14,602 results for Doctoral

  • Modelling Cu, Zn, Cd and Pb Adsorption by Iron Oxyhydroxides in SO4-rich Systems Simulating Acid Mine Drainage

    Swedlund, Peter James (2004)

    Doctoral thesis
    The University of Auckland Library

    Acid mine drainage (AMD) typically involves waters with low pH (pH 2-4) and high concentrations of Fe, SO4 and potentially toxic trace metals. Adsorption onto iron oxyhydroxides is the dominant mechanism controlling the transport and toxicity of trace metals in water bodies impacted by AMD. The purpose of this study was to apply the Diffuse Layer Model (DLM) to describe the adsorption of trace metals by iron oxyhydroxides from these systems, using synthetic iron oxyhydroxide minerals, ferrihydrite, pure acicular goethite, SO4-rich goethite prepared from FeSO4 oxidation and a synthetic schwertmannite. The ferrihydrite adsorption of the trace metals Cu, Zn, Cd and Co from single sorbate systems was accurately described using the DLM with two surface site types (type-1 and type-2) having site densities of 0.005 and 0.2 mol (mol Fe)-1 respectively. The ferrihydrite adsorption of SO4 from single sorbate systems was accurately described using the DLM with adsorption on the type-2 sites. However, the enhanced adsorption of Cu, Zn, Cd and Co in the presence of SO4 was not predicted using adsorption constants derived from single sorbate systems. By including a neutral ternary complex with stoichiometry Fe(2)OHMeSO4 (where Fe(2)OH is a type-2 surface site and Me is the trace metal) the effect of SO4 on metal adsorption was accurately described for the range of Me, Fe and SO4 concentrations studied. The adsorption of Cu and Zn onto schwertmannite at total metal to iron ratios (MeT:Fe) up to 8 x 10-3 was almost identical to that predicted for ferrihydrite in the presence of 0.01 mol kg-1 SO4. To model the ferrihydrite adsorption of Pb from single sorbate systems a third higher affinity site (type-0) with a site density of 0.00035 mol (mol Fe)-1 was required. The effect of SO4 on Pb adsorption could only be modelled by including a neutral ternary complex on both the type 1 and type 2 sites in the case of Pb. Metal adsorption onto a pure acicular goethite could be accurately described by the DLM with two surface site types. The type 2 site density that provided the best fit to the goethite adsorption data was 0.027 mol (mol Fe)-1 corresponding to 2.3 nm-2. The type-1 site density that provided the best fit to goethite adsorption of Cu, Pb and Cd was 0.00028 mol (mol Fe)-1 corresponding to 0.024 nm-2. For Zn adsorption on goethite the type-1 site density was significantly larger at 0.0015 mol (mol Fe)-1 corresponding to 0.13 nm-2. In all cases studied the presence of SO4 caused an increase in the extent of metal adsorption by goethite. This increased adsorption of metals in the presence of SO4 was accurately predicted by including ternary complex formation at both the high and low affinity adsorption sites. For both ferrihydrite and goethite the values of adsorption constants for ternary complex formation (logKxMeTC) were related to the adsorption constant for metal adsorption in the absence of SO4 (logKxMeINT). This was evident from a plot of logKxMeTC as a function of logKxMeINT for all metals, which showed a linear relationship with slope of 0.69 and intercept of 8.03. This relationship suggests that the enhancement of metal adsorption on both oxyhydroxides due to SO4 occurs by the same process. When comparing Cu, Zn and Cd adsorption onto ferrihydrite and acicular goethite the effect of the larger goethite adsorption constants are approximately compensated for by the lower goethite site densities. Therefore the Cu, Cd and Zn adsorption isotherms on ferrihydrite and acicular goethite are fairly similar at low adsorption densities. In the case of Pb, the site densities and adsorption constants are both larger on ferrihydrite and there is a large difference between the ferrihydrite and acicular goethite adsorption isotherms. Sulfate-rich goethite had considerably higher site densities, per mol of oxide, than the pure acicular goethite. Adsorption onto the sulfate-rich goethite could be modelled reasonably accurately using the parameters developed to model adsorption onto the pure acicular goethite but with a higher surface area and a higher ratio of type-1 to type 2 sites. In general, therefore, the parameters developed for pure goethite are apparently similar to those for the sulfate-rich goethite, but are not directly transferable. The difficulty in measuring the surface area of the highly aggregated sulfate-rich goethite makes comparisons between the two goethites more difficult. The adsorption of Cu, Zn and Cd onto the SO4-rich goethite exceeds that of ferrihydrite because the higher adsorption constants of goethite are combined with the considerably higher site densities of the SO4-rich goethite compared to the acicular goethite. In contrast the higher site densities of the SO4-rich goethite does not completely compensate for the low logKINT values of Pb adsorption on goethite. Therefore SO4-rich goethite adsorption of Pb is lower than that of ferrihydrite. When applied to literature data from AMD oxides the parameters derived in this thesis have significantly improved the ability of the DLM to predict trace metal adsorption in AMD systems, compared to using ferrihydrite as a proxy for all iron oxyhydroxides and adsorption data derived only from single sorbate systems.

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  • A cyclical perspective of the common law

    Cadenhead, John. (1997)

    Doctoral thesis
    The University of Auckland Library

    This thesis is an attempt to use synthesis and analysis in respect of certain models of tort obligation to show that the common law has evolved and been shaped by recurring cycles. It was not possible to analyse the entirety of the wide sweep of tort obligation, so the models of trespass, trespass on the case, deceit and special relationship negligence were synthesised and then historically compared. From these models distinct recurring cycles of the common law became apparent, which alternated between expansionary and conservative stages. At one time the common law seeks a vehicle for new flexible remedies and obligations, and at another, it seeks the certainty of fixed rules. The cycle is incessant as for every swing in one direction, at a certain point on the pendulum, there will be a reaction. This thesis explores the pathology of those cycles through such selected models, including the symptoms exhibited by the initial ad hoc characteristics of the birth of a remedy or obligation, the maturing phase of a remedy or obligation created by the emergence of categories of liability, the abstraction from such categories of a general principle, and either the over-extension of such general principle, or the narrowing of such general principle leading to the obligation's ultimate demise as a flexible vehicle of liability. In the event of the death of an obligation or remedy, as a flexible vehicle of liability, the common law will seek to find or create another avenue of flexible remedy. The thesis does not seek to investigate the reasons or causes of such cycles, but is content to examine the symptoms exhibited by the various phases of such cycles. The initial two chapters summarise the general theory of such cyclic perspective and briefly outline the template of such cycles created by the early origins of the common law. The cycles of 'trespass' and 'deceit' show the rise and fall of those respective obligations from flexible remedies to narrow moribund obligations. The concepts upon which they were based of contra pacem and honesty were to prove excessively narrow and restrictive to survive the inevitable attrition caused through the natural accumulation of rules. A study of the cycle of these two obligations is rewarding as they both show a complete lifespan of an obligation through the various phases of a cycle up to the point of its death as an instrument of flexibility. The protean action on the case and the modern pragmatic case-by-case negligence formula, based on the open-ended elements of ‘foresight', 'proximity' and 'just and reasonableness', illustrate the problems caused by a remedy or obligation whose conceptualisation is vague and uncertain. The common law itself until 1875, apart from equity, had the ability through the action on the case to provide the common law with flexibility when needed. The closest that the common law in modern times has come to emulating the action on the case has been the remedial use of the negligence mechanism. While the action on the case did not survive the procedural reforms of the 19th century, it had developed general rules that limited the scope of such open-ended action. These general over-arching rules are important to a study of modern negligence liability. This thesis will endeavour to show that the modern open-ended negligence formula should be limited by comparable general rules to resist the inevitable pressure upon it to define its fault component or duty mechanism too narrowly. Synthesis by use of the tool of comparative legal history shows the constant tension in the common law between the quest for certainty through rules, on the one hand, and the ability to administer individual justice, despite the presence of a general rule, on the other. A comparison of the life cycles of the models selected shows a certain symmetry concerning the reasons and justifications advanced in constructing liability in either an expansionary or conservative phase of the common law. A cyclic perspective of the common law treats it as a dynamic constantly moving instrument that reflects the policy moods of contemporary society. Such a view of the law is not one-dimensional and may provide answers as to the past and present evolution of the common law and may give clues as to its future direction. The law is stated as at the 1st day of April 1997.

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  • Le Matuamoepo: competing 'spirits of governing' and the management of New Zealand-based Samoan youth offender cases

    Suaalii, Tamasailau M. (2006)

    Doctoral thesis
    The University of Auckland Library

    This thesis considers the 'spirits of governing' that currently frame youth justice approaches to Samoan youth offending in New Zealand, today. It claims that, in the current management of Samoan youth offending cases, three main spirits of governing are in play. These are the spirits of neo-liberal risk management cultural appropriateness, and faaSamoa. All three spirits operate simultaneously, in multilayered and intersecting ways. Gaining insight into this complexity is critical to building an understanding of the points of tension that may arise in the operationalisation of 'culturally appropriate' youth justice policies in the case of Samoan youth offenders. To highlight the complex character of these spirits of governing and their relationships, the thesis first describes each spirit of governing and then considers how they compete, intersect and/or diverge through a close analysis of seven youth justice cases. Analysis of each of the seven cases is based on interviews with a Samoan youth offender, a family representative, their CYFS social worker, police youth aid officer, Youth Court youth advocate and a community intervention programme worker. The key sites of government examined in this work are those of the family, the Youth Court, the youth justice family group conference and a community intervention programme service. The thesis reveals that to gain nuanced understanding of the complexities of managing a Samoan youth offender case, it is not simply a question of knowing what 'spirits of governing' are at play, one also needs to examine how they play. I contend that these three 'spirits' have specific relationships with each other. In youth justice, neo-liberalism opened up space for cultural appropriateness which, in turn allowed for the circulation of the faaSamoa. These three 'spirits', however, can not be reduced to each other because of their differing understanding of governmental strategies, techniques and subjects. In particular, they differ on their understanding of the role of families, of collaboration and of cultural expertise. Consequently, for example, while these three 'spirits of governing' 'agree' on the value of cultural appropriateness, they do not 'agree' on how it should be defined and measured. Too often when politically sensitive programmes or policies, such as those involving ethnic-specific cases, do not work, the response from politicians and programme personnel alike is to couch their failures in overly simplistic terms. This work seeks to indicate the importance of developing culturally nuanced models of analysis that can engage in the complexities of governing across cultural divides, in the improvement of practice in the field and in the development of a sociology capable of enhancing cross-cultural understanding.

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  • Model-based strategies for automated segmentation of cardiac magnetic resonance images

    Lin, Xiang, 1971- (2008)

    Doctoral thesis
    The University of Auckland Library

    Segmentation of the left and right ventricles is vital to clinical magnetic resonance imaging studies of cardiac function. A single cardiac examination results in a large amount of image data. Manual analysis by experts is time consuming and also susceptible to intra- and inter-observer variability. This leads to the urgent requirement for efficient image segmentation algorithms to automatically extract clinically relevant parameters. Present segmentation techniques typically require at least some user interaction or editing, and do not deal well with the right ventricle. This thesis presents mathematical model based methods to automatically localize and segment the left and right ventricular endocardium and epicardium in 3D cardiac magnetic resonance data without any user interaction. An efficient initialization algorithm was developed which used a novel temporal Fourier analysis to determine the size, orientation and position of the heart. Quantitative validation on a large dataset containing 330 patients showed that the initialized contours had only ~ 5 pixels (modified Hausdorff distance) error on average in the middle short-axis slices. A model-based graph cuts algorithm was investigated and achieved good results on the midventricular slices, but was not found to be robust on other slices. Instead, automated segmentation of both the left and right ventricular contours was performed using a new framework, called SMPL (Simple Multi-Property Labelled) atlas based registration. This framework was able to integrate boundary, intensity and anatomical information. A comparison of similarity measures showed the sum of squared difference was most appropriate in this context. The method improved the average contour errors of the middle short-axis slices to ~ 1 pixel. The detected contours were then used to update the 3D model using a new feature-based 3D registration method. These techniques were iteratively applied to both short-axis and long-axis slices, resulting in a 3D segmentation of the patient’s heart. This automated model-based method showed a good agreement with expert observers, giving average errors of ~ 1–4 pixels on all slices.

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  • Frequency selective wallpaper for mitigating indoor wireless interference

    Sung, Hui-Hsia (2006)

    Doctoral thesis
    The University of Auckland Library

    This thesis presents an effective technique for interference control with the use of frequency selective surfaces (FSSs) in indoor wireless environments. An FSS with a bandstop frequency response was applied to an existing wall as a wallpaper to transform the wall into a frequency- selective (FS) wall. The FS-Wall can be made to deliberately filter out undesired interference, and accordingly improve wireless system performance. In-situ measurements have shown that the FS-Wall prototype can attenuate 5.3GHz{5.8GHz (IEEE802.11a) transmissions by 15dB in addition to the unmodified wall attenuation, whereas other radio services, such as cellular telephony at 1.8GHz, experience only little attenuation. The FS-Wall created performed consistently (with acceptable attenuation levels) with varying signal incident angles from 0± to 56±. The 15dB reduction in signal strength is considered sufficient to isolate a system from external interference, and could potentially improve a WLAN system throughput by 2.2 times. The FSS performance has been examined intensely by both equivalent circuit modelling and practical measurements. Factors that influence FSS performance such as the FSS element dimensions, element conductivities, dielectric substrates adjacent to the FSS, and signal incident angles were investigated. By keeping the elements small and densely packed, a largely angle- insensitive FSS was developed as a promising prototype for FS-wallpaper. Such an FS-wallpaper can be applied directly to the wall (with no intervening spacing) with insignificant mutual interaction between the FSS and the wall. Accordingly, the resultant FS-Wall can be modelled by cascading the effects of the FS-wallpaper and the wall. Good agreement between the modelled and the measured results was observed, which suggests that the equivalent circuit model can be used confidently to assist FSS design. Fabrication techniques and practical installation issues associated with the development of FSS for indoor wireless applications were also investigated in this thesis. With the use of an angle-insensitive bandstop FSS, this research has demonstrated a feasible solution for mitigating external interference into indoor wireless systems. This research work has linked the fields of antenna design, communication systems and building architecture.

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  • Genetic and demographic investigation of population structure and social system in four delphinid species

    Oremus, Marc (2008)

    Doctoral thesis
    The University of Auckland Library

    Population structure, genetic diversity and social system were investigated in four species of dolphins, thought to present contrasting habitat preferences and social organisation: spinner dolphins, rough-toothed dolphins, long-finned and short-finned pilot whales. To overcome methodological limitations, I combined molecular markers (mitochondrial DNA, -or mtDNA-, and microsatellite loci) and observational data (photo-identification and mass strandings) where possible. Genetic samples were obtained from skin biopsies of free-ranging (n = 243) and stranded (n = 375) dolphins. As with many species of delphinids, spinner dolphins (Stenella longirostris) form communities in which social and reproductive boundaries are poorly understood. In French Polynesia, capture-recapture analyses based on photographs of distinctly marked individuals (DMIs) and microsatellite genotypes (12 loci) indicated a community of about 150 dolphins around Moorea that is relatively closed on a generational time scale. Distinct communities, likely to follow a similar demographic pattern, were observed around neighbouring islands (Tahiti, Raiatea, Huahine and Bora Bora), as indicated by photo-identification data and restricted gene flow (FST = 0.143, n = 154). Surprisingly high levels of insular mtDNA genetic diversity (average pi = 1.44%, suggesting Nef ~ 100,000) contrasted with demographic characteristics of these communities. There was no evidence for a recent bottleneck effect, suggesting that this pattern is the result of metapopulation structure, based on numerous insular communities connected through male and female gene flow. Investigation of the worldwide mtDNA diversity and phylogeography of long-finned and short-finned pilot whale species revealed a complex evolutionary history (Globicephala melas, n = 434; and G. macrorhynchus, n = 134, including published and unpublished sequences). Strong genetic differentiation between long-finned pilot whales from the North Atlantic (G. m. melas) and Southern Hemisphere (G. m. edwardii) indicated severely restricted gene flow, although shared haplotypes suggested some recent contact between the two subspecies. Low genetic distances among haplotypes and a star-like phylogeny suggested a recent worldwide expansion for this species. Higher levels of diversity (although low compared to other cetaceans) were found in short-finned pilot whales, in particular among samples from around Japan. Phylogeographic studies suggested that Japanese samples originate from three distinct populations, one of which could be the ancestral population of the species. Overall, my results confirmed that worldwide mtDNA diversity is low in the two species, probably due to a recent worldwide population expansion and, potentially, to a matrilineal social structure. The molecular ecology of the mass strandings of long-finned pilot whales around New Zealand was investigated to test the hypothesis that individuals stranding together are part of an extended matrilineal group. Analyses of mtDNA sequences indicate that more than one haplotype was found in five of the seven mass strandings investigated (n = 275), demonstrating that groups are sometimes composed of unrelated maternal lineages. This was further supported by analyses of relatedness within and between strandings based on microsatellites (14 loci). These analyses discount kinship as the only factor causing large mass strandings in long-finned pilot whales. Parentage analyses confirmed some aspects of previous studies in the North Atlantic, suggesting a social system with at least some level of male and female philopatry to the maternal group, and infrequent paternities within the group. In a detailed study of a large mass stranding (Stewart Island 2003, n = 122), there was no correlation between position of the whales on the beach and genetic relatedness (based on 20 microsatellite loci), discounting the assumption that kinship bonds are maintained during these traumatic events. This was further supported by the striking separation of stranded mothers and dependant calves. This disruption of kinship bonds could help explain the behavioural distress of stranded individuals and the tendency of many whales to re-strand even after being re-floated. Finally, a study of rough-toothed dolphins (Steno bredanensis) in the Society Archipelago, French Polynesia, provided new insights in the ecology of this poorly-known species. Although traditionally viewed as a pelagic dolphin, analyses supported a pattern of local communities, in some ways similar to spinner dolphins, with fine-scale population genetic structure (FST = 0.60, p < 0.001 based on mtDNA, n = 65) and local fidelity. These communities also showed a low level of mtDNA haplotype diversity (four unique haplotypes at Moorea compared to 18 for spinner dolphins), suggesting the potential influence of a matrilineal social structure similar to long-finned pilot whales.

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  • An analysis of the seasonal and short-term variation of road pavement skid resistance

    Wilson, Douglas James (2006)

    Doctoral thesis
    The University of Auckland Library

    It has been well proven that as the skid resistance of a road surfacing decreases, the number of loss of control type crashes increases, causing road death and injuries. However, the management of skid resistance of road surfacings continues to be difficult due to the inherent and sometimes random variation in skid resistance levels over time. This study is an investigation and analysis of seasonal and short term variation of measured skid resistance in two phases. Phase 1: Regular field monitoring was undertaken using the GripTester and the Dynamic Friction Tester measurement devices on seven sites in the Auckland and Northland Regions of New Zealand was undertaken over a three year period. The effects of temperature, rainfall, contaminants, new surfacings, geometric elements and aggregate properties were analysed to investigate factors that initiate changes in the measured skid resistance of pavement surfacings. Phase 2: Laboratory prepared samples were constructed for accelerated polishing and skid resistance testing of four different aggregates (two greywackes, a basalt and an artificial iron-making melter slag aggregate). The samples were polished in an accelerated polishing machine to an ‘equilibrium skid resistance’ level (Stage 1 polishing). Contaminants were then added to the accelerated polishing process to determine the effect of varying additive, particle size and hardness in an attempt to simulate seasonal and/or short-term variations that occur in the field. The results have demonstrated that significant and previously unpredictable variations (greater than 30%) in measured skid resistance can occur over short time periods. These variations cannot be explained by any one factor. They are the result of a number of inter-related factors, including the geological properties of the aggregates and the contaminants themselves, the previous rainfall history, the road geometry, the calendar month of the year and (depending upon the measurement device), the temperature during testing. The laboratory tests demonstrate that accelerated polishing tests of aggregate samples could be prepared for testing by the Dynamic Friction Tester and that significant variations in measured skid resistance could be simulated on various aggregates in the laboratory by the addition of contaminants. The results of the testing and addition of contaminants on various aggregates resulted in significant behavioural differences which were related to the geological properties of the aggregates themselves, as well as the contaminants used in the accelerated polishing process. The findings of the research have specific relevance to three areas of industry; Road Controlling Authorities who are primarily interested in skid resistance policy, standards and management, Road Asset Managers who operate, maintain and manage condition level and the safety aspects of the road network and Crash Investigators who collect and analyse crash data primarily for legal proceedings. All three of these industry organisations need to clearly understand the inherent variability of skid resistance, the factors involved and the effects that geological and environmental variations have on skid resistance measurement.

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  • Regulation of glucose transporters in sheep placenta

    Currie, Margaret J. (Margaret Jane) (2001)

    Doctoral thesis
    The University of Auckland Library

    Transplacental glucose transport is vital to fetal growth. Although the presence of glucose transporter-1 (GLUT1) and GLUT3 has been demonstrated in mammalian placenta, the factors regulating these genes remain unclear. Therefore, the overall aim of these studies was to clone ovine GLUT1 (oGLUT1) and oGLUT3 cDNAs, and to use these to investigate gene expression during ovine placental development and function. Ovine GLUT1 (~2.2 kb) and oGLUT3 (483 bp) cDNAs were isolated and cloned. Sequence analysis demonstrated that oGLUT1 showed high homology (97 - 99%) with other mammalian species, whereas oGLUT3 did not (84 - 88%). Northern analysis demonstrated that oGLUT1 mRNA abundance increased from d 45 to d 120 of gestation, then decreased towards term (d 145 ± 2), whereas oGLUT3 mRNA abundance increased throughout gestation. Western analysis showed oGLUT1 protein levels increased during late gestation, indicating post-transcriptional regulation of oGLUT1. Localisation experiments revealed spatio-temporal differences in ovine placental GLUT expression. In early gestation (d 45), oGLUT1 protein was restricted to fetal trophoblast cells. By mid gestation oGLUT1 immuno-signal was predominantly localised to maternal villous and endometrial tissue. By late gestation oGLUT1 mRNA was most strongly localised to maternal syncytiotrophoblast and villous tissue, whereas oGLUT3 was predominantly localised to fetal trophoblast cells. Placental oGLUT expression was regulated differently by acute (3 - 8 h) versus long-term (>6 d) alterations in late gestation maternal glucose supply. No evidence was found for regulation of placental oGLUT gene expression by long-term maternal undernutrition, but oGLUT1 and oGLUT3 mRNA and oGLUT1 protein were elevated by short-term (24 - 48 h) maternal hypoglycemia. Acute maternal hyperglycemia transiently increased oGLUT1 and oGLUT3 mRNA abundance, whereas oGLUT1 protein (but not mRNA) levels increased after long-term maternal hyperglycemia. Infusion studies provided no conclusive evidence for regulation of placental oGLUTs by long-term administration of growth hormone (GH) or insulin-like growth factor-1 (IGF-1) to the late gestation fetus. Following acute (4 h) fetal IGF-1 infusion, placental oGLUT3 mRNA abundance was greater in growth restricted (placental embolisation) than in normal fetuses, although the reason for this difference remained equivocal. This thesis describes isolation, cloning and sequence analysis of oGLUT1 and oGLUT3 cDNAs. These studies confirmed the presence of GLUTI and GLUT3 mRNA in ovine placenta, and demonstrated ontogenetic and nutritional regulation of placental oGLUT1 and oGLUT3. In addition, these results indicated that regulation of placental oGLUTs may occur at both transcriptional and post-transcriptional levels.

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  • Experimental manipulation of fetal growth

    Bloomfield, Francis Harry (2000)

    Doctoral thesis
    The University of Auckland Library

    Whole document restricted, but available by request, use the feedback form to request access. The experiments described in this thesis investigated the effects of low doses of insulin-like growth factor (IGF)-I on fetal growth and metabolism in normally growing and growth-restricted (IUGR) late-gestation ovine fetuses. Intra-amniotic and intravenous routes of administration were studied. The aim of the first experiment was to investigate the effects of daily intra-amniotic injections of IGF-I for l0 days to fetuses with IUGR induced by placental embolisation. Embolisation produced asymmetrical IUGR with moderately severe effects on the gut. Gut weight, gut wall thickness and crypt mitoses were reduced. Villus enterocytes in the ileum contained numerous vacuoles, suggesting either functional adaptation or delayed maturation. IGF-I treatment increased amniotic fluid IGF-I concentrations 5-fold, but decreased plasma concentrations. The effects of embolisation on the gut were reversed, except for the enterocyte vacuolation in the ileum which was more pronounced with IGF-I treatment. Fetal gut uptake of glutamine from the circulation was reduced in IGF-I treated animals, but uptake from amniotic fluid may have increased. Fetal liver and spleen size were reduced. The distribution of placentome types was also altered with IGF-I treatment. The aim of the second experiment was to investigate the clearance of 125I-IGF-I from amniotic fluid. The half-life of 125I-IGF-I in amniotic fluid was 24 hours. Significant amounts of 125I-IGF-I remained unbound for up to 144 hours in both amniotic fluid and plasma. The predominant binding protein in amniotic fluid was IGFBP-3, and the proportion of 125I-IGF-I that was bound in amniotic fluid was strongly correlated with relative levels of IGFBP-3. Uptake of intact 125I-IGF-I across the fetal gut was clearly demonstrated, and continued for at least 36 hours following injection. A preliminary pharmacokinetic model of intra-amniotic dosing with IGF-I is presented. The aim of the final experiment was to investigate the effects of a chronic intravenous infusion of a low dose of IGF-I to normally growing late-gestation fetuses. There were no effects of IGF-I treatment on fetal growth or metabolism. Five fetuses were found to be IUGR at post mortem due to the effects of facial eczema in the ewe. A post hoc analysis of the effects of intravenous IGF-I in IUGR fetuses was therefore performed. IGF-I treatment significantly increased growth rate of IUGR fetuses and increased fetal blood aminonitrogen levels. Mean placentome weight was increased and the distribution of placentome types was altered. IGF-I treatment of IUGR fetuses reduced fetal lactate production. There were no differences in measures of fetal body or organ size at post mortem. The data from these investigations into the experimental manipulation of fetal growth provide clear evidence of the reversal of some of the effects of established IUGR, demonstrate uptake of intact and free IGF-I across the fetal gut, and, for the first time, suggest that IGF-I may increase the rate of fetal growth in IUGR. Amniotic fluid is the most readily accessible fetal compartment. The experiments described in this thesis suggest that fetal supplementation with IGF-I via the amniotic route may be a feasible, efficacious and clinically applicable therapeutic stratagem for the IUGR fetus.

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  • The characterisation and application of natural fibre reinforcements for liquid composite moulding processes

    Umer, Rehan (2008)

    Doctoral thesis
    The University of Auckland Library

    Liquid Composite Moulding (LCM) processes are commonly used techniques for the manufacture of fibre reinforced plastic components. The range of LCM processes addresses manufacturing scenarios from low to high volume. This study explores the potential of natural fibres as reinforcement for LCM preforms, considering discontinuous fibre mats produced using several novel methods. Modified paper manufacturing techniques were employed to produce two types of wet formed wood fibre mats, the other two being manufactured using dry methods. The natural fibre reinforcements considered in this study have been characterised with regard to permeability and compaction response, such that their application to a wide range of LCM processes can be evaluated. Reinforcement permeability and compaction response data are required to simulate LCM processes. Permeability of all four types of wood fibre mats was measured as a function of fibre volume fraction. The dry compaction response of these mats has been investigated, with the compression loads being measured up to a fibre volume fraction of 0.4. A complex non-elastic compression response was observed which has significant influence on forces generated within moulds. Saturated compaction tests were also carried out, the samples infiltrated with a test fluid (mineral oil). These results were compared to typical glass fibre mats used for LCM processes. It was found that the wood fibre mats have permeability two orders of magnitude lower, and required significantly larger force to compact to at similar fibre volume fractions as compared to glass fibre reinforcements. Model fluids are used extensively for LCM characterisation experiments because of ease of handling and chemical stability. The influence of test fluid type on permeability and compaction response of four manufactured wood fibre mats has been determined using two different test fluids, a water based polar fluid (glucose syrup) and a non polar fluid (mineral oil). It was found that glucose syrup caused fibre softening and swelling which reduced the required compaction loads, and permeability of a wood fibre mat. On the other hand, mineral oil did not cause any fibre softening and swelling. The effect of geometrical parameters such as reinforcing fibre bundle diameter and length on characterisation was also determined. Six different types of flax fibre yarn mats were manufactured. A series of compaction tests were carried out on both dry and saturated samples. Saturated permeability was also measured at a number of fibre volume fraction levels. The fibre bundling reduced compaction forces and increased permeability of a mat. Composite panels were manufactured using an epoxy resin to visualise the penetration of resin into yarns and fibre cells. The reinforcement permeability and compaction response data were used to model two LCM variants, Resin Transfer Moulding (RTM), and Injection Compression Moulding (I/CM). A consolidation model approach was applied to simulate both RTM and I/CM processes, addressing a simple mould geometry. The RTM and I/CM clamping force traces, flow rates, and gate pressures were also measured. The simulation results have been compared with experiments completed for wood and glass fibre reinforcements at three different fibre volume fractions. It was found that at similar fibre volume fractions, the wood fibre mats produced longer mould filling times, and required larger forces to compact.

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  • Structure function studies on lectin nucleotide phosphohydrolases (LNPs)

    Chen, Chunhong (2008)

    Doctoral thesis
    The University of Auckland Library

    Lectin nucleotide phosphohydrolases (LNPs) are proteins which possess both apyrase catalytic activity (E.C. 3.6.1.5) and specific carbohydrate binding properties, and these are linked. To investigate the structural and functional properties for these proteins, two putative soluble plant LNPs, 4WC and 7WC (from white clover), and a putative soluble plant apyrase 6RG (from ryegrass) were chosen. Rabbit polyclonal antibodies for each plant apyrase were generated using highly purified, overexpressed recombinant 4WC or 7WC. In the case of 6RG, the C-terminal half of the protein constituted the best antigen for generating polyclonal antibodies. These antibodies showed high specificity and sensitivity. Active, recombinant 4WC and 6RG were overexpressed and purified using the baculoviral insect cell expression system (4WCbac-sup and 6RG:Hisbac), while 7WC (7WCcoli) was produced from E. coli inclusion bodies and subsequently refolded to give active enzyme. In course of overexpression, recombinant 4WC was localised in both the cellular fraction (4WCbac) and in the media supernatant (4WCbac-sup), while recombinant 6RG:Hisbac was only found in the cellular fraction (6RG:Hisbac) indicating that it was not secreted during insect cell growth. Secretion of 4WCbac was found to be dependent on N-glycosylation at N313 but not at N85 and elimination of one or both of these sites appeared to have little influence on apyrase activity. In addition, both 4WCbac and 6RG:Hisbac from the cellular fraction were fully functional. These results were compared with similar work performed on the animal ecto-apyrases which have different specific N-glycosylation sites required for secretion and activity. The 4WCbac-sup, 7WCcoli and 6RG:Hisbac proteins all showed apyrase activity, that is they catalysed the hydrolysis of nucleotide tri- and/or di-phosphates to their corresponding nucleotide monophosphates, and released inorganic phosphate in a divalent cation-dependent manner. However, the proteins exhibited different activities, substrate specificities, pH profiles and influence of inhibitors: 4WCbac-sup had a preference for NDPs with a pH optimum ≥9.5; 7WCcoli had a modest preference for NTPs with a pH optimum at 8.5; 6RG:Hisbac was almost exclusively an NTPase with a pH optimum at 6.5. Contrary to predictions based on phylogeny the proteins all bound to sulphated disaccharides and their catalytic activities were influenced both positively and negatively by the binding of specific chitosans. The data indicates that all three soluble plant apyrases investigated here were LNPs, in contrast to predictions from the literature. In order to pinpoint the regions responsible for determining substrate specificity and chitosan binding, chimeras were made using the N- and C-terminal halves of 4WC and 6RG. This resulted in fully functional reciprocal chimeras. Comparison of the apyrase activity for parents and chimeras, substrate specificity, optimal pH, influence of inhibitors on activity and effects of chitosans indicated that the C-terminus was responsible for determining substrate specificity. However, the influence of specific chitosans on the chimeras appeared to be dependent on both the N- and C-terminal portions of the proteins. In addition, chimeras were found to bind to the same sulphated disaccharides as the parent proteins. Preliminary crystal screening experiments were performed with highly purified preparations of 7WCcoli and 6RG:Hisbac. Under specific conditions 7WCcoli was found to form cube-like crystalline arrangements while 6RG:Hisbac formed hexagonal-like crystalline structures. A potential model for carbohydrate binding by LNPs is proposed and the possible biological roles of plant LNPs are discussed.

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  • Automated techniques for formal verification of SoCs

    Sinha, Roopak (2009)

    Doctoral thesis
    The University of Auckland Library

    System-on-a-chip (SoC) designs have gained immense popularity as they provide designers with the ability of integrating all components (called IPs) of an application-specific computer system onto a single chip. However, one of the main bottlenecks of the SoC design cycle is the validation of complex designs. As system size grows, validation time increases beyond manageable limits. It is desirable that design inconsistences are found and fixed early in the design process, as validation overheads are significantly higher after IPs are integrated. This thesis presents a range of techniques for the automatic verification and design of SoCs that aim to reduce post-integration validation costs. Firstly, local module checking algorithm, a practical implementation of module checking, is presented. This technique allows for the comprehensive verification of IPs such that they guarantee the satisfaction of critical specifications regardless of the SoC they are used in. Local module checking is shown to be able to validate IPs in much lesser time on average than global module checking, and can help in handling many important validation tasks much before the integration stage. Next, a number of protocol conversion techniques that assist in the composition of IPs with incompatible protocols is presented. The inconsistencies between IP protocols, called mismatches, are bridged by the automatic generation of some extra glue-logic, called a converter. Converters generated by the proposed techniques can handle control, datawidth and clock mismatches between multiple IPs in a unified manner. These approaches ensure that the integration of IPs is correct-by-construction, such that the final system is guaranteed to satisfy key specifications without the need for further validation. Finally, a technique for automatic IP reuse using forced simulation is presented, which involves automatically generating an adaptor that guides an IP such that it satisfies desired specifications. The proposed technique can generate adaptors in many cases where existing IP techniques fail. As it is guaranteed that reused IPs satisfy desired specifications, post-integration validation costs are significantly reduced. For each proposed technique, a comprehensive set of results is presented that highlights the significance of the solution. It is noted that the proposed approaches can help automate SoC design and achieve significant savings in post-integration validation costs.

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  • The Adolescent Mother and her Child: Determinants of Maternal Parenting Behaviour and Infant Development

    Dixon, Robyn S. (1995)

    Doctoral thesis
    The University of Auckland Library

    Despite having the second highest teenage pregnancy rate in the developed world, there has been an absence of New Zealand research investigating outcomes for the adolescent mother and her child The present study was designed as a first step toward redressing this situation. The aim of the study was twofold, to provide a descriptive profile of a sample of New Zealand women giving birth to their first child during adolescence, the primary aim being to identify psychosocial variables associated with maternal parenting behaviour and infant cognitive, motor and social development. One hundred and twenty, first time mothers aged between 15 years 6 months and 19 years and 9 months were interviewed in the post natal wards of Waitakere Maternity Unit in West Auckland. In addition to gathering extensive demographic data, measures of mothers' social support system, perceived stress, locus of control and knowledge of child development were taken. The second phase took place in the homes of the 80 subjects who were successfully located and agreed to further participate in the study. Again as part of this interview, demographic data were collected and, in addition to repeating the measures of social support and perceived stress, mother's satisfaction with her role as a parent was measured. Infant development was assessed using Bayley Scales of Infant Development. Finally, a 10 minute videotape was made of mother-infant interaction. During this time mothers were asked to change the infant's nappy, and then to play with their baby using a selection of age appropriate toys provided by the researcher. Following analysis of the descriptive variables, multiple regression analysis was used to identify variables associated with maternal parenting behaviour and infant outcomes. This resulted in the development of a model of adolescent parenting which suggests that social support, particularly the size of a mother's supportive network and the availability of emotional support, has a direct effect on maternal psychological status, which in turn impacts on maternal parenting behaviours. A mother's satisfaction with parenting being especially important. As expected maternal parenting behaviour is associated with infant interaction behaviour. Moreover, social support and maternal psychological status both had a direct impact on infant mental development scores. Furthermore, the results of the study have highlighted the importance of including measures of parenting satisfaction in models of adolescent parenting, a variable which up until now has been missing in research in this area. Finally, the implications of the findings for education and health professionals, and policy makers, concerned with the well being of these young women and their children are highlighted, and directions for further research identified.

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  • Bonding of additives to functional polyolefins by reactive blending

    Roberts, Ann Jennifer (2009)

    Doctoral thesis
    The University of Auckland Library

    This study examined the concept of using a reactive blending process to develop new polymeric additive systems. The objective was to investigate the potential of using a reactive processing technique as a means to bond additives to functional polymers, to create “in situ” bonds between functional groups present on the polymers and those present on the additives. The work is reported in two parts; the first part studied the bonding of colorants to functional polyolefins and the second part investigated the bonding of UV stabilisers to functional polyolefins. The research was completed with the long term objective that the approach should offer alternative additives to conventional non-bonded systems for use in polypropylene. An ethylene ionomer was utilised for the bonding of dyes, this was chosen for its optical clarity and chemical functionality. Polyethylene methacrylic acid (EMAA) ionomers and methine dyes were blended in the melt phase using an internal mixer to produce bright intrinsically colored polymers. Fourier transform infrared spectroscopy (FTIR) in transmission mode was used to assess the bonding of the dye to the ionomer. Bonding resulted through electrostatic interactions between carboxylate groups on the ionomer and cations on the dye molecules. The reactive blending process also resulted in a change in the chromophoric structure of the dye. The bonded system was compared to a system whereby no bonding between the methine dye and polymer was expected. In the later system the methine dye was blended with polyethylene using an internal mixer. From FTIR results no interaction was observed between the dye and polyethylene in this system. This was supported by microscopic analysis that showed that the dye was present in the polyethylene as a dispersion. The second stage of research focussed on the UV stabilisation of polyolefins. A melt reaction was explored between polypropylene functionalised with maleic anhydride (PP-g-MA) and an alkoxyamine hindered amine light stabiliser (NOR-HALS) with hydroxyl functionality. The technology proposed is based upon the reaction between the carboxylic acid groups of maleated polypropylene and hydroxyl groups of a specific NOR-HALS (Tinuvin 152). The efficiency of the modification was assessed using FTIR to verify the esterification reaction between the NOR-HALS and the maleated polypropylene. This reaction resulted in the grafting of a pendant UV stabiliser to the polypropylene through an ester linkage. A twin-screw extruder (TSE) was used to complete this study. A larger quantity of material could be produced using a TSE compared to the colorant system where an internal mixer was used. Samples of the reactively blended materials were exposed to UV radiation for a maximum time period of three hundred hours to assess the resulting stability of the materials. Diffuse reflectance FTIR (DRIFT) spectroscopy and X-ray photoelectron spectroscopy (XPS) provided an effective means to study oxidative degradation. IR spectroscopic measurements were used to determine the effectiveness of HALS in inhibiting the photo-oxidation of maleic anhydride grafted polypropylene. The inhibition was quantified by measuring the formation of carbonyl groups, with and without HALS bonded to the polymer, at fixed exposure times of UV radiation. DRIFT and XPS analysis confirmed that stabilised samples oxidised less, as indicated by the lower carbonyl index values and O1s / C1s ratios. These findings were complemented by results from Charpy impact tests. The mechanical property results indicated that the longevity of the materials with UV stabilisers grafted to them exceeded the PPg- MA system where there was no stabiliser present. Visible spectrophotometry was used to assess the colour of the polymeric samples and change in colour following exposure to UV radiation. Samples with bonded HALS demonstrated greater colour stability than control samples. The microstructure of the polymer surfaces was viewed using scanning electron microscopy (SEM). The polymeric samples demonstrated resistance to crazing when the NOR-HALS were bonded to the polymer. For both the colorant and UV stabiliser areas of research, thermal properties of the materials were assessed using differential scanning calorimetry (DSC). It was found that increasing the additive concentration in the polymer resulted in an increase in the temperature of crystallisation (Tc). Melt flow index can indicate if any change in molar mass had occurred during processing. An increase in melt flow index values (MFI) was observed when additive loading increased which suggested that degradation of the polymer had occurred during processing. In summary, reactive processing showed considerable promise as a means to bond additives to a functional polypropylene.

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  • SIMULATION OF COMPLEX MULTIPHASE, MULTI-COMPONENT, REACTING FLOWS IN POROUS MEDIA

    Zarrouk, Sadiq J. (2004)

    Doctoral thesis
    The University of Auckland Library

    In this study we are concerned with the modelling of multi-component, multiphase chemically reacting flows in porous media, with particular application to the spontaneous combustion of coal and the extraction of coalbed methane. These two related problems involve complex multiphase, multi-component flow in a porous medium. Chemical reactions, adsorption, gaseous diffusion and changes in porosity and permeability are important in one or both of these problems. These matters are discussed in general in the first few chapters of the thesis. Several models for the spontaneous combustion of coal that include the effect of a diminishing reaction rate are investigated and a new formulation in the form of a generic power law model is introduced. A numerical module for modelling the spontaneous combustion of coal is described, based on the TOUGH2 code. A new equation of state (EOS) module is developed including realistic physical properties for all gases involved. The modified version of TOUGH2 is used for modelling the adiabatic method for testing the reactivity of coal samples. The results agree very well with experimental measurements for coal samples from different mines in New Zealand and Australia. Moisture effect on the reaction rate was then introduced to TOUGH2 using a new twophase EOS module with water and air broken into its main components (Nitrogen, Oxygen, Carbon dioxide and Argon). Finally the production of methane from low rank coalbeds is investigated. A new EOS for mixture of water and methane is developed and incorporated into the TOUGH2 code to produce a new and versatile coalbed methane simulator. It is validated by running some simple test problems and comparing results with those obtained with the commercial COMET simulator.

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  • Sport-related injury: prediction, prevention, and rehabilitation - a psychological approach

    Maddison, Ralph (2004)

    Doctoral thesis
    The University of Auckland Library

    Two interrelated studies were performed to examine the role of psychological factors in the prediction and prevention of sport-related injury. As far as injury prediction is concerned, Study 1 tested the Williams and Andersen (1998) revised stress-injury model. It was hypothesised through the model that athletes with a history of stressors, a shortage of coping resources, and personality dispositions that augment the stress response, would be the most vulnerable to injury. Four-hundred and seventy-rugby players from 37-teams participated in the study and completed measures corresponding to variables in the Williams and Andersen stress-injury model at the beginning of the playing season. The number of injuries sustained and the amount of time loss due to injury were recorded throughout the season. Data were analysed using product moment correlations between life-stress and injury for groups of participants who fell in the upper and lower third of the moderator variables (i.e., coping resources—type of coping and social support, history of stressor—previous injury, and personality—competitive anxiety) distributions. As expected, a mild positive relationship was found between life-stress and injury time loss (r = .09, p < .05) and number of injuries sustained (r = .11, p < .05). Results also showed that previous injury, the type of coping, social support, and competitive anxiety interacted in a conjunctive fashion to produce a maximum moderator effect (explaining up to 29% of the injury variance). A second study (Study 2) was performed to determine whether a stress management intervention programme could effectively reduce injury among athletes identified from Study 1 to be most vulnerable to injury. A second purpose was to examine what might explain a positive result by exploring psychological (i.e., coping and anxiety) and stress response (i.e., reaction time and perceptual sensitivity) variables. Fifty-one rugby players from Study 1 who were found to be most vulnerable to injury (i.e., a rugby player with many recent life-stresses, high competition anxiety, inappropriate coping skills, and a history of previous injury) were recruited and randomly assigned to either an intervention (stress management programme) or a control condition. Participants completed psychological inventories at the beginning (Time 1) and end (Time 2) of the 2002 rugby season. Prospective and objective injury data were obtained for both number of injuries and time loss. In addition, a purpose built apparatus was used to assess stress response variables at the beginning (Time 1) and end (Time 2) of the 2002 rugby season. Prior to the start of the 2002 rugby season participants in the intervention group started a 6-session stress management programme that lasted 4-consecutive weeks. Emphasis was placed on how athletes could modify their reaction to stress. Participants were contacted monthly to reinforce the intervention, discuss implementation of the skills, and any relevant issues. ANCOVA results showed a significant condition (control versus intervention) effect for total time missed, but not for number of injuries sustained. Participants in the stress management intervention reported missing less time due to injury at the end of the 2002 season compared to their non-intervention counterparts. Furthermore, the intervention group appeared to only marginally increase the amount of time missed in 2002 compared to 2001, whereas the control group missed significantly more time due to injury. ANCOVA results provided some insight into the potential reasons for injury reduction. For the psychological variables, a significant condition effect was found for total coping resources. The intervention group showed an increase in the amount of coping resources at Time 2 compared to Time 1, and showed greater coping resources than did the control group at Time 2. The intervention group also showed a decrease in worry at Time 2 compared to Time 1 and less worry than the control group at Time 2. The condition effect for concentration disruption (CD) approached statistical significance, with the intervention group showing less CD at Time 2 compared to the control group at Time 2. For the stress response variables no significant condition effects were found for reaction times or perceptual sensitivity (d’). Overall, results support the recommendation that a stress management programme is effective in preventing further time loss due to injury for athletes with an “at-risk” injury profile. This result in part, is due to these athletes increasing their coping skills, and decreasing their worry and concentration disruption cognitions. In an extension of the prediction and prevention studies, a third study was conducted to examine the effectiveness of a psychological intervention (modelling) in affecting rehabilitation outcomes. Specifically the purpose of Study 3 was to investigate whether a coping modelling intervention could decrease pre-operative anxiety and perceptions of expected pain, as well as increasing rehabilitation self-efficacy and motivation associated with surgical reconstruction of the anterior cruciate ligament (ACLR). A second purpose was to determine whether the modelling intervention would be associated with improved functional outcomes in the early post-operative period (6-weeks) following ACLR. Sixty-four patients undergoing arthroscopic ACLR were randomised to receive a coping modelling intervention or to act as a control. Participants completed psychological inventories at different time periods during a 6-week period. In addition, the following functional outcomes were assessed, days walking with crutches, range of motion (ROM), and International Knee Documentation Committee assessment (IKDC). ANCOVA results revealed a significant condition effect for perceptions of expected pain, but not for state anxiety. Significant group differences were found for crutch self-efficacy, with the intervention group reporting greater self-efficacy than the control group. Repeated measure ANOVA results revealed significant time x condition effects for walking self-efficacy and exercise self-efficacy. No condition effect was found for jogging self-efficacy, nor were there any condition effects found for the motivation variables. ANCOVA results showed a significant condition effect (modelling) for functional outcome improvements (IKDC scores and crutch use) with the intervention group reporting superior IKDC scores and fewer days walking with crutches. No effects were found for ROM. Collective findings from the three studies highlight the importance of psychological factors in the prediction, prevention, and rehabilitation of athletic-related injury. Moreover, studies 2 & 3 support the use of psychological based interventions for reducing injury and augmenting traditional rehabilitation outcomes. Opportunities for future research are discussed.

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  • Characterisation of Poly (ethylene naphthalate)-based polymer blends

    Jung, Dylan D. B. (2003)

    Doctoral thesis
    The University of Auckland Library

    This investigation presents research on the characteristic properties of Nylon66 and poly(ethylene naphthalate) (Ny66/PEN), and poly(butylene terephthalate) and poly(ethylene naphthalate) (PBT/PEN) blends with several weight compositions made by melt blending, by the use of 13C and 1H Nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), Differential scanning calorimetry (DSC) and Dynamic mechanical thermal analysis (DMTA), X-ray diffraction (X-RD), tensile, impact and stress relaxation tests. Ny66/PEN blends including several additives do not improve the miscibility of the constituent polymers and show lower tensile strength than those of homopolymers. However, PBT/PEN blends reveal improved tensile strengths of the blends between the ROM and MROM predictions lines with more than 50 % volume fraction of PEN. On the other hand, NMR spectra show no evidence of interchange reaction in both Ny66/PEN and PBT/PEN blends. SEM micrographs of fracture surfaces in PBT/PEN blends reveal a very small (sub-micron) domain size in contrast to large domains in Ny66/PEN blends, which indicates partial miscibility of PBT and PEN. DSC and DMTA demonstrate partial miscibility of PBT/PEN blends by the change of Tgs of each component according to the weight proportions of the constituent polymers. Stress relaxation tests for the specimens of PBT/PEN blends and the homopolymers, using the Taguchi method of experimental design, determine that the most significant factor is the temperature, followed by PEN content and then the initial stress, and interaction effects between factors are insignificant. To fit the relaxation curves of the PBT/PEN blends and the homopolymers at different temperatures, PEN contents and initial stresses, four different equations have been used. The coefficients of the equation that fit best are used to predict the relaxation behaviour of PBT/PEN blends at a temperature between 30C and 60C, and at the initial stresses of 7 MPa.

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  • Connecting selves: relationship, identity and reflexivity on the 'frontline' in a New Zealand call centre

    Copas, Susan (2004)

    Doctoral thesis
    The University of Auckland Library

    This dissertation centres on process and connection. Beyond the popular concept of ‘worklife balance’ it presents an integral and holistic view of how work (including the ‘work’ of research), and life are inextricably connected. Eschewing the more conventional model of the PhD; it does not develop a question (or set of questions) about this area of interest, and then proffer answers. Rather, it works with/in an ever emerging flow of living relationships and experiences, to offer inclusive, constantly shifting understandings of the embodied dialogical processes that relationally construct and connect people, our ‘selves,’ in the everyday flow of life, work and research centred around a particular organisational setting: a large public sector call centre. The study rests on the assumption that rich multiply inflected emergent processes and relationships ‘make’ people and their worlds, including the world of research. Hence the dissertation is presented as an on-going construction, in which individuals and organisations are not autonomous entities, but are in-effect, always becoming. The organisation, its frontline staff, managers, and I (the ‘researcher’) emerge moment-bymoment, relationally made and remade, within the communicative realm of embodied language, in many different social, local, and historically inflected ways. In the field, this everyday becoming is explored using a hybrid form of organisational ethnography and collaborative action research. On the page, academic prose, stories and narrative poems combine and interweave to (re)construct and deconstruct the situated dialogues and relationships. Narrated in two parts, the first section - “Telling Stories” - works with contexts, scene setting and character development. Its layered and iterative unfolding begins with a day-in-the-life story of work, life and research at the call centre. The section then outlines the attitudes and assumptions that guide relational-responsive becoming, before detailing the political economic, organisational and personal backgrounds and values influencing this study. With/in the conversations and complications of collaborative practice I ‘show and tell’ how ‘coming to know what is known’ is a rich relational emergent process that reworks research away from the more traditional notion of it as data gathering and retrospective analysis. Part two - “Stories Told” - is the heart of this study. It brings a sense of emergence to life by focusing the kaleidoscopic lenses of relationship, identity and reflexivity on people-in-process within the dynamic interplay of call centre technologies, organisational systems and human interaction; both at work and outside of the workplace. The stories interweave the rich multidimensionality of emergent lives, as they explore the camaraderie and subversion of working in a tightly monitored and time pressured environment, amidst changing conceptions of what constitutes public service in New Zealand. Radically reflexive, they unsettle the often taken-for-granted assumptions, feelings, actions and words that make selves in life, work and research. In doing so, the stories raise expansive and inclusive possibilities for new ways of understanding each other, our knowledges, practices and experiences. They also remind us of the everyday, every moment possibilities for developing more mindful and holistic understandings of the relational processes and the communicative practices, within which we make our selves, our organisations, and our worlds. KEYWORDS: Relational Construction; Emergence; Reflexivity; Identity; Organisational Processes; Call Centres; Work and life; Public Sector; New Zealand.

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  • Deformation characteristics of knitted fabric composites

    Duhovic, Miro (2004)

    Doctoral thesis
    The University of Auckland Library

    A relatively recent innovation in the field of thermoplastic composites is the reinforcement with knitted structure that offers a number of potential advantages over the more conventional straight-fibre reinforcements. They can be stretched in both directions during forming, increasing the potential for forming complex and deeplycurved components and have excellent impact, fracture toughness and energy absorption properties. An understanding of some of the unique behaviour of these sheet materials during forming and the practical viability of various forming processes are crucial in assessing their applicability to given products and uses. The first part of this study concentrates on identifying the types of micro-level mechanisms that occur during the forming process of knitted fabric thermoplastic composite sheets. It has been proposed that knitted fabrics and textile composite materials, in general, follow a three-level hierarchy of deformation modes. The most important of these levels are the micro-level fabric deformation modes, which have been identified and specifically developed for study in this thesis. In order to study these modes, the material has been subjected to a series of simple inplane, single and double curvature forming experiments. The main purpose of the inplane forming experiments was to record tensile data that would later be used to establish the warp and weft direction modulus curves, important inputs for the numerical simulations. Grid strain analysis (GSA) was also performed to investigate the strains that occur during the forming of more complex shaped components and to verify the numerical simulation results. The experiments highlighted that the behaviour of the molten composite was very similar to that of the dry fabric at forming rates below 100mm/min and that the lubricating effects of chemical sizing on fibres in both the composite and the fabric were present. It was also found that a more even surface strain and thickness distribution could be attained using flexible tooling and higher forming temperatures. iii High fibre volume fraction knitted fabric composites were produced from 1x1 rib fabric made from commingled yarn at different pressures and temperatures. The material was able to match the stiffness and strength of a commercially available woven fabric product, Twintex®, for strains of up to 8%. An optimum forming pressure of 400kPa was found to give the best consolidation without causing fibre damage due to excessive compression. During the forming experiments the importance of the reinforcing structure was realised and provided the impetus for a detailed micro-level numerical investigation. The simulation involved the production of a narrow strip of 1x1 rib fabric and subsequent tensile testing. The model was verified in two ways: i) by comparing the physical and numerical specimens geometrically and ii) by using force displacement curves generated from the tensile tests on real specimens manufactured using the same knitting machine parameters. A correlation factor was defined to allow the comparison of numerical and physical specimens containing different numbers of fibres. Comprehensive analysis of the model revealed bending as the most dominant microlevel mechanism, followed by torsion, uniaxial tension and contact energy at low strain levels and bending followed by uniaxial tension, contact energy and torsion at high strain levels. In addition, macro-level numerical modelling was performed using the data gathered from molten tensile tests. A PAMFORM™ material model originally designed to model the sheet behaviour of unidirectional and woven composites was used. Minimum thickness strains showed close agreement. However, further development of the model is required to allow more accurate predictions of the surface strains and stability at very high strain values.

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  • "Building monuments more enduring than brass" : Governor Sir George Grey, a study of his book collecting and the formation of his libraries

    Kerr, Donald Jackson (2001)

    Doctoral thesis
    The University of Auckland Library

    This thesis documents the book collecting activities of Sir George Grey (1812-1898) and the formation of his libraries in Cape Town (1861) and Auckland (1887). As this bio-bibliographical narrative unfolds, the variety and richness of each collection is revealed. Much of what is presented on Grey the bibliophile is new and detailed here for the first time. Importantly, it reveals another dimension to one who was the most important nineteenth-century governor in the Southern Hemisphere. Coverage of Grey's life as a book collector extends from his early years at Bodiam, Sussex, to his last years in London, and includes those periods when he was governor in South Australia (1841-45), New Zealand (1845-53; 1861-68), and the Cape Colony (1854-186l). A bookish environment and a precocious willingness to engage in literary and antiquarian studies assisted a latent collecting instinct. This is nowhere more evident than in his early forays into the collecting of indigenous language materials and the collecting of natural history specimens in Australia. In his early years, Grey was fortunate to attract the attention of influential mentors such as Richard Whately, Richard Owen, and Sir John Herschel. Each played a part in encouraging his collecting. In later life, far removed from the centres of the book world, he continued to collect. As a committed bibliophile, it was a habit that he could not break. The book dealer plays an essential role in the book collecting process. Grey was fortunate to gain advice and friendship from some of the most prominent antiquarian book dealers in nineteenth-century England, including Henry G. Bohn, T and W Boone, and Bernard Quaritch. Others included Asher and Heberle–the so-called 'German Connection'–and booksellers representing the growing colonial book trade in New Zealand and Australia. This study examines his relationship with these men, what type of books he acquired, what he paid for them, and when they were purchased. His chief method of acquisition was through dealer catalogues, but he also obtained books and manuscripts through private individuals and auction houses. If a buying pattern is evident, it is one that is continuous, with a gradual accumulation of books over long periods. Grey also sought materials outside established book markets. His world-class collections of African, Maori, Pacific, and Aboriginal language materials were obtained by the patient development of networks with church officials, missionaries, explorers, linguists, and army and naval officers. Once again, each primer, catechism or word list was accumulated over a number of years. Full justice was given to these rare materials when they were documented in various printed catalogues that were instigated by Grey and completed by the philologist Dr Wilhelm Bleek. There are no barriers to the persistent collector, and Grey's success in overcoming the frustrations of supply and the problems associated with distance is measured by the libraries he collected. His position as Governor assisted the collecting process, and once his collecting preferences were known, items flowed in for inclusion. That he gave both libraries away in his lifetime is remarkable, an unparalleled action in the annals of nineteenth-century book collecting. Both remain testaments to his persistence and vision.

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