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Investigating Thrombosis in Mechanical Circulatory Support Devices
No full textMechanical circulatory support devices (MCS), such as extracorporeal membrane oxygenation (ECMO), assist perfusion in critically ill cardiorespiratory patients. Yet, thrombosis in such devices risks adverse events, including circuit occlusion and failure, and patient embolism. MCS thrombosis results from the interplay between haemodynamic conditions, biomaterial properties, and patient-specific pathologies; however, their interplay remains incompletely understood, and current in vitro thrombosis models often fail to integrate these factors under clinically relevant conditions.
This thesis developed a clinically guided microfluidic ECMO thrombosis-on-a-chip model that integrated customisable flow conditions, biomaterials, and healthy donor or patient blood samples, enabling high-throughput assessment of thrombosis mechanisms and screening the thrombogenicity of ECMO conditions. ECMO tubing-connector junctions, corresponding to flow gradients, were frequent sources of thrombosis in a retrospective observational study of patient circuits. The ECMO thrombosis-on-a-chip model mimicked this phenomenon, with platelet aggregate adhesion, growth, and embolism observed at flow gradients. Having validated the ability of the model to replicate clinical observations, further thrombotic effects elucidated by the model include that low shear rate and circuit stoppage increased platelet adhesion, polyvinyl chloride increased platelet activation compared to polycarbonate, polycarbonate and polyvinyl chloride increased platelet adhesion but decreased coagulation compared to polypropylene and polydimethylsiloxane, and ECMO patient blood samples showed less platelet adhesion compared to healthy donor samples.
Together, the novel medical device thrombosis-on-a-chip platform and its findings offer insights into thrombosis in ECMO and MCS, informing testing and design considerations for the next generation of MCS to reduce thrombotic and haemostatic complications in clinical practice
An ecological approach to the intensification of teachers’ work and its influence on their classroom practices, interactions, and relationships with students.
No full textFramed by Bronfenbrenner’s ecological systems theory (Bronfenbrenner & Ceci, 1994), this study examined how the multiple systems in which schools and teachers are embedded in (chrono, macro, exo, meso, and micro) shape teachers’ work, interactions, and practice. Positive teacher-student interactions are key to strong relationships, effective learning, and teacher and student wellbeing. Yet, as workloads grow and diversify, these relationships face increasing strain.
This study focused on three questions:
Q1. What teacher practices and teacher-student interactions are observed in secondary school classrooms?
Q2. What are the ecological contextual factors teachers perceive are influencing their work and how are they managing their work?
Q3. Drawing on both observation and teacher perceptions, what are the relationships between teacher-student interactions and relationships, teachers’ work demands, and classroom practices?
A semi-structured observation tool—adapted from a meta-analysis by Kincade, Cook & Goerdt (2020), captured teacher-student interactions, while follow-up interviews explored teachers’ perspectives. Secondary schools in NSW were purposively sampled ensuring representation across school sectors, geographic locations, and ICSEA scores.
The findings reveal that teachers' work is shaped by a complex ecological system, with pressures emerging from macro, exo and meso systems, often driven by rapid social, political, and technological change. These external forces filter into teachers’ everyday practice. Teachers report feeling time-poor and overstretched, pulled between supporting students, teaching, and administrative compliance. These layered demands are weakening teacher-student connections, and contribute to work intensification. It also affects teacher wellbeing, contributing to stress and burnout. Without acknowledging this ecological complexity, ongoing pressures will keep undermining teachers’ practice, wellbeing, and student outcomes
Understanding and measuring the wellbeing of Australian university students
No full textAustralian university student populations have increased substantially within the past two decades. Troublingly, these large university student populations appear to be experiencing poor and declining rates of wellbeing. Recognition of poor wellbeing among university students has galvanised calls for universities to better support student wellbeing. Developing effective wellbeing policies requires robustly understanding the factors that underlie university student wellbeing. Evaluating the effectiveness of such policies requires validly measuring the wellbeing of large university populations. This thesis presents five interrelated studies which seek to elevate the understanding and measurement of Australian university student wellbeing.
This research represents an important contribution towards expanding the empirical evidence base into university student wellbeing. Of particular note, this thesis enhances understandings of how university experiences shape student wellbeing. This is an encouraging finding as it suggests that directly addressing features of university life may be an effective and under- utilised approach for supporting student wellbeing. This thesis also provides important and novel insights into potential methods for improving the measurement of university student wellbeing
The Next Generation of Anonymous Credentials and Zero-Knowledge Proofs of Knowledge for Private Digital Identity
No full textDigital credential wallets manage identity documents such as government IDs and financial certificates, face the trilemma of privacy, security, and usability. Optimizing for anonymity by using Anonymous Credentials enhances privacy, but introduces challenges. Current benchmarks show verification using zero-knowledge proofs of knowledge taking 50–500ms, far exceeding the <1ms of standard credentials, impeding usability. Additionally, anonymity complicates security: preventing multiple-credential issuance (sybil resistance) or enforcing revocation becomes difficult when both users and objects are essentially secret. These issues are urgent due to the EU’s 2026 mandate for EU-wide credential wallet usage, which will drive widespread adoption of digital credential wallets, while critical use cases, like privately combining credentials from multiple issuers for KYC, emphasize the importance of this work.
This thesis extends existing work and develops new, fast cryptographic primitives for privacy preserving credential wallets. It introduces the fastest anonymous credential scheme with a 3.77ms Show+Verify time for 10 attributes, outperforming prior methods by 10-15%. Three extensions enhance this scheme. 1) formalized Identity Binding property for secure multi-issuer, multi-credential verification, with an implementation verifying 16 credentials from unique issuers in 72ms; 2) new nullifier constructions using Σ-protocols without pairings, improving privacy-preserving sybil resistance by 5x over previous approaches; 3) T-SIRIS, a threshold-issued, sybil-resistant identity system with near-constant Show+Verify times, over 30x faster than comparable systems [RAR+24]. These advancements are validated by an open-source Rust benchmarking library, delivering standardized empirical data across anonymous credential schemes
Molecular probes for selective sensing of membrane phospholipids
No full textPhospholipids are major components of the biological membranes; tools for detecting them in living
cells and organisms are essential to understand the functions of different phospholipids. This thesis
focuses on the development and application of novel fluorescent molecular probes to selectively
detect phospholipids in membranes, aiming to provide new tools to study their dynamics and
functions in biological processes. A series of probes targeting phosphatidylserine and
phosphatidylcholine were synthesised and their binding evaluated using a range of techniques,
advancing our understanding of how to design selective fluorescent sensors for membrane
phospholipids
Mobile health pulmonary rehabilitation for people with chronic obstructive pulmonary disease
No full textChronic obstructive pulmonary disease (COPD) is one of the leading causes of disease burden and mortality worldwide. Pulmonary rehabilitation (PR) is strongly recommended as an essential intervention that improves exercise capacity and health-related quality of life in people with COPD. However, significant barriers to access, uptake and completion of the program persist, underscoring the vital need to explore alternative, effective models of PR. Mobile health (mHealth), presents a novel mode of delivering PR that could help overcome some barriers to PR. To date, no randomised controlled trial has rigorously evaluated an mHealth PR program that included all essential components of PR. Chapter 1 is a literature review that establishes the background for this thesis. The aims of the studies presented in Chapter 2, 3 and 4 were i) to determine if mHealth PR was equivalent to centre-based PR for improvements in exercise capacity and health status in people with COPD (Chapter 2); ii) to characterise the engagement behaviour and evaluate the adherence of people with COPD to the multiple components within an mHealth PR app (Chapter 3); and iii) to determine the resource usage costs and carbon footprint of delivering an mHealth PR program to people with COPD (Chapter 4). The main findings were: i) mHealth PR could be a clinically effective option for people with COPD with at least adequate technology skills but should contain all essential and desirable components of PR (Chapter 2); ii) people with COPD can engage and adhere highly to multiple components within an mHealth PR app (Chapter 3); and iii) mHealth PR programs could be implemented into clinical practice to optimise savings in resource usage costs and GHG emissions (Chapter 4). A summary of the main findings of this thesis and the limitations, clinical implications and suggestions for future research are discussed in Chapter 5
Performance of Byzantine Fault Tolerant Blockchains
No full textBlockchains have garnered significant attention, leading to a proliferation of systems available for adoption. However, choosing the right blockchain for a specific application remains challenging due to a lack of comparative analyses of core metrics such as throughput, latency, and scalability. While several studies have focused on performance evaluation, few address blockchains that are both efficient—avoiding complex Proof-of-Work cryptographic puzzles—and secure, achieving deterministic consensus despite Byzantine failures. This thesis evaluates the performance of three blockchains designed to handle such adversarial behaviors: Burrow, Quorum, and Red Belly Blockchain. For this purpose, we modified the Hyperledger Caliper benchmarking tool by addressing three key limitations: unnecessary overheads, online cryptographic signatures, and centralized clients. Our findings reveal the maximum send rate that Burrow and Quorum can sustain, and demonstrate that Red Belly Blockchain achieves up to 8 times higher throughput than the other blockchains
The Lived Experiences of Javanese Women in a Context of Rural Transformation
No full textRural women in Indonesia play a significant economic role, yet face persistent inequality rooted in
cultural norms. This inequality is reflected in Indonesia's high gender inequality index, ranking among
the highest in Southeast Asia, demonstrating how economic development alone has not transformed
entrenched gender inequities. While rural areas experience transformation, driving economic and
social changes, conservative gender norms continue to constrain women's ability to benefit from
development opportunities.
This thesis examines how rural transformation processes reshape gender dynamics in Central Java
through an ethnographic study of two villages in Wonogiri. Drawing on fieldwork with over 200
participants, this study reveals how rural transformation fundamentally reshapes gender roles
through changes in livelihood strategies and intensified rural-urban connections. Women's roles have expanded across multiple domains, granting unprecedented access to education, formal
employment, and leadership positions once predominantly held by men.
These changes occur within conservative social structures shaped by religious interpretations and
state ideology, creating a contradiction between women's contributions and how these roles are
socially perceived. This reveals a paradox: while women perceive expanded roles as liberation, they
also experience intensified workloads of productive labour, reproductive duties, and community
obligations.
The thesis argues that shifting gender roles represent strategic household adaptations, with women
serving as essential human capital in diversified livelihood portfolios. Women navigate changes by
reinterpreting traditional norms within established frameworks, legitimising expanded roles while
preserving social acceptance. Communities respond to economic shifts by reinterpreting norms from
within, demonstrating that while economic changes occur rapidly, social structures evolve
incrementally through strategic adaptation
Engaging diffractive ethnography to explore student and teacher perceptions of collaborative testing
No full textHigh-stakes testing is crucial for evaluating student, teacher, and school performance worldwide. However, Australia's senior secondary assessment system has been criticised for excessively emphasising discipline-based knowledge. It sidelines critical 21st-century skills such as critical thinking, communication, and collaboration, distorting teaching practices and limiting holistic student development. Advocates recommend a balanced approach that includes diverse assessments like teacher evaluations, external exams, online tests, and collaborative testing to capture students' capabilities better. Employing diffractive ethnography based on Karen Barad's agential realism, this research explores the complex dynamics of collaborative testing and how educational practices intertwine with material conditions. This approach reveals how these elements actively shape collaborative environments and contribute to the educational process, providing a nuanced understanding of how educational realities are continually recreated through intra-actions and emphasising the significant role of material conditions. Findings indicate that collaborative testing enhances student outcomes by promoting peer discussions and developing 21st-century skills, with effective implementation relying on positive interdependence, ample discussion time, and strategic grouping. External testing pressures expose significant systemic barriers, underlining the benefits and challenges of collaborative testing and its broader implications for educational assessments. This research validates the effectiveness of collaborative testing in high schools. It highlights ethnography's role in exploring complex educational phenomena, particularly the profound influence of the material environment on learning processes
“Moral Illumination”: On Martha C. Nussbaum’s Literary Ethics
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