Restricted Theses

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Building resilient optical ground station networks with atmospheric characterisation and modelling
(2024) Birch, Marcus
Optical communication over free-space is heralded to be a revolution for satellite telecommunication that will amplify the data capability of satellites, support future space exploration, and bring the world closer through high-speed relays. Laser links capable of modulation up to Tbit/s are promising but despite such promise this technology has long struggled with adoption for space-to-ground links due to the challenges of Earth's atmosphere. Atmospheric attenuation from cloud and turbulence are the core impediments of the atmospheric channel. Cloud cover presents an impenetrable barrier in nearly all cases for space-to-ground links, and so well-placed sites along with proliferation have long been accepted as the only solution. Atmospheric turbulence can create phase and intensity noise that limits the data rate of optical links, and is far more complex than cloud to characterise and model. Overcoming both of these problems requires new solutions on where to place optical ground stations (OGS), and new ways to measure atmospheric turbulence at those sites. I therefore addresses two core questions which arise from overcoming the atmosphere, i.e. how should ground networks be designed for resilience against cloud-induced outages, and how atmospheric turbulence can be characterised. I present novel methodology for analysing the capability of OGS networks with a focus on Australia, leveraging remote-sensing data and orbital simulations to show not only how the region is well-suited to optical communication, but utility of these analysis tools. Among these methods is a semi-analytical solution to reliability for spatially-correlated nodes, and a spatially-resolved means of node placement optimisation. These methods are extended to the poles, where further simulations and meteorological instruments installed at Davis Station, Antarctica, are used to provide a compelling case for the poles to host an OGS. This includes leveraging a machine-learning approach to cloud phase classification in-situ to refine outage predictions in polar climates. The network frameworks presented here synergise with the development of a novel turbulence monitor that can be easily deployed at prospective sites. An automated Ring Image Next Generation Scintillation Sensor (RINGSS) is constructed and tested at a number of locations, including a proof-of-concept campaign at urban sites in Europe and the Arctic. An infrared RINGSS variant is also built and deployed at the NASA/Jet Propulsion Laboratory OGS, where I demonstrate the first profiling of atmospheric turbulence using a spacecraft laser terminal, and the first use of RINGSS in daytime. Presented results in OGS network analysis and atmospheric site-testing are grounded in the ongoing development of an Australasian network, and a ANU OGS node that has been constructed over the past three years at Mount Stromlo Observatory. My research therefore establishes a comprehensive toolkit to help design and deploy free-space optical communication networks, and significantly improve their resilience and efficiency. Reliable optical ground station networks will form the backbone of a future satellite communication landscape which will amplify all of humanities future endeavours in space and on Earth in much the same way that radio antenna revolutionised telecommunication.
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Advancing 3D volumetric imaging with computational optics for in vitro tissue model
(2024) Xu, Tienan
In vitro 3D tissue model is superseding 2D cell culture model because it has shown to replicate in vivo tissue level functions processes down to single-cell level. Accurate quantification of the 3D spatial distribution of physical or molecular markers within in vitro 3D tissue model identifies cell and tissue characteristics that are subsequently used to screen for drug targets. Fluorescence techniques equipped to acquire 3D volumetric images such as light sheet and lightfield computational imaging have emerged as promising candidates to fulfil low phototoxic volumetric image-based screening of in vitro 3D tissue model at single-cell resolution. However, these 3D volumetric imaging techniques are laden with optical and practical challenges that lead to limited axial sectioning along with sample and mechanical interventions. These obstacles in turn fail to accelerate further innovative progress in applying 3D volumetric imaging in drug discovery. The aim of this thesis is to achieve isotropic 3D volumetric imaging with computational optics so that it is applicable for high-throughput screening of in vitro 3D tissue model. In Chapter 1, I first provide an overview of different classes of in vitro 3D tissue model and the hurdles in implementing light sheet fluorescence microscopy (LFSM) for volumetric image-based screening. Next in Chapter 2, I discuss the foundations of 3D volumetric imaging by providing the theoretical background of axial sectioning, reviewing the optical techniques for voxel generation in 3D, and outlining how to achieve isotropic spatial resolution. In Chapter 3, I provide detailed biochemical protocols for the fabrication of in vitro thrombosis model and the fabrication of in vitro 3D stromal tissue model using fluid viscosity modifiers. In Chapter 4, I attempt to address the challenge of refractive index (RI) difference faced by LFSM for 3D volumetric imaging. I formulate an RI matching protocol with sucrose solution and tunable illumination to enable LFSM to image single platelets in in vitro thrombosis model. Whilst the technique developed for LFSM in Chapter 4 is suited for one class of in vitro 3D tissue model: tissue-on-chips, it is still not broadly applicable to all in vitro 3D tissue model such as spherical tissue model in multi-well plates. Hence, in Chapter 5, I move to propose a novel technique that combines single objective light sheet (SOLS) and lightfield computational imaging to achieve multi-directional SOLS. Multi-directional SOLS achieves flexible 3D volumetric imaging because it can accommodate planar illumination of many different oblique and azimuthal angles. At the core of the multi-directional SOLS technique is the Fast Optical Ray lightfield reconstruction algorithm because the FOR algorithm facilitates 3D volumetric imaging with axial sectioning that reaches near-isotropic spatial resolution. Chapter 5 describes the numerical modelling and simulation of the FOR algorithm and multi-directional SOLS. Based on the technique proposed in Chapter 5, I then detail the optical design and construction to create the multi-directional SOLS system, termed the mcSOLS in Chapter 6. Chapter 6 ends with a preliminary demonstration of the mcSOLS for 3D volumetric imaging of in vitro 3D stromal tissue model that was fabricated in Chapter 3, where I show the single-cell resolution of 3.59x3.63x4.56um in a volume of 270x270x40um. In Chapter 7, I push the capabilities of the mcSOLS beyond imaging and into photolithography. I investigate, numerically and experimentally, the feasibility of implementing the multi-directional planar illumination of the mcSOLS for tomographic photolithography. Lastly, I conclude in Chapter 8 on how the development of 3D volumetric imaging techniques and in vitro 3D tissue model in this thesis exemplifies the synergy between optics, biology, and fabrication for advancing volumetric image-based screening. This paves the way for the next generation of drug discovery platforms.
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In Plain Sight: Representing Girls in Art History and Public Art Museums
(2024) Remer, Ashley
Over the past twenty years, the emergence of girls as research subjects in various disciplines has established the relatively new field of girls' studies. Yet, art history, even from a feminist perspective, has largely overlooked girls as subjects. For centuries, girls have been active in cultural production as models, performers, and artists. But firsthand accounts from their own perspectives are scarce. Because of this absence from the traditional historical records, and despite their numerous depictions in art, girls are consistently excluded from art history and curatorial discussions. This dissertation addresses girls' marginalisation and their absence in art historical discourse and museum practices by exploring the question, "What is the place of girls in art history and museum practices?" This research highlights the neglect of girls in art history and argues that the perceptions and assumptions of adults have overshadowed their identities and narratives. In doing so, it addresses a significant gap, one that is a product of systemic sexism, misogyny, and adultism within the discipline. To investigate these issues, this study develops and utilises a girl-centred theoretical framework that draws from feminist art history and girls' studies. Through this framework, the research uncovers and critiques layers of patriarchal privilege and learned misogyny that have contributed to the denial of girls' agency in art. It examines how girls are represented and discussed in art history and museum contexts, proposing ways to recover their voices and narratives. This study adopts a mixed-methods approach to answer the research question, combining traditional and innovative art historical and museological methodologies. Through document and visual content analysis, it evaluates selected artworks from the sixteenth to the early twentieth centuries in Anglo-Euro-American art history. It uses case studies of girl models from late nineteenth-century French artworks to show ways of recovering their stories. Semi-structured interviews with art historians and curators are conducted to understand their attitudes and perceptions towards girls' representations in art. The study employs an empathy walk tracing the path of girl model Marie van Goethem and gallery walks to quantify girls' presence in several European art museums. This dissertation argues for the expansion of feminist art historical discourse to acknowledge girls as valuable participants in cultural production and to include them in broader discussions and analyses of artworks. The evidence collected in this study reveals how art historians and curators view girls in art history and how they interpret them in public art museums. Despite the lack of scholarship on girls, they are ubiquitous: present in artworks, archives, art collections, and on gallery walls. This study offers new methods and analytical tools for application in art history and museum practice. Its findings contribute to emerging research on girls' representations in art, girls' studies, and child history.
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An Exploration of Complex Unbounded Problems
(2024) Weiske, Peter
CUPs Putative Abstract: Peter Weiske 2024. This thesis presents a post-modern exploration of complex unbounded problems (CUPs), seeking to provide generally applicable insights into their overall character, an effort that may inform a number of strategies to address them. Here, CUPs are serious systemic poly-domain disruptions, as complex threat risk situations far beyond the normally encountered routine problems, and although at times related to but also distinctly beyond the more common and tractable non-routine problems as described in disaster literature (e.g. Handmer and Dovers, 2013) and confronted by strategic, planning and response agencies. My first proposition is that a broader-than-usual grouping of CUPs is valuable and needed, across disasters, technological threats, humanitarian crises, security and conflict, planetary environmental degradation, widespread economic crises, and dangerous geopolitical situations. CUPs thus span those stemming from human (anthropogenic) causes and from natural (naturogenic) processes, and those that are more common in having their roots in both causal complexes. Most literature and indeed policy and responses treat these admittedly already large and complex domains separately. This wider grouping allows consideration of commonalities and variations across situations and disruptions. I propose CUPs thus categorized, have commonalities at least at a broad strategic and conceptual level, while endlessly displaying the latter in their specific manifestations and particular features. This is consistent with, but widens the scope of, Ducote's et.al (2010) PMESII+ model (political, military, economic, social-ecological, informational or infrastructural) which we have modified to incorporate the social-ecological domain; works with information-action (Polkinghorne, J. 2006); is supported by Max-Neef's Human Scale Development (HSD) (1989, 2010); fits with Complex Systems theories (Bar-Yam, Y. 1997, 2002, 2003), (Ackhoff, R.L.1994); (Holland, J.H. 1992, 2014); and those models, means and methods found in related scientific and warnings analysis fields (Grabo, C. 2003, 2010) and (Kent, S. 1949). The second and third propositions involve a number of attributes characterize CUPs in their many and deeply worrying forms. The key attributes of CUPs identified and explored here are coalescence; exceedance; porosity and unsoundness. A critical concept throughout is that of information-action, following Polkinghorne (2006), and the related phenomena of actioner and trajectorates, whereby the vectors of dynamins cause change. As an admitted eucatastrophist (sensu JRR Tolkien 1942), seeking perhaps optimistically hopeful endings amidst dismal prospects, and to counterbalance the apparent entropic direction of global problems, I respond with the idea of anti-entropy. Along the way, sub-attributes emerge and are noted. CUPs chapters: Introduction and general concepts; 2). Earth System; 3).Complex Civil Nuclear Disasters ; 4). Biologics; 5). Near earth Space Ecology; 6). Summary and Conclusions. The three propositions relate not only sequentially. If key attributes such as those above are indeed observable across varied CUP situations (proposition 2 and 3), then the validity of (proposition 1) is supported.
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A Case Study of Women Branches of Islamist Parties; Jamaat-e-Islami Pakistan and AK Party Turkey
(2024) Malik, Tayyaba
This thesis examines Islamist women's political activism in the late 2010s and early 2020s in Pakistan's Jamaat Islami in comparison with women from the Turkish Justice and Development Party (AK Party). Jamaat Islami serves as the main case study, while the AK Party serves as a comparison group to help identify what is distinctive in the experiences of Jamaat Islami women and what is shared across various Islamist movements. This thesis uses a range of qualitative methods from gender studies to examine the voices of Islamist women within these groups. It mainly draws upon interviews conducted between 2018 and 2020 with women members, male party officials, and academics providing valuable firsthand insights into Islamist political groups. By analysing interviews and data gathered from observing group meetings in the broader context of historical discourses and party documents, the study examines the conception of ideal femininity within these two Islamist parties, investigates why women choose to join conservative parties that might restrict their freedom, and considers the role of conservative political engagement within a diverse feminist landscape. Through these three themes, the thesis delves into the possibilities and limitations Muslim women in these parties face in the contemporary time. The central argument of the thesis is that Islamist women in Pakistan and Turkey, during the 2010s and 2020s, continue to find meaning and agency by actively supporting conservative political groups within the framework of gender hierarchy. By capturing the voices and perspectives of individuals involved with these groups, the study demonstrates that trends identified in the earlier studies on Islamist women in the 2000s have grown stronger. The thesis highlights that Islamist political groups in Pakistan and Turkey negotiate rather than resolve tensions between quests for women's greater empowerment and social pressures to maintain gender hierarchies. In this study, despite the socio-cultural differences between Pakistan and Turkey and their varying state-religion relationships, commonalities in the notions of ideal femininity and the motivations for women's participation in Islamist political parties have emerged. The study establishes that the examination of the ideal woman in different cultural and political contexts reveals striking similarities between JI and AKP, suggesting a convergence in Islamist ideologies that transcends national boundaries, and raises intriguing questions about the persistence of shared features despite Turkey's history of secularization and Pakistan's history of Islamization and resistance to colonial modernity. The motivation behind women's involvement in Islamist political groups is driven by a variety of factors, including the opportunity to strengthen social and familial bonds, access new educational and social avenues, pursue moral ideals, engage in a socially acceptable form of modernity, and advocate for women's well-being. However, this engagement comes with an implicit expectation to uphold patriarchal structures in exchange for these opportunities. The study also highlights the potential for considering this work within the framework of Islamist feminism, despite the rejection of feminist identity by women activists in both parties. Notably, women in the Jamaat Islami party in Pakistan experience a higher degree of freedom and autonomy compared to their counterparts in Turkey, shedding light on the nuanced dynamics within these political movements.
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The Development of Amino Acid Sulfinate Salts as Tools for Peptide Modification
(2024) Hammond, Joshua
Modified peptides, including compounds inspired by nature, have increasingly become a valuable area of research due to their growing prevalence in medicinal chemistry. To fully exploit the potential of peptide natural products and their derivatives, novel techniques must be developed to access these compounds in a laboratory setting. Techniques which can mimic the site selectivity of enzymatic post-translational modifications are particularly valuable. One conceivable approach is the development of novel amino acids bearing unique functional groups that impart new reactivity onto a peptide. In this thesis , the synthesis of novel amino acid sulfinate salts as valuable precursors to amino acid radicals is explored. The established radical reactivity of the sulfinate moiety is ideal as the conditions for radical formation are generally mild and selective and radical transformations can often proceed orthogonally to polar functional groups , including the diverse functionality present in peptides. This work discloses the synthesis of amino acid sulfinate salts and the optimization of a photochemically-promoted radical reaction between these novel amino acids and various radical traps, particularly disulfides. In addition, this reactivity is extended to small molecule sulfinates and disulfide-containing peptides, for the development of an umpolung approach to the modification of cysteine residues. The thesis is divided into the following chapters: Chapter one summarises the existing literature on site-specific side-chain peptide modification, the development of the sulfinate moiety as a precursor for carbon centred radicals and the subsequent use of existing sulfinate reagents in the modification of small molecules and peptides. Furthermore, a brief history of photochemistry, focussing on the use of photochemistry as a tool for peptide modification, is discussed. The specific aims of this thesis are also outlined. Chapter two details the synthesis of the first amino acid sulfinate salts derived from the native hydroxy-functionalized amino acids hydroxyproline (HPro), homoserine (HSer) and serine (Ser), and summarises efforts towards the preparation of an amino acid sulfinate salt derived from threonine (Thr). Detailed optimization of the synthetic pathways are discussed. Chapter three focusses on the optimization and subsequent diversification of the amino acid sulfinate salts. Various mild oxidative conditions were probed for their effectiveness, including chemical oxidation, electrochemistry, and photochemistry. Optimization of key photochemical conditions enabled broad application to a functionally diverse array of disulfide radical traps. Chapter four aims to extend the reactivity of disulfides to a peptide context to investigate the feasibility of the reaction as a tool for the modification of cystine residues. Suitable peptide model systems were synthesized using solid phase peptide synthesis and small molecule sulfinates ('diversinates') are probed for reactivity with peptidic disulfides. Extensive optimization was conducted to improve reaction outcomes using high-throughput experimentation. This chapter also details the incorporation of amino acid sulfinates into a peptide as an alternative strategy for peptide modification. Chapter five summarises the advances made herein towards the development of sulfinate salts as tools for the modification of peptide substrates. Future directions are also discussed, including the incorporation of the amino acid sulfinates into peptides to enable to synthesis of biologically relevant peptides, such as the lanthipeptide family of natural products . In addition, the prospect of creating tuneable protected amino acid sulfinates for one pot modification techniques is discussed. Chapter six provides the detailed experimental protocols and characterization data for all compounds described in Chapters 2-4 of this thesis.
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Aseptic loosening around total hip and knee arthroplasty is linked to plasma microRNA
(2024) Deng, Yi
Total hip and knee joint replacement have revolutionised the way we treat end-stage degenerative joint diseases. However, aseptic loosening is still a major cause of prosthesis failure, leading to revision surgery. The pathophysiology of aseptic loosening begins with debris particles being generated as the implants wear over time. These microparticles cause osteolysis around the prosthesis, which begins to weaken the bony architecture over time, thus leading to loosening of the implant. However, this theory alone does not explain why certain patients have significant amounts of prosthesis wear, but very little osteolysis, whereas other patients have minimal prosthesis wear and significant osteolysis and aseptic loosening. Perhaps there is an underlying genetic predisposition that is regulated by pathways that places certain patients at a greater risk of osteolysis and aseptic loosening. One other possible explanation we must acknowledge could be an undetected infection, however this topic is beyond the scope of this thesis. MicroRNAs (miRNA) are well known for their ability to regulate gene expression in humans. They are present in all tissues and can be readily detectable in the blood stream and other bodily fluids contained within exosomes. Their use as biomarkers and master gene regulators have been documented widely in other fields of medicine and science, but very little research has been conducted on their role in orthopaedic surgery and arthroplasty. We hypothesise that there are differences in miRNA expression plasma of patients with aseptic loosening compared to control patients, and that these differences can be linked to bone metabolism leading to osteolysis and aseptic loosening. Our study investigated the potential regulatory roles miRNA have in the development of osteolysis and aseptic loosening around hip and knee arthroplasty. Firstly, a retrospective case-control study was conducted to identify clinical risk factors for aseptic loosening. Then a prospective case-control study was conducted to recruit patients undergoing revision surgery for aseptic loosening compared to control patients. Samples of bone, tissue and blood were collected for RNA-sequencing. RNA-sequencing was conducted on bone, tissue and plasma samples to identify differentially expressed RNA and miRNA genes related to bone metabolism and osteolysis. Matching was done using online databases do identify miRNA-mRNA target-expression pairs to understand regulatory mechanisms by which miRNA can regulate bone metabolism. Gene-expression and pathway analyses were performed to identify regulatory pathways of miRNA in the development of osteolysis and aseptic loosening. Western blotting was done on bone and tissue samples to validate our findings. Our sequencing results revealed several miRNA which were differentially expressed in the plasma of patients with aseptic loosening compared to controls. These miRNA all had several mRNA targets in the periprosthetic bone and tissue around the prosthesis. The potential pathways by which these regulate bone resorption are the Wnt and JAK-STAT pathways. Protein expression analyses confirm differences in protein expression are detectable at the molecular level in osteolytic bone samples. This is the first study to our knowledge investigating the role of circulating miRNA in patients with aseptic loosening around hip and knee replacements. These findings help us understand the pathophysiology of osteolysis and aseptic loosening. It adds to the growing body of knowledge of miRNA and may serve as a base for further research investigating the potential role as a biomarker or therapeutic target in the future.
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Negative Campaigning in Indonesia's Digital Era Elections
(2024) Simarmata, Salvatore
Negative campaigning can inform voters and ensure accountability, but it can also foster voter cynicism, divert attention from meaningful policy debates, and increase political polarization. In the digital era, negative campaigns have shifted from fostering informed discussion to employing manipulative tactics by focusing on the candidate's character, particularly issues of identity that have not been systematically investigated in Indonesian context. This thesis explores negative campaigning in the digital era in Indonesia marking the new wave of digital political communication by looking at its mechanics, actors, key narratives, and effects. To this end, the study analyses three elections: the 2019 presidential election, the 2022 mayoral election in Medan in Sumatra, and the 2022 mayoral election in South Tangerang in Java. Fieldwork for this thesis included conducting over two years of semi-structured interviews with key stakeholders, such as politicians and social media campaigners. In addition, content analysis was carried out on social media and other online media, as well as orchestrating various other surveys. The findings reveal that digital media has transformed the nature and professional practice of negative campaigning. Campaign actors, such as influencers and buzzers, operate covertly on various social media platforms, employing bots, automation, and anonymity to amplify messages, ranging from legitimate criticisms to slander and disinformation using computational propaganda. Key to this study is the identification of various negative campaign narratives, such as portraying opponents as disobedient to Islam, subservient to foreign interests, lacking integrity, or being associated with the Indonesian Communist Party. This thesis also highlights the impact of negative campaigning on voters, showing a feasible decrease in support for the targeted candidate. My key theoretical contribution to the literature lies in the cross-disciplinary integration of communication and politics in theories, methodologies, and argumentation, which significantly enriches the field of political communication research in recent time. My thesis found that negative campaigning is primarily dominated by character attacks that exploit the identity issues of candidates, rather than focusing on policies. The findings of this first systematic study with extensive case details in Indonesia enhance the understanding of computational propaganda in the world's fourth-largest democracy and highlight the need to mitigate their adverse effects. The findings also indicate the emergence of digital negative campaigning which is different from the old conception at the mass media era.
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Investigating how metabolite fluxes affect two brain diseases using different model systems
(2024) Gao, Xuexin
The work described in this thesis investigated the metabolite fluxes involved in two brain diseases, divided into two parts. Part A studied metabolite flux of ketone bodies in a glioblastoma cell line and compared with other cancer cell lines. Investigation of Part A concentrated at cellular level and the flux of ketone body metabolism was examined to illustrate how cells use ketone bodies for support of proliferation. The study was expected to tell us whether a ketogenic diet may be beneficial to glioblastoma treatment. Glioblastoma is an aggressive form of brain cancer, presenting significant challenges due to limited treatment options. While normal brain cells primarily utilise glucose for energy, they can adapt to alternative substrates such as ketone bodies. This study investigates whether different cancer cell lines retain the ability to utilise ketone bodies as energy substrates, with a focus on beta-hydroxybutyrate metabolism. The results revealed that all cell lines exhibited enhanced aerobic glycolysis, leading to lactate production in the presence of oxygen, with compensatory flux from glutamine metabolism into the TCA cycle. Supplementing beta-hydroxybutyrate did not promote the growth of any cell line, despite the expression of requisite transporters and enzymes. Beta-hydroxybutyrate contributed to metabolic flux into the TCA cycle for biomass and energy production; however, this pathway was significantly reduced in the glioblastoma cell line U-87 MG compared to the other cell lines. This finding suggests the potential efficacy of ketogenic diets as a treatment option for glioblastoma patients, providing additional energy substrates for normal cell metabolism. Furthermore, the U-87 MG cell line exhibited overexpression of the mitochondrial uncoupling protein UCP2 and distinct morphological changes in mitochondria, indicating a potential link between these factors and the reduced utilisation of beta-hydroxybutyrate through the TCA cycle. Further investigation is warranted to elucidate this relationship fully. Part B investigated the efflux of amyloid-beta peptides out of cells. Deposition of amyloid-beta peptides is one of the hallmarks of Alzheimer's disease and it may relate to an impaired clearance pathway with a critical actor: P-glycoprotein. This investigation focused on the organismal level and used C. elegans as a model organism for measuring behavioural effects. The expectation was to elucidate whether P-glycoprotein could be a target in the prevention of Alzheimer's disease. Alzheimer's disease poses a growing concern to society, particularly with the aging population. Current understanding implicates abnormal accumulation of amyloid-beta peptides as a key factor in its pathogenesis, potentially leading to neuronal dysfunction. Our observation indicated that the presence of amyloid-beta aggregates in the body wall muscles or somatic nervous system correlated with impaired locomotion, neuromuscular functions, and a shortened lifespan in C. elegans. A C. elegans strain with human P-glycoprotein expression in body wall muscles was made and used to generate a hybrid strain expressing both amyloid-beta and human P-glycoprotein. The expression of human P-glycoprotein in C. elegans caused paralysis and compromised neuromuclular functions in the worms, but the lifespan was unaffected. Although human P-glycoprotein expression did not reduce the accumulation of amyloid-beta peptides in worms, it restored locomotion compared to parental strains expressing amyloid-beta or human P-glycoprotein alone. The restoration of locomotion did not translate into improvements in neuromuscular function or lifespan. The results suggest that targeting the P-glycoprotein-mediated clearance pathway holds promise for preventing Alzheimer's disease. However, it also highlights the complexity of the clearance pathway, indicating that multiple components may be considered for effective therapeutic strategy.
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Naphthyridine-derived bimetallic phosphinite and metallophosphorane complexes
(2024) Delaney, Andie
The studies presented here concern the synthesis and reactivity of bimetallic phosphinite and metallophosphorane complexes. Much of the work presented is on the synthesis of bimetallic complexes using new dinucleating ligands, sometimes using a dehydrohalogenation methodology that has not yet seen much use in the synthesis of bimetallic complexes. The synthesis of Group 10 and 11 metal complexes are presented, with a major focus on the reactivity and catalytic potential of bimetallic complexes of nickel and palladium. Dinucleating "expanded pincer" ligands have previously been used to isolate bimetallic complexes. To add to this body of literature, the first publication presents the synthesis of bimetallic gold(I), silver(I) and copper(I) complexes of the tBuPONNOP ligand, a new expanded pincer ligand based on a 2,7-diphosphinite-substituted-1,8-naphthyridine backbone. A range of coordination modes were observed, with the geometric preference of the transition metal determining if it binds through P,N-, P,P- or P-only coordination modes. However, the low-yielding synthesis of the tBuPONNOP ligand hampered further research into this ligand. The second publication studies the tendency of the tBuPONNOP ligand to rearrange in the presence of NiBr2, which was observed previously for iPrPONNOP. However, a new rearrangement product was accessible with tBuPONNOP; the bimetallic metallophosphorane complex Ni2Br2(tBuPONNOPONNO), which featured formation of a new P-O bond to give a diphosphoranide ligand. Phosphoranides have not previously been incorporated into dinucleating ligand frameworks. New precursors, PONNHO, were developed to access PONNOPONNO products more easily, but the tBuPONNHO and iPrPONNHO precursors were found to give different product distributions. The dinickel(II) complexes Ni2Br2(PONNOPONNO) could be reduced to form highly planar dinickel(I) species, Ni2(PONNOPONNO), which have a direct Ni-Ni bond. While elementary reaction steps are well-understood for monometallic systems, there have been less studies on how bimetallic complexes perform these transformations. The third publication focuses on the reactivity of Ni2(tBuPONNOPONNO) with alkyl halides in order to explore elementary steps. Oxidative addition occurs across the Ni-Ni bond to form species of the type Ni2(R)(X)(tBuPONNOPONNO). However, the ethyl-bridged species are unstable in solution, undergoing beta-hydride elimination to form ethene and Ni2(H)(X)(tBuPONNOPONNO). DFT studies were used to examine the mechanism of beta-hydride elimination, representing one of few mechanistic studies into this step for dinuclear complexes. The macrocyclic structure of the ligand was found to have a major impact on the rate of beta-hydride elimination, with the bending of the backbone in the absence of a coordinating anion reducing the rate by relieving steric pressure on the bridging ethyl ligand. Unpublished reactivity studies are discussed to show the difficulty in understanding the mechanism of oxidative addition to Ni2(tBuPONNOPONNO). The fourth publication explores the use of PONNHO ligands to access bimetallic palladium and platinum complexes via dehydrohalogenation. In this case, monometallic MCl2(PONNHO) complexes could be isolated, which were not observed during studies with nickel. Addition of a base to MCl2(tBuPONNHO) gave bimetallic species of the type M2Cl2(tBuPONNO)2, and these M(II)2 complexes could be reduced to give species with Pd(I)-Pd(I) and Pt(I)-Pt(I) bonds of the form M2(tBuPONNO)2. Interestingly, the macrocyclic diphosphoranide PONNOPONNO ligand does not form when using Pd or Pt precursors. Instead, a weak P-O interaction, of which there have been few reports for transition metal complexes, is apparent from solid-state and solution-state data of M2(tBuPONNO)2. Finally, the catalytic potential of Ni2Br2(PONNOPONNO) and Pd2Cl2(tBuPONNO)2 in cross-coupling was examined. These studies are ongoing.
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Characterisation of MlaD from Acinetobacter baumannii
(2024) Zhang, Jing
Acinetobacter baumannii (Ab) is a clinically important pathogen that has rapidly developed resistance to many antibiotics. The outer membrane of A. baumannii (and other Gram-negative pathogens) plays a crucial role in intrinsic antibiotic resistance. The Maintenance of Lipid Asymmetry (Mla) transporter is essential for maintaining the integrity of the outer membrane in all Gram-negative bacteria through the transport of phospholipids. The Mla transporter contains six components, including the inner membrane MlaFEDB complex, periplasmic MlaC, and MlaA which is embedded in the inner leaflet of the outer membrane. MlaC is proposed to shuttle phospholipids between the outer and inner membranes through interactions with MlaA and MlaD, respectively. Bioinformatics analysis revealed that AbMlaD contains a novel mammalian cell entry (Mce) domain with a unique 47 amino acid (aa) additional region, which is highly conserved within Acinetobacter species, but not found in any other MlaD orthologs. This current study investigated the structure and function of AbMlaD, including that of the 47-aa additional region. The crystal structure of the soluble domain of AbMlaD, solved at 2 Angstrom resolution, revealed a conserved seven-stranded beta-barrel fold connected by loops, with the 47-aa additional region forming a helix-turn-helix structure between the fourth and fifth beta-strands. Similar to EcMlaD, six AbMlaD monomers are assembled into a homo-hexameric ring structure, and the 47-aa additional region (of each monomer) is found on the exterior of the hexameric ring, protruding from the inner membrane into the periplasm. This study employed a combination of in silico, biochemical, and biophysical analyses to investigate the functional role of the AbMlaD 47- aa additional region. A thermal shift assay, a tryptophan quenching assay, and thin layer chromatography were used to assess the interaction between AbMlaC and AbMlaD or an AbMlaD derivative lacking the 47-aa additional region, as well as the efficiency of phospholipid transfer. In vitro results demonstrated that the 47-aa additional region strengthens the interaction between AbMlaD and AbMlaC, promotes phospholipid transfer from AbMlaC to AbMlaD, and stabilises the AbMlaD hexamer. However, the additional region was not required for maintaining outer membrane integrity or for forming a complex with other Mla inner membrane components. In addition to their role in phospholipid transport and membrane homeostasis, Mla transporter components have been linked to the virulence of various pathogens. This study investigated the role of MlaD in the pathogenicity and survival of the multidrug-resistant A. baumannii strain BAA-1605. A markerless deletion method was used to construct a BAA-1605 mlaD deletion mutant, which was characterised phenotypically and complemented to validate the direct involvement of MlaD (and the 47-aa additional region) in the observed phenotypes. Deletion of mlaD led to a compromised outer membrane, a growth defect under static conditions, decreased biofilm formation, decreased ability to kill eukaryotic cells, and attenuated virulence in a murine model of A. baumannii infection. The 47-aa additional region of AbMlaD did not play a role in these pathogenetic traits. This study increases our understanding of the structure and function of MlaD, and by extension, the Mla transporter, as well as their role in A. baumannii pathogenesis. The insights gained through this work pave the way for inhibition studies to ascertain the likelihood of being able to inhibit or modulate the Mla transporter with a small molecule drug, and in doing so, reduce A. baumannii virulence.
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Psi controls signalling from the Drosophila cortex glial niche to regulate neural stem cell fate
(2024) Muckle, Damien
Glioma patients experience high rates of morbidity and invariable fatality, yet no new, effective treatments have emerged in more than 35 years. Progress in therapeutic development is hindered by a limited understanding of the biology of these heterogeneous brain tumours, which are driven by glioma stem cells supported by a glial niche. Genomic sequencing of the low-grade brain tumour oligodendroglioma identified frequent loss-of-function mutations in the single-stranded DNA/RNA binding protein FUBP1, which are predicted to drive these tumours. However, functional studies investigating FUBP1 function in mammalian systems are complicated by compensatory effects from paralogues within the FUBP protein family, which share common gene binding targets. In Drosophila, the three mammalian FUBP proteins are represented by a single orthologue, Psi, which shares high structural and functional similarity to FUBP1. By taking advantage of this reduced functional redundancy, and the powerful tractability of Drosophila genetics, we dissect FUBP1/Psi function in the cortex glial niche, which functions analogously to the oligodendroglioma niche by providing the structural support and secreted signals which regulate stem cell proliferation and differentiation. Here we demonstrate Psi knockdown specifically in the cortex glial niche of the Drosophila larval brain reduces cortex glial growth and proliferation. Moreover, cortex glial-specific Psi depletion cell non-autonomously drives the proliferation and expansion of otherwise wild-type NSCs. Thus, we present the first evidence that an FUBP family protein functions in a cell non-autonomous manner to control NSC fate. To determine the molecular basis for Psi's capacity to control NSC renewal and differentiation from the supporting cortex glial niche, we used Targeted DamID (TaDa) to identify direct, genome-wide Psi binding targets in cortex glia. We further identified differentially expressed and/or spliced targets via RNA sequencing of Psi-depleted cortex glia and associated NSCs compared with isogenic controls. Intersection of Psi binding targets and transcriptionally altered genes in Psi-depleted cortex glia revealed Psi directly regulates components of major developmental signalling pathways, Hippo and MAPK, among other networks essential for niche function. Our functional genetic studies indicate Psi represses upstream Hippo pathway components in the niche to maintain normal cortex glia growth and proliferation. Furthermore, Psi knockdown directly upregulates EGFR ligand spitz (spi) in cortex glia, which functions in the niche to cell-autonomously regulate cortex glia growth and proliferation. Psi depletion also upregulates another EGFR ligand, gurken (grk), which, in contrast to spi, is required to enable expansion and proliferation of neighbouring NSCs driven cell non-autonomously by loss of Psi. Together, our data demonstrate Psi functions cell non-autonomously in the glial niche to orchestrate signalling networks required to prevent excessive NSC renewal. Thus, given the high degree of functional homology with Psi, we predict FUBP1 loss-of-function drives oligodendroglioma tumourigenesis, at least in part, by dysregulating intra-tumour interactions between the glial niche and glioma stem cells.
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International politics and construction of climate security by small island developing states: Maldives and Samoa form broader meanings of security
(2024) Rasheed, Athaulla
This research investigates Small Island Developing States' (SIDS) discursive formation of national and foreign policy narratives on climate change as a security concern. It recognises SIDS have played an important role in promoting comprehensive approaches to climate security at the United Nations Security Council debates - these included considering multi-sectoral climate-related threat factors and comprehensive security provisions, including collaborative (whole-of-government) governance approaches to address them. For this thesis, climate security is defined as the ability of states or communities to address and build resilience against climate change in achieving sustainable development, self-sufficiency, and national security. Although it recognising SIDS' engagements in the Security Council debates, the main objective of this thesis is not to analyse their international (climate security) narratives, but instead to present an analytical framework to investigate and portray a domestic construction of climate security by SIDS - using the Maldives' and Samoa's experience - and to explain the domestic narratives driving these countries' national and foreign policy on climate change as a security issue. This thesis asserts that domestic construction helps to make better sense of why SIDS' claim for broader meanings of security becomes important for the Security Council's climate debates, or securitising climate at the international level, and why a comprehensive approach to problem-solving is important in addressing the impacts of climate change on national and international peace and security. In this respect, in adopting a constructivist approach to international relations and security studies, this thesis identifies, analyses, and explains the discourses and identities constitutive of policy narratives that have shaped the climate threat identification and problem-solving approaches adopted in Maldives and Samoa. This thesis analyses the formation of climate policy as a national crisis, threat categories impacting the countries' capacity to achieve sustainable development, and the meaning of security in their island contexts concerning those threats. In that, the intersubjective aspect of the discursive formation of identities and interests explains the interconnectedness or constitutive function of domestic and international policy narratives of states. The domestic interests associated with policy narratives concerning the security implications of climate change can explain both their national and foreign policy drivers. This thesis concludes that the Maldives' and Samoa's cases assert that SIDS become important stakeholders in developing intersubjective narratives to incorporate more holistic and comprehensive aspects of problem-solving into the international peace and security discourse concerning climate change. The Maldives' and Samoa's policy discourses and identities forming climate security narratives, analysed in this thesis, provide a practical framework to explain this.
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Appropriately Timing Seed Germination- New Players and Upstream Controllers
(2024) Wellawatta Mudiyanselage, Ayesha
Seed germination is a most critical developmental phase change, particularly under abiotic stress conditions such as drought or salinity. The timing of germination plays a major role in setting the timeline of the plant developmental cycle, and in conditioning seedling survival and adaption to unfavourable environments until completion of the plant developmental cycle and successful reproduction. Over recent decades, great progress has been made in understanding seed dormancy, its establishment during maturation on the mother plant, and the factors controlling its release after shedding. In contrast, little is known about the genetic determinants of germination in non-dormant seeds, especially under abiotic stresses. The Arabidopsis ERECTA family AtERf is demonstrated master regulator of various aspects of aerial plant growth and development, and is also involved in responses to environmental stresses, and some immune responses. A recent study (Nanda et al., 2019) uncovered another, unsuspected function, especially in the sensitivity of seed germination to salinity and osmotic stress. The germination of seeds with reduced ERECTA family signalling was found to slowed down, delayed or even halted by salinity and osmotic stress, through largely reversible mechanisms, so that when conditions became more favourable again, germination generally resumed, without significant loss of seed viability. That adaptive function was shown to be primarily under maternal control, and to involve the three family members, with specificity, among ERf members. The present study followed from that work, with a two-fold aim: a) Better understand the physiological and molecular bases of the maternal inheritance of the ERf-mediated germination phenotype; b) Test conservation across species of the newly discovered ERf regulatory function in Arabidopsis seed germination, with a focus on barley (Hordeum vulgare, Hv), a major staple food and pillar of the brewing industry. The first Chapter of this thesis describes the discovery of a novel molecular interactor of the Arabidopsis AtERf - the MYB family transcription factor AtGL1- previously unknown to be acting in seeds, nor to interact with the extensively documented ERf signalling pathways in aerial organs. GL1 is here shown to synergistically interact with the ERf members, in a gene combination-dependent manner, to regulate the initiation, progression, and timing of germination completion under saline conditions. A second Chapter reports on a genome-wide analysis of ERf- and GL1-mediated changes in transcriptional networks during early seed development and differentiation through RNAseq analysis of developing siliques. The results indicate that wide-spread ERf and GL1 separately act and also interact in the transcriptional control of hormone signalling, transcription factors, cell wall biogenesis, the formation of cuticular and wax compounds, stress response pathways. The last part of the thesis presents the analysis of a range of barley mutant lines obtained through CRISPR-Cas9 editing of the putative barley HvERf and HvGL1 orthologues. They show that these genes, separately and together, exert a major regulatory role in vegetative development, fertility and the anatomical and structural characteristics of the maternal seed enclosing tissues, and in the regulation of seed germination under salinity but also constitutively. In conclusion, the findings reported in this thesis overall highlight the potential of the barley ERECTA genes and putative orthologue to AtGL1 for genetic improvement, especially with respect of more uniform germination within seed cohorts, and regulation of its timing to mitigate risks of germination failure or seedling death, thus enhancing yield.
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A Change In The Field: Australia-India cricket and the possibilities for cultural openness in the shadow of colonialism
(2024) Piggott, Geoffrey
A common view in the discourse of Australia-India cultural relations is that for a more meaningful relationship to develop, Australia must move beyond approaching India through the prism of practices which have their roots in the two countries' shared - but contrasting - history of British colonialism. Cricket, it is often said, provides a shallow point of connection and acts as a reminder of the racial and cultural injustices of Empire. This thesis problematises such received wisdom. It begins from the premise that while there is little doubt that a colonial lens limits Australian understandings of India, cricket continues to be a major point of popular cultural contact between the two countries, and has, in the last three decades, moved beyond the colonial power dynamics of its past as India has become the pre-eminent force in the sport. In light of this, this thesis asks how and to what extent cricket might move Australia-India cultural relations beyond their mediation through the echoes of the British Empire and foster a disposition of greater cultural openness from Australia towards India. It presents a detailed study of media representations and in-depth interviews with commentators, journalists, administrators and players, examining how India's rise to power in cricket was negotiated in Australia. Through analysis of a series of ruptures in the sport during the late 1990s and early 2000s, the thesis charts how long-maintained Australian narratives of Indian racial and cultural inferiority were rendered unsustainable by India's exercise of its newfound power. This was due, I argue, partly to the specificities of sport as a cultural field, its lusory nature providing space for changes in Australian attitudes, and partly to the impact, in Bourdieuan terms, of the economic field on the cultural, with India's economic power changing fundamental aspects of the form of the sport. The shift in cultural power opened new possibilities and posed still unresolved challenges for Australian cricket and the broader Australia-India cultural relationship. On one hand, the period of conflict, ironically, established a site of nostalgic memory which now provides a meaningful point of connection between the two countries. On the other hand, the changes in the form of the game mean that cricketing traditions which have positioned it as part of the Australian national imaginary are threatened, and that the financial health of the sport is tied to a hyper-commercial and increasingly politicised Indian cricket establishment. Through my research, in addition to adding to the discourse of Australia-India relations, I add to contemporary debate in cultural studies and postcolonial studies. I propose that, for all the game's colonial history and contemporary neo-liberal capitalist logic, the changes in cricket are an example of how formerly colonial cultural practices can, in complex and imperfect ways, move beyond their racially hierarchical histories, act as a shared point of reference across national-cultural boundaries and provide a site for the development of attitudes of cultural openness.
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Additive Manufacturing Based on Electrochemistry
(2024) Viktorova, Jekaterina
A fabrication method combining 3D printing and multi-material electrodeposition is introduced in this thesis. The method combines electrochemical and three-dimensional control of electrode positions to culminate in a new process for 2D patterning and the 3D printing of metals, semiconductors, as well as polymers into complex shapes with feature sizes as small as 10 um. The method specifically allows access to patterned or printed, previously difficult-to-process electrically conductive pi-conjugated polymers. The technique uses electrodes in a solution of an electrodepositable material to perform electrochemical printing, a process that can be controlled by varying the inter-electrode gap, the applied potential or current, the electrode geometry and dimension, the electrodeposition solution (ink), movement direction, and movement speed. The first chapter introduces the concepts of electrodeposition and localized electrodeposition and applies them to electrochemical printing. It also explores the influence of the different parameters which affect the printing process and introduces the types of materials that can be printed using this method. In Chapter 2, electrochemical printing is shown to have a unique combination of speed and resolution, multi-material printing, and morphology control, culminating in multi-material device fabrication. In Chapter 3, the first steps are made in monitoring the electrochemical reactions and localized deposition processes in-situ by combining electrochemical analytical methods such as cyclic voltammetry and chronoamperometry with electrochemical quartz crystal microgravimetry. Using poly(3,4-ethylenedioxythiophene) (PEDOT) as a model system, we study the effects that the composition of the supporting electrolyte and solvent used, de-oxygenation and monomer concentration had on the polymerization yield. In Chapter 4, a brand-new approach involving the ferrocene-mediated cationic electrochemical printing of bisphenol A diglycidyl ether and tris[4-hydroxyphenyl] methane triglycidyl ether) based on electrochemically controlled ring-opening polymerization is demonstrated. The development of this novel fabrication method combining 3D printing and multi-material electrodeposition opens new pathways for advanced material design and manufacturing. By enabling precise, controlled deposition of metals, semiconductors, and conductive polymers in complex 2D and 3D architectures, this technique can significantly enhance applications in fields such as flexible electronics, biosensors, and energy storage devices. The ability to pattern previously hard-to-process conductive polymers also presents opportunities for innovations in organic electronics and optoelectronic devices. The versatility and scalability of this method position it as a promising platform for future research and development in multi-material printing and electrochemical manufacturing, potentially unlocking the production of functional materials and devices.
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Characterisation of the Transcriptome and Proteome of Residual Bodies and Uncovering of a Non-Canonical Role of the Histone Variant H2A.B3 During Spermatogenesis
(2024) Apu, Nazmul
Spermatogenesis is a process where male germ cells undergo morphological changes to become motile and fertile spermatozoa. Key changes include the shrinkage of the nucleus, development of the flagellum, and extrusion of most cytoplasmic contents into the lumen of the seminiferous tubules in the form of Residual Bodies (RBs). Conventionally, RBs were thought to be phagocytosed by Sertoli cells (SCs). However, recent evidence challenges this view, highlighting a more intricate utilisation of RB contents. Specifically, H2A.B3, a spermatid-specific histone variant known for its positive regulation of germ cell transcription, is preserved in a full-length non-chromatin-bound form within RBs. Remarkably, upon RB absorption, H2A.B3 is detected in the nucleus of SCs. Intriguingly, the H2A.B3 KO mouse exhibits tubules congested with the cytoplasmic content of maturing spermatids and defective SC phenotypes. This suggests a novel epigenetic information transfer mechanism between germ and Sertoli cells mediated by RBs, where H2A.B3 potentially acts as a chaperone to transport germ cell-specific factors to SCs. The first aim of the thesis was to establish an improved purification method for RBs from mouse seminiferous tubules. Chapter 3 introduces a continuous sucrose gradient ultracentrifugation-based method, enabling the isolation of up to 98% pure RBs from only 1 g of testis tissue. Morphological characterisation of RBs using RB-specific EMA staining and transmission electron microscopy (TEM) revealed that the tubules of H2A.B3 KO mice contain a more dispersed form of RBs with a different size distribution, suggesting delayed RB absorption by SCs and slower tubule differentiation. Furthermore, H2A.B3 KO RBs demonstrated more filled vacuoles of lysosomal nature compared to WT, implying defects in lysosomal clearance. The second aim, explored in Chapters 4 and 5, was to comprehensively characterise the transcriptome and proteome of RBs, respectively. Using Nanopore RNA-sequencing (RNA-seq), diverse classes of biologically important RNA were identified in RBs, with a significant overrepresentation of replication-dependent histone genes in H2A.B3 KO RBs. This implies a defective chromatin compaction process, as evidenced by a higher sperm chromatin density in H2A.B3 KO mice. Additionally, H2A.B3 was found to be involved in splicing, showing a preference for first and last exon inclusion. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) proteomic study of RBs detected 3,226 proteins, which are mainly involved in protein transport and metabolism. Our investigation also reported the presence several histone proteins in RBs for the first time. Moreover, RBs contain nine unique H2A.B3-interacting proteins, the majority of which are associated with splicing. The third aim of the thesis, explored in Chapter 6, was to investigate the role of H2A.B3 in RNA degradation. A newly developed bioinformatic pipeline was used to measure and compare the 3'- and 5'-end degradation levels of replication-dependent histone mRNA transcripts between WT and H2A.B3 KO across various spermatid stages and RBs. The 3'-end of replication-dependent histone mRNAs was the most degraded in early-round spermatids of H2A.B3 KO mice, whereas the 5'-end remained mostly unaffected, which was also validated by overexpressing the H2A.B3 protein in Neuro2a cells. In summary, this thesis presents a modernised RB purification method, aiding in understanding RB biology and the crucial roles played by H2A.B3. The findings lay the groundwork for investigating broader hypothesis regarding epigenetic information transfer between germ cells and SCs via RBs. Additionally, a novel non-canonical role of H2A.B3 in the degradation process of replication-dependent histone mRNA is uncovered, further expanding our understanding of spermatogenesis.
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In Situ Oxygen Isotopes and Water Concentrations: Analytical Developments and Applications to Extraterrestrial Materials
(2024) Patkar, Aditya
O-isotopes of chondrules, CAIs, and matrix commonly show variable 16O abundances. A 16O-poor aqueous or water-ice reservoir is thought to have influenced their primary isotope ratios. This study explores the interrelationship between O-isotope systematics and total water contents (H+OH+H2O) in components from carbonaceous chondrites, pallasites and asteroid Ryugu samples using the SHRIMP SI ion microprobe. Analytical development is needed to measure in situ water in meteoritic NAMs, and three O-isotopes in the hydrated chondrite matrix because of the presence of a large 16O1H peak. Techniques were developed to reduce instrument water background and reliably measure water content <100 ppm, employing various sample preparation methods and introducing a Bi-Sn alloy as an alternative to In mounts. Terrestrial minerals with varying water contents were used to quantify the tailing from 16O1H under the 17O peak. Minerals show D17O residuals systematically related to the 16O1H peaks suggesting consistent tailing, and a tailing correction has been proposed. Thirdly, IMF bias was determined in a suite of olivine reference materials over the entire Mg/Fe compositional range. CC chondrules show variable O-isotope ratios with most type I olivine (Mg#>90) are isotopically lighter reflecting reducing conditions, higher T, and lower dust:gas, whereas type II olivine (Mg#<90) that formed in an oxidising, dust-rich environment are isotopically heavier. In contrast to previous studies in chondrule NAMs with a large range of ~8 ppm to ~1 wt% water, our results in >250 olivine grains from chondrules and isolated matrix grains are much lower. Similar to O-isotope dichotomy, forsterites (Mg# >98) from CM, CO, CV chondrites contain a median of 4.6 +- 3.7 (1SD) ppm water, while type II olivine (4450 permil. However, CAI phases from CV finds show several 1000s of ppm water, potentially originating from small fractures that pervade the CAIs, especially melilite, suggesting terrestrial alteration. Lower water in clean regions of melilite from CV chondrite finds and in the rejected spots from Allende CAIs that overlap fractures suggests that the fractures from CV finds may contain localised incipient hydrated products. The low water data in Allende CAI phases suggests a nebular origin and similar P-T conditions which is consistent with our current understanding of CAI formation and evolution. Hydrated matrix from CM, CI, CY chondrites and asteroid Ryugu reflects extensive aqueous alteration. Bulk O-isotope ratios in the hydrated matrix dominated by serpentine-saponite show large IMF effects likely controlled by Mg/Fe variations. Bulk CM2 matrix shows D17O values ranging from -1.6 to -2.5 permil compared to whole-rock values which range between -2 to -4 permil. In contrast, matrix from CI and CY chondrites and Ryugu shows a D17O range overlapping with the whole-rock values. The large D17O scatter can be partly attributed to uncertainty in tailing correction but also possibly reflects the intrinsic isotopic heterogeneity of the chondritic matrix.
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Wild Goose Tracks in the Snow: An Illustrated Record of my Preordained Life by Wanyan Linqing (1791-1846): a nineteenth-century memoir
(2024) Sanderson, Christina
Wanyan Linqing (1791-1846) was a Manchu Bannerman who travelled throughout China as an official in service of the Qing Court. In his later years he acquired and moved into a renowned garden-mansion in Peking, where he composed an autobiographical memoir in classical Chinese, Hongxue yinyuan tuji (Wild Goose Tracks in the Snow: An Illustrated Record of my Preordained Life), recording, in two hundred and forty chapters each accompanied by a woodblock illustration, as many moments of his life deemed to have been the most memorable. During the 1980s, the first one hundred and seventy chapters of this memoir were translated and annotated in Hong Kong by Mongol Bannerman Professor Yang Tsung-han (1901-1992). Under the guidance of Professor John Minford, Christina Sanderson has recently compiled the first complete translation and annotation of this work, by editing Yang's existing translation and commentary and translating and annotating the final seventy chapters. This thesis is a reflection on that memoir, and on the process of its translation. It argues that Tracks in the Snow is a remarkable window into the world of traditional China. To prove this, it presents several different ways of reading the memoir, including from a biographical and historical perspective, and in the context of literature.
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Road from Rebetiko: Explorations in the Fusion of Jazz and Traditional Greek Urban Music
(2024) Campbell, Constantine Robert
This project is a research-led hybridity experiment in creative practice, fusing jazz and Greek rebetiko. The thesis explores the history and nature of jazz fusion - or hybridity - with a view to understand its significance for the genre of jazz and to position the rebetiko-jazz fusion experiment within it. The thesis also explores the history and nature of Greek rebetiko music in order to pay homage to its traditions, heritage, and musicians, and to embrace its spirit and learn from its mechanisms for the purpose of hybridity. Finally, the thesis offers an exegesis of creative practice, which describes the inspiration, methods, processes, and outcomes of this rebetiko-jazz fusion experiment, which culminates in twelve original compositions that have been performed and recorded across two albums. I conclude that my creative practice is a glocalised expression of both jazz and rebetiko.

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