Science: Theses and Dissertations

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  • ItemOpen Access
    Hydrogeology of the Eastern Southland Plains, New Zealand
    (2001) Durie, Michelle Anne
    The Eastern Southland Plains is situated between the Oreti and Mataura Rivers, and the area of approximately 45 km2 under investigation in this study includes the Morton Mains, Waimatua, and Kapuka coalfields. Farming is the principal land use in the region, particularly dairying, and groundwater resources are utilised widely. This thesis provides a detailed investigation of the Early Quaternary and Gore Lignite Measures aquifer systems by delineating the hydrogeological setting, groundwater trends and fluctuations, groundwater yields and water chemistry issues with specific reference to potability.
  • ItemOpen Access
    Sediment and soil erosion and possible remediation scenarios in Governors Bay, New Zealand.
    (2023) Evans, Joshua David
    High rates of sedimentation in Governors Bay, Whakaraupō, New Zealand have led to the expansion of mesotidal mudflat and shallowing of the bay. This has been identified as a significant issue for local mana whenua, recreational activities, and fishing in the bay. Previous research has identified that this sediment is most likely drawn from the catchment immediately surrounding Governors Bay. This study aims to identify the source of the sediment in Governors Bay, better constrain its location within Governors Bay, and provide solutions in the form of possible remediation scenarios to enact to reduce erosion rates across the catchment. This was achieved through the acquisition and analysis of an 84 cm sediment core in Governors Bay as well as 36 sediment samples from the catchment to determine sediment provenance. This information was combined with InVEST sediment delivery ratio modelling software to identify areas of greatest concern in terms of sediment erosion as well as the land use types which contribute the most to sediment erosion and the types which can best be used to prevent it. Geochemical, total organic carbon and grainsize analysis of the sediment core and samples from the catchment identify the primary sediment source entering the bay as being that found below the 200 m contour in the catchment. This area corresponds to loess and loess colluvium stratigraphy and loess derived soils. Modelling of sediment erosion in the catchment suggests that the highest rates of erosion are found on hill slopes with grassland cover and in areas of urban development. Areas with the lowest rates of sediment erosion are found to be those with relatively flat topography and native forest cover. A remediation scenario is proposed to restore native forest to Governors Bay. The initial focus is suggested to be areas of grassland below the 200 m contour, with simultaneous removal of pests and weeds that would threaten native forest growth. Focus can then shift to reforesting the entire catchment in native forest over the long term apart from urban development. This scenario provides an effective option to reduce overall sediment erosion rates in the catchment, slow the expansion of the mesotidal mudflat to near natural growth levels, and to restore and prolong the cultural health of Governors Bay as well as securing future accessibility to the waters of the bay for the local community.
  • ItemOpen Access
    Countering violent extremism online : the impacts of cognitive restructuring on violence endorsement.
    (2023) Taufahema, Renaye Claire
    Violent extremism has been a longstanding threat to peaceful relations in democratic and pluralistic societies. The growing presence of online extremism provides extremists access to more people and a sense of anonymity. Online interventions for violent extremism provides potential scalability whilst removing the need to identify and locate these individuals in order to deliver the interventions therefore providing greater reach to vulnerable individuals. As such, the current study aimed to explore whether cognitive restructuring implemented online could reduce ideologically-motivated violence endorsement. It was hypothesised that the online cognitive restructuring intervention would reduce levels of violence endorsement and based on the Cognitive-Experiential Self-Theory (Epstein, 1985), it was further hypothesised that perceived unfairness would be the mechanism through which cognitive restructuring had an effect. As violence endorsement has been associated with self-uncertainty, conviction, inflexible thinking, opposition to individual liberty, and greater identity fusion, these were considered potential moderators of the effects between cognitive restructuring and violence endorsement. A total of 270 US participants were recruited based on their responses to a large screening survey (N = 1,691) conducted on Prolific. Participants were presented with an ideological statement and completed either the cognitive restructuring or control task. The cognitive restructuring condition encouraged participants to consider alternative viewpoints and evidence which does and does not support their view. Data revealed that online cognitive restructuring did not reduce violence endorsement related to ideological statements. However, exploratory analyses found that cognitive restructuring did reduce violence endorsement specifically among people who perceived greater unfairness related to the ideology, had higher intellectual humility, or were in opposition of individual liberty. Together, results suggest that online cognitive restructuring may be beneficial in reducing ideologically motivated violence endorsement, although potentially only for certain kinds of extremists.
  • ItemOpen Access
    The perceptions and understandings of wellbeing during early adolescence : the perspectives of adolescents, whānau and teachers in Aotearoa New Zealand.
    (2023) Key, Samantha
    Wellbeing is crucial for learning and student success, and interest in wellbeing research has rapidly grown over recent decades as mental health research has shifted towards a focus that seeks to boost positive aspects of mental health, including the promotion of wellbeing (Keyes, 2007; Noble & Wyatt, 2008). Wellbeing has been linked to a wide range of indicators of emotional health, mental health and social functioning and successfully navigating childhood challenges and is critical to developing healthy patterns for adulthood (Proctor et al., 2009). Global trends show declining levels and the earlier onset of emotional and behavioural difficulties in childhood, with risk factors often compounding during adolescence (Brauner & Stephens, 2006; McCollom et al., 2008; UNICEF, 2017). UNICEF (2020) recently reported that New Zealand dropped to 35th out of 41 OECD countries for child wellbeing outcomes. Youth2000 data from 2000 to 2012 highlighted the poor levels of wellbeing New Zealand’s youth are experiencing (Fleming et al., 2014). The cumulative effect of wellbeing needs not being met in earlier years is adversely affecting the outcomes of students in years 7 and 8, as evidenced by rates of students not achieving at or above National Standards, as well as suspension and stand-down rates, which surpass those found in students in years 1 to 6 (Education Review Office, 2015). The concept of wellbeing is evident in New Zealand’s education pathway through the principles and strands of Te Whariki, the early childhood curriculum and the values and key competencies of The New Zealand Curriculum (NZC) for schools (Ministry of Education, 2017). Most definitions posit wellbeing within physical, psychological, social and emotional wellbeing (Manning & Fleming, 2019). Social and emotional wellbeing (SEW) is a significant component of wellbeing. It has recently been prioritised within New Zealand through a series of Government and Educational Strategies (Department of the Prime Minister and Cabinet, 2023). SEW refers to how people think and feel about themselves and others (Australian Institute of Health and Welfare, 2012). The conception and development of SEW stem from an individual’s perceptions, culture, language and spirituality (Pitama et al., 2002; Smith et al., 2019). SEW has been linked with increased academic outcomes and improved attitudes, behaviour, and student engagement (Corcoran et al., 2018; Durlak et al., 2011; Taylor et al., 2017). Schooling is a vital environment for the promotion of wellbeing. Social-emotional learning (SEL) has been identified as an effective tool within education which develops selfesteem, self-confidence, academic achievement, attitudes, behaviour and engagement in learning which are considered essential to wellbeing (Corcoran et al., 2018). Fostering and supporting the maintenance of SEL skills in ākonga has led to reduced difficulties in behaviours and emotions (Taylor et al., 2017). Wellbeing is necessary for successful engagement of ākonga throughout their school years and lifespan and low wellbeing in early years adversely influences outcomes for students in years 7 and 8. However, little is known about what early adolescents perceive wellbeing to be for themselves. This study contributes to wellbeing research by focusing on early adolescents’ perceptions regarding what they believe and experience to be wellbeing. The study also engages with their whānau and teachers to understand what they perceive fosters and maintains wellbeing in ākonga at home and school. The current study uses a grounded theory methodology to provide insight and understanding into the participants lived experiences and the influence of context and culture on their perceptions of wellbeing. Data was collected through a series of wānanga over four months in 2022 at an intermediate school in urban Christchurch. The main findings of the study identified a number of themes that fostered or detracted from ākonga wellbeing. Interpersonal relationships were recognised within the data as being vital to ākonga perceptions of wellbeing with relationships with friends and whānau of most significance. It was clear that difficulties in the lives of ākonga had an adverse impact on their wellbeing perceptions and these perceptions were recognised as being vital to their emotions and cognitions and thus, influenced their SEW and SEL. Whānau and teachers supported this as they too recognised that how ākonga perceived themselves and others impacted their wellbeing both at home and in the classroom.
  • ItemOpen Access
    Evaluation of the assessment of dissociative symptoms in a public mental health service setting.
    (2023) McKie, James
    Dissociative symptoms occur commonly in general population, inpatient and outpatient samples. However, due to its subjective nature, dissociation may be hard to be observe or assess. If dissociation remains undetected, it is possible that treatment will not be as effective in reducing psychological distress. Little is known about the detection of dissociative symptoms in Aotearoa New Zealand, except that 0.001% of mental health service users with a diagnosis have a primary dissociative disorder diagnosis (Ministry of Health, 2023). Twenty-six specialist mental health service users (mean age = 39.88; SD = 12.70; M = 9, F = 17) from Te Whatu Ora Waitaha (Health New Zealand Canterbury) completed the 60-item Multidimensional Inventory of Dissociation (MID-60), and consented to having their psychiatric reports, completed after a psychiatric assessment, scored for mentions of dissociative symptoms. The overall MID-60 mean (M = 30.25) indicated the sample as a whole experienced dissociative symptoms with a level consistent with a dissociative disorder and/or PTSD. All but one participant exceeded at least one clinical cut-off of the MID-60 subscales. The MID-60 significantly detected more dissociation than the psychiatric reports, specifically on Angry Intrusions, Depersonalisation/Derealisation, Distress about Severe Memory Problems, Loss of Autobiographical Memory, Flashbacks, Body Symptoms, Psychogenic Nonepileptic Seizures, Trance and Self-Confusion. These findings suggest dissociation may be going undetected in psychiatric assessments. It is recommended that every specialist mental health service user is screened for dissociation at their initial psychiatric assessment to ensure detection.
  • ItemOpen Access
    Notes from the backyard : representations of Antarctica in narratives from Argentina and Chile (1886-2023).
    (2023) Wainschenker, Pablo
    The stereotypical representation of Antarctica in Argentina is set around Marambio Station, a logistical hub located on the northeast side of the Antarctic Peninsula and managed by Argentina’s Air Force, where people (mostly members of the military) stay year-round. It might be thought that in popular imagination about Antarctica, there is little else. Antarctica seems to be a distant part of the country guarded by a small group of government officers. This thesis shows that, alongside a nationalist narrative that revolves around sovereignty claims and heroic efforts, since the late nineteenth century there has been in Argentina and Chile a body of narratives focused on a range of other issues. These narratives challenge the idea that there is only one, homogeneous way of literary engagement with the icy continent from the Southern Cone, and evidence that Antarctic narratives are an arena of symbolic disputes. In addition, the thesis looks at the relationship between a dominant Anglophone representation of Antarctica and narratives produced in Argentina and Chile. Although Anglophone Antarctic imagination has been thoroughly studied, large areas of South American Antarctic imagination remain unknown, and so are the points of intersection between South American Antarctic narratives and English Antarctic culture and fiction. The thesis examines these linkages, including the assumption, in Anglophone imagination, of a spatial and symbolic disconnection between the white continent and the rest of the world. Previous research focused on Argentine Antarctic fiction has studied a body of literary works strongly aligned with a nationalist perspective. These narratives provide a homogeneous picture in which Antarctica (or, strictly speaking, the fractions of the continent claimed by Argentina and Chile) is seen as a distant part of the national territory that must be guarded by brave men. This thesis expands that research by: presenting a new body of Antarctic narratives written in Argentina and Chile; examining non-nationalistic types of literary engagements with the icy continent; and investigating how Anglophone Antarctic imagination intersects with narratives from South America’s Southern Cone. Structurally, the thesis is arranged according to three main themes: Space and Place, Actors and Travels, and the materials are organised in three periods. The thesis is centred around two primary research questions. The first asks, ‘How do Southern Cone narratives represent Antarctica?’ Literary analysis is used to answer this question, on a corpus composed of short stories, novels, graphic novels and travel narratives from Argentina and Chile published between the end of the nineteenth century and the present. The second research question asks, ‘How do Southern Cone Antarctic narratives differ from (or reinforce) dominant Anglophone narratives?’ The thesis reveals that Anglophone culture and history permeate Southern Cone Antarctic narratives, even while these texts construct an idea of Antarctica from a South American perspective, different from the Anglophone one. In answering these questions, this thesis provides a detailed account of key features of the Southern Cone’s Antarctic imagination as it surfaces narratives, and highlights differences and commonalities with Anglophone imagination. In doing so, this thesis contributes to a better understanding between the Southern Cone countries and Anglophone culture. This issue is of key importance, not least given the uncommon political status of Antarctica, where a culturally diverse group of countries govern by consent.
  • ItemOpen Access
    The Role of Understudied Personal and Job Resources for Wellbeing Among Knowledge-Based Professionals
    (2024) Grant, Renske
    Organisations have had to address unique challenges their employees faced amidst the COVID- 19 pandemic. Concurrently, work-related factors such as constantly changing work environments, advancements in technology, and job insecurity, can potentially undermine employee work-related wellbeing. However, addressing these negative factors can result in enhanced employee wellbeing, improved performance, decreased absenteeism, and stronger coworker relationships, ultimately contributing to organisational success. Therefore, exploring how personal and job resources can positively impact employee wellbeing becomes imperative. The roles of psychological safety, emotional intelligence, emotional regulation, and help-seeking are understudied in the context of wellbeing. Addressing this gap, the current thesis explores the impact of these less-researched job and personal resources on wellbeing outcomes of knowledge-based workers. Two multi-phase quantitative studies were conducted: Study 1 evaluated a wellbeing intervention for junior lawyers recruited from the New Zealand Law Society. Study 2 examined job and personal resources' moderating effects between role overload and wellbeing outcomes of an international knowledge- based worker sample, recruited from a crowdsourcing platform. Data patterns in Study 1 seem to show that some participants in the intervention group have reported a slight increase in resources and wellbeing, while the control group has mostly reported negative changes. Furthermore, results in Study 2 show positive associations between resources and wellbeing. Psychological safety and coworker support were negatively associated with burnout and positively to wellbeing, with psychological safety moderating the negative impact of workload on wellbeing. These understudied resources appear to be important to support higher wellbeing and lower burnout, warranting further longitudinal research. Organisations are encouraged to foster a workplace culture rooted in psychological safety, where employees feel supported and comfortable seeking help, alongside investing in the enhancement of emotional regulation skills, stands to yield significant benefits for both employees and organisations.
  • ItemOpen Access
    Measurement of seed velocity with a mmWave radar
    (2023) Taylor, Aston T.
    Radar has long been used to measure the range and velocity of different targets, starting from planes in the Second World War through to autonomous car control in the 21st century. The research for this thesis took these abilities and applied them in a novel manner using an IWR6843ISK mmWave radar unit from Texas Instruments to measure the falling speed of two varieties of tree seeds. Initial testing showed the first setup for the IWR6843ISK was inappropriate for velocity measurements over a small distance. However, continued development showed the radar system could quickly and accurately measure a seed’s range over its fall time. After identifying and fixing a well-hidden coding error that changed the calculated seed velocities. Captured range data was post-processed using least mean square averaging to provide the mean terminal velocity of each seed. The velocities found were validated by using timing and frame counting from highspeed camera footage during radar-recorded drops to prove the system was correctly calculating the falling speed. This thesis was sponsored by Tait Communications to build knowledge of mmWave radar systems at the University of Canterbury.
  • ItemOpen Access
    [REDACTED]: An Investigation into the Psychology of Censorship
    (2023) Natasha, Doré
    The right to freely express oneself is a vital component of any democracy. Yet throughout history there have been threats to free expression, often resulting from people trying to find a balance between what views are acceptable to say in public, and what views need to be censored to prevent harm. Given the prevalence of censorship, it is surprising that psychological research in the area is only just burgeoning. Across three chapters, this thesis aims to contribute to the growing literature in two ways: (1) to determine the wider publics’ attitudes towards tolerating versus restricting speech, and (2) how the perceived motives behind someone’s behaviour can influence a person to censor them. Chapter Two addresses the first point, using a person-centred approach to identify people’s endorsement of speech that is perceived as offensive, versus opposing one’s viewpoint. Three profiles were discovered: tolerators (73.2%), who strongly support free speech with moderate-to-low support for banning offensive speech; moderates (24.2%), with mid-level support for both; and censors (2.6%) with low support for free speech, and somewhat high support for banning offensive speech. Chapters Three and Four address the second point. Chapter Three investigates whether people make assumptions about a person’s motives based on their decision to sign a petition to censor a controversial speaker. It was found that people assume an agent holds the same beliefs as a speaker if they refuse to endorse censorship, even when they refused to sign on free speech principles. Chapter Four investigates the perceived motives behind an attempt at reparation. Results revealed that people are more likely to censor someone when they perceive ulterior motives behind the reparation. Thus, this thesis provides evidence that most people are tolerant of speech they disagree with, yet perceived negative motives contribute to many decisions involving censorship.
  • ItemOpen Access
    From powerlessness to empowerment? Exploring the roles of trade union membership and perceived control in protecting employees against the negative psychological impacts of job insecurity
    (2024) Kuluz, Lijana Karin
    Job insecurity has become increasingly commonplace in modern working life and has been associated with negative wellbeing outcomes. The current study aims to expand on current understandings of the relationship between job insecurity and unions, exploring whether aspects of union membership can strengthen employees’ perceptions of control and protect them against the adverse wellbeing impacts of job insecurity. Grounded in appraisal theory, this study examines the potential explanatory role of perceived control in the relationship between job insecurity and poor wellbeing, exploring whether perceived union support and perceived union instrumentality lessen the negative impact of job insecurity on perceived control; and whether job insecurity’s negative impact on indicators of wellbeing – namely job satisfaction, emotional exhaustion and psychological wellbeing – through perceived control, is moderated by perceived union support and instrumentality. Cross-sectional data from 187 international union members was utilised to address these research questions. Results support the explanatory role of perceived control in the relationship between job insecurity and wellbeing. Moderation analyses indicate that at low to moderate levels of job insecurity, those with high union support and instrumentality reported higher perceived control compared to those with low union support and instrumentality. However, when job insecurity is high, even high levels of union support and instrumentality fail to mitigate its detrimental effects on perceived control. This suggests that negative impact of high job insecurity is strong enough that even union support and instrumentality cannot prevent its negative outcomes. Contrary to expectations, results indicate that high perceived union support exacerbates the negative impact of job insecurity on job satisfaction and emotional exhaustion via perceived control. This exacerbating effect may be because job insecurity is perceived as a breach of the psychological contract between member and union. This study contributes to the limited body of research examining the relationship between job insecurity and unions, shedding light on the benefits and limitations of union membership in protecting employees against job insecurity and its negative impacts on psychological wellbeing.
  • ItemOpen Access
    Sand aggradation in Caroline Bay, Timaru.
    (1986) Fahy, F. M. (Felicity Mary)
    This study deals with sand aggradation in Caroline Bay, Timaru. Sand accumulation in the bay, occurring at an average rate of 33,700 m³ y⁻¹, has generally been of a fortuitous nature since it is an unintended consequence of port development, but concern has arisen due to the extent of progradation and associated shoaling. Caroline Bay is a sandy pocket beach that has formed in the lee of habour structures at Timaru, on the otherwise continuous mixed sand and gravel beach complex of the Canterbury Bight. Analysis of historical data was made in order to define trends, rates and patterns of aggradation over the long term. This was combined with study of present day processes of aggradation and erosion, and of the wave and current mechanisms by which sand is transported into the bay. It was found that the beach is prograding at an average rate of 6.0 my⁻¹. Tides deliver sand to the entrance of the bay but they do not play a large part in the transport of sediment thereafter. Dashing Rocks and the North Mole both play an important role in redirecting waves into Caroline Bay. The analysis of sediments revealed that the sand is very well sorted. The beach is a lag deposit of coarser, less transportable gr ins. Finer sand tends to be trapped in the centre of the bay. The beach has a large envelope of change that is progressively moving seaward as well as upwards, so causing the bay to shallow. Short-term horizontal shoreline fluctuations can be up to 60 m per month. From the information provided by these approaches it proved possible to work forward and predict the shore­ line morphology, position and sedimentary nature of an equilibrium shoreline. A computer model was developed to predict the future shorelines. A likely position for an equilibrium shoreline was found to occur 70 m seaward of the present shoreline by about 2000 AD. Management problems, that are posed by aggradation and by wave action around the bay shores are discussed in the light of the major findings of the study.
  • ItemOpen Access
    Genetic structure and conservation of Veronica armstrongii
    (2023) Gibbons, Benjamin
    This study presents the results of an ecological study of the Mt. White population of the Nationally Endangered Veronica armstrongii, and a conservation genomic study of its only two extant wild populations, Mt. White, and Enys Reserve, both located in the Upper Waimakariri Basin, Canterbury New Zealand, as well as V. armstongii plants found in cultivation in New Zealand and Edinburgh. The ecological investigation in this study that took place at Mt. White is a result of field observations that were made at the time of sample collection for the genomic work. It was observed that the health of the plants at different sites at Mt. White were visibly different and the population sizes seen were diminished more than anticipated. There were two sites at Mt. White with healthy plants, Hebe Island in the north of the population and Hebe Terrace a newly discovered site in the South. In between these sites, plants were generally unhealthy, and numbers had declined since the last study there in 2002. This chapter provided an understanding of the current health of the Mt. White population which was used to provide context for the genomic study presented in this thesis. The genomic study of the two remaining wild populations aimed to determine the genetic diversity and genetic connectivity between these populations. There was a large amount of genetic diversity among populations but also a large amount of diversity within populations, with unexpected genetic sub structuring within both Mt. White and Enys Reserve. There also were unexpected genetic similarities between Enys Reserve specimens, plants in cultivation and a representative sample of V. annulata. Lastly, cultivated plants used in my analysis showed no evidence of unique alleles, either because the extinct Rangitata population did not differ from extant populations or because these specimens were not descendants of the extinct population. With this research I would recommend to the Department of Conservation that the wild populations should be managed as separate conservation management units, and that the restoration plantings should be applied to all wild populations. Particularly for each of the unique genetic clusters, this may aid in reducing the wild population decline and possible extinction of V. armstrongii.
  • ItemOpen Access
    A latent class trajectory analysis of family violence perpetration in New Zealand.
    (2023) Jones, Daniel
    Research regarding the long-term continuation, escalation, and desistance of adult family violence (FV) perpetration is sparse, both in New Zealand and worldwide. Understanding patterns of family violence offending across time is of central importance for developing risk-appropriate interventions for FV offenders by ensuring that the risk profiles of offenders are accurately understood. Identification of heterogenous groups of FV offenders also offers the opportunity to provide more personalised interventions to the differing offence patterns being presented, thereby allocating finite intervention resources more efficiently. Furthermore, understanding the variables which predict different patterns of offending may yield important information about unique preventative factors of FV offending for different groups of offenders. In order to address this knowledge gap, the current study utilised New Zealand judicial records to identify the FV offence trajectories of 41,625 adults convicted of at least one FV-related offence. Follow-up data was obtained for at least three years and up to 31 years following the initial FV conviction for each individual. Use of Growth Mixture Modelling techniques resulted in the extraction of two distinct classes of FV offence trajectories – one displaying a consistently low rate of offence, and the other displaying increasing offence rates until the age of 28, where the offence rate declined for approximately 20 years. These findings suggest that the majority FV offenders offend at low rates throughout their lifetime, and that a minority of FV offenders offend at very high rates, particularly frequency around their late 20s. Furthermore, FV offenders who display this high risk pattern of offence tended to be male, Māori, disabled and gang-members more often that those who do not. These findings also suggest that FV interventions may be more effective if they focus on reducing the risk of the high risk offenders, particularly throughout the 20s and 30s when FV offending peaks, because interrupting a FV trajectory at these times would likely cause the greatest reduction of FV instances.
  • ItemOpen Access
    The impact of stormwater on emerging contaminant concentrations in urban waterways: land use and rainfall effects.
    (2023) Oliveira Sarmento, Izaura
    Emerging contaminants (ECs) originating from stormwater runoffs have been an area of increasing concern due to their potentially adverse effects on ecological health. Despite extensive research, gaps remain in understanding stormwater as a primary source of ECs compared to wastewater treatment plants, particularly considering the potential impact of diverse land-use and climatic characteristics. This study aims to fills this knowledge gap by investigating the influence of urban land use and rainfall characteristics on stormwater-derived ECs concentrations in Christchurch, New Zealand. Water samples were methodically collected from Addington Brook (industrial), Bells Creek (residential), and Haytons Stream (industrial and commercial), each unique in their characteristics, and land use. Samples were collected during baseflow and stormflow to identify stormwater contribution. Additionally, ECs concentration changes were monitored throughout a storm event, and a water level logger was used to study its correlation with ECs concentrations. The data analysis revealed the presence of Bisphenol A (BPA) in all catchments, and methylparaben, and the UV-filter 4-Methylbenzylbenzylidene (4-MBC) detected in only a few samples. Among these, only BPA is subject to national and international guidelines. The detected BPA concentrations in this study (7 - 273 ng/L) did not exceed the existing ANZECC guideline values. However, the constant release of BPA into the environment is concerning. Upon evaluating stormwater’s contributions, both methylparaben and BPA demonstrated clear links to stormwater, with methylparaben exclusively detected during stormflow and BPA appearing in both conditions. Contrarily, 4-MBC, detected solely in baseflow, indicated no stormwater contribution. BPA concentrations had fluctuations between baseflow and stormflow conditions, influenced by various factors such as rainfall characteristics and sediment levels. It further highlighted that the presence of personal care products and pharmaceuticals in the environment, particularly methylparaben, was tied to human activities, especially waste disposal practices.
  • ItemOpen Access
    Insights into the behaviours of Scolypopa australis (Hemiptera: Ricaniidae).
    (2023) Borthwick-Taylor, Greer
    Scolypopa australis, commonly referred to as passionvine hopper (PVH), is a major pest impacting New Zealand's kiwifruit industry. Recent research on this insect has predominantly concentrated on innovating new management techniques, particularly the development of vibrational mating disturbance. This thesis delves into various facets of PVH behaviour, shedding light on their implications for future research in this domain. Initially, I investigated the circadian rhythms of PVH vibrational calling behaviour, through laser vibrometry. In this experiment, I examined the likelihood of adult PVH engaging in calling behaviour at different times of day. While my observations indicated an increase in calling behaviour during darker hours, more comprehensive investigations are needed to confirm this pattern. My second experiment sought to ascertain whether PVH exhibited protandry, a phenomenon common in species with similar characteristics to PVH. However, I discerned no significant differences in the emergence timings of adult males and females across the two seasons. Lastly, I explored PVH's preference hierarchies regarding three plant species: māhoe, tomato, and blackberry. This investigation unearthed variations in preferences among the plant options, coupled with differences in preference behaviour between demographics, including nymphs, day-old adults, two-week-old adult males, and two-week-old adult females. While the exact drivers behind these distinctions warrant deeper investigation, it appears plausible that the resemblances I observed between nymph and two-week-old adult female preferences stem from ovipositing females seeking conducive sites to nurture their offspring's development. Furthermore, this experiment unveiled a significant aversion to tomato across all demographics. This revelation opens avenues for employing tomato in intercropping strategies, potentially serving as an additional deterrent for PVH in kiwifruit orchards.
  • ItemOpen Access
    Tweets on the political left and right : a natural language examination of the spread of moral and emotional messaging during the 2018 US midterm elections.
    (2023) Wang, Meng-Jie
    Previous research investigating the spread of political messaging has primarily taken a valence-based approach, leaving it unclear how specific moral or emotional content influences the proliferation of candidates’ messages in a social media context. Moreover, such work does not examine whether any differences exist across major political divides (i.e., Democrats versus Republicans) in their responses to each type of content. Leveraging a large volume of original tweets published by Senate candidates during the 2018 US midterm elections, the current work utilizes natural language processing, combined with machine and deep learning, to explore how candidates' discrete moral (i.e., care, harm, fairness, cheating, loyalty, betrayal, authority, subversion, purity, and degradation) and emotional (i.e., joy, anger, fear, sadness, and confidence) sentiments displayed in a given tweet might be effective at garnering public attention online. In Study 1, while the results indicate that positive joy-signaling tweets were less likely to be retweeted or favorited on both sides of the political spectrum, the presence of specific negative-inducing emotions had a different impact on user responses depending on their political affiliation. Unlike the hypothesis addressed by Jost et al. (2003), i.e., that relatively right-wing individuals report greater responsiveness to fear, threat, or uncertainty, a strikingly opposing pattern emerged in which fear-based messaging among Democrats was more likely to gain attention and spread online. This emotion evoked by Republican candidates, however, did not attract the same degree of attention; instead, anger-inducing information tended to be the content most likely to prompt user engagement on such sites. In Study 2, the results partially support Haidt’s (2012) framework that the political left is more sensitive to care- and fairness-related foundations (compared to the remaining moral foundations), whereas the political right values all five foundations relatively equally. Specifically, the spread of tweets among the political left was driven not only by care/harm and fairness/cheating, but also by other types of moral content, such as those signaling betrayal, subversion, or even degradation. The spread of tweets among the political right, however, accorded more with past research, suggesting that it can be driven by nearly all moral concerns (e.g., ranging from care to purity). Given the ubiquity of social media in contemporary politics, the current work provides a starting point from which to disentangle the role of distinct moral and emotional content in driving the spread of political messaging online, shedding light on the ways in which candidates gain potential exposure through social media communication.
  • ItemOpen Access
    The moderating role of grit in hopelessness and suicide ideation relationships among young men living in New Zealand.
    (2023) Manuel, Ashleigh
    Young males represent the highest at-risk group for suicide completion in New Zealand. Grit has widely been proposed as a potential protective factor for poor mental health, hopelessness, and suicidality. Recent evidence, however, suggests that high levels of grit can also be detrimental to hopelessness. This study aimed to take a nuanced approach to the exploration of the relationships between suicide ideation and attempt, hopelessness, and grit. A community sample of 440 young males living in New Zealand who were aged between 18 to 30 years completed an anonymous online survey measuring both risk and protective factors associated with suicide ideation and attempt. Multiple linear regression and simple slope analyses were used to analyse the relationship between the outcome variables, suicide ideation and attempt, and predictor variables, hopelessness, and grit. Grit was considered as a unitary construct as well as in relation to its contributing factors: grit-interest, and grit-perseverance. Hopelessness was a positive predictor of suicide ideation and attempt in our sample, and grit was shown to be a protective factor against severe suicide ideation. Moderation analyses revealed nuance in the role of grit, as there was a significant positive interaction observed between hopelessness and grit, grit-interest, and grit-perseverance, in that individuals high in both hopelessness and grit were highest in suicide ideation and attempt. Discussions of our findings centre around the importance of considering grit’s protective and risk attributes as context dependant. Further research is needed to replicate these findings, as well as to explore potential mechanisms underlying the relationships observed.
  • ItemOpen Access
    The attentional white bear effect : exploring constraints and its time course.
    (2023) Chen, Makayla Szu-Yu
    We live in a world full of visual stimuli, but only some of them are relevant to our behavioural goals. Although we should in theory process only task relevant stimuli due to the limited attentional capacity, many studies have found that participants allocate attention to expected distractor locations both when the target and distractors appear in the same display (Tsal & Makovski, 2006) and when they appear in different displays (Makovski, 2019). This phenomenon, which is called the attentional white bear (AWB) effect (Tsal & Makovski, 2006) or the preparation effect (Makovski, 2019), is often interpreted in the framework of a process-all mechanism that guides attention to all expected stimuli regardless of task relevancy. However, it still remains unclear whether attention is allocated to expected distractor locations under all circumstances. The present study aims to examine the factors that influence the manifestation AWB effect. In eight experiments, we used a distractor-alone paradigm developed by Makovski (2019). The paradigm consisted of a memory task for most trials and a dot detection task for the remaining trials. The main manipulation involved the presence or absence of distractors during the memory retention interval in different blocks. In the distractor-present block, while participants were holding the memory items in mind, a probe dot was occasionally presented at one of expected distractor locations, and participants made a speeded response once they detected the dot. In the distractor-absent block, the probe dot was presented at an expected empty location. Faster responses to the dot in the distractor-present block compared with the distractor-absent block indicate increased attention to an expected distractor location, ie., the AWB effect. Experiments 1 to 4 examined how task demands and prior experience influenced the AWB effect. In experiments 1 to 3, we varied task demands by requiring participants to hold either fours colours (high memory load) or one colour (low memory load) in the memory task. To assess the effect of prior experience on the AWB effect, we counterbalanced the order of the blocks between participants (distractor-1st group vs. distractor-2nd group) and we analysed their data separately. When the memory load was high, the AWB effect was observed in the distractor-2nd group, but not in the distractor-1st group. When the memory load was low, the AWB effect was found in both groups. In Experiment 4, we again used a high memory load task but eliminated the need for attentional control by replacing the distractors in the distractor-present block with repetitions of the memory items. The AWB effect was found in both groups. These results indicate that participants normally adopt a "process-all" approach, but that top-down attentional control can overrule this approach by suppressing distractor attention if there appear to be insufficient attentional resources to process all the stimuli present. Experiments 5 and 6 replicated the main findings of Experiment 1 with a demanding orientation memory task. Additionally, we investigated the spatial specificity of the AWB effect by presenting the dot in the distractor-present block at either an expected distractor location or an expected empty location (Experiment 5), and we examined the time course of attentional deployment to the expected distractors by presenting the dot before, simultaneously with, or after the expected distractor (Experiment 6). When the AWB effect was present, its magnitude was similar regardless of whether the dot appeared at an expected distractor location or at an empty location. Moreover, attention was deployed 400 ms before the onset of the expected distractors and lasted to at least 800 ms after their offset. These results indicated that in the present paradigm, in which the memory items and the distractors were in separate displays, the AWB effect was neither spatially nor temporally specific. Finally, Experiments 7a and 7b explored the role that abrupt onset of distractors played in the manifestation of the AWB effect. In both experiments, equiluminant stimuli were used such that the onset of distractors was signalled by a change in colour with no change in luminance. The AWB effect was found in both experiments, indicating that the effect was caused primarily by the expectation of distractors rather than by the expectation of luminance increase that typically accompanies the onset of distractors. Taken together, these findings challenge the notion of a mandatory "process-all mechanism" and highlight its susceptibility to prior experience and task demands. While participants generally exhibited diffuse attentional allocation within the distractor display, starting 400 ms before the expected distractor onset and lasting for at least 800 ms, they were capable of overriding this approach when the task required greater attentional resources.
  • ItemOpen Access
    Mixed methods case studies in stress, coping, and contexts during early recovery from substance use.
    (2022) Evans, K. A.
    In this research, I aimed to explore individual’s experiences with stress and coping during early recovery from substance use and the role of context in those experiences. In addition, I sought information about how those contexts and experiences may have changed during the period of early recovery. I utilized a mixed methods case study approach, using inductive and deductive thematic analysis along with questionnaires. These questionnaires measured perceived stress, ways of coping, protective factors, recent risk of problematic substance use, quality of life, and impact of life experiences on wellbeing. Each case study consisted of a narrative depicting an individual’s experience with stress and coping focused on highlighting their unique contexts and how they played a role in those experiences. In addition, their narratives highlighted how contexts may or may not have changed over time. I also presented a brief discussion of how some of the data from the questionnaires triangulated with participants discussed lived experiences to obtain a more holistic understanding of experiences with stress and coping. I found that while everyone did have a unique experience, patterns did emerge across the data, including common environmental systems that played a role in coping and adaptation, similar personal system factors, and utilisations of some similar coping skills, the outcomes, and the impact they had on an individual’s health and wellbeing and recovery differed. The differences in outcomes and impact on health and wellbeing demonstrate that the contexts themselves are not only important to understand experiences with stress and coping during early recovery but also the relationship between those contexts. One of the implications of this research is being able to use the knowledge gained about coping and contexts to help those who are currently in recovery have a higher chance of maintaining that recovery. Other implications include using this research to help those who may be at risk for serve substance use problems before they occur. The results from this study may be able to further support discussing recovery within the context of quality of life instead of dependence or non-dependence. Future directions for research include identifying transitory conditions that may be necessary for those who have yet to enter recovery but display hazardous use, and broadening the criteria to include those who are using but not necessarily in recovery. In addition, further longitudinal studies to identify the exact extent to which coping throughout early recovery changes, how much it changes, and why it changes, especially in groups that may share a common environmental system. As well as potentially looking at relapses as points of transition for the potential for adaptation, instead of being seen as markers of being either in or not in recovery.
  • ItemOpen Access
    Quantifying the reproductive ecology and immune-related gill gene regulation in Stigmatopora macropterygia.
    (2023) O'Neill, Ruby Yve
    The extent of parental investment can significantly influence reproductive success of a species. It necessitates the allocation of precious resources to incubate developing embryos, often prompting adaptations for larger body sizes, and meticulous regulation of immune responses to prevent the rejection of these embryos. Syngnathids are the only known vertebrates to have evolved male pregnancy, making them an invaluable resource for comparative research on the reproductive investments and potential trade-offs exhibited, independent of the female reproductive tract. In this thesis, I explore the reproductive ecology, gill gene expression, and immune sexual dimorphisms in Stigmatopora macropterygia, a pipefish species endemic to New Zealand. Reproductive ecology methods were used to assess the selection gradient for male reproductive success based on body length and width, examine possible sexual size dimorphism, and analyse population sex ratios using field catch data. The results indicate notable variations in female body width in comparison to males, with no significant distinctions in body length between the sexes. Moreover, neither body length nor width appeared to significantly impact male reproductive success. Sampling data highlighted a greater prevalence of females in the population. Genetic analysis, incorporating a differential gene expression analysis, highlights substantial similarity in gene expression patterns between male and female gill tissues. The minimal differential expression between sexes was also reflected in the immune-related genes of the gills. This research provides insight into the complex interplay between morphological evolution and gene regulation in this New Zealand endemic species. It underscores the need to include alternative ecological factors, such as breeding timing, mate preferences, and female size, in shaping male reproductive success. While gene expression remains largely consistent in gill tissues, the identification of exclusive differentially expressed genes in males hints at unique genetic strategies. My thesis not only contributes to our understanding of the evolutionary patterns and reproductive ecology of S. macropterygia but also pave the way for future investigations into the broader evolutionary patterns within syngnathids.