1,400 results for Thesis, 2017

  • Effects of herbicides on both adaptive and acquired antibiotic resistance

    Hill, Amy M. (2017)

    Masters thesis
    University of Canterbury Library

    Antibiotic resistance is an increasingly serious global health issue that will not be solved without serious and considered intervention. In order to effectively combat increasingly resistant bacteria, a better understanding of the factors influencing the development of antibiotic resistance is necessary. Previous work from this lab has shown that commercial herbicide formulations can induce adaptive antibiotic resistance in Escherichia coli and Salmonella enterica serovar Typhimurium (Kurenbach et al., 2015). To investigate the breadth of this response, Staphylococcus aureus was exposed to the same set of commercial herbicide formulations and antibiotics and three additional antibiotics commonly used to treat S. aureus infections. The pattern of herbicide-induced changes in antibiotic tolerance was similar but not identical to those observed for E. coli and S. enterica. The magnitude of changes in minimum inhibitory concentration (MIC) was often smaller for antibiotics that were used in both sets of experiments, while the largest changes were observed for the new antibiotics. These effects were observed at herbicide concentrations below application rates and, in some cases, at concentrations within the maximum residue limits (MRLs) allowable in animal feed and human food as defined by the Codex Alimentarius Commission (Codex Alimentarius Commision, 2016). Whether the adaptive responses to the herbicides can lead to shifts in the population frequency of acquired antibiotic resistance was also tested. Specific combinations of herbicide and antibiotic that caused either increases or decreases in antibiotic tolerance were investigated in more detail. In two combinations of herbicide and antibiotic, ciprofloxacin + Kamba and ciprofloxacin + Roundup, that caused adaptive resistance to the antibiotic an increased frequency of acquired resistance was observed in S. enterica. When two strains of E. coli with differing antibiotic resistance were exposed to a combination of herbicide and antibiotic, tetracycline + Roundup or streptomycin + Kamba, that caused a decrease in antibiotic tolerance, increased selection in favour of the resistant bacteria was observed.

    View record details
  • Comparing syntactic persistence in written and spoken monologue

    Middendorf, Jennifer (2017)

    Masters thesis
    University of Canterbury Library

    Syntactic persistence, the tendency for speakers to repeat recently-used syntactic structures, has been well demonstrated in dialogue and in single-sentence monologue primed by reading aloud pre-prepared material. Models advanced to explain syntactic persistence assume that priming will also occur in extended monologue, but there is no clear evidence that this is so. This thesis examines within-speaker syntactic persistence of the genitive alternation in spoken and written monologue from the QuakeBox corpus and the Press database, two New Zealand corpora selected for their close match of time period, geographic location, and topic. Two research questions are considered: is priming present in extended monologue, and does priming differ between speech and writing? In order to address these questions, I use binomial mixed-effect models to find the relative contribution of factors predicted to affect genitive choice and priming, and compare the relative impact of these factors, and the overall effect of priming, on the two corpora. The findings of my research indicate that syntactic priming is present in extended monologue, and that this priming occurs more frequently in speech than in writing. My results also support observations in the existing literature that genitive choice is affected by animacy, the presence of a sibilant sound, and the semantic relationship between possessor and possessum. While this study was not able to offer conclusive insights into the differences between α- and β-priming, and the issue of priming in nested structures, my findings indicate that these would be promising areas for further research.

    View record details
  • Characterising landscape and sea level dynamics to predict shoreline responses over the next 100+ years in a high energy tectonic setting, Kaikoura, New Zealand

    Berger, Hannah Victoria (2017)

    Masters thesis
    University of Canterbury Library

    This thesis examines local scale landscape dynamics and coastal responses to climate change along the tectonically active, high energy Kaikoura coastline, South Island, New Zealand. In New Zealand, the majority of urban infrastructure is built along low-lying coastal plains. As a result, expanding coastal communities face increasing exposure to coastal hazards, which will potentially be exacerbated by climate change-induced adjustments in sediment supply, wave climates and sea levels, amongst other factors. Sea level around New Zealand has been predicted to rise between 0.8 m and 1.0 m by 2115 as a response to increasing global temperatures. In Kaikoura, local relative sea levels may vary from regional projections based on local sediment dynamics in response to; local tectonic uplift and co-seismic sediment delivery, increased rainfall and storm intensity, ocean climate and tides. Local sediment dynamics are important to consider when managing relative sea-level variations, in terms of assessing erosion response affected by sediment supply. New Zealand Coastal Policy Statement (NZCPS, 2010) Policy 24 states that the effects of climate change on coastal sediment dynamics should be factored into 100 year hazard risk assessments. To this date there has been no combined assessment on tectonic, climatic, and anthropogenic controls on local sediment dynamics, to predict mixed sand and gravel morphology response to future climate change and sea level variation along the Kaikoura coastline. The main objective of the research is to predict how coastal geomorphology in Kaikoura is likely to respond to local tectonic and climate change- induced adjustments in landscape and sea level dynamics over the next 100+ years. In order to fulfil the research objective, the primary focus of this research was developing a conceptual framework for the preliminary assessment of local sediment dynamics as part of a sea-level rise response matrix. The methodology was developed using a Kaikoura area case study, including the coast between the Hapuku and Kahutara Rivers, Kaikoura Peninsula and the adjacent coastal progradation plain, and Seaward Kaikoura Ranges. This area encompasses key coastal sediment processes and controls in a small well-constrained region that produced findings that can be scalable to other areas in New Zealand and elsewhere. Tectonics, climate, and human interventions were identified as the main controls on local sediment dynamics in Kaikoura. Key physical (faults, watersheds, landforms) and anthropogenic (hard/soft engineering structures, regulatory frameworks) factors influencing the sediment dynamics were assessed at different temporal and spatial scales. Various climate, river gauge, and beach survey data alongside local tectonic assessments were used to characterise and assess each control. Determining how each control influences local scale sediment dynamics proved challenging in a relatively sparse data context. Rainfall, ocean climate, and beach profile data analyses provided sufficient information to construct a conceptual model for the preliminary assessment of local sediment dynamics, how tectonic and climate change-induced adjustments could affect sediment supply and how future relative sea level may manifest in the Kaikoura region.

    View record details
  • Narrating connections and boundaries : constructing relatedness in lesbian known donor familial configurations.

    Surtees, Nicola Jane (2017)

    Doctoral thesis
    University of Canterbury Library

    In a time of unprecedented possibilities for intimate life, lesbian known donor reproduction is an emerging form of kinship practice. While experienced as unique to the biographies of particular lesbian couples, known donors and their partners, practices of relatedness occur against the background of neoliberal discourses, processes of normalisation and legislative frameworks that are increasingly responsive to the rights claims of lesbian parents. This thesis investigates this phenomenon in contemporary New Zealand. Examining the meanings attached to cultural constructs such as ‘kinship’, ‘family’, ‘parenthood’, ‘motherhood’ and ‘fatherhood’, the thesis illustrates how familial boundaries and sets of relations are narratively constructed. The research draws on interviews with 60 women and men across 21 lesbian known donor familial configurations at different stages of forming family through known donor insemination, focusing in depth on nine core family narratives. Participants included lesbian parents and parents to be, gay and heterosexual known donors, and partners of donors. The thesis argues that participants are innovative in conformity and through constraint. Although the participants live amid the same dominant heteronormative public narratives, they are differently normative. They pursue different familial scenarios, which creates different possibilities for lesbian couple and parenting selves and identities relative to donors and their partners. The picture emerging suggests donors and partners remain supplementary to lesbian couples. How their status is expressed is a central theme of the thesis that demonstrates the power of neoliberal agendas of personal responsibility, freedom, agency and choice. Tensions between a sense of empowerment and constraint in family-building activities are closely linked to these agendas. Contributing to debates about the operation of homonormativity in a neoliberal context, this thesis explores the discursive power of heteronormative family models and the implications of this for innovation in the intimate lives of same-sex and heterosexual subjects.

    View record details
  • Numerical modelling of groundwater - surface water interactions with the Double-Averaged Navier-Stokes Equations.

    Dark, A. L. (2017)

    Doctoral thesis
    University of Canterbury Library

    The ability to model groundwater and surface water flows as two interacting components of a single resource is highly important for robust catchment management. Existing methods for spatially-distributed numerical modelling of flow in connected river-aquifer systems treat rivers and aquifers as separate sub-domains, with different governing equations for the flow in each. Mass-fluxes exchanged between the sub-domains are modelled using one of several coupling methods, which do not accurately represent the physics of the flow across the interface between the surface and subsurface flows. This can be problematic for model stability and mass conservation. This thesis investigates the feasibility of modelling interacting surface water and groundwater flows in a single domain, using a single system of equations. It is shown that the governing equations in existing numerical models for river and aquifer flow can be derived from the Navier-Stokes Equations. A time- and space-averaged form of Navier-Stokes Equations, the Double-Averaged Navier-Stokes (DANS) Equations, can be used to model both groundwater and surface water flows. The volume- averaging process allows the porous medium to be represented as a continuum. A novel two-dimensional numerical model is developed from the DANS Equations to simulate flows in connected groundwater and surface water systems. The DANS equations are solved using the finite-volume method. The model simulates two-dimensional flow in a vertical slice. This allows the horizontal and vertical velocity components and pressure to be modelled over the depth of a stream and the underlying aquifer or hyporheic zone. The model does not require the location of the interface between surface and subsurface flows to be specified explicitly: this is determined by the spatial distribution of hydraulic properties (permeability and porosity). The numerical model handles the transition between laminar and turbulent flows using an adaptive damping approach to modify the terms in a single-equation turbulence model, based on a locally-defined porous Reynolds number, Rep. This approach removes the need to specify a priori whether flows in any part of the domain are laminar or turbu lent. Turbulent porous media flows can be simulated. The model is verified for porous-media and clear-fluid flows separately, before being used to simulate coupled groundwater - surface water flow scenarios. For porous-media flows with low Rep the numerical model results agree exactly with Darcy’s Law. The value of Rep at which the model results begin to deviate from Darcy’s Law is consistent with published values. For turbulent clear-fluid flows the time-averaged velocity and turbu lent kinetic energy (TKE) results from the numerical model are ver ified against a RANS model and published data. A good match is achieved for both velocity and TKE. Energy grade-line slopes for free-surface flows simulated in the numerical model are a reasonably good match to equivalent results to the one-dimensional hydraulic model HEC-RAS. Idealised river-aquifer interaction experiments are conducted in a lab- oratory flume to provide verification data for the numerical model. An innovative combination of optical flow measurement and refractive- index-matched transparent soil is used to measure two-dimensional velocities and turbulent statistics in laboratory flow scenarios that simulate flow in both losing and gaining streams, and the underlying connected porous layer. The “gaining stream” laboratory scenario is replicated using the numerical model. The model simulates the key features of the mean flow well. Turbulent statistics deviate substantially from the laboratory results where vertical velocities across the surface-subsurface interface are high, but are a better match elsewhere. The “losing stream” laboratory results are unable to be reproduced with the numerical model. Results for a similar scenario with lower outflow velocities are presented. These results are qualitatively consistent with the laboratory results. The numerical model is expected to perform better in simulations of field-like conditions that involve less extreme gradients than the laboratory scenarios.

    View record details
  • Gender, class and modernity : reproductive agency in urban India.

    Kohli, Ambika (2017)

    Doctoral thesis
    University of Canterbury Library

    The decreasing female child sex ratio in contemporary India is often linked to the small family norm. However, the decline of sex ratio has raised interesting questions regarding women’s involvement in decision making in the context of female-foeticide and managing family size. Are women victims or actors while making their reproductive choices? What are their reproductive interests, and how do they achieve them? This study investigates how urban-middle class women from Delhi and Haryana make reproductive decisions in regards to family formation in modern urban neoliberal society. Motherhood, abortions, and gender relations are discussed with reference to the main themes of son-preference, increasing social status of daughters, family planning, family building strategies, reproductive health and well-being. Further, because of the prevalence of son-preference it is crucial to understand what kind of status daughters are accorded in contemporary urban Indian society. This study addresses this by looking at participants’ differing perceptions and expectations for their daughters and sons, and in particular how daughters are treated. The status of daughters is documented through an examination of current forms of gender discrimination against them, and also the different kinds of opportunities that they are provided by their parents. These issues are explored through a qualitative study of the reproductive decision making of 45 educated married urban middle-class mothers from Delhi and Yaumuna Nagar (region of Haryana), India. Snowballing was used to recruit participants, and the fieldwork was carried out during two visits to India. I chose Delhi and Haryana because both of these regions have collective and patriarchal family structures. For instance, in these regions joint families are quite common among the middle-class and fathers or a male family member are often the head of the family. Furthermore, Delhi and Haryana have a low female child sex ratio, as recorded in the 2011 census, but have shown slight improvement in comparison to 2001 figures. Therefore, this study will provide insights into how women practice their reproductive agency in highly collective and patriarchal settings of their affinal families. These families are in the process of rapid socio-cultural changes, including change in gender roles and opportunities for daughters. I will examine women’s decision making process, including practices of negotiating and resistance strategies they develop. xvi I will then discuss how women engage with different forms of modern, spiritual and traditional technologies in order to maintain their reproductive health and well-being, and how they attempt to give birth to a son while maintaining the norm of small family size. This will suggest that society and technology are mutually constitutive. Finally, I will explore how social transformation has influenced the gender relationships which are discussed in relation to daughters’ improving status and also the different forms of discrimination currently used against them. However, throughout the research the patriarchal nature of urban neoliberal Indian society and the idea that a man is needed to support a woman and for her protection has been highlighted.

    View record details
  • The effects of soaking almonds on consumer acceptance and gastrointestinal tolerance

    Taylor, Heidi (2017)

    Masters thesis
    University of Otago

    Background: Nuts have a favourable nutrient composition and are an important part of a cardio-protective diet. Nuts are also high in phytate, which can reduce the bioavailability of nutrients and can be problematic for digestion. Recently, the recommendation to soak nuts to reduce phytate levels and improve gastrointestinal tolerance, has received much attention in the popular press. Unfortunately, there is no scientific evidence to support or refute soaking as a method for phytate reduction in nuts. Soaking is time-consuming, and pre-soaked products are expensive, so these claims may act as a barrier to nut consumption, which is already low within the New Zealand population. There is also no data on the acceptability of soaked nuts. The aim of this study was to assess the effect of soaking almonds on consumer acceptance and gastrointestinal tolerance. Methods: Seventy-six healthy participants were recruited from the Dunedin area to participate in an 8-week randomised crossover trial consisting of four treatment arms: 1. sliced soaked almonds, 2. sliced unsoaked almonds, 3. whole soaked almonds and 4. whole unsoaked almonds. Participants ate 30 grams/day of each nut treatment for 12 days in balanced random order. Each day participants rated their “overall liking”, “desire to consume”, and “likelihood of future consumption” of the nuts on 100 mm visual analogue scales (VAS). They also indicated the daily occurrence of gastrointestinal symptoms, and rated severity of any symptoms on a 100 mm VAS. Results: The sliced soaked almonds were rated significantly lower on all three acceptance scales compared to all of the other treatments (all P0.520). Overall, the ratings for all four treatments remained relatively stable across the 12-day period for each scale, and all mean ratings were above the midpoint. There were no significant differences in the incidence of any of the seven gastrointestinal symptoms between the four nut treatments (all P>0.174). The only significant difference for mean severity of symptoms was for flatulence, with whole soaked nuts rated significantly more severe than whole unsoaked nuts (0.59 cm vs 0.36 cm, P=0.005). Overall, the mean incidence and mean severity of all seven symptoms was very low. Conclusions: Our results suggest there is no evidence to support the recommendation to soak nuts prior to consumption as a means of improving gastrointestinal tolerance or consumer acceptance. The relative stability of the acceptance ratings, regardless of treatment, suggests nuts are resistant to monotony. It is encouraging that the majority of participants did not experience any gastrointestinal symptoms during the study, and mean overall severity was very low, indicating nuts are well tolerated by most people. Taken together, the acceptance and gastrointestinal data suggest that the recommendation to eat nuts regularly is realistic and achievable. Future research should focus on the effect soaking has on the phytate levels and nutritional composition of nuts.

    View record details
  • Bird fossils from the Takatika Grit, Chatham Island, New Zealand.

    Blokland, Jacob Christopher (2017)

    Masters thesis
    University of Canterbury Library

    View record details
  • Carbon and root system architecture : key regulators in nitrogen uptake in Lolium perenne L. and Brassica napus L.

    Guo, Qianqian (2017)

    Doctoral thesis
    University of Canterbury Library

    Nitrogen (N) is an essential macronutrient that limits plant yield and productivity. In order to increase crop yield, considerable amounts of nitrogenous fertilizers are applied to agriculture systems each year. However, about 25-70% of the applied fertilizer in ecosystem has been leached and released to the environment, in the form of NO, N₂O and NH₃, aggravating environmental pollution. Therefore, increasing nitrogen use efficiency in agriculture systems is essential to maintain the food production while alleviating the deleterious environmental effects of applied N. The mechanisms linking C/N balance to N uptake and assimilation are central to plant responses to changing soil nutrient levels. Defoliation and subsequent regrowth of pasture grasses both impact C partitioning, thereby creating a significant point of interaction with soil N availability. Using defoliation as an experimental treatment, the dynamic relationships between plant carbohydrate status and NO₃⁻-responsive uptake systems, transporter gene expression and N assimilation were investigated in Lolium perenne. High- and low-affinity NO₃⁻ uptake were reduced in an N-dependent manner in response to a rapid and large shift in carbohydrate remobilization triggered by defoliation. This reduction in NO₃⁻ uptake was rescued by an exogenous 1% glucose supplement, confirming the carbohydrate-dependence of NO₃⁻ uptake. The regulation of NO₃⁻ uptake in response to the perturbation of plant C/N was associated with changes in expression of the nitrate high-affinity transporter LpNRT2.1b. Furthermore, NO₃⁻ assimilation appears to be regulated by the C/N balance, implying a mechanism that signals the availability of C metabolites for NO₃⁻ uptake and assimilation at the whole-plant level. This study also shows that cytokinins are involved in the regulation of nitrogen acquisition and assimilation in response to the changing C/N ratio. Root architecture is also a crucial component that impacts the capacity of plants to access nutrients and water. By using the recently developed package RootNav, comprehensive morphological changes in root system architecture in response to different N sources were investigated in Brassica napus. In order to avoid a light-induced morphological and physiological responses affecting whole plant growth, an existing solid agar vertical-plate system was modified so that to allow roots to be shielded from light without sucrose addition and the emerging shoot to be grown without direct contact with the medium, thereby mimicking more closely the environmental conditions in nature. The results of 10-days-old B. napus seedlings showed that total root length, LR density and root exploration area decreased with increasing external NO₃⁻ concentrations from 0.5 mM to 10 mM. The application of 0.5 mM NO₃⁻ induced more branching in the root system relative to the treatments with higher N concentrations (5 mM and 10 mM). The proportion of biomass allocation occupied by roots was greater in the low NO₃⁻ treatment relative to the high NO₃⁻ treatments, reflecting the fact that plants invested more resources in their roots when nutrient uptake from the environment was limited. In treatments of increasing NH₄⁺ concentration from 0.5 mM to 10 mM, primary root length, total root length, LR branching zone, LR density and root exploration area were reduced. These results indicated that NH₄⁺ toxicity usually leads to a stunted root system in B. napus, whereas a low concentration of NH₄⁺ is an optimal nitrogen resource for plant growth. Increasing L-glutamate concentration from 0.01 mM to 0.1 mM suppressed primary root length, whilst the LR branching zone did not change in the different L-glutamate treatments, suggesting that L-glutamate even at micromolar level could arrest primary root growth and LR branching in B. napus. By using in situ ¹⁵N isotope labelling, morphological and molecular phenotypes generated pharmacologically were employed to investigate whether the impacts of contrasting root traits are of functional interest in relation to N acquisition. Brassica napus L. were grown in solid medium containing 1 mM KNO3 and treated with cytokinin, 6-benzylaminopurine, the cytokinin antagonist (PI-55), or both in combination. The contrasting root traits induced by PI-55 and 6-benzylaminopurine were strongly related to ¹⁵N uptake rate. Large root proliferation led to greater ¹⁵N cumulative uptake rather than greater ¹⁵N uptake efficiency per unit root length. This relationship was associated with changes in C and N resource distribution between the shoot and root, and in expression of BnNRT2.1. The root/shoot biomass ratio was positively correlated with ¹⁵N cumulative uptake, suggesting the functional utility of root investment for nutrient acquisition. These results demonstrate that root proliferation in response to external N is a behaviour which integrates local N availability and systemic N status in the plant. In conclusion, using two major economic forage species, L. perenne and B. napus, this thesis illuminates the impacts of carbon and root system architecture on N uptake. This work contributes to our understanding of the mechanisms regulating N uptake and will help further in efforts to improve nitrogen use efficiency.

    View record details
  • The effects of sub-lethal concentrations of biocides copper, pyrethrins and atrazine on antibiotic tolerance of Escherichia coli.

    Jun, Hyun (2017)

    Masters thesis
    University of Canterbury Library

    Biocides are used in different stages of crop production as herbicides, insecticides and fungicides. The toxicological mechanisms of these chemicals on their target organism is known, however, their sub-lethal effects on microbes are not. Previous work from this laboratory had shown that commercial formulations of herbicides can change the susceptibility of bacteria to antibiotics upon concurrent exposure. This is most likely due to changes in the expression of genes involved in influx and efflux and hence a physiological effect, reversible without requiring mutation. Out of the 12 combinations of biocide formulations and antibiotics tested, nine exhibited statistically significant differences in the minimum inhibitory concentration (MIC) between treatments in the presence and absence of biocides. The strongest effect was a greater than 30- fold change in MIC following exposure to copper and tetracycline. Where changes in susceptibility due to biocide exposure were observed, minimum inducing concentrations were identified from dose response curves. All observed effects were induced by biocide concentrations lower than the recommended application rate. The formulation had no observed effect on mutation frequency and the change in susceptibility was displayed uniformly by the population. Thus the effects on phenotype are consistent with adaptive resistance. To test whether efflux pumps were indeed responsible for the observed effects, different pump mutant strains were tested for the effect of copper on tetracycline resistance. The tolerance to tetracycline and copper in the pump mutant strains were significantly lower than the wildtype, indicating that the pump contributes to intrinsic resistance to both substances. In the mutant strains, copper exposure increased the tetracycline MIC 3 to 5 folds. This indicates that the AcrAB-TolC efflux system is not the only contributors to adaptive resistance. The persistence of the elevated tetracycline tolerant phenotype in the absence of copper fungicide was quantified. Although reversible, the induced phenotype was heritable for approximately 1 generation and the population uniformly reverted to a susceptible phenotype in the second generation post exposure. Continuous exposure to copper and tetracycline induced a morphological change in most or all exposed bacteria. The morphology changes included filamentation and then return to single cells, depending on exposure time. The morphological changes did not correlate with changes in genotype because the frequency of acquired resistance did not change. Dilution and re-growth experiments were used to determine whether the single cell form was outgrowth of a minority population or arose from filaments. The source of single cells was determined to be filaments.

    View record details
  • Tourism’s impact on the environment : a systematic review of energy and water interventions.

    Paul-Andrews, Leroy (2017)

    Masters thesis
    University of Canterbury Library

    The purpose of this research was to examine longitudinal assessments of the ways in which behavioural and policy interventions have been used to reduce energy and water use in tourism. Although previous research has used single-shot cases or surveys to study interventions there is little knowledge of the extent to which interventions result in sustainable personal or organisational behaviour over time. Therefore this thesis specifically focuses on identifying those studies in the literature that are longitudinal in nature to gain a better understanding of sustainable behaviour change. A systematic review was conducted to identify relevant studies. The systematic search returned a total of 333 papers relating to energy use, and 430 papers relating to water use. After screening and reviewing those returned papers against a predetermined, and specific criteria, only two papers relating to each topic remained. The two papers for each topic were then analysed and specific factors noted. The most effective outcomes of the energy papers were that of investing in modern, efficient technologies, and that of investing in and managing education of staff. The most effective outcomes of the water papers were again that of upgrading to modern, water-efficient equipment, and effective management of water resources. However, a critical finding was the absence of longitudinal studies of interventions which raises significant questions regarding the helpfulness of previous findings based on one-shot studies alone. The research was also the first of its kind looking at long-term interventions within sustainable tourism, and provides many avenues for future research.

    View record details
  • Integrated response as a process for enhancing the incident command system

    Fakuade, Dolapo (2017)

    Doctoral thesis
    University of Canterbury Library

    The devastating societal impacts of disruptive events have emphasised the need for more effective and unified emergency response arrangements. While policies that guide strategies, measures or approaches are not lacking in the emergency sector, they tend to be inadequate for response and relatively ineffective during response to large-scale or unprecedented events. This research critically examines theoretical bases and practice systems for emergency response, in order to identify useful community functions which can be integrated with emergency management response. The aim is to develop an integrated response framework that can be adopted to improve response to disruptive events. The data for this research were gathered through case study analyses of communities in Christchurch, which provided context for and helped define the scope of community functions required for emergency response. Data were also collected in semi-structured interviews and focus group sessions with different community groups and organisations, emergency management professionals, and officials working in Christchurch City Council. The analysis indicates that relevant functions exist within communities, and that four types of community functions can be used for improving emergency management response. Community functions identified were seen to possess relationships, interactions and qualities lacking in the emergency sector; characteristics that are essential for operational command and control response processes. The major research outcome is the development of a framework that integrates community functions with command and control structure as a contribution to improving response to disruptive events.

    View record details
  • The population of unresolved pulsars explanation of the Galactic Center excess.

    Ploeg, Harrison (2017)

    Masters thesis
    University of Canterbury Library

    It has been suggested that a population of unresolved millisecond pulsars (MSPs) could explain the observed Galactic Center Excess (GCE). However, it has been claimed that, based on the luminosity distribution of observed MSPs, many would already have been resolved. In this work, gamma-ray MSPs detected by the Fermi Large Area Telescope (Fermi-LAT) and the GCE data are used to constrain the luminosity function through the use of a Markov chain Monte Carlo (MCMC) algorithm. The results indicate that it is indeed possible that a population of unresolved MSPs with the same luminosity distribution as those observed are the source of the GCE and that it would require further improvements in sensitivity for these to be resolved.

    View record details
  • Understanding Tsunami hazard knowledge and preparedness : before and after the 2010 Tsunami in Mentawai (Indonesia)

    Panjaitan, Berton Suar Pelita (2017)

    Doctoral thesis
    University of Canterbury Library

    This thesis is about the people from the Mentawai Islands (in Indonesia) in the context of disaster risk reduction. It results from a curiosity to deeply explore the tsunami hazard knowledge existing before the 2010 Mentawai tsunami occurred, and current tsunami preparedness. It also provides theoretical frameworks and key research concepts in relation to the issues. In order to understand the picture of Mentawai in the past and the present, the thesis also includes how the tsunami vulnerability progression has been formed. The progression presents from the era of solitary lives of the people, the era of destroying the traditional beliefs and tools, and up to the current era when the people live in unsafe locations. In order to obtain a full picture of the topics, a qualitative case study was designed with the consideration of how to plot and to show a number of illuminating facts. The people’s reflections and perspectives on their tsunami hazard knowledge before the 2010 tsunami occurred and devastated the islands, and their current tsunami preparedness, were examined. There were a number of substantial facts showing how the research participants captured, shared, and internalized explicit knowledge on tsunami hazards into their tacit knowledge. These processes occurred with little support from the district government and local non-government organizations, and were further impacted by their low socio-economic and educational status. The processes of the knowledge internalization were obviously influenced by their traditional beliefs and personal perceptions. Thus, the implications of the internalization were also different when it came to anticipating tsunami waves. Subsequently, the 2010 tsunami also brought different impacts to the participants. In the context of current measures, tsunami preparedness is applied differently at various levels, even though the people have experienced the 2010 tsunami. At the individual level, the participants mostly ignore their own preparedness, although some of the participants have specific personal efficacy and protective behaviour to avoid tsunami waves. At the household level, some would most likely leave their household members to save themselves, while others would try to help their family members. At the sub-village (dusun) level, the people tend to abandon the evacuation processes. Meanwhile, at the district level, although some important documents exist for the district government to follow, tsunami preparedness measures are less prioritized. The last parts of the study are how the local community of Mentawai can increase their capacity to encounter potential tsunamis. In the absence of modern technologies, the community has a number of traditional strategies to anticipate hazards and various opportunities to reduce their vulnerability. Developing coping capacity is essential for the people through implementing community early warning systems. These systems will provide risk knowledge, strategies to monitor the surroundings, understandable warning communication, and qualified response capability in the event of a tsunami. For the longer term, the leaders and the community need to work hand in hand to create an adaptive mechanism for living in Mentawai. This will be achieved by utilizing and reutilizing their traditional tools and strategies, and taking any opportunity to improve their livelihoods, and consequently, their coping and adaptive capacities to deal with tsunamis.

    View record details
  • A descriptive study of how teachers identify and respond to children's challenging behaviour in early childhood education settings.

    Koh, Glorianne Elizabeth (2017)

    Masters thesis
    University of Canterbury Library

    Children’s challenging behaviour appears to be increasing with teachers reporting that they require additional knowledge and skills to address this problem. There also appears to be very little research on the strategies teachers currently use to address this behaviour. The aim of this study was to examine how eight teachers identified and responded to children’s challenging behaviour in four different early childhood education (ECE) settings, and directions for future professional development. Data was collected via a mixed method design that included two-hour direct observation of the teacher during a typical day and individual teacher interviews. The findings indicate that all eight teachers identified both externalising and internalising challenging behaviours and referred to the child’s social environment as contributing to challenging behaviour. All teachers indicated a range of strategies to address the challenging behaviour and identified these as having learned through experience, professional development and trial and error. Little reference was given to their ECE teacher training or to the early childhood curriculum, Te Whāriki, indicating a gap between theory and practice. For these teachers, future professional learning and development programmes could provide more emphasis on bridging the gap between theory and practice in terms of responding positively to children’s challenging behaviour in early childhood education (ECE) settings.

    View record details
  • The co-creation of gamified fitness experiences

    Hawkins, Tess E. (2017)

    Masters thesis
    University of Canterbury Library

    This thesis aims to investigate the different motivations of fitness technology users. Specifically, this thesis examines technology-based fitness experiences and the motivations and value that users derive from these experiences. Three literature streams are used to explain user engagement in technology-based fitness experiences: experience marketing, co-creation and gamification. In order to understand user motivations and the value derived from using this type of technology, an online survey was created using Qualtrics and a sample was recruited through Mechanical Turk. The scales used in the survey were sourced and adapted from the co-creation and gamification literature streams. A total of 360 responses were collected, and statistically analysed using multivariate procedures, including factor analysis and cluster analysis. On the basis of this analysis, users were put into distinct groups and profiled. The results revealed that functional, social and emotional value are significant sources of motivation for engaging in technology-based fitness experiences. It was also found that gamification is a significant area of value for users and, therefore, is as an important consideration for fitness app designers. The most relevant and influential constructs, in relation to technology-based fitness experiences and product usage co-creation, were also identified. These include the risk and accessibility components of the DART framework and the four factors of the mobile Internet experience. In contrast, personalisation and flow were identified as unimportant to users. It was found that users predominantly utilise fitness apps to help meet their need to achieve fitness and health related goals. However, it was also identified that the gamification aspects of fitness apps are highly valued by users. This study demonstrates that fitness app designers must endeavour to make their apps functional and entertaining as it will likely elicit user adoption.

    View record details
  • BYOD (Bring Your Own Device) and its impact on teacher pedagogy: a New Zealand case study

    Rae, Genevieve (2017)

    Masters thesis
    University of Canterbury Library

    The practice of students bringing their own device to school BYOD (Bring Your Own Device) has now become reasonably common in New Zealand primary schools after being first introduced in the late 1990s. It has become a strategy that schools can use to provide 21st century learning opportunities for students without having to provide school-­‐owned devices. This study raises important questions for teachers and schools to ask themselves before implementing BYOD. This study explores the experiences of three New Zealand primary school teachers as they introduce BYOD into their classrooms. The case study sought to understand what factors impacted on their ability to implement new pedagogical practices and how professional learning might help support teachers with BYOD. The literature review examines national and international literature on the implementation and impact of BYOD. It discusses how and why teachers do or do not engage with ICT in classrooms and how BYOD impacts on their practice. This case study utilises SAMR (Puentedura, 2006) and TPACK (Mishra & Koehler, 2006) in order to analyse the data and discuss the findings. The findings suggest that, in order for teachers to maximise the potential of BYOD, professional learning and technical support is essential. The teachers experienced a number of challenges as they introduced BYOD, yet all managed to persevere and remain positive as they trialled new teaching methods, and utilised new programs and applications. The study concludes by making a number of pertinent recommendations that can be actioned by schools in order to ensure implementation is smooth and successful. It is very important that teachers are supported adequately by the school and are given opportunities to engage in relevant and timely professional learning.

    View record details
  • Phenological, physiological, and ecological factors affecting the epiphyte Notheia anomala and its obligate host Hormosira banksii

    Metcalfe, Isis Hayrunisa (2017)

    Masters thesis
    University of Canterbury Library

    Notheia anomala is an obligate epiphyte commonly found on the abundant habitat-forming alga Hormosira banksii in intertidal areas throughout temperate Australasia. The tight co-evolved relationship between these species is unique because: (i) Notheia is a true obligate epiphyte, which is uncommon in the marine environment, (ii) the order Fucales is over 70 million years old and includes over 10 families, but Notheia is one of few fucoid epiphytes, and (iii) phylogenetically close species are rarely so closely linked (Hormosira, the obligate host of Notheia, is also a fucoid). This project is the first to address the phenological, physiological, and ecological factors affecting the Notheia-Hormosira relationship through a combination of field surveys and manipulative experiments. Phenological observations indicated that the two species may have asynchronous life cycles. I found that Notheia reproduction peaked in April (Austral autumn) when seawater temperatures were mild, whereas previous studies have shown peak reproduction in Hormosira during the period July to October (Austral winter/spring). There were differences in the development of Notheia conceptacles across different habitats (high shore areas, low shore areas and tide pools). Conceptacles developed faster, and were at full maturity for longer in the tide pool habitat. It is likely that lower levels of desiccation stress in tide pools allow faster conceptacle development and longer periods of reproductive maturity. From an evolutionary and ecological perspective, it is expected that the distribution of Notheia should closely resemble that of Hormosira across spatial and temporal scales. To test this, I compared distribution patterns of Hormosira and Notheia from the large continental scale to the small individual host plant scale. While Notheia biogeographical distribution is intricately linked to its host Hormosira, I found contrasting ecological habitat preferences, with tide pools hosting the lowest abundance of Hormosira and the highest abundance of Notheia respectively. At the host plant scale, I found that Hormosira plants from the high shore had the greatest number of Notheia clumps attached near the low-holdfast region. In the low shore and tide pools the pattern was opposite, with most Notheia clumps attached to the mid and high regions of the host. Notheia was equally likely to be found attached to male and female host plants, and more epiphytes were found attached to older than younger host plants. Using field tagging and translocation experiments, I also quantified the survival and growth of Notheia at different densities exposed to various stressful environmental conditions. Tagged Notheia clumps, with different plant densities and sizes, from the low shore and tide pools all experienced high mortality over a five-month period associated with high dislodgement rates of the host Hormosira. In translocation experiments of Notheia fronds (without its host), I found that individuals translocated to the high shore experienced close to 100% mortality, suggesting that desiccation and possibly photo inhibition are the main factors limiting the upward distribution of Notheia. Translocations to the low shore and tide pools demonstrated that Notheia fronds can survive and grow detached from its obligate host and suggest that the obligate dependency is most likely an early life stage requirement. Finally, I tested whether the abundance of invertebrate inhabitants associated with Hormosira varies in the presence of Notheia across spatio-temporal scales. Field surveys showed that, as predicted, there were strong positive density-dependent effects of Notheia on both richness and abundance of invertebrates, regardless of the spatio-temporal context and resident invertebrate taxa, providing one of the first examples of a habitat cascade occurring in rocky intertidal systems. Through a recolonization experiment, I tested whether invertebrate abundance was driven by (1) Notheia or Hormosira, (2) high or low amounts of Notheia and (3) living Notheia fronds or abiotic mimics. Hypotheses 1 and 2 were strongly supported, with more biomass of Notheia (as opposed to Hormosira) supporting more invertebrates, but not Hypothesis 3, as richness and abundances of inhabitants were similar between living Notheia fronds and artificial mimics. This suggests that Notheia is primarily providing habitat rather than food to the invertebrate inhabitants. Based on these results I hypothesized that invertebrates exert little or no grazing pressure on Hormosira and Notheia. This was tested in a laboratory food choice experiment focusing on potential grazing effects from herbivorous gastropods. In contrast to this hypothesis, I found negative effects of gastropods on both Hormosira and Notheia, with stronger grazing on Notheia. However, grazing rates were low overall and are likely to play only a minor role in regulating the abundance and distribution of the two species under natural field conditions. In support of the spatio-temporal surveys and colonization experiment, the grazing experiment also suggests that Notheia provide a better habitat for small invertebrates than Hormosira. Seaweeds are key components of coastal ecosystems, providing habitat and food for a wide range of marine organisms. Therefore, understanding their life history patterns and reproduction dynamics is essential for managing coastal areas and assessing ecosystem health. This study is the first to explore the long-term phenology and periodicity of reproduction in Notheia. Furthermore, my results support a growing number of habitat cascade studies from different ecosystems, and suggest that these processes are common in marine benthic systems.

    View record details
  • Estimating leaf area index from airborne laser scanning.

    Pearse, Grant Dennis (2017)

    Doctoral thesis
    University of Canterbury Library

    Leaf area index (LAI) quantifies the amount of leaf surface area per unit ground area. LAI in forest ecosystems regulates the upper limit of possible light interception, atmospheric gas exchange, and primary production. These properties make LAI one of the most important ecophysiological variables with a wide range of potential applications. In the context of forests managed for production, knowledge of LAI offers the potential to align management activities with fundamental biophysical properties. For example, LAI offers the potential to precisely target and monitor management activities such as fertiliser application or disease control. Despite the potential benefits knowledge of LAI offers, usage is seldom seen outside of research applications. A key reason for this is the difficulty in obtaining LAI measurements over large areas, with field based optical methods largely constrained to use under uniform, diffuse sky conditions. Remote sensing of LAI offers one potential solution to obtain large-scale estimates of LAI. However, promising spectral-based approaches have been shown to have limited usefulness for forests with high LAI such as intensively managed coniferous plantations. Airborne laser scanning (ALS) data (lidar) offers enhanced ability to estimate LAI in a range of forest types with a high degree of accuracy, but the optimum methods for estimating LAI from lidar are not well established. This thesis aims to develop and demonstrate a method for estimating LAI from lidar in New Zealand’s intensively managed Pinus radiata D. Don forests. To accomplish this, two distinct areas of research are addressed. First, this thesis addresses the need for acquiring a large number of LAI field measurements covering a range of stand conditions in order to calibrate ALS-LAI models. This was accomplished by validating the use of the newly developed LAI-2200C (LI-COR Biosciences Inc., Lincoln, NE, USA). This instrument allows measurement of LAI under clear sky conditions through the application of a model to correct for the impact of scattered light on gap fraction estimates. This thesis presents the first in situ comparison of LAI measurements acquired under diffuse and clear sky conditions in a coniferous forest. These results were obtained by repeatedly measuring LAI in plots of pure P. radiata in New Zealand. In addition, the thesis presents the first assessment of the importance of acquiring accurate needle spectra to parameterise the scattering correction model. These values were acquired using newly developed methods that allow accurate spectra to be acquired from needle-leaved species via spectroradiometer. The thesis also addresses the stability of needle optical properties with respect to position in the canopy, abaxial and adaxial measurements, and variability between individual trees. The second part of this thesis used a large number of LAI measurements made possible by the new instrumentation to address key questions on the topic of estimating LAI from lidar. To date, most ALS-LAI research has been divided between establishing empirical or physical links between lidar metrics and LAI. This has resulted in a proliferation of proposed methods and lidar metrics for estimating LAI, and few studies have compared these approaches. In addition, factors known to impact ALS-LAI estimation such as the choice of plot parameters have gone relatively unexplored, as has the use of new statistical learning approaches. This thesis attempts to offer the first simultaneous assessment of the optimum combination of lidar metrics, plot parameters, and modelling approaches for estimating LAI from ALS lidar data in P. radiata forests. Results from the instrument validation suggest that the scattering correction model performs well in coniferous forests. Overall, clear sky LAI measurements were higher on average than diffuse sky measurements. However, there was evidence that this difference resulted from a reduction in erroneous readings obtained from the largest outer sensor ring under diffuse sky conditions. Traditionally, data from this part of the instrument have been error-prone and there was some evidence that clear sky LAI measurements offer increased accuracy by reducing scattering induced error across the range of zenith angles observed by the instrument. The method used to obtain spectroradiometer measurements from needle-leaved specimens was well suited to collecting accurate needle reflectance and transmittance for use in the scattering correction model. Use of these values improved agreement between clear and diffuse sky LAI measurements and reduced the magnitude of the largest differences at the extremes of the range. The results demonstrated that P. radiata spectra did not differ significantly with canopy position and were reasonably stable between trees. Measured P. radiata needle spectra are presented as part of this thesis and values are suggested for future users of the LAI-2200C scattering correction model in this forest type. Overall, use of measured spectra in combination with masking of outer ring data allowed LAI to be measured under both clear and diffuse sky conditions; however, clear sky conditions offered considerable reductions in the maximum potential measurement error resulting from changes in sky condition over time and between sensor locations. Results presented in the second part of this thesis demonstrate that LAI can be accurately estimated from lidar data in P. radiata forests. A key finding from this work was that use of standard approaches developed for use in other forest types produced some of the worst models of all those trialled, indicating that successful ALS-LAI estimation in P. radiate depends on careful selection of lidar metrics, plot parameters, and modelling approach. Specifically, results showed that (1) metrics that form a proxy for gap fraction by computing the ratio of returns above and below a chosen height threshold (ratio metrics) were key predictors of LAI; (2) choice of height threshold for ratio metrics strongly impacted model performance and P. radiata appeared to require higher thresholds than other forest types; (3) the concept of a variable height threshold was beneficial in accommodating differences in tree height across plots and led to improved estimates of LAI; (4) a larger fixed plot radius generally improved model performance; (5) use of a variable plot radius linked to instrument view distance was better than any fixed radius trialled; (6) metrics linking lidar penetration to the Beer-Lambert law were only marginally less accurate than empirical models and showed strong predictive ability. This approach may offer a means of estimating LAI without calibration by inverting the Poisson model using gap fraction from lidar and an empirical projection coefficient. Finally, the research found a high level of correlation present between lidar metrics, strongly emphasising the need for modelling approaches robust to these effects. Regularised regression via the elastic net was found to be a useful method for providing both variable and model selection in high-dimensional space while accounting for the presence of high correlation between metrics. Results from models produced by the random forests algorithm were similar to results from elastic net but provided some useful insights into variable importance.

    View record details
  • Investigations into sulfamide as a phosphate isostere in anti-TB drug development.

    Suthagar, Kajitha (2017)

    Doctoral thesis
    University of Canterbury Library

    Two major oligosaccharides, lipoarabinomannan (LAM) and arabinogalactan (AG), are important constituents of the cell wall of Mycobacterium tuberculosis, the causative bacterial pathogen of tuberculosis. The AG, which is attached to long chain lipids, provides a very effective hydrophobic barrier against the penetration of anti-mycobacterial drugs. The LAM and AG consist of varying numbers of arabinofuranose residues. The biosynthesis of the arabinan portion of both is postulated to involve multiple arabinofuranosyltransferases (AraT's), which catalyse the step-wise coupling of the donor decaprenolphosphoarabinose (DPA) to growing oligosaccharides. We have synthesized a series of arabino glycosyl sulfamides as potential inhibitors of mycobacterial cell wall biosynthesis. In this work sulfamide was used as an isostere of phosphate and varied the hydrophobic substituents as mimics of the polyprenol chain of DPA. However, arabino N-glycosyl sulfamides, sulfonamides, and sulfamates unexpectedly and spontaneously converted from the furanose to the pyranose form in an aqueous solution. To remedy this, a series of glycosyl sulfamides which lacked the 5-hydroxyl group were synthesized in order to fix these materials in the furanose form. All compounds were synthesised and tested for anti-mycobacterial activity using the Alamar Blue (AB) assay. Compounds displayed low to moderate activity against M. smegmatis. The recently discovered enzyme Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt), catalyses the phosphorylation of thymidine monophosphate (dTMP) to give thymidine diphosphate (dTDP), and is indispensable for the growth and survival of M. tuberculosis, as it plays an essential role in the DNA synthesis. Therefore, inhibition of TMPKmt may be an attractive avenue for the development of novel anti-tuberculosis agents. Possible sulfamide structures were screened using in silico induced-fit docking methods as dTMP analogues with TMPKmt X-ray crystal structure (PDB accession code: 1N5K). From these docking results, a selection of compounds was synthesized and the evaluated for any anti-mycobacterial activity. However, none of the compounds showed promising inhibitory activity against M. smegmatis. A novel reduction method was accidentally discovered during the synthesis of 6-amino-D-mannose pyranose, using iodide and Amberlite IR 120 ion exchange resin (H⁺ form). During this process, D-mannose was first selectively iodinated using an Appel reaction, subsequent nucleophilic substitution using NaN3. Following that reaction, in order to remove the imidazole, the reaction mixture was filtered through Amberlite IR 120 ion exchange resin (H⁺ form), and then concentrated in vacuo. Interestingly, the final product was identified as the amine. As it is simple, efficient, and mild reduction method for the conversion of azides into amines, the reaction condition was optimized using NaI/Amberlite IR120 (H⁺ form), and tolerance of the functional groups also investigated.

    View record details