82,974 results

  • COMMD10 Regulates Protein Trafficking

    Ware, Adam William (2017)

    Doctoral thesis
    University of Otago

    The epithelial sodium channel (ENaC) is a heterotrimeric, amiloride-sensitive Na+ channel located at the plasma membrane of various tissues, including kidneys and the vasculature. ENaC abundance and activity at the plasma membrane is pivotal for the maintenance of total body Na+, blood pressure and blood volume and is crucially controlled by the trafficking of ENaC to and from the plasma membrane. Recently, the COMMD (Copper Metabolism Murr1 Domain containing) family have been linked to the regulation of the trafficking (transport to and from the plasma membrane) of multiple membrane proteins, and thus the control of their abundance within the plasma membrane. All COMMD family members, including COMMD10, have been shown to be able to interact with ENaC and a number have also been shown to down-regulate ENaC, likely by increasing ENaC endocytosis from the plasma membrane suggesting a role for COMMD10 in ENaC regulation, however no studies have been performed to investigate COMMD10. Therefore, this study aimed to investigate whether COMMD10 is a novel regulator of protein trafficking and whether, specifically, COMMD10, similar to other COMMD members, is able to regulate ENaC. Through immunocytochemistry experiments, with various trafficking-associated proteins it was identified that COMMD10 co-localises with Arf1 (a small GTPase localised to the endoplasmic reticulum (ER), Golgi and endosomal compartments), but not with other ER and Golgi associated proteins, suggesting an endosomal role for COMMD10. In support of this COMMD10 co-localised with the endosomal marker transferrin-546 (Tf-546) and, when knocked-down, COMMD10 reduced protein levels of the recycling, and thus endosome, associated proteins COMMD1 and Vps35 suggesting a role for COMMD10 in trafficking between endosomal compartments and the plasma membrane. In U2OS cells with a stable COMMD10 knockdown there was an increase in endocytosis of Tf-546 as well as impaired Tf-546 recycling providing further evidence of a COMMD10 role in trafficking between endosomal compartments and the plasma membrane. A stable COMMD10 knockdown (C10 KD) of COMMD10 was developed in Fischer rat thyroid (FRT) cells using shRNA. FRT COMMD10 knockdown cells transfected with plasmids encoding αβγENaC exhibited a reduction in amiloride-sensitive short-circuit current (Isc-amil) suggesting a reduction of ENaC at the plasma membrane. Treatment of epithelia with Brefeldin-A highlighted that COMMD10 did not affect ENaC trafficking through the synthetic (i.e. ER to Golgi to plasma membrane) pathway. Results indicated that C10 KD increases the ubiquitination, and thus the endocytosis, of ENaC. In support of this FRT COMMD10 KD cells increased the endocytosis of Tf-546 from the plasma membrane providing further evidence that COMMD10 is a novel regulator of ENaC endocytosis. Preventing endocytosis in C10 KD epithelia, using Nedd4-2 siRNA or a Liddle’s mutation, however, only partially rescued Isc-amil. Studies with transferrin-546 suggested that C10 KD delays recycling of the transferrin receptor to the plasma membrane providing evidence that COMMD10 might also regulate ENaC recycling. Further support for a COMMD10 role in regulating ENaC was provided through studies with aldosterone. Aldosterone is secreted in low sodium conditions to promote sodium reabsorption through ENaC and it was identified that aldosterone regulated COMMD10, but not COMMD1, protein levels in mouse cortical collecting duct cells (M1CCD) suggesting COMMD10 regulates ENaC. Taken together, results from this study suggest that COMMD10 is a novel regulator of ENaC trafficking by regulation of Nedd4-2 mediated ENaC ubiquitination, and possibly also of ENaC recycling from endosomal compartments to the plasma membrane.

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  • Development of a Hyperspectral sensor system for model-based remote water constituent inference

    West, Matthew Thomas (2017)

    Masters thesis
    University of Otago

    This project undertook a model-based inversion of spectral data for remote sensing of water constituents, from satellite based hyperspectral sensors. As the atmosphere effects dominate the observed spectrum, a parameterised model is needed for both the atmosphere, the water/atmosphere interface and the water itself. In order to calibrate these models, a sensor was developed for recording hyperspectral data. This sensor is portable and lightweight so that is can be used to simultaneously gather downwelling irradiance, as well as upwelling irradiance from a boat or other mobile platform during a HICO satellite sensor observation. We present data from apparatus deploying this sensor and perform model based inference on this data, as well as data from the HICO system.

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  • Systematically planning and integrating intercultural communicative competence learning/teaching into the EFL curriculum/classroom to promote students’ learning motivation and confidence in ICC: A practitioner research at a tertiary institution in China

    Li, Lanping (2017)

    Doctoral thesis
    University of Waikato

    Although ICC teaching/learning in foreign language classrooms has been explored over the past few decades, few studies have experimented with systematically planning and integrating ICC teaching/learning in the EFL classroom by applying ICC theories. Very few studies on ICC teaching have included data on classroom teaching practices collected by a multi-method approach. In the context of China, where the development of ICC is emphasized in the College English syllabus, there is dearth of empirical studies on ICC teaching and no studies have trialled systematically planning and integrating ICC teaching into the EFL curriculum/classroom for non-English majors in universities to investigate how it might motivate students to learn English and how it might develop students‘ ICC and ICC confidence. This practitioner research sought to occupy the research space above. Based on an extensive review of the ICC teaching literature, this intervention study was carried out to trial applying ICC teaching and L2 learning motivation theories to the EFL curriculum/classroom, specifically an intervention class of non-English majors in a university in China through one semester. To investigate the associations of the intervention with students’ learning motivation, ICC and ICC confidence, a mixture of research methods was applied, including practitioner inquiry, action research, case study, mixed methods with explanatory design and triangulation design, and a quasi-experimental design. A multi-method approach to data collection was adopted including surveys, pre-test and post-test, students’ reflective journals, teacher‘s reflective journal and interviews. These data sets were analysed in ways appropriate to the data type, including thematic analysis and statistical analysis. The results of the qualitative and quantitative analysis were used to compare, triangulate and mutually illuminate both sets of results. The findings indicate that students’ positive attitudes toward ICC learning were related to their identification with the importance of learning/teaching ICC in English classroom and the fact that the systematic ICC learning/teaching in their English classroom had stimulated their interest and increased their learning motivation. Associations were found between systematic ICC learning/teaching and students’ improvement in learning motivation, LS, ICC and ICC confidence. A number of effective ways of systematically planning and integrating ICC learning/teaching into the EFL curriculum/classroom were found, such as a division into three learning phases, a process of six stages in ICC curriculum planning, deciding certain ICC learning/teaching objectives, and other basic dimensions and components of the curriculum, including resource selection for the ICC learning/teaching and aspects of teaching method. It is concluded that systematically planning and integrating ICC teaching into the EFL curriculum/classroom, based on the theories of ICC teaching and L2 learning motivation, has a great potential to develop students‘ ICC and ICC confidence, and promote their learning motivation as well, with a flow-on benefit to their language skills. This study is significant for its practical implications for the practice of ICC learning/teaching in the EFL curriculum/classroom; its contribution to the practical and theoretical development/support of ICC learning/teaching and L2 learning motivation theories; its applying a mixture of research methods and of data collection and analysis procedures to investigate ICC teaching. In one word, it is significant in its offering practical implications for curriculum implementation, practical implications for teacher education and language policy-making, methodological implications for research, and theoretical implications for the development of ICC teaching/learning in the EFL classroom.

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  • MRI Safe Electrodes for Spinal Cord Stimulation (SCS)

    Hartung, Dirk; Scott, Jonathan B.; McCabe, Steven Owen; Single, Peter (2017)

    Conference item
    University of Waikato

    Adding decoy filars and non-therapeutic decoy electrodes to therapeutic filars can divert and dissipate a significant fraction of captured RF energy in a distributed way along the lead. Simulated worst case local SAR values have been reduced by a factor of ten for lead lengths ranging from 200 mm to 1200 mm.

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  • Initial teacher education students’ reasons for using digital learning objects when teaching mathematics

    Hawera, Ngārewa; Sharma, Sashi; Wright, Noeline (2017)

    Conference item
    University of Waikato

    A current issue in initial teacher education (ITE) in Aotearoa, New Zealand is how students can best be supported to use digital technologies for mathematics teaching. While many ITE students are familiar with digital technologies for personal use, they are less likely to know how to incorporate them into the mathematics learning process. Supporting ITE students to become more critical, knowledgeable, skilled, and confident about using digital technologies was the main aim of the study. Forty second-year ITE students were surveyed about the Digital Learning Objects promoted by the Ministry of Education that they would choose to use to teach area measurement. Several different reasons were reported.

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  • Feasibility of storing carbon dioxide on a tectonically active margin: New Zealand

    Field, Brad D.; Lawrence, M.J.; Nicol, A.; McNamara, D.; Arnot, M.J.; Coyle, F.; Higgs, K.E.; Mountain, B.; Gerstenberger, M.; Daniel, R.; Bunch, M.A.; Barton, Barry (2015)

    Conference item
    University of Waikato

    Screening of New Zealand's sedimentary basins indicates several gigatonnes of carbon dioxide storage capacity might be available. However, carbon dioxide storage is currently untested in New Zealand and it is likely that most theoretical storage capacity will be discounted once detailed assessments are made. New Zealand's position on an active Neogene plate boundary raises additional key factors that will affect final site selection. Issues specific to New Zealand's setting include 1) rapid facies changes, syndeposition and post-depositional structural events, particularly in regions close to the plate boundary; 2) rapid subsidence and high sedimentation rates leading to overpressured reservoirs and strong water drive in some structures, which will potentially result in injectivity issues, particularly in depleted fields; 3) mineralogically immature reservoir rocks requiring assessment of injected gas-rock reactions; 4) common occurrence of faults of various scales, requiring assessments of their sealing capacity and present stress fields; and 5) distinguishing induced seismicity from common natural seismicity. Some of these risk factors will also influence the relationship between social acceptance and the design of regulations. Despite the risks, hydrocarbon producing fields in Taranaki indicate that viable reservoir-seal pairs are likely to be present. Additionally, injection of small volumes of produced water and significant natural gas storage at the depleted Ahuroa Field, have not led to noticeable induced seismicity, though large volumes expected from a carbon dioxide injection project would likely require careful site assessment for seismic risk in some areas. Natural analogue and laboratory fluid rock experiments are investigating the effects of carbon dioxide injection on reservoir mineralogy and some effects can now be anticipated. Currently produced gas from New Zealand locally contains significant carbon dioxide (up to 44% carbon dioxide in the Taranaki region and up to 30% in the Canterbury Basin) and if new discoveries also have a high carbon dioxide content they may require processing before use, with disposal of carbon dioxide. Such a large gas discovery anywhere in New Zealand could therefore stimulate rapid deployment of CCS. It is highly likely viable storage sites exist, particularly away from the current plate boundary, though the site-specific nature of site assessment is particularly important in New Zealand's geological context.

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  • Upgrading the utilization of brassica wastes: physicochemical properties and sensory evaluation of fermented brassica stalks

    Bekhit, A. E. D.; Lingming, K.; Mason, Susan L.; Zhou, J. H.; Sedcole, John R.

    Journal article
    Lincoln University

    The potential to utilize brassica harvest residue and processing waste to add-value and /or to eliminate environmental concerns through fermentation was investigated. Some physicochemical properties (moisture, protein, ash, acid detergent fibre, vitamin C, total phenolic and amino acids contents, acidity and shear and compression forces) for broccoli and cauliflower stalks before and after fermentation were measured. Considerable vitamin C and total phenolics concentrations were found in fresh broccoli and cauliflower stalks. Fermentation decreased (P < 0.001) vitamin C concentration to about 55% of that found in fresh stalks of broccoli and cauliflower and decreased (P < 0.001) total phenolics concentrations (by 15% and 28% for broccoli and cauliflower, respectively). The results from the sensory analysis indicated that the fermented broccoli and cauliflower stalks may be successful as condiment products for consumers familiar with fermented products.

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  • Corporate governance compliance and discretionary accruals: New Zealand evidence

    Bhuiyan, Md B. U.; Roudaki, Jamal; Clark, Murray B.

    Journal article
    Lincoln University

    The purpose of this paper is to investigate the effect of better compliance with corporate governance regulation on managerial accruals (discretionary accruals) in New Zealand listed companies. Unlike previous research of earnings management, Jones model (Jones 1991), Modified Jones model (Dechow, Sloan, & Sweeney, 1995) and Performance Matched Accruals Model (Kothari, Leone, & Wasley, 2005) this research focuses on free cash flow as a measure of discretionary accruals instead of cash flow from operating activities. Univariate and multivariate regression analysis was done on 70 New Zealand listed firms over the period of 2000 - 2007 (inclusive). Results found that better compliance with corporate governance reduces discretionary accruals implying lower managerial opportunistic behaviour. Consistent with existing theories and models of discretionary accruals, this research documents that free cash flow increase managerial discretion by comparing with commonly used accruals model such as Jones Model, Modified Jones Model and Performance Matched Accruals Model. This study provides insights to regulators in developing corporate governance and financial reporting guidelines. It suggests that ‘Comply or Explain’ form of soft regulation reduces managerial discretion with stock exchange listing. This research uses a comparative analysis of traditional discretionary accrual measure with free cash flow approach of discretionary accruals. Moreover, an integration approach of discretionary accrual measure was never done in New Zealand.

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  • Results from the AUSTRAL Geodetic VLBI Network

    Liu, Jia

    Masters thesis
    Auckland University of Technology

    Very Long Baseline Interferometry (VLBI) is a space geodesy technique used to determine the Celestial Reference Frame (CRF); it contributes to the definition of the Terrestrial Reference Frame (TRF) and it is the only space geodetic technique that provides the full set of Earth Orientation Parameters (EOPs), which are important for positioning and navigation on Earth and in space. Contribution of the southern hemisphere geodetic VLBI stations in the International VLBI Service for Geodesy and Astrometry (IVS) expanded significantly since the AUSTRAL VLBI program was started in 2011. The AUSTRAL geodetic VLBI network consists of five radio telescopes: WARK12M in New Zealand, three AuScope 12-m antennas (Hobart, Katherine and Yarragadee) in Australia, and HART15M in South Africa. There are theoretical models which determine coordinates and velocities of AUSTRAL stations. However, one can expect that their accuracy is not high, because they are based on limited and sparse time series of first years of AUSTRAL observations (2012–2013 for VieTrf13 and 2012–2014 for ITRF2014-IVS). Here, I include two more years of observations (up to mid-2016) to test quality of the theoretical models of the AUSTRAL stations. The latest version Vienna VLBI Software VieVS (version 2.3) is used to process and analyse geodetic VLBI observational data from the global (IVS-R1/R4) and the regional (AUSTRAL) sessions for the period from 2012 to the mid of 2016. I find that there is discrepancy between Global Navigation Satellite Systems (GNSS) and VLBI results. In some cases, there is indication that VLBI models need improvement. I compute the horizontal coordinates (NEU). I find that horizontal (North and East) components are more stable (smaller errors) than the vertical (Up) component. I find that the WARK12M VLBI Up-residual shows vertical motion about −2 cm/yr. The co-located GNSS does not show noticeable motion – much less than 1 cm/yr. The local tie survey for the same period did not show distance change between GNSS and radio telescope. I conclude that the a priori model needs adjustment. In some cases, more obervations with the Warkworth 12-m radio telescope are required. I calculate the velocities of VLBI and GNSS stations, and the baseline rates of change for both of VLBI and GNSS stations of the AUSTRAL array. I found that the ITRF2014 describes baseline rates of change is better than the VieTrf13. In some cases discrepancies between models and observations are significant. I conclude that the models of our AUSTRAL stations need to be adjusted. It is the troposphere that is one of the most important error sources for space geodetic techniques which rely on radio signals (VLBI and GNSS). To achieve accuracy of telescope coordinate determination at the millimetre level, an accurate troposphere delay modelling is needed. I investigate the tropospheric zenith wet delay (ZWD) for the AUSTRAL stations. I discuss the seasonal variations (signals) of the ZWD. I compare the ZWD results obtained from VLBI with the ZWD results based on the GNSS measurements for the Warkworth Global Geodetic Observing System (GGOS) station. I find that the geodetic results for VLBI and GNSS present a good agreement. I conclude that the AUSTRAL sessions are suitable to measure ZWD. I consider VLBI sessions which involve AUSTRAL stations only and sessions that include AUSTRAL station and other IVS stations. I compute and compare the EOPs and demonstrate that the more stations are involved and the more regular is the distribution of IVS stations on the globe, the higher the accuracy of EOPs determined in these sessions.

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  • The impacts of institutional differences in relation to intellectual property rights protection on foreign market direct investment: FDI inflows and modes of foreign market entry

    Mo, Xiaoxin (2017)

    Masters thesis
    Victoria University of Wellington

    This Master‘s thesis seeks to consider the impacts of institutional distance regarding IPR protection on Foreign direct investment’s (FDI) internationalization strategies. Estimated at approximately US$ 1.8 trillion in 2015 and sitting at its highest level since the global economic and financial crisis in 2008 (UNCTAD, 2016), FDI flows are fast becoming a focal issue of global business. Developing Asia, for example, has emerged as the world’s largest FDI recipient region in the world, which has attracted a wide and public attention. China, in particular, is the largest recipient of FDI among the emerging economies. In 2014, it overtook the US as the most popular destination for multinational enterprises (MNEs). To date, most academic interest has focused on how the institutional environment of the host country affects both the overall volumes of FDI (e.g., Lee & Mansfield, 1996; Smarzynska Javorcik, 2004), and the modes of entry strategy (e.g., McCalman, 2004; Dikova & Witteloostuijn, 2007). However, other areas of research also consider institutional distance, and the magnitudes and asymmetric effects of institutional distance (e.g., Cuervo-Cazurra & Genc, 2011; Phillips, Tracey, & Karra, 2009; Zaheer et al., 2012). In this context, this thesis, uses China as a sample of FDI recipient to seek to understand how the directions of institutional distance affect FDI’s flows and MNEs’ choice of entry mode into the host country. In particular, the research questions being addressed in this study are: (1) How does the bidirectional distance between home and host country regarding IPR protection affect FDI’s inflows to China? and (2) How does this bidirectional distance regarding IPR protection influence MNEs’ choice of entry mode? Using a quantitative research design, two dependent variables are examined in this study: FDI inflows and entry mode (wholly-owned subsidiaries (WOS) versus joint ventures (JVs)). Using the institutional theory as its theoretical underpinning, this study hypothesizes that IPR distance between home and host countries negatively affects FDI inflows to the host market. It also hypothesizes that IPR distance is positively related to MNEs’ choice of WOS as an entry mode as opposed to JVs. Both hypotheses build on the new notion regarding the directions of institutional distance that MNEs’ strategies and behaviours are divided into positive and negative directions. This consideration of directions of institutional distance differs to that of the general institutional approach, which typically clusters all regulative, normative and cognitive pillars within the institutional distance. However, this research focuses on the single regulative distance of IPR protection. Using the 691 collected observations of FDI flows to China from 2006 to 2012, hypothesis 1 was tested by employing the estimation techniques of panel linear regression. To further assess hypothesis 2, 801 instances of foreign market entry of FDI in China between 2008 and 2012 were analysed by logistic regression. From the panel linear regression model, the empirical results show that the larger the distance of IPR protection between home and host countries, the fewer the flows of FDI that entered into China. Such results are consistent with previous mainstream literature suggesting that greater institutional distance significantly diminishes the MNEs’ intentions to invest (e.g., Du, 2009; Berry et al., 2010). Moreover, logistic regression for hypothesis 2 reveals that IPR distance appears to be significantly and positively associated with the choice of WOS. This means that the tendency of MNEs from countries with a higher distance of IPR protection to enter China’s market by means of WOS (as opposed to JVs) will decrease. This result is in line with previous studies that note that larger institutional distance is associated with a lower level of equity ownership mode, such as JVs over WOS (e.g., Xu et al., 2004; Xu & Shenkar, 2002; Estrin et al., 2009). The greatest takeaway from this study is that it advances knowledge about the impact of the directions of IPR distance and provides new opinions on the debate around the asymmetric effect of institutional distance on internationalization decisions. This study also offers practical implications for both firm managers and public policy makers.

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  • Sensing the City - Mapping the Beat. A rhythmanalysis of music-making in Wellington and Copenhagen

    Rochow, Katie (2017)

    Doctoral thesis
    Victoria University of Wellington

    The idea of rhythm has figured as a key conceptual and empirical motif in current research on (urban) space, place and everyday life. Urban spaces are considered polyrhythmic fields, a compound of varied everyday life and spatial rhythms, which produce a particular, but ever-changing, complex mix of heterogeneous social interactions, mobilities, imaginaries and materialities (Edensor 2010). Music-making in the city therefore constitutes and is constituted by a plurality of urban rhythms including the movement between different locations as well as regular temporal patterns of events, activities, experiences and practices as well as energies, objects, flora and fauna which shape the music-maker’s mundane ‘pathways’ through the city. Based on current ethnographic fieldwork in the urban spaces of Wellington (Aotearoa/New Zealand), and Copenhagen (Denmark) this project proposes a way of capturing, understanding and interpreting the multi-faceted rhythmical layout of urban spaces. It will do so by introducing a rhythmanalytical methodology, which draws on interviews, participant generated photographs and mental maps as analytical tools for capturing the interwovenness of socialities, atmospheres, object, texts and images in people’s everyday lives and in this way affords opportunities for attending to the multiple rhythms underlying music-making in the city. The use of cartographic and photographic means of representing these rhythmical dimensions allows us to better attend to an affective register that is often overlooked in studies of music-making. It makes visible some of the ways in which places, from the home to the studio to the performance venue and points in-between form a connective tissue, which anchors the music-makers to the city as well as lends the city its ambience, and, more importantly, its affective charge. As such, the manner in which mood, feeling, a “sense of place,” is evoked through the visual representation of music-makers’ everyday life suggests how the scenic aspects of the city work to simultaneously frame, mediate and facilitate meaningful experiences of place. Consequently, this study documents, through a unique medley of research methods, the way in which music-making serves as a vehicle for the social production of place and the creation of an affective attachment to that place both individual and collective.

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  • Design and Synthesis of Antiviral Iminoribitol C-Nucleosides

    Li, Ye (2017)

    Masters thesis
    Victoria University of Wellington

    Infections caused by RNA viruses, such as Ebola and Zika, continue to exist worldwide as significant public health problems. In response to the urgent need for safer and more efficacious treatment options to treat infections caused by RNA viruses, the pharmaceutical and biotechnology industries have devoted significant efforts over the last two decades to discovering and developing new antiviral agents. One such antiviral, Sofosbuvir®, was approved by the US Federal Drug Administration (FDA) in 2014 and has revolutionized the treatment of Hepatitis-C. Sofosbuvir® was the second largest selling drug in the world in 2016 and in just twenty-one months Gilead reported sales worth $26.6 billion USD. The strategy of using nucleoside analogues to inhibit viral RNA dependent RNA polymerase (RdRp) has been pursued since the 1970s, and exemplified by the discovery and development of ribavirin. The natural substrates of RNA polymerases are nucleoside triphosphates and often the efficacy of nucleoside analogues as antivirals are dependent on their ability to be converted by the host or virus to mono-, di-, and ultimately tri-phosphate analogues which block the active site of RNA polymerase as an analogue of the substrate causing chain termination. Recently Biocryst Pharmaceuticals (Biocryst) described the anti-viral properties of Immucillin-A (Galidesivir), an iminoribitol based nucleoside analogue, which was found to have broad spectrum antiviral activity especially against RNA viruses including Ebola. Researchers at the Ferrier Research Institute (Ferrier) have synthesized an analogue of Immucillin-A, 8-aza-Immucillin-A (AIA) which shows comparable activity to Immucillin-A, in anti-viral screens against Ebola, and this antiviral activity forms part of a US patent application. The Ferrier is keen to further exemplify this compound class through the synthesis of analogues of both Immucillin-A and AIA as well as improve the overall synthesis of the lead compound AIA. Included as part of this study is the synthesis of pro-drugs of these iminoribitol based nucleoside analogues. Prodrugs are metabolized inside the body and are often converted to the corresponding pharmacologically active form. In general, prodrug strategies have improved the bioavailability and efficacy of many drugs. In particular, prodrugs strategies involving nucleoside analogue antivirals, which target RNA polymerase, have been particularly effective as they ensure conversion to the monophosphate in vivo. Conversion to the 5’-monophosphate form of a nucleoside analogue is the rate limiting step to the inhibition of the RNA polymerase – prior to its conversion to the triphosphate analogue. The prodrug is effectively a protected monophosphate, and is then readily converted to monophosphate by the host and then onto the di- and tri-phosphate by kinases in both the host and virus. ProTide prodrugs, such as Sofosbuvir® provide a verified strategy for improving anti-viral activity and hence our desire to synthesize pro-drugs of all our iminoribitol based nucleoside analogues. This research thesis also involved repeating the known synthesis of the Immucillins, in particular, Immucillin-H (Forodesine), which requires in excess of 20 linear synthetic steps to make. The linear synthetic route to Immucillin-H was used instead of the more convenient convergent method developed by the Ferrier as several key synthetic intermediates in this progress were utilized in the attempted synthesis of some of the planned nucleoside analogues of AIA. As part of this work the candidate learned aspects of scaling up chemical reactions and the critical analysis of both reaction hazards and reagent compatibilities at scale. Where possible and given the number of synthetic steps involved the candidate was also interested in improving the yields of the building blocks involved in the synthesis of the Immucillins with limited success.

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  • Transport properties in nanostructured thermoelectric materials and single crystal perovskites

    Ng, Michael (2017)

    Masters thesis
    Victoria University of Wellington

    Energy consumption worldwide is constantly increasing, bringing with it the demand for low cost, environmentally friendly and efficient energy technologies. One of these promising technologies is thermoelectrics in which electric power is harvested from waste heat energy. The efficiency of a thermoelectric device is determined by the dimensionless figure of merit ZT = σS²T/k where σ is the electrical conductivity, S is the thermopower, k is the thermal conductivity, and T is the average temperature. In this thesis we investigate the use of nanostructuring, which has been known to lead to significant reduction in the lattice thermal conductivity to maximise the figure of merit. One of the most successful bulk thermoelectric materials is Bi₂Te₃, with a ZT of unity at room temperature. Here we investigate the effects of nanostructuring on the thermoelectric properties of Bi₂Te₃. Sub-100 nm ₂Te₃ nanoparticles were successfully synthesized and the figure of merit was found to be ZT ~ 5X10⁻⁵ at room temperature. The effect of a ligand exchange treatment to replace the long chain organic ligand on the as-synthesized nanoparticles with a short chain alkyl ligand was explored. After ligand exchange treatment with hydrazine the figure of merit of sub-100 nm Bi₂Te₃ was found to increase by two fold to ZT ~ 1X10⁻⁴ at room temperature. Overall the figure of merit is low compared to other nanostructured Bi₂Te₃, this was attributed to the extremely low electrical conductivity. The thermopower and thermal conductivity were found to be ~96 μVK⁻¹ and ~0.38 Wm⁻¹ K⁻¹ at 300 K respectively, which show improvements over other nanostructured Bi₂Te₃. Further optimisation of the figure of merit was also investigated by incorporating Cu, Ni and Co dopants. The most successful of these attempts was Co in which 14.5% Co relative to Bi was successfully incorporated into sub-100 nm Bi₂Te₃. The figure of merit of nanostructured Bi₁.₇₁Co₀.₂₉Te₁.₇₁ alloy was found to increase by 40% to a ZT ~ 1.4X10⁻⁴ at room temperature. Although overall the figure of merit is low, the effect of Co alloying and hydrazine treatment shows potential as a route to optimise the figure of merit. A potential novel material for thermoelectrics applications is inorganicorganic perovskite single crystals. Here we report a synthetic strategy to successfully grow large millimetre scale single crystals of MAPbBr₃₋xClx, FAPbBr₃₋xClx, and MAPb₁-xSnxBr₃ (MA = methylammonium and FA = formamidinium) using inverse temperature crystallisation (ITC) in a matter of days. This is the first reported case of mixed Br/Cl single crystals with a FA cation and mixed Pb/Sn based perovskites grown using ITC. The bandgap of these single crystals was successfully tuned by altering the halide and metal site composition. It was found that single crystals of FAPbBr₃₋xClx were prone to surface degradation with increased synthesis time. This surface degradation was observed to be reversible by placing the single crystals in an antisolvent such as chloroform. A tentative model was proposed to analyse the IV characteristics of the single crystal perovskites in order to extract mobilities and diffusion lengths. The MAPbBr₃ and MAPbBr₂.₅Cl₀.₅ single crystal mobilities were found to be between 30-390 cm² V⁻¹ s⁻¹ and 10-100 cm² V⁻¹ s⁻¹ respectively, the diffusion lengths were found to be between 2-8 μm and 1-4 μm respectively. This is an improvement over polycrystalline thin film perovskites and comparable to other single crystal perovskites. The conductance of MAPb₁-xSnxBr₃ based perovskites was found to increase by 2 orders of magnitude even with just 1% of Sn incorporated. The thermal conductivity of MAPbBr₃ single crystals was found to be ~1.12 Wm⁻¹ K⁻¹ at room temperature which is reasonable low for single crystals, however no other thermoelectric properties could be measured due to the self cleaving nature of the single crystals with decreasing temperature and the high resistivity of the material.

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  • Seagrass: A Dynamic System

    Duncan, Alison (2017)

    Masters thesis
    Victoria University of Wellington

    Small herbivorous invertebrates consume algal epiphytes, reducing negative effects (e.g. shading) on seagrass. Much research to date has focused on crustacean grazers, and comparatively little on gastropods. The aim of this research was to 1) examine seasonal and spatial variation in seagrass and associated gastropods in a large, tidal estuary and 2) examine the response of seagrass and epiphytic algae to nutrient enrichment and grazing pressure in a laboratory experiment. Surveys were conducted in summer and winter of 2016 to assess the seasonal fluctuations in the associated gastropods and relationships with seagrass and epiphyte biomass within three sites in the Porirua Harbour. Seagrass, gastropods and epiphytic algae showed seasonal trends, including evidence of a loss of grazer control on epiphytes during winter. Potamopyrgus estuarinus, Notoacmea scapha, Diloma spp. and Micrelenchus spp. were the dominant gastropod grazers in the system in both seasons. The gastropod assemblage and seagrass characteristics differed between sites, likely in response to small scale differences in abiotic factors. Seagrass from Elsdon (a site with elevated nutrient levels) and Browns Bay (a relatively pristine site) were used to investigate the role of select grazers and nutrient enrichment on epiphyte and seagrass growth. Nutrient treatments represented nitrate and phosphate concentrations of Elsdon (High), a 20% increase (High+) and a control (no addition). Little evidence was found for epiphyte regulation by gastropods, nor did epiphyte loads increase with nutrient addition. Seagrass from Browns Bay responded more strongly to High+ treatments than that of Elsdon. The results suggest that seagrass from Elsdon is adapted to the site’s high nutrient loads, where seagrass from Browns Bay is not. The results of this thesis support prior research findings of high variation in seagrass over a small scale, and adds to the currently lacking information on the role of micro-grazers in New Zealand’s seagrass meadows.

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  • Museum Diplomacy: Developing cultural partnerships between New Zealand and China

    Bayly-McCredie, Lillian (2016)

    Masters thesis
    Victoria University of Wellington

    Museums play an increasingly important role in cultural diplomacy. New Zealand cultural organisations support international objectives by assisting cultural exchange, increasing mutual understanding and connecting key players. However, the intersection between museum and government activity is often regarded with scepticism, stemming from a general antipathy towards instrumentalism in museum and cultural policy studies literature. This research draws on recent work by Nisbett (2013), which revealed how British cultural organisations inverted instrumentalism—the use of cultural ventures by governments to help achieve goals in other areas—to achieve their own goals. The literature suggests that British museums strategically promoted their cultural diplomacy activity to formulate cultural policy and expand the scale of their international activity. This provides a useful model for the New Zealand cultural sector to build on, in its unique environment. This dissertation addresses this gap in the literature by investigating the intersection of museum and government activity between New Zealand and China. Through a case study of the partnership between Te Papa and the National Museum of China the research explored the state of cultural organisation partnerships, and assessed to what extent museums benefit by acting instrumentally. Interviews were conducted with ten cultural sector professionals and grounded theory was used to analyse the data. This research found that New Zealand’s national museum positioned itself as willing and able to engage in cultural diplomacy activity, in order to develop its international activity, and offer benefits in return to its principal funder, the government. Results suggested that while the museum has not utilised instrumentalism to impact cultural policy in New Zealand, there is scope to develop this. Consequently, the research identifies an emerging area in museum practice, ‘museum diplomacy’, which I define as the developing practice of intersecting activity between international museum work and state-sponsored cultural diplomacy. The research contributes to museum and cultural policy studies literature by producing modest, yet original data about museum partnerships and cultural diplomacy in New Zealand, and provides insights for government and the cultural sector in international cultural partnerships. It echoes the critical view of the disjuncture between museum theory, policy and practice, and concludes by discussing some recommendations and calling for further research to be conducted on museum diplomacy.

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  • Towards a curatorial continuum or How to fire a gun and time-travel

    Phillips, Bruce E. (2017)

    Masters thesis
    Victoria University of Wellington

    This thesis questions the ethics of curatorial agency: an issue that has plagued the profession since the influence of institutional critique of the 1960s. The proliferation of the ‘curatorial turn’ during the 1990s developed out of this legacy of institutional critique by grouping a diverse range of alternative practices that aimed to question curatorial agency. Curator Maria Lind defines this shift by making a methodological distinction between ‘curating’ and the ‘curatorial’. This is a binary division that posits curating as conventional practice that maintains hegemonic power structures and the curatorial as progressive and emancipatory. However, critics and curators such as Paul O‘Neill and Nina Möntmann argue that methodologies of the curatorial turn have become compromised by personal, institutional, political and economic motivations. Due to this, it is apparent that a shift in methodology alone is not sufficient to question the ethics of curatorial agency and that Lind's dichotomy of curating and the curatorial requires revision. This study therefore explores how curators practice by studying different methodologies and to understand why curators practice by considering to what extent motivations influence the application of a curator’s methodology. The research specifically addresses these questions in relation to contemporary art curating within the broader framework of museum and heritage studies. To do so, I have put my own curatorial practice under scrutiny, using a range of mixed qualitative methods such as autoethnography, in order to delve deep into the decision-making process. My research consists of six exhibition case studies that pertain to one of three common exhibition forms: group, solo or process-led exhibitions. Through a cross case analysis of these different exhibitions my findings suggest that there is not a distinct division between curating and the curatorial. Instead, I reveal that there is a complex interplay between spectrums of methodology and motivation. From this perspective, I argue for a new philosophy of curating that considers curatorial practice as an emergent spectrum charged with infinite possibilities, what I call the curatorial continuum.

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  • Modelling the distribution of an oviparous skink, Oligosoma suteri

    Stenhouse, Vaughn I. (2017)

    Masters thesis
    Victoria University of Wellington

    Predicting species distributions relies on understanding the fundamental constraints of climate conditions on organism’s physiological traits. Species distribution models (SDMs) provide predictions on species range limits and habitat suitability using spatial environmental data. Species distribution modelling is useful to estimate environmental conditions in time and space and how they may change in future climates. Predicting the distribution of terrestrial biodiversity requires an understanding of the mechanistic links between an organism’s traits and the environment. Implementation of mechanistic species distribution models requires knowledge of how environmental change influences physiological performance. Mechanistic modelling is considered more robust than correlative SDMs when extrapolating to novel environments predicted with climate change. I examined the spatial distribution and the impact of climate change on incubation duration of an endemic, nocturnal skink, Oligosoma suteri. My research focused on the ways a microclimate model with local weather data and degree-days can predict O. suteri’s distribution and affect incubation duration. Using a microclimate model (NicheMapR), I generated hourly soil temperatures for three depths in two substrate types (rock and sand) at a 15 km spatial resolution for the entire coastline of New Zealand and for seven depths for one substrate type (rock) for the coastline of Rangitoto/Motutapu Island at a 20 m spatial resolution. I estimated the minimum number of degree days required for successful embryonic development using a minimum temperature threshold for O. suteri eggs. I apply the incubation duration predicted by the model to map potential distribution for the two different spatial resolutions (15 km and 20 m) and I also include a climate change component to predict the potential effects on incubation duration and oviposition timing. My results from the New Zealand wide model indicate that embryonic development for O. suteri may be possible beyond their current distribution, and climate warming decreases incubation duration and lengthens the oviposition period for the New Zealand wide map. I generated maps of predicted incubation duration with depth for a coastal habitat at a higher resolution for Rangitoto/Motutapu Island. Incubation duration varied by depth with higher number of days to hatch predicted for greater depths. Temperature data loggers were installed at two different sites at three depths and were compared to the Rangitoto/Motutapu Island microclimate model. Modelled incubation durations were consistently shorter than data logger incubation durations across all three depths at both data logger sites. Species distribution model with coarse spatial and climate data can predict where soil temperatures would be suitable for successful development. A higher spatial resolution can reveal variation in incubation duration within sites indicated as suitable from the coarse resolution map. By using two different spatial extents initial starting points can be identified for which a higher resolution model can be applied to better inform management decisions relating to conservation actions and the effects of climate change for O. suteri and other species.

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  • Cultivating Climate Consciousness: Agritourism Providers’ Perspectives of Farms, Food and Place

    Cavaliere, Christina T. (2017)

    Doctoral thesis
    University of Otago

    The aim of this PhD research is to explore climate change perspectives of agritourism providers in New Jersey (NJ) located in the United States (US). Research objectives include the assessment of agritourism providers’ narratives around the status of farms, food and the constructions of place as related to climate change. The forces driving climate change are a complex mix of biophysical, cultural and socio-economic factors. This human induced climate challenge is caused by increases in emissions from fossil fuels resulting from economic and population growth. Farms and food production both contribute to and at the same time are impacted by climate change. As opposed to industrial agriculture, the examination of local agriculture as a source of sustenance, resilience and reconnection to place is significant as human population increases. Agritourism is considered as any business conducted by a farmer for the enjoyment or education of the public, to promote the products of the farm and to generate additional income. The intrinsic, transformative and socio-cultural components of agritourism hold value that is yet to be fully understood by increasingly urbanized, globalised and time-space-compressed societies. This examination of agritourism providers’ narratives concerning climate change is particularly relevant to NJ as it is the most densely populated geo-political boundary in the US. Using a qualitative inquiry approach, this research utilizes social constructionism and is understood as a collective generation and transmission of meaning. The empirical material was collected via a series of 36 semi-structured, open-ended interviews that lasted an average of two hours each and were conducted over a five-month period. Interwoven participant and researcher reflectivity regarding place consciousness and connection to landscapes through food was critical to the co-constructed narratives. In addition, the research method of co-constructed photography was employed in order to more deeply facilitate embodied narratives. Furthermore, publicly documented material was collected from 52 newspaper articles and 11 documentaries related to the research themes and were utilised for additional and comparative information. Content analysis of the empirical data resulted in the identification of six primary themes that include: consumption, production, time, alternate ways of knowing, nature-based experiences and knowledge networks. There are two main theoretical elements underpinning this research. These elements are directly related to the economic and population drivers of the climate challenge and were utilised to explore the human relationship to these issues. First, the economic concept of degrowth as related to climate change is presented along with the New Economics Framework (NEF). The second theoretical component is related to agritourism and place consciousness. Farms and resulting foodscapes can serve to develop connections and holistic understandings that embed individuals within the social and natural world. A Multidisciplinary Framework for Place Conscious Education (MFPCE) was applied to deconstruct themes derived from the empirical data relating to place consciousness. The research findings indicated that there is an increasing concern related to climate change implications for agritourism providers. At the same time, there is strong evidence that the participants are not equipped with information to begin employing mitigation or adaptation strategies. Agritourism providers involved with organic practices were more concerned and informed about climate change than those involved in conventional agriculture. The status of farms was identified as a biocultural conservation issue due to population pressure and land-use challenges resulting in the impending total build-out of the state. The presence of specific social movements that address the climate challenge were identified as part of sustainability focused agritourism sites. Participants also discussed related activities that included Community Supported Agricultural (CSA) schemes, relocalisation of food consumption through a food-labelling programme, farming apprenticeships and the development of localised speciality foods including aquaculture. Participants understood these social movements and related activities as approaches to engaging with new economics for transitions to post-carbon livelihoods. The multi-theoretical roles of temporality and temporal relationships were identified and contributed as new indicators to the NEF and the MFPCE frameworks. In summary, participant narratives involving farms, food and place were explored as a way to further understand more nuanced meanings of the human relationship to climate change. This research furthers qualitative agritourism research from an interpretivist perspective and within a region that is understudied. Through the amalgamation of literature, empirical findings and the contribution of new framework indicators, this research explores aspects of cultivating new economic and place-based climate consciousness within the agritourism context.

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  • Integration of Science, Mathematics and Technology

    Mathew Thomas, Tiju (2017)

    Doctoral thesis
    University of Waikato

    This research focused on studying the integration of science, mathematics and technology in a technological design context. The daily classroom practices of a teacher and 19 of his students (aged 15-16) in a technology class were analysed with a focus on the knowledge and skills used while designing individualised projects (street luge gravity-powered vehicle) with a view to identifying the integration of cross-disciplinary knowledge. This research is aligned with the elements of both interpretive and critical theory paradigms. The focus of the interpretive paradigm rests on how students construct meaning from their personal experiences and their world view. Critical theory is used to create a platform for integration by understanding the current practices and phenomena in a technology classroom to develop strategies that could be implemented in other classrooms to create an integrative learning environment.

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  • Ideologies of Nature and Sustainability: A critical discourse analysis

    Tulloch, Lynley (2017)

    Doctoral thesis
    University of Waikato

    In exploring ideologies of nature, sustainability and EE, I have had several goals in mind. Firstly, I want to trace the continuities and disruptions in Western ideologies of nature, and in particular, to locate them within the material context of the historical trajectory of the capitalist mode of production (CMP). That is, the ideologies of nature explored in this thesis are treated as integral to the historical and dialectical unfolding of the CMP. Many historical ideas on nature, particularly those since the Enlightenment, have become incorporated in dominant forms of social thought that are integral to Western capitalist development. In the present era of neoliberal-led global capitalism, these same fundamental ideologies are expressed in neoliberal forms within policy contexts, which are explored in the latter part of this thesis. Initially, I explore these ideologies of nature using Foucault’s genealogical strategy. This exploration is detailed in the first two articles in this thesis. These articles provide a foundational platform to analyse how the neoliberal project has harnessed dominant, common-sense ideologies of nature (for example, nature as benevolent and all-giving; nature as an ecosystem) and articulated them with capitalist ideologies (nature as resource, commodity or service for humankind). Through this discursive struggle for neoliberal ascendency, basic capitalist ideologies of nature have been reasserted and brought to the foreground. In this respect, I hope to capture the essential and invariant ideological core of the capitalist view of nature; how its form changes over time and space and, in particular, to examine its mid-range expression in this neoliberal era. Secondly, this thesis aims to document and analyse these ideologies of nature in terms of their humanist, androcentric and anthropocentric orientation. It is argued that these are also integral to the core and essential form of the capitalist view of nature. This is significant to my critique, in the latter half of this thesis, of EE, EfS) or EfSD policy. As Michael Bonnett (2007) has argued, official environmental education policy globally largely ignores the question of nature. In short, it has become invisible as dominant capitalist ideologies of nature seek to redefine it in instrumental terms as ‘resource’ or ‘ecosystem service’. Accordingly, I demonstrate that ideologies are not clearly demarcated and contained within labelled categories but are rather divergent and interlaced with a range of presuppositions. It is in uncovering underpinning premises about our relation as humans to nature within discursive positionings that is central to the analysis of environmental education. The meaning of ‘nature’, our underlying attitude and our relationship to it is thus of critical significance to this thesis. Thirdly, this thesis explores how these ideologies manifest within the political struggles of our times. I intend to demonstrate in this thesis, that neoliberal ideologies of nature operating within specific policy settings are constitutive of a particular form of the capitalist worldview concerning human-nature relations.

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