Tuwhera Research Repository

The Tuwhera Research Repository provides sustainable open access and archiving to a broad range of AUT produced research - theses, research outputs and datasets.

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Access status: Open Access ,
“The ED Has Cost Us Our Savings, Home, Career—But Recovery Is Worth It”: Support Needs of Adult Caregivers of People With a Diagnosed or Suspected Eating Disorder in New Zealand—A Mixed Methods Study
(Wiley, 2026-09-26) Sinclair, Rebecca; Landon, Jason; Rowland, Sarah; McDougall, Kahlia; Donkin, Liesje
As most individuals diagnosed with an eating disorder are between 12 and 25 years old, parents or guardians frequently assume a caregiver role. Although caregiving can be rewarding, it is often associated with a high level of burden and requires a correspondingly high level of support. We aimed to examine the support needs of caregivers of people with a diagnosed or suspected eating disorder in New Zealand. Using an anonymous online survey, we asked caregivers about their role, the supports they accessed, and their experiences of these supports. Supports most accessed were support groups, mental health therapists, and self‐help materials. The greatest benefits from the supports were emotional and psychological support, gaining eating disorder‐specific knowledge, and building eating disorder management skills. The main barriers to accessing support were financial, lack of availability, and the individual with the eating disorder being ineligible for support. These findings reflect multiple shortcomings in New Zealand’s health system regarding support available for caregivers. The development of an information hub, use of a standardized screening questionnaire, eating disorder training for healthcare providers, and funding for eating disorder‐related support may help to meet some of the needs highlighted in this study.
Access status: Open Access ,
A Decision-Centered Survey of Machine Learning for Routing in Ad Hoc Networks: MANETs, VANETs, and FANETs
(MDPI AG, 2026-09-25) Liu, Yue; Li, Xue Jun
Machine learning is rapidly transforming routing research across mobile, vehicular, and flying ad hoc networks (MANETs, VANETs, and FANETs). However, cross-study comparison remains difficult because individual works focus on disparate objectives within inconsistent simulation environments. The existing reviews are often organized by algorithmic families, which include Q-learning, deep Q-networks, convolutional and graph networks, and multi-agent reinforcement learning. Consequently, such reviews clearly discuss the model used in a paper yet blur the object of study: the same algorithm may act at many points of the routing decision or replace a protocol such as AODV or GPSR. However, two natural questions arise: how does a design change the routing decision and which learning method implements the change? This survey takes the routing decision itself as the main focus: it unifies vehicular, UAV-swarm, and MANET studies in one decision-centered framework. Under this framework, we survey 92 papers on learning-based routing along five dimensions: (1) the learner’s role and decision authority, (2) the network-state representation it consumes, (3) its information horizon, (4) its temporal horizon, present versus predicted future, and (5) its policy organization and coordination. We provide an evolutionary map, a classification of all 92 papers in the corpus, a mechanism-oriented comparison of trade-offs, and an evaluation audit of a focused 37-paper analytical core. Within this core, the reported results are based on fragmented simulation environments and self-selected baselines: mechanisms can improve performance, but the magnitude of these improvements remains uncertain. We conclude this survey with open challenges that reframe learning-based routing around generalization, prediction reliability, security, reproducible evaluation, and deployability rather than incremental packet-delivery gains.
Access status: Open Access ,
Advancing Research and Innovation in New Energy Technologies [Editorial]
(UK Scientific Publishing Limited, 2026-09-30) Lie, Tek Tjing
The international journal of New Energy Exploitation and Application, launched in 2022, has developed into a forum for disseminating high‑quality research and practical knowledge in the rapidly evolving field of new energy. Since its establishment, the journal has continued to expand its scope, strengthen its scholarly standards, and foster meaningful engagement among researchers and practitioners across the field. The journal publishes innovative research, applied studies, and informed perspectives spanning emerging energy technologies, sustainable energy systems, energy efficiency, and the responsible utilisation of renewable and alternative energy resources. The global transition towards a low‑carbon, secure, and resilient energy future is one of the defining challenges of our time. Addressing this challenge requires not only technological innovation but also interdisciplinary collaboration, informed policy development, effective resource management, and the translation of scientific knowledge into practical applications. Advances in areas such as renewable energy generation, energy storage, smart grids, hydrogen technologies, energy conversion, sustainable transportation, and energy management are creating new opportunities while also introducing complex technical, economic, environmental, and social challenges. The international journal of New Energy Exploitation and Application is committed to providing a platform for researchers, engineers, industry professionals, policymakers, and other stakeholders to exchange knowledge and engage in constructive academic dialogue. The research published in the journal addresses current developments, challenges, and opportunities across the field of new energy. This breadth reflects the importance of research that is both scientifically rigorous and responsive to real‑world energy needs. Through original research articles, review papers, technical studies, and other scholarly contributions, the journal seeks to advance understanding of emerging energy systems and their practical applications. Emphasis is given to research that drives improved energy efficiency, reduced environmental impacts, enhanced system reliability, greater energy access, and the sustainable development of communities and economies. We are deeply grateful to all authors for sharing their research and insights with the global energy community. Our sincere appreciation also goes to the reviewers, editorial board members, and editorial team for their time, expertise, and unwavering dedication to maintaining the journal’s high scholarly standards. Their contributions are vital to our rigorous peer‑review and publication process. We thank our readers for their ongoing interest and support. We hope the research published in this journal will inform current practice, encourage cross‑disciplinary collaboration, and inspire new ideas. Ultimately, we trust that the journal will continue to stimulate innovative solutions and meaningful dialogue among all those working towards a sustainable, reliable, and inclusive energy future.
Access status: Restricted ,
Natural Deep Eutectic Solvent-Based Extraction of SunGold Kiwifruit Polyphenols: Optimisation, Bioactivity, and Functional Application in Yoghurt Systems
(Auckland University of Technology, 2026) Naulidia, Rifqah Azzahra; Yoo, Michelle; Duxbury, Mark
Polyphenols are widely recognised as plant-derived bioactive compounds with potential antioxidant and antidiabetic properties. However, their application in functional foods depends not only on their natural abundance in plant materials, but also on how effectively they can be extracted, retained, and delivered within a suitable food matrix. SunGold kiwifruit is a nutrient-rich fruit containing vitamin C, dietary fibre, organic acids, and phenolic compounds that may contribute to metabolic health benefits. At the same time, yoghurt provides a practical food matrix for bioactive ingredient delivery due to its nutritional value, high protein content, ready-to-eat format, and wide consumer acceptance. Therefore, combining SunGold kiwifruit polyphenols with yoghurt may offer a promising approach for developing functional dairy products with potential antioxidant and antidiabetic properties. Natural deep eutectic solvents (NADES) have recently gained attention as green extraction solvents for plant bioactive because their polarity, viscosity, and hydrogen-bonding capacity can be tailored through solvent composition and water addition. This thesis investigated the use of choline chloride:glycerol-based NADES for extracting polyphenol-rich compounds from SunGold kiwifruit and evaluating their functional application in yoghurt systems. The research focused on extraction optimisation, antioxidant activity, antidiabetic activity, phenolic profiling, and the physicochemical properties of fortified yoghurts. Chapter 2 reviewed the potential of NADES for extracting polyphenols with antidiabetic relevance. The review discussed the classification, dietary sources, and biological activities of polyphenols, particularly their role in carbohydrate-hydrolysing enzyme inhibition, glucose regulation, and antioxidant mechanisms. It also examined the concept of NADES, including the influence of hydrogen bond acceptors, hydrogen bond donors, water content, polarity, viscosity, and extraction conditions on polyphenol recovery. Compared with conventional organic solvents, NADES were identified as promising alternatives due to their tunability and potential compatibility with food applications. However, several challenges remain, including high viscosity, toxicity considerations, regulatory limitations, bioaccessibility, and stability after incorporation into food systems. This review highlighted the need to evaluate NADES not only as extraction solvents, but also as part of functional food development. Chapter 3 optimised ultrasound-assisted NADES extraction of polyphenol-rich compounds from SunGold kiwifruit using response surface methodology. A choline chloride:glycerol NADES system was evaluated by varying NADES molar ratio, water content, solid-to-liquid ratio, extraction time, and extraction temperature. The responses measured were total phenolic content, DPPH radical scavenging activity, ferric reducing antioxidant power, and α-glucosidase inhibitory activity. The fitted models were statistically significant and showed good predictive ability, confirming that extraction variables strongly influenced the recovery and bioactivity of SunGold kiwifruit polyphenols. The optimum extraction conditions were a NADES ratio of 1:1, approximately 50% water content, a solid-to-liquid ratio of 1:20 g/mL, an extraction time of approximately 22 min, and an extraction temperature of 30°C. Under these conditions, the experimental values were 4.892 ± 0.038 mg GAE/g for total phenolic content, 9.797 ± 0.156 mg TE/g for DPPH activity, 9.599 ± 0.129 mg TE/g for FRAP activity, and 2.651 ± 0.024 mg QE/g for α-glucosidase inhibitory activity. LC-MS/MS analysis indicated the presence of several phenolic compounds, including catechin, epicatechin, chlorogenic acid, caffeic acid, and related flavonoids. Chapter 4 evaluated the incorporation of NADES- and water-extracted SunGold kiwifruit polyphenols into yoghurt and assessed their effects on antioxidant activity and physicochemical properties. The extracts were added at different concentrations and at two fortification stages, before fermentation and after fermentation. The water extract showed higher total phenolic content and DPPH radical scavenging activity than the NADES extract, whereas the NADES extract showed higher total flavonoid content, FRAP, and CUPRAC activity. This indicated that the extraction solvent influenced the type of bioactive compounds recovered and that antioxidant activity depended on the mechanism of the assay used. Fortification generally improved the antioxidant properties of yoghurt in a concentration-dependent manner. However, extract type and fortification stage also affected yoghurt quality. NADES-fortified yoghurts generally showed higher pH, higher °Brix, higher viscosity, and lower syneresis than water-fortified yoghurts, suggesting better structural stability. In contrast, water-fortified yoghurts showed greater changes in acidity, colour, and syneresis, particularly at higher extract concentrations. Chapter 5 investigated the in vitro antidiabetic activity of NADES-extracted SunGold kiwifruit phenolics and their application in fortified yoghurt. The NADES extract showed stronger α-glucosidase and α-amylase inhibitory activities than the water extract, with IC50 values of 15.331 ± 0.393 mg/mL and 116.530 ± 2.110 mg/mL, respectively. It also showed greater glucose diffusion retardation, increasing from 35.37% to 62.84% over 180 min, compared with 9.47% to 37.89% for the water extract. When incorporated into yoghurt, enzyme inhibitory activities generally increased with extract concentration, with NADES-fortified yoghurts showing stronger activity than water-fortified yoghurts. The highest α-glucosidase and α-amylase inhibitory activities were observed in NADES-fortified yoghurt prepared by post-fermentation addition at the highest concentration. LC-MS/MS analysis confirmed the presence of several phenolic compounds in the extracts and fortified yoghurts, including catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid. These compounds may have contributed to the observed antidiabetic activity, although the results suggest that the activity was more likely due to the combined effects of multiple phenolics rather than a single compound. Overall, this thesis demonstrated that choline chloride:glycerol-based NADES can be used as a green and functional extraction system for recovering bioactive phenolic compounds from SunGold kiwifruit. Although water extraction was more effective for total phenolic content and DPPH radical scavenging activity, NADES extraction favoured flavonoid recovery, reducing power, carbohydrate enzyme inhibition, and yoghurt structural stability. Compared with yoghurts fortified with the water extract, yoghurts fortified with the NADES extract showed higher responses in several antioxidant and in vitro carbohydrate-digesting enzyme inhibition assays, alongside differences in physicochemical properties. Further studies should evaluate sensory acceptance, storage stability, gastrointestinal bioaccessibility, safety, and in vivo effects to determine whether NADES-based yoghurt products can provide meaningful benefits for glycaemic health.
Access status: Open Access ,
Across Oceans and Into Practice: A Migrant Diversional and Recreational Therapist’s Autoethnography of Belonging, Identity, and Care in Aotearoa, New Zealand
(Auckland University of Technology, 2026) Dudley, Lynette; Hammond, Kay; Lucas, Patricia
This autoethnographic study explores how my immigration journey shaped both my personal identity and my professional practice as a diversional and recreational therapist in Aotearoa New Zealand (AoNZ). Through reflective journaling, storytelling, and critical self-reflection, I examine how experiences of migration, cultural transition, and belonging influenced my deeper understanding of the way I connect with others and deliver therapeutic care within aged care settings. As I navigated unfamiliar cultural spaces and adapted to a new environment, I began to recognise how these experiences deepened my empathy, cultural awareness, and understanding of inclusion in diversional and recreational therapy (DRT) practice. This research reflects on the ways my personal experiences shaped my professional identity and therapeutic relationships. It also highlights the importance of cultural responsiveness, human connection, and reflective practice when working within diverse care environments. By sharing my lived experiences, this study offers insight and encouragement to others working across cultural boundaries and contributes to conversations about identity, healing, and inclusive practice in DRT.