89,525 results

  • Reframing the EU concept of worker: Can sex-workers be workers?

    Masselot, A. (2015)


    University of Canterbury Library

    When applying European Union (EU) law, the concept of worker is an EU concept that can only be defined by the Court of Justice to assess EU rights (Case 53/81 Levin; Case 66/85 Lawrie-Blum; Case 196/87 Steyman). The Court of Justice has established in 1982 that sex-workers can be workers (Case 115 and 116/81 Adoui and Cournaille) for the purpose of free movement. Thus, where sex-work is decriminalised or regulated, sex-work can be considered to be a normal economic activity. However, in some circumstances sex-work cannot be considered “normal” work. For instance conditions for receiving welfare benefits might include applying for available jobs but could job-seekers be required to apply for an available sex-work position? Are there situations where standard employment law should not/cannot apply to sex-work (or indeed should but does not)? Are there circumstances where existing employment law needs to be adapted to serve the specific circumstances of sex-workers? For instance, some health and safety regulations might need to be adapted to reflect the health needs of these workers or the risk for violence. This paper investigates employment law in various jurisdictions including the Netherlands, Sweden and New Zealand, to map out standards and conditions of employment that can be transferred from “normal” work to sex-work and areas where sex-workers need different terms and conditions of employment or special protective measures.

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  • The application of different component schemes to predict wood pyrolysis and fire behaviour

    Wang, X.; Fleischmann, C.; Spearpoint, M.; Huang, X. (2015)

    Conference Contributions - Published
    University of Canterbury Library

    An analytical method and a genetic algorithm searching method are used to estimate the kinetic properties of wood based on the assumptions of two different multiple-component schemes. The pyrolysis model in Fire Dynamics Simulator is used to model material-scale and bench-scale experiments using the kinetic properties derived from the two methods. It is found that the use of the kinetic properties from the different methods and the different component assumptions cause slight differences in the prediction of pyrolysis behaviour for the material-scale experiments, however, no significant differences are found in the prediction of heat release rate for bench-scale experiments.

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  • A supply chain resilience maturity model

    Ahmad, R.; Vargo, J.; Pulakanam, V.; Chowdhury, M. (2015)


    University of Canterbury Library

    The concept of maturity model proposes that a process has a lifecycle, which is assessed on the basis of how the process is defined, managed, measured and transformed over time. A framework to develop supply chain (SC) resilience maturity model is proposed in this paper. This framework is based on two dimensions: supply chain resilience elements identified through previous literature, and supply chain management maturity levels defined by Lockamy III and McCormack (2004a). The SC resilience maturity model will be useful for organisations to assess their current state of supply chain resilience and also identify areas for further improvements.

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  • A Proportional-Derivative Endogenous Insulin Secretion model with an Adapted Gauss Newton Approach

    Othman, N.A.; Docherty, P.D.; Damanhuri, N.S.; Chase, J.G. (2015)

    Conference Contributions - Published
    University of Canterbury Library

    Endogenous insulin (UN) secreted by pancreatic β-cells plays a leading role in glucose homeostasis. Pathological changes in UN can enable early diagnosis of metabolic dysfunction before the emergence of type 2 diabetes. The dynamic insulin sensitivity and secretion test (DISST) is a dynamic test that is able to quantify participant-specific insulin sensitivity (SI) values and UN profiles. Like most studies, the DISST uses direct inversion of C-peptide concentration measurements to quantify a UN profile which relies on the assumption that insulin and C-peptide are equimolarly secreted from β-cells. This study develops a proportional-derivative (PD) control model that defines UN as a function of glucose concentration to provide further insight and modeling capability for this prediabetic state. Results show that individuals with normal glucose tolerance (NGT) tend to have higher gain ratio compared to individuals with impaired fasting glucose (IFG) with median values of 19.11 and 2.79 min, respectively. In particular, the main difference between the UN profiles of NGT and IFG group lies within the derivative gain (??), specifically in first phase secretion (U1). A higher value of ?? is needed in response to an abrupt increase in plasma glucose level. This proposed model offers model simplicity as well as a link between insulin secretion and glucose concentration that is able to provide more information in determining each participant’s glycemic condition.

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  • The detectability of confounding effects in glycemic diary data from in silico patients with diabetes

    Mansell, E.J.; Docherty, P.D.; Chase, J.G. (2015)

    Conference Contributions - Other
    University of Canterbury Library

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  • Braced Frame Using Asymmetrical Friction Connections (AFC)

    Chanchi Golondrino, J.; Xie, R.; MacRae, G.A.; Chase, J.G.; Rodgers, G.W.; Clifton, C. (2015)

    Conference Contributions - Published
    University of Canterbury Library

    A single storey moment resisting frame with one bay and equipped with a concentric AFC brace was tested. The asymmetrical friction connection brace (AFC brace) was assembled using one 250PFC channel, two Bisalloy 500 shims, and two M16 Grade 8.8 galvanized bolts. Results show that by introducing the AFC brace, the frame can undergo drifts up to 3.0% without yielding any frame member or component, and more importantly with low degradation on the AFC detail. Results also show that the amount of load that the frame can absorb during a seismic event can be controlled by the AFC brace strength.

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  • Pair Production Explained in a Hidden Variable Theory

    Pons, D.J.; Pons, A.D.; Pons, A.J. (2015)

    Journal Articles
    University of Canterbury Library

    Problem- Pair production is a key component of mass-energy equivalence yet the deeper processes whereby photons transform into matter-antimatter pairs are unknown. Purpose- A theory is presented for the mechanics of pair production at the fundamental level. Approach- Physical realism was accepted at the outset. A theory was developed comprising internal structures (hidden variables) and discrete fields, called the Cordus theory. Logical inference was used to determine the mechanics for pair production under these assumptions. Findings- Particles are found to be defined by their field emissions, with rearrangement of those fields changing the particle’s identity. The process mechanics are extracted from the theory, and successfully applied to explain remanufacture of the evanescent discrete fields of the photon into the electric fields of the electron and antielectron. The mechanics also explains recoil dependency on photon polarisation. Surprisingly, it also provides a physically natural explanation for electron holes. Originality- The ability to set out a mechanics for pair production at the foundational level is a novel advancement, as is the ability to explain in a physically natural way why the causality involves angular orientations of the inputs (polarisation) and outputs (recoil). There is further novelty in achieving this from the non-local hidden-variable sector of physics. Implications- Annihilation, which is the inverse process, has also been demonstrated within this same framework. An ontological explanation for mass-energy equivalence is now available by assuming physical realism and that particles have internal structures. These explanations are logically consistent with the rest of the Cordus theory for other phenomena. The hidden-variable sector is shown to have yielded an alternative theory of fundamental physics with excellent explanatory power under physical realism. It provides novel insights into processes at the next deeper level of physics, and shows a candidate route to a new physics.

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  • Research Engagement after Disasters: Research Coordination Before, During, and after the 2010-2011 Canterbury Earthquake Sequence, New Zealand

    Beaven, S.; Wilson, T.M.; Johnston, L.C.; Johnston, D.M.; Smith, R.T. (2015)

    Journal Articles
    University of Canterbury Library

    This article argues that active coordination of research engagement after disasters has the potential to maximize research opportunities, improve research quality, increase end-user engagement, and manage escalating research activity to mitigate ethical risks posed to impacted populations. The focus is on the coordination of research activity after the 22nd February 2011 Mw6.2 Christchurch earthquake by the then newly-formed national research consortium, the Natural Hazards Research Platform, which included a social science research moratorium during the declared state of national emergency. Decisions defining this organisation’s functional and structural parameters are analyzed to identify lessons concerning the need for systematic approaches to the management of post disaster research, in collaboration with the response effort. Other lessons include the importance of involving an existing, broadly-based research consortium, ensuring that this consortium's coordination role is fully integrated into emergency management structures, and ensuring that all aspects of decision-making processes are transparent and easily accessed.

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  • Shapes and landscapes - a morphological approach to the meta-population dynamics of a galaxiid

    Egan, E.M.; Hickford, M.J.H.; Quinn, J.M.; Schiel, D.R. (2015)

    Conference Contributions - Other
    University of Canterbury Library

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  • How has gambling become normalised in New Zealand?

    Mack, Hugh Jonathan Devereux (2015)

    Masters thesis
    University of Canterbury Library

    This study investigated the normalisation of gambling within the New Zealand context to explore whether an ausugenic environment exists, using qualitative interviews in combination with a self-ethnography. An ausugenic environment is one where gambling has become embedded in the cultural attitudes and behaviour of a society to the extent that it is no longer considered to be an abnormal or noteworthy activity. In order to investigate this two phases of qualitative interviews were conducted with the first being with members of the public who were also asked to record a diary of gambling related things they noticed over the course of a weekend. To better understand the results for diary participant responses, the researcher underwent the same diary keeping process during the same weekend while also revisiting locations described by the participants to validate their reports. The second phase involved interviews with counsellors from the Problem Gambling Foundation of New Zealand to explore their attitudes towards gambling and experiences that their clients who were most affected by gambling in New Zealand. The outcomes of this research were two conceptual models that propose how individuals normalise gambling behaviour personally as well as how society both creates and perpetuates an ausugenic environment. This study also discusses the concept of environmental normalisation as a development upon advertising wearout theory. It suggests that individuals may become blind to attitudes and stimuli within their environment after prolonged periods of exposure through many different sources. The idea that this may be not simply something that advertisers seek to avoid as is classically thought, but implemented as a deliberate strategy for organisations seeking to gain wide acceptance of their product or service is also proposed. The study ten seeks to make significant contributions towards the betterment of society through use of the findings to recommend policy alterations the New Zealand Government should implement and suggest alternative ways that the treatment of problem gambling is addressed in future.

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  • Climate- and habitat-mediation of predator-prey interactions in an invasion context

    Hunt, Sophia Katherine (2015)

    Masters thesis
    University of Canterbury Library

    Ecosystems across the globe are facing a range of anthropogenically-driven changes, including biotic invasions, urbanisation and land-use alterations, which can affect ecosystem structure and stability. To manage both native species decline and invasive species spread it is imperative that we can accurately predict how current global environmental change will affect biotic communities. I examined effects of different land uses at both landscape- and habitat-scales on native (Culex pervigilans) and exotic (Aedes notoscriptus) mosquito distributions in lentic (standing water) freshwater habitats. Because of the importance of land use on habitat characteristics, I expected different land uses would contain different biotic communities, and that mosquitoes would more likely be present in simple communities with fewer predators. Moreover, because habitat disturbance and modification can significantly influence community structure, I expected less diverse pond communities in habitats within highly modified urban and pasture land uses would also be more likely to contain mosquitoes. I found land use affects mosquito presence, and was likely strongly linked with land-use effects on predator presence and taxon richness. Predators were more common in habitats within native forest and tussock grassland, and mosquitoes were almost entirely restricted to urban and pasture habitats. Moreover, local habitat characteristics had a strong influence on both mosquito and predator presence, with deeper and more open habitats supporting greater predator abundance, thereby excluding mosquito larvae. To further investigate the global of climate change on predator-prey interactions involving Ae. notoscriptus and Cx. pervigilans, I conducted two experiments. Firstly, I measured effects of habitat warming and short- and long-term habitat drying on interactions between the two mosquito species and three predatory invertebrates, Anisops wakefieldi backswimmers, Austrolestes colensonis damselflies, and Procordulia smithii dragonflies, which represented predators characteristic of different habitat drying regimes. A second experiment further tested interactions between A. wakefieldi and the two mosquito species in a wider range of temperatures. There was little evidence that short-term habitat drying affected interaction strengths of any of the predator-prey combinations, but strong evidence for the importance of temperature-mediated predation rates which depended on both predator and prey identities. Here, predators characteristic of more temporary hydroperiods showed temperature-mediated predation responses on the two mosquito species: increasing temperature resulted in greater predation on native Cx. pervigilans but not effect on predation on exotic Ae. notoscriptus. The second experiment revealed, again, that predation depended on both temperature and mosquito species with higher predation occurring at increased temperature, but also indicated life history traits could mediate the overall effect of temperature-mediated predation. Overall, I have shown that interactions between temperature, predator identity and mosquito species will be very important in determining the potential for mosquitoes to invade under a changing climate. Considering effects of both climate change and land-use-driven habitat modification on the invasion potential of mosquitoes in freshwater communities will therefore be important for managing both native species decline and spread of invaders. Moreover, research and management decisions on critical species like mosquitoes will need to encompass multiple drivers of climate change at both global and local scales.

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  • Estimation of individual tree metrics using structure-from-motion photogrammetry.

    Miller, Jordan Mitchell (2015)

    Masters thesis
    University of Canterbury Library

    The deficiencies of traditional dendrometry mean improvements in methods of tree mensuration are necessary in order to obtain accurate tree metrics for applications such as resource appraisal, and biophysical and ecological modelling. This thesis tests the potential of SfM-MVS (Structure-fromMotion with Multi-View Stereo-photogrammetry) using the software package PhotoScan Professional, for accurately determining linear (2D) and volumetric (3D) tree metrics. SfM is a remote sensing technique, in which the 3D position of objects is calculated from a series of photographs, resulting in a 3D point cloud model. Unlike other photogrammetric techniques, SfM requires no control points or camera calibration. The MVS component of model reconstruction generates a mesh surface based on the structure of the SfM point cloud. The study was divided into two research components, for which two different groups of study trees were used: 1) 30 small, potted ‘nursery’ trees (mean height 2.98 m), for which exact measurements could be made and field settings could be modified, and; 2) 35 mature ‘landscape’ trees (mean height 8.6 m) located in parks and reserves in urban areas around the South Island, New Zealand, for which field settings could not be modified. The first component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which 2D (height, crown spread, crown depth, stem diameter) and 3D (volume) tree metrics could be estimated. Each of the 30 nursery trees was photographed and measured with traditional dendrometry to obtain ground truth values with which to evaluate against SfM-MVS estimates. The trees were destructively sampled by way of xylometry, in order to obtain true volume values. The RMSE for SfM-MVS estimates of linear tree metrics ranged between 2.6% and 20.7%, and between 12.3% and 47.5% for volumetric tree metrics. Tree stems were reconstructed very well though slender stems and branches were reconstructed poorly. The second component of research tested the ability of SfM-MVS to reconstruct spatially-accurate 3D models from which height and DBH could be estimated. Each of the 35 landscape trees, which varied in height and species, were photographed, and ground truth values were obtained to evaluate against SfM-MVS estimates. As well as this, each photoset was thinned to find the minimum number of images required to achieve total image alignment in PhotoScan and produce an SfM point cloud (minimum photoset), from which 2D metrics could be estimated. The height and DBH were estimated by SfM-MVS from the complete photosets with RMSE of 6.2% and 5.6% respectively. The height and DBH were estimated from the minimum photosets with RMSE of 9.3% and 7.4% respectively. The minimum number of images required to achieve total alignment was between 20 and 50. There does not appear to be a correlation between the minimum number of images required for alignment and the error in the estimates of height or DBH (R2 =0.001 and 0.09 respectively). Tree height does not appear to affect the minimum number of images required for image alignment (R 2 =0.08).

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  • An isotopic and anionic study of the hydrologic connectivity between the Waimakariri River and the Avon River, Christchurch, New Zealand

    Tutbury, Ryan William Owen (2015)

    Masters thesis
    University of Canterbury Library

    The Waimakariri-Avon River system is an important component of the Christchurch aquifer system and has been identified as one of, if not the, primary groundwater flow path. The Waimakariri-Avon River system is ideally suited to geochemical tracing of surface water- groundwater interaction and while many past studies have been undertaken to characterise this system, in terms of its geochemistry and physical hydrogeological components, there is still a large amount of uncertainty as to how long it takes for groundwater to flow from the Waimakariri River, through the Waimakariri-Avon River groundwater system, to the springs that feed the Avon River. The primary goals of this thesis were to; 1) Constrain the residence time of groundwater connecting the Waimakariri-Avon River groundwater system using stable oxygen and hydrogen isotopes and analysis of anionic concentrations of: chloride, fluoride, nitrate, nitrite, bromide and sulfate, 2) Provide additional evidence of a hydrological connection between the Waimakariri River and the Avon River systems, 3) Present observations of the stable isotopic and anionic response of surface water to rainfall events, 4) Identify stable isotopic and anionic surface water variation along the Waimakariri-Avon River system, and establish the reasons for these. This study presents the use of natural isotopic and anionic tracers to characterise the residence time of the groundwater that flows between the Waimakariri and Avon Rivers, by sampling surface water and meteoric water at sites that are part of the Waimakariri-Avon River system. 375 samples were collected from 10 surface water and 4 rainwater sites distributed across the Waimakariri-Avon River surface water-groundwater flow path between March 5th and August, 2014. Additionally the study provides further stable isotopic evidence of the connection between the Waimakariri and Avon Rivers, as well as presents the variability of surface water chemistry in response to rainfall events. Identification of isotopic and anionic variation along the Waimakariri-Avon River system, by surface water sampling, was also conducted to establish the probable causes of observed variations. This study found that the use of large rainfall events, as natural tracers, was not conclusive in establishing the groundwater residence time of the Waimakariri-Avon River system within the 4.5 month sampling period available. Surface water sampling provided further evidence in support of past studies that have determined an isotopic connection between the Waimakariri River and the Avon River with mean stable isotopic values for the Waimakariri River (-8.85‰ δ18O and-60.65 δD) and Avon River (-8.53‰ δ18O and -58.72 δD) being more similar than those of locally derived meteoric water (-5.48‰ δ18O and -35.13 δD). Observations of surface water chemistry variations thorough time determined and identified clear responses to rainfall events as deviations from baseline values, coinciding with rainfall events. Isotopic variation along the Waimakariri-Avon River system was shown to reflect Waimakariri River derived shallow groundwater with the contributions from rainwater increasing with increased proximity to the Avon River mouth. Anionic profiling of the Waimakariri-Avon River system identified increasing concentrations of chloride, nitrate, sulfate, nitrite and bromide, relative to the Waimakariri River, with increased proximity to the Avon River mouth. Fluoride concentrations were identified in lower concentration, relative to the Waimakariri River, with increased proximity to the Avon River mouth. Fluoride and nitrite concentrations were attributed predominantly, if not entirely, to an atmospheric source as mean concentrations were greater in meteoric waters by a factor of at least 2, compared to surface water samples. Chloride and bromide have been attributed to possible salt water mixing as a result of the interaction of upwelling deeper groundwater with the marine and estuarine sands beneath the upper unconfined aquifer, that act as a confining layer within the Christchurch aquifer system. Nitrate and sulfate concentrations have been attributed to potential fertilizer usage and past land-use impacts. A significant step-change increase in chloride, bromide, nitrate and sulfate concentrations was observed between the surface water sample sites at Avonhead Park and the University of Canterbury. The step-change coincides with the boundary of the upper confining layer within the Christchurch aquifer system, and explains the increases in chloride and bromide concentrations. It also suggests a widely distributed source area as concentrations do not become diluted at the Avon River site, at Hagley Park, , which would be expected from the addition of other tributaries, if they did not have similarly high chloride and bromide concentrations. The area between these two sites has also been identified by Environment Canterbury as potentially impacted by past agricultural land-use practices and may explain the increases in nitrate and sulfate concentrations.

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  • Measuring social and emotion information processing in early childhood : a pilot-test of a revised and expanded storybook interview.

    Burgess, Carly (2015)

    Masters thesis
    University of Canterbury Library

    Social information processing (SIP) models of social cognition are increasingly being applied to children and adolescents with most studies focusing on differences between aggressive and nonaggressive children in the coding and interpretation of social cues (Dodge and Newman, 1981; Darin and Sharon, 2012). However, research in this field is characterised by two substantial deficits, including insufficient integration of emotion processing in SIP frameworks and a lack of accessible and reliable measurement tools for social and emotional information processing, particularly for young children. The current study attempted to address this gap in the research by pilot-testing a revised and expanded version of the Social Information Processing Interview for preschool children (SIPI-P; Ziv and Sorongon, 2011). Fifty children (26 male and 24 female), who ranged from 41 to 61 months of age were recruited from eleven early childhood education centres in the Christchurch metropolitan area. Analyses of both qualitative and quantitative data showed a number of gender differences and distinctions in social and emotional information processing across the prosocial, ambiguous, and conflict hypothetical stories. Boys tended to score slightly better than girls across 8 of the SIP and emotion processing variables. However, boys also generated more aggressive responses than the girls. Overall, the inclusion of emotion processing variables and the two prosocial scenarios in a single interview for preschoolers (SIPI-P) is achievable, although additional revision is necessary with the prosocial hypothetical stories. Future research on the SIP model using this tool may provide a more complete picture of the development of social and emotional information processing in young children.

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  • An investigation into the surface chemistry of supported gold phosphine clusters

    Anderson, David Philip (2013)

    Doctoral thesis
    University of Canterbury Library

    This thesis describes the preparation and study of a wide range of supported gold catalysts based on atomically-precise triphenyl phosphine stabilised gold clusters. This selected range of ligand-stabilised gold clusters were prepared in attempt to study the effect of increasing cluster nuclearity on the electronic and catalytic properties of these materials. A novel far-infrared study was conducted on the pure cluster materials in attempt to understand the metal-metal and the metal–ligand vibrations, which was also compared to the simulated spectra for each cluster. The design and activation of these novel catalysts based on gold clusters was discussed and the factors that influence activity were described. A comprehensive photoelectron study of the catalysts was conducted in an attempt to understand the electronic structure of the supported gold clusters and the effect of various activation conditions have on the electronic structure of the gold clusters. A selection of the prepared supported gold catalysts were tested for their catalytic activity for the partial oxidation of styrene and the influence of the several activation conditions on the reactivity of the catalyst is also examined. In collaboration, the application of a selection of ligand-stabilised gold clusters as hydrogen sensors and as catalysts for the photocatalytic generation of hydrogen from ethanol is also investigated.

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  • Development of a novel stimuli responsive filtration membrane using self-assembling peptides.

    Ponnumallayan, Prasanna (2014)

    Doctoral thesis
    University of Canterbury Library

    Membrane based separation of specific constituents from a complex mixture is a wellestablished technology. Numerous filtration membranes have been developed for separations based on size, charge and hydrophobicity. Alternatively, synthetic membranes have been modified using various materials (e.g. charged polymers), to induce stimuli responsiveness and achieve specific separation goals. However, controlling finer separations based on more complex properties has been a challenge. Further improvements in separations could be made with a universal membrane that could be used for a wide range of applications. This thesis describes the development of a novel stimuli-responsive membrane whose pores and surface are functionalised with self-assembling peptides (SAPs). SAPs are molecules that spontaneously organize into ordered structures through non-covalent interactions, in response to external stimuli. The use of reversible SAPs to control membrane permeability could possibly result in a more effective separation process, whereby a condition such as pH could be used to enable or block passage of certain solutes through the membrane. To progress towards achieving this goal, the following sub-objectives were addressed, i) to identify a suitable reversible SAP and examine the effect of conjugating it with a poly(ethylene glycol) (PEG) polymer spacer on self-assembly, ii) to functionalise a membrane surface and subsequently tether the SAP via the spacer molecule, whilst retaining the self-assembling behaviour on the membrane surface. Initially, peptide P11-4 (QQRFEWEFEQQ) was chosen as the candidate for membrane tethering, because it can spontaneously switch molecular conformation from random coil at high pH to β sheet at low pH. P11-4 was conjugated to a 2 kDa N-hydroxy succinimideactivated PEG via N-terminal amine coupling to form P11-4-PEG-2K and the conjugation was validated using MALDI-tof spectrometry. However, P11-4-PEG-2K did not retain self-assembly of the peptide P11-4 but instead retained its random coil structure at pH < 3, in contrast to the behaviour of native P11-4, which formed β sheets at similar pH. P11-4-PEG- 2K retained its random coil conformation across various pH conditions (pH 2.5, 7 and 11) and incubation periods (2 min-20 days). Additional investigations on the effect of unreacted free PEG on P11-4 self-assembly indicated that the presence of free PEG in solution did not hinder self-assembly. Further, conjugation carried out in 3 mM sodium phosphate buffer and water also resulted in P11-4-PEG-2K that lost its ability to form β sheets at pH 2.5. Thus, P11-4-PEG-2K was deemed unsuitable for membrane modification and an alternative peptide EL-5F (ELELELELELF), with pH responsiveness, was used for further investigations on bioconjugate self-assembly in solution and upon being tethered to a membrane surface. For the first time, rapid and reversible pH-regulated self-assembly of EL-5F and its conjugates with 2 and 5 kDa PEG (EL-5F-PEG-2K and EL-5F-PEG-5K) was demonstrated. Circular dichroism indicated the formation of β sheet structures at pH < 5.9, 5.8 and 5.4 and disassembly to random coils above those pH values for EL-5F, EL-5F-PEG-2K and EL-5FPEG- 5K, respectively. β sheets were confirmed by the thioflavin T assay and transmission electron microscopy revealed the existence of extended fibrillar structures below the above pH values. pH-induced secondary structure conversion in both directions was reproducible for over fifteen cycles, even at salt concentrations of up to 200 mM NaCl, and the amounts of  sheet formed were quantitatively related to pH below the transition points. Self-supporting hydrogelation after self-assembly was observed at concentrations as low as 0.2 wt%, which is 15-fold lower than previously reported concentrations with PEGylated SAPs. Subsequent work, involving tethering of EL-5F-PEG-2K to an Anodisc alumina membrane surface and/or pores and investigations on the effect of reversible self-assembly on the permeability of the membrane was carried out. COOH groups were immobilised on the membrane surface to prepare it for the coupling of EL-5F-PEG-2K, using multilayer deposition of poly(acrylic acid) (PAA) and poly(allylamine hydrochloride) (PAH). EL-5FPEG- 2K was then successfully amine-coupled to the COOH groups on the surface and this was confirmed using ATR-FTIR. Subsequent flux tests indicated no pH-dependant variation in buffer flux properties of the EL-5F-PEG-2K modified membrane. However, MWCO experiments using 72 and 29 kDa PEGs indicated reversible self-assembly of membrane tethered EL-5F-PEG-2K, upon changes in pH, thereby affecting macromolecule permeation. Furthermore, investigations on the reversible, pH-regulated self-assembly of peptide EL-5F and conjugate EL-5F-PEG-2K tethered to polystyrene nanoparticle (NP) surfaces, showed size transitions and aggregation of NPs upon changes in pH, indicating retention of peptide and bioconjugate self-assembly after surface tethering. The results provide a tentative but consistent proof-of-concept, giving the first steps towards the development of a novel switchable SAP-based, stimuli-responsive membrane. Further investigations suggested to validate reversible peptide self-assembly on the membrane surface, are expected to pave the way towards achieving finely controlled membrane separations.

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  • Non-Core Business? An examination of university art galleries in New Zealand Aotearoa

    Baines, Penelope (2015)

    Masters thesis
    Victoria University of Wellington

    University art galleries are the most common form of campus museum in New Zealand and are increasingly viewed as alternative and innovative interdisciplinary teaching tools. Much of the literature concerning university art galleries discusses the potential of these organisations to act as forums, laboratories and portals for the presentation of diverse ideas within institutions of higher education. Yet these organisations are often overlooked by their parent organisation and considered superfluous to the university’s core business. Despite the ubiquity of university art galleries, little research has been undertaken regarding these organisations within the context of Aotearoa New Zealand. This dissertation explores this issue by examining the ways in which university art galleries have integrated themselves into their university communities. This dissertation provides a general and concise overview of university art galleries in New Zealand and then presents two in-depth case studies, examining first the Gus Fisher Gallery and then the George Fraser Gallery at the University of Auckland. By utilising a wide range of sources including international and local theoretical literature, interviews, and documentation of public programmes and exhibition histories, these two case studies demonstrate that university art galleries contribute to their parent organisation in a variety of ways. These include serving as an important public interface for the university by showcasing academic and creative scholarship undertaken by the institution’s staff, students, and alumni; acting as a vehicle through which the university can achieve strategic and academic goals and objectives, and assisting the university in fulfilling its duty to act as the “critic and conscience of society”. This dissertation makes a contribution to museum studies and current museum practice by addressing a gap in the New Zealand literature on this topic. It is the first critical academic analysis of university art galleries in this country situated in relation to British and American theory. In particular, it builds upon and refines Janet Marstine’s argument that university art galleries can lead in the development of the Post-Museum and questions whether Marstine’s theories can apply to the New Zealand context.

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  • Electrical and Magnetic Investigations of Magnesium-doped Epitaxial Gadolinium Nitride Thin Films

    Lee, Chang Min (2015)

    Masters thesis
    Victoria University of Wellington

    Mg-doped epitaxial GdN thin films with various Mg-doping levels were grown using molecular beam epitaxy, and their electric, magnetic and optoelectronic properties were investigated. Characterisation through X-ray diffraction technique showed that there is no systematic variation in the crystallographic structure of the films with increasing level of Mg-doping, for Mg concentrations up to ~5 x 10¹⁹ atoms/cm³. However, from Mg concentration ~2 x 10²⁰ atoms/cm³ a clear deterioration in the crystalline quality was seen. We observed an increase in the resistivity of the films from 0.002 Ωcm to 600 Ωcm at room temperature when increasing the Mg-doping level, resulting in semi-insulating films for Mg concentrations up to 5 x 10¹⁹ atoms/cm³. Hall effect measurements revealed that the n-type carrier concentration was reduced from 7 x 10²⁰ cm⁻³ for an undoped film to 5 x 10¹⁵ cm⁻³ for a heavily doped film, demonstrating electron compensation in GdN via Mg-doping. Magnetic measurements exhibited substantial contrasts in the films, with a Curie temperature of ~70 K for an undoped film reduced down to ~50 K for a heavily Mg-doped film. Finally, photoconductivity measurements showed that films with higher level of Mg-doping displaying a faster photoconductive response. The decay time of 13000 s for an undoped film was reduced to 170 s with a moderate level of Mg-doping, which raises the possibility of Mg impurities providing hole traps that act as recombination centres in n-type GdN films.

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  • Tourism and the environment: The response of privately owned accommodation businesses in Da Nang city, Vietnam

    Nguyen, Trang (2015)

    Masters thesis
    Victoria University of Wellington

    The purpose of the study is to investigate the response of privately-owned hospitality enterprises in Da Nang city, Vietnam to environmental concerns. The study is inspired by global growing attention to how sustainable development in general and sustainable development in the tourism industry in particular can be promoted, especially the environmental aspect. Given the vital role of the private sector in achieving sustainable development and the fact that in the context of Vietnam, the private sector is still a less powerful economic player than the state-owned sector, the study only focuses on the privately-owned hotels. The study was conducted with the aims of (i) filling in the gap of understanding of the issue in developing countries, (ii) seeing how effective the private sector’s contribution in Da Nang city and in Vietnam in general has been in promoting sustainable tourism development, and (iii) coming to suitable recommendations, based on the research results, to increase the effectiveness of the private sector in sustainable tourism development. Qualitative methodology was used. Fifteen hotel managers participated in the semi-structured interviews. Some governmental officers also joined the research to provide supplementary information. The research findings show that the hotel managers in Da Nang city generally had good understanding of relevant environmental issues in the accommodation sector and tourism industry. All hotels researched were using environmental practices but the smaller ones tended to have less practices. Noticeably, not all hotels were using obligatory practices described by laws. Reducing costs was the most chosen motivation for hotels to go green. Simultaneously, it was picked up by most participants as the biggest difficulty that prevented them from pursuing an environmental path. The research also revealed a weak collaboration between the city government and the accommodation businesses in dealing with environmental concerns.

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  • The effect of tophaceous gout on the structure and function of the Achilles tendon

    Carroll, Matthew Richard

    Doctoral thesis
    Auckland University of Technology

    Gout is the most prevalent form of inflammatory arthritis in men older than forty years of age and has a significant functional and social impact. Tophaceous gout is the most progressed phase of gout and is associated with foot pain, impairment and disability in joints (first metatarsophalangeal joint) and soft tissue (Achilles tendon). The structural characteristics of the Achilles tendon (AT) enables it to withstand the large forces imposed during the gait cycle. Any alteration to the internal structure of the AT may affect the ability of the gastro-soleus complex to generate force, transfer muscle power and absorb energy during the gait cycle. Current research has reported tophus deposition in the AT. However, there is limited information on the impact of tophus on the AT structure and the impact of gait characteristics in people with gout. Therefore, the aims of this thesis were to investigate the prevalence of ultrasound (US) lesions in the AT and the gait parameters of walking velocity, ankle power and ankle range of motion in participants with tophaceous gout compared to age and sex-matched control participants. Two systematic reviews with meta-analysis were also undertaken. The first systematic review was conducted on US lesions in the AT of people with inflammatory arthritis. The results demonstrated that the majority of studies reporting US lesions were in spondyloarthropathies, but limited data relating to tophaceous gout. The meta-analysis demonstrated the AT was significantly thicker in people with spondyloarthropathies, erosions more prevalent in both spondyloarthropathies and rheumatoid arthritis, but enthesophyte formation was not significantly more prevalent in participants with spondyloarthropathies when compared to control participants. The review highlighted inconsistencies in both defining and scoring US lesions indicative of inflammation and structural damage in people with inflammatory arthritis. The second systematic review evaluated gait parameters in inflammatory arthritis. The findings from the review identified the most commonly assessed gait parameters used to define gait adaptation in inflammatory arthritis, with the majority of studies focusing on gait adaptation in rheumatoid arthritis. The meta-analysis demonstrated significant differences in walking velocity, cadence, stride length, double support time, ankle power and forefoot plantar pressure, but no significant differences in ankle range of motion when participants with inflammatory arthritis were compared to controls. The review highlighted the wide range of methodologies used to acquire spatiotemporal, kinetic and plantar pressure gait parameters. Using a case-control study experimental design, AT structure was investigated using grey-scale and power Doppler US imaging. Gait function was evaluated using three-dimensional (3D) gait analysis. Twenty four participants with tophaceous gout with a mean (SD) age of 62 (12) years old were matched with 24 age and sex-matched control participants, with a mean (SD) age of 62 (12) years old. The majority of the participants were middle aged males (92%), predominately of European ethnicity (77%). The control participants demonstrated a significantly higher number of Europeans (p ≤ 0.01). Participants with gout had higher mean BMI compared to controls (p < 0.01). Participants with gout had well established disease of 17 years, with a mean serum urate level of 0.37 mmol/L. Comorbidities that included hypertension, cardiovascular disease and type 2 diabetes were found in approximately one-third of participants with tophaceous gout. The case participants with gout demonstrated had a higher prevalence of hypertension (p < 0.01) and cardiovascular disease (p = 0.03) compared to the control participants. The majority of participants with gout were prescribed allopurinol (n = 20, 83%). In order to investigate specific regions of the AT, the tendon was divided into three zones (insertion, pre-insertion and proximal to mid-section). US lesions were scored using a semi-qualitative scoring system. The scoring system assessed the tophus characteristics, tendon echogenicity, tendon vascularity, tendon morphology, enthesis, bursal morphology and bone profile using binary, continuous measurement and semi-qualitative scale. As lesions were nested within participants, a general estimating equation approach was used to analyse data. The results demonstrated participants with tophaceous gout showed a significantly higher prevalence of tophus deposition (p < 0.01), intratendinous hyperechoic spots (p < 0.01) and intratendinous inflammation (p < 0.01) throughout all zones of the AT. There was minimal data reporting hypoechoic areas with loss of fibrillar echotexture in the AT of both the case and control participants. These findings suggest that tophus deposition and associated inflammation in the AT may be a clinically silent process, with containment of inflammation. In the second case-control study, each participant undertook 3D gait analysis with passive lightweight markers used to track and model the lower limb in accordance with the Oxford Foot Model. Surface electromyography signals were recorded during gait from the medial gastrocnemius, lateral gastrocnemius and tibialis anterior of both limbs. Gait measures included walking velocity, double limb support time, first metatarsophalangeal joint motion, peak ankle joint force, ankle moment and power. When compared to control participants, participants with tophaceous gout demonstrated significantly decreased walking velocity (p < 0.01), with a mean difference of -0.20 m/s, and an increased double limb support time (p < 0.01), with a mean difference of 0.05s. Peak ankle joint power was reduced with a mean difference of -0.31 W/Kg (p = 0.01), but peak ankle joint force, difference of 15.6N (p = 0.25), and peak ankle joint moments, with a mean difference of 0.06 Nm/Kg (p = 0.16), were not significantly different between the two groups. Medial gastrocnemius (p = 0.04), with a mean difference of 2.7 %MVIC/s, and lateral gastrocnemius (p < 0.01), mean difference of 6.2 %MVIC/s muscle activity was increased in participants with tophaceous gout. Reductions in walking velocity in the cases were associated with alterations in cadence, step length, double support time and gait cycle time. Reductions in walking velocity were also associated with decreased ankle joint angular velocity in the people with gout. With the ankle joint moments preserved and not significantly different between the two groups, the reductions in ankle joint angular velocity explain the reduced ankle joint power output. These findings highlight the importance of walking velocity and imply that walking velocity may be the central mechanism by which the body modulates gait adaptation. The findings of the thesis are clinically relevant. When managing AT pathologies in people with tophaceous gout both structure and function must be considered. Structural integrity of the AT must be determined and the degree of gait adaptation must also be quantified to provide the clinician with a good overall perspective of functional ability. The findings are also relevant for the design of future clinical trials. The investigation of mechanical properties of the AT in people with gout is warranted. With baseline gait adaptations quantified, the impact of non-surgical interventions such as footwear, foot orthoses and strength training must also be considered for their ability to alter the process of gait adaptation in people with gout.

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