Faculty of Science 2

Doctor of Philosophy

ABBASABADI, Mahsa

Thesis Title

Microbial Colonisation of Low-Quality Fodders in the Bovine Rumen

Supervisors

• Dr Kevin John Dudley  (Associate Supervisor)
• Dr Karen Harper  (External Supervisor)
• Associate Professor Mark David Harrison  (Principal Supervisor)
• Professor Ian Mark O'Hara  (Associate Supervisor)
• Adjunct Associate Professor Valentino Setoa Junior Te'o  (Associate Supervisor)

Citation

Sugarcane bagasse has a recalcitrant structure and is considered low-quality fodder. This thesis used thermochemical processes to convert sugarcane bagasse intonutritionally enhanced animal feed. Thermochemical treatments were developed at pilot scale to destruct bagasse structure and improve its digestibility. The digestibility andmicrobial colonisation of untreated and treated sugarcane bagasse samples were evaluated in the bovine rumen. Alkaline thermochemical treatment improved the digestibilityof bagasse and changed the microbial communities that were involved in the degradation of bagasse in the bovine rumen. This study provides new insights intothermochemical conversion of low-quality fodders to nutritionally enhanced animal feed.

ADAMS, Johnathan Alexander

Thesis Title

Mathematical Modelling of Person-to-Person Opinion Exchange: Understanding and Quantifying Polarisation

Supervisors

• Dr Robyn Patrice Araujo  (Associate Supervisor)
• Dr Gentry Adair White  (Principal Supervisor)

Citation

For most of human history, societies separated themselves based on their beliefs or opinions. We share our opinion with others in our social network. To understand how or why polarisation occurs, mathematical models of opinion exchange were developed. But early attempts at modelling opinion sharing demonstrated a bias towards consensus rather than polarisation. This thesis seeks to investigate polarisation. Methods were developed to determine the level of polarisation as were models that simulated the individual opinion exchanges that produce polarisation. All models developed were empirically tested.

AGUIAR ROCHA, Raquel

Thesis Title

Integrated Enzyme and Cofactor Engineering in Continuous Flow Biocatalysis

Supervisors

• Dr Laura Navone  (Associate Supervisor)
• Dr Colin Scott  (External Supervisor)
• Adjunct Professor Robert Edward Speight  (Principal Supervisor)

Citation

This thesis discusses two major aspects involved in the transition of biocatalysis from simple batch operation to spatially and temporally compartmentalised continuous flowsystems. To support this transition, engineering of enzymes and cofactors is essential. In this research, enzyme engineering for the preparation of immobilised enzymes wasexplored. Enzymes were genetically fused to non-covalent affinity tags and immobilised on low-cost carriers for application in flow assisted biocatalytic protocols. In addition,novel nicotinamide cofactor biomimetics that may allow cofactor tethering were prepared to support implementation of cost-effective cofactor-dependent redox biocatalyticmethodologies.

ALKENANI, Ahmed Hassan A

Thesis Title

Deep Discourse Analysis for Early Prediction of Multi-Type Dementia

Supervisors

• Professor Yuefeng Li  (Principal Supervisor)
• Associate Professor Yue Xu  (Associate Supervisor)
• Dr Qing Zhang  (External Supervisor)

Citation

Dementia is a major debilitating progressive and irreversible disorder that has no cure at present. The importance of automating dementia screening towards facilitating its early prediction has long been emphasized, hampered in part by lack of empirical support. Motivated by the evident language deficiency in the onset of dementia, this thesis proposes and presents a collection of methodologies that lead to robust diagnostic models for multi-type dementia through discourse analysis. Given their high performance, these diagnostic models provide a substantial contribution to the underlying task of effective dementia classification needed for the development of automated pre-screenings tools for dementia syndromes.

AMBE, Aloha May Hufana

Thesis Title

From Monitoring to Engagement: Co-Designing Future Technologies with Older Adults

Supervisors

• Professor Margot Brereton  (Principal Supervisor)
• Adjunct Professor Elinor Laurie Refsland Buys  (Associate Supervisor)
• Professor Paul Roe  (Associate Supervisor)
• Associate Professor Alessandro Soro  (Associate Supervisor)

Citation

Monitoring technology solutions for older people’s independent living tends to treat them as passive recipients of technology to be observed by others. This thesis investigatedolder people’s perspectives, exploring how they might reimagine these technologies in their life and future, by involving them in co-design and qualitative research. Studiesincluded older adults inventing their own Internet of Things with kits, writing fictional works about life with future technology, and trialling a collaborative “messaging kettle”. Thisthesis proposes a design approach that shifts the emphasis from perceived needs to bring to light the lived values, agency and aspirations of older people.

APPUKUTTAN KURUP, Lekshmi

Thesis Title

Graphene Porous Foam Capacitive Pressure Sensors for Low Pressure Sensing Applications

Supervisors

• Adjunct Associate Professor Kateryna Bazaka  (External Supervisor)
• Professor Nunzio Motta  (Associate Supervisor)
• Associate Professor Soniya Devi Yambem  (Principal Supervisor)

Citation

There exist many reports on capacitive pressure sensors based on porous foams due to their outstanding performance features. However, the structure-property relationship of the foam and its influence on boosting the sensitivity of the pressure sensor needs to be further explored. This thesis is a comprehensive study of graphene-PDMS foams used for capacitive pressure sensing for low pressure applications. The study showed that capacitive pressure sensors with graphene-coated foams had the highest sensitivity. Further, inclusion of small pores increased the sensitivity as well as linearity of sensitivity.

AUSTIN, Joseph Martin

Thesis Title

Testing the `Terrane-Boundary' Concept and Geodynamics in the NeoArchean: A Case Study of the Stratigraphy from the West and East Laverton Greenstone Belts

Supervisors

• Dr Patrick Calder Hayman  (Principal Supervisor)
• Dr David Thomas Murphy  (Associate Supervisor)

Citation

This thesis tests the geodynamic models thought to occur on the early Earth more than 2.7 billion years ago (Ga), and has implications for mineral exploration. Extensive fielddata, combined with lab-based studies, were used to reconstruct a geological event history and test correlations across a contentious tectonic structure (Hootanui Shear Zone,HSZ) in the Laverton Greenstone Belt (Yilgarn Craton, Western Australia). The results of this work indicate that the HSZ represents rift architecture and supports a craton-widelink for the 3.02 – 2.71 Ga time interval, during which the crust underwent modification largely by vertical tectonic processes.

BACHMANN, Julian

Thesis Title

Mechanistic Investigations of On-Demand Light Degradable Polymeric Materials

Supervisors

• Distinguished Professor Christopher Winfried Barner-Kowollik  (Principal Supervisor)
• Associate Professor James Peter Blinco  (Associate Supervisor)
• Dr Charlotte Philippine Petit  (Associate Supervisor)
• Dr Andreas-Neil Unterreiner  (External Supervisor)

Citation

Polymers (colloquially called ‘plastics’) are a unique material class. They critically influenced many aspects of society thanks to their characteristics. Ideally, degradation is desired after usage, but polymers usually lack the feature of ‘on-demand’ degradability. Light would be an ideal trigger medium, given its abundance and control in space and time, thus constituting a suitable stimulus to induce degradation on-demand. In the present thesis, the trigger ‘light’ was explored to provide a powerful tool for on demand degradation scenarios. For this purpose, several polymer model systems were selected, their mechanism of action investigated in detail and probed for degradability.

BALASURIYA, Jayaran Kaduge Saminda Sundeepa

Thesis Title

Identifying and Integrating Diverse Roles of Stakeholders for Co-design of Technology in Disability Support Context

Supervisors

• Professor Margot Brereton  (Associate Supervisor)
• Dr David John Ireland  (External Supervisor)
• Associate Professor Laurianne Julie Sitbon  (Principal Supervisor)

Citation

Investigating how people with intellectual disability and people in their support network can be involved in the design and introduction of technology in the context of disabilityday centres. This research explored the interdependent relationship between people with intellectual disability and support workers and how this relates to technology use. Theimportance of the different roles that support workers play and the corresponding values related to those roles were identified. The Role-based Co-design method wasdeveloped to iteratively integrate the values of different stakeholders into the design of technology for use at disability day centres.

BROWNING, Raiha Tui Taura

Thesis Title

Bayesian Approaches for Modelling Discrete-Time Self-Exciting Processes and Their Applications

Supervisors

• Distinguished Professor Kerrie Lee Mengersen  (Principal Supervisor)
• Professor Judith Rousseau  (External Supervisor)
• Dr Gentry Adair White  (Associate Supervisor)

Citation

A Hawkes process is a temporal, self-exciting point process, such that events in the process may trigger future events, however, flexible representations of them areunderstudied. This thesis develops and applies new statistical methods for modelling multivariate, discrete-time Hawkes processes using flexible Bayesian statistics.Spatiotemporal variants of discrete-time Hawkes processes are also studied. These models are applied to two substantive case studies. The first case study is concerned withdescribing the spread of the novel coronavirus COVID-19. The second case study considers the occurrence of conflict events, such as riots, protests, and terrorist activity insouthern regions of Asia.

CAPEL, Tara Michelle

Thesis Title

Making a Makerspace: Reimagining Makerspaces for Women's Participation

Supervisors

• Professor Margot Brereton  (Principal Supervisor)
• Dr Bernd Ploderer  (Associate Supervisor)

Citation

This thesis investigated how makerspaces can be designed in more inclusive ways to promote participation by women. It identified three core qualities – appropriate labelling,the configuration of learning, and turning ambitions into an artefact - that foster women’s participation and growth into confident and competent makers. This thesis alsodemonstrates how the configuration of new spaces, which facilitate engagement with new tools and materials, can lead to new areas of design, allowing new opportunities forself-expression, dialogue and reflection between participants, participants and researchers, and participants and the items they create.

CASH, Christina May

Thesis Title

Investigating the Genetics of Equine Endocrine Dysfunction

Supervisors

• Professor Peter James Prentis  (Associate Supervisor)
• Associate Professor Melody Anne de Laat  (Principal Supervisor)

Citation

Equine Metabolic Syndrome (EMS) and Pituitary Pars Intermedia Dysfunction (PPID) are metabolic disorders that increase a horse’s risk of developing endocrinopathic laminitis a debilitating disease of the equid hoof, in which the pedal bone is displaced from the hoof wall. These disorders are believed to possess an underlying genetic component that is yet to be identified. This thesis examined four target genes with biological relevance to EMS and PPID and discovered three genetic variants associated with characteristics of EMS and/or PPID. It is hoped the finding of this study will influence future research into the underlying genetics of these disorders.

COLE, Cameron MacKillop

Thesis Title

Ink-Jet Printable Thermally Activated Delayed Fluorescent Polymers for Organic Light Emitting Diodes

Supervisors

• Distinguished Professor Christopher Winfried Barner-Kowollik  (Associate Supervisor)
• Associate Professor James Peter Blinco  (Associate Supervisor)
• Professor Prashant Murlidhar Sonar  (Associate Supervisor)
• Associate Professor Soniya Devi Yambem  (Principal Supervisor)

Citation

This thesis bridges the gap between ink-jet printing and thermally activated delayed florescent (TADF) materials, by developing ink-jet printed TADF polymer organic lightemitting diodes (OLEDs). TADF materials have become one of the leading emissive materials for highly efficient OLEDs, however, majority of TADF OLEDs are fabricatedusing expensive and size-limiting techniques. Ink-jet printing can reduce the fabrication costs of OLEDs, with the added benefit of being scalable and patternable. In this thesis,TADF polymers are ink-jet printed for simplified OLEDs and also demonstrated in flexible OLEDs. These developments are foundational and pave pathways for fully printableOLEDs.

DAVIS, Joshua Taylor

Thesis Title

Separation of Thermal and Nonlinear Optical Effects in Normalized Transmittance Results of Colloidal Nanoparticles in Z-Scan

Supervisors

• Professor Aijun Du  (Associate Supervisor)
• Professor Esa Antero Jaatinen  (Principal Supervisor)

Citation

This project is a step to understanding the optical response of nanoscale gold particles suspended in water to exposure by intense laser irradiation. It theoretically models theresponse of electrons, the heating and phase changes of the gold nanoparticles and surrounding medium to allow for the accurate prediction of light-nanoparticle interactions.The thesis investigates the nonlinear optical response through the z-scan experiment and successfully predicts experimental data over a wide range of nanoparticle sizes andlaser intensities.

DAVOUDABADI, Mohammad Javad

Thesis Title

Bayesian Model Selection and Inference for Field Studies of Soil Carbon Cycling

Supervisors

• Professor Christopher Colin Drovandi  (Associate Supervisor)
• Dr Daniel Edward Pagendam  (External Supervisor)
• Dr Gentry Adair White  (Principal Supervisor)

Citation

Farmers and land managers can yield financial gains through the sale of carbon credits. They typically rely on computationally complex models fit using sparse datasets tomake predictions concerning soil carbon stocks and associated carbon accounts which can lead to over-fitting. We develop new soil carbon models to address the over-fittingissue and evaluate the effect of microbial biomass on modelling soil carbon sequestration. Also, we introduce and evaluate advanced Bayesian methods to improve the speedof computation and accuracy of predictions of soil carbon stocks.

DE JESUS, Alma Lorelei

Thesis Title

Urban Ambient Particles: Long-term Spatio-temporal Trends and  Impacts of Different Control Measures

Supervisors

• Dr Luke David Knibbs  (External Supervisor)
• Dr Mandana Mazaheri  (External Supervisor)
• Distinguished Professor Lidia Morawska  (Principal Supervisor)
• Associate Professor Mery Helena Thompson  (Associate Supervisor)

Citation

This thesis is a quantitative analysis of the spatial and temporal variability as well as trends of the particulate matter concentrations in the ambient urban air. The outcomeprovided a clear understanding on how the different metrics (particle number, particle mass and oxidative potential) were affected by mitigation measures and other importantdrivers such as emission sources and meteorological factors.

DEMA, Tshering

Thesis Title

Engaging Remote Communities In Technology Design for Connecting People to and Through Nature

Supervisors

• Professor Margot Brereton  (Principal Supervisor)
• Professor Paul Roe  (Associate Supervisor)
• Dr Michael Ward Towsey  (Associate Supervisor)
• Dr Jinglan Zhang  (Associate Supervisor)

Citation

Dominant citizen science paradigms to support species conservation typically rely on large, distributed populations to gather or analyse data. Engagement approaches areprimarily utilitarian and individualistic. This dissertation rethinks the way we engage citizens and communities to combat the problem of species loss. Long-term socio-technicaldesign research was carried out focusing on the critically endangered, White-bellied Heron in remote communities of Bhutan. The thesis contributes practical design outcomes,a co-design method that emphasizes “network of relations” and findings from a long-term technology trial.  It shifts design foci towards ‘stewardship beyond monitoring’ with aholistic view to enhancing nature engagement.

DENDLE, Nicholas Xavier

Thesis Title

Reactive Mine Optimisation with Grade Engineering

Supervisors

• Associate Professor Paul Gerard Corry  (Principal Supervisor)
• Associate Professor Thierry Peynot  (Associate Supervisor)

Citation

This project investigated mathematical optimisation methods to improve open-pit mine management, on a minute-to-minute scale. High-performance computer simulationswere designed to represent complex mine site processes and understand how changes in mining practices and truck movements could enhance efficiency. By incorporatingthe effect of dispatching strategies and random factors like breakdowns and small variations in mined rock, improved processes were developed to adapt to changing mineconditions in near real-time. Through combining diverse mathematical optimisation and machine learning techniques, improved ways to handle complex real-world problemswere identified, with important implications for future large-scale, complex decision-making in mining.

GAN, Hongxiao

Thesis Title

Animal Call Recognition with Acoustic Indices and Machine Learning

Supervisors

• Professor Yuefeng Li  (Associate Supervisor)
• Professor Paul Roe  (Associate Supervisor)
• Dr Jinglan Zhang  (Principal Supervisor)

Citation

This research aimed to recognise animal calls in audio recordings using machine learning algorithms with generic features of ecoacoustic indices. Several novel recognisers fordifferent animal calls were proposed, including anuran species, Wallum Sedgefrog, and its competitor Eastern Sedgefrogs and a cryptic vocal species, Kiwi. These proposedmethods utilised acoustic indices as features of audio data, implemented multiple machine learning algorithms modified for animal call recognition, and provided detailedanalysis of data selection issues in this area. The collective outputs of this research provided a useful solution for improving the efficiency of long-term acoustic monitoring.

GHAZJAHANIAN, Mohammadali

Thesis Title

Development of a Novel Biocatalytic Process to Produce Codeine from Thebaine

Supervisors

• Professor Sally Louise Gras  (External Supervisor)
• Adjunct Professor Robert Edward Speight  (Principal Supervisor)
• Dr Peter James Strong  (Associate Supervisor)

Citation

A new method for the production of pharmaceutical codeine from poppy-derived thebaine was developed. A biocatalytic route using microbial whole cells was investigated andoptimised to express key enzymes that could accumulate codeine as the dominant product. The cells were processed to generate stable biocatalysts that could be recycledand that regenerate essential cofactors. The experimental findings were used to develop techno-economic models to assess the commercial viability of manufacturing ofcodeine using this new method.

GROTH, Robert William

Thesis Title

Physicochemical Properties of Respiratory Aerosol

Supervisors

• Dr Graham Richard Johnson  (Associate Supervisor)
• Professor Zoran Ristovski  (Principal Supervisor)

Citation

Public, and scientific, interest in the transmission of respiratory viruses has become more prominent with the emergent SARS-CoV-2 pandemic. This thesis addresses gaps in knowledge surrounding the exact composition of respiratory particles to better understand the factors which influence the viability of airborne viruses.

HAKAMUWA LEKAMLAGE, Dulari Kaushalya Jayarathna

Thesis Title

Computational and Statistical Analyses of Omics Data to Advance Understanding of Hormone-Dependent Cancers

Supervisors

• Associate Professor Jyotsna Batra  (Associate Supervisor)
• Adjunct Professor Neha Gandhi  (Principal Supervisor)
• Dr Miguel Renteria  (External Supervisor)
• Professor Emilie Janette Sauret  (Associate Supervisor)

Citation

This thesis is focused on developing a computational framework to identify novel risk associations between various genetic factors and cancers and looks explicitly at regions that are not translated into proteins, an emerging area of computational genetics. The outcome of this study resulted in a novel set of biological and molecular-level risk factors which have the potential to develop/control cancer cells, thus providing rigorous and testable hypotheses for experimental studies.

HARTL, Hugo Mitchell

Thesis Title

Plasma-Enabled on-Surface Synthesis

Supervisors

• Associate Professor Jennifer May MacLeod  (Principal Supervisor)
• Professor Kostyantyn Ostrikov  (Associate Supervisor)

Citation

This thesis investigates a pathway to fabrication of surface coatings with a number of useful properties, like superhydrophobicity (extreme water repellence), antimicrobial, and high adhesive strength. Creation of coatings can currently require very precise and energy intensive processing, limiting scope and scale. This research involved the application of atmospheric pressure plasma at room temperature to enable chemical reactions of liquid organic precursors. By varying the plasma parameters (power and time), catalysts, substrates, and precursors, it was possible to control the properties of films created. The thesis demonstrates how this easy, quick method shows versatility in the fabrication of useful coatings.

HOLLAND, Oakes Camilla

Thesis Title

Assessing the Risk of Marine Invasive Species to Nearshore Marine Ecosystems of Australia's Antarctic Research Stations and Subantarctic Islands

Supervisors

• Associate Professor Kate Jessica Helmstedt  (Associate Supervisor)
• Dr Justine Desiree Shaw  (Associate Supervisor)
• Professor Kerrie Ann Wilson  (Principal Supervisor)

Citation

The oceans surrounding Antarctica represent one of the last pest-free regions of the world. However, climate change is breaking down the barriers to invasion, putting theseecosystems at risk. This work represents the first comprehensive risk assessment for the threat of marine invasive species to nearshore environments around Australia’sAntarctic research bases and subantarctic islands. The overall risk of marine invasive species is high, due to the potential for invasive species to plausibly cause native speciesextinctions in the study locations. Strengthening invasive species policy at national and international levels will help to reduce this threat to these locations.

HORMOZI, Elham

Thesis Title

Energy-Efficient Virtual Machine Placement in Data Centres via an Accelerated Genetic Algorithm

Supervisors

• Professor Yuchu Tian  (Principal Supervisor)
• Professor You-Gan Wang  (Associate Supervisor)

Citation

Energy-efficient data centre management is crucial for cloud computing. This research accelerates the Genetic Algorithm (GA) for VM placement, simplifying the fitnessfunction calculation. The accelerated GA outperforms the standard GA and First Fit Decreasing (FFD) algorithm, saving 7% energy and reducing execution time by 50%. It alsoenables more PMs to be switched off, improving energy efficiency. Task classification and profiling concepts optimize energy efficiency, considering future task arrivals. Thisresearch enhances performance and computational efficiency in cloud data centres.

JAMES-PEARSON, Louisa Fern

Thesis Title

Characterisation of the Australian Great Artesian Basin's Caldaquabacillus Species and Potential Role in Thermophillic Plastic Biodegradation

Supervisors

• Dr Kevin John Dudley  (Principal Supervisor)
• Dr Pawel Grzegorz Sadowski  (Associate Supervisor)
• Adjunct Associate Professor Valentino Setoa Junior Te'o  (Associate Supervisor)

Citation

Plastic waste accumulation is a significant problem facing the world, with current plastic recycling strategies proving unsustainable. In this study, the biological breakdown ofplastics at cellular and enzymatic levels was examined. Great Artesian Basin bacterial strains were characterised and classified as belonging to an entirely new genus. Cellswere found to partially degrade LDPE plastic under high-temperature conditions. Then, in a novel approach, this study developed a heat pretreatment procedure whichenhanced plastic biodegradation. Pretreated PBAT plastic was significantly degraded via enzymatic activity. Therefore, this research contributes towards fast, high-temperaturebiodegradation strategies, and helps work towards a waste-free world.

JENKINS, Tristram Henry Morgan

Thesis Title

Structure and Surface Properties of High-Energy Cathode Materials for Alkali Ion Batteries

Supervisors

• Professor Jose Antonio Alarco  (Principal Supervisor)
• Professor Ian Donald Richard Mackinnon  (Associate Supervisor)

Citation

Alkali-ion batteries, namely Li-ion batteries, are the world’s most ubiquitous energy storage technology, but limitations in electrode capacity and lifespan hinder furtherdeployment. To address this, improved design of cathode materials is required. This thesis examines the link between the surface electronic properties of high-energy cathodematerials and real-world battery performance. Using computational and experimental approaches, alkali vanadium (III) phosphates were investigated as cathode coatings,leading to enhanced electrochemical performance of high-energy cathode material, Li_1.2Mn_0.54Ni_0.13Co_0.13O₂. These outcomes establish that electronic alignment ofsurface coatings and active material can boost battery performance, offering an innovative design methodology for future battery development.

KAY, Bianca Jayde

Thesis Title

The Complexity of Competition Between Three Native Australian Fruit Fly Species, Bactrocera tryoni, B. neohumeralis and B. jarvisi in a Changing Environment

Supervisors

• Professor Anthony Robert Clarke  (Principal Supervisor)
• Professor Peter James Prentis  (Associate Supervisor)

Citation

This thesis studies competition between three endemic Australian fruit fly species, Bactrocera tryoni, B. neohumeralis and B. jarvisi, all which are considered to have peststatus in Australia. Intra- and interspecific interactions were investigated between adult females competing for oviposition substrates through video analysis and behaviouralobservations, as well as laboratory studies investigating larval competition, all within a changing environment. To further add to the outcomes of these investigations, theinfluence of a third trophic level on the outcome of competition was investigated and evaluated for future fruit fly control predictions.

KOGGALAHEWA, Darshika Niranjan

Thesis Title

Spammer Detection in Social Networks Based on User Behaviours

Supervisors

• Adjunct Associate Professor Ernest Foo  (Associate Supervisor)
• Adjunct Professor Shlomo Geva  (Associate Supervisor)
• Associate Professor Yue Xu  (Principal Supervisor)

Citation

This thesis unveils a novel methodology for identifying social spammers through an innovative analysis of user behaviours. The battle against social spammers has emerged as a formidable obstacle in online social networks (OSNs). Although classification-based approaches have garnered significant popularity in combating social spammers, they are plagued by persistent challenges related to data labelling and spam drift. To overcome these obstacles, this thesis introduces a pure unsupervised approach for detecting social spammers, along with a novel strategy for effectively managing spammer drift in OSNs.

KOOHI, Maedeh

Thesis Title

Development of Nanoformulations for the Enhanced Delivery of Target Drugs

Supervisors

• Associate Professor Peter John Cabot  (External Supervisor)
• Dr Mohd Nazrul Islam  (Associate Supervisor)
• Dr Emad Kiriakous  (Principal Supervisor)

Citation

This work provides nanoformulations of some potential anticancer drugs that could improve drug delivery into prostate cancer cells. For this purpose, two types of nanoparticles (mesoporous silica nanoparticles) were produced, and the potential anticancer drugs were encapsulated into the nanoparticles. After investigating and examining the prepared nanoformulations in the laboratory, the best potential anticancer formulation was found.

MAHAWAGA ARACHCHIGE, Nayomi Dulanjala Sewwandi

Thesis Title

In-depth Feature Selection for Continuous Data Classification with Granule Mining

Supervisors

• Professor Yuefeng Li  (Associate Supervisor)
• Dr Jinglan Zhang  (Principal Supervisor)
• Dr Xujuan Zhou  (External Supervisor)

Citation

This study proposes theories and algorithms to select features for in-depth groups of data identified as granules, using granule mining techniques to improve the classificationperformance of continuous data. Global, class-specific, and granule-specific feature selections are performed to observe the significance of granule-specific feature selectionwhen the datasets contain objects that cannot be correctly defined by the given features.  Since the granules can be treated as the subclasses of a dataset, the outcomes ofthis study can be used for selecting features and mining in-depth knowledge in data analysis applications where the data does not contain the subclass information.

MOHOMED HASEEM MOHOMED AMSAR, Mohomed Abraj

Thesis Title

Multivariate Anisotropic Spatial Modelling and Sampling Design Using Copulas

Supervisors

• Associate Professor Mery Helena Thompson  (Principal Supervisor)
• Professor You-Gan Wang  (Associate Supervisor)

Citation

This thesis presents novel copula-based spatial models to improve the accuracy of predictions for spatial variables with multivariate and anisotropic relationships. These models are utilised to develop more effective sampling design frameworks, which can benefit industries modelling and analysing data measured over space. The methods presented in this research have broad applicability, such as to the fields of geology, meteorology, geochemistry, and forestry, and can lead to more informed management decisions while reducing field sampling costs.

MOHOTTI, Wathsala Anupama

Thesis Title

Unsupervised Text Mining: Effective Similarity Calculation with Ranking and Matrix Factorization

Supervisors

• Adjunct Professor Shlomo Geva  (Associate Supervisor)
• Professor Richi Nayak  (Principal Supervisor)

Citation

The popularity of the internet has increased the availability of digital text on social media, online forums, news broadcasting services, web blogs, and websites. Text mining isan effective approach to extract concepts, clusters, user communities, outliers and dynamic changes in the text collections. This thesis developed unsupervised machinelearning techniques to identify these patterns by dealing with high dimensional and sparse text data. More specifically, this thesis developed effective measures of pairwisesimilarity and extended them in implementing clustering, outlier detection and cluster evolution methods to produce accurate and efficient outputs.

NEWMAN, Jaye Deborah

Thesis Title

Determining the Influence of Organism Level Processes on the Population Dynamics of Bactrocera tryoni

Supervisors

• Professor Anthony Robert Clarke  (Principal Supervisor)
• Associate Professor David Alan Hurwood  (Associate Supervisor)
• Dr Hazel Parry  (External Supervisor)

Citation

The Queensland fruit fly is a major horticultural pest in Australia, infesting over 100 fruit species. This thesis examines the impact of host fruit quality on the population dynamics of this pest. The quality of the host fruit affects the growth and development of larvae, which in turn influences adult traits such as size, fecundity, longevity, and flight, potentially impacting population dynamics. An individual-based model was used to simulate population dynamics in various host quality landscapes, revealing that the availability and quality of fruit significantly influences the population dynamics. The model has potential applications in on-farm management of fruit flies.

PINHEIRO DE OLIVEIRA MARTINEZ, Juan

Thesis Title

Understanding Enzyme-Mediated Keratin Hydrolysis and Evaluation of New Keratin Binding Peptides

Supervisors

• Professor Kirill Alexandrov  (Associate Supervisor)
• Dr Wayne Johnston  (Associate Supervisor)
• Dr Laura Navone  (Associate Supervisor)
• Adjunct Professor Robert Edward Speight  (Principal Supervisor)

Citation

Keratin is the main structural protein in hair, wool, nails, horns, and hooves. This study explored the potential of waste keratin as a resource for new products. Enzymatic hydrolysis was used to process keratin, and keratin powder was used as a support for biocatalysts fused with keratin-binding peptides. Various protease enzymes were effective for controlled keratin breakdown, and new keratin-binding peptides were identified and characterized. Industrial enzymes were fused with these peptides to bind to keratin powder, creating sustainable biocatalytic systems. These innovations open new possibilities for using keratin as a valuable resource.

ROOMKHAM, Sirinthip

Thesis Title

The Potential of Personal Devices in Large-Scale Sleep Studies

Supervisors

• Professor David Roger Lovell  (Associate Supervisor)
• Associate Professor Dimitri Perrin  (Principal Supervisor)

Citation

This thesis investigated the use of consumer wearable devices to gather large quantities of data in naturalistic settings and enable large-scale sleep studies. By exploiting themassive uptake of mobile phones and wearable devices and using the data they produce for large-scale sleep monitoring, this research opens the way for a betterunderstanding of sleep dynamics which, in turn, are known to play a crucial role in health.

SCARPELLI DRUMMOND DE ALMEIDA, Marina

Thesis Title

Multidimensional Terrestrial Ecoacoustics Assessment

Supervisors

• Associate Professor Susan Jayne Fuller  (Associate Supervisor)
• Professor Paul Roe  (Principal Supervisor)
• Dr David Ian Tucker  (External Supervisor)

Citation

Ecologists faces challenges when analysing environmental acoustic data, such as handling big data, summarising and comparing long-duration recordings across regions andtimescales. This thesis provides an innovative framework that combines time-series motif discovery and machine learning for analysing environmental sounds. The proposedmethodology was successfully applied to different temporal and spatial scales, demonstrating its applicability across different contexts. The new framework provides a fasterand better tool to assess environmental sounds, improving the understanding of biodiversity, uncovering patterns and better distributing resources directed at biodiversityconservation.

SINGH, Manika

Thesis Title

Improving SWATH-MS Data Analysis Using Multi-Omics Approach

Supervisors

• Professor Michelle Colgrave  (External Supervisor)
• Dr Kevin John Dudley  (Associate Supervisor)
• Dr Annette McGrath  (External Supervisor)
• Associate Professor Anthony James Parker  (Mentoring Supervisor)
• Dr Pawel Grzegorz Sadowski  (Principal Supervisor)

Citation

Proteomics research has relied on publicly accessible sequence databases for mining peptide fragmentation patterns and deriving biological information. The limitation of thisapproach is that databases are as good as genome annotation, which can be incomplete or not available for non-model organisms. A novel reference genome-independentproteomics pipeline termed DIA-Seq is introduced. The pipeline integrates the advancements of long-read RNA sequencing (Iso-Seq) and deep learning neural network toolsfor isoform-specific peptide spectra prediction and SWATH-MS based quantification. DIA-Seq pipeline developed in the study improves annotation of a well-characterizedmodel organism. It has the potential to fast-track discoveries in non-model species.

THOMPSON, Kristen Louise

Thesis Title

Using Acoustic Monitoring to Evaluate Faunal Biodiversity in Urban Restoration

Supervisors

• Associate Professor Susan Jayne Fuller  (Principal Supervisor)
• Adjunct Professor Bradley Law  (External Supervisor)
• Adjunct Professor Stuart Parsons  (Associate Supervisor)

Citation

Few studies have documented faunal restoration in urban bushland. This study used acoustic monitoring to compare fauna in remnant and restored urban bushland and investigated the vegetation and landscape attributes that may predict faunal biodiversity. Results showed that acoustic indices and bat assemblages did not vary between remnant and restored bushland sites. Site-level variation was a consistent finding in this study indicating that urban restoration often transitions to a novel state. This study has concluded that a combination of acoustic and vegetation monitoring should be undertaken at regular intervals, over long periods, to track faunal restoration in urban bushland.

UDA GEDARALAGE, Mihiri Ekanayake

Thesis Title

Plasma Assisted Nanomaterials Synthesis from Sustainable Sources

Supervisors

• Associate Professor Jennifer May MacLeod  (Associate Supervisor)
• Professor Anthony Peter O'Mullane  (Associate Supervisor)
• Professor Kostyantyn Ostrikov  (Principal Supervisor)

Citation

Travel’s power to transform individuals originates from both destinations and experiences, and yet, destinations remain unexamined within transformative tourism research. Using destination image as its theoretical scope, this thesis proposes the idea of ‘transformative destinations’ highlighting the importance of personal values and affect-based strategies to encourage positive behavioural intentions within this context. For this, a mixed methods approach was taken in which the first study used the Repertory Test with Laddering Analysis while the second study was a survey.

WANG, Sen

Thesis Title

Effects of Kaolinite, Vermiculite and Palygorskite on Fired Clay Brick Properties

Supervisors

• Lloyd Gainey  (External Supervisor)
• Professor Ian Donald Richard Mackinnon  (Associate Supervisor)
• Associate Professor Yunfei Xi  (Principal Supervisor)

Citation

This thesis reveals the role of different clay minerals in the fired brick production process. Multiple in-situ characterisation techniques have been effectively combined to studythe thermal behaviour of clayey materials added with kaolinite, expandable vermiculite, and nanofibrous palygorskite at various dosages. Laboratory-scale brick buttons areobtained to test the mineralogical composition, mechanical strength, density, porosity, colour, water absorption, and thermal diffusivity. The conclusions obtained can effectivelyassist brick manufacturers and researchers in achieving optimised clay mix design to obtain maximum economic efficiency and quality.

WANG, Xuelei

Thesis Title

Detecting Cyber Attacks from Untrusted Components in Smart Electricity Substations

Supervisors

• Professor Colin John Fidge  (Principal Supervisor)
• Adjunct Associate Professor Ernest Foo  (External Supervisor)
• Dr Zahra Jadidi  (Associate Supervisor)
• Dr Ghavameddin Nourbakhsh  (Associate Supervisor)

Citation

Modern power grids have been experiencing a digitisation process in recent decades. Particularly, substation automation systems which monitor and protect the physicalprocesses of electricity substations, have been developing with more intelligence. However, the advancement of "smart" substation automation systems not only bringsconvenience to the control process but also introduces new security issues. Motivated by a common concern from the energy industry about the dangers posed by untrustedthird-party components, our research focuses on protecting a substation from untrusted devices which have been installed inside its security perimeter.

WEERASINGHE, Weerasinghe Mohottige Hasitha Nilakshi

Thesis Title

Mathematical Modelling for the Tumour Microenvironment (TME) under Cellular Stress

Supervisors

• Dr Pamela Marion Burrage  (Principal Supervisor)
• Associate Professor Dan Valeriu Nicolau  (Associate Supervisor)

Citation

This thesis discovers mathematical modelling techniques that can be applied to the stressful tumour microenvironment (TME) by developing an agent-based model, systems ofordinary differential equations (ODEs) and systems of stochastic differential equations (SDEs) driven by Chemical Langevin Equations (CLEs). The study suggests thatunderstanding intra-tumoural communication in the TME at the cellular and tissue level supports identifying significant tumour microenvironmental factors that may causetumour cell malignancy.

WEERATHUNGA, Kaluarachchige Don Helapiyumi Uthpala

Thesis Title

Metal Nanoparticle and Semiconductor Heterogeneous Catalysis for Synthetic Organic Oxidation Reactions

Supervisors

• Associate Professor Eric Rolfe Waclawik  (Principal Supervisor)
• Professor Huai Yong Zhu  (Associate Supervisor)

Citation

This thesis investigated new metal nanoparticle and semiconductor catalyst and photocatalyst systems for achieving fine chemical synthesis from both fossil-fuel sourcedreactants and biomass carbohydrate-derived reactants. Photocatalysts for industrially important organic oxidation reactions were developed that efficiently worked with the aidof solar light irradiation, at low temperature and pressure, that avoided the use of hazardous chemicals. The effects on the organic reaction mechanisms of different noblemetal nanoparticle and metal oxide nanostructures were explored for these chemical transformations. Success in developing the nanomaterial photocatalysts has contributedto the field of sustainable green chemical synthesis.

ZEBARDASTAN, Negar

Thesis Title

Van der Waals Epitaxy of Transition Metal Dichalcogenides on Graphene

Supervisors

• Associate Professor Jennifer May MacLeod  (Associate Supervisor)
• Professor Nunzio Motta  (Principal Supervisor)
• Professor Kostyantyn Ostrikov  (Associate Supervisor)

Citation

This research is a fundamental study of the direct epitaxial growth of MoS₂ on diverse types of graphene substrates, including self-standing and graphene/SiC, using chemicalvapour deposition (CVD). The size, quality, and growth rate of epitaxial graphene on SiC, subsequently used as a substrate for the formation of MoS₂, is controlled with highprecision using a novel face-to-face technique in ultra-high vacuum. The effect of growth parameters and substrate characteristics on the CVD growth of MoS₂ are investigatedto design an optimised viable approach for the growth of high-quality MoS₂/Graphene heterostructures.

ZHANG, Mengchen

Thesis Title

Fractional Dynamic Models and Numerical Simulations of the Anomalous Diffusion in the Human Brain

Supervisors

• Emeritus Professor Vo Van Anh  (External Supervisor)
• Professor Fawang Liu  (Principal Supervisor)
• Professor Ian William Turner  (Associate Supervisor)

Citation

Diffusion-weighted magnetic resonance imaging is an advanced imaging technique that provides detailed information for clinical diagnosis and treatment monitoring. Thepurpose of this thesis is to establish fractional dynamic models for better characterising anomalous diffusion in biological tissues of the human brain and explore reliablenumerical methods. The introduced generalised fractional operators and variable diffusion coefficients provide more possibilities for capturing structural heterogeneity anddiffusion complexities in biological tissues. Robust and efficient numerical methods are developed to solve the proposed fractional systems with lower computational costs.

Outstanding Doctoral Thesis Awards

BAYOR, Andrew Azaabanye

Thesis Title

Leveraging Social Media to Co-Design Support for Developing Life Skills Among Young Adults with Intellectual Disability

Supervisors

• Professor Margot Brereton  (Principal Supervisor)
• Dr Bernd Ploderer  (Associate Supervisor)
• Professor Paul Roe  (Associate Supervisor)
• Associate Professor Laurianne Julie Sitbon  (Associate Supervisor)

Citation

Many people with intellectual disabilities are keen users of the internet and social media. This research explored how their existing competencies with these technologies couldbe leveraged in order to design better social technologies to support their societal inclusion and skills development. The thesis contributes: (1) the Competency-Based designframework, an approach that is grounded in revealing the existing contextual competencies of users, rather than more generic measures of ability, and leveraging them intechnology design; (2) the research method of “TechShops”, technology workshops that foster reciprocity–learning for both researcher and participants; and (3) a prototype skilllearning interface.

ROOHIGOHAR, Shirin

Thesis Title

Characterisation of the Interactions Between Queensland Fruit Fly, Bactrocera Tryoni, Egg and Larvae, and Tomato Fruit at the Whole Insect and Molecular Level

Supervisors

• Professor Anthony Robert Clarke  (Principal Supervisor)
• Professor Peter James Prentis  (Associate Supervisor)

Citation

Fruit flies are major pests to a wide range of fruits and vegetables as their larvae cause damage and yield loss. To replace pesticide-based controls with more sustainablemanagement approaches, we need to develop new generation technologies. This thesis focuses on molecular and whole-organism studies to investigate the interactionsbetween Queensland fruit fly larvae and tomato fruit. Through molecular analysis, different mechanisms were identified to determine the susceptibility of various tomatovarieties to fruit fly damage. The results pave the way for future studies on breeding for fruit resistance to fruit fly attack and sustainable pest management.