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A life stage resolved habitat model for guiding seagrass restoration in coastal lagoons
No full textCoastal lagoons are productive ecosystems supporting diverse biota but are susceptible to altered flow regimes and nutrient enrichment. The Coorong Lagoon in South Australia faces significant threats from reduced freshwater inputs and eutrophication, with the keystone macrophyte species, Ruppia tuberosa, generally in a state of decline. Identifying management strategies to guide their recovery has proven complicated due to the complex environmental requirements across life stages. This study aimed to develop a novel phenology-based habitat suitability model for quantifying the overall probability of reproductive success, based on salinity, water depth, light availability, temperature and filamentous algae presence. High-resolution predictions from a coupled hydrodynamic-habitat suitability model were validated against individual life stage data and reproductive outcomes (sexual and asexual) under both typical and atypical (La Ni˜na) climatic conditions, achieving statistically significant (P < 0.05) correlation coefficients for all life stages under typical conditions. Results revealed considerable inter-annual variability in total areas suitable for reproduction between 2018 and 2022, primarily influenced by salinity and light availability during early stages (germination and sprouting) and reproductive stage. 2018 had the largest suitable areas for reproduction, while 2021 had the smallest. Under typical conditions, the central part of the lagoon was identified as a high conservation value area for R. tuberosa, offering optimal conditions for both sexual and asexual reproduction. This study highlights the importance of incorporating phenology into habitat models and demonstrates how such models can guide management decisions aiming at restoring not just the adult plant phase but also ensuring reproductive success and long-term resilience of the R. tuberosa community.Sherry Y. Zhai, Michelle Waycott, Ryan Lewis, Emma O′Loughlin, Paul L.A. Erftemeijer, Peisheng Huang, Justin D. Brookes, Claire Sims, Zhenming Zhang, Matthew R. Hipse
Exploring the acceptability of a risk prediction tool for cardiometabolic risk (gestational diabetes and hypertensive disorders of pregnancy) for use in early pregnancy: A qualitative study
No full textProblem/ Background: The acceptability of providing women with personalised cardiometabolic risk information using risk prediction tools early in pregnancy is not well understood. Aim: To explore women’s and healthcare professionals’ perspectives of the acceptability of a prognostic, composite risk prediction tool for cardiometabolic risk (gestational diabetes and/or hypertensive disorders of pregnancy) for use in early pregnancy. Methods: Semi-structured interviews were conducted to explore the acceptability of cardiometabolic risk prediction tools, preferences for risk communication and considerations for implementation into antenatal care. The Theoretical Framework of Acceptability informed interview questions. Transcripts were thematically analysed. Findings: Women ≤24 weeks’ gestation (n =13) and healthcare professionals (n =8), including midwives (n = 2), general practitioners (n =2), obstetricians (n =2), an endocrinologist (n =1) and cardiologist (n =1) participated. Participants indicated that providing personalised risk information is only appropriate when preventative measures can be initiated to mitigate risks. Differentiating the risk for each condition (single risk outputs) was often preferred to composite risk outputs to enable targeted monitoring and management. Defining conditions and risks to mother/baby, visually depicting personalised risk scores, and providing clear, patient- centred clinical management plans were recommended. Supportive clinical policy changes, staff engagement/ training, and integration into electronic health records were suggested to facilitate uptake into routine antenatal care. Conclusion: Women and healthcare professionals suggested that early pregnancy cardiometabolic risk prediction tools may be acceptable when preventative interventions are available to reduce risks. Risk prediction tools with integrated patient-centred education materials may promote timely access and engagement with preventative interventions to optimise women’s current and future health.Sarah Lang, Jennifer G. McIntosh, Joanne Enticott, Rebecca Goldstein, Susanne Baker, Margaret McGowan, Shamil Cooray, Lan Du, Anjana Reddy, Cheryce L. Harrison, Eleanor Thong, Kushan De Silva, Helena Teede, Lisa J. Moran, Siew Li
It is time to take a broader equity lens to highlight health inequalities in people with pain
No full textHealth equity means that ‘everyone has a fair and just opportunity to be as healthy as possible’. Although there is widespread recognition that this aspiration must drive efforts to improve the health of individuals and communities, leading medical journals have recently drawn attention to ongoing shortcomings in health research. Typically, the characteristics of participants involved in research do not represent the broad range of sociodemographic characteristics of patients encountered in everyday practice, and under-representation of people who experience disadvantage and marginalisation is commonplace. It is widely recognised that a major contributor to health inequities are the social determinants of health, that is, ‘the conditions in which people are born, grow, live, work and age, and the fundamental drivers of these conditions: the distribution of power; money; and resources’. Developing a contemporary understanding of how the social determinants of health relate to pain experiences and outcomes appears timely and important, and we consider it to be a crucial step towards improving health equity for people with pain.Emma L. Karran, Aidan G. Cashin, Trevor Barker, Mark A. Boyd, Alessandro Chiarotto, Vina Mohabir, Jennifer Petkovic, Saurab Sharma, Peter Tugwell, G. Lorimer Mosele
High-Order Graph Models and their Applications in Active Directory Security
No full textActive Directory (AD) is a directory service for Windows domain networks, managing identity and access control within organizations. Given its widespread adoption— used by 90% of Fortune 500 companies—AD has become a primary target for cyberattacks. Recent studies indicate that over 50% of organizations have experienced AD-related breaches, with 82% of penetration tests successfully exploiting AD vulnerabilities. Despite the increasing frequency of AD attacks, the majority of existing defense solutions remain reactive, addressing threats only after they have been exploited. This reactive approach leaves organizations vulnerable, highlighting the need for defenses that mitigate attack vectors before adversaries exploit them. A major challenge in AD security is its complexity. AD environments can contain hundreds of thousands of users, computers, and groups with intricate permissions. Attack graphs have emerged as a crucial tool for modeling AD vulnerabilities, providing a structured representation of attack paths that adversaries could exploit. By applying security algorithms to these graphs, organizations can identify and eliminate high-risk attack paths to protect critical assets. However, the effectiveness of these defense strategies is inherently limited by the quality of the underlying AD data. Due to the sensitive nature of ADs, few real-world datasets are publicly available, and existing generative tools fail to produce realistic AD attack graphs. As a result, security research often relies on overly simplistic models that do not accurately reflect how AD is constructed in real-world environments, potentially leading to ineffective mitigation strategies. Additionally, conventional attack graph representations follow a node-tonode mapping model, where security relationships are depicted as directed edges, and an edge connects two nodes, representing individual entities. While intuitive, this model does not accurately capture how AD permissions are structured in practice. Real-world access control applies to sets of objects, not individual nodes. Failure to account for this high-order structure involving sets leads to an explosion in graph size with edges connecting individual nodes, dramatically increasing the computational complexity of security algorithms. This inefficiency is particularly problematic in large-scale AD environments, where rapid response to threats is critical and defenders are constrained by a limited number of edges they can remove to minimize the traversability of attackers to high-value assets. To address these limitations, this thesis introduces two key contributions. First, it proposes a generative model for constructing realistic AD attack graphs based on the inherent design principles and security guidelines of realistic AD systems. This generative model enables security researchers to evaluate defense strategies on representative data, bridging the gap between theoretical security measures and real-world applicability. Second, the thesis presents a novel high-order graph model for security permissions, optimizing defense strategies in eliminating attack sources, especially under cyber emergencies. In addition, this thesis proposes the α-Spiral Algorithm, an enhancement on the state-of-the-art Spiral Algorithm in eliminating attack sources in Active Directory. The mathematical proof and extensive experiments show that the proposed graph model, in conjunction with the α-Spiral Algorithm, achieves greater elimination of attack sources while reducing computational overhead compared to the conventional graph model and the original Spiral Algorithm.Thesis (MPhil) -- University of Adelaide, School of Computer and Mathematical Sciences, 202
Conflating "green prescriptions" and "nature prescriptions"
No full textAvailable online 15 January 2025.
Letter to the Editor.Jessica Stanhopea, Philip Weinstei
Structural insights into S-lignin O-demethylation via a rare class of heme peroxygenase enzymes
No full textThe O-demethylation of lignin aromatics is a rate-limiting step in their bioconversion to higher-value compounds. A recently discovered cytochrome P450, SyoA, demethylates the S-lignin aromatic syringol. In this work, we solve high-resolution X-ray crystal structures of substrate-free and substrate-bound SyoA and evaluate demethylation of para-substituted S-lignin aromatics via monooxygenase and peroxide shunt pathways. We find that SyoA demethylates S-lignin aromatics exclusively using the peroxide shunt pathway. The atomic-resolution structures reveal the position of non-canonical residues in the I-helix (Gln252, Glu253). Mutagenesis of this amide-acid pair in SyoA shows they are critical for catalytic activity. This work expands the enzymatic toolkit for improving the capacity to funnel lignin derived aromatics towards higher value compounds and defines the chemistry within the active site of the enzyme that enables peroxygenase activity. These insights provide a framework for engineering peroxygenase activity in other heme enzymes to generate easier to use biocatalysts.Alix C. Harlington, Tuhin Das, Keith E. Shearwin, Stephen G. Bell, Fiona Whela
Teachers’ Perceptions of Critical Thinking Facilitation in English Language Classes in an Indonesian High School
No full textCritical Thinking development in Indonesian secondary schooling has been paired and emphasized in English as an Additional Language in order to respond to global changes and position the nation for better engagement with global concerns. This article presents a qualitative study that investigated in-service teachers’ perceptions about facilitating Critical Thinking in their English language classes in an Indonesian high school through in-depth interviews. Teacher interviews in this study were analyzed with Interpretative Phenomenological Analysis, and the findings revealed that teachers appeared to lack Critical Thinking concepts and were faced with constraints in their English language classes. Substantial obstacles such as inadequacies of students’ English language proficiencies, authentic Critical Thinking materials in English as an Additional Language as well as appropriate assessment tasks also minimized teachers’ efforts in facilitating and developing Critical Thinking in their English language classes. As a result, teachers claimed that they required further professional learning about Critical Thinking practices and related assessment tasks before they would be able to effectively facilitate students’ Critical Thinking. The need to overcome these barriers to effective Critical Thinking facilitation in English language classes provides a rationale for including observations of teacher and student practices in classrooms, as well as policy.Ricky Fernandes, John Willison, Christopher Boyle and Desiani Muliasar
Sustainable and cost-effective microgrid sizing methodology for mining operations considering reliability and energy not-served
No full textMining industries consume a significant amounts of energy from fossil fuels, increasing carbon emissions. This paper presents a framework for the design of sustainable microgrid systems for mining through the integration of renewable energy sources to maximise environmental and economic outcomes. The study evaluates the applicability of solar PV, wind turbines, battery storage and diesel generators through a cost-benefit analysis in terms of energy cost, emissions, and reliability. Key findings indicate that wind turbines, when combined with diesel generators, drastically reduce cost and emissions. This work also examines microgrid configurations that have a lower diesel generator capacity but offer near-perfect reliability. Such configurations have proven to be feasible, as the energy shortfall is minimal and manageable by existing mining resources, thus reducing both costs and emissions.Shah Mohammad Mominul Islam, Hossein Ranjbar, S. Ali Pourmousavi, Wen L. Soon
Indigenous Peoples and the Future of Federalism
No full textBook reviewIn this study, a novel method for lead (Pb) immobilization was developed in contaminated soils using iron (III) (Fe3+) in conjunction with 0.05 M H2SO4. During method optimization, a range of microwave treatment times, solid to solution ratios, and Fe2(SO4)3/H2SO4 concentrations were assessed using a mining/smelting impacted soil (BHK2, Pb: 3031 mg/kg), followed by treatment of additional Pb contaminated soils (PP, Pb: 1506 mg/kg, G10, Pb: 2454 mg/kg and SoFC-1, Pb: 6340 mg/kg) using the optimized method. Pb bioaccessibility was assessed using USEPA Method 1340, with Pb speciation determined by X-ray Absorption (XAS) spectroscopy. Treatment efficacy was also validated using an in vivo mouse assay, where Pb accumulation in femur, kidney and liver was assessed to confirm in vitro bioaccessibility outcomes. Results showed that Pb bioaccessibility could be reduced by 77.4 - 97.0% following treatment of soil with Fe2(SO4)3 (0.4 - 1.0 M), H2SO4 (0.05 M) at 150°C for 60 min in a closed microwave system. Results of bioavailability assessment demonstrated treatment effect ratio of 0.06 - 0.07 in femur, 0.06 - 0.27 in kidney and 0.06 - 0.11 in liver (bioavailability reduction between 73-93%). Formation of plumbojarosite in treated soils was confirmed by XAS analysis.Madeleine Perret
The structure and dynamics of water molecule networks underlie catalytic efficiency in a glycoside exo-hydrolase
No full textData source: Supplementary material, https://doi.org/10.3389/fspor.2023.1235611Glycoside hydrolases break glycosidic bonds by transferring a water molecule onto the glycosidic oxygen of carbohydrates, but on the nanoscale, the dynamics of water molecules remains unclear.We investigate the role of the non-nucleophilic E220 glutamate, essential for maintaining the water molecule network in a family 3 β-D-glucan glucohydrolase, but not involved directly in catalysis. Kinetic data disclose that the E220A mutant retains substrate poly-specificity but has drastically reduced catalytic efficiency compared to the wild-type. High-resolution structures in-complex with a hydrolytic product and a mechanism-based inhibitor reveal that in wild-type, the concatenated water molecules near acid/base E491 and neighbouring N219 and E220 form a harmonised network. In contrast, in the E220A mutant, this network is uncoordinated. Computational models of covalent complexes show that water flux through the wild-type protein correlates with high catalytic efficiency dissimilar to E220A, where this correlation is lost. Ancestral sequence reconstructions of family 3 enzymes divulge the evolutionary conservation of residues participating in water molecule networks, which underlie substrate-product-assisted processivity. Our findings provide a blueprint for the dynamics of catalysis mediated by hydrolytic enzymes, which could inspire bioengineering to create a sustainable bioeconomy.Sukanya Luang, Xavier Fernández-Luengo, Victor A. Streltsov, Jean-Didier Maréchal, Laura Masgrau and Maria Hrmov