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Rethinking Democracy and Detective Fiction: The Legacies of Haycraft’s Wartime Writings
No full textPeer-reviewe
Neighboring extremal optimal control theory for parameter-dependent closed-loop laws
No full textThis study introduces an approach to obtain a neighboring extremal optimal control (NEOC) solution for a closed-loop optimal control problem, applicable to a wide array of nonlinear systems represented by differential equations with affine input coupling, and performance indices that are not necessarily quadratic. The approach involves investigating the variation incurred in the functional form of a known closed-loop optimal control law due to small, known parameter variations in the system equations or the performance index. The NEOC solution can formally be obtained by solving a linear partial differential equation, akin to those encountered in the iterative solution of a nonlinear Hamilton- Jacobi-Bellman (HJB) equation. Just as Galerkin numerical procedures can be used for solving these latter nonlinear equations, we propose a Galerkin-style algorithm for solving the associated NEOC linear partial differential equation, leveraging the use of basis functions that might have been used to solve the underlying HJB equation of the original optimal control problem. The proposed Galerkinbased approach simplifies the NEOC problem by reducing it to the solution of a simple set of linear equations, thereby eliminating the need for a full re-solution of the adjusted optimal control problem. The variation to the optimal performance index is obtained as a function of both the system state and small changes in parameters, allowing the determination of the adjustment to an optimal control law given a small adjustment of parameters in the system or the performance index. Furthermore, we demonstrate the application of the NEOC approach to a simple LQR case, which offers a computationally efficient alternative to directly re-solving the Riccati equation. Moreover, in order to handle large known parameter perturbations, we propose a forward Euler-method that breaks down the single calculation of NEOC into a finite set of multiple steps, each associated with a small parameter variation. Finally, the validity of the claims and theory is supported by theoretical analysis and numerical simulations. (c) 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Peer-reviewe
Future directions for Indigenous One Health: Presenting a conceptual Indigenous One Health model
No full textBackground: This article presents a conceptual Indigenous One Health model to assess health risks that sit at the One Health interface (across animal, human and environmental health) and implement holistic health approaches within Indigenous community settings. Methods: The model is informed by foundational research undertaken at international, national and community-levels that utilised Indigenist approaches, and involved conceptualising animal, human and environmental health considerations together in relation to Aboriginal and Torres Strait Islander health and wellbeing in Australia. Results: The conceptual Indigenous One Health model centres Indigenous cultures, values and knowledge associated with One Health in Indigenous communities and highlights structural needs and principles for implementation. Conclusion: This article discusses key considerations for the future directions of Indigenous One Health, which are required to move the Indigenous One Health research field forward and support health equity in Indigenous communities.Tamara Riley was supported by the Lowitja Institute to undertake this research. Raymond Lovett is supported by the National Health and Medical Research Council of Australia (grant number 1122273). Bonny Cumming is employed by AMRRIC – an organisation supported by the Australian Government as well as various government grants and philanthropic sources.Peer-reviewe
Operationalising the concept of critical natural capital to understand and manage nature dependency risk
No full textHuman dependency and use of ecosystem services have led to the depletion and degradation of natural capital, putting human wellbeing and economic prosperity at risk. The concept of critical natural capital offers a pathway to better understand and manage dependencies and inform government policy by supplementing existing management of environmental impacts. This paper reviews the existing definitions and frameworks for determining critical natural capital and proposes a new approach, informed by global accounting standards, that can be operationalised in Australia and other country contexts. We propose that the primary concern for identifying critical natural capital is determining what is most important, for whom and for what purpose, at a given point in time. A hierarchical importance framework is suggested to identify critical natural capital and ecosystem services that are essential to human wellbeing. Historically, key vulnerability factors such as substitutability, scarcity and threats were also proposed to identify critical natural capital. We argue that these factors should be omitted from the identification process and instead be included in subsequent risk assessments and associated policy processes. This means that the initial identification of critical natural capital should not automatically lead to conservation or protection. Rather, practical operationalisation necessitates that a range of policy options be considered. The proposed framework enables explicit and proactive management of nature-related dependency risks of interest to governments, complementing evolving efforts in the private sector.Peer-reviewe
Feasibility and acceptability of an adapted WHO alcohol brief intervention: Pilot of a three-armed randomized trial in Sri Lanka
No full textBackground Risky drinking (RD) is a major health hazard in Sri Lanka. Alcohol brief intervention (BI) has been proven effective in minimizing RD but has not been utilised in Sri Lanka. We therefore aimed to adapt the WHO alcohol BI and targeted educational material to Sri Lanka, assess their feasibility and acceptability and evaluate appropriateness of methodology and measures for a future RCT. Study design A three-arm parallel-group pilot RCT. Methods The BI was adapted based on expert feedback. The study included male inpatients (with AUDIT-C screening score ≥5) of a tertiary hospital. The three study arms were: adapted brief intervention (ABI), education about unit of alcohol (UOA), and feedback on screening results (FOA). Trained research assistants (RAs) screened and implemented the interventions. We report on follow-up rates (feasibility), participant and RA feedback (acceptability), recruitment efficiency and data quality (methodological appropriateness), and appropriateness of outcome measures. Results The ABI included a structured training manual for implementers, an alcohol information leaflet, and a personal information sheet. Patient follow-up rates were 69 %, 40 % and 71 % for FOA, UOA and ABI arms respectively. Family member recruitment was 31 %. Patient and RA feedback for ABI was overwhelmingly positive. Many patients were abstinent at baseline (37.5 %) and follow-up (75.9 %), mainly due to health concerns. FMQ revealed high ‘total family burden’. Patients struggled with TLFB recall. High childhood adversity prevalence (95.7 %) and low alcohol knowledge were observed. Conclusions The ABI demonstrated high acceptability among patients and RAs. All three interventions could be trialled in a future RCT. All measures except TLFB proved appropriate. Our innovative approach of evaluating outcomes from family members' perspectives proved feasible and valuable. The inpatient setting was not appropriate, rather a setting where patients continue their day-to-day activities, including usual drinking, should be considered in a future RCT.The study was funded by the Romaine Rutnam scholarship of the Australian National University, Canberra, Australia.Peer-reviewe
Spatial distribution of and socio-ecological risk factors for strongyloidiasis in Australia
No full textPeer-reviewe
Advanced MHD Simulations of White Dwarf Mergers and Thermonuclear Transients
No full textWhite Dwarfs (WDs) -- particularly those in binary systems -- represent a vital research topic in modern astronomy. WD binaries are believed to play a key role in numerous areas, including supernova explosions, galactic chemical evolution, the formation of highly magnetic compact stars, and the gravitational wave background. Advanced magnetohydrodynamic (MHD) codes, coupled with increasing computational resources, now allow astronomers to numerically model WD interactions with improved resolution, extended timescales, and more sophisticated physical processes. Higher dimensionality, more realistic chemical compositions, and larger nuclear reaction networks all contribute to reconciling models with observations. In this thesis, I simulate a variety of WD interactions using new physics-rich simulation frameworks. I employ the moving mesh MHD code AREPO to conduct hydrodynamical simulations and adopt realistic chemical profiles for the WD structures. The first part of the thesis develops a pipeline for generating chemically and thermally self-consistent WD structures using the WDEC code. These structures are used to simulate the merger of a carbon-oxygen WD with a low-mass helium WD, resulting in an edge-lit detonation that produces asymmetric ejecta dominated by Ni56, Si28, and S32. Variation in inspiral rates strongly affects the outcome: slower inspirals produce surviving high-velocity helium WD companions consistent with observed hypervelocity WDs, while faster inspirals lead to a disruption of the companion via extreme tidal forces. These results highlight the importance of physically accurate pre-merger structures and angular-momentum evolution in merger modelling. Subsequent simulations focus on mergers between an oxygen-neon (ONe) and a helium WD using detailed ONe profiles generated with LPCODE. A thermonuclear runaway is triggered at the base of the helium layer, producing about 0.103 solar masses, of ejecta with compositions characteristic of faint, rapidly evolving transients similar to a supernova of type ".Ia". Comparison with simplified constant-composition models shows that neglecting realistic abundance profiles can yield unphysical double-detonation pathways. The outcomes of these models strengthen the link between helium accreting ONe WD systems and observed sub-luminous thermonuclear transients. The final part of the thesis examines how chemical distillation of Ne22 during WD crystallisation alters explosion nucleosynthesis and observables. Artificial detonations of Ne22-enriched core and shell models produce enhanced yields of neutron-rich isotopes such as Ni58, Ni59, and Co55. Spectral differences are only modest at early times but become potentially distinctive in the nebular-phase, where forbidden lines of iron-group elements emerge. Distillation also increases the B-band decline rate without greatly reducing peak luminosity, offering a possible explanation for bright, rapidly declining SNe Ia. These results demonstrate that the evolution of internal composition can leave detectable imprints on explosion products and light curves. Collectively, this work provides new insights into the conditions leading to WD detonations and the diversity of the resulting transients. It underscores the importance of using physically consistent initial models, realistic chemical stratification, and coupled hydrodynamic-nucleosynthetic approaches in simulating thermonuclear events
Acceptability and Effectiveness of Behavioural and Non-Behavioural Parenting Interventions for Child and Adolescent Mental Health
No full textMental health problems have widespread impacts on children and adolescents ("youth"), their families, and society. Parenting represents one of the most modifiable and proximal targets for supporting youth mental health. Accordingly, decades of research have examined various theoretical approaches to parenting interventions, which can be broadly categorised as behavioural and non-behavioural parenting interventions. Behavioural parenting interventions rely on social learning principles, whereby, child behaviour is strengthened or weakened through parental reinforcers of attention. These interventions are currently considered the treatment of choice for child externalising problems (e.g., aggression, noncompliance) and also show secondary effects for youth internalising problems (e.g., anxiety, depressive symptoms). Despite the strong empirical support for this model, a core procedure of behavioural parenting interventions, namely "time-out," has received increasing criticism in the community. This has occurred alongside speculation of an apparent paradigm shift towards non-behavioural parenting interventions, specifically attachment- and emotion-focused parenting interventions, which strengthen the parent-child relationship and improve child wellbeing outcomes by helping parents sensitively respond to children's underlying emotional needs behind their behaviour. These interventions have substantial empirical support for improving child secure attachment, caregiver sensitivity, and emotional competence; however, there has been less research attention on the effects of these interventions on youth mental health problems. In particular, the comparative advantages of behavioural and non-behavioural parenting interventions for addressing youth mental health outcomes remains understudied. This thesis included three studies that collectively aimed to examine the effectiveness and acceptability of behavioural and non-behavioural parenting interventions. First, a systematic review and meta-analysis (k=43) on the effectiveness of attachment- and emotion focused parenting interventions found significant small reductions in youth externalising outcomes and small-to-moderate reductions in internalising outcomes. However, the relative effectiveness of these interventions to behavioural parenting interventions remains largely unknown. Second, a survey with 110 practitioners working with children and families found that only 38% of the relevant sample reported using time-out, with some endorsing criticisms of the procedure. Notably, greater knowledge of appropriate time-out implementation was associated with increased time-out use and acceptability. Finally, interviews with 24 psychologists on their broader acceptability and implementation of behavioural and non-behavioural parenting interventions were analysed using reflexive thematic analysis. Results indicated a perceived polarisation between behavioural and non-behavioural parenting interventions in practice; though, not all psychologists were in favour of this. Further, provider-level factors including training, affective experiences, and values played a role in their implementation of parenting interventions. In sum, the findings of this thesis shed light on future research and practice directions in implementing evidence-based parenting interventions for youth mental health problems. Findings suggest that behavioural and non-behavioural parenting interventions are effective and generally acceptable treatment options for youth mental health problems, though, more research is needed to understand the relative effectiveness of these approaches. Furthermore, the misconceptions about behavioural parenting interventions, particularly time-out, warrant attention. Notwithstanding this, it remains essential to consider alternative parenting intervention approaches in research and practice, as inevitably, families' preferences, values, and needs will align with different theoretical approaches
When the strong act, the rules bend: Venezuela and world order
No full textThe strike on Venezuela has sparked debate about sovereignty and legality. But the episode reveals a deeper truth about the enduring explanatory power of foreign-policy realism.Peer-reviewe
The Transition from Service to Civilian Life: Risk Factors, Psychometric Assessment and Intervention for Reintegration and Adjustment of Military Veterans.
No full textBackground: Reintegration difficulties among military veterans transitioning to civilian life is appear common, with maladjustment linked to psychiatric illness and suicide. Despite this, substantial gaps in evidence-based assessments and interventions remain. This research describes the development and validation of the Military-Civilian Adjustment and Reintegration Measure (M-CARM), a post-separation assessment tool used to assess psychological adjustment and cultural reintegration to civilian life, as well as the Mental Readiness for Military Transition Scale (MT-Ready), a pre-separation tool developed to identify psychosocial factors predictive of post-separation adjustment and mental health. Demographic factors associated with adjustment among this population were identified and a novel intervention for veterans targeting adjustment and reintegration was developed and evaluated.
Methods: A two-phase multi-methods approach was employed across five studies. Phase I included interviews and focus groups with veterans (n = 60), partners (n = 20), and clinicians (n = 20). Thematic analysis informed item development, reviewed by an expert panel (n = 12) and piloted with current (n = 19) and ex-serving Australian Defence Force (ADF) personnel (n = 11). Phase II evaluated the psychometric properties of the M-CARM and MT-Ready using a prospective sample of ADF members (n = 345) and a cross-sectional sample of ex-serving members (n = 725). A qualitative sub-study (n = 35) explored employment challenges among veterans using thematic analysis. Finally, an eight-week group program incorporating cognitive-behavioural and acceptance and commitment therapy was evaluated for feasibility and acceptability in a non-controlled within-subjects longitudinal design with transitioned veterans (n = 24).
Results: The M-CARM demonstrated a five-factor structure (Purpose and Connection, Help Seeking, Beliefs about Civilians, Resentment and Regret, and Regimentation) across 21 items. The MT-Ready demonstrated a three-factor, 15-item structure (Future Focus and Optimism; Anger and Perceived Failure; Civilian Connections and Social Support). Confirmatory factor analysis via a split-half sample validated the M-CARM structure. Both measures demonstrated strong reliability and validity, and MT-Ready scores significantly differentiated post-separation outcomes including adjustment, PTSD, depression, anxiety, and quality of life. Veterans with higher odds of maladjustment included those unemployed or on a medical pension, single, male, from lower ranks and education, with higher PTSD symptoms, anger, feelings of failure and being unprepared for transition. Qualitative analysis revealed four themes in civilian employment challenges: starting over, mental health, interpersonal-cultural difficulties, and organisational differences. The program evaluation demonstrated high engagement, experience, usefulness, and improved adjustment. Strong retention (82.8%), completion (87.5%), and fidelity (89.6%) were also found. Significant improvements in M-CARM scores were found from pre-intervention to post-intervention (p = <.001), maintained at follow-up with large effect size.
Conclusion: This research provides evidence for the validity, reliability, and clinical utility of new tools to assess and predict psychological adjustment and cultural reintegration among military populations. Interventions should target high-risk groups including unemployed or medically discharged veterans with psychological symptoms and limited support. The program demonstrated promising feasibility and initial outcomes addressing the psychological and cultural barriers to reintegration and adjustment. Overall, the findings represent a substantial step toward practical, evidence-based support for transitioning military personnel, with implications for assessment, prevention, and intervention at both population and individual levels