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At what cost?: Qualitative accounts of parents of young Autistic people navigating the transition to adulthood in Aotearoa
(The University of Waikato, 2026-01-12) Dib, Alex; Fox, Ririwai
Neurodevelopmental disorders are paradoxically over diagnosed and underdiagnosed, with autism being one of the most underdiagnosed disorders under the neurodivergence umbrella. Autism spectrum disorder is a neurodevelopmental disorder impacting functioning in social, cognitive, and physical domains. Research suggests that Autistic people experience poorer health and quality of life outcomes, lower academic attainment, higher unemployment, and particularly struggle during the transition from secondary education to adulthood (Shochet et al., 2022). Although an established knowledge base exists in this area, research seldom observes this transition in Autistic people in Aotearoa. Two focus groups were conducted with five mothers of Autistic children (ages 17 to 30). Participants identified key changes to support successful transitions, including greater involvement of people with lived experience in autism services, improved societal education about autism, enhanced diagnostic accuracy, and increased access to ongoing, targeted support. Thematic analysis identified five themes (At what cost, the shortcomings of systemic education, the bio-psycho-social-systemic view of Autistic youth, the transition to adulthood, and the mental health system). The analysis examined predisposing and precipitating factors contributing to adult transition-related obstacles across social, systemic, economic, and family domains. Results from the current study illuminate how Aotearoa-specific factors are impacting Autistic people today. Examining these factors may support the navigation of diagnosis, contribute to ongoing support, and the wellbeing of Autistic young people transitioning into adulthood.
Water quality, phytoplankton, zooplankton and fish in the University of Waikato campus lakes, Hamilton, New Zealand
(The University of Waikato, 2003) Bryant, Nicholas; Hicks, Brendan J.
The water quality, phytoplankton, zooplankton, fish, nutrient regimes, and mixing regimes of three small, shallow, hypertrophic, urban lakes situated on the University of Waikato campus, Hamilton were investigated. The lakes are spatially very close, in the same soil type, subject to the same climatic influences, and have similar nutrient concentrations. However, two of the lakes are shallow (Oranga and Knighton lakes - maximum depth 0.7m) and one of the lakes is slightly deeper (Chapel Lake - maximum depth 1.8m). The lakes experienced strong temperature induced mixing. The water columns of the lakes were less stable at night than during the day. They were more stable in summer than in winter. The water column of Chapel Lake was significantly more stable than Oranga and Knighton Lakes. Oranga Lake was significantly more stable than Knighton Lake. The concentrations of PO₄, NH₄, NO₂, and NOₓ varied over the sampling period but were generally similar in all three lakes. Peaks of NH₄ occurred in Knighton and Chapel lakes. It is possible that low levels of dissolved oxygen caused nitrogen to be released from the sediment in the form of NH₄, which was converted to NO₂ and NOₓ once oxygen levels increased. The exact mechanisms causing the changes in nutrient concentrations are unclear. Water quality varied between seasons. Chapel Lake had consistently better water quality than Knighton and Oranga lakes. This was especially pronounced in summer when there were marked blooms of zooplankton and phytoplankton in Oranga and Knighton lakes but not in Chapel Lake. Significant differences were also found in the phytoplankton and zooplankton diversity and abundance between the lakes. Cyanobacteria and Euglenoids dominated the phytoplankton communities in Oranga and Knighton lakes while Chrysophytes and Chlorophytes were dominant in Chapel Lake. Rotifers and small cladocerans dominated the zooplankton communities in all of the lakes. The differences in phytoplankton communities between lakes were more pronounced than the differences in zooplankton communities. Brown bullhead catfish (Ameiurus nebulous) and shortfinned eels (Anguilla australis) dominated the benthivorous fish communities of the lakes. There was a marked seasonal trend in catch rates with more fish being caught in the warmer months. There were significantly more catfish and eels caught in the two shallow lakes than in Chapel Lake, but significantly fewer common bullies (Gobiomorphus cotidianus). In addition, there were small eels caught in Knighton Lake and Oranga Lake in December but not in Chapel Lake. This indicates that shortfinned eels are able to navigate the stormwater system from the Waikato River to reach the lakes. The catch rates of catfish were lower than previous studies and the populations were dominated by fish aged 1-2 years. The catfish populations have the potential to increase. The greater depth of Chapel Lake appears to protect it from the more extreme effects of hypertrophy experienced by Oranga and Knighton lakes. Artificial deepening is the option that is likely to provide the longest lasting improvements to water quality.
Plant stable isotope ratios (¹⁵N) as an indicator of waste water nitrogen uptake
(The University of Waikato, 1992) Miers, Duncan Brian; Silvester, Warwick B.
An investigation was conducted into the processes that result in waste water N enrichment in ¹⁵N and also the use of this phenomenon in tracing the source of plant N in the environment. A study of ¹⁵N enrichment in various stages of a treatment plant was carried out at the Horotiu treatment plant with the Upper Waikato River and Northern Manukau Harbour systems being used in tracer studies in the environment. Waste water NH₄ in the Horotiu treatment plant was found to become progressively enriched as it passes through the various treatment systems. The inorganic NH₄ in the raw dissolved raw effluent has been shown to be enriched by +4.1 ⁰/₀₀. In the anaerobic pond organic nitrogen is mineralised and mixes with the inorganic NH₄ resulting in an increase in enrichment to +10.7 ⁰/₀₀ due to the mass balance of the two materials. In the facultative pond nitrification and possibly NH₃ volatilisation further enriches the NH₄ to +13.3 ⁰/₀₀. In the Upper Waikato River Lagarosiphon major and Enteromorpha nana were used in a ¹⁵N tracer study of the source of plant N due to their presence in both natural and waste water contaminated sections of the river. Ammonium is the major source of N, available to the two plants and is derived from treated waste water and Lake Taupo NH₄. The ¹⁵N abundance of waste water was +7.9 ⁰/₀₀ enriched, while the Lake Taupo source was estimated using the values for a range of upstream plants to be near atmospheric natural abundance (ie. 0.0 ⁰/₀₀). Isotopic fractionation during the assimilation of ammonium in the river appears to be low, this has enabled plant ¹⁵N abundance to be used as indicator of source mixing. A two source mass balance mixing model has been used to determine the origin of N in the two species and indicates that 50 to 100 % of plant nitrogen is from waste water. Treated waste water ammonium has previously been found to be naturally enriched in ¹⁵N, an investigation was conducted to identify the cause of this enrichment and it’s potential use as a natural tracer of biological processing. A study was carried out in the Horotiu Treatment Plant to examine the ¹⁵N enrichment of waste water NH₄ in various systems and isotopic fractionation during the processing of nitrogen. The Upper Waikato River and Northern Manukau Harbour were used in studies investigating the impact of enriched waste water NH₄ on plant N isotopic ratios in the environment. Waste water NH₄ in the Horotiu Treatment Plant was found to become progressively more enriched as it passes through various treatment systems, this has been attributed to the enriched ¹⁵N abundance of the substrate and various processes that interact with N at each level. Raw waste water from the nearby Affcco freezing works enters the treatment plant with a low NH₄ concentration (12.7 mgl⁻¹) derived primarily from blood and faeces and has a ¹⁵N enrichment of +4.1 ⁰/₀₀. In the anaerobic pond protein is mineralised and mixes with the existing NH₄ to produce a much higher NH₄ concentration (106 mgl⁻¹) without significant isotope fractionation, so that the waste water NH₄ enrichment now resembles the value of the new substrate (ie.+10.7 ⁰/₀₀). In the facultative pond nitrification and possibly NH₃ volatilisation further enrich ¹⁵N abundance of NH₄ to +13.3 ⁰/₀₀, this is the level of enrichment in waste water that is discharged from the treatment plant. In the Upper Waikato River Lagarosiphon major and Enteromorpha nana were used in a ¹⁵N tracer study to determine the source of plant nitrogen downstream of the Taupo Borough Pollution Control Plant, discharge into the river. Treated waste water and Lake Taupo, are the major sources of N in the river, with NH₄ being the predominant form available to plants. The ¹⁵N abundance of waste water NH₄ was found to be +7.9 ⁰/₀₀ enriched, while the isotopic ratio of Lake Taupo source was estimated from the range of isotopic values found in upstream plants to be near 0.0 ⁰/₀₀. Isotopic fractionation during assimilation appears to be small, this has enabled the use of a two source mixing model, using the ¹⁵N abundance values from plants and the two N sources, to show that 50 to 100% of plant nitrogen in the downstream section of the river is from waste water (depending on the site). In the Northern Manukau Harbour an attempt was made to apply ¹⁵N methodology to tracing the impact of waste water NH₄ (the predominant source of NH₄ in the harbour) on plant nitrogen. Ammonium is the major form of N assimilated by plants in the northern harbour. Sediment and plant N (from Gracillaria) indicated that there is a significant fractionation during assimilation, which highest near the waste water outfalls from the Manukau treatment plant, where plant N is -1 to +9 ⁰/₀₀ enriched compared with NH₄ c.+20 ⁰/₀₀. The degree of fractionation indicates that only a small portion of the NH₄ in the harbour is assimilated. A study of SOM indicated that ¹⁵N isotopic ratios in the treatment plant were different to the values in the southern harbour (ie. c. -5 ⁰/₀₀ compared with +12 ⁰/₀₀). A mass balance model was used to indicate the mixing of the two sources of SOM in the harbour. Results show that c. 30% of the SOM in the northern harbour is derived from the treatment plant, decreasing to 7% in the harbour mouth where a further mixing with SOM from the southern harbour is apparent.
Investigating RubyGems packages for software supply chain attack susceptibility through socio-technical metadata
(The University of Waikato, 2026) Nair, Shilpa; Kumar, Vimal
Software supply chain attacks targeting open-source package ecosystems have increasingly become prevalent, where the compromise of a single third-party dependency can affect many downstream applications. Existing approaches to supply chain security are largely reactive, focusing on known vulnerabilities rather than identifying packages that are inherently more susceptible to attack. This thesis proposes an attacker-centric risk profiling framework that investigates package-level susceptibility using socio-technical metadata, including dependency structure, ecosystem impact, and maintenance activity. A hierarchical composite scoring framework is developed, with metric weights derived using ROC AUC analysis to produce an interpretable risk score. The framework is evaluated on 79,000 RubyGems packages, including 380 known malicious instances. Results show that malicious packages are more likely to appear in higher-ranked regions of the score distribution, with consistent enrichment over a random baseline. It also shows that supply chain risk is distributed across a broader high-risk region rather than concentrated at the extreme tail. Quantitative evaluation and case study analysis further show that maintenance and impact-related signals offer the best discrimination between benign and malicious packages. The proposed approach, therefore, functions as a prioritisation tool, supporting effective allocation of security effort in large-scale ecosystems.
Word by word: Reclaiming te reo Māori through Huia Publishers’ translingual children’s picturebooks
(Linguistic Society of New Zealand, 2025-11-28) Barbour, Julie Renee; Joseph, Darryn; Daly, Nicola; Price, Te Kani; Tahau-Hodges, Pania; Teepa, Kawatea; Vanderschantz, Nicholas; Waitere, Eboni; Walker, Bryony
Te reo Māori, Aotearoa’s Indigenous language, is spoken by a growing number of people (Lane 2024), with more than 30% of the total population reporting being able to speak more than a few words or phrases of the language and nearly a quarter of Māori being first language speakers (StatsNZ 2022). The resurgence of the language is taking place in a context of intensive language revitalisation which gained momentum in the 1980s (King 2018). For people who identify as Māori, but who have been denied access to their heritage language, the reclamation of te reo Māori can be traumatic (Hamley 2023). Children’s picturebooks created by Māori content creators offer a way to access Māori language (Daly 2025), supporting the reclamation of te reo Māori and and growing understandings of te ao Māori. HUIA Publishers (n.d.), established in 1991, is a leading Indigenous publisher in Aotearoa. HUIA’s English language picturebooks, produced for a non-Māori speaking audience, are commonly translingual, interweaving Māori words and phrases. In this paper, we examine kupu Māori in HUIA’s picturebooks. Accessing their catalogue of trade publications from a period of more than 30 years, we extracted kupu Māori and undertook a semantic domain analysis to understand the types of kupu Māori that are included. We identify semantic domains that are variously enduring, transient, and newly emerging, and we explore the types of vocabulary that populate each semantic domain. Our research departs from the established literature concerning New Zealand English by positioning kupu Māori in translingual picturebooks as tokens of Māori language, not English, reflecting the languages (and cultures) of HUIA’s content creators. Further, to analyse Semantic Domains, we step away from English categories and instead draw on cultural categories from te ao Māori to classify kupu. Our research demonstrates the wealth of Māori language that is shared through HUIA Publisher’s trade picturebooks. These picturebooks afford opportunities to a Māori audience to begin the process of reclaiming their heritage language. At the same time, they provide opportunities for Pākehā to engage with te reo Māori and te ao Māori.