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A Multidisciplinary Assessment of Pharmaceuticals in Wastewaters: A Comparative Study of Oman and South Australia
No full textThe escalation of human activities, particularly the proliferation of pharmaceutical traces in waterways, poses a substantial threat to the environment and human well-being. This issue has become a global concern due to the widespread impact of pollution resulting from heightened pharmaceutical production and usage. Despite the gravity of the situation, environmental laws, regulations, and policies on pharmaceutical control are yet to attain a comprehensive global maturity. The incongruity between the surge in pharmaceutical production and the nascent state of regulatory frameworks is a cause for significant concern. The current state of global environmental legislation, regulatory mechanisms, and policy frameworks emphasizes their inadequacy in addressing the burgeoning challenges posed by pharmaceutical contamination.In this research project, an examination was conducted on pharmaceutical contamination of influent, and effluent wastewater samples from two countries that employ different wastewater treatment methodologies. Additionally, sludge samples from Oman were included to assess radiopharmaceutical contamination. These samples, known for their wide reusage and rich history in pollution research, were analysed to survey the extent of pharmaceutical contamination. Then, field studies focused on regions in Oman and South Australia, and reporter genes bioassays were employed to quantify responses precisely elicited by biologically active chemicals present in the samples. Furthermore, antibiotics' impacts on environmental aquatic organisms, particularly the non-targeted duckweed species, Lemna minor (L. minor), were examined.In Chapter 3, influent, effluent, and sludge samples were obtained from eight wastewater treatment plants (WWTPs) in Oman, quantifying nineteen pharmaceuticals and four radiopharmaceuticals in influent, effluent, and sludge samples. Sixty-nine percent of pharmaceuticals were partially or fully removed, while thirty-one percent showed higher effluent concentrations, suggesting accumulation after treatment. Most compounds detected as prominent pharmaceutical constituents were identical in diverse wastewater samples, with variations in concentrations. In Chapter 4, wastewater samples from 10 WWTPs in Oman and 2 WWTPs in South Australia were exposed on a panel of mammalian cell lines using CALUX® (Chemically Activated LUciferase eXpression) assays and epithelial fish cell line. Significant ROS levels and glucocorticoid receptor (GR) activity accumulated in cell lines exposed to wastewater from certain WWTPs in Oman, while notable ERα activity (0.045-0.073 ng/L E2 equivalent) was found at specific sites in Oman and South Australia. In Chapter 5, three antibiotics that are commonly found in the environment and in wastewater effluents—Ciprofloxacin (CIP), Erythromycin (ERY), and Sulfamethoxazole (SMX)— were studied to investigate their impact on the growth and physiological variables of the higher-order aquatic plant L. minor over 3 subsequent generations. Significant antibiotic effects on frond number, frond and root areas were found across generations and treatment days. The study underscores the urgent need for more robust and coordinated efforts to improve wastewater treatment and to safeguard the environment and human civilization from the adverse consequences of pharmaceutical contamination in the present and future scenarios.</p
Legacy Datasets and Their Impacts: Analysing Ecoinvent’s Influence on Wool and Polyester LCA Outcomes
No full textAccurate and transparent Life Cycle Assessment (LCA) datasets are essential for reliable sustainability evaluations, particularly in the complex and varied textile industry. Historically, the ecoinvent database has been a foundational source for LCA studies in the textile sector. This paper critically examines the limitations of the ecoinvent v3.7 dataset, which is widely used in academic research, industry tools, and policymaking. While newer versions, such as v3.11, released in 2024, have addressed many issues, including enhanced geographical representation and updated emission profiles for chemicals, this study emphasises the historical implications of earlier data versions. By comparing the cradle-to-gate Global Warming Potential (GWP) of wool and polyester jumpers, this research reveals how aggregated and outdated data underestimated the polyester’s environmental impact while overestimating that of wool. These discrepancies have shaped fibre certification, eco-labelling, and consumer perceptions for years. Understanding the legacy of these datasets is vital for re-evaluating past LCA-based decisions and guiding future assessments toward greater regional relevance and transparency.</p
Remolding Microenvironmental Homeostasis for Enhancing Regenerative Hypertrophic Scar Treatment Based on Functionalized Microneedles
No full textHypertrophic scar (HS) is a common pathological fibrous hyperplasia with high incidence and recurrence rates. The limited understanding of the pathological characteristics of HS restricts the therapeutic efficacy of current strategies. In this study, we first identified the elevated mitophagy and suppressed apoptosis in hypertrophic scar fibroblasts (HSFs), which combined with excess inflammation to constitute the pathological microenvironment of HS, driving us to develop a functionalized microneedle (MN) patch for inhibiting mitophagy, promoting apoptosis and modulating inflammation to adapt HS treatment. The MNs integrate curcumin‐loaded HSFs‐derived extracellular vesicles (Cur@EV) and a decellularized extracellular matrix from umbilical cord‐derived mesenchymal stem cells (UC‐MSCs‐dECM, UdECM). The homologous Cur@EV with enhanced cellular uptake significantly induced HSFs apoptosis via mitophagy inhibition, meanwhile reducing collagen deposition. Meanwhile, the UdECM exerted immunomodulation capacity by facilitating the M2 polarization of macrophages, aiding in the suppression of HSFs. Notably, the Cur@EV/UdECM‐functionalized MN patches exhibited regenerative therapeutic outcomes on a rabbit HS model, with HS inhibition and new hair follicle formation. Overall, this study presents a synergistic strategy based on the regulation of “mitophagy‐apoptosis‐inflammation,” offering a novel, minimally invasive approach for HS management. The integration of homologous Cur@EV and UdECM into an MN patch represents an innovative, multifunctional approach that combines mitophagy inhibition, apoptosis induction, and immunomodulation. The regenerative outcomes observed in the rabbit HS model, including hair follicle formation, further underscore the translational potential of this strategy. Future research will focus on optimizing patch design for scalable production, assessing long‐term safety and efficacy, and exploring its broader applicability.</p
Quantitative Prediction of Incomplete Mixing in Transient Poroelastic Flows
No full textTransient flows in poroelastic media emerge in a wide array of contexts, spanning geophysical, biophysical, and industrial applications. Recent investigations reveal that even relatively simple poroelastic systems can exhibit Lagrangian chaos at the Darcy scale. The interplay of medium heterogeneity, poroelasticity and transient forcing leads to complex flow and transport behaviours that manifest as a diverse set of Lagrangian coherent structures (LCSs). The primary objective of this research is to elucidate how these diverse LCSs shape the transport and mixing of diffusive solutes.A minimal two-dimensional, sinusoidally forced poroelastic computational model was employed, accompanied by the development of several numerical methods to simulate diffusive particles and construct continuous concentration fields. LCSs were categorised into regular regions, KAM islands, stochastic layers, and other distinct types, and their impacts on solute transport and mixing were systematically examined across a broad range of Péclet numbers. Additionally, specialised metrics were introduced to quantify the interactions between diffusing solute blobs and the LCSs, both from local and global perspectives.It was found that LCS interactions impact the dispersion of solute plumes via the establishment of minimum flux manifolds, leading to strongly anomalous plume moments and solute residence time distributions. We interpret these results with fluid element stretching distributions and local Lyapunov exponents. Anomalous features persist even at low Péclet numbers. On the other hand, LCSs impart distinctly different mixing dynamics, with mixing metrics such as the dilution index ranging from algebraic to exponential growth with time. Transport structures such as KAM boundaries and hyperbolic manifolds form strong barriers that govern transport of diffusive solutes at all Péclet numbers.The results in this thesis show that diffusive solute mixing and transport are profoundly impacted by the complex advective dynamics inherent to transient poroelastic flows and can only be fully understood by resolving the governing LCSs.</p
Reservoir Computing in Lithium Niobate on Insulator Platforms
No full textThis work concerns time-delay reservoir computing (TDRC) in integrated photonic platforms, specifically the Lithium Niobate on Insulator (LNOI) platform. We propose a novel all-optical integrated architecture, which has only one tunable parameter in the form of a phase-shifter, and which can achieve good performance on several reservoir computing benchmark tasks. We also investigate the design space of this architecture and the asynchronous operation, which represents a departure from the more common framework of envisioning time-delay reservoir computers as networks in the stricter sense. Additionally, we propose to leverage the optical feedback to dispense with the input mask, which allows the bypassing of an O/E/O conversion, which is often necessary to apply the mask. In future work, this can allow the processing of real-time incoming signals, possibly for telecom/edge applications. The effects of the output electronic readout on the proposed architecture's performance are also investigated. Initial experimental work is also reported. The unifying theme of this work is to investigate the performance possibilities with minimum photonic hardware requirements, relying mainly on LNOI’s low losses which enables the integration of the feedback waveguide, and using only interference and subsequent intensity conversion (through a photodetector) as the nonlinearity. This provides a base for future work to compare against in terms of performance gains when additional nonlinearities are considered (such as those available on the LNOI platform), and when overall system complexity is increased by means of introducing more tunable parameters. Thus, the scope of this work is about the exploration of one particular unconventional computing approach (reservoir computing), using one particular technology (photonics), on one particular platform (lithium niobate on insulator). This work builds on the increasing interest of exploring unconventional computing, since it has been shown over the years that digital computers can no longer be a `one-size-fits-all', especially for emerging applications like artificial intelligence (AI). The future landscape of computing will likely encompass a rich variety of computing paradigms, architectures, and hardware, to meet the needs of rising specialized applications, and all in coexistence with digital computers which remain, at least for now, better suited for general-purpose computing.</p
Defining the Role of Adipokines in the Development of Chronic Obstructive Pulmonary Disease and the Related Metabolic Comorbidities
No full textChronic obstructive pulmonary disease (COPD) is the third leading cause of death globally. Cigarette smoking is the primary risk factor, accounting for over 95% of cases in industrialized countries, including Australia. COPD is a chronic, irreversible disease with systemic effects, leading to comorbidities such as cardiovascular disease, skeletal muscle wasting, and metabolic disorders, which significantly impact hospitalization rates, mortality, and quality of life.Adipose tissue, once considered merely an energy storage depot, is now recognized as a critical endocrine organ involved in energy metabolism and inflammation. Adipose tissue secretes adipokines that regulate homeostasis in healthy states and contribute to pathophysiology in diseases such as COPD. Clinical evidence shows adipose dysfunction and adipokine dysregulation in COPD patients, though the mechanisms underlying this relationship remain unclear. This thesis investigates adipose tissue function and adipokine regulation under cigarette smoking conditions and explores the role of adipokines in COPD and related comorbidities.Cigarette smoke (CS) contains numerous toxic chemicals that induce oxidative stress and inflammation in the lungs, with potential effects on other organs such as the cardiovascular system, skeletal muscle, and adipose tissue. Previous studies have shown that CS induces insulin resistance, adipose dysfunction, and body weight loss by increasing lipolysis and energy expenditure in mice. However, the interaction between COPD and adipose dysfunction is not fully understood. Therefore, this thesis explores the impact of CS on adipose tissue and adipokine regulation in COPD.The first aim of this thesis was to examine the effects of CS exposure on adipose tissue function and metabolic parameters in a pre-clinical model of COPD. The hypothesis was that CS exposure disrupts metabolic parameters and adipokine production within adipose tissue. Results showed that CS exposure caused significant lung inflammation, with increased total cells and neutrophils, as well as oxidative stress in both lung and adipose tissues. Smoking also led to body weight loss, glucose intolerance, and metabolic disturbances. Adipokine expression was dysregulated in both 2-month and 6-month smoking groups, and elevated levels of non-esterified fatty acids (NEFA) and triglycerides (TG) were observed in serum. Lipolysis-related proteins were also upregulated in adipose tissue under smoking conditions, indicating adipose dysfunction.The second aim was to investigate the role of oxidative stress in adipose dysfunction and metabolic disturbances in COPD. Using the antioxidant apocynin, smoking-induced lung inflammation and oxidative stress were significantly reduced. However, apocynin treatment did not restore body weight or metabolism. Oxidative stress inhibition also reduced lipolysis, with decreased expression of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) in adipose tissue and reduced NEFA and TG levels in serum. Additionally, oxidative stress reduction improved insulin sensitivity in adipose tissue and alleviated glucose intolerance.The third aim was to identify adipokine-associated signalling pathways in lung tissue using a phospho-proteomics array. Analysis revealed that CS exposure activated several proteins in lung tissues compared to controls. Apelin, which was consistently altered in smoking-exposed adipose tissues, was identified as a key player in COPD progression. KEGG analysis indicated that the Apelin-related signalling pathway, involving the phosphorylation of AKT1 and RAF1, was activated in COPD. Additionally, apocynin treatment modulated phosphoproteins related to energy regulation and transcription factors, and Tnfα was implicated in COPD through alterations in MAPK1 and RPS6KA5 phosphorylation. These findings suggest the activation of signalling pathways like MAPK in COPD progression.The fourth aim was to explore the interaction between adipocytes and lung epithelial cells in COPD. This was studied by treating differentiated 3T3-L1 cells with conditioned media (CM) from cigarette smoke extract (CSE)-treated lung cells. CM_CSE treatment led to significant alterations in adipokine expression, particularly Apelin, Adiponectin, and Leptin, indicating that lung epithelial cells influence adipocyte function through secreted factors. In contrast, direct exposure to CSE had minimal effect on adipokine dysregulation. Inflammatory markers, such as Tnfα and IL-6, were upregulated in CM_CSE-treated adipocytes, while only Tnfα increased in direct CSE-treated cells. CM_CSE treatment also impaired mitochondrial biogenesis markers and promoted lipolysis in adipocytes, with increased expression of HSL and ATGL, suggesting a pathological interaction between lung epithelial cells and adipocytes in COPD.The final aim investigated the impact of adipocyte-released factors on lung cells. Factors secreted from adipocytes triggered oxidative stress in lung cells, leading to increased inflammation and apoptosis-related gene expression. Protein analysis showed increased levels of 19S, 20S, and HSP70, indicating a link between adipocyte-derived factors and lung cell dysfunction.In conclusion, this thesis provides evidence for active communication between lung and adipose tissue in COPD. The findings suggest that adipokine dysregulation and oxidative stress play pivotal roles in the development of COPD and its comorbidities, including metabolic disturbances and systemic inflammation. By elucidating the lung-adipose tissue axis, this study contributes to a deeper understanding of COPD pathophysiology and offers potential therapeutic avenues targeting both local and systemic aspects of the disease.</p
Nanocolloidal Chemistry in Liquid Metal Media
No full textLiquid metals (LMs) combine metallic conductivity with fluidic behaviour, enabling solvation and reactivity unattainable in conventional solvents. Yet, the atomic-scale chemistry governing solvation, dissolution, and crystallisation in these systems remains poorly understood. This thesis develops experimental and analytical methods to directly observe these processes in Ga-based LM alloys. A high-temperature sonication method using molten sodium acetate (NaOAc) was devised to synthesise homogeneous Ga-alloy nanodroplets. This approach enables controlled formation of transition-metal colloids (Cu, Ag, Au, Pd, Bi, Zn) suspended in Ga with tunable composition and nanometric droplet size. The resulting nanodroplets with solid intermetallic cores encapsulated by liquid Ga provide a platform for real-time studies of dissolution and crystallisation. In-situ transmission electron microscopy (TEM) revealed sequential dissolution and re-precipitation of intermetallic phases (e.g., CuGa₂) in the Cu–Ga system, confirming nanoscale solvation consistent with bulk phase diagrams. A key discovery made in this work is surface liquefaction, wherein the intermetallic–liquid interface for different alloys spontaneously forms a semi-liquid layer. For Cu-Ga specifically, surface liquefaction was exaggerated and demonstrated that several nanometres at room temperature fluctuated between a solid and liquid state. Molecular dynamics (MD) simulations attribute this to facet-specific atomic binding differences that induce localised melting, enhancing solubility and diffusivity. Size-dependent thermal behaviour, including suppressed melting points occur due to temperature depreciation induced by size effects. However, competing Laplacian pressures also stabilises the temperature variations, thereby affecting solubility effects. Extending to solubility–temperature relationships, a few systems were looked at i.e., Cu–Ga, Ag–Ga, Au–Ga, and Pd–Ga systems including a multicomponent liquid metal alloy (MCLMA). Ag₇Ga₃ from the MCLMA demonstrated segregation, whereas Au, Pd, and Cu shared a crystal structure.
The combination of in-situ TEM, and simulations established a unified framework for diffusion and crystallisation in LM solvation. This work introduced a transferable methodology and provides a foundation for characterising LM systems.</p
Drawing with The World Drawing Itself
No full textThis research experiments with drawing approaches I have explored in my art and my architecture over twenty-five years to further the possibilities of drawing as my central mode of research and practice. The research generates improvisational and interactive drawing approaches by working outside—with The World—through walking, movement, temporary mark-making, performative gestures, ephemeral actions, found and repurposed material and social histories and stories.My approaches enable me to extend and enact drawing at a one-to-one scale with The World—including weather, water, ground, infrastructures, and stories, drawing through, above and below ground. (Figure 2) These approaches lead my drawing practice beyond acts of mark-making to material, spatial and durational engagement that exposes interrelatedness between water, ground, settlement—and subsequent social and environmental effects—revealing Drawing with The World drawing itself as a catalyst for critical spatial, social, and environmental enquiry.Drawing with such conditions leads the research to the further proposition—designing with—moving the practice toward processes that are improvisational, lightweight, lowcost, and have low-embodied energy. These directions redirect my work as an architect from drawing and designing architecture, to drawing and designing with conditions that produce and subtend architecture from below, beside, above, around, and through.The title, ‘Drawing with The World drawing itself,’ references active and reciprocative processes that I create through the research and which are becoming strategies to move from drawings of the world, such as maps, surveys and plans—customary in architecture—to drawing and designing as part of a positive feedback loop between me and the environments where and when I draw and design.These directions, catalysed through drawing, are unfolding my art and architecture to one another and to associated disciplines, interior design, landscape architecture (through teaching, collaborating, exhibiting and writing), and to adjacent disciplines, such as environmental humanities, where drawing has capacity to trace and re-imagine connections between human, more than human and The World.</p
Beyond window shopping: Using stakeholder narratives to inform the design and impact of Australian non-metropolitan teacher placements
No full textDespite decades of policies and interventions, challenges in sustaining a consistent pipeline of teachers to meet the needs of Australian non-metropolitan areas remain unresolved. Legislative frameworks and policies emphasise that initial teacher education providers take steps to better prepare preservice teachers for these diverse contexts. In response, government-funded alliances have been established between universities and clusters of regional schools, aiming to deliver supported professional experience placements in such settings. To inform the future design of these initiatives, this study examines one university-school partnership situated in south-eastern Australia locality, classified as ‘regional’.
Using a figured worlds methodology, the study draws on the collective narratives of multiple stakeholders including teacher educators, mentor teachers, principals, and preservice teachers. Findings emphasise that to move beyond “window shopping” experiences, stakeholder agency must be central to any placement design. While funding and policy discussions emphasise investment in teacher education, the real challenge lies in aligning these efforts with the lived experiences of educators and communities in non-metropolitan areas. This study suggests that for long term impact, a more sustainable and community-driven approach is needed to address the realities of preparing teachers for these contexts.</p
Oxygen-mediated high uniform plasticity in α-β titanium alloys
No full textTitanium alloys are critically important materials, yet their development has long been constrained by a fundamental trade-off between yield strength and uniform elongation—a more challenging limitation than the conventional strength–ductility trade-off. Here, we present a dual strategy for α–β titanium alloys that transforms high oxygen from an embrittling liability into a powerful performance enabler. First, we leverage high oxygen ( ≥0.40%) to activate prominent pyramidal slip in the α-phase. Second, we engineer a tailored α–β microstructure through alloy design (Ti–O–Fe), laser-based powder bed fusion, and annealing to enable sustained slip transfer across α–β interfaces. The resulting high-strength α–β alloys achieve record uniform elongations: Ti-0.45O-4Fe delivers ≥14% (total: ≥27%) at yield strengths ≥980 MPa, and Ti-0.5O-5Fe achieves ≥13% (total: ≥23%) at yield strengths ≥1075 MPa. This work simultaneously addresses the yield strength–uniform elongation trade-off and oxygen embrittlement, demonstrating a design paradigm for α–β titanium alloys.</p