3,545 results for The University of Auckland Library, Doctoral

  • Flammability and durability of bamboo fabric reinforced polypropylene composites and their hybrids

    Mahmud Zuhudi, Nurul (2014)

    Doctoral thesis
    The University of Auckland Library

    Bamboo fabric has excellent mechanical properties and can also contribute substantially to fire resistance in composites. In this study, bamboo fabric has been used to reinforce polypropylene (PP) to produce eco-friendly composites. Hybridisation is a technique which may improve the strength and stiffness as well as the moisture resistance and flammability of natural fibre reinforced composites (NFRCs). The hybrid concept introduced here will reduce the use of the glass fibre in various applications. Bamboo fabric based PP composites were manufactured using compression moulding. The effects of processing parameters were investigated using Taguchi factorial analysis. PP composites with various bamboo and glass compositions were evaluated and compared. Physical, mechanical, thermal and dynamic mechanical properties of the composites were experimentally investigated. The tensile properties of the composites were compared to theoretical calculations. The incorporation of bamboo fabric in PP improves the mechanical properties as well as producing better thermal and dynamic mechanical properties. The incorporation of bamboo and glass fibres in PP improves mechanical, thermal, and dynamic mechanical properties in comparison to those of bamboo polypropylene (BPP) composites. A comparative study of flammability, durability, impact resistance and recycling of the composites was conducted to explore the potential of the BPP and hybrid composites. Flammability tests using a cone calorimeter showed that the hybrid composites performed better than the glass polypropylene (GPP) composites, exhibiting a reduction of at least 30% in heat release rate and smoke release as well as taking longer to ignite. Fire resistance was improved with the presence of bamboo. Hybridisation also improved the water resistance of the composites, the glass layer effectively acting as a barrier to slow down the penetration of the water. The presence of glass fibres preserved the mechanical properties after immersion especially at higher temperature. The presence of outer layers of glass effectively decelerates water diffusion into the composites. Impact resistance was improved with the presence of strong glass fibres and tough bamboo fabric. The hybrid concept, where several layers of glass in a GPP composite are replaced with bamboo fabric, shows promise for the production of high-quality, cost-effective light-weight composites.

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  • Magpies: negotiations of centre and periphery in settings of New Zealand poems by New Zealand composers, 1896 to 1993

    Shieff, Sarah (1994)

    Doctoral thesis
    The University of Auckland Library

    The thesis will show that a distinctive New Zealand voice in the arts may be found not in an "essence", as has sometimes been suggested, but at chronologically specific intersections of discourses. Each of the six works I examine has been made in New Zealand and is a mixture of music and language. As generic hybrids, combinations of music and language make appropriate objects of study for a thesis that explores a specific local dialogue between the 'mixture' and the 'essence', the 'hybrid' and the 'authentic', the 'indigenous' and the 'exotic', the 'local' and the 'imported', the 'centre' and the 'periphery.' Like acquisitive magpies, New Zealand artists constantly collect and select their material. They sift, save, reject and synthesise, and in so doing they create new combinations out of old ingredients. One of the characteristics of New Zealand poetry is that it has often been combined with music. There have been many collaborations between poets and musicians since colonial times. These collaborative texts occupy a complex space between art forms, just as New Zealand artists negotiate between orientations, positioning themselves between different cultural traditions. In its own process of selection, the thesis selects six works for close analysis which represent not only different periods but also different forms of synthesis. Each work represents 'New Zealand', yet what this means in practice is different in each case.

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  • About turn:neural mechanisms underlying visual processing of rotated letters and digits

    Milivojevic, Branka (2007)

    Doctoral thesis
    The University of Auckland Library

    This thesis explores neural activity associated with processing of rotated alphanumeric characters, focusing particularly on linear and quadratic trend components of orientation-dependent activity. Choice of these components was driven by results of reaction-time (RT) studies; judging whether characters are normal or backward (parity task) typically elicit RTs that are linearly related to character disorientation, implying mental rotation of the characters to the upright, while judging whether they are letters or digits (categorisation task) elicits RTs related nonlinearly to disorientation, combining both linear and quadratic component, but not indicative of mental rotation. In Experiment 1 neural activity was monitored using fMRI while participants performed these tasks. In the next two experiments, neural processing was monitored with high-density EEG. In Experiment 2 participants performed the same two tasks, while in Experiment 3 they performed the category task and red-blue colour judgements. In Experiment 1, linear increases in fMRI activation were elicited only by the parity task and were observed in the posterior portion of the dorsal intraparietal sulcus and lateral and medial pre-supplementary motor areas, suggesting a fronto-parietal network underlying mental rotation. Experiment 2 showed that linear increases in parietal negativity between 350 and 710 ms only evident in the parity task, again indicating that mental rotation is only elicited by that task. Contrary to previous evidence, Experiment 2 indicated that both hemispheres may be involved in mental rotation, but rotation is faster in the right hemisphere than in the left hemisphere. Experiment 1 also showed that effects of orientation common to both tasks were best characterised by a quadratic trend, and were restricted to the supramarginal gyrus. This activation was interpreted as representing orientation-dependent shape recognition. Experiments 2 and 3 also revealed orientation-dependent neural activity at three distinct stages prior to mental rotation. First, on the P1 component, there was a difference between oblique and vertical orientations, suggesting the extraction of orientation based on axis of elongation. Next, orientation affected the N1 component, with longer latencies and larger amplitudes with misorientation, and smaller effects for inversion than for intermediate angular rotations. Finally, changes in orientation affected the P2 component differently for the parity and category tasks, probably signalling the perception of orientation relative to a parity-defined memory representation, and serving as a preparation for mental rotation. These experiments identify both the orientation-specific neural processing that occurs prior to the onset of mental rotation, and the subsequent neural correlates of mental rotation itself.

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  • Amplitude resolution by human and ideal observers for Rayleigh noise and other Gaussian processes

    Hautus, Michael J. (Michael John) (1993)

    Doctoral thesis
    The University of Auckland Library

    The ability of human observers to discriminate aural differences in the amplitude of sinusoids, narrow-band noise, and wide-band noise was measured by the rating method of detection theory. Although each sinusoid (always 1000 Hz) was presented at a fixed amplitude, its amplitude on any trial was drawn from one of two Rayleigh probability distributions that differed in mean amplitude. Similarly, the amplitudes of the narrow-band noises were distributed as the Rayleigh distribution by virtue of the reciprocal relation between their bandwidth (100 Hz centred on 1000 Hz) and duration (10 ms). The amplitudes of the wide-band noises were distributed as chi with 82 degrees of freedom. A detection-theoretic model based on chi-square density functions was fitted to the obtained receiver operating characteristics (ROCs) and psychometric functions. The best-fitting ROCs required, on the average, 4.1 degrees of freedom for the 100-ms sinusoids and 7.3 degrees of freedom for the Rayleigh noise. The best-fitting psychometric function for both the Rayleigh noise and the sinusoids required about one degree of freedom. The results obtained for these two waveforms were not significantly different. The obtained ROCs for the wide-band noise were well fitted by the chi-square model with 82 degrees of freedom and the psychometric functions with 6.1 degrees of freedom. The best-fitting parameters for the wide- and narrow-band waveforms were significantly different. Furthermore, the performance of the observers on the nmow-band waveforms was closer to that of the corresponding ideal observer than was their performance on the wide-band waveforms. For the narrow-band noise and sinusoids, the duration of the waveform affected the variability of the best-fitting degrees of freedom for the obtained ROCs. This variability was greater for waveforms of 10-ms duration (Rayleigh noise and sinusoids) than for sinusoids of 100-ms duration; this greater variability was interpreted as stemming from the difficulty of correctly windowing short-duration waveforms. Sound pressure level had no effect on the amplitude resolution of observers for four different levels of Rayleigh noise and of sinusoids. Therefore Weber's Law, and not the near miss to Weber's Law, holds for these waveforms. The chi-square detection-theoretic model provided a good fit to the data from all experiments, but not as good as predicted by statistical theory. It was concluded that the chi-square model provides a close approximation to the underlying mechanisms involved in the amplitude resolution of Gaussian noise processes.

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  • Supply chain (re)alignment in New Zealand???s sheep meat and dairy industries : knowledge, networks and learning at the farmer-processor site

    Penny, G. M. (2003)

    Doctoral thesis
    The University of Auckland Library

    Emerging from the agricultural crisis of the 1988s, producers and processing companies in New Zealand's sheep meat and dairy industries, found themselves in an evolving neo-liberalised environment. By the late 1990s major structural (re) alignment had taken place in production and processing to accommodate shifts in markets and regulation, centring on 'food safety', 'quality' and "availability" For both farmers and processing company staff, this meant venturing into unfamiliar jointly occupied spaces and unchartered relational territory, Through a participatory research approach using multiple methodologies, this thesis examines supply chain (re)alignment at a macro and micro-scale, focussing on the farmer-processor relationship and knowledge, network and learning processes of farmers in (global) lamb and dairy supply chains in New Zealand. In seeking to account for evolving agri-food chain relations at multiple scales, this research turns to the global commodity chains (GCC) literature and draws on pragmatic solution-oriented ideas emerging from the developing field of Supply Chain Management (SCM). It also includes theoretical input from the cognitive and behavioural sciences to interpret the empirical data on farmer's knowledge, networks and learning in different supply chains, which it argues are key features of globalising agri-food economies. In this research these literatures and theories are enveloped by a broader yet, incomplete, theoretical foundation - that of evolutionary political economy (EPE), which is extended in this thesis, The thesis argues that an EPE framework provides a useful window on the governance of New Zealand's relations at a distance because it allows the specificity of micro-scale coordination activities and relations (in jointly occupied spaces) in New Zealand to be embedded in local and macro scale governance regimes and historical development processes. The findings show global market and regulatory pressures continue to drive supply chain (re)alignment in New Zealand, and chain building is occurring in different ways at the farmer-processor interface, between and within the different industries. Farmers' place specific on-farm knowledge co-evolves with off-farm knowledge through a combination of concrete experience, trial and error, socialisation and reflection, with both on and off farm knowledge becoming more overt in practice and strategy as supply chain specifications becomes more precise. Farmers utilise a range of networks (informal, formal, specialist and general), which serve as both information channels and learning forums. New Zealand's agricultural industries are like many in competitive globalising economies -'new' know ledge is being generated and used to broker global and local social, economic and environmental contexts and values, and in the process, supply chain partners' capacities and relations evolve.

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  • Degradation and utilisation of mucins by anaerobic bacteria from the colon

    Stanley, Roger Anthony (1982)

    Doctoral thesis
    The University of Auckland Library

    Intestinal mucins are high-molecular-weight complex glycoproteins which are thought to be fermented by the anaerobic bacteria in the colon. The aim of this thesis was to investigate the mode and extent of mucin degradation by bacteria. A method was developed to isolate gram quantities of soluble pig colonic mucin and pig gastric mucin. These preparations, along with commercially available pig gastric mucin, were incorporated into bacterial growth media as the sole carbohydrate energy sources. The molecular size and chemical composition of these mucins was determined before and after in vitro digestion by bacteria. Three different studies were done. In the first, type cultures of Bacteroides fragilis were found to be capable of growing on gastric and colonic mucins by cleaving residues from the non-reducing ends of the mucin oligosaccharide chains. Mucin degradation, however, was limited to the removal of only a few residues although this may be significant in vivo as bacteria in the gut lumen must be able to utilise many different complex polysaccharides and thus do not specialise in degrading any one substrate. In the second experiment, bacteria were isolated from the mucus layer of the pig colon. Three of the cultures studied extensively degraded mucins but colonic mucin was always more resistant to attack than the gastric mucins. Up to 80 mol% of the gastric mucin carbohydrates were cleaved and utilised. In contrast these bacteria utilised no more than 46 mol% of the colonic mucin carbohydrates. In the third study, fresh rat faecal material was used to inoculate bacterial media containing either colonic mucin or commercial gastric mucin. The faecal bacteria had completely degraded the gastric mucin after 24 h incubation but 36 h incubation was required to degrade the colonic mucin. However, when bacteria from the colonic mucin tubes were subcultured into fresh colonic mucin it was completely fermented after 24h incubation. It is hypothesis that, although the chemical compositions were similar, colonic mucin contained bonds that were not present in the gastric mucin. Evidence for this was obtained by assaying the mucins using the histochemical periodic acid/Schiff and Alcian blue stains. The Alcian blue reactivity was more conserved than PAS staining during bacterial hydrolysis. Therefore hydrolysis of these Alcian blue reactive groups may be the rate-limiting step in colonic mucin degradation. The molecular basis of the PAS and Alcian blue stains was investigated. PAS stain (0.01% periodic acid) was found to react with terminal neuraminic acid, fucose and possibly galactose residues but not with hexosamine residues. Alcian blue stain bound mainly to sulphate esters but could not be correlated with total sulphate content. When both these colorimetric Alcian blue and PAS stains were use together they provided a valuable tool for assaying the results of chromatography runs. Gastric mucin was show to be composed of separate neutral (Alcian blue negative) and acidic (Alcian blue positive) glycoproteins. Colonic mucin contained only acidic glycoproteins.

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  • Surface analysis of particulate emissions before and after atmospheric aging

    Henshaw, Geoffrey Stephen (1992)

    Doctoral thesis
    The University of Auckland Library

    The reactions and transformations of atmospheric primary particles have been studied using the surface analysis techniques of X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), Scanning Electron Microscopy (SEM) and Secondary Ion Mass Spectrometry (SIMS). Particles emitted from a steel mill were studied at their point of emission, during transport through the atmosphere and after deposition. The mill was located in a coastal region removed from other major industrial particle sources which made the identification of the mill particulate emissions possible in ambient samples. The mill utilizes indigenous titanomagnetite ironsand and coal as the raw materials. There is evidence of the surface enrichment of volatile trace elements such as Zn, S, Na, K and P from the raw materials in the particulate emissions. Particle samples were collected from sites within the mill which represented different stages in the iron-making process, including the rotary kilns, electric melting furnaces and the vanadium recovery plant. This established an inventory of particulate emissions. Mill sourced particles were then identified and studied in air samples collected downwind of the mill on silver-coated nucleopore filters. AES and SIMS depth profiling studies indicated the mill particles became surface enriched in sea salt components such as S, predominately as sulfate, Cl- and Na+ after atmospheric aging. This was attributed to their coagulation with the marine derived ambient aerosol. SIMS ion imaging and mass spectral analysis suggested a characteristic "fingerprint" of the mill emissions could be distinguished in the ambient aerosol up to 8 km downwind of the mill. An experimental rig was constructed to model the interaction between the mill particles and the natural marine aerosol. A bubble nebuliser was developed to produce an artificial sea salt aerosol which was reacted with a metal powder in the fluidised bed of the rig. The metal powder was then aged under controlled relative humidity (RH) conditions. It was shown that an iron powder, after reaction and aging at 75% RH, developed an aqueous surface layer which quickly led to electrochemical corrosion, dissolution and oxidation of the particle surface. Evidence of this corrosion of metal particles occurring in the environment was found in a SEM-EDX study of the mill particles deposited on pine needles downwind of the mill. It was argued that these reactions would increase the bio-availability of the particle components. A model which incorporated these observations was developed to describe the morphogenesis of atmospheric primary particles during aging in the New Zealand environment. XPS was used to study ambient aerosols deposited on both botanical and artificial passive sampling surfaces. Plant leaves were shown to be excellent collectors of particulate material and were suited to analysis by XPS. Site differences in the atmospheric aerosol load and composition were detected on vine leaves located on a hill side (high NaCl) and at a roadside (high sulfate and silicates) in a rural area. Zn and Fe species were detected by XPS on pine needles up to 2 km downwind of the steel mill.

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  • Kleva: some healers in central Espiritu Santo, Vanuatu

    Ludvigson, Tomas (1981)

    Doctoral thesis
    The University of Auckland Library

    Whole document restricted, but available by request, use the feedback form to request access. This thesis is an ethnographic account of the kleva of central Espiritu Santo, Vanuatu - a handful of healers credited with powers beyond those of their neighbours. Their concerns include matters like illness, sorcery, witchcraft, spirits and dreaming. The account is based on seventeen months field research among the Kiai-speaking population on the south-east side of the upper Ari valley in south central Santo. My method is primarily descriptive. In the main body of the thesis I give accounts of face-to-face encounters and conversations with the kleva and their neighbours, attempting to build up a picture of the kleva that takes into consideration not only what they do, but also the meaning of their activities for themselves and for their neighbours. In the conclusion I discuss the relevance of my material to some problems in the ethnography of Melanesian religions. I also raise issues of interpretation, seen to lie at the core of both topic and method in ethnographic pursuits.

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  • Facilitating independent learning early in the first year of school

    Watson, Barbara (1993)

    Doctoral thesis
    The University of Auckland Library

    This is a study of a) the nature and incidence of independent learning defined as "knowing how to generate and direct the processes of learning...*(see p.3) in new entrant classroom settings and, b) the nature of the teacher-child interactions associated with such independent learning. Systematic observation was used at school entry and three months later, to identify aspects of independent learning and the associated teacher behaviours. Six categories of child directed acts identified the range of behaviours from which independent learning could be inferred. Each category of teacher behaviour that appeared to facilitate independent learning in children was developed as a "mirror image" of each category of child directed acts. The teacher and four children in two new entrant classes were observed over the whole day for five days during two observation periods, one at the beginning of Term three and the other after 12 weeks. Each class was involved in normal classroom activities that covered the whole curriculum. The children were engaging in a considerable amount of independent learning on entry to school and three months later. Many facilitative teaching acts occurred in the interactive style that was demonstrated in all aspects of the curriculum. The teachers spent a considerable portion of teaching time assisting children in one-to-one teaching situations and in small groups, encouraging their responses and fostering and supporting independence in their learning. There was some difference observed between teachers in the attention given to different categories and in the facilitative behaviour occurring in one-to-one interactions and small group teaching interactions. A way of teaching emerges that differs from a teaching agenda determined by didactic, traditional instruction. The two teachers were deemed to be using the children's agenda to foster and support them in independent learning in the various curriculum areas. Some of the practical and philosophical features of the New Zealand education system that may contribute to this particular style of teaching are discussed. The theories of learning and teaching deriving from this study place a value on independent learning (as here defined) in new entrant children and on the teacher???s role in providing opportunities for it to develop. Independent learning a) ensures the continuation of learning at times when the teacher is directly engaged with other children, and b) derives from a teacher expectation that children will be able to actively process ideas and make some decisions about their learning. It engenders a power in children that sustains the momentum of learning.

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  • Frederick Weld: a political biography

    Williams, Jeanine Marie (1973)

    Doctoral thesis
    The University of Auckland Library

    Images removed from thesis for copyright reasons. Frederick Weld arrived in New Zealand early in 1884, an unassuming and shy twenty-year old with high hopes and modest assets. He left the colony two decades later, a well-regarded and prominent citizen whose reputation was regarded by imperial authorities as ample qualification for appointment to a colonial governorship. Following a successful term of office in Western Australia, he was promoted to Tasmania and thence to the Straits Settlements, from which post he retired in 1887. The purpose of this study is to demonstrate how Weld???s colonial experience greatly influenced the nature of his administrations and to illustrate how his outlook gradually changed from one of a colonist to that of a servant of empire.

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  • Judgement as play: revealing analogies between aesthetics and ethics

    Kovach, Vanya (1993)

    Doctoral thesis
    The University of Auckland Library

    This thesis is about the similarities of process between aesthetic experience and ethical judgement. I claim that in both cases the activity is best described as a type of play in which elements interact in mutual adjustment and transformation. This conception of play has its roots in Kant's aesthetic theory. Describing aesthetic experience as play results in emphasis on three central characteristics. These characteristics become the basis of constraints on judgement. In the case of ethical judgement these are important because they save from subjectivism a moral theory, particularism, which relies on individual judgement rather than moral rules. Seeing the activity of judgement as play suggests a conception of the outcome of judgement as picturing. This conception helps to make sense of reason-giving within the particularist model. A further analogy with the grounds of aesthetic qualities is used to illuminate the problem of justifying the values put into play. These values are ultimately defended in terms of their relationship to human flourishing. Perennial problems for theories based on human flourishing are avoided by my account because prescriptions for action are not derived from the characterisation of flourishing but from the process of individual judgement which values based on flourishing merely inform. One positive effect of adopting my model of judgement as play is the reduction of problems concerning the motivation to act on ethical judgements.

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  • The paradigm shift in Bible translation in the modern era : with special focus on Thai

    Doty, Stephen Howard (2007)

    Doctoral thesis
    The University of Auckland Library

    In the last two decades there has been a significant shift in Bible translation, away from the approach developed by Eugene A. Nida of the United Bible Societies. The practice of Bible translation in the modern era was greatly influenced by Nida, and still is to a great extent. His ???functional equivalence??? approach to translation gave priority to communicating the meaning of the text instead of merely retaining the form. His approach also included testing the translation to ensure that average readers understood the meaning. Nida???s approach was expanded upon by the Summer Institute of Linguistics (SIL) into what is known as the ???meaning-based??? approach. The difference between it and the functional equivalence approach is mainly one of degree, with the meaningbased approach being freer in several respects than Nida???s approach. However, there has been a movement away from Nida (as well as SIL???s meaning-based approach) among many Bible translators. The reasons for this shift are varied, although one major influence has been the growing awareness that the language communities who are the recipients of these translations should have a major part in deciding what kind of translation will be prepared. Such communities often prefer more literal translations. Yet they are seldom given the background information they need to make an informed decision about what approach is appropriate for them, partly because no studies exist which document the objective evaluation and comparison of different approaches to translation of the Bible. This thesis documents actual testing of three types of translation in the Thai language to determine which one most clearly communicates the meaning of the Bible. It was found that the meaning-based translation communicated most clearly for some stories that were tested, the functional equivalence translation achieved the second best results, and a semi-literal translation had the most significant communication problems. The findings also provide dramatic evidence about the limits any translation of the Bible has for people who have never heard its message before. This thesis also describes a new kind of testing of translation quality which the author developed in order to objectively compare different translations in Thai. Subjects were asked to read translated passages and then take a written multiple-choice test about the meaning of the translation. This new kind of testing has several advantages over the kind of testing in general use by most Bible translators.

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  • Anodic films on Bismuth

    Williams, David Edward (1974)

    Doctoral thesis
    The University of Auckland Library

    This thesis deals with the nucleation, growth and defect structure of anodic oxide films formed on bismuth in aqueous electrolytes. The early stages in the formation of continuous anodic layers of bismuth oxide were studied using the technique of cyclic voltammetry. During this period, the oxide, Bi2O3, covered the surface by a process of simultaneous thickening and spreading of patches. The study of oxide nucleation classified the metal surface into two different areas with different kinetics of oxide nucleation. The ratio of the two areas varied according to the history and original preparation of the surface. Film nucleation was also studied by the galvanostatic step and potentiostatic step methods. The rate of spreading of the oxide patches over the surface was shown to be controlled by the magnitude of the surface area still uncovered. Film thickening was studied using both galvanostatic and cyclic voltammetric techniques. The high field growth law i = ?? exp (B??) where i is the current density and ?? the field in the oxide layer, was found with parameters ?? = (1 ?? 0.5) x 10-5 A cm-2 B = (2.0 ?? 0.5) x 10-6 cm V-1 This value of B gives an activation distance for high-field ion transport, a* = 0.2 nm, comparable to the radius of a lattice site. These parameters were determined for very thin films in strongly alkaline electrolyte (pH 13; thickness 3 x 1018 cm-3. When the anodic film was formed in a solution containing bromide or iodide at pH 5, an inversion of the sign of the primary photo-effect from that observed in the absence of additives (4 nm thick film) was seen, and interpreted in terms of the photo-excitation of halide ions incorporated in the film. The lifetime of a conduction electron in anodic BiOI was determined as 1.5 ?? 0.2 ms, much less than in anodic Bi2O3 (23 ms). In all the studies of the photo-effect, Gauss' theorem was used to relate the observed photo-potential (galvanostatic experiments) to the photo-induced charge separation. An approximate value of the conduction electron mobility in anodic Bi2O3 was thus obtained: ?? ??? 5 x 10-8 cm2 V-1 s-1. Parameters for the evolution of hydrogen on the bare bismuth metal surface, were obtained: b = 0.11 V, log10(i0/Acm-2) = -10.3 and (???(log10i0)/???(PH))?? = 0 where ?? = E ??? 60 pH mV.

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  • Studies on the mode of action of the antitumour acridine 4'-(9-acridinylamino)methanesulphon-m-anisidide (m-AMSA)

    Wilson, William R. (1978)

    Doctoral thesis
    The University of Auckland Library

    1. The mode of action of a novel antitumor acridine 4???-(9-acridinylamino)-methansulphon-m-anisidide (m-AMSA) has been investigated. Two congeners of m-AMSA, 4???-(9-acridinylamino)methanesulphonanilide (AMSA) and 4???-(9-acridinylamino)methanesulphon-o-anisidide (o-AMSA) were also studied for comparative purposes. M-AMSA is being evaluated clinically at present under the auspices of the National Cancer Institute, U.S.A. 2. Treatment of mice bearing the mast cell tumour, mastocytoma P815, with m-AMSA provided some complete cures. AMSA was almost as effective as m-AMSA but its dose potency was 6-fold lower. o-AMSA was inactive. 3. m-AMSA was found to have a short half-life in mice. Loss of m-AMSA from plasma was due, in part, to the formation of highly fluorescent covalent protein adducts. The rate of this reaction was similar for all three AMSA congeners, and is probably not required for antitumour activity. 4. The reaction of AMSA drugs with proteins was shown to occur by nucleophilic displacement of the methanesulphonanilide moiety. Evidence is presented that the thiols are the predominant reaction centres in proteins. 5. A tissue culture model for the antitumour action of m-AMSA was developed using mastocytoma P815 cells. Profound growth inhibition and eventual killing was demonstrated using drug concentrations and durations of exposure attainable in mice. The potencies of the three AMSA congeners paralleled their antitumour potencies in vivo, except at very high drug concentrations. 6. The rates of biotransformation of AMSA drugs, and their extent of uptake by cells in culture, could not account for the differing potencies of the three AMSA congeners. 7. M-AMSA prevented the progression of mastocytoma cells through the cell division cycle under conditions where net cell growth was unaffected. Physiologically attainable drug concentrations inhibited chromosome condensation in cells which were less than 10 minutes from the G2-phase/mitosis boundary at the time of drug addition. The sedimentation rate on alkaline sucrose gradients of DNA from cells treated with m-AMSA was lower than that from untreated cells, suggesting that this agent may cause fragmentation of DNA. 8. A new method for the investigation of the cell cycle stage selectivity of antitumour drugs was developed. This technique demonstrated that m-AMSA and AMSA have significant cycle stage selectivity, the growth of cells late in cycle being most affected. 9. Spectrophotometric determinations of binding parameters for the interaction of AMSA derivatives with native DNA indicated that m-AMSA bound with lower affinity that did o-AMSA or AMSA. This conclusion was supported by the helix stabilization caused by these drugs. However, the association constants were sufficiently high for each derivative to ensure that essentially all intracellular drug available for binding to DNA would be bound. 10. The ration of the association constant for native DNA to that for a single-stranded viral RNA was higher for m-AMSA than for AMSA. This selectivity, if operative in vivo, could account for the high dose potency of m-AMSA.

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  • Biophysical studies of macromolecules

    Wills, Peter Rowland (1977)

    Doctoral thesis
    The University of Auckland Library

    Hydrodynamic theories of macromolecular structure have been critically examined and used in the experimental study of the conformation of various biological molecules. This work has been carried out giving careful consideration to ancient and modern wisdom. The fundamental molecular structure of liver glycogen has been investigated using a variety of biophysical techniques, including intensity fluctuation spectroscopy. It has been found that above a certain minimum size, molecules of this material are hydrodynamically equivalent to one another, and behave as if comprised of ideal spherical subunits. Smaller molecules do not have a smooth hydrodynamic surface and display a much higher degree of frictional interaction with the aqueous solvent. It has also been shown that when treated with disulphide-bond breaking reagents, large glycogen molecules are disrupted, but the structure of the subunits is undisturbed. The role of protein in glycogen structure has been confirmed by these studies. Intensity fluctuation spectroscopy has also been applied to the study of protein conformation. The frictional coefficients of bovine serum albumin monomers and dimers have been measured, and an apparent conformational change in the monomer detected upon the binding of salicylate. The unfolding and subsequent aggregation of lysozyme when it is thermally denatured have been observed and the hydrodynamic radii of the native, folded state and the expanded, unfolded state of protein have been measured. There is a well defined transition temperature for the denaturation process.

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  • Precept and practice in science an examination of some objections to theories of scientific method

    Noordhof, Jan W. Smith (1984)

    Doctoral thesis
    The University of Auckland Library

    One of the traditional aims of the philosophy of science has been to formulate a methodology of science???that is, a normative theory of scientific method. The rules and standards of such a theory are intended to capture the central features of scientific rationality and to explain the sense in which scientific knowledge progressively grows. Although no particular methodology of science has won universal endorsement, it is generally agreed among philosophers that the broad aim of constructing one is both reasonable and worth pursuing in order to understand the nature of scientific growth. But this aim has also been attacked as fundamentally misconceived by some critics who maintain that no theory of method can do justice to actual science. The objections to the philosophical program of framing a methodology of science come mainly from three quarters. Firstly, there is Paul Feyerabend, according to whom the historical development of science reveals that no set of general normative rules and standards can be given for science. Most of the rules and standards hitherto proposed, he contends, have been violated by scientists and, moreover, were necessarily violated, owing to the incommensurability of revolutionary scientific theories. Secondly, there is Michael Polanyi, who claims that scientific rationality cannot be codified in the explicit rules and standards of any theory of method because much of scientific knowledge and practice is 'tacit' and reflects the personal, unspecifiable contributions of individual scientists. And thirdly, sociologists of scientific knowledge (in particular, those of the Strong Programme) assert that the nature and content of science should be explained in sociological terms rather than by reference to a methodology of science. However, it is argued here that the objections made by Feyerabend, Polanyi and the sociologists to the possibility of a theory of method do not stand up to critical examination. A large part of the anti-methodologists' case is based not only on an overly narrow view of the nature of a theory of method, but also on the mistaken belief that the traditional philosophical and epistemological approach to the investigation of scientific rationality should be replaced by a largely descriptive analysis of scientific practice. This belief is criticised on the grounds that a normative methodology must not be supposed to explain scientific practice, nor can views on the nature of scientific rationality be derived from descriptions of scientific practice. Finally, it is suggested that the positions of Feyerabend, Polanyi, and the Strong Programme have deep affinities with the 'practice-oriented' philosophy of the later Wittgenstein. This may, perhaps, explain why they abandon realist construals of scientific theories, of scientific standards, and of the notion of truth. Like Wittgenstein, they adopt a form of antirealism and conventionalism which leads, ultimately, to a relativist interpretation of scientific standards and knowledge. Coupled with the anti-methodologists' failure to defeat the possibility of a theory of method, this relativism demonstrates the poverty of an attack on method constructed on wittgensteinian lines.

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  • An input-output model of Northland's economy: with application to forestry

    Moore, Chris (Christopher Ivor),1947- (1981)

    Doctoral thesis
    The University of Auckland Library

    This work presents a 50-industry input-output model of Northland's economy and demonstrates how input-output analysis could be used to enhance regional planning in New Zealand. As it is the first regional input-output model in this country to incorporate significant survey and secondary data the survey procedure and model construction are outlined. The input-output table is used to discuss important regional transactions and the purchase and sales patterns of industries. The model analyses industries' contributions to export receipts and import payments and calculates the impact of changes in export receipts on regional income and imports. A comprehensive multiplier analysis of Northland's economy covers output, income, employment and imports and confidence limits for the multipliers are developed using the Monte Carlo technique to simulate survey errors. The model explores the economic implications of forestry expansion in Northland and discusses the areas available for afforestation, planting rates, tree management, wood supply and wood processing options in the region. The modifications made to the model and data requirements for simulating forestry expansion are outlined and employment and income impacts given for three types of processing complexes and for forestry expansion as a whole. Finally an economic evaluation is made of the impacts of processing-plant construction and supporting services.

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  • Transcriptional promoters in a replication region of F plasmid

    Kennedy, Martin A. (1986)

    Doctoral thesis
    The University of Auckland Library

    This thesis describes aspects of genetic regulation within and near a replication origin (ori-1) of the F plasmid. A number of transcriptional promoters were isolated, precisely mapped, and characterized with respect to their strengths and modes of regulation. The principal techniques employed in these investigations were: "shotgun" molecular cloning of restriction fragments into a galactokinase-based promoter selection vector, assays for galactokinase activities, DNA sequencing and S1 nuclease mapping of transcripts. Major findings from this study can be summarized as follows: 1). Promoters for the essential replication genes pifC and E were cloned and shown to be autoregulated at the transcriptional level. 2). An E.coli protein, integration host factor (IHF), was found to modulate the activity of the pif operon promoter. 13). Two promoters which direct transcription in opposite directions from within the minimal ori-1 region were discovered. 4). Transcription from both ori-1 promoters was shown to be repressed by the mini-F encoded D protein. 5). Precise transcriptional startsites of the pifC gene and the two ori-1 promoters were determined. 6). A mini-F protein (D) was shown to resolve dimers of a plasmid which contains a site-specific recombination locus from near ori-1, and a facile assay system for this function was developed.

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  • Oxidation of Ring-A Aromatic Steroids

    Carlisle, Valerie F. (1969)

    Doctoral thesis
    The University of Auckland Library

    This thesis is concerned with a study of the oxidation of ring-A aromatic steroids using either chromium trioxide-aqueous sulphuric acid-acetone or chromium trioxide-aqueous acetic acid mixtures. It was found that chromic acid oxidation of ring-A aromatic steroids substituted with a strong electron-donating group, gives rise to products with the site of oxidation being predominantly that para to the activating group. Thus C-3 methoxy ring-A aromatic steroids give the corresponding 9b-hydroxy-11-oxo and 9-oxo-9,11-seco-11-oic acid derivatives as the major products and the 6-oxo derivative as a minor oxidation product. However, a ketol was not formed if a C-3 methoxy ring-A aromatic steroid also contained a substituent at C-1. The C-1-methoxy-4-methyl ring-A aromatic steroids give the 4-carboxy derivative as the major product and again the 6-oxo compound as a minor neutral product. The acetoxy and methyl substituted ring-A aromatic steroids, however, all give rise to the 6-oxo derivatives as the major products. The usual oxidation product of a ring-A aromatic steroid is therefore the 6-oxo product unless it is substituted with a methoxy group in a position which will stabilise an electron deficiency at a site other than C-6. Oxidation will then occur predominantly at the stabilised site unless it is sterically blocked.

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  • The Politics of insects: discipline and resistance in the cinema of David Cronenberg

    Wilson, Scott Alexander (2008)

    Doctoral thesis
    The University of Auckland Library

    This dissertation examines the films of David Cronenberg which all conduct a consistently thorough examination of the relationship between the ideologically constituted Cartesian subject and the disciplinary structures that surround, control and limit this subject. Cinema, because of the presence of both film form and narrative content, functions as a double articulation of this disciplinary activity. Each film???s narrative disciplines, on screen, the bodies contained within the plot, even as each film???s form disciplines both the way in which these cinematic bodies are delivered to an audience, and the way the audience???s own viewing practices are controlled and composed. Thus it becomes vital to explore the mechanisms implicated in these processes, and to gain an understanding of how Cronenberg???s cinema works to highlight and critique them. The primary assertion of this thesis is that Cronenberg???s work functions as a particular style of resistance to hegemony that Slavoj ??i??ek labels???heresy???. For ??i??ek,heresy occurs not when one disobeys one???s ideological requirements, but when one over-fulfills them, thereby extending these ideological demands and disciplinary discursive structures out to a site of logical absurdity. In assessing and charting this territory, the thesis is constructed in the following manner. The first chapter,which outlines my methodology, applies itself to a brief examination of Cronenberg???s least discussed commercial feature (Fast Company). Chapter Two is concerned with charting the disciplines applied to the body in Shivers, Rabid and The Fly, while Chapter Three continues a focus on Cronenberg???s movement and play with framing devices as a means of subverting a stable spectatorial position, utilising eXistenZ, Spider and The Dead Zone as examples. Chapter Four explores the manner with which heretical adherence to a single ideological construction pushes the protagonists towards large-scale disciplinary violations, as detailed in Crash, M. Butterfly and Dead Ringers while the fifth chapter examines notions of discipline and recuperation is focused on Naked Lunch, Scanners and The Brood. A final sixth chapter compares Cronenberg???s most recent film, A History of Violence, with Videodrome in order to explore the changing face of his disciplinary ambivalence and its relationship to a broader cinematic industry.

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