Open Access Theses

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Open Access
Our Kapijukinen: Climate Adaptation Policy and Poetry in the Marshall Islands
(2025) Jetnil-Kijiner, Kathy
This creative thesis analyses the climate coloniality of Marshall Islands' national adaptation policies, arguing that the climate crisis is the latest continuing saga of colonialism impacting the Marshall Islands and Marshallese cultural relationships to land. This thesis presents new poetry inspired by the scholar's experiences as an activist and working in the national and international climate space, weaving in the climate crisis with the nuclear legacy, and exploring Marshallese deep time relationships to land and modern identity. It explores climate coloniality based on Farhana Sultana's article, "The Unbearable Heaviness of Climate Coloniality" (2022), and connects this to other scholarships from the Pacific, Micronesia, and the Marshall Islands. It then analyses the Marshall Islands government's policies, the Adaptation Communication (2021), the Community Consultations (2024), and the National Adaptation Plan (2024), arguing that adaptation is a form of survivance - resistance and survival - for Marshallese people as a way to protect our islands, culture and heritage. However, the policies fall short on identifying how the previous legacies of colonialism have contributed to vulnerabilities to climate change, and how climate change is yet another continuation of those colonial impacts. Woven throughout the exegesis are poems from the creative component, which is a manuscript of new poetry that engages in adaptation, climate change, and the colonial legacy.
Open Access
Touching Wires: Exploring Tactility in Human-AI Musical Co-Creation
(2024) Ma, Sandy
Tactile interaction is a cornerstone of how humans build relationships in the world, including those we create with computers and machines. This thesis details the development of a textile-based musical performance system integrated with machine intelligence to form sonic dialogues between human and machine. We use this system to explore tangible and embodied interactions within human-AI interaction. This work introduces a quilted interface that allows users to control a digital synthesis instrument based on the Bela audio platform. Configured as an interactive call-and- response interaction with machine-generated output, we investigate the role of soft tex- tile interfaces in navigating relationships between human users and computer systems. This has been explored through autoethnographic data collated from the researcher’s perspective in performing with the system, as well as user study data from participants interacting in a controlled environment. The development process of the system has been documented within this thesis, and results have been collected and analysed to evaluate the role of tactility in human-AI interaction. We find familiarity and communication as key themes in human-AI interaction. Tactility, sight, and audio all form integral access points to forming embodied understandings of novel systems. Textiles are an underexplored and novel way of inviting users in to explore interactive experiences and media.
Open Access
Competing over America in the Cold War: Australia-Indonesia Relations, 1945-1978
(2025) Supriyanto, Ristian
One contention prevailing in the literature about the Cold War is the ability of 'small and middle' or 'lesser' powers to exercise policy independence from great powers. The independence or strategic autonomy of lesser powers often succumbed to the Cold War among the great powers, making lesser powers acting like proxies of the latter. If independence was the priority, lesser powers were naturally inclined to keep the great powers at bay. Not quite was the case with these two lesser powers: Indonesia and Australia. The two countries desired the great powers to play a substantial role in the management of Australia-Indonesia relations during its formative period of 1945-1978. Why was this the case? And, how did the great powers influence the relationship between Australia and Indonesia? Drawing its primary analysis from Indonesian and Australian archives, this study argues that Australian and Indonesian leaders felt they could not meaningfully influence or alter each other's policies without great power intervention. These archives shed light to such intervention during the four continuous episodes of 'the Indonesian Revolution' in 1945-1978. This Revolution concerned Indonesia's struggles for independence from colonialism, in one form or another. While ideologically driven by anti-colonialism, the Revolution spearheaded Indonesian territorial claims and geopolitical influence beyond its borders. Looking menacingly expansionist, the Revolution stoked Australia's opposition to keep it in check, if not stall it altogether. Only by getting the support from one or more great powers did Indonesian and Australian leaders feel capable to affect the course of the Revolution. Due to their peripheral geostrategic location in the Cold War, however, Australia and Indonesia found the United States disinterested in the Indonesian Revolution, albeit it was also the most influential as it controlled the seas in maritime Southeast Asia. As shown in the four episodes, Washington's unreliable yet largely benign image prevailed in the minds of Indonesian and Australian leaders, making it the top great power of choice for both. Desiring the United States to play a substantial role in the Revolution, Indonesian and Australian leaders exercised the 'U.S.-first' and 'pro-U.S.' strategies, respectively. The aims were to compel the United States to either support Indonesia and its Revolution, or help Australia to check and even stop it. Although Indonesian and Australian strategies only met chequered success, they managed to get U.S. intervention in each episode, demonstrating the independence of lesser powers. Unlike Australia's strategy whose choices were limited to the United States and Britain, that of Indonesia was flexible enough to align with the communist Soviet Union and/or China in addition to the West. Consequently, Indonesia exercised relatively more leverage over the United States than did Australia in the four episodes. While they were competitive, Indonesian and Australian strategies brought stability to their bilateral relations. Neither Indonesian nor Australian leaders ever pursued their interests in the Revolution beyond what U.S. leaders supported or accepted.
Open Access
Sortition versus party governments
(2025) Giuliani, Adriano
This thesis explores selection mechanisms in democratic systems, focusing on sortition as an alternative to traditional electoral methods. Conducted as part of a Double Degree program between LUMSA University and the Australian National University (ANU), the research comprises three independent papers currently under peer review. Chapter 1 provides a historical analysis of sortition, tracing its use from ancient Greece to modern democratic experiments. It examines the theoretical foundations of random selection in governance, its historical decline, and its potential to enhance contemporary democracy by fostering transparency and egalitarianism. Chapter 2 introduces a theoretical framework for applying sortition within political parties. Co-authored with Prof. Keith Dowding and Dr. William Bosworth, this paper proposes a novel candidate selection mechanism where party representatives are partially chosen by lot before facing elections. This method mitigates elite manipulation while preserving party stability and electoral competition. The study argues that integrating sortition within party structures can enhance internal democracy without undermining electoral legitimacy. Chapter 3, co-authored with Prof. Matteo Rizzolli, Prof. Luca Corazzini, and Dr. Davide Marchegiani, presents an empirical study using behavioral experiments to compare the effects of three selection mechanisms—elections, meritocracy, and sortition—on policymakers’ decision-making. Findings indicate that election-based systems lead to more equitable resource distribution due to accountability-driven incentives. While sortition alone appears less effective in fostering distributive fairness, its integration within party selection processes, as proposed in Chapter 2, offers a promising middle ground between democratic legitimacy and reduced elite dominance.
Open Access
Tax Compliance Dynamics: Evaluating Behavioural Responses of Small Business to Tax Administration Interventions
(2025) Satyadini, Agung
Small businesses play a pivotal role in economic growth by driving innovation and making substantial contributions to gross domestic product, especially in developing economies such as Indonesia. However, their potential as a reliable source of tax revenue remains constrained by persistently low tax compliance rates. This thesis examines how small businesses in Indonesia respond to administrative reforms and targeted policy interventions. Through an analysis of tax structural reforms and the design of experimental interventions, this research assesses the effectiveness of different strategies in enhancing compliance and examines the long-term sustainability of tax compliance. Chapter 1 introduces the study's focus on small business taxation in Indonesia, examining its development, tax structure, and administration. This study also explores taxation from the perspectives of policymakers and entrepreneurs, shedding light on practical challenges. The chapter concludes by presenting the thesis's main research questions, objectives, and an overview of the next chapter. Chapter 2 evaluates the tax simplification programme for small businesses employing a regression discontinuity design (RDD). The analysis reveals that, while the programme did not result in a significant increase in tax payments, it led to improvements in overall compliance, particularly in tax reporting. The findings further indicate a higher frequency of filings and a reduction in penalties for late submissions, with more pronounced effects observed in regions with better internet access and proximity to tax offices. Chapter 3 investigates taxpayers' behavioural responses through a randomised controlled trial (RCT) embedded in a large-scale natural field experiment. This study evaluates the effectiveness of three treatment letters -- enforcement, information, and public goods provision letter -- in enhancing tax compliance. Additionally, the chapter explores the link between business tax compliance, geographic location, and distance, providing empirical insights from the field. Findings indicate that all letters significantly improve tax filing and payment, with deterrence letters having the strongest effect on payments and filing accuracy. The extent of responsiveness varies based on taxpayer characteristics, such as proximity to tax offices and compliance history. Targeting already compliant businesses near metropolitan area backfires, underscoring the need for geographically tailored tax administration strategies. Chapter 4 examines the long-term effects of these interventions by assessing treatment effects over 12 periods and re-administering the initial interventions as outlined in Chapter 3 one year after the original trials. The analysis demonstrates that while the effectiveness of all letters declines over time, deterrence letters show the most sustained impact, continuing to significantly influence tax payments. These findings highlight the enduring effectiveness of deterrence strategies as a tool for fostering long-term compliance, even when interventions are repeated. This thesis makes a significant contribution to the literature by offering robust empirical evidence on the behavioural responses of taxpayers to tax simplification policies and experimental interventions, with a specific focus on small businesses in Indonesia. By examining these responses, the research provides valuable insights into the complexities of tax compliance within a developing economy, where diverse socio-economic conditions and uneven enforcement capacities present unique challenges.
Open Access
When do technology transfer policies work? Exploring the Indonesian case
(2025) Surianta, Andree
Technology is a source of value generation, growth, and competitiveness. Developing countries have long tried to tap into the technologies flowing through the global value chains (GVCs) by welcoming foreign direct investment (FDI). FDI is still believed to provide the best access to technologies and the post-COVID GVC reconfiguration creates new opportunities to become a host. However, the extant literature shows that finding the right policy mix to attract FDI and capture their technologies can be elusive. Incentives to draw FDI inward often clash with industrial policies stipulating localisation. Outward FDI to acquire technology can also cause friction between host and home countries. This thesis argues that ignoring these policy trade-offs can inhibit technology transfer from GVCs and that building absorptive capacity minimises this risk. As such, it proposes a technology transfer theoretical framework that highlights the foundational role of absorptive capacity within the inward and outward access channels. This framework is empirically tested on Indonesia, a developing country that is undertaking multiple policy reforms to become a technologically advanced, high-income economy by 2045. The reforms create a variety of investment and industrial policies that focus on localising MNE activities, often coercively. Examining these policies through semi-structured interviews, regression analysis, video and document analysis, and text frequency analysis confirms the dangers of pursuing technology transfer without preparing sufficient absorptive capacity. Weak absorptive capacity makes a host location unattractive to MNEs and encumbers outward engagement as well. Drawing from these insights, this thesis proposes several alternative policies that Indonesia might pursue, focusing on the development of absorptive capacity. This research contributes to the academic and policy discourse by offering a new perspective on technology transfer policies, one that calls for minimising access obstruction and maximising absorption opportunities. By building a strong foundation of absorptive capacity, developing countries have a higher chance of securing the technologies they need to support their economic development.
Open Access
Hot subdwarf stars and related stellar objects: modelling and empirical effective temperatures
(2025) Xiong, Heran
Hot subdwarf stars are of significant importance in astrophysics, serving as unique laboratories for studying the more exotic and less understood late stages of stellar evolution. In this thesis, I present both theoretical and observational work aimed at understanding hot subdwarfs and related stellar objects across a broad mass range. Among these are the enigmatic Blue Large Amplitude Pulsators, a newly discovered class of pulsators. I demonstrate that Shell Helium Burning hot subdwarfs are strong candidates to explain this class, outperforming several other models proposed thus far. Additionally, I present insights from the discovery and characterisation of J0526, a short-period hot subdwarf binary, confirming it as the smallest known non-degenerate star in a detached binary system. I also explore the outcomes of white dwarf mergers, focusing on Helium, CO, and ONe white dwarf mergers, and show that some of these can successfully explain recently observed phenomena, such as the Gaia Q Branch and the exceptionally massive stellar remnant J005311, which exhibits unusual spectral properties. Finally, I present my extension to hot subdwarfs of the Infrared Flux Method, a technique for determining stellar effective temperatures. To achieve this, I incorporate ultraviolet and optical photometry and explore its implications for GALEX photometry.
Open Access
Digitally Enhanced Dispersion Spectroscopy
(2025) Wong, Justin
Molecular dispersion spectroscopy for the optical detection, and characterization of anomalous dispersion is a developing field for the interferometric measurement of trace gas concentrations. As a phase sensitive detection technique, it eliminates the need for baselining or normalization of the spectroscopic signal which is typically required for absorption spectroscopy methods. Furthermore, dispersion sensitive methods excel at measuring through high optical depth, where absorption techniques are limited by the exponential response required by the Beer-Lambert Law. This thesis presents novel architectures for dispersion spectroscopy using digital interferometry (DI), a laser metrology technique that enables range gated interferometric phase measurements using the correlation of pseudo-random binary sequences (PRBS) modulated onto the optical field. This enables rejection of unwanted scattered noise or other cross-talk down to microradian phase sensitivities, as well as a reduction of optical complexity and relaxation of electronic bandwidth requirements. Firstly, as a proof of concept, a Sagnac architecture is used to demonstrate digital interferometric phase extraction, achieving 2x10^-7 rad per root hertz sensitivity. Following this, a vapor cell is inserted into the sensing path, transforming the interferometer into a spectrometer. Using this instrument, and leveraging the sub-microradian phase noise, a baseband dispersion readout with 77 ppb-m per root hertz concentration sensitivity is demonstrated. This sensitivity is possible due to the inherently matched path lengths of the Sagnac interferometer. Subsequently, a more flexible in-line technique using a re-entrant delay line is developed. This creates a dispersion spectrometer which uses DI multiplexing to synthesize multiple sets of matched path lengths and a noise-suppressed measurement, achieving a phase sensitivity of 8x10^-6 rad per root hertz , corresponding to a concentration sensitivity of 159 ppb-m per root hertz. This is a factor of two higher compared to the Sagnac architecture. However, the re-entrant optical architecture allows integrated wavelength tuning linearisation as well as greater flexibility in the measurement of spectroscopic samples. Finally, the thesis discusses ongoing work on extending the optical bandwidth of the re-entrant spectrometer, using an optical amplifier to generate a digitally addressable frequency comb. This has applications in the interrogation of wider linewidth resonance features such as metasurfaces.
Open Access
Archiving Change: Film Versions and Cultural Heritage at the National Film and Sound Archive
(2025) Karpinellison, Zach
Short Abstract This thesis argues that the multiple versions of films held in the Australian National Film and Sound Archive are not simply practical or technical objects, but instead palimpsestic, process-laden records that hold the traces of a film's history and identity. The Australian National Film and Sound Archive's (NFSA) Strategic Direction document states, "The NFSA tells the national story by collecting, preserving and sharing audiovisual media, the cultural experience platforms of our time." This "national story" consists of over three million items, including multiple versions of films (what I term 'film versions') such as alternate formats, cuts and local and international releases. In its preservation and restoration practices, the NFSA necessarily prioritises some versions of a specific film over others. Focusing on four films selected for restoration, in this thesis, I argue that comparing multiple versions of a single film - a process I call 'versional analysis' - is an important and overdue exercise. This approach not only recuperates the opaque, selective process in deciding which versions of a film the Archive chooses to use for a restoration but also analyses the commercial, political and institutional infrastructure that contribute to a version's continuing existence. It offers an enriched understanding of the film artefact (the chosen version) as never simply singular, but always tethered to its other iterations. Moreover, I challenge the claim that the act of managing, preserving and restoring film versions can be reduced to a technical exercise. Instead, I show that these processes are necessarily generative. I argue that the changes made to the versions of films I analyse demonstrate the important role the NFSA plays in constructing and revising Australia's national film identity. Through a case study of unrestored and restored versions of four films held at the NFSA - those being Wake in Fright (Ted Kotcheff, 1971), Starstruck (Gillian Armstrong, 1982), Bliss (Ray Lawrence, 1985) and Proof (Jocelyn Moorhouse, 1991) this thesis critically explores how the Archive's processes of restoration and preservation actively construct its telling of the "national story". These versions, when placed into context and compared with one another, become a lens through which to view the practice of the Archive and its staff. The insights I glean from comparing these versions reveal broader implications for how the institution navigates its relationship to heritage, Australianness and national film history. I argue that the NFSA, through initiatives like the NFSA Restores program, becomes a creator or producer of new film versions. I examine these versions not only in relation to the production of the newest and most recognised instances of classic Australian films, but also in terms of their materiality. These physical and digital objects bear important relationships to historical records at the NFSA and the nostalgia they provoke. Further, these versions furnish evidence of the intersections of commerce, political policy and national memory. In other words, versions are more than echoes or memories of a film's past - they are explicit and specific instances of a film that locate it in a time and place and contribute to the dynamism of films as records of Australian history.
Open Access
Spatially resolved star formation and quenching: insights from observations and simulations
(2025) Mun, Marcie
The cosmic star formation rate density is known to have declined by a factor of ~10 to present day after reaching its peak at z ~ 2. There were drastic differences in the star-forming conditions between z ~ 0 and z ~ 2, such that galaxies in the past were more star-forming and gas-rich. Given the complexity of the star formation histories of galaxies, it is not trivial to pinpoint the exact physical mechanisms responsible for the decline from z ~ 2 to z ~ 0. To do so, it is crucial to study the spatially resolved star formation activity of galaxies across a broad range of star-forming states - from those above to below the star-forming main sequence (SFMS). In this thesis, I use the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey to investigate how galaxies have fuelled, regulated and quenched their star formation activity at intermediate redshifts (z ~ 0.3). In the first science chapter, I map radial trends in star formation for both the star-forming and passive populations in the MAGPI sample at z ~ 0.3, using a combination of the Halpha emission line and the 4000 Angstrom break as star formation rate indicators. I then compare these trends to those measured in the local Universe (z ~ 0) and at cosmic noon (z ~ 1 - 2), to capture how star formation has progressed within galaxies across ~10 Gyrs of lookback time. I capture evidence for potential evolution in radial trends for galaxies above the star-forming main sequence (SFMS), from uniformly (z ~ 1) to centrally (z ~ 0) enhanced star formation. Galaxies below the SFMS tend to quench inside-out at all redshift epochs probed. In the second chapter, I use mock observations of galaxies from the EAGLE, Magneticum, and IllustrisTNG simulations to match MAGPI observational details including the average point spread function and pixel scale. Overall, there is no agreement in radial trends between MAGPI observations and the simulations, except for galaxies below the SFMS. All three simulations agree that central and satellite galaxies are predominantly subject to active galactic nuclei (AGN) feedback and environmental processes, respectively. Different degrees of SF suppression in the centres of central galaxies are captured across different simulations, which can be explained by differences in AGN feedback recipes. In the final chapter, I contextualise the Halpha-based SFMS at z ~ 0.3 with other Halpha-based surveys in the literature, where I find no strong evidence for the evolution in either the slope or scatter of the Halpha-based SFMS out to z ~ 2. I also investigate the distribution of the Halpha-detected galaxies about the SFMS, particularly in the context of the role of galaxy interactions in determining a galaxy's offset from the SFMS. While galaxy interactions are common across the SFR - stellar mass plane, the fraction of galaxies in close (projected separations < 20 kpc) pairs is higher off the SFMS, than on the SFMS. In addition, 4 massive quiescent galaxies with nearby companions exhibit red optical colours with recent SF, along with Balmer absorption, suggesting that these galaxies may have been driven below the SFMS due to galaxy-galaxy interactions. With the MAGPI survey, this thesis extends the science unravelled by large integral field spectroscopy (IFS) surveys of galaxies at z ~ 0 towards intermediate redshifts (z ~ 0.3) for the first time, for a well-representative sample of both the star-forming and passive populations. Moreover, this thesis complements these resolved observations with an apples-to-apples comparison to three distinct cosmological simulations, providing a unique testbed to understand the effects of different physical prescriptions on the enhancement and quenching of star formation within galaxies. Overall, this thesis illustrates the power and importance of resolved studies of galaxies, especially in bridging observations and simulations, to demystify the evolution of galaxies across cosmic time.
Open Access
Characterising cyanobacterial and algal bicarbonate transporters using heterologous systems; exploring relationships between sequence, structure and function
(2025) Rourke, Loraine
Marine phytoplankton contribute significantly to global primary production, with marine cyanobacteria accounting for up to 25% of this productivity. A major factor underlying this is their carbon dioxide concentrating mechanisms (CCMs). Bicarbonate (HCO3-) transporters facilitate accumulation of intracellular HCO3- which diffuses into micro-compartments (carboxysomes) where the enzyme Rubisco is housed. Within the carboxysomes, carbonic anhydrase (CA) interconverts HCO3- and CO2, increasing the CO2 concentration available for Rubisco carboxylation. Considering the critical role HCO3- transporters play in the CCM, much remains unknown about the properties, mechanism and regulation of these proteins. This thesis addresses some of these knowledge gaps. The introduction of CCMs to chloroplasts of C3 crop plants is a focus of research to improve crop productivity as a potential strategy to circumvent looming food shortages expected as global population increases. Modelling suggests this could boost Rubisco carboxylation, increasing photosynthetic efficiency, thereby improving crop productivity. The expression of functional HCO3- transporters in the chloroplast inner envelope membrane (IEM) could support a 7-16% increase in crop productivity resulting from increased CO2 supply to Rubisco. This thesis focuses on screening members of five putative HCO3- transporter families from aquatic phytoplankton species. The primary aim of this work was to functionally identify and characterise previously undescribed sub-classes of HCO3- transporters, thereby expanding options for the secondary aim of successful integration of HCO3- transporters into C3 crop plants. An E. coli complementation system (CAfree), which lacks CA, was used to identify and characterise previously undescribed HCO3- transporters. CAfree is unable to grow at ambient CO2 unless it expresses a functional inorganic carbon (Ci) transporter or CA capable of supplying cellular HCO3- for anaplerotic pathways. Putative HCO3- transporters assessed for function were from cyanobacteria and unicellular algae (green algae and a diatom). Screening identified two families of HCO3- transporters that were functional in CAfree. Functional transporters, named SbtA2 and LCIA, were characterised using HCO3- uptake assays which measure the influx of H14CO3- in transporter-expressing E. coli. Variations of this assay assessed transporter affinity and the effects of different ions on transporter function. SbtA2 was found to be a medium affinity, high flux transporter with an apparent Cl-/SO42--dependence, whereas LCIA likely functions as a low-flux channel. SbtA2 was targeted to the chloroplast IEM of Nicotiana tabacum. Transgenic plants were assessed but showed little difference in growth and photosynthetic parameters relative to wild type plants. Transporters deemed non-functional in the E. coli system were subjected to directed evolution experiments, where CAfree expressing transport proteins were grown under sub-saturating CO2 conditions. An evolved BicA2 transporter with an "always-active" phenotype facilitated CAfree growth in air. The gene contained a single point mutation resulting in a single amino acid substitution. Sequence analysis of functional BicA members led to the identification of a native BicA2 member that was functional in E. coli. Characterisation of BicA2 in E. coli revealed low affinity for HCO3-, dependence on high Na+ concentrations, and variable HCO3- flux among homologues. These results demonstrated the identification and characterisation of previously undescribed HCO3- transporters and the potential to evolve transport proteins to become functional HCO3- transporters. This has significant implications by broadening the numbers of transporters available for use in biotechnological applications, like improving photosynthesis in C3 plants, as well as adding to the knowledge of how transporters may function in general.
Open Access
Scaling Agricultural Innovation Platform Initiated Innovations for Sustainable Smallholder Irrigation Schemes in Tanzania, Mozambique and Zimbabwe
(2025) Ncube, Xolile
Irrigated agriculture is increasingly being promoted as a solution for overcoming some of Southern Africa's food security challenges, however, many state owned and smallholder farmer managed irrigation schemes have historically been plagued by low productivity and poor returns on investment. To better understand mechanisms for overcoming the productivity and value chain challenges mentioned above, this study draws on empirical evidence from the Transforming Irrigation in Southern Africa (TISA) project that targeted ailing state-owned smallholder irrigation schemes in Mozambique, Tanzania and Zimbabwe with a unique two-pronged approach. The approach consisted of the introduction of soil moisture and nutrient monitoring tools and Agricultural Innovation Platforms. The overarching aim of this study is to determine how the scaling pathway was pursued under the TISA project and to determine whether and how this led to achieving and sustaining impact at scale for sustainable irrigation schemes in Southern Africa. Research question one is: i) what were the outcomes and impacts of AIP participatory innovation processes for direct and indirect beneficiaries? The related paper one applied the impact pathway approach for the analysis of the three participatory dimensions of i) breadth of involvement of actors ii) communication and collaboration and iii) delegation of power to stakeholders. By breaking down the impact pathway into its smallest possible components this study was able to systematically analyse the results of AIP participatory processes in order to overcome the attribution gap and determine those outcomes and impacts that were attributable to AIP participatory processes. Research question two is: ii) what social networks exist around agricultural innovations for information exchange within smallholder irrigation schemes in Zimbabwe? The related paper two applied the Social Network Analysis (SNA) approach to assess how information about the agricultural innovations facilitated from the AIPs flowed between and among irrigators at the irrigation schemes for awareness and possible adoption and scaling. The study identified irrigators that had high in-degree, in-beta and betweenness centrality as well as those with low in-closeness centrality, as actors that can be approached for the efficient dissemination of agricultural innovation information. Research question three is: iii) what were the determinants of agricultural innovation adoption choices by smallholder irrigators and government stakeholders at irrigation schemes in Zimbabwe? The corresponding paper three applied a determinants of adoption approach and found that for irrigators, observability and trialability were found to be the most important attributes considered when adopting an innovation. For government stakeholders the important attributes were relative advantage and trialability. Challenges in the continued use of some agricultural innovations were identified including the breaking down of soil moisture and nutrient monitoring tools, however, the study also found evidence of adaptation and continued use of agricultural innovations to suit prevailing conditions. The fourth and fifth research questions are: iv) what hardware, software and orgware innovations were delivered by AIPs under the TISA project? and v) what scaling approaches were utilised to scale agricultural innovations facilitated by AIPs? The corresponding paper four applied a combination of the multilevel perspective and anchoring frameworks and found that a total of 22 agricultural innovations were initiated by TISA AIPs. Differing combinations of scaling dimensions, strategies and mechanisms were adopted to anchor agricultural innovations from the AIP niche level to the sociotechnical regime levels of the irrigation schemes and government departments. It was also found that a number of these agricultural innovation were sustained throughout and post TISA implementation.
Open Access
Investigating the Carbon Uptake Physiology of Southern Ocean Phytoplankton - From Kinetics to Metal Requirements
(2025) Eggins, Sam
In this thesis, I investigate how Southern Ocean (SO) phytoplankton adapt their cellular machinery for carbon acquisition and photosynthesis. These organisms contend with unique environmental conditions, including low temperatures, dynamic light regimes, low diffusion rates, high gas solubility, and unusual trace metal distributions. I focus on three main questions: (1) how the kinetics and architecture of carbon concentrating mechanisms (CCMs) and Rubisco properties have evolved to suit cold, high CO2 waters; (2) how extracellular carbonic anhydrase (eCA) modulates iron (Fe) and carbon uptake under varying Fe availability in natural phytoplankton communities; and (3) how metabolic zinc (Zn) requirements, and potential Zn substitution by cobalt (Co) or cadmium (Cd), influence photosynthesis and growth across different SO taxa. I first explore the inorganic carbon uptake and Rubisco kinetics of two SO diatoms (Proboscia inermis and Chaetoceros flexuosus) alongside the temperate model Phaeodactylum tricornutum. Through carbonic anhydrase inhibition assays, stable isotope analyses, and ultrastructural pyrenoid observations, we show significant divergence in Rubisco carboxylation efficiency, CO2 affinity, and reliance on CCMs. P. inermis exhibits a comparatively low CO2 affinity Rubisco and reduced CCM dependence, while C. flexuosus relies strongly on extracellular CA. Temperature dependence assays further indicate that SO diatoms have kinetic adaptations optimizing carbon fixation under cold, high CO2 conditions. Then, I investigate the role of eCA in Fe and carbon uptake across different size classes of phytoplankton communities in the SO. Shipboard bioassays were conducted at the Southern Ocean Time Series (SOTS) station and near a deep chlorophyll maximum at the Antarctic Polar Front, under both Fe-amended and Fe-limited conditions. By inhibiting eCA with acetazolamide (AZ), I found that nano- and microeukaryotes displayed enhanced Fe and C uptake when Fe was abundant, whereas eCA inhibition variably affected Fe uptake under different Fe regimes. These findings highlight a complex interplay between eCA activity, Fe availability, and the efficiency of the biological carbon pump in high_latitude waters. Finally, I examine Zn requirements and the capacity for Co or Cd to substitute for Zn in carbonic anhydrase among eight diatom species and two strains of the haptophyte Phaeocystis antarctica, each isolated from distinct SO regions. Zn-dependent growth kinetics reveal pronounced biogeographical differences: subantarctic diatoms display much lower Zn requirements than polar diatoms, yet most SO diatoms exhibit limited Co substitution compared to temperate taxa. The two P. antarctica strains show moderate Zn/Co substitution, but they also require Co at high Zn concentrations, implying an essential metabolic role for Co beyond Zn replacement. Species-specific responses to Cd as a Zn surrogate were equally varied, suggesting that the elevated reliance on Zn-finger proteins in SO phytoplankton may constrain the extent of metal substitution. Collectively, these results underscore how low temperatures, and distinctive trace metal regimes (particularly with respect to Zn) shape the physiology of SO phytoplankton. An improved mechanistic understanding of these adaptations will be crucial for predicting how changing ocean conditions, such as warming, acidification, and shifting nutrient distributions, may alter carbon cycling and ecosystem function in the Southern Ocean.
Open Access
The influence of the Hebrew Bible on U2: an exploration through a Jewish lens
(2025) Dinnen, Naomi
U2 formed more than 45 years ago in Dublin Ireland and are still touring and recording and releasing music. The band has four members: lead singer Bono, guitarist the Edge, bass player Adam Clayton and drummer Larry Mullen Jnr. To date U2 has released 16 albums, including a collaboration with Brian Eno released under the Passengers moniker and one live album, several live DVDs and has written more than 200 original songs. U2 has won more Grammy Awards than any other band in history, making them one of the most successful popular music groups of all time and a major subject for scholarly investigation. The religious undercurrents in U2's secular songs, and U2's connection with Christianity has been examined by academics and the popular music press, however little has been published about how non-Christian fans connect with their Biblical messages. Some scholars refer to U2's 'universalism', their overt practice of speaking about faith and belief without tying their practice to any one denomination. In interviews with music and mainstream media, a YouTube series with Christian figure Eugene Peterson, and in his biography Surrender: 40 Songs, One Story (2022) Bono repeatedly stated that finds inspiration in the Psalms of the Hebrew Bible. The other Jewish influences on the music of U2 are more oblique, from Paul Celan whose poetry inspired the title of The Unforgettable Fire album, to Leonard Cohen, Bob Dylan and Lou Reed. In exploring the connection between U2 and the Hebrew Bible, my thesis draws on interpretations of the Biblical text undertaken by Jewish scholars throughout the ages unveiling complex religious symbolism and layers in U2's music that have otherwise been unobserved. My thesis is the first in-depth exploration of the relationship between U2's music and the Hebrew Bible and provides a framework for future research. I tested a number of approaches and methodologies to reveal the connection between U2 and the Hebrew Bible within a textual and musical context. I found that by identifying common words and phrases that are contained in U2's lyrics and the Hebrew Bible and examining their literal and symbolic meanings and their gravitas in live performance, I could ascribe new meaning and a more nuanced understanding to the way the songs are received. Bono's overt lyrical use of the Psalms continues the Jewish tradition of incorporating fragments of Psalms in songs used in communal prayers and Synagogue services. In addition, through this study I have found there are layers of intertextuality that create ambiguity and support the application of multiple meanings in interpreting U2's work.
Open Access
Circuits underlying hyperexcitability and epilepsy in the piriform cortex
Zhang, Muqin
The piriform cortex, the largest structure in the olfactory system, is essential for odor processing and plays a key role in generating and propagating epileptic seizures. Balancing excitatory and inhibitory circuits in this area is crucial, as disruptions can lead to epilepsy. A significant contributor to such imbalances is disinhibition - the inhibition of inhibitory interneurons by other inhibitory interneurons - which increases the excitability of principal neurons. This disinhibition enhances overall circuit excitability, potentially giving rise to abnormal, hyper-synchronized electrical activity. Despite its importance, the disinhibitory circuits within the piriform cortex are not well understood. To address this, the first part of this thesis mapped the connectivity of GABAergic interneuron subclasses in the deep piriform cortex of GAD67-GFP mice. Four subclasses were reliably identified: fast-spiking (FS), neurogliaform (NG), regular-spiking (RS), and bitufted (BT) cells. Following this classification, extracellular stimulation was used to determine whether these neurons received inhibitory inputs. It was found that FS and NG cells received significantly larger inhibitory inputs than RS and BT cells. To investigate the sources of these inputs, dual patch-clamp experiments were conducted, revealing that FS and NG cells established more chemical synaptic connections to other interneurons than BT and RS cells. Additionally, electrical synapses were identified, with NG-to-BT connections being particularly prevalent. Given the piriform cortex's epileptogenic nature, the second part of this thesis explored changes in the piriform cortex using a transgenic mouse model with a pathogenic HCN1 (M294L) channel mutation. Immunohistochemistry and pharmacological analyses confirmed HCN1 channel expression in the piriform cortex. Electrophysiological recordings revealed that pyramidal neurons from mutant mice exhibited depolarised resting membrane potentials and increased excitability. This increased excitability was attributed to the loss of voltage dependence in the mutant HCN channels, as evidenced by voltage-clamp experiments. Collectively, these findings suggest alterations in the piriform cortex associated with the HCN1 mutation. Interneuron subclasses in mutant mice were also examined, focusing on NG and FS cells. NG cells mirrored the hyperexcitable patterns of pyramidal neurons, while FS cells showed unchanged resting membrane potentials but reduced excitability. To investigate the mechanisms underlying these contrasting behaviours of FS cells and pyramidal neurons/NG cells, computational modelling was done. The simulations suggested that differences in the location of the axon initial segment (AIS) and the distribution of HCN1 channels could explain the observed firing patterns. Specifically, a proximal AIS with mutant HCN1 channels on the soma replicated the hyperexcitability of pyramidal neurons, whereas a distal AIS with mutant HCN1 channels between the soma and AIS replicated the reduced excitability of FS cells. Overall, this thesis stresses the roles of FS and NG cells as disinhibitory interneurons in the piriform cortex, emphasising their contributions to modulating global inhibition. However, the second part shows that these contributions can be complex, depending on the type of epilepsy. In the HCN1 epilepsy model, NG cells exhibit enhanced intrinsic excitability which may partially counteract the elevated excitability of pyramidal neurons. In contrast, FS cells exhibit decreased excitability, potentially contributing to elevated circuit excitability. However, since both FS and NG cells also strongly inhibit other interneurons, their impact on the circuit is likely to be multi-factorial. These findings highlight the need for further investigation to fully understand the interplay between inhibition and disinhibition and its consequences for generating hyperexcitability and epilepsy in the piriform cortex.
Open Access
Trace Element Characterisation in the SABRE and CYGNUS WIMP Search Experiments
(2025) Dastgiri, Ferdos
This thesis reports on various experimental developments for the SABRE South and CYGNUS experiments, with a focus on the characterisation of trace elements so as to achieve the high levels of detector purity required to attain world-leading sensitivity for Weakly Interacting Massive Particle (WIMP) direct detection. Intrinsic impurities in NaI(Tl) crystals for the SABRE South experiment were measured, including $^{40}$K, $^{238}$U/$^{232}$Th decay products, $^{210}$Pb, and the Tl dopant concentration profile. An external company, ALS, was used to make ICP-MS measurements of thallium and to assess the feasibility of low level potassium measurements. Tip and tail cut-offs of an ultra-pure crystal (NaI-35) produced by RMD were used, requiring the development of extensive chemical decomposition techniques to produce ICP-MS samples. The results confirmed a long suspected inhomogeneity in the concentration of thallium throughout the length of the crystal, and lower than expected average concentration, which may have implications for the crystal light yield and possibly the quenching factor. For $^{39}$K, the lowest detection limit at ALS was 10~ppb, and it was determined that cleaner laboratories would be required for the sample preparation. The measurement of $^{210}$Pb in NaI(Tl) using Accelerator Mass Spectrometry (AMS) requires a lead carrier with low intrinsic $^{210}$Pb levels. An old Roman lead sample from the Laboratori Nazionali del Gran Sasso (LNGS) was chemically treated using column chromatography and acid transformation to create an AMS sample, which was measured at the ANSTO Vega accelerator. The $^{210}$Pb content was two orders of magnitude lower than required for use as a carrier with NaI(Tl), proving viability for a future AMS measurement. The ability of AMS to measure $^{210}$Pb at such levels is potentially transformational for future dark matter detectors. Direct background counting of $^{238}$U and $^{232}$Th decay products in NaI-35 was performed underground at LNGS. Coincidence tagging of alpha and beta decays (slow and fast bismuth-polonium chains) as well as triple alpha decays were used to characterise the $^{226}$Ra and $^{228}$Ra radioisotopes that are believed to be in secular equilibrium with their daughters. The measured time difference distributions were fitted to exponential decay functions with a constant background using a log-likelihood minimisation. The $^{226}$Ra activity was determined to be 2.80$\pm$$^{0.36}_{0.41}$~$\mu$Bq/kg, with the best fitted half-life of 142~$\mu$s agreeing within 1$\sigma$ of the literature half-life of $^{214}$Po, providing extra confidence in the deduced activity. The bismuth-polonium and triple alpha decays below $^{228}$Ra, yielded results of 1.58$\pm$0.69~$\mu$Bq/kg and 2.91$\pm$$^{0.35}_{0.47}$~$\mu$Bq/kg, respectively, for its activity. A prototype TPC in an approximately 20~L chamber was constructed and coupled to a Residual Gas Analyser (RGA). This system was used to measure increases in electronegative impurities in pure CF$_4$ gas, as well as their effect on Gas Electron Multiplier (GEM) gain. As much as a 19$\%$ drop in gain was observed when there was a 6$\%$ rise in electronegative impurity concentration. Additional work for SABRE South and CYGNUS is also described, including the development of a trigger system for SABRE South and a gas system for CYGNUS. The latter is capable of supplying gas mixtures at controlled pressures and has been designed with expansion capabilities for radon and other impurity filtration, paving the way for future large scale gaseous TPCs.
Open Access
Order and Disorder: Aspects of Homeric Hospitality
(2025) Sweet Formiatti, Fiona
Homeric hospitality is a total social phenomenon in which interactions with the 'other' are regulated to maintain social order and to confer mutual benefits on guest and host alike. The theatre of social interactions in Homeric society is the oikos. The underpinning principles of paradigmatic hospitality are respect by guest and host for the role of the other and willing co-operation in fulfilling these roles. The principles reflect divine impetus, which is expressed in themis, and the social necessity of dealing with the ambiguity of the stranger. Transgressions of hospitality are of concern to the gods, notably Zeus Xeinios, because such disrespect represents a threat to order which has a cosmic dimension. Hence, transgressors incur divine displeasure, and corrective action is needed. In the Odyssey this falls to Odysseus: he kills the Suitors in an act of personal revenge, in which he becomes an instrument of divine punishment. I explore the Homeric meta theme of the restoration of order through hospitality which plays out as the key driver of complicating action and as a thematic and structural anchor in the Odyssey, my primary focus. Hospitality colours in the background to the Iliad, but it comes to the fore on occasion, notably in Priam's visit to Achilles. The restoration of order in the Odyssey is observed at a societal level through Odysseus' nostos. Key findings are the identification of the podalic motif of disrespect and the significance of the seer Theoklymenos in his own right as a refugee. Order is restored in the Iliad at an individual level through the resolution of Achilles' wrath, in which the transformation of ransom into hospitality is crowned by Achilles' repurposing part of the ransom for Hektor's body into a xeineion for Priam. This study offers new insights into the Homeric epics and makes an ancient-world contribution to the expanding multi-disciplinary field of hospitality studies.
Open Access
Essays on the microeconomics of flooding: economic impacts, behavioural factors and index-based insurance
(2025) Cobian Alvarez, Jose
Floods are a global threat, affecting a quarter of the world's population, most of whom live in developing countries. They have severe impacts on welfare and poverty, although coping mechanisms can mitigate these effects. Accurately measuring flood impacts is crucial for assessing their economic consequences and understanding household responses and behaviours. Additionally, substantial losses in urban areas have increased interest in risk transfer products such as index-based insurance, which can offer financial protection, promote sustainable development, and enhance resilience to weather shocks. However, most empirical research on index insurance has focused on rural settings, where farmers are typically insured against income risks from rainfall variation or drought. This dissertation addresses these gaps by proposing a novel method to estimate the economic impact of floods and by offering evidence on coping mechanisms in a middle-income country such as Peru. It also provides new evidence on factors -such as basis risk, time and risk preferences, price, and trust- that influence the adoption of index-based flood insurance in the urban contexts of Jakarta and Lima. Chapter 2 analyses demand for hypothetical index-based flood insurance in Jakarta, using household data collected in 2018. Employing a probit specification with plausibly exogenous variables (basis risk, price, and extreme risk aversion), the study finds that demand decreases with basis risk, price, and risk aversion. A policy recommendation highlights the investment in more floodgate stations, particularly in western and southern regions, to reduce basis risk and increase insurance uptake. Chapter 3 examines the effects of the 2017 coastal El Nino floods on welfare and poverty in northern Peru. A novel damage index, constructed using remote sensing within the SWAT model, is combined with five years of panel data in a Difference-in-Differences Event Study. Results show that floods reduced income and expenditure per capita while increasing poverty, especially in urban areas. Households smoothed consumption mainly through disaster relief. The development of disaster insurance that bridges the gap between aid and actual losses -estimated at PEN 818.51 (USD 251.02)- could significantly enhance flood resilience among affected households. Chapter 4 explores the role of economic preferences, price, and trust in shaping demand for index-based insurance in Lima. Using household data from a lab-in-field experiment, I leverage the exogeneity of time and risk preferences, and price. The study shows that demand rises with time preference (measured by choices of larger, delayed payoffs) but falls with extreme risk aversion and price. Notably, trust in government flood mitigation plans increases willingness to purchase insurance among highly risk-averse households.
Open Access
No man’s land: How women in prison and correctional officers perceive and negotiate formal and informal codes of conduct in an Australian prison
(2025) Dossetor, Kym
Imprisoned women differ from their male counterparts. Research has found that, compared with men, imprisoned women encounter additional social controls, navigate more complex interpersonal relationships with fellow prisoners and prison officers, and experience a different prison culture. Over the past 70 years, research has examined rules and rule-breaking in men's prisons. Far less attention has been paid to women's rule-breaking, and little is currently known about how imprisoned women negotiate and respond to prison governance systems. Therefore, it is crucial to consider how women's varying experiences and treatment in prison influence their decision to comply with the various codes of conduct existing in the prison. This thesis explores how imprisoned women and corrections officers in an Australian prison negotiate rules. It challenges the dominance of male-focused accounts of prison and rule-breaking behaviour in the criminological and policy literature. To accomplish this, this study brings literature from criminological studies into conversation with sociological scholarship on justice, power, resistance, and gender dynamics. Ch 1 introduces the research problem, outlines an initial review of the literature on rule-breaking in a women's penal context and articulates the purpose of the study. Ch 2 presents an analysis of women's penality and theories for understanding imprisoned women and their rule-breaking behaviours. It also demonstrates how most research has taken a quantitative approach primarily focused on interviews conducted with male prisoners. Ch 3 provides an overview of the research design and methods used in the study, describing the 20 imprisoned women and 14 officers from a prison in NSW who participated. Ch 4 to 6 draw on qualitative interviews with imprisoned women and prison officers. They examine how the prison environment, culture, and the complex interpersonal interactions occurring among imprisoned women and between officers and women influence rule-breaking behaviour and associated outcomes. Ch 4 explores how a structured and infantilising environment imposes social control on women, influencing both their compliance and rule-breaking behaviour. It also attends to the negative effects of gendered resources and the impact of sexualised treatment by male officers on women's behaviour in prison. Ch 5 examines how some women selectively and periodically used violence to uphold the prison code and retaliate against perceived violations, while trying to conceal such action from authorities. This chapter demonstrates women's various strategies for maintaining safety and order and providing/receiving emotional support, all while navigating the formal and unwritten prison rules. The framework of procedural justice (PJ) is applied in Chapter 6 to analyse the interpersonal interactions and power dynamics between officers and incarcerated women, particularly as this relates to the enforcement of rules and punishment of infractions. This study highlights how rule enforcement practices are applied and how officer integrity significantly influences the experiences and perceptions of women in prison - and their corresponding relationships with corrections officers, other prisoners and their wider social networks. Overall, this thesis produces rich empirical data on women's experiences of prison rules and culture. Contributing conceptual insights to the field of criminology, it also improves understandings of the complex interrelationships existing between officers and imprisoned women, to better inform gender-sensitive and research-led policymaking. It highlights the importance of processes of fairness, justice, and resistance in research on imprisoned women, contributing to enhanced visibility of the unique and diverse challenges this population faces while in the penal system. Addressing these issues is essential for improving how prisons respond to and manage the experiences of imprisoned women.
Open Access
Generation and imaging of structural laser beams for optical trapping of airborne particles and light-matter interaction applications.
(2025) Lavin Varela, Sebastian
Recently emerged non-diffracting optical Bessel-Gaussian beams have extended the `optical toolbox' in laser interaction with matter studies, providing many techniques that are not possible using conventional Gaussian beams. The research work performed under this thesis focuses on the design, generation, re-configuration, and exploration of the flexibility of BG beam for a broad range of studies of laser-matter interaction. The numerically modelled BG beam structures are experimentally tested and applied in two substantially different experimental environments. These include the generation and re-imaging of a dynamically varying BG beam, whose morphology is shaped using a Spatial Light Modulator for low-intensity applications and the generation of a static Bessel beam shaped by an axicon to be used with high-intensity femtosecond laser pulses. The first set of experiments explores the construction of a slow-diverging optical funnel based on the generation of a higher-order BG beam using a continuous wave (cw) laser beam and a SLM. The use of hollow-core BG beams have already been demonstrated for pipeline-guiding of sub-micron particles and biological macromolecules in experiments of protein nano-crystallography using x-ray diffracting imaging. The particle dynamical interaction with the beam relies on two fundamental light-induced effects that can be applied on matter, namely, radiation pressure and photophoresis. Here, we generate a SLM-formed BG beam with variable topological charge in combination with different re-imaging systems that enable us to create flexible output beams. We also demonstrate the flexibility in controlling the beam shape, the diameter of the central dark core and the angle of divergence. As a result, the analysis of trajectories of the particles trapped inside the funnel and the modelled intensity distribution of the beam allowed us to evaluate the optical forces exerted on the sub-micron particles and uncover, for the first time in our knowledge, the temperature gradient across the particle surface, which is of paramount importance for laser guiding biological particles in airborne environments. The second set of experiments investigates the construction and re-imaging of zero-order BG beam using axicons for high-intensity laser-induced cylindrical microexplosion in transparent dielectric media. A comparison between numerical modelling and the experimentally constructed BG beam using a commercially available axicons reveals that the origin of the observed undesirable intensity modulations along the beam propagation is due to the imperfections of the axicon shape. That knowledge was applied to manufacture an in-house perfectly shaped axicon and to construct the BG beam which near-ideal intensity distribution highly correlates with the numerical modelled beam. The application of the non-diffracting beam generation setup together with a reimaging system allowed us to produce high aspect-ratio elongated nanovoids inside a pristine sapphire crystal when high-intensity femtosecond laser pulses. Careful consideration of the numerically predicted intensity distribution of the beam inside the crystal and the resulting length and diameter of the nanochannels enable us to demonstrate higher energy concentration in the cylindrical geometry with BG pulses compared to the spherical geometry, common when Gaussian laser pulses were used. The close correlation between numerical and experimental generated beam allowed us, for the first time to our knowledge, to determine the nanochannel formation intensity threshold of 7.2 x 10^{13} W/cm^2 in sapphire. The numerical modelling of the flexible zero- and higher-order BG beams performed in these studies and its application to very different experimental conditions of light-matter interactions is highly advantageous, as they allow tuning of laser parameters in terms of the beam structure and intensity distribution to match the required interaction conditions.

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