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Quantitative characterization of the multiscale mechanical properties of low-permeability sandstone roofs of coal seams based on nanoindentation and triaxial tests and its implications for CO2 geological sequestration
No full textMicrostructural heterogeneity of low-permeability sandstone roofs of deep unmineable coal seams due to diagenesis significantly affects rock mechanical behavior, greatly impacting the sealing potential of in situ CO2 sequestration and the structural stability of the geological formation. However, little is known about how the microstructure of different mineral groups influences the multiscale mechanical behavior of deep sandstone. This study proposes a new method for quantitatively characterizing the multiscale mechanical properties of low-permeability sandstone and shows the mechanisms responsible for mechanical failure at the micro-, meso-, and macroscale. Triaxial compression tests and targeted nanoindentation tests were conducted to assess the micro- and macroscale mechanical properties of different types of sandstone. The micro- and macroscale experiments were coupled with numerical simulations of compression using a unified cohesive model based on Voronoi polygons to clarify the multiscale mechanical behavior. The results indicate that quartz, the primary mineral component of the sandstones examined, exhibits the strongest micromechanical properties, followed by feldspar, calcite, and clay minerals. Compared to polycrystalline quartz, monocrystalline quartz has a more stable microstructure and is mechanically stronger. The macro-mechanical properties of tight sandstone samples are weakened by increased microstructural inhomogeneity and larger grain size. This leads to a higher likelihood of splitting damage, characterized by a high degree of discrete and weak stress sensitivity. The major conclusion is that the positive rhythm lithofacies of medium-grained sandstone to siltstone are the most favorable for efficient CO2 sequestration in deep unmineable coal seams
Policy solutions to social housing stigmatisation in Aotearoa
No full textThis policy brief discusses social housing stigmatisation as a process and experience that has detrimental effects on social housing tenants. The brief also highlights the role social housing policy must play in addressing stigmatisation, thereby, ensuring the wellbeing and community inclusion of social housing residents. The discussion and recommendations in this brief are based on a review of evidence for the WERO (Working to End Racial Oppression) research project, examining how neighbours’ perceptions as well as policies and practices of social housing provision impact social housing tenants’ experiences of wellbeing and neighbourhood inclusion
A new journal for a new era
No full textIt is with great excitement and anticipation that we introduce the inaugural issue of the Journal of Psychology and AI. In this period in history where the pace of technological advancements is rapidly transforming every facet of human life, a journal dedicated to the implications of artificial intelligence (AI) for psychology and human behaviour is not only timely but essential
Extreme political narratives: A response to Spear’s “Narratives that Divide and Narratives that Bind”
No full textAndrew Spear (2025) provides a useful and sympathetic account of our thoughts about narratives that arise in those with extreme political convictions (Ulatowski and Lumsden 2023). Indeed, his very title: “Narratives that Divide and Narratives that Bind,” gets to the heart of what we are attempting to do with our narrative account of political extremism The narratives that bind are those political narratives that unite the members of a group not only by being held in common but by entering into those individuals’ narrative identities. The narratives that divide are the kind of narratives rooted in a form of rejection of the opposing group in a way that insulates itself from the reasoning that such a group might provide. Those two characteristics of narratives can be two sides of the same coin; the binding among members of the group can rest on the rejection of an opposing group
Local Cryo-history: Redefining the creation, transformation and circulation of Aotearoa’s nineteenth century glacier knowledge
No full textThe creation, transformation and dissemination of knowledge constantly shapes the narrative of glacier history. However, the intersecting layers that human encounters with the frozen environment, Indigenous knowledge, and popular thought add to glacier histories is often overlooked. By analysing the trends and intellectual traditions that emerged in nineteenth century New Zealand, a period defined as glaciology's 'classical' era of study, this thesis aims to broaden the Southern Alps’ local science-focused glacier discourse.
Māori, for example, possessed unique mātauranga (knowledge) that was documented through Europeans employing local guides to accompany them across the Southern Alps. This mātauranga shaped some encounters nineteenth-century scientists, surveyors, and travellers had with Kā Tiritiri o te Moana’s glacier environment. New Zealand scholars like Julius von Haast and James Hector, on the other hand, further refined their understanding of New Zealand glaciers through the transnational exchange of knowledge and intellectual debates. A combination of Enlightenment rationalism and Romantic aesthetic also influenced popular glacier narratives that emerged during the nineteenth century. For example, the imagination of journalists, mountaineers and travellers reflected the broader cultural trends that circulated from Europe to New Zealand before their knowledge was disseminated to the public.
By interrogating mātauranga Māori, formal scientific study, and popular settler imagination about glaciers, this thesis redefines New Zealand’s nineteenth-century glacier history as inherently multilayered through the circulation, creation, transformation and dissemination of glacier knowledge. In doing so, it highlights glaciers not only as physical entities defined by scientific study but as ideas shaped by diverse knowledge systems, cultural perceptions, and historical contingencies
Characterization and adsorption performance of New Zealand biochar for the removal of paracetamol and ibuprofen from synthetic solutions in batch and column systems
No full textPharmaceuticals are a significant class of emerging organic contaminants that have been increasingly detected in aquatic environments. Their persistence and limited removal by conventional treatment methods poses considerable risks to both flora and fauna. The study investigates the adsorption performance of New Zealand-sourced biochar both raw and surface-modified for the removal of two widely used pharmaceuticals, paracetamol and ibuprofen, from aqueous solutions. With its local availability and carbon-rich structure, biochar was evaluated as an innovative solution to address the growing challenge of emerging pharmaceutical pollutants in aquatic environments. The research aimed to characterize the physicochemical properties of biochar and evaluate its adsorption capacity under batch and column configurations, addressing removal efficiency, equilibrium behaviour, kinetic mechanisms, and dynamic breakthrough performance. The biochar was instrumentally analysed by BET surface area analysis, Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDX) to examine the biochar’s surface structure and functional groups. Premium Biochar demonstrated the highest BET surface area (308.3 m²/g), which further increased to 354 m²/g after 30% KOH activation, indicating enhanced porosity and improved availability of adsorption sites. Batch adsorption experiments revealed that paracetamol achieved higher removal efficiencies and adsorption capacities (up to 8.5 mg/g) compared to ibuprofen (maximum of 2.8 mg/g), largely due to its smaller molecular size and greater polarity. The non-linear technique using isotherm and kinetic model was used to validate the process efficiency of pharmaceuticals removal. Kinetic modelling indicated pseudo-second order and Elovich models best described the adsorption mechanisms (R² > 0.997), confirming chemisorption on heterogeneous surfaces as the dominant process. Isotherm analysis showed multilayer Freundlich adsorption for paracetamol and monolayer Langmuir adsorption for ibuprofen reflecting differences in multilayer versus monolayer adsorption behaviour. Column experiments were conducted under single-pass, closed-loop recirculation, and semi-continuous dosing modes. Single-pass continuous flow showed in rapid breakthrough at short empty bed contact times (1.6–4.5 minutes) due to hydraulic limitations. In contrast, closed-loop recirculation columns achieved up to 90% paracetamol removal and 58% ibuprofen removal under extended operation, specifically, the optimal condition when using 1 mm particle size KOH-activated biochar (1 mm KOH-modified biochar, 15 L/min flow, 500 min runtime). Semi-continuous dosing experiments demonstrated gradual adsorbent saturation with final adsorption capacities of approximately 0.43–0.57 mg/g, supporting the need for regeneration strategies in long-term applications
Investigation of O-acetylserine sulfhydrylase enzymes from bacterial pathogens as potential drug targets
No full textAntimicrobial resistance (AMR) has emerged as a formidable global health crisis, necessitating the urgent development of novel antimicrobial strategies. Among the most concerning drug-resistant pathogens are Neisseria gonorrhoeae and Staphylococcus aureus, both of which lack a functional sulfate reduction pathway, rendering them reliant on alternative sulfur acquisition mechanisms. A key enzyme in the de novo biosynthesis of L-cysteine, O-acetylserine sulfhydrylase (CysK), represents a promising target for antimicrobial intervention due to its essential role in sulfur metabolism and bacterial survival. This thesis presents the first comprehensive biochemical and structural characterization of CysK from N. gonorrhoeae (NgCysK) and S. aureus (SaCysK), providing critical insights into their enzymatic function and potential for therapeutic targeting.
In this thesis, we present the structural characterisation of NgCysK and the model used for structure-based virtual inhibitor screening to identify potential NgCysK inhibitors. Virtual screening produced five hit compounds that were tested in vitro, giving compound 5 with inhibition in the mid micromolar range. Analysis of compound 5 docking indicates interactions with the NgCysK active site residues through hydrogen bonds and supporting hydrophobic interactions. This is the first reported inhibitor of NgCysK and provides a promising starting point for developing new antimicrobial adjuvants for treatment of gonorhoea infections.
Utilizing kinetic assays and small-angle X-ray scattering (SAXS), we elucidated the catalytic properties and structural dynamics of NgCysK and SaCysK, demonstrating their distinct substrate specificity. SAXS analysis indicates both enzymes are a single dimeric species in solution with no conformational changes during substrate binding. Combined with gel chromatography analysis, we showed the inability of N. gonorrhoeae to form the cysteine synthase complex by SAXS analysis.
Overall, this research underscores the significance of CysK as a viable antimicrobial target, contributing to the broader efforts of combatting AMR through metabolic pathway inhibition. By integrating structural biology, enzymology, and computational drug discovery, this thesis advances our understanding of bacterial sulfur metabolism and lays the foundation for the rational design of next-generation antimicrobial therapies against drug-resistant N. gonorrhoeae and S. aureus
Combining Hydromorphic and Shape-Shifting Effects for Programmable Passive Actuation in 4D-Printed Biocomposites
No full text4D printing involves the fabrication of structures that respond dynamically to external stimuli. While various actuation mechanisms have been extensively studied, the integration of multiple actuation effects remains relatively unexplored. This study examines the combined influence of hydromorphic and shape-shifting effects in a biocomposite containing 40 wt% cellulose fibres. The biocomposite was combined with polylactide (PLA) and processed via 3D printing to produce bi-material strips, which were then comprehensively analysed for their material properties and shape-changing behaviour. Upon immersion in water, the biocomposite expanded by 3.2 % perpendicular to the printing direction and exhibited a marked decrease in Young’s modulus with increasing water content. Bi-material strips 1 mm thick displayed pronounced hydromorphic behaviour, achieving maximum curvatures of 0.036 - 0.052 mm-1 depending on the passive-to-active layer thickness ratio. Thicker strips (4 mm) reached 0.012 mm-1 under the same conditions. When both heat and water were applied as external stimuli, the biocomposite and neat PLA layers became simultaneously active, and curvatures of up to 0.057 mm⁻¹ were obtained for 4 mm strips. This curvature surpassed the hydromorphic-only and shape-shifting-only responses by factors of 4.77 and 1.82, respectively. The results demonstrate that integrating water- and heat-induced stimuli increases achievable curvature and accelerates the response, enabling high-curvature deformations even in relatively thick structures. The approach therefore holds promise for applications that demand significant shape transformations without compromising structural integrity
‘You had so much fun!’: Examining associations between positive affect during past and future conversations and children’s self-esteem and optimism
No full textAim: The current study aimed to examine associations of positive affect during caregiver-child past and future event conversations with psychological well-being, focusing on optimism and self-esteem. This study uniquely extends the exploration of caregiver-child conversations to middle childhood and includes discussions about future events that have not been previously examined. Furthermore, it explores the association of conversation content between parent and child optimism and self-esteem.
Method: Participants were 51 dyads; children aged either 11 or 12 years, and their primary caregivers. Parental optimism was assessed using the Revised Life Orientation Test (LOT-R), while child optimism and self-esteem were measured using the Youth Life Orientation Test (YLOT) and Harter's global self-worth items, respectively. Children and caregivers took part in a conversation task in which they discussed past and anticipated future events, capturing positive and negative experiences. These conversations were transcribed and analysed using Linguistic Inquiry and Word Count (LIWC-22) software, to evaluate the use of both positive tone and positive emotions.
Results: A series of correlations and hierarchical regression analyses were conducted. Findings did not demonstrate a significant relationship between parental use of positive affect and children’s well-being outcomes. However, a positive association was identified between children’s use of positive tone in future negative conversations and their optimism, and children’s use of positive tone in positive past conversation and their self-esteem.
Implications: These findings provide preliminary support for parent-child conversation as a context within which self-esteem and optimism may be expressed. These findings highlight the need for future studies with more comprehensive coding schemes to explore the nuances of positive affect in caregiver-child dialogues, particularly with respect to the broaden and build theory of positive emotions. This research contributes to our understanding of emotional dynamics in family interactions and may ultimately have implications for developing targeted interventions to enhance child and adolescent well-being
Whāingaroa/Raglan and positive youth development - Community-driven youth support in Whāingaroa: A case study of the Whāingaroa Youth Work Collective
No full textThis research explores the development and impact of community-driven youth support in Whāingaroa, a rural community in Aotearoa/New Zealand, through an in-depth examination of a local youth work collective. By employing a qualitative, participatory research methodology, the study investigates the complex dynamics of youth empowerment, community engagement, and cultural responsiveness within a unique local context.
The study traces the evolution of the Whāingaroa Youth Work Collective (WYWC) from its inception to its status as a structured community organization. Data collection spanned two years, encompassing six WYWC collective meetings and three focus groups with key collective members. Through ethnographic observations and collaborative research methods, the study illuminates the processes of youth development and community support emerging from grassroots, volunteer-driven initiatives. Thematic analysis was employed to analyse the data, which was categorized into two primary themes: (1) the collective's purpose and operational methodology, and (2) necessary future steps to address gaps in local youth support. These themes were analysed in relation to two research questions:
• How can Whāingaroa/Raglan services support youth at a community-based level?
• What initiatives could be implemented to foster positive youth development in the future?
The findings are presented in two main sections. The first examines the collective's strategy, operational framework and current initiatives demonstrating the effectiveness of locally-based youth support. The second explores the collective's aspirations for future initiatives, specifically focusing on two key proposals: establishing a full-time youth connector position and developing a community youth hub.
Key findings demonstrate the transformative potential of volunteer-driven, culturally responsive youth support strategies. The research highlights the importance of contextual understanding, community ownership, and holistic approaches to youth development. Particularly significant is the model's ability to navigate the bicultural landscape of Aotearoa, providing a nuanced approach that respects both indigenous and contemporary cultural frameworks.
Theoretically grounded in Positive Youth Development (PYD) frameworks and indigenous cultural perspectives, the research bridges Western psychological approaches with local cultural understanding. The study reveals how a community-centric model of youth support can effectively address the complex needs of rural youth, emphasizing cultural identity, collective empowerment, and local knowledge.
The study contributes to broader discussions on youth support, community development, and cultural resilience. It challenges traditional, standardized intervention models by showcasing the effectiveness of locally embedded, flexible support strategies. The research provides valuable insights for community organizations, policymakers, educational institutions, and social service providers seeking innovative approaches to youth engagement.
Further, the findings offer a replicable framework for understanding and supporting youth development in rural contexts, with broader implications for community support strategies that prioritize local knowledge, cultural responsiveness, and collective empowerment.
Ultimately, the research presents a compelling argument for understanding youth development as a collaborative, contextually embedded process. It demonstrates that meaningful community support emerges from within, driven by local aspirations, cultural understanding, and collective investment in young people's potential