List of Titles

Analytical and numerical approaches to evaluate the effect of time-dependent and time-independent soil characteristics on the stability of deep excavations

- Ghadrdan, Mohsen

Authors: Ghadrdan, Mohsen
Date: 2021
Type: Text , Thesis , PhD
Full Text: false
Description: Excavating the ground for different purposes, such as extracting valuable materials or undertaking urban construction, may cause concerns regarding the stability of the formed slopes, which can affect the environment, the economy, and human lives. Slope stability analysis in large-scale and deep excavations such as open-pit mines is challenging due to uncertainties regarding varying material parameters, complex field conditions and lack of or insufficient data such as pore water pressure distribution, in-situ stress conditions, and discontinuities. Despite different advanced analytical and numerical slope stability techniques having been developed, slope stability analysis may produce unreliable conclusions due to these uncertainties and challenges. This study’s objective is to investigate the effect of different factors associated with slope stability through a case study of the Yallourn brown coal open pit mine in Australia. In this study, the two most common slope stability methods—the Limit Equilibrium Method (LEM) and the Finite Element Method (FEM)—were employed. A comprehensive study was conducted to determine how the generation and dissipation of Negative Excess Pore-Water Pressure (NEPWP) affect slope stability assessments. Additionally, due to the complex geological stratigraphy of the site, different scenarios for geological layering were defined and investigated for the slope stability analyses. Moreover, the sensitivity of the slope stability assessment to not only different material characteristics but also different formulations and assumptions of LEM and FEM are presented.
Description: Doctor of Philosophy

A Ballarat chinese family biography – an intergenerational study

- Horsfield, Yvonne

Authors: Horsfield, Yvonne
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: This thesis addresses the gap that has existed in Ballarat’s historiography regarding the historical neglect and ignorance of Chinese family narratives and their life experiences. In doing so this thesis presents a longitudinal, three generational study of an immigrant Ballarat Chinese family from the early 1860s until the 1950s. It examines how members of each Tong Way generation strove to gain acceptance and establish an enduring sense of cultural belonging in a former regional, Victorian gold mining city. An ancestor, Liu Chou Hock, was a sojourner who arrived on the Haddon goldfield in 1862 and successfully worked a claim. Within three years, he returned to his village, Wang Tung, in Taishan, China. His experience was in sharp contrast to that of his son John Tong Way (Liu’ Zongwei) who permanently settled in Ballarat. The family strived to integrate against a background of migrant adjustment, ethnic discrimination and later a policy of assimilation. These factors represented a challenge for all Chinese who remained until the White Australia Policy was abandoned by the Whitlam Labor government in 1973. Unlike Caucasian immigrants, who could assimilate, whilst retaining certain features of their ethnic identification, the Chinese were culturally alienated and often excluded from everyday cultural life and practice. They represented a demographically significant ethnic minority. The thesis also compares the experiences of the Ballarat and Bendigo Chinese communities in order to examine the similarities and differences. In doing so, it analyses how they were able to establish a sense of belonging in their respective communities. The analysis of the Ballarat family’s experiences, combined with that of other Chinese descent families forms the basis of an extended case study. One that argues that adaptation was necessitated by their individual aspirations for acceptance, respectability and success.
Description: Doctor of Philosophy

Conflict and conservation : sharing the costs and benefits of tiger (Panthera tigris) conservation in communities adjacent to tiger reserves in Nepal

- Bhattarai, Babu

Authors: Bhattarai, Babu
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: Human wildlife conflict (HWC) is a highly studied but unresolved aspect of wildlife management. To further knowledge on HWC, this study used a multidisciplinary approach to investigate HWC implications for local people living adjacent to two key tiger conservation reserves in Nepal. The study also assessed the potential to redistribute financial benefits accruing from predator conservation to those bearing costs through associated HWC. Secondary data and anecdotal reports suggest that local people experience significant direct and indirect costs from predator conservation through livestock losses following attacks by common leopards and Bengal tigers, and additionally, crop losses due to their prey species plus two mega herbivores (elephant and one-horned rhinoceros). To investigate this situation, data regarding HWC incidents and costs were sourced through interviews with 422 local households, direct observations, and stakeholder interviews. Collected data included livestock loss (5-year time-period) and crop loss (1-year time-period). Complementary direct observation data collated livestock loss and crop damage for 12 months. Interviews were conducted also with park visitors (N=387) and tourism business owners (N=74). Results showed that tigers are involved in significantly fewer depredation events compared to leopards. Leopards predominantly killed small to medium livestock whereas tigers selected both small to medium and large sized livestock. Livestock depredation events occurred more frequently in livestock corrals relative to forest zones or crop fields. Rates of livestock losses per household per year self-reported during interviews with local people were found higher when compared to those observed by direct measurement. Prey species of tigers and leopards (most often wild boar and chital) were involved in more frequently in crop raiding events, and caused more crop damage, when compared that caused by mega herbivores. Quantities of crops lost per household were lowest in communities where effective physical barriers to wildlife were present. Park visitors and tourism business owners indicated willingness to pay for conservation of tigers and for compensation of farmers for the losses caused by tigers and their prey species. Study findings support several key recommendations proposed to mitigate negative HWC effects in the study area. These include financial support for local communities to build predator proof livestock corrals and establishment of effective physical barriers at the park borders. A dedicated tariff for park visitors and a levy for tourism business owners are also recommended to fund ongoing predator conservation and support financial compensation for local farmers affected by HWC.
Description: Doctor of Philosophy

Exploring the interior : performing situated responsibility in postcolonising Australia

- Berger, Karen

Authors: Berger, Karen
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: Theatre is a powerful way to investigate the operation of borders due to its live, immediate focus on representation and its potential to test a society’s boundaries. This practice-led research incorporates a performance and an exegesis to ask, ‘How can site-specific theatre that investigates the performance of borders and heterotopia enhance understanding of individual responsibility in postcolonising Australia?’ I take the term postcolonising from Aileen Moreton-Robinson, who argues that the beneficiaries of settler-colonialism (such as myself) must accept responsibility for the past before attempting to address its injustices. As an artist, I am inspired by anthropologist, Deborah Bird Rose, who privileges storytelling as a way of breaking boundaries between the past and present. Michel Foucault coined the term heterotopia (other place) to denote a single real space that juxtaposes several sites that are incompatible. This evokes the contemporary Australian situation of contested sovereignty. As Joanne Tompkins argues, heterotopic theatre can enact such a space in order to raise awareness and work towards societal change. My research demonstrates this both theoretically and practically. My exegesis crosses borders to create a heterotopia by juxtaposing past, present and possible futures, stories and theoretical understandings from diverse sources. The performance created at my home, rather than in a theatre, layers family, local, Australian and international histories to highlight the continuum between the personal and political, and to question current structures of power and knowledge. I use site-specific theatre to diminish the boundaries between performer and audience, creating a visceral heterotopia that facilitates a deeper understanding of personal responsibility in the context of postcolonising Australia.
Description: Doctor of Philosophy

FEM and XFEM approaches to Investigate the Hydromechanical Interactions within a jointed soft-rock slope

- Shaghaghi, Tahereh

Authors: Shaghaghi, Tahereh
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: One of the most significant challenges of open-cut mining is to provide stability for the excavated slopes. Unrealistic predictions of the slopes’ behaviour during and after mining operations can lead to the failure of slopes, and this may pose a threat to human lives, the economy, and the environment. By excavating soft rock masses in open-cut mines, pre-existing joints can open and new joints can form behind excavated slopes. This phenomenon is due to the geotechnical character of the materials and stress relief movements of the excavated slopes. The stability of slopes in the rock masses is significantly influenced by the existence of discontinuities such as joints. The water flows in the opened joints can change the pore water pressure distribution in the slopes. The interaction between the joints and the water may impose different loading scenarios on the open-cut mines and put the safety of mining operations at risk. The analysis of slope stability can become more complicated because of the presence of water, discontinuities, and their interaction within the slopes in open-cut mines. This study investigates the hydromechanical interactions in the saturated jointed slopes due to pore water pressure changes. The second-largest open-cut mine in Australia, the Yallourn brown coal open-cut mine located in Victoria, was chosen as the case study for this research. In this study, several coupled pore fluid diffusion and stress-strain analyses are conducted using the extended finite element method (XFEM) in conjunction with the finite element method (FEM). This study firstly examines a joint aperture and pore water pressure changes of the excavated jointed slope due to installing a drainage system and backfilling in front of the slope. Secondly, a series of sensitivity analyses are carried out on the pore water pressure distribution changes to the variation of the permeability magnitude of the material and leakage properties of the joint surfaces. Finally, to control the pore water pressure of the saturated jointed slope, a series of drainage systems is designed. The arrangement and length of the drains are optimised by conducting a series of sensitivity analyses on the leakage properties of the joint and the permeability of the soft rock.
Description: Doctor of Philosophy

Imbalanced data classification and its application in cyber security

- Moniruzzaman, Md

Authors: Moniruzzaman, Md
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: Cyber security, also known as information technology security or simply as information security, aims to protect government organizations, companies and individuals by defending their computers, servers, electronic systems, networks, and data from malicious attacks. With the advancement of client-side on the fly web content generation techniques, it becomes easier for attackers to modify the content of a website dynamically and gain access to valuable information. The impact of cybercrime to the global economy is now more than ever, and it is growing day by day. Among various types of cybercrimes, financial attacks are widely spread and the financial sector is among most targeted. Both corporations and individuals are losing a huge amount of money each year. The majority portion of financial attacks is carried out by banking malware and web-based attacks. The end users are not always skilled enough to differentiate between injected content and actual contents of a webpage. Designing a real-time security system for ensuring a safe browsing experience is a challenging task. Some of the existing solutions are designed for client side and all the users have to install it in their system, which is very difficult to implement. In addition, various platforms and tools are used by organizations and individuals, therefore, different solutions are needed to be designed. The existing server-side solution often focuses on sanitizing and filtering the inputs. It will fail to detect obfuscated and hidden scripts. This is a realtime security system and any significant delay will hamper user experience. Therefore, finding the most optimized and efficient solution is very important. To ensure an easy installation and integration capabilities of any solution with the existing system is also a critical factor to consider. If the solution is efficient but difficult to integrate, then it may not be a feasible solution for practical use. Unsupervised and supervised data classification techniques have been widely applied to design algorithms for solving cyber security problems. The performance of these algorithms varies depending on types of cyber security problems and size of datasets. To date, existing algorithms do not achieve high accuracy in detecting malware activities. Datasets in cyber security and, especially those from financial sectors, are predominantly imbalanced datasets as the number of malware activities is significantly less than the number of normal activities. This means that classifiers for imbalanced datasets can be used to develop supervised data classification algorithms to detect malware activities. Development of classifiers for imbalanced data sets has been subject of research over the last decade. Most of these classifiers are based on oversampling and undersampling techniques and are not efficient in many situations as such techniques are applied globally. In this thesis, we develop two new algorithms for solving supervised data classification problems in imbalanced datasets and then apply them to solve malware detection problems. The first algorithm is designed using the piecewise linear classifiers by formulating this problem as an optimization problem and by applying the penalty function method. More specifically, we add more penalty to the objective function for misclassified points from minority classes. The second method is based on the combination of the supervised and unsupervised (clustering) algorithms. Such an approach allows one to identify areas in the input space where minority classes are located and to apply local oversampling or undersampling. This approach leads to the design of more efficient and accurate classifiers. The proposed algorithms are tested using real-world datasets. Results clearly demonstrate superiority of newly introduced algorithms. Then we apply these algorithms to design classifiers to detect malwares.
Description: Doctor of Philosophy

Impact of workplace guanxi on knowledge sharing and innovative work behaviour : a study of academic staff of Chinese local universities in Guangdong Province

- Liu, Li

Authors: Liu, Li
Date: 2020
Type: Text , Thesis , PhD
Full Text: false
Description: This thesis aims to investigate the impact of workplace guanxi upon knowledge sharing and innovative work behaviour. Knowledge sharing and innovative work behaviour are two behavioural variables which have been linked to various positive individual and organisational outcomes. Against the changing landscape of Chinese higher education, the two behaviours are particularly important for the success of Chinese academic staff and the local universities where they work. Extant literature has demonstrated that workplace interpersonal relationships such as leader-member exchange and team-member exchange are positively associated with individual’s work behaviours, such as knowledge sharing and innovative work behaviour. However, there is a scant literature on the impact of workplace guanxi upon the two workplace behaviours. Using conservation of resource theory and social exchange theory, this research conceptualised a structural model to study the impact of workplace guanxi upon knowledge sharing and innovative work behaviour. A positivist approach with cross-sectional design and structural equation modelling was adopted to test the conceptualised model. Data were extracted from 479 academic staff of seven local universities in Guangdong Province of China, through selfreport questionnaire. A positive relationship was found between coworker guanxi and knowledge sharing. In contrast, no relationship was found between supervisor-subordinate guanxi and knowledge sharing. The relationship between coworker guanxi and knowledge sharing was fully mediated by teammember exchange and job satisfaction. In terms of innovative work behaviour, both supervisorsubordinate guanxi and coworker guanxi displayed a positive relationship with innovative work behaviour. Coworker guanxi showed a stronger relationship with innovative work behaviour than supervisor-subordinate guanxi did. The relationship between supervisorsubordinate guanxi and innovative work behaviour was direct. The relationship between coworker guanxi and innovative work behaviour was indirect, with full mediation of teammember exchange, job satisfaction and knowledge sharing. This thesis contributes to the literature on explaining the role of workplace guanxi, including supervisor-subordinate guanxi and coworker guanxi on knowledge sharing and innovative work behaviour. The study also demonstrates to higher education institute managers that the cultivation of academic staff’s workplace guanxi, and particularly their guanxi with peer academics, promotes academic staff’s displays of knowledge sharing and innovative work behaviour which are beneficial at both individual and organisational levels within the higher education context.
Description: Doctor of Philosophy

The effects of norepinephrine on the proliferation, lipid-uptake and mRNA expression of inflammatory markers in vascular smooth muscle cells

- Anesi, Jack

Authors: Anesi, Jack
Date: 2020
Type: Text , Thesis , Master of Applied Science
Full Text: false
Description: Background: Cardiovascular disease (CVD) is the leading, global cause of death. Elevated levels of norepinephrine (NE) are associated with CVDs such as coronary heart disease with atherosclerosis as the underlying mechanism. Oxidised low-density lipoprotein (OxLDL) has been shown to play an integral role in the formation of atherosclerosis within the vasculature. Previous studies suggest a decrease in NE by renal denervation is associated with enhanced atherosclerosis in mice and NE has anti-inflammatory effects. Therefore, we hypothesised that NE may protect against atherosclerosis. This study aimed to investigate the effects of NE on cellular proliferation, OxLDL uptake and mRNA expression of inflammatory markers in mouse aortic vascular smooth muscle cells (VSMCs), a key cell type involved in atherosclerosis. Methods: Mouse aortic VSMCs were cultured and treated with NE for three consecutive days. Cell proliferation was measured using the trypan blue exclusion and MTS proliferation assays. VSMCs were exposed to fluorescence-labelled OxLDL in the presence or absence of NE for 24 hours. Cellular uptake of fluorescence-labelled OxLDL was visualised by confocal microscopy and analysed for mean fluorescence intensity using ImageJ. To investigate the involvement of NE receptors, the
Description: Masters

'You Beauty' Alex Jesaulenko An historical exploration of the migrant who became a legend

- Eddy, Daniel

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

A case study of teacher roles in engaging with student aspirations

- Walker, Amy

Authors: Walker, Amy
Date: 2019
Type: Text , Thesis , PhD
Full Text: false
Description: This thesis investigated the complex role teachers play, both formally and informally, in relation to engaging and supporting student aspirations. Due to the links that have been established between aspirations and school completion and involvement in tertiary education, aspirations are important in an educational context. Yet, despite the abundance of aspiration related research, most has focused on student or parent perspectives, with few scholars targeting teacher perceptions of their roles in relation to student aspirations. This research is therefore significant as it addresses this gap through a single case study investigating perceptions of P-12 teachers from a peri-urban independent school in Victoria, Australia. Data were collected from 57 teachers via survey, interviews, and school document analysis. A lens of research-as-bricoleur, incorporating the theoretical frameworks of Bronfenbrenner (1979; 1994), Turner (2001), Gottfredson (1981, 1996), and Patton and McMahon (2015), provided the interpretative basis for the applied thematic analysis of the different data sets. Findings demonstrated differences in the way that teachers conceptualised their role in engaging with student aspirations. While teacher participants identified various formal and informal roles that they played in relation to engaging student aspirations, they also reported a lack of clear guidance or guidelines, necessitating the development of personal processes to direct their involvement. Other important findings highlighted a number of factors that teacher participants perceived as facilitating or impeding possible roles they could play in engaging student aspirations. The understandings emanating from this research provide substantive assistance to stakeholders, including school administrators and teacher educators, in appreciating and appropriately responding to an area of practice which remains misunderstood and without clear policy or guidelines. Ultimately, this research adds to the growing body of research into student aspirations and the concomitant importance of teachers in helping students aspire to and achieve their goals.
Description: Doctor of Philosophy

Neural malware detection

- Park, Sean

Authors: Park, Sean
Date: 2019
Type: Text , Thesis , PhD
Full Text: false
Description: At the heart of today’s malware problem lies theoretically infinite diversity created by metamorphism. The majority of conventional machine learning techniques tackle the problem with the assumptions that a sufficiently large number of training samples exist and that the training set is independent and identically distributed. However, the lack of semantic features combined with the models under these wrong assumptions result largely in overfitting with many false positives against real world samples, resulting in systems being left vulnerable to various adversarial attacks. A key observation is that modern malware authors write a script that automatically generates an arbitrarily large number of diverse samples that share similar characteristics in program logic, which is a very cost-effective way to evade detection with minimum effort. Given that many malware campaigns follow this paradigm of economic malware manufacturing model, the samples within a campaign are likely to share coherent semantic characteristics. This opens up a possibility of one-to-many detection. Therefore, it is crucial to capture this non-linear metamorphic pattern unique to the campaign in order to detect these seemingly diverse but identically rooted variants. To address these issues, this dissertation proposes novel deep learning models, including generative static malware outbreak detection model, generative dynamic malware detection model using spatio-temporal isomorphic dynamic features, and instruction cognitive malware detection. A comparative study on metamorphic threats is also conducted as part of the thesis. Generative adversarial autoencoder (AAE) over convolutional network with global average pooling is introduced as a fundamental deep learning framework for malware detection, which captures highly complex non-linear metamorphism through translation invariancy and local variation insensitivity. Generative Adversarial Network (GAN) used as a part of the framework enables oneshot training where semantically isomorphic malware campaigns are identified by a single malware instance sampled from the very initial outbreak. This is a major innovation because, to the best of our knowledge, no approach has been found to this challenging training objective against the malware distribution that consists of a large number of very sparse groups artificially driven by arms race between attackers and defenders. In addition, we propose a novel method that extracts instruction cognitive representation from uninterpreted raw binary executables, which can be used for oneto- many malware detection via one-shot training against frequency spectrum of the Transformer’s encoded latent representation. The method works regardless of the presence of diverse malware variations while remaining resilient to adversarial attacks that mostly use random perturbation against raw binaries. Comprehensive performance analyses including mathematical formulations and experimental evaluations are provided, with the proposed deep learning framework for malware detection exhibiting a superior performance over conventional machine learning methods. The methods proposed in this thesis are applicable to a variety of threat environments here artificially formed sparse distributions arise at the cyber battle fronts.
Description: Doctor of Philosophy

Regeneration of sulfur rich amines in a combined capture system aimed to lower the cost of PCC in Australian coal fired power plants

- Garg, Bharti

Authors: Garg, Bharti
Date: 2019
Type: Text , Thesis , PhD
Full Text: false
Description: Coal is the dominant and most reliable source of energy in Australia. However, the increasing global temperatures and its impact on the climate raises concerns on the use of coal worldwide. Due to availability of abundant, cheap quality coals, Australia is researching how it and its international customers can continue to use its abundant coal resources whilst limiting greenhouse emissions. Hence, low CO2 emitting energy technologies like carbon capture and storage (CCS) have an important role to play not only in power but also the cement and steel industries Post-combustion CO2 capture (PCC), the most developed technology in CCS using aqueous amines to capture CO2, still face challenges for its large-scale commercialisation. The cost of electricity with PCC rises to almost double that produced without integrating PCC technology in new power stations. The retrofit of PCC technology into existing power stations is very site specific and costs can be around half of the cost of building a new power plant. Apart from this, the implementation of PCC poses an energy penalty to the power station as the efficiency of the plant can drop almost by 10-11% due to the increased solvent heating and CO2 compression loads. Particularly with the nations like Australia, the cost of PCC installation is even higher as there are no flue gas desulfurisation (FGD) units in Australian power stations. The presence of harmful gases like SO2 in coal-fired power plant flue gases affect CO2 capture performance during PCC due to the higher affinity of amines to absorb stronger acidic gases against CO2 which is a weaker acid gas than SO2. These stronger acidic gases tend to form heat stable salts with the absorbent amines used to capture CO2 . Heat stable salts refer to the thermally non-regenerable protonated amines which are usually produced when the amine solution is contaminated by organic acids (Weiland et al., 2004). Hence, the bonded amine is not available for CO2 capture, increasing the requirement for makeup amine resulting in higher operating cost. Therefore, FGD units are an essential requirement before the installation of PCC facilities in a coal-fired power station. This results in a levelised cost of electricity in Australian power plants that is high compared to nations which have FGD installed in their power stations. CSIRO has developed a combined capture process to simultaneously capture CO2 and SO2 from Australian power plant flue gases using a single amine absorbent in order to lower the cost of PCC installation in Australia. The process generates a unique sulfur rich amine absorbent which needs regeneration. This thesis investigates various amine regeneration processes, using MEA as a reference, and their commercial viability to the CS-Cap process. Due to the unique nature of the sulfur rich absorbent generated in the CS-Cap process, its amine is recoverable through many other regeneration processes besides standard thermal reclamation. My thesis investigates the effectiveness of regeneration techniques like Ion exchange, Electro-dialysis, Crystallisation, Nano-filtration in regenerating the sulfur rich amine. Initially the theoretical investigation was carried as a part of literature review and further a brief exploratory laboratory scale evaluation of the most suited technologies was carried out. The results obtained from laboratory scale experimentation were fed to an Aspen Plus simulation model in order to understand the behaviour of the system under various operating conditions. Further a cost estimation was carried out in order to produce a high level cost for the selected regeneration technologies in the CS-Cap process. The cost of the regeneration technologies were further integrated into the overall CO2 capture process in order to compare the cost of standard FGD + PCC process against the CS-Cap process which answers the broader research question whether the CS-Cap process will be economical for Australian coal power plants. Overall this thesis reveals the effectiveness of various technologies in regenerating sulfur rich amines. It suggests CSIRO’s patented CS-Cap process is a cost-effective approach for capturing CO2 from Australian coal fired power plants despite its sensitivity to regeneration cost.
Description: Doctor of Philosophy

The role of Zn2+ in insulin signalling and muscle atrophy

- Maier, Michelle

Authors: Maier, Michelle
Date: 2019
Type: Text , Thesis , PhD
Full Text: false
Description: Zn2+ is a broadly utilised ion in biology that has important catalytic, structural and regulatory roles within the cell. Zn2+ distribution in cells is maintained by zinc transporters, Zips and ZnTs, and disruptions in levels of Zn2+ have been associated with insulin resistance and muscle atrophy disorders. Zn2+ and reactive oxygen species (ROS) interact through inhibition of protein tyrosine phosphatases and ROS-mediated oxidation of the metal-binding metallothioneins (Mts) causing release of bound Zn2+, however the precise mechanisms are unclear. In the first study of this thesis addition of inhibitors of ROS-generating enzymes, superoxide dismutase 1 (SOD1) and NADPH oxidase 1 (NOX1) showed that only SOD1 inhibition increased short-term insulin-mediated Zn2+ release and increased the expression of Mt1 and 2. These results may suggest that ROS, in particular O2- accumulation through inhibition of SOD1, plays a role in insulin-mediated Zn2+ release. Inhibiting SOD1 prevents the conversion of O2- to H2O2 causing an accumulation of O2- in the cell which oxidises Mts to release Zn2+, thereby increasing Zn2+ levels within the cell. Manipulation of the expression of the zinc transporter Zip-7 has previously been shown to modulate cell signalling and glucose metabolism in C2C12 skeletal muscle cells, warranting further investigation into the role of Zn2+ within insulin signalling. Reducing Zip-7 expression when NOX1 was inhibited caused a decrease in Mt2 expression in response to insulin suggesting an interaction between insulin, Zip-7 and NOX1 activity but this requires further investigation. Skeletal muscle atrophy is a clinical symptom of insulin resistance and diabetes. Muscle atrophy is associated with increases in circulating glucocorticoid levels and accumulation of Zn2+ in muscle. This study investigates if Zn2+ homeostasis is disrupted in glucocorticoid-induced atrophy using C2C12 skeletal muscle cells treated with Dexamethasone (DEX) and iv insulin. Results demonstrate DEX-induced atrophy significantly increased the gene expression of the Mt1&2 and decreased glycogen accumulation when treated with insulin. Both confocal microscopy and flow cytometry showed significant increases in free cellular Zn2+ after DEX treatment. Notably, free Zn2+ levels observed with confocal microscopy increased after insulin treatment in control cells but decreased in DEX treated cells. Total cellular Zn2+ was increased by DEX treatment. This demonstrates that DEX causes Zn2+ accumulation in muscle cells and disrupts both Zn2+ homeostasis through blocking insulin-induced Zn2+ release, and insulin-induced glycogen synthesis. This raised the question of whether the same effects of atrophy on Zn2+ homeostasis apply to other cell systems. To investigate this, we examined adipose cells given that these too are involved in insulin resistance and muscle atrophy disorders. In this study we found similar increases in mRNA abundance of Mt1 & 2. Confocal microscopy revealed that DEX treatment caused changes in the distribution of free Zn2+ within peri-nuclear and cytosolic regions of the cell upon stimulation with insulin. Furthermore, investigation into morphometric changes using Oil Red O staining and particle analysis through Coherent Anti-Stokes Ramen Spectrophotometry (CARS) microscopy showed changes in cell and lipid droplet size consistent with reduced lipid turnover in DEX treated cells. These results highlight a potential mechanistic role for Zn2+ in the development of atrophy in 3T3-L1 adipocytes where increased free Zn2+ and its redistribution in cells may inhibit lipid metabolism downstream of insulin signalling. These findings show that insulin-induced Zn2+ release is disrupted by glucocorticoids and this is associated with insulin resistance. Restoring control of Zn2+ homeostasis, possibly through controlling oxidation or manipulating Zn2+ levels directly, may prove beneficial in metabolic disease states such as diabetes.
Description: Doctor of Philosophy

Three-dimensional numerical study on the batter instability mechanism of Maddingley Brown Coal Open Pit, Victoria, Australia using PLAXIS 3D

- Zhao, Lei

Authors: Zhao, Lei
Date: 2019
Type: Text , Thesis , PhD
Full Text: false
Description: With the increased size of excavation due to long-term open cut mining, batter instability has become a major geo-hazard in Victorian Brown Coal Open Pits where facilitate some largest brown coal mining operations in the world. Block failure is a unique failure mode in Victorian brown coal mines, which is often associated with cracks and rainfall. Maddingley Brown Coal Mine (MBC) is located in Bacchus Marsh, Victoria, Australia. Slope instability has also been a major geo-problem since the open pit mining commenced in MBC in 1940s. Making clear the cracking mechanism and the correlations between rainfall and batter instability have important implications in better understanding and predicting batter failures in Victorian brown coal mines. In this research, three-dimensional geologic models were developed to investigate the mechanism of brown coal batter instability. The finite element program encoded in Plaxis 3D was employed to conduct the complex two-phase (fluid-solid) coupled numerical simulations. The results revealed the cracking mechanism of coal batter and the effects of rainfall on batter stability. It was found that the brown coal batter with overburden tends to lead a circular critical path while the batter after overburden removal shows a trend of block sliding as interpreted by the shear and tensile strains simulated. The existence of joints and the hydrostatic water pressure in the joints could adversely affect the stability of brown coal batter towards block failure. Precipitation can increase the deformation, excess pore pressure, total pore pressure, active pressure and decrease the matric suction, and thereby decrease the shear strength, effective stress, and batter stability. The results from the three-dimensional hydro-mechanically coupled finite element study were well agreed with the field monitored data, theoretical calculations, and Victorian brown coal mining experience.
Description: Doctor of Philosophy

Characterisation of the deformation behaviour of unbound granular materials using repeated load triaxial testing

- Zhalehjoo, Negin

Authors: Zhalehjoo, Negin
Date: 2018
Type: Text , Thesis , PhD
Full Text: false
Description: Unbound Granular Materials (UGMs) are used in the base/subbase layers of flexible pavements for the majority of roads around the world. The deterioration of pavements increases with the increase of traffic loadings. To ensure the long-term performance and serviceability of pavement structures through a realistic design, the precise evaluation and comprehensive characterisation of the resilient and permanent deformation behaviour of pavement materials are essential. The present PhD study aims to investigate the characterisation of the resilient and permanent deformation behaviour of four road base UGMs sourced from quarries in Victoria, Australia, using Repeated Load Triaxial (RLT) testing. The triaxial system used in this study is instrumented with four axial deformation measurement transducers to achieve highly precise measurements and to evaluate the effect of instrumentation on the resilient modulus of UGMs. The resilient Poisson’s ratio of the studied UGMs is also determined using a radial Hall-Effect transducer. Moreover, a series of permanent deformation tests is performed to precisely characterise the axial and radial permanent deformation behaviour of UGMs and investigate the factors that may significantly influence the accumulated axial and radial permanent deformations. Finally, three permanent deformation models incorporated with a time-hardening procedure are employed to predict the magnitude of permanent strain for multiple stress levels of the RLT test. The predictions using the employed models are then compared against the measured values to evaluate the suitability of the models and to identify the model that best predicts the strain accumulation behaviour of the tested UGMs. While this study focuses on the resilient and permanent deformation behaviour of four Victorian UGMs under repeated loading, the knowledge generated from this comprehensive investigation will contribute towards the global development of more reliable methods for evaluating the long-term performance of pavement structures and minimising road maintenance and repair costs.
Description: Doctor of Philosophy

Lime stabilisation of an Australian silty clay and its application in construction of excavation retaining walls by cutter soil mixing

- Ranjbar Pouya, Kaveh

Authors: Ranjbar Pouya, Kaveh
Date: 2018
Type: Text , Thesis , PhD
Full Text: false
Description: Coode Island Silt (CIS) is one of the predominant geological units in Melbourne, Australia. Having high compressibility and low shear strength, CIS is considered a problematic soft soil that challenges the construction of infrastructure in the region. To tackle such challenges, one practical approach is the application of ground improvement techniques such as in situ soil mixing. This PhD study focuses on the application of Cutter Soil Mixing (CSM) for the construction of excavation retaining walls in CIS. Although cement is widely used in most CSM projects, this study investigates the suitability of different lime types available in the Australian market as a potential alternative to cement for the stabilisation of CIS. To investigate the effect of lime stabilisation, a comprehensive geotechnical characterisation of untreated and lime treated CIS is performed. Four different lime types are used: agricultural lime, quicklime, hydrated lime and slag lime. Based on the results obtained from strength tests, slag lime was found to be the most effective among the four types that were tested. The optimum slag lime to CIS ratio is then found for the construction of retaining walls in CIS. Having the geotechnical characterisation of untreated and treated CIS from the laboratory experiments, a series of two-dimensional and three-dimensional finite element method (FEM) analyses were conducted to investigate the applicability and reliability of the selected mixing ratio for the construction of CSM excavation retaining walls in CIS. A nonlinear constitutive soil model was employed, calibrated and verified to be used in FEM analyses to investigate both the stability factor of safety and excavation-induced deformations. The results obtained for both undrained and fully coupled flow deformation analyses prove that CSM panels can be constructed by mixing slag lime and CIS to act as retaining walls to allow for deep excavation in CIS.
Description: Doctor of Philosophy

A kinship of creatures : Exploring the mutuality of lived experience

- Ní Shíocháin, Máirín

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

The assumed divide : Examining gender, feminism and relationships through visual art

- Hollis, Sylvia

Authors: Hollis, Sylvia
Date: 2017
Type: Text , Thesis , Masters
Full Text: false
Description: The Assumed Divide is a visual arts based, practice-led research project which explores expectations of gender within the context of interpersonal relationships, structured through feminist theory. I created a collection of small, figurative sculptures inspired by experiences of animosity and misunderstanding, to locate areas of gendered interpersonal ambivalence. This thesis proposes that feminism might enhance gender relations by deconstructing harmful stereotypes and by encouraging empathy and respect for diversity. Issues such as reproductive choice, intergenerational debate, and uncertainty in aims are discussed as apparent impediments to the unity of feminism, against a patriarchal tradition that grants men categorical universality. I argue that by dismantling the perception of male unification and by elucidating the multitudinous similarities and variances of human experience, feminism makes advances in eliminating sexism. I also examine how binary gender division, with an assumption of distinct difference between male and female, generates conflict and power dynamics advantageous to men, diminishing the quality of heterosexual and social relationships. The observation that overlapping gender traits blur boundaries of male and female, and that rigid categorisations are not indisputably representative of all people, may offer more points of connection to bridge the divide of gender. Each artwork in The Assumed Divide reflects on gendered experience, with sculpted depictions of disintegrated flesh acting as visual manifestations of the psyches and social conditions of the figures. Working realistically on a small scale, and integrating found silver trays as motifs of domesticity and relationships, my intent is to directly stimulate contemplation of the themes in context to viewers’ lives, recognising that the audience is free to find their own meaning in the works. Discussion of these pieces, alongside works by other artists who broach topics of feminism, gender, and relationships, exemplifies the capacity for art to infuse theory with personal insight, inspired and derived from the lives of both artist and viewer.
Description: Masters by Research

Multiple perspectives on the development of a safe school culture within a new educational setting : a case study of cultural change in a Prep to Year 12 school in regional Victoria

- Iles, Lyndsey

Authors: Iles, Lyndsey
Date: 2014
Type: Text , Thesis , EdD
Full Text: false
Description: "This thesis explores the impact of the implementation and embedding of the Restorative Practices philosophy and practices into a Year Prep to Year Twelve College in Victoria from the perspective of the students, staff and community members. The amalgamation of a number of small regional primary, specialist and secondary schools in 2005 resulted in a less than satisfactory consolidated school environment. Students and staff reported that they felt unsafe in the new college, and that, consequently, the opportunities for learning were severely compromised. The school and community were thus required to attempt a reinvigoration of the school culture to meet the needs of the students and staff of the new college. It was found that within the context of developing a safe and supportive learning environment, relationships were central to the new approaches towards learning. In this process, it was found that the notion of cultural change became intertwined with the building of relationships between students and students, and students and staff. Thus, this study centred on understanding, from a case study perspective, how the approaches developed by this school for behaviour management have changed over the duration of the research, and how the iterative process of cultural change reflected a growing awareness among staff of the key issues in promoting mutual respect across the whole school.
Description: Doctor of Education

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