85000 research outputs found
Sort by
Machine Learning(s) in gaming disorder through the user-avatar bond: A step towards conceptual and methodological clarity.
No full textIn response to our study, the commentary by Infanti et al. (2024) raised critical points regarding (i) the conceptualization and utility of the user-avatar bond in addressing gaming disorder (GD) risk, and (ii) the optimization of supervised machine learning techniques applied to assess GD risk. To advance the scientific dialogue and progress in these areas, the present paper aims to: (i) enhance the clarity and understanding of the concepts of the avatar, the user-avatar bond, and the digital phenotype concerning gaming disorder (GD) within the broader field of behavioral addictions, and (ii) comparatively assess how the user-avatar bond (UAB) may predict GD risk, by both removing data augmentation before the data split and by implementing alternative data imbalance treatment approaches in programming.</p
Essays on Downside Risk: Evidence from Board Diversity, CEO Traits, and Social Networks
No full textThis thesis emphasises the importance of downside risk, which refers to the potential for an experience of a loss in value or earnings, as a critical risk measure. It presents three essays that offer fresh perspectives on the relationships between corporate governance, social networks, and this type of risk, using comprehensive datasets of US-listed nonfinancial firms.
The first essay examines the impact of board diversity on corporate downside risk using a multidimensional conceptualisation of diversity that includes cognitive and demographic factors using 29,481 firm-year observations from 3,286 unique firms (2006-2022). The essay finds that overall board and task-oriented diversity are negatively associated with both market-related and earnings-related downside risk. Relation-oriented diversity shows less consistent effects. Disaggregated analysis reveals that higher proportions of female directors and finance experts on boards reduce market downside risk, while nationality mix is negatively related to earnings downside risk. Importantly, task-oriented diversity components, such as finance expertise, board experience, and education level, emerge as more impactful than relation-oriented components in mitigating downside risk. The findings highlight the importance of a sophisticated, context-specific approach to board diversity for effective risk management.
The second essay investigates the relationship between CEO gender, experience, power dynamics, and downside risk using 31,339 firm-year observations from 3,576 unique firms (2004-2022). Our findings support the conventional view that female CEOs are more risk-averse than their male counterparts, using the 2SLS model that addresses the concern of endogeneity. However, female CEOs’ role in reducing downside risk depends on the auditing firm type and diversity composition of the board. The risk-reducing benefits of female leadership are diminished when female CEOs hold certain types of power and experiences, potentially due to overconfidence bias and status concerns. The essay emphasises the importance of considering gender diversity, power distribution, and expertise among CEOs when assessing their impact on firm outcomes, particularly downside risk.
The third essay explores the relationship between CEOs’ social networks and downside risk using 25,917 firm-year observations from 3,150 unique firms (2006-2022). The essay focuses on the CEO social network-to-board social network ratio as an indicator of the size of CEOs’ social networks and considers various downside risk measures. The findings reveal that a more extensive CEO social network, which can be understood as a form of social capital, is associated with lower market downside risk and earnings downside risk, suggesting a potential positive role of CEO social capital in mitigating corporate risk. It also shows that the size of CEOs’ social networks contributes to mitigating the asymmetric information between the firms and the market by reducing stock price synchronisation, indirectly mitigating corporate downside risk. The study also examines how the hedging activities, CEO gender, and diversity in the boardroom affect the relationship between CEO networks and firm risk, contributing to a comprehensive understanding of how CEO social networks influence downside risk in corporations.
Several robustness analyses support the findings of this thesis. The findings of the thesis contribute significantly to corporate governance, social networks, and risk management literature. It offers novel insights into the complex relationships between board diversity, CEO characteristics, social networks, and downside risk. Importantly, the findings provide actionable insights for firms, enabling them to optimise their leadership structure and board composition to mitigate downside risk in their specific contexts effectively. The study also calls for reevaluating risk management tools to align with this refined understanding of risk, underlining the importance of a multidimensional approach to diversity, CEO characteristics, and social networks in developing risk mitigation strategies.</p
Factsheet 4: Socio-economic Differences Between Cultural Attenders and Creative Participants
No full textStudies on social inequality and cultural engagement have traditionally focused on forms
and genres of cultural consumption (such as attending live theatre, reading books or listening
to music). They have consistently found strong associations between practices and tastes
in cultural consumption and social class.
In this factsheet we analyse and compare the demographic profiles of two overlapping groups:
those who attend cultural events (and who may or may not creatively participate; 64% of the survey
population), and those who creatively participate (and who may or may not attend; 46% of the
survey population).</p
Zirconia-based Catalysts for Biomass Conversion
No full textThe detrimental impact of carbon dioxide emissions from fossil fuels on global warming, combined with the increasing global demand for energy due to population growth, has intensified the search for renewable, low-carbon energy alternatives. Biorefineries, which aims to convert biomass to energy and other valuable by-product, are a sustainable means of chemical manufacturing in which multiple bioenergy products (e.g. fuels, food, specialty chemicals) are generated from naturally occurring biomass feedstocks such as forestry and agricultural waste through the integration of clean processes. In this regard, the conversion of biomass-derived C6 sugars into 5-(hydroxymethyl)furfural (HMF)—a pivotal platform chemical used to produce fuel precursors, additives, and value-added chemicals—has garnered significant attention. However, the high production cost of HMF continues to impede its commercial viability. Therefore, the development of a heterogeneously catalysed process to efficiently convert glucose to HMF in aqueous media remains highly desirable. HMF is synthesised by the cascade conversion of glucose over Lewis and Brønsted acid sites to respectively initiate isomerisation of glucose and subsequent dehydration of reactively formed fructose to HMF. Zirconia is a promising catalyst for such reactions; however, the impact of acid properties of different zirconia phases in these transformations is poorly understood. In this thesis, we unravel the role of the zirconia crystalline phase in glucose isomerisation to fructose and subsequent dehydration to HMF. The Lewis acidic monoclinic phase of zirconia is revealed to preferentially facilitate glucose isomerisation, while the nanoparticulate tetragonal phase possesses Brønsted acid sites which favour fructose dehydration. The synergy of both zirconia phases facilitates HMF production in a cascade process, with both catalysts investigated as physical mixtures in batch and flow reactor configurations. Using a physical mixture of only 15 wt% m-ZrO2 with 85 wt% t-ZrO2 in either batch or packed bed reactor configuration is sufficient to reach equilibrium conversion of glucose for subsequent dehydration by the t-ZrO2 component. Under continuous flow, a six-fold increase in HMF production was obtained when operating with a physical mixture of m- and t-ZrO2 compared to that from a single bed of t-ZrO2.
Further improvement in catalytic performance has been achieved using bifunctional catalysts through the synthesis of surface sulphation on calcined zirconium hydroxide, monoclinic and tetragonal zirconia. Sulfated zirconia (SZ) is produced via surface sulfation on calcined zirconium hydroxide, where monolayers of sulfate groups are formed from sulfuric acid. Analysis indicates that sub-monolayer SO4 coverages provide an optimal balance of Lewis and Brønsted acid sites, which are essential for the two-step cascade conversion of glucose to HMF. However, the influence of the zirconia crystalline phase on surface sulphation remains poorly understood. We then demonstrate a systematic control on Lewis-Brønsted acid properties of sulfated monoclinic (SZ(m)) and tetragonal zirconia (SZ(t)). Results show that surface sulfation enhances both Lewis and Brønsted acidity in SZ(m), leading to constant catalytic activity for glucose isomerisation to fructose—the rate-determining step in the cascade glucose conversion to HMF, even at high concentration sulfate coverage. While non-acidic sulfate species were formed in SZ(t) when surface S content exceeds 2.0 wt%. Additionally, SZ(m) catalysts demonstrate remarkable stability under continuous flow conditions at 150 °C for 6 h, with optimal activity observed in samples treated with 0.01 M H2SO4.
The valorisation of biomass-derived citral is an important application in sustainable chemical manufacturing. Citral can undergo catalytic transfer hydrogenation to produce geraniol and nerol, both of which are valuable compounds used predominantly in the fragrance industry. Zirconia, particularly when calcined from Zr(OH)4 at 400 °C, has demonstrated high activity in the selective hydrogenation of the C=O bond in citral, achieving nearly 100% selectivity toward the desired products in both batch and flow conditions. Weak Lewis acid sites on the zirconia surface have been identified as the active sites responsible for this reaction. Additionally, citral can be converted to p-cymene through a cyclodehydration pathway using SZ catalysts. This cascade reaction requires a specific surface sulfur content, with 1.6 wt% sulfur necessary to initiate the process. Complete conversion of citral occurs when the surface sulfur content exceeds 2.9 wt%.</p
Finitely Related Semigroups and Associated Structures
No full textAn algebra A is said to be finitely related (or has finite degree) if there exists a finite set of finitary relations such that the operations preserving those relations are precisely the term functions of A. Determining when a finite algebra is finitely related is called the finite degree problem. While the finite degree problem for algebras in general is well studied, it is far less developed for semigroups and other semigroup-like structures. In this thesis we will give a partial answer to the finite degree problem for permutative semigroups. We will show that there are large classes of non-finitely related nilpotent monoids and use them to study the preservation and non-preservation of finite relatedness. In the final chapter, we begin the study of the finite degree problem for additively idempotent semirings and pointed semidiscriminator extensions. Here, a tool from the theory of natural dualities will be developed and a link between the finite dualisability of an algebra and the finite relatedness of its pointed semidiscriminator extensions will be established.</p
Tending the Edges: An Exploration of Systemic Thinking Principles in Co-design for Healthcare
No full textThrough this research, I explored the application of systemic thinking principles to the fuzzy front end of co-design in healthcare.
Both systems thinking and co-design promise to include people in the design process. My approach to co-design aligns with the understanding of co-design as an ongoing partnership with all participants. Combining co-design, ethnography, and hanging out, I applied systemic thinking principles to the development of generative co-design tools. My practice is also informed by my background in permaculture, ethnography and sustainable design.
This research was undertaken through a series of projects embedded in healthcare organisations. Using systemic thinking principles was valuable in surfacing rich insights into patient and staff experiences. However, I also encountered many challenges with using systems and systemic thinking.
Through reflection, I found the systemic thinking principles began to merge and blur together, and I learned how the metaphors in a systems-informed design practice can be in tension with our intentions. As a result, my practice has changed to become attentive and responsive to a context aligned with living systems as a paradigm.</p
Japan’s Artificial Intelligence Strategy The challenge for AI collaboration across the Trilateral Security Dialogue (TSD)
No full textThe Australia-United Kingdom-United States AUKUS) agreement on strategic technology sharing has triggered a broader discussion on the necessity and ability for like-minded states to engage in deeper trade, military, intelligence, and information sharing for national growth and development, and also regional security. This report, like others in this series, highlights the Trilateral Security Dialogue (TSD) as an important platform to enable this agenda. Japan’s technological capabilities, strategic alignment, regional security concerns, and shared values make it a natural partner for Australia and the US in defence technology, particularly in the field of AI. There is also strong enthusiasm within the Japanese government and broader AI expert community to move beyond current project based defence cooperation agreements to bridging priority capability development with collaborative partnerships. Recent AI strategy documents highlight an encouraging alignment in this regard.
In this report, the authors highlight the potential for AI defence cooperation with Japan and the role the Defence Trade Cooperation Treaties (DTCT) can play in improving AI collaboration, particularly in dual-use domains. It brings to the fore the influence of uniquely Japanese cultural elements on civil-military cooperation and the need for cybersecurity assurances following recent high profile cyber intrusions within the Japanese Ministry of Defense. The benefits of sandboxing exercises that consider Japan’s particular regulatory landscape are also discussed, along with the importance of establishing focal points in each country to navigate government bureaucracy. The report also emphasises the importance of interaction between governments and public service, industry, and academia from Australia, Japan, and the US, discussing the potential benefits of such interaction, including overcoming linguistic issues in AI and harmonising ethical frameworks and terminology
Physico-chemical characterisation of glycerol- and ethylene glycol-based deep eutectic solvents
No full textDeep eutectic solvents are of significant interest to numerous applications including cryopreservation, chemical synthesis, lubrication, energy storage, catalysis, and self-assembly. However, to date there have been few rigorous and systematic studies of the physico-chemical and thermal properties of these solvents. This means that conclusive structure-function relationships are difficult to define within the context of the current literature. Here, we present the viscosity, refractive index, density, surface tension, and thermal behaviour of mixtures of either glycerol or ethylene glycol with choline chloride, betaine, or L-proline, as neat fluids and in the presence of water. We demonstrate that changing the ratio of hydrogen bond donor to hydrogen bond acceptor has only a small effect on the physico-chemical properties, while the addition of even small quantities of water has a significant effect. Despite rigorous studies, we demonstrate that determining the eutectic point of these mixtures is not straight-forward and that the definition of a ‘deep’ eutectic solvent may need to be reviewed in the frame of ideal mixing theory.</p
Potential candidates from a functional food Zanthoxyli Pericarpium (Sichuan pepper) for the management of hyperuricemia: high-through virtual screening, network pharmacology and dynamics simulations
No full textIntroduction: Hyperuricemia (HUA) is a metabolic syndrome caused by purine metabolism disorders. Zanthoxyli Pericarpium (ZP) is a medicinal and food homologous plant, and its ripe peel is used to treat diseases and as a spice for cooking. Some studies have shown that ZP can inhibit the formation of xanthine oxidase and reduce the production of uric acid.
Methods: Through network pharmacology, ZP’s potential targets and mechanisms for HUA treatment were identified. Databases like TCMSP, UniProt, and Swiss Target Prediction were utilized for ZP’s active ingredients and targets. HUA-related targets were filtered using GeneCards, Drugbank, and Open Targets. Core targets for ZP’s HUA treatment were mapped in a PPI network and analyzed with Cytoscape. GO and KEGG pathway enrichments were conducted on intersected targets via DAVID. Molecular docking and virtual screening were performed to find optimal binding pockets, and ADMET screening assessed compound safety. Molecular dynamics simulations confirmed compound stability in binding sites.
Results: We identified 81 ZP active ingredient targets, 140 HUA-related targets, and 6 drug targets, with xanthine dehydrogenase (XDH) as the top core target. Molecular docking revealed ZP’s active ingredients had strong binding to XDH. Virtual screening via Protein plus identified 48 compounds near the optimal binding pocket, with 2’-methylacetophenone, ledol, beta-sitosterol, and ethyl geranate as the most promising. Molecular dynamics simulations confirmed binding stability, suggesting ZP’s potential in HUA prevention and the need for further experimental validation.
Conclusion: Our study provides foundations for exploring the mechanism of the lowering of uric acid by ZP and developing new products of ZP. The role of ZP in the diet may provide a new dietary strategy for the prevention of HUA, and more experimental studies are needed to confirm our results in the future.</p
A Mobility of Sound Design Exploring a Listener Centred Approach to the Design of Sound
No full textAs a creative practice, the prominence of Sound Design lies in its connection to audio signal technologies, methods and techniques that facilitate the production of sonic narratives, sound effects and aural worlds. Yet, the contexts in which sound design finds itself is expanding. No longer limited to the design of social narratives within the world of film, digital media or the performing arts, the practice exhibits an innate mobility that enables a traversing of disciplinary domains. While a traversing of disciplinary domains affords freedom for a practitioner to explore perceptual, technological, and environmental relations of sound, it presents a methodological challenge for the field. A tension begins to emerge when moving beyond a narrative design paradigm and this leads to the question: what connects an expanded practice of sound thinking and making to research in urban sound, auditory display design and sound art? This practice-led research explores a trajectory in my practice that is moving beyond the design of socio-political, sonic narratives. This research presents an orientation for thinking and making that is guided by a listener centred approach that incorporates an artistic presence in media production, and a design presence creating tools to support scientific research. In this research, sound is viewed as a spatio-temporal medium for exploring a dynamic relation between listener, sound and site. Building on my expertise as a sound practitioner, digital tool maker and artist, these skills come together through four projects, Urban Conversations, Urban Transformations, Beyond Data and Celestial Resonance. Using these projects as case-studies, this research explores a process of sound thinking and making through an examination of project contexts, including pragmatic and artistic intentions, methods and techniques. By critically engaging with the process of designing, and the concepts and ideas that emerge through making, the intent is to propose a conceptual model for sound designers working beyond a tradition of narrative design paradigm. This conceptual model brings together the key drivers of a listener centred approach and a toolbox of methods a practitioner may apply in the staging of design activities for realising a design artefact.</p