need to move beyond traditional ways of construing delusions and hallucinations and to open up new ways of thinking about them. In Part One, I present analyses from an international survey of 58 mental health practitioners and researchers, which I conducted to investigate their understandings of delusional and hallucinatory content. I explore their views concerning the importance of attending to the content of delusions and hallucinations, and a possible relation between gender and the content of these phenomena. In Part Two, I present analyses of interviews with 11 women who have experienced delusions and hallucinations. I explore the linguistic resources available to those who experience delusions and hallucinations for talking about these kinds of phenomena, and the ways in which they may attempt to make sense of such experiences. I illustrate some of the challenges to traditional ways of conceptualising delusions and hallucinations by drawing upon the accounts of five of the women I interviewed. I aim, in this thesis, to question and disrupt conventional understandings of delusions and hallucinations and to increase the availability of some alternative (marginalised) ways of construing them. I emphasise the need to consider (and critically examine) the potential practical and moral implications of various ways of conceptualising delusions and hallucinations.

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  • Factors related to the pricing of audit services in New Zealand

    Neale, Ann Yvonne (1999)

    Doctoral thesis
    The University of Auckland Library

    Listed companies in New Zealand appoint an auditor, first, in compliance with statute mandatory appointment) and, second, to monitor agent (management) performance compared to principal (shareholder)preferences. The monitoring requirements of the audit contract should be reflected in the audit fee. In this thesis, I use Simunic's (1980) fee model to investigate three questions regarding the determinants of audit pricing. First, auditors have the incentive to earn fee premiums (quasi-rents) by developing specialised monitoring skills that address the needs of industries with a differentiated demand for monitoring. Three classifications of differentiated monitoring are developed to investigate whether fee premiums are earned on those audits. Fee premiums are shown to be earned by Big Seven auditors over non-Big Seven auditors, but the null hypothesis that industry specialist auditors do not earn fee premiums over non-specialists is not rejected. The incentive to earn quasi-rents in future fees provides a rationale for auditors to bid a reduced audit fee in order to gain incumbency (DeAngelo, 1981a). The second research question uses a sample of audit fees from the first financial statements after listing to test for reduced fees on initial audits. Results indicate that audit fees for the first financial statements after listing are lower than the level of audit fee for existing companies. Negotiation of audit fees may be affected by professional regulation. The third research question investigates whether abandonment of a fee scale by the professional accounting body in New Zealand influenced the general level of audit fees. The results fail to reject the null hypothesis that there is no difference in fees before and after abandonment of the fee scale. The incentive to develop industry-specialised monitoring skills may be replaced, in a small country, by alternate audit practice development strategies; for example, diversification of an audit portfolio in order to spread risk. Auditor brand name, reflecting technical skills, may thus earn a fee premium in preference to industry specialist skills. A final limitation of this work arises from the time period of interest (1985-87), a time of change in New Zealand's business environment, in which audit fee determinants may be subject to effects not captured in this thesis.

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  • The fractal modelling of turbulent surface-layer winds

    Lauren, Michael Kyle (1999)

    Doctoral thesis
    The University of Auckland Library

    Multiscaling analysis and cascade simulation techniques, which form part of the more general field of fractals, are introduced as a method for characterising and simulating surface-layer winds, particularly for time scales associated with the energy-containing range. This type of analysis consists of determining the power-law parameter of the spectrum of the data, and the scaling of the statistical moments. These techniques were applied to determine how the statistics depended on the duration (or scale) of the fluctuations in wind speed, the atmospheric conditions, and the topography of the site. It was found that the parameterisations produced using multiscaling analysis characterised differences in the statistics for each of these cases. Furthermore, the fractal cascade simulation techniques used provided simple methods for reproducing these statistics. This analysis is followed by an investigation into the robustness of some of these results. In particular, the data is examined for the existence of self-similar distributions of the cascade weighting factor, W. Such self-similar analysis allows the direct simulation of the data via a cascade. Cascade models have the virtue of being able to reproduce statistical properties such as intermittency, and in particular, the nesting of intermittency from different wavenumber bands in the same region of space. The existence of these properties in both the experimental and simulated data is investigated, with consideration given to the consequence of the results for simulation techniques. One notable discovery is the failure of these methods to reproduce the bias in the distribution of the gradients in the wind velocity field. This result has important implications for all workers dealing with simulation of geophysical data by fractal cascades. Finally, a brief numerical experiment is carried out to both demonstrate how this bias may be exploited to construct a model, and to test some of the analysis techniques presented on non-cascade based data. While not a particularly convincing simulator of turbulence, the model nevertheless displays some interesting turbulence-like characteristics.

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  • Associations between social anxiety disorders and the social aspects of young people’s Internet and mobile phone use

    Madell, Dominic (2007)

    Doctoral thesis
    The University of Auckland Library

    This thesis reports two surveys of young people’s use of the Internet and mobile phones. The first of these surveys was conducted on paper and provides a general description of young people’s Internet and mobile phone use in the Teesside area of England. The second survey was conducted online with a wider population and provides data to support the paper survey. Together, the surveys indicate that there may be a small bias towards male use of and competence with the Internet. There may also be a small bias towards female use of mobile phones. Results concerning non-use of the Internet and mobile phones are also discussed. Non-use of the Internet may often be due to a lack of access to facilities, and non-use of mobile phones may be due to a perceived lack of need for this technology. In addition, this thesis investigates relationships between social anxiety and social phobia and young people’s use of the Internet and mobile phones. It is revealed that associations between these conditions and use of these technologies, generally, and for communication purposes, are minimal. A Confirmatory Factor Analysis (CFA) of the two scales used to measure social anxiety and social phobia, which confirms their suggested structure, is also presented by the thesis. Finally, a focus group study of young people’s Internet and mobile phone use, which was analysed using Grounded Theory, is described. This was conducted to allow issues other than social anxiety, which might be relevant to young people’s use of the Internet and mobile phones for communication purposes, to emerge. It was found that control over interactions might be one important reason why young people like to use text-based Internet and mobile phone communication media to interact.

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  • Fluorescence lifetime measurements using a synchronously pumped dye laser

    Davis, Lloyd Mervyn (1984)

    Doctoral thesis
    The University of Auckland Library

    Experimental techniques for measuring fluorescence lifetimes were evaluated for the purpose of studying the fluorescence quenching of the biologically important dye ethidium. A synchronously pumped cavity dumped dye laser was used to produce stable high repetition rate picosecond pulses for sample excitation. A system was established for recording nanosecond decay profiles by time correlated single photon counting. A careful investigation of the factors which contribute to the instrumental time jitter enabled an overall impulse response of 600 ps to be achieved. Software was developed for analysing fluorescence decay profiles by the method of convolution and curve fitting and its capability for accurately resolving multiple exponential components was evaluated using simulated data. Some improvement in accuracy was obtained by modifying the Poisson weights used in the curve fitting routine to allow for non-statistical errors, caused primarily by the wavelength dependence of the time response of the single photon counting photomultiplier. Fluorescence polarization effects are discussed. The rotational lifetime of Rhodamine 6G in ethylene glycol was determined by measuring the fluorescence polarization anisotropy decay and the Debye-Stokes-Einstein theory reaffirmed for small molecules at moderate viscosities. The torsional rigidity of DNA can be determined by measuring the depolarization of fluorescence of tightly bound (intercalated) ethidium, and this was not observed to change appreciably when the antitumour drug amsacrine also binds to the DNA. The fluorescence quenching of DNA intercalated ethidium by anticancer drugs was studied by accurately resolving the fluorescence decay profiles into exponential components. The lifetimes and proportions are interpreted in terms of current theories for drug binding and fluorescence quenching mechanisms. The fluorescence quenching behaviour by the antitumour drug amsacrine is consistent with a previously proposed electron transfer mechanism.

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  • Osmium complexes as models for CO reduction intermediates

    Headford, Christine E. L. (1980)

    Doctoral thesis
    The University of Auckland Library

    This thesis is concerned with the synthesis, and aspects of the chemistry, of carbon-donor complexes of osmium as organo-metallic models for CO reduction intermediates. In Chapter 1 some aspects of ligand reactivity of the carbon-donor ligands CO, CS, CSe, CTe and carbenes in transition metal complexes are reviewed. The reduction reactions of these ligands are emphasized. The preparation and structure of the osmium η2-formaldehyde complex Os(η2-CH2O)(CO)2(PPh3)2 is described in Chapter 2. This complex has proved to be a useful synthetic precursor for stable osmium formyl, hydroxymethyl, methoxymethyl and halomethyl (-CH2X, X = Cl, Br, I) complexes and some facets of the reactivity of these ligands have been investigated. A general synthetic route to neutral osmium formyl complexes Os(CHO)X(CO)2(PPh3)2(X = halide or alkyl) has been developed. The facile preparation of a stable example of an intermediate formed during decarbonylation of a simple aldehyde by a transition metal, the osmium monohapto-acetyl-hydrido complex Os(η1-C[O]CH3)H(CO)2(PPh3)2, has been demonstrated. A preliminary study of the reactions of the osmium iodomethyl complex Os(CH2I)I(CO)2(PPh3)2 is reported in Chapter 3. The typical reaction of this species is nucleophilic substitution; in many respects reactivity is analogous to an electrophilic methylidene complex. Reaction with a variety of nucleophiles [e.g. OR-, H-, EH- (E = S, Se, Te), NH2R and PR3] has been investigated and the ligand reactivity of some of these derivatives studied. A synthetic route to η2-CSeS and η2-CSe2 complexes of osmium without the use of molecular CSeS or CSe2 has been developed and the isolation of the geometrical isomers of the η2-CSeS complex Os(η2-CSeS)(CO)(CNR)(PPh3)2 (arising from η2-C,S or η2-C,Se coordination) has been achieved. The synthesis of a stable osmium hydrido-selenocarbonyl complex, OsHCl(CO)(CSe) (PPh3)2, has allowed the direct observation of hydride transfer from metal to CSe ligand. These latter results are discussed in Chapter 4.

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  • A Conductive film model for the kinetics of the lead anode in aqueous sulphuric acid

    Hall, Simon Berners (1988)

    Doctoral thesis
    The University of Auckland Library

    The kinetics and mechanism of the anodic process on lead in aqueous 35% H2SO4 (4.65 mol L-1) were studied. The lead anode is of interest as it is used in the form of the sponge lead negative plate in the lead-acid battery. Discharge of both planar and porous lead electrodes result in the electrocrystallisation of PbSO4. In the past, the processes occurring at the lead electrode have been shown to include: dissolution, precipitation, and passivation. The techniques used were cyclic voltammetry, potential-step, and potential-ramp/potential-hold. The resultant transients were recorded both as analogue and digital waveforms. Investigations were carried out at a constant acid strength over a range of temperatures (-18° to 30°C), and in the presence of additives. Significant variation was found in cyclic voltammetry with regard to the cathodic potential prehistory immediately prior to measurements. After extreme cathodic polarisation (below -1500 mV us SHE), voltammograms were recorded with relatively high anodic peak currents and charges. The extra charge was associated with the growth of a multilayer, and dissolution from the bare electrode. This multilayer is not reduced on subsequent moderate cathodic excursions (above -1000 mV). Hence for cyclic voltammograms in the absence of extreme cathodic polarisation one observes relatively small currents and anodic charges. This is due to transmission of Pb2+ ions through the multilayer under resistance control. Passivation occurs in both cases by precipitation of microcrystalline PbSO4 on the multilayer. In contrast to cyclic voltammetry, potential-step transients were insensitive to cathodic polarisation and displayed current peaks due to growth of the surface film. One also observes a dissolution current from the bare electrode before it is covered by the growing film. The current first increases, passes through a maximum, and then decays with time. The increasing current was associated with growth of the multilayer, and the decaying current due to passivation by PbSO4. A new model was successfully applied to the potential-step and potential sweep results. The model consists of several charge-transfer reactions: growth of a multilayer, dissolution from the bare electrode, and transmission of Pb2+ through the multilayer. The kinetics of the multilayer are pivotal to the other charge-transfer reactions. The inclusion of film transmission is the novel aspect of this model. Quantitative analysis of the model resulted in a set of optimised parameters that follow plausible variation with anodic potential. Both the potential step and potential sweep transients are adequately described by the model. The effect of chloride added to the electrolyte was studied. The anodic and cathodic peaks in cyclic voltammetry are enhanced by this anion (100% more anodic charge at higher chloride concentrations) and the cathodic to anodic charge ratio is markedly increased. The general form of the potential-step transients are not modified by chloride. Evidence of a monolayer of PbCl2 was found (q = 500 µC cm-2) in both cyclic voltammetry and potential step experiments. The monolayer of PbCl2 must underlie the subsequent growth of the multilayer as the monolayer is first formed in potential-step experiments and first to be reduced in cyclic voltammetry at a small underpotential. The effect of methyl orange on the lead anode was explored and found to enhance the charge capacity. Battery tests confirmed these observations, but methyl orange was destroyed by the oxidising PbO2 at the positive plate. Hence a derivative, designed to be insoluble in H2SO4, was synthesised. However, experiments on both planer and porous electrodes showed that the derivative, lauryl orange, C12H25NHC6H4NNH+C6H4SO3- (pKa = 4.06) was found to act as an inhibitor for the anodic reactions. In particular there was no contribution from multilayer growth in potential step experiments, and only dissolution (markedly diminished) and passivation were evident. Lauryl orange exhibited the required capabilities to bind to lead metal. The structure of lauryl orange was confirmed by n.m.r. and mass spectrometry.

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  • The Atomic Trampoline Cavity

    Liston, Gregory John (1996)

    Doctoral thesis
    The University of Auckland Library

    Using an intense evanescent light wave as the lower mirror, and the gravitational force as the upper mirror, a vertical cavity for storing atoms can be constructed. Transverse confinement is obtained by totally internally reflecting the light off a concave as opposed to a planar crystal surface, which results in any atom reflected by the evanescent potential at a position away from the central axis receiving an impulse towards it. After a cursory discussion of atom optics and atomic cavities, we outline the configuration of the atomic trampoline cavity described above, and present analysis of the motion of atoms within it. A discussion of the classical dynamics and quantum modes in the cavity is given, together with other complicating factors which act as loss mechanisms out of the cavity. Various aspects of obtaining experimental realizations and applications of the cavity are considered. A detailed study of the quantum dynamics of atoms in the three dimensional cavity reveals that the dispersion can be adequately described in the transverse directions using a simulation involving a classical distribution of point-like atoms, where the probability density of finding an atom at a particular position in the simulation corresponds to the probability density of the atomic wavefunction. The classical simulations, however, significantly underestimate the spreading in the vertical direction. By calculating the modes of the atomic trampoline cavity, both in and out of the evanescent potential, the proportion of each of the modes in the excited state, and hence the decay rate, or linewidth due to spontaneous emission can be calculated. We found that even when the effect of the evanescent potential was included, the modes obtained correspond to those calculated by Wallis, Dalibard and Cohen-Tiennoudji [Appl. Phys. B 54,407 (1992)], who treated the bottom potential as infinitely steep and not exponentially decaying. In contrast to an optical Fabry-Pérot cavity, the linewidth was found to be strongly dependent on energy. Various other cavity parameters (finesse and Q) which depend on the loss due to spontaneous emission were also calculated. Using a ring cavity rather than a laser traveling wave to provide the light that totally internally reflects off the internal surface of the dielectric crystal, we can accumulate the phase change due to the single atom bouncing into and out of the evanescent wave and altering the refractive index of the cavity. A measurement of the phase of this light will reveal information about the atom. We found that the measurement did not significantly alter the mean or standard deviation of the atomic energy distribution across the modes of the cavity, as to first order the phase change of the light in the cavity is independent of the energy of the atom. The significant change in the energy distribution was the introduction of oscillations, which occurred when the phase measured was significantly different from the expected mean. The reason for these oscillations is that the measurement implies the weighting of modes just entering or leaving the evanescent wave should be increased or decreased. Ways of bringing this currently infeasible experiment closer to being achievable using novel design mechanisms are also discussed.

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  • Constructing a woman: gender, genre, and subjectivity in the autobiographical works of Sibilla Aleramo

    Jacobs, Susan (Susan Mary) (1994)

    Doctoral thesis
    The University of Auckland Library

    Both Sibilla Aleramo (1876-1960), one of Italy's most renowned and controversial women writers, and autobiography, as a generic minefield for debates on theories of the subject, have received a good deal of critical attention over the past fifteen years. The uncompromisingly autobiographical nature of Sibilla's work has been, at various times, revered and reviled, be it for what she says, or how she says it. My focus is precisely on the different forms she uses to write her self in four texts - a fictional autobiography, lyrical novel, epistolary novel and a diary - and how these construct, modify and deconstruct her self-representations in a continual process of intertextual reading and revising. Yet her texts resist easy classification. While sometimes confirming boundaries of genre and gender, they also constantly call them into question by exposing their limits, their intersection with fictional norms, and their shifting discursive affiliations. Because Sibilla was all her life concerned with gender, and the relationship of femininity to her writing, many aspects of her work appear relevant today. I explore how they anticipate feminist theories on the construction of female subjectivity in a combination of theory and autobiographical practice which highlights the interrelationship of the two. Here Sibilla's focus on the maternal is particularly indicative of this tendency, where it is woven into the generic structures of her texts as well as being an important focus of the autobiographical "story". Furthermore, her texts challenge the notion of self defined by male bias, and present opportunities for critical testing of autobiographical theories themselves by offering not one, but several, works for examination.

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