3,587 results for ResearchSpace@Auckland, Doctoral

  • Mathematical modelling of energy demand and supply in the cardiac myocyte

    Tran, Kenneth (2010)

    Doctoral thesis
    The University of Auckland Library

    The mechanisms that regulate the control of energy demand and energy supply in the heart muscle are crucial for maintaining normal cardiac function, yet they are not very well understood. Although a number of mechanisms have been proffered by which mitochondrial supply of ATP can change to match varying workload in the myocardium, identifying the underlying regulatory pathways remains controversial. In this study, we have developed mathematical models of the sarcoplasmic endoplasmic reticulum Ca²⁺ ATPase (SERCA) pump and the acto-myosin cross-bridge cycle which, along with the Na+/K+ pump, are the key energy-consuming processes in the cardiomyocyte. These models encapsulate both thermodynamic considerations and metabolite sensitivity into a cycle-based framework. The parameters of these models are constrained by experimental data which characterise their physiological behaviour. These models are then placed within the context of a whole-cell electrophysiological framework, alongside a model of mitochondrial energy supply, to investigate the mechanisms that regulate energy control and to shed light on two experimental observations which, for many decades, have evaded a mechanistic explanation: the apparent linearity of the VO₂- PVA (pressure-volume area) relationship and the metabolic stability hypothesis, wherein demand-supply homeostasis is maintained despite negligible variation in metabolite concentrations at varying workloads. The predictions from our model simulations indicate that, under constant metabolite concentrations, the ATP-FTI (force-time integral) relationship is linear, while the ATP- FLA (force-length-area, cellular equivalent of VO₂- PVA) relationship is linear only at low work rates. The linearity of the ATP-FTI relationship is found to arise from kinetic properties of the cross-bridge model. This property is not retained in the ATP-FLA relationship and is lost when metabolite concentrations are allowed to vary, as during normal variation with changing workload. This suggests that FTI and FLA are not equivalent, and that the VO₂- PVA relationship may only be approximately linear. Finally, we show that metabolite concentrations change significantly with increasing workload if Pi feedback onto mitochondrial oxidative phosphorylation is removed from the model, suggesting that Pi-regulation alone is sufficient to maintain metabolic homeostasis in the absence of other regulatory mechanisms.

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  • The right to health in practice:a framework to guide the design of aid-funded health programmes

    Williams, Carmel (2010)

    Doctoral thesis
    The University of Auckland Library

    More than 60 years have passed since the nations of the world united in acknowledging the inherent freedom, dignity and equality of all people in the Universal Declaration of Human Rights. Incongruously, ‘development’, another contemporaneous international movement, failed to embed these rights into its practices. As a result, millions of people in developing countries are still denied such rights as freedom from avoidable ill health and premature mortality, with development projects having focused instead on varying economic growth strategies. However, the past decade has witnessed a commendable global effort to reduce health inequities, with vast increases in health aid funding, particularly from the non-state sector to combat specific diseases. But after decades of neglect, the health systems of developing countries are struggling to accommodate these increased resources and many risk collapse. Without well functioning health systems, the right to health cannot be realised. In this thesis, health rights are investigated to seek solutions to these global health issues. I use a right-to-health framework to guide the design of aid-funded health programmes that meet health rights obligations, by working with and strengthening health systems. The thesis describes the development of a set of tools to design activities, then to identify their likely impact on a health system. The tools are derived from reviews of the literature and are tested for validity against case studies in Papua New Guinea. The three tools focus on: • respecting health rights by designing with a full understanding of the health system • fulfilling health rights by designing available, accessible, acceptable and quality services • protecting health rights by conducting a health systems impact assessment. The case studies revealed that the tools were relevant and feasible, and provided a means of early identification (and subsequent avoidance) of negative programme outcomes. Health rights offer a new global health diplomacy; a means by which all parties can be accountable and transparent in their legal duties to respect and protect health systems, so health rights can be fulfilled. Importantly, this framework provides a means of demonstrating that interventions, at the health systems level, do no harm.

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  • Effect of inter-cultural contact on L2 motivation and L2 learning: A process product study

    Aubrey, Scott (2015)

    Doctoral thesis
    The University of Auckland Library

    The purpose of this mixed-method, classroom-based research is to determine the effect of face-to-face inter-cultural contact on Japanese university EFL students’ L2 motivation and language learning. From a pedagogical perspective, this study provides an example of how, at a classroom-level, EFL teachers can utilize the international student body to generate intercultural contact opportunities. Investigating the effects of inter-cultural contact is particularly relevant in Japan as this issue is in line with recent government initiatives that seek to internationalize education at Japanese universities. Thus, one of the goals of this study is to evaluate the motivational and language learning benefits of such an intervention. This thesis examined the effect of inter-cultural contact from a number of theoretical perspectives, which included changes in students’ motivational self-concept, the extent to which contact manifested ‘flow’ during interactions, interaction-driven language learning opportunities, and self-reported language learning outcomes. This research employed a quasi-experimental design in which the intra-cultural and inter-cultural contact was provided to learners via dialogic, oral tasks. Task performances of the Inter-cultural group (N =21) and the Intra-cultural group (N = 21) were compared. Learners in each group completed five tasks over a period of five weeks in their respective groups. The tasks were then repeated over another five-week period, during which time, the Intra-cultural group continued to perform the tasks with a Japanese interlocutor, while the Inter-cultural group performed tasks with an international (non-Japanese) interlocutor. In order to provide a comprehensive examination of the effect of inter-cultural contact, this study adopted a process-product approach, which required dividing the research into multiple components. The first research component is product-oriented in that it looked at changes in learners’ motivational states due to inter-cultural and intra-cultural contact. Drawing on Dörnyei’s (2005, 2009) L2 motivational Self System and Yashima’s (2002, 2009, 2013) International Posture, this investigation took the form of a between-groups design with pre- and post-questionnaire data. In addition to the Inter- and Intra-cultural groups, a Comparison group (N = 21) was used to determine the differential effects of intra- and inter-cultural contact. Results show that intercultural contact led to significant increases in the variables L2 learning experience and international posture, with no significant change in scores for any variables in either the Intra-cultural or Comparison group. Thus, one result of inter-cultural contact in the classroom is an improvement in students’ attitudes towards the classroom environment and a gain in attitudes towards the international community. The second research component looked at the effect of inter-cultural contact on motivation from a process-level perspective. Using the construct of motivational flow (Csikszentmihalyi, 1975, 1988, 1990, 1997), this part of the thesis investigated the flow states of learners during task performances. A motivational flow questionnaire measured whether interaction arising from inter-cultural contact affected learners’ flow. Learner diaries were used to examine the ways in which flow manifested in each group. Results from questionnaire data revealed that the Inter-cultural contact group had a non-significant increase in flow scores due to the treatment, while the Intra-cultural group significantly decreased their flow scores. Thus, inter-cultural contact had a positive effect on flow in that it helped learners to overcome the negative impact of task repetition. In addition to supporting the questionnaire results, a content analysis of learner diaries revealed six components of learners’ flow. Of these, inter-cultural contact seemed to heighten flow through a sense of accomplishment, which learners associated with an increase in L2 self-confidence. The third research component examined process-features of inter-cultural and intra-cultural task interaction using the framework of language-related episodes (LREs). Transcripts of audio-recorded interactions in each group were the data used for the analysis. It was found that learners involved in inter-cultural interaction had a significantly lower word-per-turn count than intra-cultural interactions, indicating an increased level of task engagement or interactivity. A correlational analysis revealed that motivational flow is positively related to the number of turns a learner took to complete the tasks. Inter-cultural interaction generated more than twice as many LREs than in intra-cultural interactions, which included proportionately more complex LREs, more grammatical LREs, and proportionately fewer LREs that were incorrectly resolved than during intra-cultural interaction. Finally, the last research component had a process-product orientation in that it examined the effect of inter-cultural contact on the relationship between features of interaction and self-reported learning. Learners in both groups completed a self-reported learning chart after each task. There were no significant differences in claims of learning between each group. Transcripts were used to identify claims of language learning in interaction and determine which kinds of LREs led to a language item being reported. Spelling/pronunciation LREs led to self-reported learning at higher rates than other linguistic foci while complex LREs led to more reported items than simple LREs in both groups. Items emerging from LREs that were resolved incorrectly were reported at nearly twice the rate during intra-cultural interactions than during inter-cultural interactions. The thesis concludes with a discussion of findings from each research component and how they may be related. Overall, the study indicates that inter-cultural contact can indeed be provided in Japanese EFL university classrooms and presents convincing evidence that the intercultural condition is a superior learning environment in terms of improving motivation and generating learning opportunities.

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  • From Kampong to City and Back Again: A Case Study of De-urbanisation in Malaysia

    Mohd Hussain, Nur (2015)

    Doctoral thesis
    The University of Auckland Library

    Malaysia’s significant resources of oil and gas have fuelled industrialisation that has driven rural people to urbanisation and begun to change a culture of a sustainable rural lifestyle to an unsustainable urban existence. Theories of urbanisation conclude that mankind will eventually become almost fully urbanised. However, this thesis documents the beginnings of a reverse migration; de-urbanisation. The country is de-industrialising and peak oil and gas are now in the past. However, industrialisation brought with it useful technologies and infrastructures that offer increased comfort and productivity to the returnees. As people begin to move back to their ancestral land, they are learning again to live successfully with photosynthesis rather than fossil fuel. The circumstances that allowed this to happen are unique to Malaysia. The customary land rights, the matriarchal ownership of property and the cultural tradition of migration mean that this is unlikely to be replicated in the same way elsewhere in the world. However, the story of this thesis has an important lesson for other countries (especially the developing countries) that challenges the convention that mankind will be able to continue to live indefinitely (sustainably) in a ‘planet of cities’. The method used to conduct this study involves questionnaires and semi-structured interviews with both urban migrants and returnees to villages to establish the desires, intents and reasons for future migration. Based on this data, it predicts a trend of de-urbanisation and the rate of urban-to-rural migration. To assess the impact of de-urbanisation, the capacity of rural land to absorb the returnees is assessed by an inventory of productive land available. The ability of the returnees to re-adapt is analysed by in-depth interviews with the inhabitants of a typical rural village. The sample of people for this thesis has shown both ingenuity and resilience that has been achieved by a combination of a sustainable cultural tradition with more modern technologies. Finally, the findings have illustrated the beginnings of a voluntary trend of people who have ‘voted with their feet’ to move out of urban areas and return to a subsistence livelihood that is anything but poor.

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  • Kiwifruit softening: A cell wall study

    Fullerton, Christina (2015)

    Doctoral thesis
    The University of Auckland Library

    Cell walls are important for providing structural integrity to fruit tissues during softening. While there are reports on changes relating to fruit softening in kiwifruit cell walls, this study was the first to examine two closely related genotypes of Actinidia chinensis with different softening rates, MPM (a fast softener) and ACS (a slow softener), using an integrated approach of cell wall composition analysis, enzyme activity assays, microscopy and molecular techniques. The aim was to identify whether the different softening rates between genotypes were influenced by fundamental variations in the chemistry of the cell walls, or by comparative increases or decreases of gene expression or activity of the enzymes that cause the same cell wall degradative processes to occur at different speeds. While the pectin domain of the cell wall showed several dissimilarities between MPM and ACS, the main differences observed were in the xyloglucan domain. Compared to MPM, ACS appeared to have a higher xyloglucan content in the tightly bound 4 M KOH fraction and the cell wall residue, a result supported by a higher distribution of monoclonal antibody LM15 epitopes (related to xyloglucan) in all cell types in ACS. These results suggest an increased cell wall structural integrity in ACS which may resist the changes occurring to the xyloglucan-cellulose structure in MPM. Xyloglucan-modifying enzymes also varied between MPM and ACS. MPM had a higher xyloglucan endohydrolase (XEH) activity from the unripe stage, suggesting a weakened network which might be more easily accessible to other cell wall hydrolases from early in softening. Differences in the expression patterns of xyloglucan transglycosylase/hydrolase (XTH) genes showed that several were predominantly expressed in MPM and not ACS, suggesting that different isoforms of XTH were present in these genotypes. Results showed that softening of these genotypes was indeed influenced by differences in cell wall composition, gene expression and enzyme activity. Knowledge of the cell wall components, structural properties and genes expressed during softening can be applied to identify chemical and genetic markers for breeding kiwifruit to enable early stage selection of genotypes with a preferred softening rate, giving the New Zealand kiwifruit industry a competitive edge in the global kiwifruit market.

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  • The role of the BDNF Val66Met polymorphism in synaptic plasticity and Recognition memory

    Thompson, Christopher (2014)

    Doctoral thesis
    The University of Auckland Library

    A single nucleotide polymorphism of the human BDNF gene (Val66Met) may account for much of the variation in human memory performance. BDNF may influence memory via, either a modulation of acute plasticity (i.e. LTP), or a chronic influence on developing memory systems. Not only this, but BDNF could interact with different memory types in different ways. BDNF is concentrated most heavily in the hippocampus, and therefore would be likely to have a greater effect on hippocampal dependent memory. Recognition memory involves the contribution of two distinct retrieval processes, Recollection and Familiarity. Prior research suggests that Familiarity does not depend on the hippocampus, but Recollection does. Recent evidence has shown Recollection and Familiarity are associated with distinct event-related potentials (ERP): Familiarity with an early-onset effect called the FN400; and Recollection with a later positivity called the late positive component (LPC). Recent evidence suggests the successful recognition of famous faces is dependent on the hippocampus, whilst recognising a non-famous face is not. Study 1 employed a recently developed human sensory LTP paradigm in the intact human brain, and found subjects carrying the Met allele (Val/Met and Met/Met) had significantly less LTP than Val/Val individuals. Met/Met individuals also performed significantly less well in a test of visual memory. Further, the degree of LTP was significantly correlated with the index of visual memory. Study 2 found no genotype differences in FN400 amplitude (evoked when correctly recognising a previously presented face) were found. However, Val/Val individuals generated a significantly more positive LPC when correctly identifying an old face after a period of consolidation of 24 hours. Study 3 found differences between famous and non- famous face recognition, as well as between Val homozygotes and Met carriers. Famous faces elicited significantly greater activation in the hippocampus than non-famous faces. There was greater hippocampal activation seen for Val/Val individuals. There were no clear differences in the recognition of non-famous faces. These results suggest an exclusive role of BDNF in hippocampal dependent memory, with the mechanism of this likely to be a person’s ability to display LTP.

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  • PEDOT Electrodes as Redox Mediators for Determination of Antioxidants in Beverages

    Karaosmanoglu, Hande (2014)

    Doctoral thesis
    The University of Auckland Library

    Antioxidants play important roles in food quality and the protection and the promotion of human health. The most commonly used antioxidant determination techniques are the Folin-Ciocalteu assay and HPLC analyses. However, these methods have various disadvantages such as long time requirements, low sensitivity, interfering agents etc. Cyclic voltammetry at inert electrodes is another method for antioxidant determination. Although this method is easy to apply and gives rapid results, the sensitivity of an electrode with a 1 mm dia. is not adequate to analyse antioxidants at levels present in beverages. In this study, the detection of beverage antioxidants was achieved by covering the electrode with a poly3,4-ethylenedioxythiophene (PEDOT) film, which is a conducting polymer. Polymerization was performed electrochemically with 0.1 M 3,4-ethylenedioxythiophene (EDOT) and 0.1 M lithium perchlorate in propylene carbonate (PC) using cyclic voltammetry at 1 mm dia. electrodes. Glassy carbon and gold electrodes substrates were tested and better results were obtained with the glassy carbon electrode. Polymerization was performed using different potential ranges and number of preparative cycles in order to find the optimum conditions. Green tea, catechin and epigallocatechin gallate solutions were used as test standards for system optimization. The optimum number of preparative cycles and potential range were determined to be cycling four cycles between -300 and 1200 mV vs. Ag/AgCl. Tea and coffee are among the most frequently consumed beverages, and are rich in polyphenol antioxidants. Green, black and herbal teas, different types of coffee and red wine samples, along with polyphenol standards, were tested by cyclic voltammetry using an electrochemically polymerized PEDOT-covered glassy carbon electrode. The voltammetric response of the coffee samples resembled that of chlorogenic acid, which was also determined to be the major polyphenol present by HPLC analysis. In the voltammograms of green tea, there were two oxidation peaks seen at around 200 and 300 mV (Ag/AgCl) at pH 5.5, assigned mainly to epigallocatechin gallate (EGCG). Moreover, simulation solutions of green, black teas and coffee were prepared depending on their phenolic compound profiles and were subjected to CV testing, and a similar response was obtained as with the real samples. The anodic peak area was used to estimate the total phenolic content (TPC) of the samples. When these TPC values were compared with alternative spectrophotometric assays, correlations of 0.87, 0.73 and 0.75 were obtained with the Folin-Ciocalteu, DPPH and ABTS assays, respectively. EDOT is poorly soluble in water; however, an aqueous environment was required for the next study involving an enzyme. In order to overcome this problem, two types of solutions were tested; the first one was an aqueous solution containing EDOT, LiClO4 and sodium dodecyl sulphate (SDS) and the second one had different ratios of acetonitrile/water containing EDOT and LiClO4. Polymerization was performed by cyclic voltammetry and the sensitivity of PEDOT-electrodes were compared by testing gallic acid and green tea solution, versus PEDOT prepared in propylene carbonate. The oxidation potential of EDOT decreased in the aqueous solutions compared to that in the organic solvent. Furthermore, the PEDOT electrode prepared in SDS solution system showed a higher signal for the tested antioxidants compared to electrodes prepared in acetonitrile/water solutions. In the final part of this study, an amperometric biosensor has been developed to quantify specifically the phenolic antioxidant content of beverages. Tyrosinase, which oxidizes polyphenols, was physically entrapped into PEDOT during electrochemical polymerization by a cyclic voltammetry preparation. Different CV parameters were used to find optimum conditions for enzyme entrapment and to obtain a better biosensor. The concentration of quinones formed by enzymatic reaction was determined by a constant potential application of –100 mV. Catechol was used as a model substrate. The biosensor prepared by 4 cycles in the polymerization solution containing 2 mg/mL tyrosinase gave the highest sensitivity (0.0020 μA/μM). The optimum pH and temperature of the biosensor were found to be pH 6.5 and 40 ⁰C. Enzyme kinetic studies showed that the entrapment of tyrosinase into the PEDOT film was favourable, since the Km value decreased compared to that of free enzyme. A few phenolic standards and beverages were also successfully tested with the biosensor.

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  • Soil Characterisation using Screw Driving Sounding (SDS) data

    Mirjafari Miandeh, Seyed Yasin (2016)

    Doctoral thesis
    The University of Auckland Library

    The Screw Driving Sounding (SDS) method developed in Japan is a relatively new insitu testing technique to characterise soft shallow sites, typically those required for residential house construction. An SDS machine drills a rod into the ground in several loading steps while the rod is continuously rotated. Several parameters, such as torque, load and speed of penetration, are recorded at every rotation of the rod. The SDS method has been introduced in New Zealand, and the results of its application for characterising local sites are discussed in this study. A total of 164 SDS tests were conducted in Christchurch, Wellington and Auckland to validate/adjust the methodologies originally developed based on the Japanese practice. Most of the tests were conducted at sites where cone penetration tests (CPT), standard penetration tests (SPT) and borehole logs were available; the comparison of SDS results with existing information showed that the SDS method has great potential as an in-situ testing method for classifying the soils. By compiling the SDS data from 3 different cities and comparing them with the borehole logs, a soil classification chart was generated for identifying the soil type based on SDS parameters. Also, a correlation between fines content and SDS parameters was developed and a procedure for estimating angle of internal friction of sand using SDS parameters was investigated. Furthermore, a correlation was made between the tip resistance of the CPT and the SDS data for different percentages of fines content. The relationship between the SPT N value and a SDS parameter was also proposed. This thesis also presents a methodology for identifying the liquefiable layers of soil using SDS data. SDS tests were performed in both liquefied and non-liquefied areas in Christchurch to find a representative parameter and relationship for predicting the liquefaction potential of soil. Plots were drawn of the cyclic shear stress ratios (CSR) induced by the earthquakes and the corresponding energy of penetration during SDS tests. By identifying liquefied or unliquefied layers using three different popular CPT-based methods, boundary lines corresponding to the various probabilities of liquefaction happening were developed for different ranges of fines contents using logistic regression analysis, these could then be used for estimating the liquefaction potential of soil directly from the SDS data. Finally, the drilling process involved in screw driving sounding was simulated using Abaqus software. Analysis results proved that the model successfully captured the drilling process of the SDS machine in sand. In addition, a chart to predict peak friction angles of sandy sites based on measured SDS parameters for various vertical effective stresses was formulated. As a simple, fast and economical test, the SDS method can be a reliable alternative insitu test for soil and site characterisation, especially for residential house construction.

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  • Assessing Pre-Tensioned Reinforcement Corrosion within the New Zealand Concrete Bridge Stock

    Rogers, Rhys (2016)

    Doctoral thesis
    The University of Auckland Library

    Precast pre-tensioned concrete bridge construction became common in New Zealand in the 1950s and a large number of pre-tensioned concrete bridges were constructed between 1953 and 1980. These bridges do not meet today’s durability requirements and as such many are at risk of chloride induced pre-tensioned reinforcement corrosion. This deterioration can be difficult to detect and has immediate structural implications, so identification of at-risk structures is critical for bridges to achieve their required service lives. This study aimed to expand on previous research into the deterioration of pre-tensioned I-Beam bridges, to obtain an accurate assessment of the severity, prevalence and distribution of corrosion risk to all of New Zealand’s pre-tensioned prestressed concrete bridge assets. The NZ State Highway pre-tensioned bridge stock was analysed, and pre-tensioned bridges were categorised by construction era and beam type. The number of bridges in each category was assessed, and standard drawings and typical details are presented for common bridge types in New Zealand. A computer based distribution and exposure classification tool was developed that draws from international best practice asset management techniques and allows remote assessment of both individual bridges, and of the bridge stock as a whole. The exposure classification of each pre-tensioned concrete bridge on the State Highway network was remotely estimated using the tool, and these results were used to further categorise the bridge stock. A representative sample of 30 bridges was selected and subjected to a non-destructive testing regime. Trends identified in the inspections were applied back to the other bridges using the construction eras and beam types identified in this thesis. A key objective of this study was to identify pre-tensioned bridges in the wider bridge stock that were likely to be at risk of chloride induced corrosion, and recommend that they each be subjected to more thorough investigations to quantify and manage the corrosion risk to each structure. The tools developed in this thesis were intended to be used by asset managers and bridge inspectors in future assessments of New Zealand pre-tensioned bridges. The construction eras and beam types developed can be used to identify standard bridge plans and other design documents relevant to a given bridge, and to quickly discern general information about the structure. The distribution and exposure classification tool can be used to remotely assess bridges using road level and satellite photography. This thesis provided insight into the condition and durability of the New Zealand pre-tensioned concrete bridge stock. It is anticipated that the information presented will be used to identify at-risk bridges nationwide so that inspection schedules and mitigation or remediation works can be designed and performed effectively.

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  • Development of a Novel Drug Delivery System to Enhance the Oral Bioavailability of Lactoferrin

    Yao, Xudong (2015)

    Doctoral thesis
    The University of Auckland Library

    Background and objectives: Bovine lactoferrin (bLf) is a therapeutic protein that occurs naturally in cow’s milk. In recent years, there has been considerable interest to develop a bLf nutraceutical product for improvement of general wellbeing, especially with respect to improving immune responses due to its superior source of iron and antibacterial properties. However, the bioavailability of orally administered bLf is extremely low due to biochemical and physical barriers, including gastrointestinal proteases, the epithelial barrier of the small intestine and efflux pumps. Even after bLf is absorbed, another potential ‘barrier’ to take into account is that of avoiding intracellular lysosome degradation in order to reach blood supply. To achieve its therapeutic effects, encapsulation of bLf via liposomes or solid lipid particles (SLPs) has many advantages to accomplish the requirements in oral delivery. This study aims to design these lipid based systems and to evaluate their influence on the effective delivery of bLf. Methods: bLf loaded liposomes and SLPs were prepared by reverse phase evaporation (REV) method and emulsion/solvent evaporation method, respectively. Surface modification and biopolymer coating by chitosan and pectin were further applied to develop these particles with enhanced mucoadhesive properties and sustained release profile. The physio-chemical properties of mucoadhesive polymer coated liposomes and SLPs including particle size, encapsulation efficiency (EE), zeta potential, polydispersity index (PDI), drug-lipid-polymer interactions and stability against enzymatic degradation were measured as a comparison. The cytotoxicity, the cellular uptake and transport mechanisms were investigated for the optimum formulation using Colon adenocarcinoma (Caco-2) cells. Pharmacokinetic parameters associated with different formulations were determined using an in vivo rat tail vein model. Results and discussion: Particle size of optimized polymer coated liposome and SLPs were determined as from 429.6 to 740.2 nm or from 459.5 to 518.5 nm, respectively, depending on the polymer type. The drug EE of mucoadhesive SLPs was 92.02% higher than that of liposomes. SEM and TEM confirmed that hydrophilic polymer chains not only gathered around the globular surface of these lipid particles forming the coating layer, but also attached on particles forming self-assembling polymer-particle networks. Differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) revealed that bLf was presented in SLPs in an amorphous state and no interactions among drug-lipid-polymer were observed, whereas bLf may insert into liposomal membrane. Compared with liposomes, polymer coated SLPs exhibited better physical stability against aggregation induced by pH change, high temperature and high electrolyte concentration. Up to 83.67% of bLf remained in polymer coated SLPs after 6 hours (hr) digestion in rat luminal extract. ~ 30-40% of bLf can be retained in SLPs formulations over long term storage of 180 days. Moreover, SLPs formulations were less susceptible to lipolysis than liposomes, as cleaving into low amounts (~ 12%) of free fatty acids (FFA) in simulated intestinal fluids (SIF). Owing to the benefits above, SLPs were further studied at the level of the cell. Polymer coated SLPs showed biocompatibility towards Caco-2 cells up to 300 μg/mL for 8 hr. In vitro uptake of SLPs was time -, temperature - and concentration - dependent, suggesting the particles were taken up by endocytosis. Polymer coated SLPs, particularly chitosan, increased cellular uptake (~ 19%) and transport rate (~ 136.9%) of bLf across the Caco-2 cells. In vivo studies, chitosan coated SLPs also proved to be the most effective carrier in ehancing the oral bioavailability of bLf as relative bioavailability (Fbio) increased 2.69-fold in comparison to liposomes (up to 2.24-fold) and free bLf as the control. Conclusion: The project has demonstrated that the developed mucoadhesive polymer coated liposomes and SLPs were able to improve the physio-chemical stability of bLf; impart an absorption ehnacing effect in the Caco-2 cells, hence increase the oral bioavailability of bLf in rat models. The research also highlighted mucoadhesive SLPs were superior to mucoadhesive liposomes, and possess promising features for its future applications as a potential oral delivery system for therapeutic proteins and peptides.

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  • Green Infrastructure and Urban Liveability: Measuring Accessibility and Equity

    Ma, Jing (2016)

    Doctoral thesis
    The University of Auckland Library

    The purpose of this research is to gain a better understanding of the accessibility and equity levels of green infrastructure. Previous studies of green infrastructure, which have focused on stormwater management, habitat protection and ecological system conservation, do not provide a full understanding of the social functions in considering the quality of facilities and provision of green infrastructure elements. By analysing the quality and distribution of green infrastructure, this research tested green infrastructure accessibility and accessibility-based equity levels and suggested ways to improve green infrastructure access. To achieve the research goals, this research employed Network Analysis Tool from Geographic Information Systems (GIS) to measure green infrastructure accessibility. A total number of 338 green infrastructure elements in central Auckland have been selected and used in this research. These 338 green infrastructure (GI) elements include Public Garden (area30,000 square metres), taking New Zealand Recreation Association (NZRA) as a reference. In terms of quality, 338 green infrastructure elements have been classified as ‘no facility’, ‘active facility’, ‘passive facility’, and ‘active and passive facility’. The research then evaluated the accessible levels of green infrastructure to residents within three specified walking distances (400 metres, which is 5 minutes’ walk, 800 metres, which is 10 minutes’ walk, and 1,200 metres, which is 15 minutes’ walk), based on Accessible Natural Greenspace Standards (ANGSt), considering the facility conditions. By using the data of the best accessibility level (400 metres), the equity levels were tested in combination with New Zealand 2013 Census data, including age groups, ethnic groups, and income groups. Through the analysis, the research found that 338 green infrastructure elements almost cover all of the study area within 15 minutes’ walking distance. This is due to the fact that Auckland has a large amount of green infrastructure. The best areas to get access to green infrastructure in five minutes’ walk are the Western and Middle areas, then the Southern area. The CBD and the Eastern area are the poorest areas for accessible green infrastructure. In regard to the facilities inside green infrastructure, almost half of Neighbourhood GI has no facilities. The Eastern, the Southern and the Western areas are also the places without efficient facilities, which need to be considered for further improvement. The results of equity analysis show that low-income groups live with low quality green infrastructure. However, some high-income Europeans also live with insufficient green infrastructure in the Western area. Based on these findings, this research made conclusions about the analysis and the recommendations to enhance the physical accessibility of green infrastructure; such as installing suitable amenities according to green infrastructure size, building more pedestrian crossings and green networks, and developing the maintenance work of green infrastructure.

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  • “Happy in my own skin”: Filipina migrants’ embodiment of ageing in New Zealand

    Ong, Michelle Wang Hung Hung (2015)

    Doctoral thesis
    The University of Auckland Library

    Ageing Filipina migrants in New Zealand present a valuable opportunity for investigating how intersecting lines of power around ageing and migration produce both oppression and opportunities for resistance and subversion. Ageing bodies present a challenge to neoliberal idealisations of migrants and ageing persons who are required to be productive, responsible, and self-reliant. In this study I explore meaning-making around the ageing migrant Filipina’s body and trace the links between individual level meaning-making and power configurations at the socio-cultural level. I investigate how discourses of the body, revealed in women’s talk, reflect dominant structures of power around gender, age, migrant status, inter alia, and support a series of moral, ideological, and practical positions that have implications for the material body as well as subjectivity. I utilise a methodological framework that brings together feminist psychology, indigenous Filipino psychology and a poststructuralist approach to language. Applying thematic analysis on transcripts of conversations with the 20 participants, I systematically organised and identified discursive themes in the text. The four analytic chapters are organised around four areas that the participants’ stories tended to focus on. The first two are about the two forms of labour bodies are able to provide – productive and reproductive work; and the next two are about two aspects of the physical body – beauty and health. These four form the basis upon which the value of the ageing women and their bodies are measured; they are judged positively based on their ability to continue contributing to society through their engagement in productive work and provision of free care work, their maintenance of a particular standard of appearance that is desirable and that conveys a continued interest in social participation, and good health that prevents them from becoming a public burden. In conclusion I find that ageing Filipina migrants are called on to construct narratives of success in migration through their bodies, that ageing migrants’ bodies are constructed as producers, commodities, and consumers, that neoliberalism is encouraging new forms of ageism and sexism to flourish, and that participants struggle for positive identities through the use of various material and discursive strategies.

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  • United States Promotion of GM Foods in Mexico: An Application of a Public Diplomacy Model

    Martinez Pantoja, Yadira (2016)

    Doctoral thesis
    The University of Auckland Library

    The Mexican government’s policy of genetically modified (GM) foods has moved from a precautionary approach to the promotion and commercialization of agricultural biotechnology, possibly at the risk of narrowing Mexico’s biodiversity. The approval of the Law of Biosafety of Genetically Modified Organisms in 2005 allowed the cultivation of GM food crops. Subsequently, in accordance with the North America Free Trade Agreement, Mexico liberalized all agricultural product imports, including GM foods in 2008. In this thesis, I argue that the GM food policy change in Mexico can be explained by studying the US diplomatic and commercial efforts to promote GM foods. How US agencies, biotechnology companies, and NGOs have interacted with Mexican officials and other stakeholders, and how they have influenced this change of GM food policy, will be analyzed at length in this thesis. Through an adaptation of a public diplomacy model, and the conduct of documentary analysis and in-depth interviews, in this thesis I examine the state and non-state actors along with the public diplomacy activities involved in the Mexico’s GM food policy change. I describe how state actors such as the US Department of State and the Department of Agriculture have implemented programs that promote American agricultural products, including GM foods, and have applied diplomatic instruments, which in parallel with biotechnology corporations’ initiatives, appear to have been effective in influencing Mexican policy-makers. Non-state actors such as biotechnology companies and non-governmental organizations (NGOs) have also played important roles in changing Mexico’s GM food policy. My research found that biotechnology companies, as a result of their greater resources, have been more influential than NGOs, but NGO participation in public diplomacy activities has been relevant in raising GM food awareness among general audiences that in turn influenced policy-makers to exercise caution. Nevertheless, it is hypothesized that while the decision to liberalize GM food imports was a Mexican government decision, Mexican officials and legislators were influenced in that decision by US agencies and biotechnology corporations’ representations. How that influence was initiated, manifested, institutionalized, and received, analyzed by this author through the lens of a public diplomacy model, is the subject of this thesis.

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  • “Coconut water in a Coca Cola bottle” : in search of an identity: a New Zealand-born Samoan Christian in a globalized world

    Pouono, Terry (2016)

    Doctoral thesis
    The University of Auckland Library

    ‘Coconut water in a Coca Cola bottle’ symbolizes a human reality, that is, the search for identity of a New Zealand-born Samoan in the Congregational Christian Church Samoa (CCCS). The context of our investigation is the diaspora Samoan church in New Zealand. In the investigation of the concept of teu le vā, which simply means preserving harmony within the traditional, intra-cultural understandings of relational spaces; my contention is that traditional understandings of teu le vā mask the concrete reality that certain spaces and relationships within the Congregational Christian Church Samoa (CCCS) are suppressed. As reflected in the title of the thesis ‘Coconut water in a Coca Cola bottle,’ this thesis identifies one of the predicaments illustrated by the image, that is, the New Zealand-born generations being caught in between two socio-cultural worlds, namely, the Samoan and the Western world. By utilizing the research methodology ‘teu le vā intra-cultural hermeneutics,’ I will investigate the different responses of New Zealand-born generations to the socio-cultural dilemma of being suppressed between the vā, or spaces within the CCCS. This thesis also addresses how the integration of sacred relationships associated with the Samoan cultural beliefs have been integrated into a Samoan theology that has influenced church practices and belief systems. My teu le vā intra-cultural hermeneutic investigates how the preserving and perpetuating of key elements associated with the Samoan church in New Zealand, contributes to social, economic injustice within teu le vā relationships. This research also examines the impact of globalization in enforcing global concepts of culture on local cultures and contextual theologies, more specifically with respect to the CCCS. My contention is that identities associated with the local theologies are becoming increasingly ambiguous as a result of intensified intercultural interactions with the global world. This thesis is an initial exploration of the question, ‘Should the coconut water, which symbolizes the Samoan Christian identity, be preserved?’ This connects with another question: ‘Should the CCCS in New Zealand adopt a new perspective in order to be an authentic Christian witness in the global world?’ The task of seeking possible solutions to these questions leads into critical conversations for the Christian mission of the CCCS, as she strives to make the gospel message a living reality in an increasingly complex world.

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  • Nonlinear Techniques for Optical Wavelength Conversion

    Provo, Richard (2010)

    Doctoral thesis
    The University of Auckland Library

    This thesis describes the studies performed for the implementation and characterisation of various nonlinear optical wavelength conversion techniques. The experimental work presented within this thesis is accompanied by discussion of the practical considerations necessary for the successful implementation of the nonlinear wavelength conversion techniques described. The primary focus of this thesis and the largest body of experimental research is on the experimental characterisation of the four wave mixing effect of Bragg Scattering in optical fibers. Experimental and numerical characterisations of this process have been performed. The studies have enabled the phase matching condition, conversion efficiencies and bandwidth to be measured for this effect in a highly nonlinear fiber. The phase matching curve has been measured for two fibers with opposite sign β4 dispersion coefficients and an experimental implementation of a transparent high-speed optical switch based on this effect has also been demonstrated for the first time. The interfering effects of competing nonlinear processes have been investigated and the impact of zero dispersion wavelength fluctuations have been studied. Additionally this process has been used to recover the dispersion parameters for two highly nonlinear fibers and the error free transmission of a 10Gb/s data signal over 33nm has demonstrated. The four wave mixing effect of Bragg Scattering has also been investigated in the active medium of nonlinear semiconductor optical amplifiers. Several experimental procedures are outlined for the use of this effect for wavelength conversion applications. A direct experimental comparison has been performed between Bragg Scattering and Modulation Instability for wavelength conversion of data signals in these devices with Bragg Scattering demonstrating an improved performance over the single pump process. Bragg Scattering has been used to effect the wavelength conversion of both multiple data channels and high speed data signals. Two 10Gb/s data channels spaced at both 50 and 100GHz were successfully converted and single channel conversion was demonstrated at speeds as high as 80Gb/s. The third topic investigated concerns wavelength conversion in nonlinear crystals. The construction of two 10Gb/s sources has been demonstrated for the characterisation of novel micro-structured plastic fibers. Sum frequency and second harmonic generation were both used for the generation of a 10Gb/s source in the visible. This source was used to demonstrate the first successful transmission of a 10Gb/s data signal through a micro-structured polymer optical fiber.

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  • Synthetic Studies Towards Phorbaketal A

    Hubert, Jonathan (2014)

    Doctoral thesis
    The University of Auckland Library

    Phorbaketal A (6) is a sesterterpenoid natural product isolated from a Phorbas sea sponge, collected off the coast of Gageo Island, South Korea. 6 is a prototypical member of the structurally related phorbaketal and alotaketal families of natural products, which exhibit a broad range of biological activity including activation of osteoblast differentiation, inhibition of adipogenic differentiation and activation of the cAMP signalling pathway. This thesis describes synthetic endeavours towards phorbaketal A (6), with the view that the methodology established would be applicable to other members of the phorbaketal and alotaketal families. Several synthetic approaches were explored in this work for the construction of the core framework of phorbaketal A (6). Advanced epoxy-spiroketal 181 was identified as a key intermediate for the synthesis of 6. A Hosomi–Sakurai coupling of allylsilane 184 and acetal 185, followed by oxidative cyclisation, was the key focus in endeavours towards spiroketal 181. An alkyne coupling/gold catalysed cyclisation approach from bromide 342 and alkyne 343 was also successfully employed to construct the spiroketal core. Considerable effort was devoted to the preparation of key allylsilane intermediate 184. The attempted synthesis of 184 by derivatising carvone 56 was eventually discontinued in favour of an HWE-based approach, using an unusual benzoyl enol ether phosphonate 325 as a key intermediate. A scalable and efficient synthesis of acetal 185 was established via an intramolecular HWE reaction of phosphonate 190, with the chiral centre established using a Nagao aldol reaction to construct β- hydroxyketone 155. While the final epoxide opening step to form phorbaketal A (6) ultimately proved unsuccessful, these investigations have established a sound platform of synthetic methodology and resulted in the synthesis of key intermediates that will enable further synthetic efforts towards 6 and analogues thereof.

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  • Property Rights, Contracts, and Development: A Study of the Traditional Institutions of the Federally Administered Tribal Areas (FATA) of Pakistan

    Mohammad, Faheem (2012)

    Doctoral thesis
    The University of Auckland Library

    As a recipe to stem the tide of militancy in the region in the aftermath of 9/11, the FederallyAdministered Tribal Areas (FATA) of Pakistan received unprecedented local andinternational focus on development. This thesis argues that framed under the pressingexigencies of the „War on Terror‟, the on-going multi-billion US dollar development plan forthe region betrays insufficient understanding of the Pukhtun tribal society and side steps thereality of the traditional institutions while aiming for institutional change through exogenousmeans. The thesis highlights the perils of such a development approach in FATA‟straditional society, and, as a prerequisite for viable development, underscores the vital needfor an alternative approach, one that does not confront the traditional institutions of theregion.Towards the latter objective, the study embarks on an exploratory journey to unravel thenormative characteristics and role of the traditional informal institutions of FATA ineconomic exchange or contracts. The study attempts to reveal the hazards in exchange andhow the parties are able to stabilise their contractual relationships within the parametersdefined by the traditional institutions in order to achieve mutually beneficial gains. Guidedby a conjoint theoretical framework based on the Ostrom-Williamson governanceapproaches, the study first explores the traditional property rights regime to identify itsnormative principles and enforcement mechanisms. It then moves on to explore the dynamicsof its functioning in two contracting domains of commonly owned mineral resources(common-pool resources) and private property. The study reveals that the traditionalinstitutions are fairly robust particularly in relation to the former and thereby commercialenterprise therein holds a promise for the much desired economic turnaround of the regionwithout hazard prone exogenous measures.

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  • Policies of decentralisation in the context of armed conflict: An analysis of Colombian local autonomy

    Gonzalez Lagares, Lina (2013)

    Doctoral thesis
    The University of Auckland Library

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  • Social aspects in ancient Egyptian personal correspondence

    Thorpe, Susan (2016)

    Doctoral thesis
    The University of Auckland Library

    There has been considerable interest in ancient Egyptian letters, but the methodology of the research has resulted in a “compartmentalisation” of attention. Rather than considering a wide range of extant personal correspondence from a societal perspective across the various periods of ancient Egyptian history, the focus has been on individual letters, or on specific collections or letters within collections. This study will look at a selection of private letters from the Old Kingdom to the Twenty-first Dynasties under the topic headings of Complaints, Religious affairs and personnel, Military and police matters, Daily Life. By analysing the content, personalising the writers and recipients, indicating differences in style and modes of address, defining historical context, it will show how such private letters can provide insight into aspects of lifestyle, belief, social behaviour and the issues and customs of daily life. It will also identify any similarities and changes that may have occurred over the timeframe. This study will show the important contribution such personal correspondence can provide as a primary source of social history in ancient Egypt.

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  • A Study and Translation of T'aengniji

    Yoon, Inshil (1996)

    Doctoral thesis
    The University of Auckland Library

    T'aengniji (The Book of Choosing Settlements) is a Korean classic written by Yi Chung-hwan (1690-1756) on finding good places in Korea for scholar-gentry to live. This study consists of two parts : Part One is a study of T'aengnijiby analysing its contents, investigating the bibliographical aspects of the book and reviewing previous studies of T'aengniji . Throughout the thesis a new and more comprehensive approach is suggested for a better understanding of T'aengniji. The date of completion of the book and the original title of the book are also ascertained : T'aengniji was most prob ably written between the summers of 1750 and 1751 , and most likely under the title "Kagoji" (The Book of Habitable Places) or "Sadaebu kagocho'gi" (Record of Habitable Places for the Scholar-Gentry). While incorporating Taoism, Buddhism and other traditional Korean value systems, the most important body of thought in T'aengniji is Confucianism. T'aengniji uses geographical and historical approaches. Unlike previous geographical writings, however, it is written as an essay examining the four criteria: geomancy, livelihood, social characteristics and landscape. The inclusion of social characteristics in the criteria is unique serving as the most crucial element for Yi Chung-hwan's conclusion that there was no ideal place for scholargentry to live in Korea. Yi Chung-hwan intended to make an evaluation of the Korean scholar-gentry society through the search for a good place to live and this intention is clearly revealed in the text. Part Two is the translation of T'aengniji, except for four provinces , whose content and style are well represented in the other four provinces translated. The main aim of the translation is to introduce this Kore an classic into wider scholarships. This is the first translation of T'aengniji into a western language .

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