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Emulsion gels of oil encapsulated in double polysaccharide networks as animal fat analogues
No full textThe development of plant-based alternatives to replace animal products is crucial as the global population nears 10 billion by 2050, necessitating more sustainable food systems. Although efforts has been made in mimicking animal muscle textures using plant-based proteins, particularly the texturized plant proteins, the replication of animal fat properties remains challenging and less explored, particularly in light of recent commercial setbacks in the plant-based meat industry. Current study addressed this gap by investigating curdlan gum-konjac glucomannan (KGM)-pea protein emulsion gels as fat analogues, focusing on their stability and structure formation during cooking. We found that the use of a double polysaccharide network significantly enhanced the stability of emulsion gels, both before and after thermal processing, with controlled thermal history effectively guiding the gel morphology. Pea-protein-stabilised canola-oil emulsions (oil: 10–40 % w/w; protein: 5 % w/w) were blended with hydrated curdlan/KGM dispersions (total 4–7 %, w/w) and thermally set through a two-step heating regime (50 °C for 15 min, then 85 °C for 30 min) to form emulsion gels. Gels containing 6 % polysaccharide and 30 % oil exhibited only 57 ± 5 % oven shrinkage (pork fat = 63 ± 12 %), <15 % oil/water loss after five freeze-thaw cycles, and springness of 0.42 ± 0.05 (pork fat = 0.48 ± 0.06). Synchrotron-FTIR chemical imaging data confirmed the role of protein and polysaccharides in maintaining structural integrity, aligning with visual and rheological analyses. For the first time, we demonstrate that a sequentially gelled curdlan–KGM double network, reinforced by pea-protein interfaces, can lock sizable amounts of unsaturated oil into a cohesive matrix that reproduces the shrinkage, browning, and oil release of animal fat during cooking. This work therefore establishes a new, thermo-responsive route to plant-based fat analogues and offers mechanistic guidance for future meat-alternative formulations
Recovery of Radiation-induced Defects in Silicon Solar Cells: Enhanced Performance for Space Applications
No full textSPACE2.0 emphasises the development of smaller, versatile, and cost-effective satellites, crystalline silicon (c-Si) solar cells are attracting increasing interest in place of the III-V space solar cells. This shift is primarily due to the significant cost advantage of commercial silicon photovoltaic (PV) modules, which are around 0.1 USD/W compared to gallium arsenide (GaAs) PV modules at ~60 USD/W. However, the performance of silicon solar cells in space degrades significantly due to the irradiation by high-energy particles like electrons.
In this thesis, modern commercial silicon solar cells and wafers are exposed to electron radiation with doses up to 10^15 e/cm^2. The comparison of n-type tunnelling oxide passivated contact (TOPCon), p-TOPCon and p-type passivated emitter and rear contact (PERC) solar cells reveals that n-TOPCon solar cells are more sensitive to radiation damage, resulting in lower efficiencies after irradiation, while having higher efficiencies initially. It is also determined that the carrier effective lifetime in tested n-type wafers decreases by an order of magnitude for each order of magnitude increase in radiation dose. The formation of di-vacancies, other vacancy-related complexes and interstitial complexes are confirmed in both irradiated n-TOPCon and p-PERC solar cells.
Fortunately, bulk hydrogen is shown to significantly enhance the recovery of radiation-induced defects in p-PERC silicon solar cells. Hydrogenated samples show ~70 times faster recovery than hydrogen-lean samples at an accelerated recovery temperature of 380 °C. In addition, the effective bulk lifetime for the hydrogenated sample saturated at a value of 7 ms, compared to only 0.3 ms (both at Δn = 10^15 /cm^3) for the hydrogen lean sample. It should be noted that p-PERC solar cells already contain significant amounts of bulk hydrogen, which enables them to recover from the radiation-induced defects. As-fabricated n-TOPCon solar cells are relatively hydrogen-lean and do not show a considerable radiation-damage recovery ability.
The bulk hydrogen concentration in p-PERC and n-TOPCon solar cells is increased by using advanced hydrogenation techniques. In particular, it is shown for the first time that advanced-hydrogenated n-TOPCon solar cells exhibit rapid and complete recovery of radiation-induced defects, achieved within 30 hours at an accelerated recovery temperature of 150 °C and 1-sun equivalent illumination. Remarkably, the optimised advanced-hydrogenated n-TOPCon solar cells show a faster recovery speed and higher efficiency than p-PERC. Finally, it is shown that our advanced hydrogenation process benefits from lighter boron (B) emitter doping densities, which can be attributed to a more optimal hydrogen in-diffusion. These findings demonstrate that advanced-hydrogenated n-TOPCon solar cells could potentially be an appealing candidate for application in SPACE2.0
Numerical modelling of aerosol and CO2 transport for indoor air quality and infection risk assessment
No full textIndoor air quality and airborne transmission of infectious diseases are of critical concern in enclosed environments. While mitigation strategies for airborne disease transmission exist, they are often limited to specific settings; nonetheless, infectious diseases have continued to spread and evolve. This raises a key question: How can the effectiveness of ventilation and filtration be assessed across diverse indoor environments, given the limitations of the Wells-Riley model's well-mixed assumption and the need for real-time, particle size-resolved data? Therefore, this thesis addresses these limitations by developing a validated numerical framework that realistically simulates the transport of exhaled CO2 and aerosols under stale air, HEPA-filtered, and mechanically ventilated conditions. It also introduces a novel infection risk model that utilises aerosol measurements for real-time risk estimation and generates spatiotemporal maps of infection risk and safe occupancy time based on particle size distribution. This approach enables evaluation of ventilation and filtration effectiveness across diverse indoor settings.
A methodology is introduced to prescribe exhaled aerosol and CO2 boundary conditions for representing human breathing in CFD simulations. The approach is validated against in situ measurements obtained in a stale air classroom, ensuring realistic replication of occupant-generated emissions. Additionally, a radius-resolved infection risk model is developed with two approaches: (i) estimation of real-time infection risk using in situ aerosol measurements, and (ii) CFD-based mapping of spatiotemporal infection risk and safe occupancy time using exhaled aerosol size distributions.
Key findings from applying this novel infection risk model to a stale air classroom reveal considerable variation in occupancy time. For instance, in the case of a single infector scenario, the probability of infection can vary by more than 50%, depending on the location of the infected occupant within the room. Classrooms equipped with HEPA filtration that utilise three units significantly reduce aerosol concentrations while also redistributing particles unevenly due to differences in the filters’ clean air delivery rates, promoting a more uniform CO2 distribution. In contrast, a single HEPA unit achieves only minimal aerosol reduction, and its advantage in lowering concentrations is outweighed by the disadvantage of contaminant dispersion driven by its discharge airflow. This limitation is reflected in the infection risk maps, which show that under a single-infector scenario, almost none of the occupants remain safe after 25 minutes with one HEPA filter, compared with nearly 40% under stale air conditions. By comparison, the use of three HEPA units allows approximately 77% of occupants to remain safe within the same period. Nevertheless, elevated risks persist when the infector is positioned far from the filter intake, allowing wider dispersion of exhaled particles. Additionally, an aerosol removal model is developed to predict both the minimum aerosol concentration achievable with HEPA filtration and the time required to approach this value.
The dilution efficiency of CO2 concentration under mechanical ventilation in an aged care setting is found to vary with the architectural features of the room. While opening the bathroom door enhanced local dilution and extraction efficiency, particularly near the occupant, it also caused a slight increase in CO2 concentration at the room door, suggesting potential contaminant leakage to adjacent areas. This accumulation near the door is effectively mitigated by simultaneously opening the window and bathroom door.
This thesis makes a significant contribution by providing a realistic, predictive method for evaluating ventilation and filtration strategies in mitigating airborne infection risk. Its novelty lies in the development of a numerical model capable of realistically simulating the exhalation of aerosols and CO2 from occupants, as well as the integration of real-time aerosol measurements with an infection risk model, providing a practical tool for optimising indoor air quality interventions
Decolonising animal activism: engaging with Indigenous activist perspectives
No full textAnimal rights activism has been criticised in settler-colonial states for overlooking human rights abuses and shielding colonial powers. However, the efforts of animal rights activists to expand their political alliances with subaltern and colonised others are laden with tensions, stemming from the oppression and violence of settler-colonial projects. The steps that progressive non-Indigenous activists can take to support alliances with colonised others are therefore unclear. In this article, we contend that Indigenous activists' perspectives offer critical insights into the development of alliances between Indigenous and non-Indigenous activists towards linked human and animal rights in settler-colonial states. Drawing on an ethnography with Indigenous activists in Occupied Palestine (pre-October 7), we show that the conditions for alliance-building exceed the rejection of racialised settler colonialism. They also require commitments by non-Indigenous activists towards Indigenous grassroots movements encompassing the diverse political agendas and heterogeneity of Indigenous societies. Beyond the hegemony of Israeli occupation, Palestinian activists seek alliances that centre community and youth development, and self-determination as key dimensions of linked animal and human rights. These priorities unsettle the Western strictures of animal rights anchored in veganism as the sole political concern of Palestinian activists. Questioning the efficacy of inflexible moral and ethical frameworks as platforms for alliance-building, we instead locate alliances for linked animal and human rights within a politics of listening anchored in settler-colonial discomfort, the labour of yielding to Indigenous priorities and remaining open to contingent, ‘on the ground’ politics. In so doing, we show that activist ethnography can reveal complex postcolonial engagements with the political, and the plural and hybrid human and animal activisms that these geographies give rise to
Molten Salt-Promoted MgO-Based Sorbents for Intermediate-Temperature CO2 Capture: Performance Assessment for Post-Combustion Applications and Mechanistic Role of LiNO3
No full textClimate change mitigation requires effective CO2 capture technologies, with MgO-based sorbents emerging as promising candidates for intermediate-temperature (200-400 °C) applications due to their high theoretical capacity (24.8 mmol/g), thermal stability, and cost-effectiveness. While practical performance is severely limited by rapid formation of dense MgCO3 surface layer that blocks further CO2 diffusion, molten nitrate can prevent its formation and significantly enhance MgO’s carbonation.
This thesis systematically investigates molten salt-promoted MgO-based sorbents for CO2 capture using both fixed-bed reactor and thermogravimetric analysis, addressing critical performance gaps between laboratory and practical conditions. The fixed-bed experiments demonstrate the thermodynamic constraints of MgO/MgCO3 equilibrium at reduced CO2 partial pressures. Among the tested alkali metal salts, Na-salts exhibited the highest initial uptake, but poor stability compared to K-salts, while LiNO3 leads to significant performance fluctuations during cycling.
Herein, this study further investigates the individual effects of lithium nitrate (LiNO3) and its transformation product, lithium carbonate (Li2CO3), on MgO carbonation from both kinetic and thermodynamic aspects. Results show that Li+ (from LiNO3) inserts into MgO/MgCO3 lattices, slowing late-stage diffusion and elevating the MgO/MgCO3 equilibrium CO2 pressure. In contrast, Li2CO3 acts as a nucleation seed and stabilizer, outperforming LiNO3 by up to 159% at 0.2 atm CO2 and sustaining 33% MgO conversion after 20 cycles, 23% higher than Na2CO3-promoted analogues. Furthermore, mass-spectrometric tracking of NOx evolution demonstrates that MgCO3 drastically lowers LiNO3 thermostability, triggering denitration well below typical regeneration temperature (~400 °C), leading to our conclusion that LiNO3-rich sorbents cannot avoid gradual transformation to Li2CO3 during operation. Overall, the work reconciles conflicting literature by showing that Li2CO3 rather than LiNO3 drives performance gains. Therefore, we recommend substituting Li2CO3 for LiNO3 in molten salt modified MgO to achieve durable, high-capacity, and environmentally friendly sorbents
İnce İzler [in-jej eez-lehr] Delicate Traces: Geometry, Light, and the Art of Devotion
No full textİnce İzler (Delicate Traces) is a practice-based research project investigating geometry, materiality, and care through contemporary jewellery and decorative arts. The work integrates handcraft techniques (bead weaving, illumination, marbling) with modular and computational thinking to explore how cultural pattern systems, ecological fragility, and embodied making function as forms of knowledge production. The project contributes to research through design by positioning wearable artefacts as sites of inquiry into care, sustainability, and material culture
Precipitation and phase evolution in a Cu-modified near-α titanium alloy designed for additive manufacturing
No full textDeveloping lightweight high-temperature materials with excellent oxidation and creep resistance is crucial for improving efficiency in next-generation aerospace and energy systems. Near-α Ti alloys offer a promising balance of high specific strength, thermal stability, as well as oxidation resistance for such applications. However, exploiting their full potential, especially with additive manufacturing (AM), requires a deep understanding of their microstructural evolution under complex thermal conditions including phase transformations and precipitation pathways. Among various alloying strategies, Cu and Si additions show potential to promote grain refinement and enhance mechanical properties in Ti alloys processed by AM. However, the associated precipitation pathways, particularly those of Cu-rich intermetallics, remain largely unexplored in multicomponent near-α Ti systems. This study investigates phase transformations and precipitation behavior in a novel Cu- and Si-containing near-α Ti alloy using in situ high-energy X-ray diffraction (HEXRD) and small-angle X-ray scattering (SAXS), supported by transmission electron microscopy (TEM) and atom probe tomography (APT). Two intermetallic phases, Ti2Cu and S2-type (Ti,Zr)6Si3 silicides, are identified during continuous heating, each exhibiting distinct precipitation kinetics and thermal stability. SAXS reveals Ti2Cu precipitation already at ∼460 °C, indicating its potential formation at typical service temperatures (up to ∼600 °C). Quench rate experiments show that Ti2Cu precipitation can be suppressed at cooling rates above 50 °C/s, while forming between 620 and 500 °C at lower rates. These findings enable the design of heat treatments tailored for controlled precipitation and provide a foundation for future alloy development, contributing to improved efficiency and reliability of high-temperature components
Understanding Gender Differences in Injecting‐Related Harms Among an Australian Sample of People Who Inject Drugs
No full textINTRODUCTION: People who inject drugs may experience several non-viral injecting-related injuries and diseases (IRID), including skin and soft tissue infection (SSTI) and venous disease, often resulting from bacteria introduced via unsafe injecting practices or environments. Women are overrepresented among those reporting multiple and recent IRID. However, limited evidence exists about how gender interacts with known IRID risk factors.
METHODS: Surveys were conducted 2009-2023 with approximately 900 Australians who inject drugs per year (N = 7538 total). Participants self-reported past-month drug use behaviours and IRID experience. We conducted multivariable binary logistic regression to determine the relationship between gender and SSTI and venous disease. To examine whether gender uniquely affected specific injecting risk behaviours with respect to SSTI and venous disease, two interaction terms were separately added: (i) gender and injecting frequency; (ii) gender and reuse of one's needles.
RESULTS: Surveys were completed by 5038 men and 2500 women. Past-month SSTI was reported by 8% of the sample (95% confidence interval 7%-9%), with a higher proportion among women (10%) than men (7%). Overall, 4% reported past-month venous disease (95% confidence interval 3%-4%), a higher proportion among women (5%) than men (3%). Examining both outcomes, no statistically significant interactions between gender and needle reuse or injecting frequency were found.
DISCUSSION AND CONCLUSIONS: Despite no statistically significant interaction between gender and reuse or injecting frequency, our study demonstrates a gender difference in exposure to risk factors associated with SSTIs and venous disease. Interventions to reduce SSTI and venous disease, particularly those deemed safe and appropriate by women, are needed
Understanding How Chronic Pain Impacts Fall Risk and Mobility in Ageing
No full textBackground:
Chronic pain is highly prevalent and is a leading contributor to disability, reduced mobility, cognitive decline, and increased fall risk with ageing. Despite its widespread impact, the mechanisms linking chronic pain to these adverse outcomes in ageing remain poorly understood. Existing treatment models often adopt a reductionist approach, overlooking the complex interplay between behavioural, psychosocial, and neurological factors.
Aims and Objectives:
This thesis examined the multifaceted pathways through which chronic pain influences mobility impairment and falls with ageing. Specifically, it aimed to: (1) quantify the association between pain and gait function, (2) test an integrated model of pain-related fall risk using large-scale epidemiological data, (3) explore the lived experience of pain in later life, and (4) investigate neurobiological mechanisms using advanced brain imaging.
Methods:
A multi-method design was used across four interlinked studies. First, a systematic review and meta-analysis synthesised evidence on the relationship between chronic pain and gait in people aged 60 years and over. Second, structural equation modelling of UK Biobank data in people aged 40 years and over evaluated direct and indirect pathways from pain to falls, mediated by depression, inflammation, physical activity, gait quality, and cognition. Third, a qualitative study with people aged 60 years and over living with chronic pain explored the emotional, social, and functional impact of pain in ageing. Fourth, a neuroimaging study examined the associations between brain integrity and fall risk factors in people aged 50 and over living with chronic pain. Findings were integrated within a biopsychosocial-neurocognitive framework.
Results:
The meta-analysis confirmed a consistent association between chronic pain and slower walking speed, identifying walking speed as an early marker of mobility decline. The UK Biobank analysis demonstrated that pain increased fall risk through both direct and indirect pathways involving depression, inflammation, walking speed, and gait quality. Qualitative findings revealed a mismatch between the lived experience of people aged 60 years and over and current pain assessment practices, highlighting the need for more person-centred approaches. Neuroimaging results revealed significant associations between grey matter volume, white matter integrity, and tissue conductivity in regions critical for balance, motor control, and cognition, including the cerebellum, thalamus, basal ganglia, and prefrontal cortex, as well as fall risk factors.
Conclusion:
This thesis presents converging evidence that chronic pain contributes to mobility decline through interconnected behavioural, psychological, and neurobiological mechanisms with ageing. The findings support the use of multidimensional assessment and holistic care strategies in both clinical and research settings. By integrating epidemiological, experiential, and neuroimaging evidence, this thesis offers a comprehensive framework for improving mobility, reducing fall risk, and addressing cognitive decline through multidimensional, targeted interventions for people living with chronic pain as they age
Social determinants of health equity for people with pain: from understanding to action
No full textObjective: This article explores the role of social determinants of health in pain care, highlighting their contribution to health inequities and offering strategies for clinicians to respond to these factors in clinical practice.
Methods: This clinical update aligns with the 2025 IASP Global Year, which focuses on pain management and education in low- and middle-income countries, as well as low-income settings and priority populations in high-income countries.
Results: Social determinants of health-defined as the social, economic, and environmental conditions shaping people's health outcomes and care experiences-follow a social gradient, and disproportionately affect those facing disadvantage and multiple forms of marginalisation. They play a central role in creating health inequities, which are systematic, avoidable, and unfair differences in health between groups. Social determinants of health are upstream influences that create downstream impacts, including individual social risk factors and health-related social needs. Addressing these influences in pain care requires a multi-level approach that considers broader structural conditions alongside individual contexts. Clinicians can take meaningful action by screening for social factors, tailoring care to individuals' social needs, connecting patients with resources, establishing links within and outside the healthcare system, advocating both at the individual and system level, and critically reflecting on their biases, social identity, and the structural forces that shape health.
Conclusion: Social determinants of health are central drivers of disparities in health outcomes and pain care. Although clinicians alone cannot address structural injustice, they play a crucial role in recognising and responding to social conditions that influence care, especially for those most affected by inequities