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Reimagining menopause by expanding assumptions shaping research: a scoping review of gender and sexuality diverse people’s experiences and expectations
No full textBackground: Menopause is socially coded as an experience of hormonal change which threatens the vitality and identity of (cisgender) women in midlife; yet this framing overlooks the diversity in menopause experiences across age, gender and sexuality. The significance of these less visible experiences has led to calls to broaden the scope of menopause narratives and representations across research, policy, and practice. Methods: Using an established scoping review methodology, we identified eleven articles that reported empirical research from the perspectives and/or experiences of menopause among gender diverse people (which we widened to include sexuality diverse people where some analyses were equally relevant for gender diverse people). Results: Three thematic categories were produced through our analysis, each implying a provocative expansion of assumptions about specific elements of the menopause experience, namely: timing of symptomology, gender and hormones, and sexuality and reproduction. Underpinning these findings is a pressing need for an alternative way of approaching menopause beyond its clinical characteristics, which, in turn, is carried over to the research that evidences these characteristics. Conclusions: The centering of accounts of menopause that assume cisgender and heterosexual women’s experiences to be both normative and normal constrain other social (re)imaginings. We argue for more expansive understandings of menopause beyond this normative and clinical framing to consider the more fulsome breadth of socially situated experiences and perspectives that better serves the needs of gender diverse people
Medication adherence in gout
Full text linkAim and objectives:
This research investigated urate-lowering therapy (ULT) adherence in people with gout. The objectives were to explore: (1) the use of objective and subjective measures to estimate ULT adherence; (2) factors associated with medication adherence and (3) the effect of medication adherence on health-related outcomes longitudinally.
Methods:
Data from the Gout APP trial (n=537) was used in this research in which participants were asked to complete surveys and serum urate (SU) blood tests at baseline, 6, and 12 months. Medication adherence behaviours were measured by the Adherence to Refills and Medications Scale (ARMS); scores of 12 (minimum score) were considered optimal and >12 sub-optimal adherence. ULT adherence was estimated by combining longitudinal Pharmaceutical Benefits Scheme (PBS) claims data with either (1) patient-reported doses or (2) World Health Organization's (WHO) defined daily doses (DDD) for allopurinol. Patients’ doses were estimated from reported daily doses (surveys) and PBS data plus clinical input by the team’s rheumatologist. A 16-category ULT-dispensing status variable was created, representing the changes (or no change) in the ULT dispensing status at baseline (4 ULT dispensing status categories) to follow-up (4 ULT dispensing categories). These categories included information on the frequency of ULT dispensings and ULT adherence [proportion of days covered (PDC)].
Another self-reported adherence estimate was ‘ULT taking status’, categorised as: (1) ‘not taking ULT’, (2) ‘taking ULT and adherent’, and (3) ‘taking ULT but not adherent’. Participants reporting taking ULT and ‘I always take my medications’ were considered ‘self-reported ULT adherent’.
Statistical analysis:
(1) The PDC was calculated in a 12-month period before baseline (n=108) using the formula: [(Total days covered given the estimated daily dose) / Total number of days from first to last dispensing) x 100], PDC≥80% was considered adherent, and repeated using WHO’s DDD for allopurinol. Difference between PDC calculation methods was assessed using Wilcoxon signed rank test, agreement between ULT taking status (yes/no) and ULT-dispensed status (ULT dispensed in 12 months before baseline) was tested using Cohen's kappa (κ), and positive and negative percent agreement.
(2) Construct validity of the ARMS was examined using exploratory factor analysis (EFA), internal consistency reliability using ordinal and Cronbach’s alpha coefficients, and agreement using intraclass correlation coefficient (ICC 2,1; n=487). Criterion-related validity of and factors associated with the ARMS were examined using Kruskal–Wallis test, Spearman’s rank, Kendall’s tau-b correlations, and logistic regression. Multiple imputation was used to address missing ARMS data.
(3) The longitudinal associations between ARMS scores and health outcomes were assessed in in participants who complete the ARMS at any time (n=496) using mixed, censored regression, and latent change score models (LCSMs).
(4) In 373 participants with available PBS data 12 months before and 12 months after baseline, a ULT-dispensing status variable was created. Censored regression and mixed models were used to examine longitudinal associations of this variable with health outcomes.
Results:
The mean PDC (SD) for allopurinol was 83% (21%) using self-reported dose and PBS data compared to 63% (24%) using WHO's DDD and PBS data. Sixty-three percent were deemed adherent (PDC≥80%) using self-reported dose and 23% using WHO's DDD. The mean (t(100)=7.595, p<0.001) and median (Z=6.301, p<0.001) PDC were significantly different between these methods. Good agreement between self-reported use and dispensing of ULT was found (κ=0.708, p<0.001; positive percent agreement=90%, negative percent agreement=82%).
From the psychometric evaluation of the ARMS, EFA suggested a one-factor structure was optimal and this factor accounted for 43.2% of total variance. High internal consistency (baseline ordinal alpha=0.902) and moderate agreement in ARMS scores over time was found (ICCs>0.5; p<0.001). Lower ARMS scores (indicating better adherence) predicted achieving target SU (≤0.36mmol/L; OR: 0.89; 95% CI: 0.83–0.95; p<0.001), though not ULT adherence (OR: 0.93; 95% CI: 0.81–1.05; p=0.261). ARMS scores and PDC were not significantly correlated (Kendall’s tau-b, r=−0.126, p=0.078; Spearman’s rho=−0.173, p=0.073) and no significant difference (p<0.001) was found in median ARMS scores (IQR) of 16 (14–20), 13 (12–15), and 17.5 (15–21) in those reporting (1) not taking ULT, (2) taking ULT and adherent, and (3) taking ULT but not adherent, respectively.
Worse adherence (higher ARMS score) at any timepoint was associated with higher SU (adj. β=0.005; 95% CI: 0.003-0.006; p<0.001), lower odds of achieving target SU (adj. OR: 0.87; 95% CI: 0.82-0.92; p<0.001), increased rate of gout attacks [adj. Rate Ratio: 1.02, 95% CI: 1.01-1.03; p=0.002], higher odds of reporting at least one gout attack (adj. OR: 1.12, 95% CI: 1.06-1.19; p<0.001), lower EQ-VAS score (adj. β=-0.34, 95% CI: -0.59 to -0.09; p=0.008), and higher overall work impairment due to gout (adj. β=1.39, 95% CI: 0.20-2.59; p=0.022). LCSMs revealed a lagging relationship between ARMS scores in the first 6 months and change in EQ-VAS scores (adj. γ2=-0.605; 95% CI: -0.945 to -0.265; p<0.001) between 6-12 months.
Compared to participants who were not dispensed ULT at any time (baseline or follow-up), participants who were adherent to ULT (PDC≥80%) at baseline and follow-up had significantly lower SU (β=-0.134; 95% CI: -0.156 to -0.112; p<0.001), 46 times higher odds (OR: 46.20; 95% CI: 21.68-98.46; p<0.001) of achieving target SU, and 57% lower odds of reporting at least one gout attack (OR: 0.43, 95% CI: 0.22-0.85; p=0.014) at any timepoint. Participants who were adherent to ULT at baseline but not at follow-up (despite being dispensed ULT at least twice) had a significantly lower expected SU concentration (β = -0.146; 95% CI: -0.192 to -0.099, SE: 0.024; p<0.001) and 142 (OR: 142.21; 95% CI: 26.13-773.91, SE: 0.863; p<0.001) times higher odds of being at the target SU (≤0.36mmol/L) at any timepoint.
Conclusions:
Participant-reported daily doses combined with dispensing claims enhanced accuracy of and confidence in estimating PDC. The ARMS is a reliable and valid measure of medication adherence behaviours in people with gout. Significant longitudinal associations of both the ARMS and ULT-dispensing status with many important health outcomes indicated that absolute and changing medication adherence behaviours play a critical role in changing health outcomes in people with gout. This also justifies the use of the ARMS in research focusing on gout medication adherence
Enhancing evacuation modelling using a fine discrete floor field cellular automaton model with natural step length
Full text linkFire safety remains a global concern, causing significant loss of life, property damage, and societal disruption despite ongoing risk mitigation efforts. Accurate evacuation modelling is crucial in addressing these challenges, with floor field cellular automaton (FFCA) models widely used due to their computational efficiency and ability to simulate crowd dynamics. However, traditional FFCA models often fail to capture realistic pedestrian movements, as they assign individuals to single cells and limit movement directions, reducing the realism of evacuation simulations. This thesis introduces a refined natural step length floor field cellular automaton (NSFFCA) model that improves upon traditional models by incorporating the natural step length of pedestrians. This allows individuals to occupy multiple grids and interact over a disk-shaped area, creating more realistic pedestrian movements and interactions. The algorithms are refined to make simulation results independent of the discretisation factor. Moreover, the NSFFCA model better generates density-speed relationships, speed variations and pedestrian trajectory features, producing results that more closely reflect real-world crowd movements. The second part of this thesis explores the interaction between exit choice models and local pedestrian dynamics within floor field frameworks. It reveals a bidirectional relationship between higher-level decision-making processes and local movement patterns, emphasising the importance of capturing crowd dynamics, such as trajectories, in evacuation scenarios. Finally, the thesis examines the impact of speed variation algorithms in both FFCA and NSFFCA models. This study demonstrates that in evacuation scenarios where environmental factors are heterogeneously distributed, the differing approaches to speed variation between models can influence pedestrian exposure to these factors and subsequently impact overall evacuation outcomes. This highlights the advantages of the refined speed variation approach in simulating complex evacuation scenarios with dynamic environmental conditions
Rats encode both danger and safety information during second-order fear conditioning
No full textSecond-order fear conditioning (SOFC) in rats is a protocol used to study the substrates of learning and memory in the mammalian brain. It involves three stages. In stage 1, rats receive pairings of an initially innocuous stimulus, S1 (e.g., a tone) and an aversive unconditioned stimulus (US, e.g., foot shock; first-order conditioning of S1). In stage 2, rats receive pairings of another initially innocuous stimulus, S2 (e.g., a light) and the already-conditioned S1 (second-order conditioning of S2). Finally, in stage 3, rats exhibit fear responses (e.g., freezing) when tested with the S2 alone. Previous work has shown that rats encode an S2-fear association during the session of S2-S1 pairings, and express this association during testing with the S2. However, the robustness of fear to S2 at test is somewhat surprising as this stimulus is perfectly correlated with the absence of the US. This led us to consider the possibility that, during SOFC, rats encode the relation between S2 and the absent US, which then acts as a brake on the expression of second-order fear. That is, we hypothesized that SOFC involves encoding of both S2-fear and S2-“no US” associations, which have opposing effects on behaviour; and that the final level of second-order fear reflects the balance of competition between these associations.
The present thesis tested this hypothesis. The first empirical chapter examines whether rats do, indeed, encode an S2-no US association during the session of S2-S1 pairings. To do so, we exploited the fact that safety learning is often encoded in a specific region of the medial prefrontal cortex: the infralimbic cortex (IL). Specifically, we examined the effect of pharmacologically silencing the IL on the level of second-order fear to S2. The second empirical chapter examined the consequences of any S2-no US association for changes in responding to the S1. To do so, we increased the number of S2-S1 pairings in stage 2 to bring about changes in responding to the S1; and compared these changes with those observed among rats for which S2 and S1 were not paired
Study the influence of rare earth ions on the magnetic, thermoelectric, and optical properties of perovskites
No full textPerovskite materials exhibit exceptional structural flexibility and diverse physical properties, making them highly attractive for advanced technological applications. This thesis explores the impact of rare earth ions (RE3+) on the crystal structure, magnetic behaviour and optical properties of both double perovskites and metal halide perovskites. The first part of this research focuses on the crystal structure, and magnetic properties of the Sr2RENbO6 double perovskite compound (RE = Gd, Tb, Dy, Ho, Er, and Tm). These double perovskite series were synthesised via the conventional ceramic solid-state method, with their crystal structures confirmed by X-ray powder diffraction (XRD) and the Rietveld refinement method. These double perovskites were found to be good quality and near single phase forming in the monoclinic, P21/n, space group (No.14). DC magnetisation measurements revealed Curie–Weiss paramagnetic behaviour across the series, while Sr₂TbNbO₆ and Sr₂TmNbO₆ exhibited Van Vleck paramagnetism at low temperatures. Field-induced magnetic ordering was observed, shifting to higher temperatures with increasing applied magnetic fields. Furthermore, Sr₂GdNbO₆ demonstrated a promising magnetocaloric effect at very low temperatures. Specific heat measurements were conducted on Sr₂RENbO₆ (RE = Gd, Tb, Dy, Ho, Er, and Tm) under varying magnetic fields, revealing crystal field effects in Sr₂HoNbO₆ and Sr₂TmNbO₆. The magnetic structures were determined using a refinement of the Neutron powder diffraction (NPD) patterns to be canted ferromagnetic (herringbone) arrangements. NPD magnetic contributions are well-fitted with a propagation vector k = [000] and magnetic order only at the rare earth site. The up-conversion (UC) luminescence properties of Er³⁺/Yb³⁺ co-doped Sr₂YNbO₆ double perovskites were explored using up-conversion luminescence spectroscopy. Er3+ and Yb3+ concentration-dependent UC luminescence processes were examined when excited by 980 nm light. Notably, the double perovskite phosphor Sr2Y0.845Yb0.15Er0.005NbO6 shows distinct concentration-dependent UC luminescence processes with both green (520 600 nm) and red (650 740 nm) UC emissions. Finally, CsPb0.95Yb0.05I2Br metal halide perovskite thin films were synthesised and studied under different environmental conditions. X-ray diffraction, UV spectroscopy and photoluminescence spectroscopy revealed a phase transition, reversible when the sample stored in the dark. On exposure to light, photo-induced halide phase segregation occurs, leading to the formation of iodide-rich domains during illumination
Spectroscopy of dimethylnapthyl radicals and their candidacy as carriers of the Diffuse Interstellar Bands
No full textThe diffuse interstellar bands (DIBs) are an astronomical absorption feature that were first identified by Mary Lee Heger in 1922. Spanning the near ultra-violet, visible and near-infrared spectrum these ~ 500 absorption lines have challenged astrochemists, astrophysicists and astronomers alike as to what species are responsible. Because the DIBs carriers originate in the interstellar medium (ISM) i.e. the volume of space between stars, scientists can look to the knowledge of the interstellar cycle to guide research closer to identification of the carriers to the DIBs. A large group of molecules that are thought to be responsible are polyaromatic hydrocarbons (PAHs), large interconnected carbon-based molecules ubiquitous in the ISM. In 2015, ionised buckminsterfullerene, C60+, was found to be responsible for four DIBs becoming the first and only DIB carrier to be identified since their discovery. Two classes of PAHs that have arisen from this theory are resonance - stabilised radicals (RSRs) and closed-shell cations (CSCs); due to the resonance stabilisation and the empty outer shell with high ionisation energies it is thought that these PAHs could survive the harsh conditions of the ISM. In this thesis two substituted PAH resonance-stabilised radicals that can be considered building blocks of C60+ were studied. 1,4 dimethylnaphthalene and 1,5 dimethylnapthelene were analysed for their spectroscopic properties and compared to astronomical data to assess their potential as candidate DIB carriers.
The radicals were produced in a jet-cooled molecular beam, formed from an electric discharge. A thorough investigation and comparison into the spectroscopic and physical properties of both isomers was conducted using resonance-enhanced multi-photon ionisation (REMPI) and combined with high-level electronic structure theory to assist in identification and interpretation. The first ever recorded excitation spectrum of the first excited - state of 1,5 dimethylnaphthalene radical was recorded across a range of 16666 cm-1 (600 nm) - 18400 cm-1 (543 nm) and an ionisation potential of 6.7625 eV was recorded. Similarly a spectrum of the first excited state of 1,4 dimethylnaphthalene was recorded from 17055 cm-1 - 18800 cm-1 and the benchmarked ionisation potential was calculated. Dispersed fluorescence (DF) spectra were also recorded for both isomers and a lifetime measurement of the 1,4 dimethylnaphthalene radical was taken. This has lead to a new understanding of the spectroscopy of these dimethylnapthyl radicals and their origins have then been compared to the closest DIBs. Although they absorb in the correct regions to be considered carriers of the DIBs no match could be made. Even though they are not carriers of the DIBs by having an in-depth knowledge of their spectroscopy further studies into the closed-shell cations of these radicals, which can also be compared to the DIBs as potential carriers, can now be done
Polymer–Surfactant Complexation and the Design of Future Green Personal Care Products
No full textMixed stabilisers are ubiquitous in industrial applications, as carefully selected mixtures of polymers and surfactants offer unique advantages over a single surfactant system. In personal care products, specifically, combining anionic and non-ionic surfactants in conjunction with polymers and salts provides not only colloidal stabilisation but also rheological control. Personal care product manufacturers have recognised that their current materials are not environmentally sustainable. They are seeking new surfactants; however, challenges arise when formulating blends of surfactants in understanding the adsorption behaviour and structure-function relationships of oppositely charged polymer–surfactant (PS) complexes. This thesis presents four studies that attempt to examine the adsorption behaviour at oil/water interfaces of PS complexes, looking at both current technology and potential green replacements.
The first study investigates path dependencies that may affect the adsorption behaviour at the oil/water interface of the industrial anionic surfactant (sodium lauryl ether sulfate (SLES)), two industrial cationic polymers (cationic guar (JaGuarXL) and cationic hydroxyethyl cellulose (JR-30M)), and the PS complexes they form. From quartz crystal microbalance with dissipation (QCM-D) measurements, reversible adsorption of SLES to the oil/water interface is measured, while the cationic polymers show irreversible adsorption. Neutron reflectometry (NR) shows that there are structural changes when building oppositely charged PS complexes with different orders of adding polymers and surfactants. It is found that pre-mixed complexes possessed the most favourable adsorption at the oil/water interface.
The second study examines the influence of salts on the adsorption behaviour of PS complexes at the oil/water interface, with the combination of QCM-D and NR highlighting the ability of salts to control PS complex formation. At higher salt concentrations, the adsorbed layers of PS complexes at the oil/water interface became more densely packed, consistent with literature data indicating that salts dehydrate the ethylene glycol linker group within the SC12ES surfactants. Complexes with Guar are more sensitive to salts than complexes with JR‑30M. Beyond the influence of a simple 1:1 electrolyte (NaCl), the impact of water hardness is investigated, with the adsorbed PS complex layer being more loosely packed by the introduction of synthetic hard water.
The penultimate study explores cocamidopropyl betaine (CAPB) and its role in modulating the adsorption behaviour of complexes between SLES and cationic polymers. Blending SCnES with CAPB at a 9:1 mass-ratio made the adsorbed layers of oppositely charged PS complexes more tightly packed. The addition of CAPB changes the salt response of cat-Pol/SC12ES complexes by reducing the thickness and increasing the complex volume fraction of the adsorbed complex layers at all NaCl concentrations. Complexes with more CAPB-rich surfactant blends are seen to have thicker adsorbed layers at the oil/water interface. This observation can be explained as the longer-tailed molecules of the polydisperse CAPB taking a dominant role in adsorbing at the PDMS/water interface since they are more hydrophobic.
The final study utilises the discoveries in the previous chapter to evaluate the efficacy of a newly developed alternative to CAPB named lauryl di(ethylene glycol) ester betaine (LE2EB). NR shows that complexes with mixed SLES-LE2EB at a 9:1 ratio form thicker and more densely packed adsorbed layers at the oil/water interface. The presence of LE2EB is observed to change the response to salts for complexes with 10% w/v surfactant, which suggests that the dehydration of the ethylene glycol linker group (which LE2EB possesses) due to salts also occurs for LE2EB. Most of the complexes with more LE2EB-rich surfactant blends are seen to have slightly thicker adsorbed layers at the oil/water interface. LE2EB can reproduce most of the behaviour that CAPB displays in adsorbed layers of PS complexes at the oil/water interface.
In each of these studies, interfacial adsorption behaviour of oppositely charged PS complexes can be tuned in ways that will influence the deposition of the active agents delivering of personal care products. Understanding the role of salt in controlling not only the rheology of the product but also deposition is an important part of designing the formulation. The results described here provide understanding of interfacial complex adsorption through the lens of linker chemistry and the interactions between surfactants and polymers. Use of this knowledge to study alternatives to CAPB are described here, as well as future prospects for the studies that will enable the replacement of SLES
Submission 141. Productivity Commission Harnessing data and digital technology Interim Report
No full textDecarbonising Australia’s Critical Minerals Mining via Hybrid Microgrid
No full textThe accelerating global transition to renewable energy has created a critical paradox: the growing
demand for critical minerals essential to clean energy technologies is driving increased carbon
emissions from mining operations. This challenge is particularly acute in Australia, a leading supplier
of critical minerals, where many mining operations in remote locations rely heavily on fossil fuels. This
thesis addresses this challenge by developing comprehensive frameworks and tools to advance the
decarbonisation of Australia's critical minerals mining sector through renewable energy integration.
The research develops a systematic approach through three interconnected contributions. First, it
establishes an assessment framework that evaluates renewable energy potential at critical mineral
deposits, considering factors including solar and wind capacity factors, energy generation lull times,
geographical clustering of deposits, and intrinsic mineral characteristics. This framework identifies
optimal sites where renewable energy implementation could benefit multiple co-located deposits,
particularly in remote regions beyond the national grid. Second, through analysis of Australian copper
deposits, the research identifies optimal dispatch strategies and evaluates the impact of demand-side
flexibility in hybrid microgrid systems. Finally, to address the limitations of commercial software like
HOMER, which lacks transparency in optimisation processes, the research develops Py-Microgrid, an
open-source tool that enables transparent and customisable simulation and optimisation of hybrid
microgrids for mining applications.
The Py-Microgrid package shows significant improvements in economic and environmental
performance. Using the Nelder-Mead optimisation algorithm, the tool achieves Levelised Cost of
Electricity values 30% lower than HOMER's results. The system achieves renewable energy fractions
of up to 90% when combining predictive dispatch with demand-side flexibility while maintaining
competitive costs. The predictive dispatch strategy shows particularly consistent performance,
achieving 55-65% carbon emission reductions compared to diesel-only systems.
This thesis advances sustainable mining practices by providing analytical frameworks and practical
tools for implementing renewable energy solutions. The open-source nature of the tool developed
through this thesis ensures transparency, reproducibility and the possibility of ongoing adaptation and
improvement by the broader research community. These contributions establish a foundation for future
research in areas such as integration with emerging renewable energy technologies and application to
diverse industrial operations, supporting the broader transition to sustainable energy systems
Wildlife reservoirs and viral threats: metatranscriptomic investigation of bat and tick viromes
No full textThe last century has seen a surge in zoonotic viral emergence and pandemics, driven by pathogens such as highly pathogenic coronaviruses, influenza viruses, and human immunodeficiency virus (HIV). These events have highlighted the need to complement traditional outbreak responses like containment and vaccine development. Proactive surveillance of reservoirs and vectors to identify zoonotic pathogens before emergence is a contemporary approach given the advancement of metatranscriptomics and bioinformatics.
Using these approaches, several viruses have been characterised prior to their recognition as disease-causing, highlighting the role of early surveillance in identifying at-risk populations and mitigating spillover events. This research investigates viruses in key animal and arthropod reservoirs, leveraging public and newly generated sequencing data to detect agents with human disease potential.
Chapter two explores the virome of bats, through metatranscriptomic analysis of 200 RNA-Seq datasets from 73 species. Novel viruses were identified (n=13), including a coronavirus and reovirus, across nine viral families in Chinese, Peruvian, Mexican and Dominican bats. Among these, four novel viruses were added to the astro-like viral clade that has a ubiquitous range and enigmatic zoonotic relevance.
Chapter three provides a global-scale analysis of 340 tick transcriptomes, detecting viral diversity spanning 22 families. The recognised range of known viruses (n=11) was expanded, including pathogenic Beiji nairovirus and jingmenviruses. Novel nairoviruses, Nantes virus and Brittany virus were described and new segments of the orthomyxovirus Uumaja virus were also found. The study also demonstrated that tick habitat ecotype may influence virome composition.
Chapter four focused on Australian Ixodes ticks, particularly I. tasmani and I. holocyclus, collected from pets and possums in suburban Sydney. A novel quaranjavirus was found in an I. tasmani tick. While I. holocyclus bites can be paralytic, this is the first tentative link between I. tasmani and similar symptoms. Bacterial profiling found no evidence of Borrelia burgdorferi, supporting the consensus that Lyme disease is not endemic to Australia nor linked to debilitating symptom complexes attributed to ticks (DSCATT).
This thesis demonstrates the utility of metatranscriptomics in detecting hidden viral diversity and contributes to global efforts to expand pathogen surveillance and mitigate zoonotic outbreak risk