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  • ItemOpen Access
    Bus benefits, barriers, and behaviour: a look into perceptions of public transport in Waimakariri, and current travel behaviour and trends
    (2025) Hendrie, Ben
    Public transport is widely used globally, however in New Zealand, the usage is much lower than other countries. In this thesis, the topic of public transport for the purpose of commuting from the Waimakariri District into Christchurch City will be analyzed. The overarching research question for the project is “How can public transport in the Waimakariri District be improved for the benefit of residents commuting into Christchurch, and what trends exist within current commuting patterns”. This large research question will be answered through two smaller research questions. The first smaller research question is “what are the existing benefits and barriers that the Waimakariri Community face in utilizing public transport for commuting into Christchurch City”, and will be answered through a perceptions survey, and focus groups. The second research question will be “what are the existing trends and patterns in relation to where the Waimakariri Community commute using public transport”, and will be answered through a travel patterns survey, and data analysis of MetroCard data. These two questions are beneficial for the Waimakariri District Council, who is the community partner for this project.
  • ItemOpen Access
    Examining and addressing stigmatising attitudes of health professionals towards minor-attracted persons
    (2025) Campbell, Kelsey
    Individuals who experience sexual attraction towards children, often referred to as minor- attracted persons (MAPs), are a highly stigmatised population. Stigmatising attitudes, characterised by negative stereotyping, social isolation, and dehumanisation can have detrimental effects not only on the mental health of these individuals, but also on their willingness to seek help to access support services. Among health professionals, stigmatising attitudes and misconceptions can hinder their ability to provide effective, non-judgemental treatment for MAPs, potentially increasing the risk of offending in the future. The current study aimed to investigate the effectiveness of a brief informative video intervention in reducing stigma and increasing professionals’ willingness to provide treatment to MAPs. Using a mixed-subjects design, 28 participants were randomly assigned to either an intervention or control group. Both groups completed a survey measuring willingness to treat as well as stigma attitudes across subscales of dangerousness, intentionality, deviance and punitive attitudes, at two time points (initial testing and one-month follow up). Results revealed that participants in the intervention group reported lower stigma scores across all subscales with significantly lower scores across subscales of dangerousness and punitive attitudes at initial testing compared to the control group. The intervention group also reported significantly higher scores on the willingness to treat subscale at one-month follow up. These findings underscore the importance of specialised training for health professionals to address common areas of stigma and promote more empathetic, evidence-based responses when working with MAPs. While the small sample size limits the generalisability of the results, this study contributes to the growing literature promoting anti-stigma interventions as a means of contributing to reducing the risk of child sexual offending by increasing the availability of early, accessible, and effective care towards MAPs.
  • ItemOpen Access
    Maximising the socio-cultural benefits of urban blue green infrastructure to enhance urban liveability: a case study approach
    (2025) McNabb, Tyler
    Many contemporary urban communities are challenged by increased flood risks and rising temperatures, declining water quality and biodiversity, and reduced mental, physical, cultural and social wellbeing. The development of urban blue-green infrastructure (BGI), defined as networks of natural and semi-natural blue-green spaces which enable healthy ecosystem processes, has been identified as one approach to mitigate these challenges and enable more liveable cities. Multiple benefits associated with urban BGI have been identified, including reduced flood risk and temperatures, improved water quality and biodiversity, enhanced mental and physical wellbeing, strengthened social cohesion and sense of place, and the facilitation of cultural connections and practices. However, socio-cultural benefits have tended to be neglected in BGI research and design, resulting in a lack of awareness of how they may be maximised in BGI design. As such, this research sought to understand how BGI can best be designed to enable liveable cities. Four questions were considered: (i) what benefits are associated with urban BGI, (ii) how does the design process influence the benefits achieved by BGI, (iii) what challenges are encountered during BGI design, and (iv) how might the incorporation of communities and Indigenous knowledge into BGI research and design enhance current understandings and applications of urban BGI? To address these questions, a mixed methods case study approach was employed in Ōtautahi Christchurch and Kaiapoi. The four selected case studies were Te Oranga Waikura, Wigram Basin, Te Kuru and the Kaiapoi Honda Forest. The cases are all council owned urban wetlands which were primarily designed or retrofitted to reduce urban flood risks following the Canterbury Earthquake Sequence. To investigate BGI design processes in each case, as well as how communities interact with, value and benefit from these spaces. BGI projects were found to be designed by interdisciplinary design teams driven by stormwater engineers, landscape architects and ecologists which prioritised bio-physical outcomes. Further, community and Indigenous engagement approaches closely resembled consultation, with the exception of Te Kuru which employed a co-design approach between councils and Indigenous and community groups. This co-design approach was found to enhance current understandings and applications of urban BGI, while uncovering multiple socio-cultural values to be incorporated into design, such as access to cultural healing resources, increased community connections to water, and facilitating cultural monitoring methodologies and citizen science initiatives. Communities frequently identified the opportunity to connect with natural environments and enhanced mental and physical wellbeing as key benefits of BGI. Conversely, strengthened social cohesion, sense of place and cultural connections were infrequently identified as benefits, if at all. This finding indicates a disconnect between the bio-physical benefits which drive BGI design and the outcomes which communities value. As such, there is a need for future BGI design to more fully consider and design for socio- cultural outcomes to better enable liveable cities. To better design BGI to enhance urban liveability, this research makes three key contributions. First, there is a need to advance current approaches to transdisciplinary design to better account for the full scope of perspectives and values associated with BGI. Second, there is a need to transition towards relational co-design with Indigenous and community groups and knowledge. Third, it is important to continue to monitor, reflect on and share both positive and negative BGI design experiences to continually improve outcomes. The incorporation of social and cultural researchers, knowledges and perspectives into open and collaborative transdisciplinary design teams is identified as a key method to achieve these opportunities.
  • ItemOpen Access
    OCHT properties regional transportation accessibility analysis :how to improve tenants’ transportation efficiency and living experience?
    (2025) Wang, Haoze
    Transport accessibility is a key factor in urban planning, influencing regional economic development, community cohesion and residents' well-being. While transport accessibility has been widely studied in the academic field and has a certain importance in promoting sustainable urban development and social equity, there is still a certain gap in its impact on social housing communities and residents with difficult transport choices. Christchurch is characterized by a strong car culture, with private cars as the main means of transportation. However, 25% of the population in the Canterbury region has a disability and nearly 90% of OCHT (Ōtautahi Community Housing Trust) tenants do not have the ability to travel by private car. Many residents face travel difficulties and lack effective transportation options. This study adopted a mixed research methods approach, combining geographic information system (GIS) spatial analysis, QGIS web-based accessibility modelling, and secondary data analysis from OCHT and Christchurch City Council. Service area analysis and isochrone mapping were applied to quantify accessibility by different modes of transport, including walking, cycling, public transport, and driving. Meanwhile, accessibility to supermarkets, bus stops, clinics, parks, schools, and artworks near OCHT properties was assessed. In addition, demographic and housing data from OCHT provided context for interpreting accessibility constraints faced by tenants. The study aimed to: (1) assess the transport status of OCHT tenants, (2) analyse the accessibility of key amenities and transport infrastructure around OCHT properties, (3) identify strategies to enhance transport options and improve tenants’ living experience, and (4) inform future property allocation and development planning in OCHT. This study combined transport accessibility analysis with social housing research to develop accessibility profiles for each property, providing insights into potential differences in accessibility levels and infrastructure provision between different neighbourhoods and areas. And provides a quantitative basis for optimizing housing placement according to accessibility needs, ensuring improved living conditions for tenants, especially those with low incomes or limited mobility. By strengthening connections between OCHTs and their tenants, the research aims to support equal access to transport and infrastructure services, thereby promoting the development of more inclusive and resilient communities.
  • ItemOpen Access
    Taxonomy and conservation genomics of threatened limestone populations of Senecio aff. matatini (Asteraceae).
    (2025) Patel, Samiksha
    Senecio matatini is a recently delineated New Zealand endemic of the Astereceae family with four recognised subspecies. However, the existence of several morphologically deviating populations in limestone environments prompts the question of whether the limestone populations should be recognised as one or more subspecies of S. matatini or if they should be recognised as another one or more distinct species. These taxonomically ambiguous calcicolous plants are only known from small and isolated populations, which are considered to be declining. This further necessitates taxonomic research, as well as obtaining a better understanding of their patterns of genetic connectivity and diversity. We used genomic data obtained through Genotyping by Sequencing to determine the amount of genetic diversity in populations and the extent of connectivity among populations of six limestone forms of S. matatini - S. aff. matatini “Cape Campbell” , S. aff. matatini “Castle Hill”, S. aff. matatini “Mt Cass” (de Lange et al., 2018; Ornduff, 1960; Rogers et al., 2018), S. aff. matatini “North Dean”, “South Marlborough Limestone” and S. aff. matatini “Tablelands”. We also included representatives of the four currently recognised subspecies of S. matatini in my analyses - S. matatini subsp. basinudus (Ornduff) Courtney, de Lange & Pelser, S. matatini subsp. discoideus (Cheeseman) Courtney, de Lange & Pelser, S. matatini subsp. matatini and S. matatini subsp. toa (C.J.Webb) Courtney, de Lange & Pelser. We used landmark analysis on a subset of this species complex to help resolve some of the patterns of genetic structure. This was to determine how genetically distinct they are to the limestone forms. We aimed of identify limestone populations and forms that have unique genetic variation or are genetically isolated from other populations and forms. We also aimed to determine which and how many taxa to recognize within this taxonomically complex group. We found patterns of genetic structure within the species complex which showed the most support for five distinct genetic clusters with little admixture between the groups. The individual limestone entities hold unique variation further indicative of their genetic isolation. The limestone entities were not all distinct from the subspecies. The population genetic analyses found the limestone entities to hold high levels of genetic variation, however, metrics for some entities were influenced by low sample sizes. Taxonomic recognition for two new subspecies representing limestone entities is recommended. One limestone entity, thought to be unique clustered tightly with one of the subspecies. Other entities largely can be accommodated in the current taxonomic classification of S. matatini, however these may need further study. The results of this study will help inform the formal classification of the S. matatini complex, contribute to an accurate assessment of its conservation status, and facilitate effective conservation management.
  • ItemOpen Access
    LLM meets LLM : AI revolution in New Zealand's legal profession - exploring junior lawyers' experiences, curriculum alignment, and cultural implications.
    (2025) Ferguson-Lees, Finnegan Linus
    This study explores the impact of artificial intelligence (AI), particularly large language models (LLMs), on junior lawyers' work in New Zealand's legal profession. Existing research on AI in law primarily focuses on its technical capabilities, overlooking the lived experiences of legal professionals navigating this technological shift. To address this gap, this study employs a qualitative approach to investigate the essence of AI integration in legal practice and its psychological and practical effects on junior lawyers and their work. Ten semi-structured interviews were conducted with a diverse purposive sample of junior lawyers across New Zealand. Thematic analysis identified two major themes in junior lawyers' lived experience: Transforming Legal Practice and Opportunities and Challenges for Junior Lawyers, as well as an overarching theme of Te Tiriti o Waitangi (The Treaty of Waitangi), which is woven through all themes, sub-themes, and categories in this research. The findings focus on three key areas: the psychological and practical effects of AI on junior lawyers' work, the alignment between legal education and the emerging AI-driven profession, and the intersection of AI, law, and Māori customs, primarily Te Ao Māori (Māori worldview) and Tikanga (Māori customary law). Findings show that while AI can enhance productivity, it raises concerns about job security, ethical dilemmas, and the shifting of junior lawyers' roles from routine tasks to more complex, analytical, and interpersonal work. This study also identifies a significant disconnect between legal education and the realities of AI-integrated practice and uncovers the risks of AI perpetuating biases, particularly for Māori clients. This research contributes to understanding AI's impact on the legal profession in New Zealand, offering insights for legal educators, law firms, and policymakers. It emphasises the need for targeted training, ethical guidelines, and cultural sensitivity in AI implementation, paving the way for a more prepared and resilient legal workforce in the face of technological change.
  • ItemOpen Access
    Acculturation and its effects on cultural identity and wellbeing : an interpretative phenomenological analysis of Afghan women’s experiences living in Aotearoa New Zealand.
    (2025) Gentleman, A. L.
    Millions of people around the world flee their homelands due to persecution and conflict. As refugees in host countries, every single one of those people will undergo an acculturation process as they try to rebuild their lives within vastly different cultural contexts. Whilst there has been considerable research into resettlement stressors and their impact on mental health, far less is known about the long-term outcomes of the acculturation process on former refugee’s sense of cultural identity and wellbeing. Using Interpretative Phenomenological Analysis (IPA), this study explored the experiences of female Afghan former refugees who had been living in Aotearoa New Zealand for many years. Three common sub-themes emerged from their experiences of the acculturation process: overcoming obstacles, maintaining a cultural balance, and shifting gender power dynamics. Common sub-themes around cultural identity included: living out of cultural context, ‘losing’ one’s homeland, and making a new home. Participants described struggling through the acculturation process but then finding a cultural equilibrium which they maintained through a series of checks and balances. They all considered themselves to be Afghan-Kiwi but felt their personal identity had not changed, only how they identified culturally. Participants had created, both literally and metaphorically, a home within a home – the inner bastion was Afghan, and the outer walls Kiwi. Exploring participants’ retrospective experiences of resettling in a new country has helped deepen understanding of the acculturation process and its effects on cultural identity in the longer term. The sense of cultural integration and wellbeing felt by participants also served to highlight the positive impact that government policy and local non-governmental organisations can have on refugee and former refugee populations. By allowing participants to be heard in their own words, this study helps to relocate the focus of acculturation research back to the level of the individual and lends depth to other quantitative findings.
  • ItemOpen Access
    Tracing the chemical evolution of globular clusters.
    (2025) Sinclair-Wentworth, Heather
    1.1 Globular Clusters Globular Clusters (GCs) are dense, old stellar clusters, often containing hundreds of thousands of stars. They lie predominantly in the halo of the Milky Way (MW) but are also present in the bulge and thick disk with often extreme internal kinematics and metal-poor stars (Gratton et al. 2019). A robust definition of a GC is still being debated with many factors now taken into account such as the cluster mass, metallicity and which region in the galaxy the cluster belongs to, as well as investigations into chemical properties (Carretta et al. 2010). GCs were originally thought to be simple stellar populations, that is, they are comprised of stars with similar ages and abundances (Bastian and Lardo 2018). However, more complex chemical trends have been observed with large intra-cluster variations for many elements, indicating GCs can have multiple stellar populations (MSP). A prominent chemical feature of most GCs are the presence of anti-correlations. In particular, the sodium-oxygen (Na-O) and magnesium-aluminium (Mg-Al) anti-correlations (Gratton et al. 2001; Carretta et al. 2009b; Pancino et al. 2017b; Bastian and Lardo 2018). Na and O undergo more internal mixing in stars compared to Mg and Al, therefore, Mg and Al abundances have minimal dependance on a star’s evolutionary stage (Pancino et al. 2017b). This allows the Mg-Al anti-correlation to act as a tool for tracing the chemical enrichment history of GCs. The observed Mg and Al abundances reflect the contributions of previous generations of stars, unaffected by ongoing nucleosynthesis in the observed stars. However, clusters that do exhibit Na-O anti-correlations do not always show Mg-Al anti-correlations as well, therefore the Na-O anti-correlation can be utilised in more clusters to determine the existence of multiple populations (Bastian and Lardo 2018). There are two main theories of where GCs form, either they are part of their host galaxy’s initial formation, or they have formed externally to then be accreted into another galaxy (Gratton et al. 2019). External accretion has been supported by studying stellar morphology within clusters, and by counting the number of GCs in nearby dwarf galaxies, the Milky Way is proposed to have had approximately seven merger events with cluster-bearing dwarf galaxies (Mackey and Gilmore 2004). This would generate the roughly 41 external clusters as determined from Mackey and Gilmore 2004. A slightly wider range of 27-47 possible external clusters from 6-8 dwarf galaxies was found in Forbes and Bridges 2010. Today, the Milky Way is known to contain at least 151 GCs with the origin of some still uncertain (Massari et al. 2019). Spectroscopy is the study of starlight, often in optical or infrared wavelengths, to determine characteristics of stars such as their astrophysical parameters and chemical abundances. As GCs have a tight distribution of stars in the centre, it can be challenging to observe resolved stars in this region. Integrated light observations allow the study of stars within the cluster centre where multiple stars are observed at once in a single spectrum. However, individual stellar spectra can be obtained for stars that lie outside of this dense region. Spectroscopic observations of GCs can be undertaken by either obtaining integrated light spectra, or single stellar spectra where individual cluster members are observed. The chemical information obtained from examining spectra of GCs contains crucial information about the abundance of specific elements in the atmosphere of the stars. By observing many individual cluster stars, detailed intra-cluster variations can be explored to determine possible multiple populations and their origins. 1.2 Research Motivation The primary aim of this thesis is to investigate chemical trends within globular clusters (GCs) using the Gaia-ESO Survey (GES) (Gilmore et al. 2012; Gilmore et al. 2022; Randich et al. 2022) GC sample. Part of this is to assess if additional abundances can be determined to expand the sample. The GES GIRAFFE medium resolution and UVES high resolution spectra will be reassessed to determine if any additional chemical abundances can be measured using iSpec (Blanco-Cuaresma et al. 2014; Blanco-Cuaresma 2019). iSpec is a python wrapper around spectral synthesis codes and in this thesis, will be utilised with the synthesis code MOOG (Sneden et al. 2012). This method results in a synthetic spectrum created to be compared with the observed using a least squares fit. This fit is then minimised, producing the determined chemical abundances for the corresponding star. The analysis of these abundances will focus on the intra and inter-cluster chemical trends, investigating both individual clusters and the entire GC population. Specifically, the trends for elements that strongly represent an astrophysical process such as a nucleosynthesis and enrichment processes. These elements are also known as tracer elements and are crucial for understanding the underlying contributions to stellar formation within GCs. Using tracer elements can help to determine the existence of any multiple populations and generations of stars with GCs, and their typical chemical trends. A comparison to the wider Milky Way chemical evolution will also be performed to provide insight into how these clusters relate to the MW as a whole, as well as the detection of possible accreted clusters from other galaxies. The presence of any accreted clusters provides opportunity to examine extra-galactic GC abundance trends and implications. These abundance analyses will contribute to understanding the elusive characteristics of GCs. The secondary aim of this work is to investigate the capabilities of the University of Canterbury Ōtehīwai Mt John Observatory for GC analysis. This capability of the University of Canterbury Ōtehīwai Mt John Observatory will be tested by obtaining integrated light spectroscopy on the 1-metre McLellan telescope and the High Efficiency and Resolution Canterbury University Large Echelle Spectrograph (HERCULES). As with the GES spectra, iSpec will be used except this time, for the determination of astrophysical parameters such as metallicity and radial velocity. A comparison between the literature values of GCs observed and the derived parameters will be used to assess the quality of GC studies at Ōtehīwai Mt John Observatory. As the current observations on the 1-metre McLellan telescope are exclusively bright (V< 9), resolved targets, pushing the limit to fainter targets would provide new research opportunities and future programs. 1.3 Thesis Structure This thesis has the following structure. Chapter 2 discusses the background and theory of topics used in the thesis such as the chemical properties of stars and their application on the wider chemical evolution of the Milky Way galaxy. Chapter 3 outlines the methods, results and brief discussion of integrated light spectroscopy for two GCs obtained at the University of Canterbury’s Ōtehīwai Mt John Observatory. In Chapter 4, the spectral synthesis method for obtaining additional abundances from the Gaia-ESO Survey spectra is described. The abundance results from this are shown in Chapter 5 for the eleven elements investigated in this project and across the fourteen Globular Clusters. The analysis of the chemical trends and multiple populations from the determined abundances is in Chapter 6. Chapter 7 discusses the findings and wider implications of this project to the chemical understanding of the Milky Way. Finally, Chapter 8 concludes the work done in this thesis and provides an overview of any possible future work.
  • ItemOpen Access
    An automated approach to mapping variability of hāpua morphodynamics in Aotearoa.
    (2025) Baker, Alaina
    Hāpua are freshwater river mouths that are parallel to the coastline with a dynamic gravel or mixed sand and gravel barrier intermittently separating them from the marine environment. Our understanding of hāpua processes are limited by a lack of high frequency and high quality data. To address this lack of data, deep learning models are tested across hāpua located along the Canterbury Bight. The resulting models produce 2-dimensional masks of wet/dry areas. Delineations of water and land provide insight into hāpua morphology and water storage changes. Field work at these lagoons can be challenging, which means hāpua studies tend to focus on individual sites. There are few studies that report synoptic information on the morphology of multiple hāpua and interrogate their changing form. To address this data gap, this thesis presents water mask results using a deep learning framework to delineate hāpua using high-resolution and near daily frequency imagery from the Planet satellite constellation. In this approach a convolution neural network is built and trained to automate the delineation of binary (wet/dry) masks to represent lagoon, barrier and tidally influenced river areas a system wide scale. These masks are used to conduct a long term study of the Rangitata hāpua morphology. The results highlight that the convolution neural network model trained with 90 scenes at a tile mosaic of 10 by 10 pixels (T90M10) produced the most reliable water masks both through time and across study sites. A comparison between manual shore line delineation, a semi-automatic classification tool, and the T90M10 model demonstrated a close fit. However, the CNN model demonstrated slight under fitting of the water line and is therefore conservative in its water estimates. This thesis also undertook an analysis of hāpua morphology over time. Through water masks from the T90M10 model, it was found that mouth width and orientation fluctuate in response to river flow, where wider openings correlating with straight mouth positions. Mouth width also correlates inversely to hāpua water volume, whereby wide mouth openings result in lower observed volumes. With increasing pressures of water abstraction coupled with changing river regimes and sea-level rise under a changing climate, this approach offers important insights that may help to benchmark current conditions.
  • ItemOpen Access
    Online gaming as a coping mechanism for social anxiety : qualitative analysis of r/socialanxiety
    (2025) Dimant, Tal
    This study explores the intersection of social anxiety and online gaming, focusing on how individuals with social anxiety navigate these virtual environments to manage and mitigate their symptoms. Utilising qualitative data scraped from the subreddit r/socialanxiety, the research identified three primary themes: 'Coping Strategy,' 'Virtual Safe Spaces,' and 'Social Interaction,' each encompassing multiple subthemes such as 'Escapism,' 'Alter Ego Exploration,' and 'Parasocial Connection.' Findings highlighted both the benefits and risks of online gaming, offering therapeutic benefits like stress relief, self-confidence building, and structured social engagement, while also presenting risks related to avoidance behaviours and dependency. The study draws connections to existing literature on gaming, anxiety, and virtual environments, emphasising the unique affordances of these platforms for socially anxious individuals. Implications for therapeutic interventions and future research directions are discussed, including how findings can be leveraged to enhance the positive aspects of gaming while mitigating its potential drawbacks. This work contributes to the growing body of knowledge on the psychological impact of digital environments, particularly for vulnerable populations.
  • ItemOpen Access
    Client experiences of non-mandated harmful sexual behaviour services in Aotearoa New Zealand : a qualitative analysis.
    (2025) Ruddle, Simone A.
    Sexual violence is a significant issue in Aotearoa New Zealand, with high rates of victimization and substantial costs to individuals, whanau and communities alike. While specialist services exist for harmful sexual behaviours (HSB), non-mandated clients—those engaging voluntarily—face a myriad of barriers to accessing treatment. This study explores the experiences of non-mandated HSB clients across three community-based providers in Aotearoa New Zealand, identifying factors that support engagement in therapeutic services, while enhancing well-being and preventing relapse. Using a qualitative approach, semi-structured interviews with 14 participants from all over New Zealand were analysed using Braun and Clarke’s reflexive thematic analysis. Six key themes were elicited from the data: (1) externally motivated engagement in services, (2) perceived barriers to treatment initiation, (3) quality therapeutic alliance, (4) responsivity considerations, (5) holistic support, and (6) therapeutic gains. Findings highlight external motivators, such as encouragement from authority figures or family, while barriers included fear of the unknown and long wait times. A strong therapeutic alliance, individualized approaches, and holistic support were critical in sustaining engagement. Participants reported cognitive-behavioural strategies, psychoeducation, and the importance of vulnerability as pivotal to their ongoing personal development and enhancing their wellbeing, reducing the chances of future harmful behaviour. This study aligns with existing research while revealing unique insights into engagement mechanisms in non-mandated interventions. Findings emphasise the importance reducing stigma, improving access to specialised services, and fostering client-centred approaches for effective intervention. Future research should explore long-term outcomes and strategies to encourage early intervention.
  • ItemOpen Access
    Extreme precipitation events in Aotearoa New Zealand : regional characteristics and links to atmospheric blocking,
    (2024) Vishwanathan, Gokul
    Extreme precipitation events (EPEs) pose significant risks globally, often resulting in severe flooding, infrastructure damage, and widespread societal disruptions. These events are particularly impactful in Aotearoa New Zealand (ANZ), a region where complex topography and frequent exposure to moisture-rich atmospheric systems exacerbate their effects. With climate change expected to intensify the frequency and severity of EPEs, understanding their behavior and underlying causes is increasingly vital. This thesis investigates EPEs in ANZ, focusing on their characteristics across various Regional Council regions and the synopticscale processes, such as atmospheric blocking, that modulate the properties of these events. We first undertook a detailed evaluation of precipitation datasets for ANZ due to limited clarity on which datasets best capture both mean and extreme precipitation features. The motivation was to identify a suitable dataset that could serve as a reference reliably capturing both mean and extreme precipitation patterns across ANZ for use in further analyses. We conducted a comprehensive evaluation of precipitation datasets, examining station data, satellite-gauge merged products, reanalyses, and in-situ gridded products over a ten-year period (2001–2010). Mean precipitation patterns showed general consistency across all products, with clear maxima over mountainous regions; however, only higherresolution datasets accurately represented the west-east precipitation gradient across the South Island. For extreme precipitation, a set of climate indices was used to examine the distribution’s upper tail, revealing significant discrepancies between products, especially over the West Coast of the South Island, highlighting substantial uncertainty in gridded precipitation extremes. MSWEP, BARRA-R, and ERA5 emerged as top-performing gridded datasets across various statistical tests, including higher non-parametric Kling Gupta Efficiency (NP-KGE) scores, underscoring their capacity to capture both mean and extreme precipitation across ANZ. Consequently, based on the statistical assessments conducted, MSWEP was chosen as the reference for accurately representing mean and extreme rainfall in this thesis, while ERA5 was chosen to investigate the characteristics of EPEs given its broader range of variables, global coverage, and extended time frame. Going forward, these datasets will serve as the foundation for analyzing rainfall patterns and understanding EPE dynamics across ANZ. Next, we analyze the characteristics of EPEs across ANZ’s Regional Council regions using the recently curated Extreme Weather Events (EWE) database. This analysis focuses on three key attributes: total rainfall accumulation, event duration, and peak intensity, evaluated through a novel spatiotemporal framework applied to ERA5 and MERRA-2 datasets. Two primary types of EPEs were identified from the EWE database: “R” events, associated with large-scale synoptic systems, and “C” events, driven by localized convective systems like thunderstorms. Although event classification was subjective, our results reveal clear physical distinctions between these event types in both datasets. In particular, we found that EPE duration consistently had a stronger influence on total precipitation accumulation than peak intensity across all regions and event types, highlighting the critical role of sustained precipitation in shaping ANZ’s extreme rainfall patterns. Given this strong link between event duration and rainfall accumulation, we next investigated the mechanisms contributing to extended EPE durations. We hypothesized that atmospheric blocks may play a role in prolonging EPEs, given their well-documented ability to keep rain-producing systems stationary. To test this, we aggregated EPEs across all Regional Council regions in ANZ, creating a composite view to analyze how blocking systems might influence event durations. Results showed that atmospheric blocking frequency is significantly higher during EPE days than climatology, supporting the hypothesis that blocks are more prevalent during extreme events in ANZ. This increased frequency revealed two primary blocking locations: one in the Southern Ocean, south of ANZ, and another in the South Pacific Ocean to the east. We believe these two locations represent optimal positions for atmospheric blocks to effectively stall rain-bearing systems, with the southern blocking likely associated with northerly-driven EPEs and the eastern region linked to westerlydriven EPEs. This configuration underscores the critical role of these blocking positions in sustaining EPEs by preventing the movement of rainfall systems over ANZ. Furthermore, a clear relationship emerged between block proximity and EPE duration. Blocks were consistently closer to regions experiencing the highest-duration (HD) EPEs than the lowest-duration (LD) events, offering statistical support that blocks proximity directly influences rainfall duration. For HD events, larger block areas often coincided with closer block distances, suggesting that both block size and location may be instrumental in prolonging EPEs. In contrast, LD events showed little relationship between block area and proximity, indicating that other factors, such as regional atmospheric dynamics and geographical features, may also shape EPE characteristics across ANZ. These findings highlight the critical role of atmospheric blocking in modulating the duration of EPEs and underscore the complexity of interactions that sustain extreme rainfall over time. Finally, we examined how the location of blocking patterns changes depending on the direction of moisture flow associated with EPEs across different regions in ANZ. To achieve this, we categorized EPEs by their background flow direction, using 850 hPa wind and Integrated water vapor transport(IVT) fields measured at representative points in each region. The analysis revealed that EPEs in various regions of ANZ predominantly originated from specific preferred directions. Overall, these patterns remained consistent when using both the 850 hPa wind and IVT fields, with only minor differences in their absolute numbers. Composite maps of synoptic setups revealed distinct blocking positions that align with EPE flow directions, highlighting the role of the low-pressure flank of composite omega blocks, which guides moisture into affected regions, especially during easterly-driven events. Higher averaged blocking fractions were observed opposite the direction of rainfall-bearing systems in Northland, Gisborne, and Canterbury, emphasizing the role of atmospheric blocks in obstructing the propagation of these systems and sustaining precipitation. However, blocking had minimal impact on the West Coast, where EPEs are primarily orographically driven, underscoring the dominance of orographic uplift in this area. A case study of the 16–17 July 2004 EPE affecting Bay of Plenty and Gisborne validated the composite findings, illustrating the influence of a blocking high east of ANZ in stalling the rain-bearing system and extending rainfall duration. These findings emphasize the spatial and directional variability of atmospheric blocking and its impact on moisture transport pathways, further refining our understanding of the mechanisms driving prolonged EPEs across ANZ.
  • ItemOpen Access
    Assessing key drivers of cyanobacterial blooms in urban stormwater ponds: a case study in Ōtautahi | Christchurch.
    (2025) Koviessen, Stephanie C.
    As urbanisation increases and flooding events become more frequent and severe, it likely that the number of stormwater ponds will increase, and they will become more eutrophic. Stormwater ponds are often nutrient-rich environments ideal for cyanobacteria. Some cyanobacteria are known to produce cyanotoxins which have been associated with numerous dog deaths in Aotearoa|New Zealand. Concerns over cyanobacterial blooms and toxic production in stormwater ponds has led to increased interest to identify the underlying cause. Previous studies have inferred that environmental drivers for cyanobacterial blooms in stormwater ponds are similar to those identified for lakes and other eutrophic environments, but there is a limited understanding of the influence of stormwater pond design and physicochemical factors on cyanobacterial communities. To address this knowledge gap, I undertook two studies to investigate cyanobacterial community composition in stormwater and urban ponds to determine how design attributes and physicochemical factors influence cyanobacterial dynamics. The first study involved analysing temporal patterns in physicochemical variables and the abundance of cyanobacteria using conventional microscopic techniques. This revealed that cyanobacteria were present in stormwater ponds with evidence of cyanobacterial blooms in some, but not all, ponds. In general the cyanobacterial biovolumes were low. Linear mixed models identified physicochemical variables associated with total algal biomass, with total phosphorus being the most important explanatory variable. I identified linkages between hydraulic residence times, nutrients, and cyanobacterial biovolumes where stormwater ponds with high flush rates had lower total phosphorus and cyanobacterial biovolumes. The second study involved a broad spatial survey of cyanobacterial communities in stormwater and urban ponds using a molecular technique known as metabarcoding. This revealed that cyanobacteria are prevalent and that communities differ across trophic gradients. Picocyanobacteria were identified as a dominant taxon. Known bloom forming species Aphanizomenon and Planktothrix dominated hypertrophic environments. Nutrients, temperature, and conductivity were all correlated with different cyanobacterial taxa, confirming their importance in bloom development. Surface area showed a general positive association with Aphanizomenon. However, this trend was not universal, as the species was absent in some larger ponds, indicating that factors beyond pond size, such as environmental conditions or ecological interactions, may influence its presence and abundance. Lastly, by using molecular techniques, I confirmed the absence of microcystin (a hepatoxic cyanotoxin) producing genes, confirming that this cyanotoxin was not present in these ponds at the time of sampling. My research highlights the importance of understanding how stormwater pond design and environmental factors interact to influence cyanobacterial dynamics, offering insights to inform strategies for mitigating cyanobacterial blooms and associated risks. Future studies could explore how climate-driven changes, such as altered rainfall patterns and warming temperatures, might further influence cyanobacterial community composition and bloom dynamics in stormwater ponds, providing critical information for adaptive management.
  • ItemOpen Access
    Modelling neutrino emission near supernova remnants.
    (2025) Eldridge, Christopher
    The question of the origin of cosmic rays has long been a topic of central importance in astroparticle physics. Spectral features suggest the existence of sources in our Galaxy capable of accelerating cosmic rays to PeV energies; these have yet to be definitively identified. Supernova remnants (SNRs) contain shock fronts with the necessary size and magnetic field to accelerate particles to ultrarelativistic energies through diffusive shock acceleration and are generally considered to be the main contributors to the cosmic ray flux in the “knee” area. In the presence of an interstellar cloud (or other relatively dense object) near an SNR, interactions between cosmic rays and matter within the cloud produce gamma rays and neutrinos which, unlike the cosmic rays themselves, are electrically neutral. SNR-cloud pairs should thus produce a detectable neutrino excess at a well-defined point in the sky. We present a pipeline which models SNR–molecular cloud pairs and predicts the neutrino flux from cosmic-ray interactions within the cloud. It determines the energy spectrum and release times of protons accelerated in the SNR, then models their diffusion through the interstellar medium to find the flux incident on the molecular cloud. It then calculates the spectrum of neutrinos produced by interactions of the incident cosmic rays with hydrogen in the cloud. Finally, this is converted into the neutrino spectrum as observed from Earth. We find that many of the regions predicted to contain the brightest sources correlate with previously-identified regions of gamma emission, suggesting that the pipeline is effective in identifying potentially significant SNR–cloud combinations. These results may be used as the basis for an IceCube source search in future, although further investigation of significant candidates is needed.
  • ItemOpen Access
    Conversation to support growth : exploring the application of motivational interviewing within sport coaching.
    (2025) Orritt, James Thomas
    This thesis explores the application of Motivational Interviewing (MI) within the context of sports coaching, examining its influence on coach-athlete communication and athlete motivation. The study addresses the need for effective communication strategies in sports coaching, which is a distinctive discipline requiring a blend of science and art. The research uses a mixed-methods design, employing both qualitative and quantitative data to investigate the perceived and experiences of MI training for coaches, along with the impact of MI training and an ongoing learning community on coaching practices and athlete engagement within conversations. The research includes two studies: Study 1 involved focus groups with ten coaches (n=10), from diverse sporting backgrounds, to explore their perceptions of integrating MI within their coaching. The coaches identified several challenges to implementing MI, including time constraints, cultural norms, competitive pressures, and the variable engagement and readiness of athletes for change. Coaches identified barriers to consistent MI application, including challenges in fostering behaviour change, especially with younger athletes. They also saw opportunities for MI to improve coach-athlete relationships, raise coaching awareness, and boost athlete motivation and self-reflection. Phase 1 of Study 2 explored coaches' experiences with MI training and its impact on their coaching practices. Interviews were conducted with five of the nine coaches who participated exclusively in the training days. Several key themes emerged regarding their experience of the MI training. Coaches perceived that the MI training addressed gaps in their coaching practices, providing them with new practical skills that they felt were not strongly emphasised in previous coach development programs.. They also noted that the training enhanced their self-awareness, prompting them to reflect on their coaching goals and values. However, they also acknowledged the difficulties in applying the theoretical concepts and integrating new skills into their long-established routines. Coaches expressed a need for ongoing support and further training to master the practical application of MI, with the suggestion of a learning community and continued coaching to support their learning. They also felt sport-specific examples were needed to better facilitate learning into the sport environment. Phase 2 of Study 2 examined MI implementation by two coaches, with ongoing feedback over 14 weeks delivered via the learning community and individual phone calls. Coach A recorded sessions pre-training (n = 3) and post-training (n = 6), while Coach B recorded only post-training (n = 5). The learning community was generally perceived as a positive experience, with coaches noting that individualised feedback helped them deepen their MI skills. They also described growth in their reflective practice, particularly through the process of re-listening to past coaching conversations—something they had not done before. In Phase 2 of Study 2, one athlete per coach was interviewed, both reporting increased autonomy and empowerment during their involvement in the conversations. Quantitative assessments of the audio recordings using the MITI4.2.1 and CLEAR scales indicated some improvements in MI skill, particularly in cultivating change talk and using reflections. However, these gains were not consistent across all coaches, and variability remained. Athletes speaking time relative to coach speaking talking also increased. In summary, this research highlights the potential benefits of applying MI in sports coaching, in supporting the coach-athlete relationships, increasing coach self-awareness, and growing athlete motivation. However, challenges for integrating MI within the sport context were also identified, such as the need for ongoing support to learn and implement MI, the need for more sport-specific training examples, and the challenge of integrating it within a outcome focused culture. Nonetheless, his study was the first to analyse real-world coaching conversations while incorporating athletes’ perspectives, providing preliminary support for the integration of MI in sport coaching. However, the small sample size and limited baseline data restrict the findings, highlighting the need for larger, longitudinal studies across diverse sporting contexts.
  • ItemOpen Access
    Detection sensitivity and specificity of a mismatch response protocol.
    (2025) Towers, Leith Sye
    Background: Validation procedures following the fitting of hearing devices are crucial for accurately assessing the effectiveness of those fittings and to ensure they meet the auditory needs of users. Traditional methods include subjective reporting and behavioural assessments of speech intelligibility. These methods have limitations in terms of consistency, reliability, and applicability, particularly when working with young children, individuals with cognitive impairments, or those unable to provide accurate feedback. The methods often fail to offer objective, quantifiable data on the ability to discriminate sounds heard via the hearing device in these populations, which is essential for effective hearing device validation. Recent investigations into the Mismatch Response (MMR) have shown promise in providing an objective biomarker for auditory discrimination. MMRs are an electrophysiological measure that can index neural responses to changes in sound, which can offer speech intelligibility information without behavioural feedback. However, the process of transitioning MMR-based testing protocols from the research setting towards a clinic-ready tool for hearing device validation remains an area of active exploration. A key challenge for the clinical setting is analysing and interpreting MMR data at the level of the individual listener. This study aims to evaluate the detection sensitivity and specificity of a protocol used for eliciting MMRs and analysing the ensuing data via Hotelling’s T² - a statistical analysis technique that can be used for determining electrophysiological response presence or absence in individuals. Design: Electrophysiological data from three cohorts of listeners informed the present study. MMR detection sensitivity was estimated from data involving 16 normally hearing infants (3-13 months) and 17 normally hearing adults receiving stimuli to trigger an MMR, while no-sound trial data from 76 normally hearing adults was used to estimate detection specificity. Results: The Hotelling’s T² detection algorithm demonstrated acceptable specificity, with false detection rates of 6.6%, which decreased to 4% after applying upper-confidence interval exclusionary criteria with 10,000 bootstrap samples. Combined with detection sensitivity of 93% from the MMR data, performance of detection algorithm overall was observed to be high. Conclusion: This study demonstrates that MMR testing, with high specificity among adults, shows promise as a reliable tool for early hearing device validation. While further refinement and research is needed, MMR testing holds strong potential for clinical use.
  • ItemOpen Access
    Workload, recovery experiences, and job satisfaction : exploring the role of cultural dispositions in recovery.
    (2025) Mukherjee, Spandan
    Workload is a critical factor influencing employees' recovery experiences, which in turn impact well-being and job satisfaction. This study examines the relationships between quantitative workload and four key recovery experiences: psychological detachment, mastery experiences, relaxation, and control over leisure time. Additionally, the moderating roles of cultural dispositions, including individualism-collectivism, power distance orientation, and masculinity-femininity, were explored. A cross-sectional design was employed, with data collected via an online survey. Participants (N = 152) were recruited using convenience sampling through social media platforms such as LinkedIn and Facebook. The study spanned six weeks, with three rounds of recruitment. The hypotheses proposed that high quantitative workload would be negatively associated with psychological detachment (H1a), mastery experiences (H1b), relaxation (H1c), and control (H1d). The results largely supported these hypotheses, with quantitative workload significantly predicting lower psychological detachment, relaxation, and control. However, no significant relationship was found between workload and mastery experiences. The study further hypothesized that cultural dispositions would moderate these relationships. Contrary to expectations, power distance orientation and masculinity-femininity did not significantly moderate any associations. However, individualism-collectivism moderated the relationship between workload and mastery experiences (H4b), indicating that individuals with collectivist orientations experienced a stronger negative effect of workload on mastery compared to those with individualist orientations. These findings contribute to the literature on workload and recovery by highlighting the influence of cultural dispositions. The results suggest that organizations should consider employees’ cultural backgrounds when designing workplace interventions aimed at improving recovery experiences. Future research should further investigate the mechanisms through which cultural values shape recovery processes in diverse work environments.
  • ItemOpen Access
    When there is no water cooler : how employee resilience can be developed and enacted in remote work.
    (2025) Nelson, Sophie
    Remote work presents several unique challenges for employees. Employee resilience may be an important capability in overcoming these challenges, denoting the ability to develop and draw on resources to adapt to changes and challenges at work. While resilience has been widely studied in co-located workplaces, less is known about how resource development and utilisation behaviours to overcome the unique challenges associated with remote work can be supported. This study aimed to qualitatively explore how remote workers develop and enact resilience and the factors that promote or undermine resilience development in this context. Fifteen workers who have worked remotely for at least twelve months were interviewed about how they approach challenges at work, the strategies they develop to overcome these challenges, and the role of organisations and leaders in supporting employees in remote work. Thematic analysis identified three broad themes. Two themes reflect resilient behaviours in remote work: ‘utilising social resources and managing social demands’ and ‘managing self’, while the third theme ‘organisational enablers and barriers to resilience’ reflects the ways in which organisations and managers can support or hinder these behaviours. Key resilient behaviours derived from the data and themes include network development, seeking and leveraging support at work, boundary-setting behaviours, learning, managing personal resources, and adaptive task management. Resilience-promoting factors included a supportive work environment, facilitating communication and learning, and support from leaders. The findings suggest that organisations should invest in the technology infrastructure required to support social connection, train leaders to foster a resilience-enabling environment, provide guidelines and design jobs to consider boundaries between work and home and equip remote workers to manage emotional demands to promote resilience development.
  • ItemOpen Access
    Of mice and women : variation of the stress response and stress-mediated maternal effects in the House mouse (Mus musculus)
    (2024) Manton, Deborah
    The influence of maternal stress on offspring development can have significant consequences for offspring responses to stress. While stress can impact postnatal maternal care, stress during gestation can be transmitted to offspring via maternal effects; where maternal phenotype influences offspring phenotypes. Many studies have demonstrated maladaptive maternal effects, but prenatal stress exposure may provide adaptive benefits to offspring. Here I test the effects of reduced maternal stress on the offspring stress response in the House mouse (Mus musculus). Reduced prenatal stress results in daughters with a less reactive stress response, who receive increased maternal investment, while sons remain unaffected. Additionally, I examine the influence of different environments, and different maternal environments, on the stress response of mice. Results demonstrate stress responses are influenced by environment, and maternal environment, in a similar and sex-specific manner. I discuss the adaptive significance of stress-mediated maternal effects and the implications of these findings for animals and humans.
  • ItemOpen Access
    The influence of rodent anterior thalamic - prefrontal cortex - dorsal subiculum circuitry in spatial working memory and immediate early gene expression.
    (2024) Ram, Xavier
    The anterior thalamic nuclei (ATN) are a crucial processing hub for memory and neural network integration. We explored the influence of the ATN in combination with state-of-the-art temporary optogenetic inhibition of its projections to medial prefrontal cortex (mPFC) and dorsal subiculum (dSUB) in spatial memory using the Win-Shift Eight-Arm Radial Arm Maze (RAM). We also assessed c-fos, an immediate early gene, expression changes in anterior cingulate (ACC) and rhinal cortices in these interconnected regions. We used 28 PVG hooded rats in four groups: bilateral ATN lesions (ATN Bilat), unilateral viral vector infusion to inhibit cortical axon terminals and ATN lesion (VV+ATN), unilateral viral vector infusion and Sham lesion (VV+Sham), and a control non-opsin viral vector infusion and ATN lesion (VVneg+ATN). We found that only rats in the ATN Bilat group made significantly more errors in the RAM, while the other three groups were all unimpaired. Interestingly, the ATN Bilat group with no viral vector infusion showed increased errors during optogenetic stimulation, potentially indicating hypersensitivity to the optic-fibre light shining. Ex vivo, c-fos expression was significantly increased in the viral vector infused hemisphere of ACC for VV+Sham and VVneg+ATN groups - a puzzling finding given the VVneg+ATN group received the no-opsin (control) infusion. However, c-fos expression was similar between ACC hemispheres for VV+ATN rats, aligning with prior studies. While unexpected, these findings demonstrate the ATN is crucial for spatial memory and suggest light may influence ATN retinal inputs, which warrants further investigation.