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Differences in emotion regulation components underlie the sexual orientation disparity in depressive symptoms: a prospective, population-based study of young adults
(Springer, 2026) Seager van Dyk I; Rutherford CG; Pachankis JE; Bränström R; Hatzenbuehler ML
Purpose Hatzenbuehler’s psychological mediation framework proposes that difficulties in emotion regulation (ER), which are driven in part by excess exposure to stigma-related experiences, contribute to sexual orientation-related mental health disparities. However, existing research on the framework has largely focused on a small number of ER variables in non-probability samples. Methods To address these limitations, we examined whether a large complement of ER components mediates the prospective association between sexual minority status and depressive symptoms, using longitudinal data from a population-based sample of 1,208 Swedish young adults (aged 18–35). Data were collected in 2020 (ER, depressive symptoms) and 2021 (depressive symptoms). Participants completed 12 measures of ER, spanning a diverse array of ER constructs (e.g., emotional awareness, cognitive reappraisal, access to ER strategies). Results Sexual minorities exhibited significantly more ER difficulties on nine out of the 12 ER components, and higher depressive symptoms, compared to heterosexuals. Eight of the 12 ER components independently mediated the association between sexual minority status and increases in depressive symptoms one year later, and two components (brooding rumination, difficulty identifying positive emotions) mediated this relationship when all 12 ER components were entered into the model simultaneously. Conclusion These findings provide evidence from a population-based, longitudinal study that a wide range of ER factors underlie sexual orientation-related disparities in depressive symptoms during a developmental period of heightened risk.
Promoting psychosocial safety climate across school teams: A schoolwide leadership responsibility
(Taylor and Francis Group, 2026-08-27) Cataloni S; Forsyth D; Brougham D; Thorn K
This qualitative case study uses document analysis, interviews, and focus groups to explore how the principal and line managers promote psychosocial safety climate (PSC) across teams in an Aotearoa/New Zealand school. While principals’ support for teachers’ psychological health has been examined, how they support line managers in developing team and individual-level PSC remains unclear. Findings indicate that PSC is not always directly transferred from the principal to teachers but operationalized by line managers, positioning PSC as a multilevel, collectively enacted process. A multilevel model shows how leadership helps operationalize and transfer PSC across school, team, and individual levels.
A*-guided deep reinforcement learning for single- and dual-agent navigation : cross-algorithm evaluation and transformer-based policies : a thesis presented in partial fulfilment of the requirements for the degree of Master of Information Science in Computer Science at Massey University, Auckland, New Zealand
(Massey University, 2026) Liu, Yahong
Integrating classical path planning with deep reinforcement learning (DRL) offers a promising approach for navigation in obstacle-dense environments, where purely learned policies often suffer from sparse rewards, inefficient exploration, unstable con vergence, and collision-prone behaviour. This thesis investigates the integration of the A-star (A*) path-planning algorithm with deep and multi-agent reinforcement learning (MARL), with a particular focus on reproducibility, cross-algorithm evaluation, policy architecture design, and the transition from single-agent to dual-agent navigation. The study builds on previous A*-guided DRL research by reproducing and extending its core ideas within the Vectorized Multi-Agent Simulator (VMAS) and Benchmarking Multi-Agent Reinforcement Learning (BenchMARL) frameworks. The thesis makes four main contributions. First, it establishes a reproducible experimental pipeline for evaluating A*-guided reinforcement learning in navigation tasks. Second, it examines how A*-generated waypoint guidance affects different reinforcement learning algorithms, including Multi-Agent Proximal Policy Optimization (MAPPO), Multi-Agent Deep Deterministic Policy Gradient (MADDPG), and the Q value Mixing Network (QMIX). Third, it evaluates the use of structured waypoint information through a Task-Adaptive Waypoint-Aware Transformer configuration. Fourth, it investigates how A*-guided learning and waypoint-aware policies behave when extended from controlled single-agent navigation to dual-agent navigation. In the proposed framework, A* is used to generate waypoint paths that support reinforcement learning through reward shaping and, in some configurations, through explicit waypoint observation features. For the multilayer perceptron (MLP) baseline and Standard Transformer configurations, A*-derived guidance is used during training and removed during evaluation. For the Task-Adaptive Waypoint-Aware Transformer configurations, A*-based reward shaping is disabled during evaluation, but A*-derived waypoint observation features may remain part of the policy input. The baseline re production shows positive descriptive differences in final-window evaluation reward and the collision-penalty proxy in controlled single-agent settings, particularly in compact obstacle-dense environments. However, the results also show that A* guidance does not necessarily improve sample efficiency or convergence speed and introduces additional computational overhead. Extending the framework to MAPPO, MADDPG, and QMIX reveals that the effects of A* guidance are algorithm-dependent, with different learning paradigms responding differently to planning-derived reward signals. The architectural evaluation shows that a Standard Transformer Policy Baseline does not automatically outperform the Fully Connected MLP Policy Baseline. This indicates that simply replacing an MLP with a Transformer is insufficient for improving navigation performance. In contrast, the Task-Adaptive Waypoint-Aware Trans former shows positive descriptive trends in selected final performance metrics, including higher average-reward and final-window evaluation-reward values in some configurations. However, the five-seed statistical analysis does not establish statistically significant improvements after Holm-Bonferroni correction. The dual-agent experiments reveal an important limitation of directly transferring single-agent A*-guided strategies to multi-agent navigation. While A* guidance reduces collisions in single-agent settings, independently generated A* paths can create inter agent path conflicts in dual-agent scenarios. This produces a qualitative shift in the role of A* guidance: its collision-reduction benefits do not automatically transfer to multi-agent settings, although it may still support generalization and task completion in some cases. The results also show that scaling waypoint-aware Transformer policies to dual-agent navigation increases training difficulty and produces algorithm-dependent effects. MADDPG benefits most clearly from the waypoint-aware architecture, QMIX shows mixed effects, and MAPPO exhibits instability under the tested configuration. Overall, this thesis demonstrates that classical planning signals can provide useful structure for reinforcement learning-based navigation, but their benefits depend strongly on the learning algorithm, policy architecture, evaluation setting, and number of agents. The findings clarify both the potential and the limitations of A*-guided DRL and MARL. They suggest that waypoint-aware Transformer policies are a promising direction for structured navigation learning, while also highlighting the need for larger scale statistical validation, improved multi-agent coordination mechanisms, and more robust approaches for resolving conflicts between independently planned paths.
Effects of plant gender, cutting age, and propagation medium on rooting and growth of Juniperus communis cuttings : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Horticultural Sciences, Massey University, Palmerston North, New Zealand
(Massey University, 2026) Ravipati, Krishna Chaitanya
Juniperus communis L. is a slow-growing, dioecious conifer of increasing ecological and commercial value, but large-scale production is limited by slow, erratic adventitious rooting. The present study examined the influence of cutting age, plant gender and propagation substrate on survival, and growth of J. communis stem cuttings under greenhouse conditions. Shoots were taken from male and female stock plants and divided into one-year-old and two year-old cutting material. Two-year-old cuttings were propagated in rockwool, pumice, peat: perlite (1:1, v/v), and vermiculite: perlite (1:1, v/v) mix, while one-year-old cuttings were propagated in pumice and vermiculite: perlite (1:1, v/v) mix. Survival, root number, root length, and shoot length were assessed over a nine-month period. Plant gender, propagation substrate and their interaction had significant effects on survival at three, five and nine months after planting in two-year-old cuttings. Overall, well-aerated substrates, particularly pumice and rockwool, consistently promoted better rooting performance than vermiculite:perlite. Male cuttings propagated in pumice and rockwool achieved the highest survival rates (80% and 84%, respectively), whereas female cuttings grown in vermiculite:perlite had consistently low survival (12%). Root number was the most responsive growth parameter, with male cuttings in rockwool and female cuttings in pumice producing the highest root numbers. Cutting age influenced the response to both plant gender and substrate. In two-year-old cuttings, survival and root number were significantly affected by gender, substrate, and their interaction. In contrast, one-year-old cuttings showed more uniform rooting responses, with few significant effects of gender or substrate. Root length in one-year-old cuttings was greater in pumice (82.82 mm) than in vermiculite:perlite (64.96 mm) after five months of propagation. Overall, plant gender and propagation substrate had greater effects on rooting performance in two-year-old than in one-year-old cuttings. Well-aerated substrates, particularly pumice and rockwool, promoted more favourable rooting than vermiculite:perlite, while one-year-old cuttings exhibited more consistent propagation outcomes. These findings demonstrate that cutting age, plant gender, and substrate selection should be considered jointly when developing vegetative propagation protocols for J. communis. Developing reliable vegetative propagation methods will support its ecological restoration, conservation, and commercial cultivation.
Work, social support, and meaning in life in older adulthood
(Springer, 2026-07-03) Smith J; Alpass F; Taylor J; Saei R
Meaning in life (MIL) is associated with enhanced well-being but little is known about sources of MIL for older adults. As an increasing proportion of older adults are engaged in employment and volunteer roles, this study aimed to examine the associations between MIL, employment, and volunteering among older adults still working and transitioning to retirement. Additionally, the study sought to examine what it is about these roles that may facilitate MIL, specifically, whether giving social support would mediate the relationships between employment, volunteering, and MIL. This research was based on a large sample of community-dwelling older adults in Aotearoa New Zealand. It was a secondary data analysis primarily using linear hierarchical regression. While participation in paid employment was not associated with MIL, the provision of social support mediated the relationship between paid employment and MIL. Volunteering was associated with higher MIL among older adults and this relationship was also mediated by the provision of social support. Volunteering presents opportunities to provide support for others and may be particularly effective for enhancing MIL among older adults. Further research is needed to investigate how different aspects of employment relate to MIL in order to better understand how employment may be structured to contribute to MIL and how MIL might be promoted among older adults.