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What teachings are being shared by weeds? Lessons from the Shoalhaven River
No full textInvasive plants present significant challenges to the health of Country. Weeds are part of substantial ecological disruptions, including along river systems in Australia. However, despite the imperative to manage them, weed control is far from straightforward. Not only is weed management difficult and costly, but weeds are often uprooted from their habitats without consideration of the desires and wishes of local people, or even consideration of the weeds themselves as agentic nonhumans and part of Country.Interventions to manage weeds often focus on the weeds themselves, overlooking the human role in their spread. This happens because conventional weed management strategies tend to treat weeds as isolated problems, rather than considering the broader ecological and social contexts in which they exist. This oversight sets the stage for the violence that permeates conventional weed management, characterised by eradication and control efforts that demonise weedy plants through metaphors of war and aggression. In this context, while conventional management approaches may prove effective in controlling invasive species, they often fail to fully resonate with local and Indigenous perspectives and the reciprocal relationships people prioritise with Country. Conventional management thus overlooks the holistic and the oneness nature of relationships that many Indigenous people have with the land. In failing to acknowledge the importance of understanding and respecting the cultural and spiritual dimensions of weed management, which are central to Indigenous worldviews, conventional weed management also fails to reassert and re-establish better relationships between people and Country that work towards healing.Indigenous approaches suggest a different way of relating to Country through weed management is possible. With recognition of the inseparable cultural and ecological connections maintained by Indigenous people who care for Country, in this thesis, I consider how the ethics and practice of care can be brought into the spaces of managing invasive plants. I examine the human and more-than-human relationships that shape attitudes and actions toward invasive plants and their management along the Shoalhaven River in NSW. Building on emerging national and international research on Indigenous relationships with weeds, I aim to shed light on ancient natural resource management solutions to contemporary problems. I develop this work as a Gundungurra woman by sharing my developing relationship with Country and the Yuin ontologies and methodological approach that helped me to learn from Country. I draw upon ancient Indigenous and more-than-human methodologies that enable me to learn from weeds and other nonhumans as a researcher. In my journey of learning, River, as she is known to me, becomes my guide. In turn, I yarn with River Country, including her weeds, engage in storytelling and gain insights from Travels (dreams) about how to relate to invasive plants in this place. Acknowledging the teachings that come from River and from the weeds themselves highlights the many reciprocal relationships they are part of and their impact on how weeds may be managed. I also develop this work by examining the relationships Aboriginal cultural knowledge holders and weed managers who are connected to and work along River have with weeds. Their perspectives, knowledge, and practices, shared with me through yarning, illustrate how Aboriginal people relate to weeds and how they learn from weeds about the health of Country and its management. From this basis, I identify existing and emergent methods that might be important for learning to live and work with weeds along River.My results demonstrate how Aboriginal spiritual, cultural and ecological knowledge, attitudes and practices toward invasive plants are bound within relationships to Country. While existing research has provided valuable information into the relationships between Aboriginal people and invasive plant management, this thesis reveals the relationship between culture, values, and practices that inform and shape Indigenous weed management. Three key themes are presented in this research. First, the theme of care highlights the importance of respect, responsibility, and reciprocity in managing invasive plants. Illustrating how invasive plants can teach people ways to manage them and communicate the health of Country, a focus on care foreshadows nurturing ways of living with weeds outside of conventional framings of them as threats or a risk to be managed. Second, I present a discussion of healing in relation to weed management, which underscores the reciprocal relationship between people and weeds, showing how weeds can be seen as teachers for healing Country. A perspective on healing shifts the focus from viewing invasive plants only as detrimental, to recognising their duality and potential to contribute to the health and restoration of ecosystems. Third, the theme of balance emphasises the Yuin ontology of oneness with all humans and nonhumans as Country and suggests that instead of positioning invasive plants purely as sources of negative outcomes, weeds may be woven into our understanding of ecological harmony and reciprocal relationships.The research I document here advocates for a weaving together of Indigenous knowledge systems and values into contemporary weed management practices, promoting strategies that are not only ecologically sound but also culturally meaningful and respectful for all involved. First, I signal a need to re-establish a deep connection between people and Country, including nonhuman entities such as Grandmother Moon and Snake, to enhance understanding and participation in weed management practices. Reconnecting the self to Country involves paying attention to natural cycles, maintaining a sense of oneness with all living things, and aligning one's practices with Country's own cycles. Second, I emphasise that a holistic approach to contemporary weed management is required. A holistic approach embeds deep respect for the nonhuman world and weaves Indigenous perspectives on care and ecological balance in order to contribute to the health of Country. By embracing these ideas, all people involved in weed management may strengthen their relationships with Country and contribute to more respectful and effective weed management.</p
Exploring Crosslinking Chemistry in Coordination Polymers
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A study on TiO<sub>2</sub> nanolubricant and graphene lubricant in micro deep drawing
No full textThe abstract for this item has not been populated.</p
Investigating men's perspectives on preventive health care within general practice: a qualitative study
No full textBackground: Chronic conditions are a major health concern. Most Australian men are overweight or obese and half live with at least one chronic health condition. Many chronic conditions are preventable and treatable by reducing lifestyle risk factors. General practice delivers a range of services, including preventive health care; however, men have been noted to have low engagement with general practice. This study aimed to investigate men's perspectives on preventive health care within general practice. Methods: Seventeen semi-structured interviews were conducted with a purposive sample of Australian men recruited from the NSW Rural Fire Service following an initial survey. Interviews sought to explore men's perspectives on engagement in preventive health care within general practice. Data were thematically analysed. Results: Two sub-themes were identified relating to men's engagement in preventive health care within general practice. 'The scope of general practice services' highlighted diverse understandings among men's perceptions of the role and value of preventive health care. Whereas 'addressing lifestyle risk factors' revealed the nature of communication and advice provided within general practice concerning lifestyle risks and behavioural change. The findings indicated that when advice is provided, men want tangible and meaningful healthcare strategies that support them in making behavioural changes. Conclusions: General practice clinicians need to prioritise preventive health care. Proactively addressing preventive health care with men and supporting them to make informed decisions about their lifestyle choices has the potential to enhance their health and reduce chronic health conditions.</p
Dragging the chain: anchor scour impacts from high-tonnage commercial vessels on a soft bottom macrobenthic assemblage
No full textInternational shipping is the backbone of the global economy with ~80% of the world’s trade (by volume) transported by ship. The potential environmental impacts of this multi-billion-dollar industry have received considerable attention, particularly emissions into air and sea. Many of these large commercial vessels lay at anchor for extended periods while awaiting their turn to enter port, and yet the impacts associated with anchoring remain virtually unexamined. Anchors can exceed 20 tonnes, with chains up to hundreds of metres in length and individual links weighing up to 200kg; there is potential for significant effects on seafloor biota where anchoring is concentrated. Filling knowledge gaps in deep-water wave-exposed environments is logistically challenging and expensive. To do so we used sediment grabs collected offshore from the Port of Newcastle (SE Australia) – the world’s largest coal export terminal – to sample infaunal assemblages in anchor-affected locations relative to reference locations (30 to 55m water depth). Polychaetes and crustaceans were the most abundant biota in the samples (~85%), whereas molluscs were very low in abundance (</p
Targeting misfolded SOD1 for ubiquitin-mediated degradation as a therapeutic strategy for ALS
No full textAmyotrophic lateral sclerosis (ALS) is a devastating, progressive neurodegenerative disease characterised by the loss of motor neurons, resulting in muscle paralysis and ultimately death, usually within 3 years of diagnosis. The prevalence of ALS is 4-8 people per 100,000, with these numbers predicted to increase as the global population ages. In most cases of ALS (90-95%), there is no family history of the disease, and the patient is classified as having the sporadic form. In 5-10% of cases, however, a family history is present, inherited mutations are identified in a rapidly growing list of genes and patients are classified as having familial ALS. While the underlying cause of ALS remains elusive, the pathological hallmark for both sporadic and familial ALS is the aggregation of proteins into large, insoluble deposits in the cytoplasm of degenerating neurons. It is still unknown if the aggregates themselves are toxic to cells, however, the misfolding of protein is likely an initial pathological event. This observation provides a valuable basis in the search for diagnostic tools and treatments.The first gene linked to ALS was superoxide dismutase 1 (SOD1), encoding an enzyme responsible for converting harmful superoxide radicals to molecular oxygen and hydrogen peroxide. There are currently over 200 ALS-associated mutations identified in SOD1. These mutations are thought to interfere with the folding of SOD1 protein into its correct three-dimensional conformation, resulting in the accumulation of the misfolded form into insoluble aggregates - a toxic gain-offunction. Currently the leading therapeutic strategy to reduce SOD1 protein levels is gene silencing through RNAi, however, this approach cannot differentiate between mutant forms of the protein and the correctly folded and functioning wild-type form. Therefore, the overarching aim of this study was to design a therapeutic tool that could specifically reduce the misfolded form of SOD1, preserving the wild-type protein. Modelled on proteolysis targeting chimeric small molecules (PROTACs), the BioPROTAC approach employs a single chain variable fragment derived from previously validated humanised antibodies that specifically recognise misfolded forms of SOD1. The scFv is fused by flexible linker to a modified E3 ligase to facilitate the ubiquitylation of mutant SOD1 and its subsequent proteasomal degradation.Chapter 2 details the design and in vivo testing of a panel of seven anti-SOD1 scFvs, fused to a truncated form of the E3 ligase, C-terminal Hsc-70 interacting protein (CHIP). The seven BioPROTACs were assessed for their efficacy at reducing soluble and aggregated SOD1mut. Across multiple cell lines, the panel of BioPROTACs reduced the amount of soluble and insoluble SOD1mut-EGFP fluorescence compared to controls. Degradation via the proteasome was confirmed by an MG132 inhibitor assay. Microscopy showed the BioPROTACs co-localising with SOD1mut and binding was confirmed by co-immunoprecipitation.In Chapter 3, the BioPROTAC was further optimised by evaluating a panel of eight different E3 ligases for their ability to degrade misfolded SOD1, using a similar suite of cell-based functional assays. Three of the eight ligase chimeras had soluble expression across the nucleus and cytoplasm, and could effectively reduce soluble and aggregated misfolded SOD1. The culmination of this work was the selection of the most effective E3 ligase combined with the most effective scFv to generate a lead BioPROTAC called “MisfoldUbL” as it specifically reduces misfolded SOD1 and acts via the ubiquitin ligase pathway.In Chapter 4, the in vivo therapeutic efficacy of MisfoldUbL was investigated in an animal model. CRISPR/Cas9 technology was used for the targeted insertion of the MisfoldUbL transgene under the human pan-neuronal, synapsin 1 promoter. These mice were crossed with SOD1G93A mice and offspring were monitored from 50 days of age with weight, neurological score and motor function assessed until end-stage. In compound transgenic SOD1G93A/MisfoldUbL mice, MisfoldUbL attenuated the ALS phenotype, preventing weight loss, protecting motor function and delaying disease progression. In female mice, onset of disease was also delayed. Post-mortem analysis of an age-matched cohort at 90 days revealed an increase in the amount of soluble SOD1 and a concomitant decrease in the amount of insoluble SOD1 in the brains but not spinal cords of SOD1G93A/MisfoldUbL mice. The MisfoldUbL transgene also conferred protection on motor neurons in the ventral lumbar cord in this cohort.These promising results provide proof-of-concept supporting the therapeutic potential of BioPROTAC-style protein molecules for the targeted degradation of misfolded SOD1, and warrant further investigations into delivery in a more clinically relevant context.</p
Contributions to Lattice-based Expressive Encryption Systems
No full textPost-quantum cryptography (PQC), also known as quantum-resistant cryptography, is a cryptographic method designed to be secure against both quantum and classical computers. Recent advancements in quantum computers pose security threats to many existing cryptographic primitives. Over the past five decades, there has been significant growth in the development of cryptographic primitives. However, most rely on number theoretic hard assumptions such as the integer factorisation problem and the discrete logarithm problem. In 1994 Peter Shor showed that these problems could be solved in polynomial time. Since then, there have been efforts to find other assumptions that can be secure against quantum adversaries, leading to the creation of post-quantum cryptography. In 2016, a procedure was started to assess and standardise one or more post-quantum public-key cryptography algorithms by the National Institute of Standards and Technology (NIST). Currently, there are multiple post-quantum secure platforms such as codebased, hash-based, lattice-based, etc. However, this research project mainly focuses on “lattice-based” cryptosystems—the most prominent candidates for post-quantum cryptography due to its efficiency and versatility. In recent years, lattices have evolved into a solid and comprehensive framework thanks to the discovery of key concepts and techniques. This paved the way for developing more powerful and expressive public-key encryption systems, representing a new world of cryptographic constructions waiting to be explored and utilised. Despite whether we can pinpoint the precise moment that the quantum computer era began, we need to start preparing our information security systems today to withstand quantum computing.One of the most essential cryptographic primitives is public-key encryption. It is being used to provide confidentiality for communications, data storage, and serve as building blocks for some security protocols. The need for new public-key encryption systems that are both appropriate for novel applications and resistant to increasingly potent and cunning attacks is always growing. In this thesis, we aim to build advanced cryptosystems with additional functionalities and applications suitable for a vast range of cryptographic real-life applications by carrying out the study on (Lattice-based) Public key encryptions. Specifically, we consider expressive variants of these primitives for important real-life applications such as Proxy Re-encryption (PRE) and Puncturable Encryption (PE). To be more specific, we make the following contributions to this thesis.First, we construct an Identity-based PRE (IBPRE) in the Standard model based on Lattices. This is the first concrete construction of IBPRE that is quantum-safe, and satisfies every significant property that one would anticipate in a PRE scheme. Second, we construct two quantum-safe IBPREs that are “collusion-resistant” and have better security features. Next, we study the advanced security models of PRE, namely security against honest re-encryption attacks (HRA). We examine its significance in realising the application objectives of PRE and propelling the research on HRA-secure PRE in the context of Attribute-based Encryption (ABE). We formalise the system and security models for HRA-secure Key-Policy Attribute-based PRE (KP-ABPRE) and present a concrete construction with security proofs to show that it satisfies all the properties. The proposed construction is quantum-safe and secure in the standard model based on lattices.Fourth, we construct the first quantum-safe puncturable identity-based encryption (PIBE) schemes based on two security models, which are secure in the standard model. Fifth, we provide the first construction of lattice-based puncturable key-policy attribute-based encryption (KP-PABE), which can provide a fine-grained access mechanism with decryption revocation. This builds upon the design concept of selectively secure PIBE. Lastly, we introduce a new primitive called hierarchical identity-based puncturable encryption (HIBPE), which has an adjustable key puncture and more general key delegation than PE. More specifically, these capabilities provide an effective and adaptable solution for dataaccess control mechanisms and encrypted data exchange in a hierarchical structure. We provide the definition and security model for HIBPE schemes and construct the HIBPE scheme based on lattices in the standard model. Moreover, we show a generic construction of forward-secure hierarchical identity-based encryption (fs-HIBE) from HIBPE. In fact, this enables the first quantum-safe construction of fs-HIBE. By evolving the keys with time, the proposed fs-HIBE provides quantum-safe protection for secret keys from exposure in multi-level encrypted data sharing.</p
Subtle and continuous adaptation: Understanding Middle Stone Age technological adaptations through Marine Isotope Stages 6 & 5 in the Doring River Catchment, South Africa
No full textThis thesis investigates Middle Stone Age (Early MSA; ~315-80 thousand years ago [ka]) lithic technology at three rockshelter sites in the Doring River Catchment, Western Cape, South Africa, dated to Marine Isotope Stage (MIS) 6-5. I define this study period as ‘Early MSA’ in the broadest sense – as characterised across southern Africa by the general use of local rocks, a spatio-temporal mosaic of technological adaptations, and the absence of ‘precocious’ technological and behaviour traits that emerge from MIS 4 onwards. In lieu of such novelties, the study of Early MSA has languished in comparison with the study of later periods. There is growing evidence for technological innovations in the Early MSA, namely in late MIS 5, though such instances are often short-lived, temporally discontinuous, and spatially patchy. The Early MSA’s lithic technological adaptations, often characterised as ‘generic’ and stagnant owing to their protean nature, increasingly demonstrate a heterogeneity that existing culture historic frameworks do not easily capture.The prevailing culture historic ‘technocomplex’ scheme used in southern Africa, initially developed by Thomas Volman (1981, 1984) and subsequently updated by Lombard and Colleagues (2022, 2012), features limited explicit engagement with the drivers underlying technological change. Furthermore, specific technological changes are rarely linked to underlying processes. Consequently, while the approach deals well with clear package of change such as those that occur in the Still Bay and Howiesons Poort, it struggles to accommodate the subtle variability that characterises the Early MSA.The technocomplex scheme has been delineated into three successive technocomplexes based on changes in a small number of artefact types and attributes, namely consistent use of locally derived raw material, retouched flake types of notches, denticulates, and scrapers, and changes in flake reduction methods (e.g., blades, Levallois, laminar, and so on). Scrapers and denticulates in the European Middle Palaeolithic have been shown to be poor fossile directeur, or type fossils, as their reduction acts on a continuum with their discard state reflecting continued retouch through reuse. Developed by Harold Dibble (1987, 1995) and colleagues (e.g., Clarkson, 2005, Hiscock and Attenbrow, 2003, Hiscock and Clarkson, 2007, Holdaway, et al., 1996, Lin and Marreiros, 2021), the reduction model for retouched flakes has been tested in various contexts but not for the Early MSA. The first proposition that this thesis tests is whether the retouched flakes of the Early MSA fit with strict typological characterisations, reduction mediated by retouch form, or a pattern of expedient, on-going retouch. The three rockshelters provided ~9,000 lithic artefacts across seven stratigraphic units that were analysed through an attribute-based methodology. The morphology of scrapers, notches, and denticulates is shown to be the result of on-going, flexible, and often ad hoc patterns of retouch that were more likely responsive to imminent needs than to mental templates or culturally defined production systems.The classification tool of typology for the Early MSA has been shown to be ineffective, while there is increasing evidence that the technocomplexes are time transgressive and spatially varied. This means that a critical assessment of technocomplexes for the Early MSA is required. The rockshelter Klipfonteinrand 1 formed part of Volman’s technocomplex scheme, contributing to the definition of the MSA 2b (~100-80 ka) unit that was applied across southern Africa. Klipfonteinrand 1 has largely fallen out of discussions of Early MSA technology owing to concerns over mixing. Renewed excavations at the site from 2012-2013 provide a new and better resolved assemblage with which to work. The renewed excavations showed the site to be less mixed than previously thought and older, with two Early MSA stratigraphic units - GGLBS dated to ~85 ka and PBS at ~156 ka. When tested against the defining characteristics of MSA 2b, Klipfonteinrand 1 was shown to have a low affinity to the technocomplex scheme it helped develop. While each unit contained many relevant features of their respective technocomplexes, they did not contain all of them, nor were the features exclusive to their technocomplexes. A review of coeval assemblages within the Winter Rainfall Zone and the adjacent Year-Round Rainfall Zone found greater inter-site than intra-site differences, with few sites sharing all or many technological features.From these results, the thesis turns towards models of technological organisation to illuminate the drivers of variability through the Early MSA. Technological organisation models, generally discussed in terms of mobility, procurement, provisioning, and reduction strategies, have proved to be practical tools for understanding behavioural choices in various settings. Mobility is a prime adaptive measure for hunter gatherer populations in response to changes in environmental and social conditions. Raw material procurement can provide information on scales of mobility and provisioning insights in how groups ensured they had tool making stone available. While these strategies have been used to explain the relatively short-lived Still Bay and Howiesons Poort, the preceding Early MSA has only seen rare use. Persistent features of the Early MSA such as the use of locally derived raw material, subtle technological changes, and expedient patterns of artefact production and reduction have previously limited their use. Technological organisation is the focus of the latter half of the thesis.Technological organisation models will be tested at Mertenhof Rockshelter, across three distinct stratigraphic units dated between ~112-98 ka. The site exhibits some of the highest proportions of non-local raw materials in the Early MSA, offering an opportunity to test models of mobility, procurement, and provisioning of raw materials. The sequence displays a series of subtle technological shifts over a relatively brief period of ~14,000 years. These subtle changes represent a series of tactical responses within technological organisation strategies at a similar timescale of the Still Bay and Howiesons Poort but without the associated technological turnover.Following the results from Mertenhof and the importance that mobility played in its technological signatures, the final part of the thesis looks at what may be driving these changes in mobility and site occupation across the Doring River Catchment. As the catchment is situated in a semi-arid region at the ecotone of the Fynbos and Succulent Karoo biomes and receives most of its water during the winter months with limited retention during summer, it presents an opportunity to test the influence of water availability on mobility, occupational intensity, and technological organisation though MIS 6-5. Using historical surface water data from Water Observations from Space and known raw material sources across the catchment, the final chapter finds water availability across the catchment and in the immediate vicinity of the rockshelters influenced their occupation and occupational intensity, and mobility. Technological organisation responded to changes in water availability through quicker movements during periods, greater sedentarism at others, and changes in tactical responses in core and retouched flake reduction.In conclusion, this thesis critically evaluates the existing frameworks of the Early MSA and tests models of technological organisation, finding that models of technological organisation are effective tools in deciphering the heterogeneity in lithic technology. Rather than a stagnant and protean period for Homo sapiens, the results from this thesis indicate the hunter gatherers in MIS 6-5 applied a flexible and adaptive technological repertoire and were adaptively sensitive to the changing climatic and environmental conditions present. Ultimately, there is more to the Early MSA than meets the eye, and its lithic technology should be foregrounded in understanding our species' evolutionary history.</p
Engaging with Facebook health support groups among the Australian CALD population in NSW
No full textSocial media platforms have witnessed a marked surge in recent years, facilitating real-time information exchange, communication, and transfer in the health domain. Individuals originating from countries other than Australia and speaking languages other than English are typically classified as belonging to culturally and Linguistically Diverse (CALD) groups in Australia. Nonetheless, there exists a paucity of research elucidating the driving factors that prompt consumers from CALD backgrounds to engage with health support groups on Facebook.In numerous studies, the obstacles encountered by CALD groups in accessing health have been thoroughly investigated. Concurrently, there's a notable gap in CALD population participation and engagement via Facebook health support groups. Thus, it is pivotal to explore ways to amplify engagement in Facebook health support groups among the CALD population in NSW, Australia.The aim of this study is to investigate and articulate the main factors that promote engagement among the Australian CALD population in Facebook health support groups.</p
Misunderstanding Dido: <i>Silence, Incongruity and Dido in Vergil’s ‘Aeneid’</i>
No full textThis thesis examines the incongruity of Dido’s character in Vergil’s Aeneid, whose narrative is shaped by a series of interpretive voids – absences of explanation that, far from signifying an absence of meaning, invite a range of interpretations, some of which are conflicting. Dido’s incongruity is emphasised by a narrative opacity, where literary allusions and thematic devices create interpretive tension without offering clear resolutions. These silences not only enhance the complexity of Dido’s character but also contribute to the Aeneid’s overarching enigmatic quality, resisting any attempt at systematic categorization or definitive understanding.The thesis begins tracing the development of Vergilian scholarship, with particular attention to the works of Parry, Lyne, and Edgeworth, particularly their respective approaches to the Aeneid’s "other voice," "further voices," and "silences." It challenges the interpretive framework of “voice(s)”, proposing instead that “silence” provides a more suitable framework for approaching passages with ambiguous and inconclusive meanings.The analysis then shifts to a tripartite study of Dido, structured around her life, her appearance in the afterlife, and her posthumous legacy expressed through gifts in Books 5, 9, and 11. Through this structure, the thesis provides a nuanced account of Dido’s role, contending that she is essential – yet frequently underestimated – in unveiling the poem’s most conceptually difficult passages.Ultimately, this study contends that Dido is a figure who cannot be fully understood, she is characterised by unresolved tensions, and layered meanings whose presence reflects the epic’s resistance to definitive understanding.</p