Cytoskeletal plakins in epithelial ovarian cancer
- Authors: Wesley, Tamsin
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: The plakin family of cytoskeletal proteins play an important role in cancer progression yet are under-studied in cancer, especially ovarian cancer. These large cytoskeletal proteins have primary roles in the maintenance of cytoskeletal integrity. They are also associated with scaffolds of intermediate filaments and hemidesmosomal adhesion complexes mediating signalling pathways that regulate cellular growth, migration, invasion and differentiation, as well as a stress response. Abnormalities of plakins, and the closely related spectraplakins, result in serious pathologies of skin, striated muscle and nervous tissue. Their prevalence in epithelial cells suggests that plakins may play a role in epithelial ovarian cancer progression and recurrence. This thesis sought to explore the expression of plakin proteins, particularly plectin (PLEC), desmoplakin (DSP), periplakin (PPL) and envoplakin (EVPL) in ovarian cancer progression, comparing surgical stages, historical Silverberg histological grading and current World Health Organisation (WHO) pathological classification of ovarian tumour types. The study also investigated the potential role that the plakin family of proteins may play in regulating cancer cell growth, survival, migration, invasion and drug resistance. It highlights potential relationships between plakins and epithelial-mesenchymal transition (EMT) and relates how these interactions may affect ovarian cancer progression, chemoresistance and ultimately recurrence. This study hypothesises that the molecular changes in the expression of plakins in benign ovarian tumours compared to various grades and stages of ovarian carcinomas, as well as floating cellular aggregates (spheroids) in the peritoneal ascites microenvironment, may contribute to the progression of the disease. It also attempts to understand these crucial changes in plakin expression in response to chemotherapy treatment and relate these findings in the perspective of disease recurrence.
- Description: Doctor of Philosophy
Development of scaled boundary finite element method for geotechnical and mining engineering
- Authors: Wijesinghe, Dakshith
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Numerical methods are a mature field of research and have become an increasingly important tool in mining and geotechnical engineering design practices. Although the advantages of numerical methods in aiding the analysis and solving practical engineering problems have been widely accepted and recognised, there is still a gap for further improvements. One such area is the challenge to consider the complexities of geology and the lack of stratigraphic information in the numerical model. Failure to include geological complexities may lead to overestimating the analysis parameters, such as the safety factor. These difficulties mainly manifest in the form of complex mesh generation due to the need to integrate spatial variable material parameters, capturing complex geological features, requirement of additional meshing algorithms, high human involvement, and long processing time. The scaled boundary finite element method (SBFEM) is a semi-analytical method that has potential to address these types of problems. This thesis focuses on developing the SBFEM to address these challenges so that complex geotechnical and mining engineering can be better modelled. Optimisation problems in geotechnical and mining engineering are also considered by developing a combined SBFEM-genetic algorithm framework for the design and rehabilitation of slopes. To begin with, an image-based mesh generation procedure is developed to automatically integrate the spatially variable material parameters into a computational mesh. The procedure allows the input of large data sets of geological and geometrical information in image format, and the mapping procedure enables the concatenation of any number of material parameters into a single computational mesh. The scaled boundary finite element formulation is used to discretise the governing equations of elasto-plasticity considering a Mohr-Coulomb failure criterion, which is common in soils. A shear strength reduction technique is implemented to analyse the stability of slopes in the form of an output Factor of Safety. The developed method is shown to allow routine changes in the operation of the slopes to consider geometric changes, such as backfilling, excavation and updates to geological sublets, by simply editing the digital image inputs. To extend the SBFEM to more complex geotechnical and mining engineering applications, a formulation that considers the coupled effect of pore pressure and nonlinear deformation of the soil is developed. The image-based mesh generation procedure is incorporated to integrate the geological complexities, which include heterogeneity of strate and phreatic surfaces. The developed technique is applied to study complex case studies of a tailings dam embankment construction and a coal slope rehabilitation project with a construction period. The research also considers geometric optimisation problems within the context of geotechnical and mining engineering applications. Geometric optimisation of slopes such as those in open cut mines is important to reduce the overhead operational cost involved in construction, excavation and rehabilitation backfilling, while ensuring stability at an acceptable level. This is achieved by developing a unified platform combining genetic algorithm (GA) with scaled boundary finite element formulations and image-based meshing procedures. Since the image-based mesh generation procedure is an automatic process, it enables automation of the optimisation, which is an iterative proceeding. The capabilities of this technique are demonstrated by optimising the geometric parameters of complex slopes for given safety factors and rehabilitation geometries for given safety factors during a given construction period. The image-based SBFEM analysis platform is further developed to consider geological uncertainty, such as stratigraphic interfaces and phreatic surface fluctuations, so that their effect on slope stability can be studied. The Brownian bridge statistic technique is integrated into the pre-processing module to produce these instances reflecting the ranii dom fluctuations between two intervals and generate possible geological and hydrological cross-sections. This allows unknown geological stratigraphic interface fluctuation due to a lack of sublet information to be considered. The scaled boundary finite element formulations developed in the earlier parts of this thesis are used to discretise each generated profile and analysis probabilistically. Since the mesh generation method is fully automatic, this probabilistic analysis procedure enables to analyse of a large number of possible variations and their effect on geotechnical structures with limited human intervention. Few parametric studies were conducted on slopes to study the impact of stratigraphic and phreatic surface fluctuation on the probability of failure. Finally, the hydraulic fracture commonly seen in geotechnical and mining engineering applications is considered. The phase field has the potential to model complex fracture mechanisms including crack nucleation, branching and coalescence. However, it requires a very fine mesh in order to accurately regularise the energy resulting from the creation of new crack faces. This leads to longer processing time and high computational requirements. Moreover, fracture propagation modelling with phase field models requires equilibrium iterations and hence repetitive calculation of element matrices. This research develops a scaled boundary finite element formulation with phase field model to address hydraulic fracture problems in fully-saturated poro-elastic media. Adaptive meshing refinement based on quadtree meshes is applied. This restricts the fine mesh requirement to only the regions where damage is present and avoids the need for a very fine mesh throughout the structure. Further, leveraging from the unique number of patterns in a hierarchical mesh, an appropriate scaling technique is applied to transform the relevant matrices and vectors to the physical cell in the mesh. This avoids the need for repetitive calculations during the equilibrium iterations. These features increase the efficiency of fracture modelling while reducing the computational requirement. The benchmark problems and complex fracture network problems are provided to highlight the advantage of the method.
- Description: Doctor of Philosophy
Distribution of heavy metals in the sediments of the Gippsland Lakes, Victoria, Australia : implications for management
- Authors: Trewarn, Adam
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Sediments are the ultimate repository of most contaminants that enter Australia's waterways; therefore, it is appropriate that regulatory attention addresses the risks posed by sediment contaminants. The release of elevated levels of heavy metals into the environment is a common by-product of our industrialised way of life. This problem continues to increase throughout the industrial age. We are now only beginning to understand the actual long-term burden that must be managed. Globally, estuaries are a critical focal point for civilisation and development. Owing to their strategic location and abundant resources, they have been utilised as trade hubs and industrial centres, and are often subject to intense industrial and urban development. Because estuaries accommodate large volumes of fine-grained sediments, their capacity to trap and absorb metal pollutants qualifies them as important sinks and receptacles for terrestrial, atmospheric, and oceanic metal input. Estuaries also provide important environmental services. Their protective conditions harbour a diverse range of biota, and the biogeochemical processes they accommodate play a key role in nutrient cycling and metal sequestration. However, contamination of estuaries with heavy metals is an ongoing issue, particularly as they bioaccumulate and transfer from sediments to aquatic organisms through the food chain. The Gippsland Lakes catchment has a 150-year history of a range of industrial activities, including gold and other metal mining, large open-cut brown coal mines and associated coalfired power stations, powering much of the state of Victoria, plantation forests and associated timber and paper mills, and extensive agriculture, including intensive dairy. Many of these activities are potential sources of contamination, particularly in bygone times, when environmental awareness and sound practices were less prevalent. The issue of highly elevated levels of heavy metal contaminants present within the Gippsland Lake sediments was first identified over 35 years ago. This comprehensive study looks to re-evaluate the modern surface sediments from across the Gippsland Lakes to determine, (i) If previously identified elevated Hg levels are still present or can be replicated (ii) If there are other metal contaminants that may warrant further attention, (iii) If possible, contamination is current, historical or a prolonged event (iv) If there are any natural or anthropogenic influences affecting metal concentrations within the sediments (v) What is the impact of heavy metal pollution across the Gippsland Lakes? Surficial grab and consolidated core sediment samples were collected over a period between 2015-2018 from thirteen defined locations across the Gippsland Lakes, representing the major geomorphological features of the area (e.g. major river mouths and lakes). Total metal analysis, sediment grain size, and XRF high-resolution core scanning provided insight into the overall distribution and possible risks of bulk and heavy metals present in the Gippsland Lakes sediment. Elevated concentrations of Cr, Ni, As, Cu, and Hg were found throughout the study area, exceeding the lower SQG trigger values across multiple depths and locations. Of the numerous metals initially investigated (Cr, Ni, Cu, As, Cd, Hg, and Pb) within the surface and core sediments, the findings of this study reiterated that the greatest concern was the degree of contamination and distribution of elevated levels of Hg in the western regions of the Gippsland Lakes. In addition, it highlighted the risks associated with elevated levels of Cr, Ni, and Cu. Cr and Ni have been identified at elevated levels throughout most of the western locations, Lake Victoria and Lake King, while isolated Cu is present at Paynesville. Further analysis into the metals and the interactions with the environment has defined three separate influences contributing to the elevated concentrations of heavy metals present across the study area, (i) Natural sources and cycling (Cr, Ni, and As): Concentrations of Cr, Ni, and As are likely a result of natural sources from the surrounding catchment, rather than a specific anthropogenically derived source. (i) Diffuse anthropogenic sources (Hg): The calculated pollution indices showed little to no natural influence on Hg concentrations; therefore, Hg concentrations were deemed highly likely a result of diffuse anthropogenic origin. (ii) Point source (Cu): Concentrations of Cu were generally very low throughout the study, except at a single location in an urbanised area adjacent to a commercial boatyard. This project has provided the most recent and comprehensive assessment of the presence, distribution, and leading influences on heavy metals present in the Gippsland Lakes, forming a strong foundation for informed management of the area into the future.
- Description: Doctor of Philosophy
Effects of tailored peroxide oxidation on yield and molecular structure of humic substances from Victorian lignite
- Authors: Hood, Andrew
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Soil organic carbon is vital to soil health and productivity. However, its abundance declines as continually greater demands are placed on agricultural food and fibre production. Humic substances are key components within the soil carbon and confer many benefits to soil and plants. Therefore, demand is growing for external amendments to maintain productive soils, including humic substances (HS), specifically humates. There are many sources of these HS, including lignite and Leonardite. Leonardite represents a naturally oxidised lignite that exhibits a rich source of HS. The limitation is the low abundance of Leonardite or difficulties obtaining a reliable source. Lignites are abundant in Victoria (Australia) but lignite derived-humates are often subject to significant compositional and yield variability. Past research has primarily focused on oxidising lignite under low solids loading conditions to improve HS yield and water solubility. This research focuses on oxidising dense run-of-mine (RoM) lignite slurries (20% dry solids loading) that are more suitable for commercial production. The product chemical and molecular structures are compared with a reference Leonardite. Hydrogen peroxide served as the oxidising agent given its availability at a commercial scale and convenience. The controlled set of oxidation experiments showed that the ratio of oxidant to lignite and lignite composition had more impact on HS yields and chemical structure than slurry temperature and pH. Initial oxidation trials utilised an archived sample of carefully blended 2015 RoM (run of mine) lignite from the Loy Yang (LY) mine in Victoria, Australia. Additional fresh LY RoM lignite was obtained in 2021 to enable further larger-scale (10 and 100 L) reaction trials and assess the impact of sample variation and aging on oxidation reactivity. A substantial increase in humic acid yield (29% to 68%) was produced by mild oxidation using a 1:1 (w/w) ratio of the 2015 RoM lignite (db, dry basis) and 35% (w/v) hydrogen peroxide. For the lower quality 2021 RoM lignite, the humic acid content was elevated from 13% to 78% through oxidation with a 2:1 ratio of hydrogen peroxide to lignite (db). Mass and carbon balances, which are often given little consideration, show >64% (2015 RoM) and >84% (2021 RoM) carbon recovery, with the majority of losses attributed to volatiles including CO2 and small organic acids or aldehydes The optimum reaction conditions for humic and fulvic acid production from LY RoM lignite depend on the target products, RoM properties and other commercial considerations. Optimum conditions are likely to be in the region of: - 40°C to 60°C to balance reaction speed and peroxide efficacy. - High humic acid yields require between 1:1 to 1.5:1 peroxide (35% w/v) to lignite (db) ratio. - Minimising humin yields requires a minimum of 2:1 peroxide to lignite. - High fulvic acid yields require between 3:1 to 4:1 peroxide (35% w/v) to lignite (db) ratio. This research shows that Loy Yang RoM lignite can be progressively oxidised with hydrogen peroxide to produce commercially relevant yields of humic and fulvic acids. A large portion of the humin is converted into humic or fulvic acids, and what remained was more oxidation resistant and water-insoluble aliphatic components. Elemental proportions shift within each fraction during oxidation. For the 2015 and 2021 RoM lignite samples; the O/C for the reaction solids increased by 36% and 16% for the respective lignites. The O/C changes for the HAs were 22% and 19% respectively. The humin undergoes a sizeable shift in H/C ratio consistent with aliphatic enhancement. The ratios elevate by 14% with oxidation for both the 2015 and 2021 lignites. Extensive lignite, reaction slurry and reaction product characterisation including slurry pH, spectroscopy (UV-vis, FTIR and NMR), and pyrolysis GC/MS assist in understanding the structural changes occurring during oxidation as well as identify promising on-line reaction monitoring technologies. Elemental (CHNSO), FTIR, NMR and functional group titrations show that the fundamental organic structural changes to the humic acid fraction achieved through controlled oxidation were greater acidity (particularly carboxylic acid content) and a transition from aromatic to more aliphatic character overall. No combination of ratios or slurry conditions tested produced a humic acid with the same chemical structural properties as those extracted from the reference Leonardite. However, it is possible to match some properties under the combinations tested. Larger-scale reactions (10 and 100 L) show that real-time reaction monitoring as well as adequate heating and cooling capacity are essential for commercialising the conceptual lignite oxidation process. Proactively dealing with an inherently variable feedstock and humic product composition is heavily dependent on the intersection of multiple variables. For example, tracking pH, reaction enthalpy, and UV-vis absorbance of prepared samples can provide valuable real-time feedback on the progress of a reaction. Combining these techniques with redox titrations could measure residual peroxide and help manage reaction control parameters or better understand reaction kinetics for process optimisation.
- Description: Doctor of Philosophy
Language and the built, natural, social, and symbolic environments during bad news conversations for people with a life-limiting illness : a case study methodology
- Authors: Miller, Elizabeth
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Background Bad news of a life-limiting illness is devastating to receive and remains a difficult conversation for healthcare professionals to undertake, despite education and training. Bad news conversations occur anywhere along an illness trajectory and often take place with the acute ward that is busy, sterile, and unfamiliar to patients and family members. Method A qualitative case study research methodology was used to explore the case, being the phenomenon of receiving bad news of a life-limiting illness for people living in regional Victoria, Australia. The literature was examined to understand the physical hospital environment and truth disclosure within bad news delivery. Data was collected between November 2021 and August 2022, through 14 semi-structured interviews with patients and family members, 13 semi-structured interviews with registered nurses, a three week observation period at a private regional hospital. The theoretical framework of Therapeutic Landscapes enabled the built, nature, social, and symbolic environments to be examined. Data was analysed using reflexive thematic analysis and qualitative content analysis. Results A review of the literature resulted in the development of the "SSAFER place approach" concept model and found that patients need to feel safe in the hospital environment and that safety is equated with space for family and familiar notions of home. Nurses aimed to provide holistic person-centred through therapeutic relationships with patients and family members and create a home-life environment. It was found that a calm and quiet environment was essential for absorbing bad news, and patients and family members believed the way bad news was delivered, and the language used often needed to be improved. The audit of 17 family meeting s highlighted that death and dying language was rarely documented, and late referrals to palliative care services often occurred. The "Breaking bad news model," created from a second literature review supported the results of the thesis. Due to the COVID-19 pandemic, patients, family members and nurses were negatively affected, creating a non-therapeutic social environment. Conclusion For patients and family members, a therapeutic landscape comprised of therapeutic relationship, open, honest and empathetic language delivered within holistic person-centred care. In addition, care needed to be provided within a calm and quiet environment to allow absorption and processing of bad news. Nurses providing palliative care aimed to meet patients and family needs holistically within an environment aesthetically tuned to be more home-like than clinical.
- Description: Doctor of Philosophy
Organisational engagement of individuals with younger-onset dementia : maximising beneficial workplace outcomes
- Authors: Carino, James
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: This thesis concerns individuals who develop dementia symptoms before 65 years of age (called younger-onset dementia, or YOD) while employed, which has significant personal, financial and social effects due to the commitments and responsibilities of families and work. This thesis aims to identify employment-related work strategies to allow people with dementia to continue to work. Four linked studies consistent with the study aim were designed and implemented. In Chapter 3, Study 1, a review of employer approaches to employees with dementia, evaluated nine studies related to dementia and work. The main analysis extracted, grouped and classified employer actions towards employees with dementia in these studies. Two in three employer responses to employees with dementia were ineffective in supporting employees. Poor understanding of the difficulties of those living with dementia appeared to be the main cause. Better knowledge among individuals experiencing dementia symptoms and their employers is needed. In Chapter 4, Study 2, a review of guidance materials related to dementia in the workplace sought to identify and review the availability, structure and content of information to support employees or employers dealing with dementia. Guidance information published by dementia organisations in English-speaking countries such as Australia, Canada, New Zealand, Singapore, the United Kingdom (England, Scotland and Ireland) and the United States of America was analysed and compiled. Dementia websites were found to offer relevant, high-quality content, but this can be fragmented and difficult to find. Few organisations covered the range of relevant content. Most information was aimed at employees with dementia symptoms rather than their employers. Information gaps for employees with dementia included the importance of early diagnosis and assistive technology applications. Employer information gaps included workplace identification of dementia, employee retention and managing the wider work team around the person with dementia. Chapter 5 addressed Study 3, employer approaches to employees with dementia at work. This chapter extended existing research exploring the experience of dementia at work. Four groups were engaged in semi-structured interviews: (1) employers and human resource (HR) managers; (2) professionals supporting employers such as HR consultants; (3) employees with dementia who were working or had left work within the past two years; and (4) professionals supporting people living with dementia. The study identified employee and employer actions and assessed how dementia could be managed using relevant information and approaches to maintain viable employment. As well as the need for greater awareness of workplace cognitive impairment, this study identified solutions to prolong employment. Suggestions included using relevant expertise and external peer support, implementing self-management and personal strategies, raising employer awareness of employee rights and employer responsibilities, employee engagement in decisions about them and their work and assistance with the transition from work. An analytical approach, considering the person, task and organisation may assist in devising more effective employer implementation approaches. Study 4, guidance model document feedback (presented in Chapter 6), evaluated two model guidance documents (one for employers, the other for employees) developed from Studies 1, 2 and 3. This study aimed to determine the relevance and completeness of the content and identify potential enhancements. Study 3 participants were recontacted for this study. The proposed documents were received positively. Suggested improvements included care in the use of terms such as ‘dementia’, moving beyond ‘dementia friendly’ to inclusivity and clearer specification of the responsibilities of HR practitioners and employers. Chapter 7 placed the findings across the four studies into the context of increased workplace and societal attention to mental health, wellbeing, cognitive fitness and neurodiversity. Growing awareness of these issues is argued to be positive for future workplace understanding, acceptance and management of conditions such as dementia and cognitive impairment. HR leadership and expertise in dealing with dementia in the workplace are pertinent to achieving this goal. This thesis elaborates on the practical importance of information and communication in understanding cognitive impairment at work. Awareness that individuals in the early stages of cognitive difficulties maintain the capacity to continue to work can be improved. A review of information designed to support workplace decision-making has identified content and pathways to improve workplace knowledge and awareness. In conclusion, dementia at work can be managed by integrating awareness of dementia with mental health and cognition in workplaces. Greater attention to the diversity of cognitive abilities and processes in organisations can improve the life experience of employees living with dementia, their contribution to work, overall work performance and satisfaction.
- Description: Doctor of Philosophy
Seeking a destiny in land : the contribution of Scottish settlers to the social development of the Omeo region
- Authors: McCoy, Jennifer
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text: false
- Description: This thesis explores the contribution of Scottish selectors to the social development of the Omeo region of remote eastern Victoria, Australia, during the period 1875 to 1900, drawing on the experiences of people with familial connection to the McCoy family. These people were mostly agricultural labourers, prevented from land ownership in Scotland, and handloom weavers whose skills had been lost to the industrial revolution. Their lives had been changed by economic circumstances in Scotland, and by taking advantage of the Victorian Selection Acts, they achieved economic security while contributing to the development of the area. This thesis positions land as central to the economic and social development of this area. It was a remote, geographically isolated area where communication and climate challenges had defeated many. Using a documentary historical methodology, it examines the impact of each wave of Europeans, explorers, squatters, miners, and selectors on the land, with the corresponding dispossession of Aboriginal people, revealing the agency of those Aboriginal people in their responses, as well as the resilience of the settlers. Land records and demographic data have been used extensively to chart the land holdings and businesses of selected Scottish family members, positioning their place in the developing society, as community centres and activities flourished in response to a secure and growing population. As part of the Scottish diaspora in Australia, it highlights some of the qualities they brought with them to their new environment; it demonstrates the resilience people could bring to challenging circumstances; and it reveals the wealth of creative opportunities that grew and were encouraged, when limited communication to the outside world demanded a call on their own resources. The study also uncovers questions for further research, amongst them: a more detailed investigation of the role of newspapers, which are the primary source of historical information available; and the role played by women in building and supporting families even through crises, and whose records are buried in personal family records or diminished in newspaper stories.
- Description: Doctor of Philosophy
Species pool effects on niche-based island biogeography : insights from the bird communities in Melanesian Archipelagos
- Authors: Olson, Ashley
- Date: 2022
- Type: Text , Thesis , PhD
- Full Text: false
- Description: A fundamental goal of biogeography is to determine how communities of species assemble. Islands offer an excellent opportunity to study community assembly because they have discrete boundaries, their species compliment can be readily quantified, and biogeographic processes operating at broad spatial scales can be separated from the effects of local interactions. Indeed, islands have contributed extensively to the development of biogeographical theory. Historically, the focus of island biogeography studies has been to predict the species richness of their communities. Yet, species richness provides no information about the ecological differences among the species that comprise a community, and thus cannot explain why different types of species do, or do not, appear in island communities. The niche of any particular species represents all of the abiotic and interspecific interactions that determine the survival of that species in a given location. Thus, a niche-based description of island communities differs from a richness-only description as it can link biogeography to the ecological interactions that ultimately drive successful colonisation and evolution on an island. However, island isolation and island area - the key predictors of species immigration and extinction, respectively - and the influence of the composition of the regional species pool have rarely been investigated for their effect on niche differences among species occupying an island. Understanding how the regional species pool, isolation and area influence niche-based diversity on islands provides an important link between biogeography and the ecological interactions that ultimately determine the composition of island communities. I used data on the island birds across Melanesian archipelagos to explore the role of biogeography in driving the niche-based structure of island communities. Specifically, I studied how the composition of the regional species pool, island isolation and island area influence: i) variation in a key functional trait (body size), ii) occupancy and saturation of niches, and iii) the phylogenetic structure of island communities. To do so, I studied three Melanesian archipelagos; the Bismarck, Solomon and Vanuatu islands, each of which represent a separate biogeographic region with a different degree of isolation from the primary source of avian colonists, mainland New Guinea. As such, the influence of oceanic dispersal barriers on the composition of the avifauna of each archipelago can be clearly distinguished. Using this model system, I demonstrate that the effects of island isolation and island area extend beyond determining the number of species on an island to influencing maximum body size, niche occupancy and the phylogenetic structure of island communities. Further, the research I describe in this thesis demonstrates that the influence of island isolation and area on the ecological and evolutionary differences among species that comprise each island community is mediated by the diversity of the regional species pool. Thus, the species observed in island communities, and the niches they occupy, may not be a product of local ecological interactions. Rather, immigration from the regional species pool may determine the persistence of a species on an island.
- Description: Doctor of Philosophy
‘A life less ordinary’ : to downshift or not to downshift : why people make or don’t make decisions to change their lives?
- Authors: Goulding, Carmel
- Date: 2022
- Type: Text , Thesis , PhD
- Full Text: false
- Description: A fundamental condition of modernity is the expansion of choice, with the range of options widening on how we live our lives, and whom we spend our time with. We are no longer defined by a clear set of social ties which bind us to our life situation. We can choose our friends, geographic locality, employment and, perhaps, our gender and that of our children. We can if we choose, substantially alter the way we live, and some people do as is evidenced by the phenomenon popularly known as downshifting. Downshifting involves a voluntary reduction in working time and income, in return for a slower pace of life and increased free time and is generally conceived as a conscious change in ways of consuming, working and relating. This thesis seeks to explore the questions why people downshift and how the decision is sustained over the life course. It does this through a two-staged, longitudinal qualitative study of people who have downshifted in Australia and the United Kingdom. The thesis is built on the assumption that downshifting is a rational choice. People do calculate risk and constraints and the range of options as part of the decision process. However, explanations of action firmly rooted in economic rationality do not adequately account for what influences and shapes preferences and pays little attention to the micro worlds of individual choice-making. This dissertation offers an account of social action built around the concept of bounded rationality whereby the fluid, linked communities evident in modern life, act as a mediating factor in the initial choice and as well as over the downshifter life course. To date, there has been limited empirical research on the life course of downshifters. This doctoral study fills the knowledge gap.
- Description: Doctor of Philosophy
Manifestation of token behaviours on corporate boards; a qualitative study
- Authors: Bhardwaj, Sneh
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text: false
- Description: As boards are central to organisational performance, an ineffective board functioning has long remained a matter of concern among corporate governance researchers, board practitioners, policy makers and the media not only in India – the context of this study – but also across the regions of Asia-Pacific, Africa, Europe, and the Americas. An important aspect of boards’ ineffective working concerns directors’ token board behaviours. This debate in corporate governance circles however continuously adheres to a gender/minority-focused approach, attributing token board behaviours to the gender of minority directors on corporate boards (i.e., women directors). The study aims to examine, firstly, the selection process and criteria for corporate board directors’ appointments in India. Secondly, this thesis examines how the quota appointees are being recruited, integrated, and treated by corporate boards in India, to explain the ensuing participation of quota appointees. The third contribution is (from the third and fourth study aims) a more nuanced explanation of token board behaviours of Indian men and women directors (beyond the commonplace explanation of token board behaviours based on the number of minority directors on corporate boards) from an in-depth examination of directors’ board conduct. The research draws on three theories. Firstly, the resource dependence theory (RDT) lens is used to review the literature on board appointments. RDT supports an argument that board composition impacts board processes, dynamics, and culture, and vice versa. Secondly, the token theory, which identifies the inclusion of minority groups as a perfunctory gesture, is used as a putative explanation for effective/ineffective board participation of directors. Thirdly, the institutional theory is applied to examine the findings related to directors’ quota-based board appointments in response to institutional pressures, namely, coercive, normative, and mimetic. An interpretative phenomenological approach informs this study’s research design. I developed four research questions and, to answer these, conducted twenty-seven semi-structured interviews with Indian board directors to obtain first-hand narration of lived experiences in this context. The findings indicate that a majority of directors consider the pre-, during and post-meeting board dis-engagement, impaired board culture, poorly structured board processes, lacunae in director selection including those of the law-supported women directors and board inexperience of directors as determinants of token behaviour on boards, rather than attributing this understanding to the gender of board minorities alone. These results provide an enhanced understanding of token behaviours manifested by board directors. In so doing, new proposals for restructuring directors’ selection processes, quota law’s implementation, directors’ board roles and boards’ internal functioning are offered. The research has implications for regulators, companies, and governments attempting to enhance the corporate governance effectiveness of corporate boards by putting an end to directors’ token behaviours.
- Description: Doctor of Philosophy
'You Beauty' Alex Jesaulenko An historical exploration of the migrant who became a legend
- Authors: Eddy, Daniel
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text: false
- Description: The Austrian-born Alex Jesaulenko played football in the Victorian Football League (VFL) from 1967 to 1981. His rise to national prominence emerged during a period of great change within both Australian society and Australian rules football. This thesis, through a critical biographical approach, examines for the first time Jesaulenko’s early life, looking at his migrant experience and the role that Australian rules football played in aiding his integration into Australian society. It is not a kick-and-handball analysis of Jesaulenko’s entire football career; that has been extensively covered within copious amounts of primary and secondary sources. Instead, it explores his migrant journey – an important aspect of Jesaulenko’s life which has been largely overlooked – and the key developmental years of sporting education prior to emerging as a VFL champion. It concludes with one of, if not the most, iconic moments in the game’s history: Jesaulenko’s mark in the 1970 VFL grand final, which cemented his name within the Australian sporting consciousness. Australian rules football, and sport more generally, holds a unique place within society. Footballers, it can be argued, are archetypes for our daily dreams and aspirations; exalted figures that we afford status which few will experience in their everyday lives. Therefore, it is through the prism of Jesaulenko’s journey that we can learn more about the role Australian rules football has played for migrants integrating into Australian society.
- Description: Doctor of Philosophy
The Esoteric Osteopath : Thomas Ambrose Bowen (1916-1982) and his contemporaries : exploring influences, networks, creativity and embodiment
- Authors: Strachan, Shirley
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text: false
- Description: This PhD is the first prosopographical study of two generations of Australian manual healers in the twentieth century. The central historical figure is Thomas Ambrose Bowen (1916-1982) a self-titled Australian osteopath and arguably a therapeutic genius turned victim of health politics of the twentieth century. Bowen was stripped of his osteopathic identity as a result of political machinations that occurred during regulation of the industry in the late-1970s and early-1980s. This thesis reveals the legitimacy of Bowen’s claim to osteopathic stature and how his career is representative of the experience of a number of osteopaths during regulation of chiropractic and osteopathy. Bowen’s career was obscured in two respects. Firstly, in the lead up to the Chiropractors and Osteopaths Act 1978, overseas educated interests sought to disenfranchise Australian practitioners. This was offset by a successful response from the Australian chiropractic lobby. Secondly, posthumous commercial popularisation of Bowen’s claimed work, absent observer consensus and historical research, has further served to obfuscate Bowen’s prowess and marginalised his legacy. This thesis is the first to link Bowen’s practice to the influence of F G Roberts, an early Australian pioneer of naturopathic osteopathy. It explores Bowen’s emergence from a network of prominent football masseurs to his professional engagement with osteopathic advocates. This thesis is the first historical study to present the clinical life and times of Bowen among his contemporaries. In doing so it examines his broader significance as a consummate Australian osteopath. New historical narratives founded on extensive primary sources, oral histories as well as discourse analysis, ethnography, biography, hermeneutics and cultural mapping are used to place Bowen in context with his peers on the Australian osteopathic stage. Posthumous narratives that underpin commercial global marketing are challenged to the extent they obscure a clear historical view of Bowen and his marginalised contemporaries as unique actors in their struggle for recognition
- Description: Doctor of Philosophy
A kinship of creatures : Exploring the mutuality of lived experience
- Authors: Ní Shíocháin, Máirín
- Date: 2017
- Type: Text , Thesis , PhD
- Full Text: false
- Description: This practice-led research explores questions of interspecies empathy, mutuality and kinship within the context of visual art. The study is situated broadly within the cross-disciplinary field of Animal Studies and espouses an animal advocacy stance within contemporary arts practice. It addresses concerns about the role of animals in contemporary art and proposes that creating art should not subordinate the ethical treatment of animals. The parameters of this investigation are defined by empathy theory, or Einfühlung. This was deemed an appropriate foundation to underpin the research given its historical association with aesthetic perceptions of works of art as well as empathic responses to other living entities including non-humans. Einfühlung and other contributing conceptual frameworks, including compassionate conservation and animal individuality are thoroughly evaluated in a review of relevant literature. Current arts practice in which the ‘animal’ plays a role is critically examined. The consequences for animals in contemporary art are more often malign than benign and this contrasts with progressive thinking about animal sentience in other areas of philosophical research. In a distillation of the above theoretical concepts, the research further references issues relating to selective application of care for non-human animals, in which the level of consideration is often dependent on human perceptions of the creatures’ status, for example native or introduced animals. The results of the research were revealed through a body of practical work including sculpture, collage, prints and artists’ books which depict a variety of animals and birds, both native and non-native, encountered as part of everyday experience; a visual exploration in which human-perspective classification of animals does not play a part.
- Description: Doctor of Philosophy
Study on complex rock slope stability in large scale open cut mine : Mechanism and evaluation
- Authors: Al Mandalawi, Maged
- Date: 2016
- Type: Text , Thesis , PhD
- Full Text: false
- Description: This thesis is restricted access for an unlimited timeframe and therefore will not be available for public use.
- Description: Doctor of Philosophy
Age estimation and illicit image detection using a stochastic vision model
- Authors: Islam, Mofakharul
- Date: 2013
- Type: Text , Thesis , PhD
- Full Text: false
- Description: The main objective of this research is to investigate and implement a robust approach with a view to provide the Law Enforcement Agencies (LEAs) with a dedicated forensic tool in future for inspecting confiscated PCs from the suspected paedophile to detect pedophilic images automatically and prevent children viewing pornographic and age-inappropriate images at their home and school and adults at their workplace while they are on the Internet. To achieve this goal, we use a novel face descriptor to differentiate child face from adult face based on categorical age specific contextual cues that are based on new knowledge in terms of features or contexts representatives of child and adult face. Given that the craniofacial cues contain enough structural information on visual cues on human face encoded in the form of high level features we can categorize age into adult and children in tandem with low level features. Finally, we will present a novel stochastic vision model based on Markov Random Fields (MRF) prior, which learned the pornographic contextual constraints from the training pornographic images and eventually introduce knowledge on pornography into our proposed stochastic classifier allowing classification of images into pornographic or benign.
- Description: Doctor of Philosophy
Nonsmooth optimization algorithms for clusterwise linear regression
- Authors: Mirzayeva, Hijran
- Date: 2013
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Data mining is about solving problems by analyzing data that present in databases. Supervised and unsupervised data classification (clustering) are among the most important techniques in data mining. Regression analysis is the process of fitting a function (often linear) to the data to discover how one or more variables vary as a function of another. The aim of clusterwise regression is to combine both of these techniques, to discover trends within data, when more than one trend is likely to exist. Clusterwise regression has applications for instance in market segmentation, where it allows one to gather information on customer behaviors for several unknown groups of customers. There exist different methods for solving clusterwise linear regression problems. In spite of that, the development of efficient algorithms for solving clusterwise linear regression problems is still an important research topic. In this thesis our aim is to develop new algorithms for solving clusterwise linear regression problems in large data sets based on incremental and nonsmooth optimization approaches. Three new methods for solving clusterwise linear regression problems are developed and numerically tested on publicly available data sets for regression analysis. The first method is a new algorithm for solving the clusterwise linear regression problems based on their nonsmooth nonconvex formulation. This is an incremental algorithm. The second method is a nonsmooth optimization algorithm for solving clusterwise linear regression problems. Nonsmooth optimization techniques are proposed to use instead of the Sp¨ath algorithm to solve optimization problems at each iteration of the incremental algorithm. The discrete gradient method is used to solve nonsmooth optimization problems at each iteration of the incremental algorithm. This approach allows one to reduce the CPU time and the number of regression problems solved in comparison with the first incremental algorithm. The third algorithm is an algorithm based on an incremental approach and on the smoothing techniques for solving clusterwise linear regression problems. The use of smoothing techniques allows one to apply powerful methods of smooth nonlinear programming to solve clusterwise linear regression problems. Numerical results are presented for all three algorithms using small to large data sets. The new algorithms are also compared with multi-start Sp¨ath algorithm for clusterwise linear regression.
- Description: Doctor of Philosophy
Understanding the Barriers to Improving Occupational Health and Safety in a Medium Sized Business: “An Insider’s View”
- Authors: Teusner, Annabel
- Date: 2013
- Type: Text , Thesis , PhD
- Full Text: false
- Description: Medium sized workplaces are often grouped with small enterprises, yet they can have unique characteristics compared to more intensively studied small and large organisations, however, these differences are often not clearly recognised. The food processing industry is often part of the small and medium sized enterprises (SME) group and has a higher rate of accidents, injury and disease compared with many other industry groups. To improve safety performance in medium enterprises (within the food processing industry), there is a need to identify the perceived barriers to improving OHS amongst managers, supervisors, and process workers. This research provides a unique insider’s point of view of a food packing room within a food manufacturing plant in Melbourne. It is a single case design study, focusing on a specific medium sized enterprise, using insider research and an ethnographic approach to gain a greater understanding of the perceived barriers to improving OHS. The first part of this research focused on understanding the safety culture of the organisation, from different hierarchical perspectives, using Hudson’s Evolution of Safety Cultures model. The second part utilised the Health Belief model to identify the barriers to improving OHS from multiple perspectives of managers, supervisors and process workers. Following the analysis of the results, five barriers were identified: (i) fragmentation of group perspectives; (ii) poor communication between and within the hierarchical groups; (iii) limited OHS training and competency; (iv) inadequate management commitment to OHS; and (v) lack of empowerment. This created tensions amongst and between the groups. However, further examination of these findings suggested a deeper reason for the difficulty in improving the OHS, which was affecting the organisation. The most significant barrier to improving OHS at this workplace was the learned helplessness that had developed over a period of time and had filtered through all hierarchical groups. A reflection on the choice of methodology (insider research) and the importance of ethical considerations and the depth of meaning that was drawn from this research has been presented in this thesis. Learned helplessness has been discussed in the context of a medium sized enterprise and its significance to the contribution to OHS literature. Recommendations have been provided in terms of addressing learned helplessness within a medium sized enterprise, by changing the way individuals think, using learned optimism. Other changes that have been presented have included organisation design, facilitating improved communication and goal setting, and the investigation into the supporting role of supply chains toward OHS initiatives.
- Description: Doctor of Philosophy
Longitudinal data modelling using penalized splines and ranked set sampling
- Authors: Al Kadiri, Mohammad
- Date: 2012
- Type: Text , Thesis , PhD
- Full Text: false
- Description: "Longitudinal studies, where data is collected by measuring the same experimental units several times over a relatively long period, are becoming increasingly common. Conventional statistical approaches have limitations when applied to the analysis of longitudinal data ... Practical limitations of longitudinal analysis that relate to missing data and large data set sizes were explored in this thesis with the application of a sampling technique known as Ranked Set Sampling (RSS). We developed this sampling method, which has not previously been applied to longitudinal data, for fixed and mixed-effects models. This thesis also illustrated inference techniques to estimate these models after selecting sample units by RSS."
- Description: Doctor of Philosophy
Teachers' experiences of the implementation of Teaching Games for Understanding in an Australian Independent secondary school
- Authors: Curry, Christina
- Date: 2012
- Type: Text , Thesis , PhD
- Full Text: false
- Description: With the movement to evolving classroom practices and pedagogies to enhance student-centered learning environments across all Key Learning Areas, there has been growing concern about how educators can produce high quality, intellectual learning experiences within physical education. To provide much-needed understanding of teachers' experiences of the implementation of a TGfU (Teaching Games for Understanding) teaching approach, this study aimed to identify the ways in which individual teachers, adopt, embrace or alternatively resist TGfU as an innovative pedagogy. - Taken from abstract.
- Description: Doctor of Philosophy
The lived experience of security and contentment for latency aged children in shared care, post-separation : a descriptive phenomenological enquiry
- Authors: Sadowski, Christina
- Date: 2012
- Type: Text , Thesis , PhD
- Full Text: false
- Description: "As a result of complex social, economic and legislative factors, the number of children in shared time arrangements (in which children spend equal, or near-equal time, with both parents post-separation) has risen steadily and incrementally in Australia and internationally. Despite the increasing numbers of children in this arrangement, conceptualisations of and discussions about shared care remain largely devoid of children's perspectives about their experiences. As a result, little is known about how children experience this way of living. This study used a descriptive phenomenological approach to explore latency aged (aged 8-12) children's lived experience of security and contentment, and their absence, in a shared care time arrangement." "Interviews were conducted with sixteen children across a diversity of living arrangements (levels of parental cooperation and conflict; self-selected and Court-ordered; day-to-day patterns) who had current or recent experience living in shared care. From this pool of interviews, the eight richest and detailed protocols were selected for descriptive phenomenological analysis. Through a process of detailed analytic exploration of these eight individual descriptions of phenomena under investigation (security and contentment in shared care; the absence of security and contentment in shared care), the core constituents of each phenomenon were discerned. From these, General Structures representing the essence, or the invariants common to all experiences under investigation, were identified. This thesis introduces a child-generated phenomenology of security and contentment, and their absence, in shared care. This phenomenology is based on the careful analysis of children's pre-reflective narrative descriptions, describing core aspects of this arrangement that contribute to their felt security and contentment, and core aspects that compromise it. Ultimately, this thesis presents the child's lived experience of feeling securely shared by parents in the context of a shared time living arrangement. "
- Description: Doctor of Philosophy