Analytical and numerical approaches to evaluate the effect of time-dependent and time-independent soil characteristics on the stability of deep excavations
- Authors: Ghadrdan, Mohsen
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- 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
- Authors: Ghadrdan, Mohsen
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- 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
Applicability of LAMP as a field diagnostic test for haemonchus contortus and fasciola hepatica infection
- Authors: Bari, Tanjina
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Gastrointestinal parasites Haemonchus contortus and Fasciola hepatica are major impediments to livestock production worldwide. Faecal egg counts remain the most commonly used and widely accepted diagnostic tool for these parasites; however, there is a need for improved, field-applicable diagnostics. In this study, loop-mediated isothermal amplification (LAMP) was optimised and evaluated for the detection of H. contortus (in sheep) and F. hepatica (in cattle) infection. LAMP assays were optimised to enable visual detection using calcein dye. DNA extraction techniques were developed that have the potential for on-farm application. Faeces suspended in water, heated, then centrifuged, with two cheap and stable chemicals, enabled detection of H. contortus at clinically relevant infection burdens. For F. hepatica, a faeces-water suspension was sieved to remove particulate matter, then physical disruption (bead-beating) was applied. LAMP was conducted under laboratory conditions and in the field; compared to FEC (the most commonly used diagnostic for the target parasites) and PCR. LAMP was conducted using three incubation methods: a commercially available thermocycler; a field-friendly low-cost portable styrofoam esky; and a dedicated field applicable LAMP incubator. The general trend was for LAMP to have high sensitivity but only moderate specificity when compared to FEC. However, the use of PCR (both pathogens) and a highly sensitive amended FEC (F. hepatica only) suggested that the apparent low specificity was the result of LAMP being able to detect low-level parasite infection when conventional FEC could not. A LAMP assay paired with a potentially field-applicable DNA extraction was able to adequately detect haemonchosis at ‘clinically relevant’ parasite burdens in a laboratory study. A field study for the detection of F. hepatica demonstrated the potential utility of LAMP on-farm. The studies conducted in this thesis demonstrate the potential of LAMP for parasitic disease diagnosis in agriculture.
- Description: Doctor of Philosophy
- Authors: Bari, Tanjina
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Gastrointestinal parasites Haemonchus contortus and Fasciola hepatica are major impediments to livestock production worldwide. Faecal egg counts remain the most commonly used and widely accepted diagnostic tool for these parasites; however, there is a need for improved, field-applicable diagnostics. In this study, loop-mediated isothermal amplification (LAMP) was optimised and evaluated for the detection of H. contortus (in sheep) and F. hepatica (in cattle) infection. LAMP assays were optimised to enable visual detection using calcein dye. DNA extraction techniques were developed that have the potential for on-farm application. Faeces suspended in water, heated, then centrifuged, with two cheap and stable chemicals, enabled detection of H. contortus at clinically relevant infection burdens. For F. hepatica, a faeces-water suspension was sieved to remove particulate matter, then physical disruption (bead-beating) was applied. LAMP was conducted under laboratory conditions and in the field; compared to FEC (the most commonly used diagnostic for the target parasites) and PCR. LAMP was conducted using three incubation methods: a commercially available thermocycler; a field-friendly low-cost portable styrofoam esky; and a dedicated field applicable LAMP incubator. The general trend was for LAMP to have high sensitivity but only moderate specificity when compared to FEC. However, the use of PCR (both pathogens) and a highly sensitive amended FEC (F. hepatica only) suggested that the apparent low specificity was the result of LAMP being able to detect low-level parasite infection when conventional FEC could not. A LAMP assay paired with a potentially field-applicable DNA extraction was able to adequately detect haemonchosis at ‘clinically relevant’ parasite burdens in a laboratory study. A field study for the detection of F. hepatica demonstrated the potential utility of LAMP on-farm. The studies conducted in this thesis demonstrate the potential of LAMP for parasitic disease diagnosis in agriculture.
- Description: Doctor of Philosophy
Applied aspirations : design and applied art at the Ballarat Technical Art School during the early twentieth century
- Authors: Whetter, Elise
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Applied art and design schools operate at the nexus of art, industry, and education. During the early decades of the twentieth century, the regionally located Ballarat Technical Art School (BTAS) was the leading institution of its kind in Victoria, Australia, amid shifting economic, cultural, and pedagogical conditions. Emerging from a 1907 amalgamation of institutions, and subsequently administrated by the School of Mines Ballarat (SMB), BTAS was equipped with the assets, experience, and historic reputation necessary to surpass its provincial and metropolitan rivals. This micro-historical case-study employs qualitative analysis of primary sources to investigate the aims, outputs, and importance of BTAS, contextualised by the expectations and influences it operated under during the inaugural principalship of artist and educator, Herbert Henry Smith. Smith oversaw the training of designers, craftspeople, artists, and teachers from 1907 until his retirement in early 1940—a period of tumultuous events, fiscal obstacles, and social and cultural debate. The institution was accountable to diverse stakeholders and arbiters of taste, and successive cohorts learned in a contested space between tradition, origination, and modernisation. Pierre Bourdieu’s cultural theory serves to navigate this web of hierarchies, assumptions, and tensions, while secondary sources help contextualise findings. This thesis also discusses the suite of drawing, design and material-based disciplines delivered at BTAS as single subjects, full courses, and supplementary art-trade training. Throughout, featured students provide examples of regionally trained, Australian designer-maker and artist-teacher experiences. BTAS students learned from ambitious and skilled men and women, benefited from strong professional networks, and fostered a notable esprit-de-corps. The school was significant for its contribution to female technical training. The school’s pre-eminent position was modified during the late 1920s, when much art and art-teacher training was re-centred in Melbourne. Yet, the valuable, compelling, and widespread influence of Ballarat Technical Art School graduates resonated for decades.
- Description: Doctor of Philosophy
- Authors: Whetter, Elise
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Applied art and design schools operate at the nexus of art, industry, and education. During the early decades of the twentieth century, the regionally located Ballarat Technical Art School (BTAS) was the leading institution of its kind in Victoria, Australia, amid shifting economic, cultural, and pedagogical conditions. Emerging from a 1907 amalgamation of institutions, and subsequently administrated by the School of Mines Ballarat (SMB), BTAS was equipped with the assets, experience, and historic reputation necessary to surpass its provincial and metropolitan rivals. This micro-historical case-study employs qualitative analysis of primary sources to investigate the aims, outputs, and importance of BTAS, contextualised by the expectations and influences it operated under during the inaugural principalship of artist and educator, Herbert Henry Smith. Smith oversaw the training of designers, craftspeople, artists, and teachers from 1907 until his retirement in early 1940—a period of tumultuous events, fiscal obstacles, and social and cultural debate. The institution was accountable to diverse stakeholders and arbiters of taste, and successive cohorts learned in a contested space between tradition, origination, and modernisation. Pierre Bourdieu’s cultural theory serves to navigate this web of hierarchies, assumptions, and tensions, while secondary sources help contextualise findings. This thesis also discusses the suite of drawing, design and material-based disciplines delivered at BTAS as single subjects, full courses, and supplementary art-trade training. Throughout, featured students provide examples of regionally trained, Australian designer-maker and artist-teacher experiences. BTAS students learned from ambitious and skilled men and women, benefited from strong professional networks, and fostered a notable esprit-de-corps. The school was significant for its contribution to female technical training. The school’s pre-eminent position was modified during the late 1920s, when much art and art-teacher training was re-centred in Melbourne. Yet, the valuable, compelling, and widespread influence of Ballarat Technical Art School graduates resonated for decades.
- Description: Doctor of Philosophy
Approaches to learning : perceptions about Chinese international undergraduates in Australian Universities
- Li, Boli
- Authors: Li, Boli
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Chinese students constitute the largest cohort of international undergraduates in Australian universities, comprising 37.3% in 2019. However, there is a scarcity of research examining perceptions of how Chinese international students (CIS) learn in Australian universities, from the broader context of the students themselves, their Australian teachers and Australian domestic student (ADS) counterparts. Drawing on the 3P (Presage-Process-Product) framework by Biggs, Kember, and Leung (2001), this thesis explored the perceptions of CIS, and their lecturers and classmates regarding their approaches to learning in Australian universities. Utilising a mixed methods approach (Creswell, 2014), surveys were conducted with 156 CIS and 212 ADS incorporating a validated survey by Biggs et al. (2001) called the R-SPQ-2F. Interviews were also conducted with 10 CIS and 10 Australian academics from two Australian universities, one regional and the other metropolitan. The findings demonstrated that perceptions of CIS were characterised by a unique learning structure that differed from ADS in a number of ways, particularly in relation to group learning, the use of understanding and memorisation strategies, and classroom engagement. It was noted that these disparities did not support the generally held view of CIS as mainly surface oriented learners who preferred rote-learning techniques (Grimshaw, 2007). While adopting similar levels to ADS of deep approach strategies in their learning, CIS also used more surface and achieving approaches than ADS, and tended to incorporate memorising with understanding in their learning process. However, it was also evident that the approaches used by CIS in Australia were often more complex than what was easily observed. For instance, their reticence in class was not necessarily indicative of passive learning, but instead, suggestive of the complexity of context that needs to encompass the ‘whole being’ of these students, i.e., their personality, culture, and most of all, the dynamics of their perceived approaches to their learning. This study also investigated negotiations that occurred between CIS and their Australian lecturers. While CIS’ learning approaches were greatly shaped and determined by academics’ instructional decisions involving curriculum, teaching patterns and assessment procedures, it was also found that academics’ instructional activities were reshaped and counter-determined by CIS’ learning approaches. As a result, a Co-constructed Model of Learning and Teaching (CMLT) for CIS in Australian universities, based on the 3P framework (Biggs et al., 2001), was developed to assist future education experiences for international students. This study is significant in that it has given voice to Chinese students, enabling a greater understanding of their experiences in Australian universities to emerge, in conjunction with and supplemented by insights provided by their Australian student counterparts and educators. It has enabled both international and domestic students the opportunity to reflect on possible cultural impacts on learning, hopefully improving their capacities to act as effective global citizens. It has also afforded an opportunity for academics to reflect on their beliefs and practices in relation to teaching diverse student cohorts, which will hopefully deepen their understanding of the complexities that come with the increasing globalisation of education.
- Description: Doctor of Philosophy
- Authors: Li, Boli
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Chinese students constitute the largest cohort of international undergraduates in Australian universities, comprising 37.3% in 2019. However, there is a scarcity of research examining perceptions of how Chinese international students (CIS) learn in Australian universities, from the broader context of the students themselves, their Australian teachers and Australian domestic student (ADS) counterparts. Drawing on the 3P (Presage-Process-Product) framework by Biggs, Kember, and Leung (2001), this thesis explored the perceptions of CIS, and their lecturers and classmates regarding their approaches to learning in Australian universities. Utilising a mixed methods approach (Creswell, 2014), surveys were conducted with 156 CIS and 212 ADS incorporating a validated survey by Biggs et al. (2001) called the R-SPQ-2F. Interviews were also conducted with 10 CIS and 10 Australian academics from two Australian universities, one regional and the other metropolitan. The findings demonstrated that perceptions of CIS were characterised by a unique learning structure that differed from ADS in a number of ways, particularly in relation to group learning, the use of understanding and memorisation strategies, and classroom engagement. It was noted that these disparities did not support the generally held view of CIS as mainly surface oriented learners who preferred rote-learning techniques (Grimshaw, 2007). While adopting similar levels to ADS of deep approach strategies in their learning, CIS also used more surface and achieving approaches than ADS, and tended to incorporate memorising with understanding in their learning process. However, it was also evident that the approaches used by CIS in Australia were often more complex than what was easily observed. For instance, their reticence in class was not necessarily indicative of passive learning, but instead, suggestive of the complexity of context that needs to encompass the ‘whole being’ of these students, i.e., their personality, culture, and most of all, the dynamics of their perceived approaches to their learning. This study also investigated negotiations that occurred between CIS and their Australian lecturers. While CIS’ learning approaches were greatly shaped and determined by academics’ instructional decisions involving curriculum, teaching patterns and assessment procedures, it was also found that academics’ instructional activities were reshaped and counter-determined by CIS’ learning approaches. As a result, a Co-constructed Model of Learning and Teaching (CMLT) for CIS in Australian universities, based on the 3P framework (Biggs et al., 2001), was developed to assist future education experiences for international students. This study is significant in that it has given voice to Chinese students, enabling a greater understanding of their experiences in Australian universities to emerge, in conjunction with and supplemented by insights provided by their Australian student counterparts and educators. It has enabled both international and domestic students the opportunity to reflect on possible cultural impacts on learning, hopefully improving their capacities to act as effective global citizens. It has also afforded an opportunity for academics to reflect on their beliefs and practices in relation to teaching diverse student cohorts, which will hopefully deepen their understanding of the complexities that come with the increasing globalisation of education.
- Description: Doctor of Philosophy
Biopsychosocial Data Analytics and Modeling
- Authors: Santhanagopalan, Meena
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Sustained customisation of digital health intervention (DHI) programs, in the context of community health engagement, requires strong integration of multi-sourced interdisciplinary biopsychosocial health data. The biopsychosocial model is built upon the idea that biological, psychological and social processes are integrally and interactively involved in physical health and illness. One of the longstanding challenges of dealing with healthcare data is the wide variety of data generated from different sources and the increasing need to learn actionable insights that drive performance improvement. The growth of information and communication technology has led to the increased use of DHI programs. These programs use an observational methodology that helps researchers to study the everyday behaviour of participants during the course of the program by analysing data generated from digital tools such as wearables, online surveys and ecological momentary assessment (EMA). Combined with data reported from biological and psychological tests, this provides rich and unique biopsychosocial data. There is a strong need to review and apply novel approaches to combining biopsychosocial data from a methodological perspective. Although some studies have used data analytics in research on clinical trial data generated from digital interventions, data analytics on biopsychosocial data generated from DHI programs is limited. The study in this thesis develops and implements innovative approaches for analysing the existing unique and rich biopsychosocial data generated from the wellness study, a DHI program conducted by the School of Science, Psychology and Sport at Federation University. The characteristics of variety, value and veracity that usually describe big data are also relevant to the biopsychosocial data handled in this thesis. These historical, retrospective real-life biopsychosocial data provide fertile ground for research through the use of data analytics to discover patterns hidden in the data and to obtain new knowledge. This thesis presents the studies carried out on three aspects of biopsychosocial research. First, we present the salient traits of the three components - biological, psychological and social - of biopsychosocial research. Next, we investigate the challenges of pre-processing biopsychosocial data, placing special emphasis on the time-series data generated from wearable sensor devices. Finally, we present the application of statistical and machine learning (ML) tools to integrate variables from the biopsychosocial disciplines to build a predictive model. The first chapter presents the salient features of the biopsychosocial data for each discipline. The second chapter presents the challenges of pre-processing biopsychosocial data, focusing on the time-series data generated from wearable sensor devices. The third chapter uses statistical and ML tools to integrate variables from the biopsychosocial disciplines to build a predictive model. Among its other important analyses and results, the key contributions of the research described in this thesis include the following: 1. using gamma distribution to model neurocognitive reaction time data that presents interesting properties (skewness and kurtosis for the data distribution) 2. using novel ‘peak heart-rate’ count metric to quantify ‘biological’ stress 3. using the ML approach to evaluate DHIs 4. using a recurrent neural network (RNN) and long short-term memory (LSTM) data prediction model to predict Difficulties in Emotion Regulation Scale (DERS) and primary emotion (PE) using wearable sensor data.
- Description: Doctor of Philosophy
- Authors: Santhanagopalan, Meena
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Sustained customisation of digital health intervention (DHI) programs, in the context of community health engagement, requires strong integration of multi-sourced interdisciplinary biopsychosocial health data. The biopsychosocial model is built upon the idea that biological, psychological and social processes are integrally and interactively involved in physical health and illness. One of the longstanding challenges of dealing with healthcare data is the wide variety of data generated from different sources and the increasing need to learn actionable insights that drive performance improvement. The growth of information and communication technology has led to the increased use of DHI programs. These programs use an observational methodology that helps researchers to study the everyday behaviour of participants during the course of the program by analysing data generated from digital tools such as wearables, online surveys and ecological momentary assessment (EMA). Combined with data reported from biological and psychological tests, this provides rich and unique biopsychosocial data. There is a strong need to review and apply novel approaches to combining biopsychosocial data from a methodological perspective. Although some studies have used data analytics in research on clinical trial data generated from digital interventions, data analytics on biopsychosocial data generated from DHI programs is limited. The study in this thesis develops and implements innovative approaches for analysing the existing unique and rich biopsychosocial data generated from the wellness study, a DHI program conducted by the School of Science, Psychology and Sport at Federation University. The characteristics of variety, value and veracity that usually describe big data are also relevant to the biopsychosocial data handled in this thesis. These historical, retrospective real-life biopsychosocial data provide fertile ground for research through the use of data analytics to discover patterns hidden in the data and to obtain new knowledge. This thesis presents the studies carried out on three aspects of biopsychosocial research. First, we present the salient traits of the three components - biological, psychological and social - of biopsychosocial research. Next, we investigate the challenges of pre-processing biopsychosocial data, placing special emphasis on the time-series data generated from wearable sensor devices. Finally, we present the application of statistical and machine learning (ML) tools to integrate variables from the biopsychosocial disciplines to build a predictive model. The first chapter presents the salient features of the biopsychosocial data for each discipline. The second chapter presents the challenges of pre-processing biopsychosocial data, focusing on the time-series data generated from wearable sensor devices. The third chapter uses statistical and ML tools to integrate variables from the biopsychosocial disciplines to build a predictive model. Among its other important analyses and results, the key contributions of the research described in this thesis include the following: 1. using gamma distribution to model neurocognitive reaction time data that presents interesting properties (skewness and kurtosis for the data distribution) 2. using novel ‘peak heart-rate’ count metric to quantify ‘biological’ stress 3. using the ML approach to evaluate DHIs 4. using a recurrent neural network (RNN) and long short-term memory (LSTM) data prediction model to predict Difficulties in Emotion Regulation Scale (DERS) and primary emotion (PE) using wearable sensor data.
- Description: Doctor of Philosophy
Care leavers recovering voice and agency through counter-narratives
- Authors: Golding, Frank
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The publications in this thesis discuss recurring issues in the historical context of out-of-home Care (OOHC). They were written for various audiences but are arranged not by date of publication but thematically so as to present a coherent argument about the recovery of voice and agency by those who experienced OOHC. The thesis begins with an Overview which discusses autoethnographic and multi-layered approaches to history and shows how subject matter helps determine the choice of methodology and sources and, in turn, how methodologies influence the selection of sources and shape content. Authorities in Australia have a long history of removing children from their families when they are deemed to be neglected or ‘in moral danger’. Out of the public gaze, these children were often rendered silent, their voices simply unheard or deliberately supressed by the exercise of total institutional power. This thesis analyses how children were marginalised, cast as ‘the other’, and framed as deserving no better than they got. In the aftermath of a series of inquiries into institutional child maltreatment—some of which came about as a result of survivor advocacy and relied heavily on direct testimony—we now better understand children’s institutional experiences. In this changing environment, advocacy groups are effectively challenging the received accounts of historical Care. Their challenge has gained impetus from the opening up of records through rights legislation, especially access to personal case files. Large numbers of Care leavers have found their files inaccurate, incomplete, or misleading, and this discovery has stimulated many to produce compelling counter-narratives of the lived experiences of their childhood, and the living experiences that endure. The thesis concludes with an extended analytical commentary reflecting new interpretations of emerging histories, assessing changes in the status of Care leavers, and identifying directions warranting further development in OOHC.
- Description: Doctor of Philosophy
- Authors: Golding, Frank
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The publications in this thesis discuss recurring issues in the historical context of out-of-home Care (OOHC). They were written for various audiences but are arranged not by date of publication but thematically so as to present a coherent argument about the recovery of voice and agency by those who experienced OOHC. The thesis begins with an Overview which discusses autoethnographic and multi-layered approaches to history and shows how subject matter helps determine the choice of methodology and sources and, in turn, how methodologies influence the selection of sources and shape content. Authorities in Australia have a long history of removing children from their families when they are deemed to be neglected or ‘in moral danger’. Out of the public gaze, these children were often rendered silent, their voices simply unheard or deliberately supressed by the exercise of total institutional power. This thesis analyses how children were marginalised, cast as ‘the other’, and framed as deserving no better than they got. In the aftermath of a series of inquiries into institutional child maltreatment—some of which came about as a result of survivor advocacy and relied heavily on direct testimony—we now better understand children’s institutional experiences. In this changing environment, advocacy groups are effectively challenging the received accounts of historical Care. Their challenge has gained impetus from the opening up of records through rights legislation, especially access to personal case files. Large numbers of Care leavers have found their files inaccurate, incomplete, or misleading, and this discovery has stimulated many to produce compelling counter-narratives of the lived experiences of their childhood, and the living experiences that endure. The thesis concludes with an extended analytical commentary reflecting new interpretations of emerging histories, assessing changes in the status of Care leavers, and identifying directions warranting further development in OOHC.
- Description: Doctor of Philosophy
Challenges faced by early-career researchers in the sciences in Australia and the consequent effect of those challenges on their careers : a mixed methods project
- Authors: Christian, Katherine
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The purpose of the study was to explore the challenges faced by early-career researchers (ECRs) in the sciences in Australia and the consequent effect of those challenges on their careers. Using a realist/postpositivist paradigm, an evaluative approach, and a framework of job satisfaction, this project has explored and compared the views of ECRs to evaluate the factors which shape the ECR experience and contribute to job satisfaction or dissatisfaction and intention to leave, and to define the features which are necessary to keep an ECR in research. Data collection for this mixed methods study entailed a national survey of researchers working in universities and research institutes (n=658), a focus group discussion and semistructured in-depth interviews with eight women from a variety of scientific disciplines who had recently left academic research workplaces. I focussed particularly on the difficulties consequent to job insecurity: the constant need to attracting funding and a permanent position, lack of work-life balance and associated stress; and evidence of workplace difficulties such as bullying, harassment or inequity and support – or lack of it – offered by the research institutions. I examined the factors which contribute to and barriers which prevent job satisfaction of this population, and the consequent intention (if any) for ECRs to leave research or change their career path. I found an interesting situation whereby the satisfaction derived from a “love of science” was counterbalanced by stress and poor working conditions which are a consequence of lack of job security, typified by poor supervision, bullying or harassment, inequitable hiring practices, a concerning rate of impact from “questionable research practices” (impacting 34%-41% of respondents) and evidence of very high (80%) intention of ECRs to leave their position. The most significant predictor of intention to leave is time as a postdoctoral scientist: eventually the job insecurity and its associated stresses become too much and the ECRs leave their chosen career for work elsewhere. This decision, too, provides interesting findings as many of the ECRs have difficulty planning what to do next. They feel ill-prepared for an alternate career and suffer from a sense of failure as a result of having to leave academia. While addressing the shortage of funding is outside the scope of this study, in addition to offering my findings I put forward a range of recommendations which could lead to ar change of culture and benefit the wellbeing of ECRs in STEMM without incurring significant cost. The Australian Government, higher education institutions and the research community need to improve job security and workplace conditions and take better care of our people in STEMM disciplines or we will not have the scientists we need to deliver the “innovative Australia” planned for 2030 (Department of Industry Innovation and Science, 2018)
- Description: Doctor of Philosophy
- Authors: Christian, Katherine
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The purpose of the study was to explore the challenges faced by early-career researchers (ECRs) in the sciences in Australia and the consequent effect of those challenges on their careers. Using a realist/postpositivist paradigm, an evaluative approach, and a framework of job satisfaction, this project has explored and compared the views of ECRs to evaluate the factors which shape the ECR experience and contribute to job satisfaction or dissatisfaction and intention to leave, and to define the features which are necessary to keep an ECR in research. Data collection for this mixed methods study entailed a national survey of researchers working in universities and research institutes (n=658), a focus group discussion and semistructured in-depth interviews with eight women from a variety of scientific disciplines who had recently left academic research workplaces. I focussed particularly on the difficulties consequent to job insecurity: the constant need to attracting funding and a permanent position, lack of work-life balance and associated stress; and evidence of workplace difficulties such as bullying, harassment or inequity and support – or lack of it – offered by the research institutions. I examined the factors which contribute to and barriers which prevent job satisfaction of this population, and the consequent intention (if any) for ECRs to leave research or change their career path. I found an interesting situation whereby the satisfaction derived from a “love of science” was counterbalanced by stress and poor working conditions which are a consequence of lack of job security, typified by poor supervision, bullying or harassment, inequitable hiring practices, a concerning rate of impact from “questionable research practices” (impacting 34%-41% of respondents) and evidence of very high (80%) intention of ECRs to leave their position. The most significant predictor of intention to leave is time as a postdoctoral scientist: eventually the job insecurity and its associated stresses become too much and the ECRs leave their chosen career for work elsewhere. This decision, too, provides interesting findings as many of the ECRs have difficulty planning what to do next. They feel ill-prepared for an alternate career and suffer from a sense of failure as a result of having to leave academia. While addressing the shortage of funding is outside the scope of this study, in addition to offering my findings I put forward a range of recommendations which could lead to ar change of culture and benefit the wellbeing of ECRs in STEMM without incurring significant cost. The Australian Government, higher education institutions and the research community need to improve job security and workplace conditions and take better care of our people in STEMM disciplines or we will not have the scientists we need to deliver the “innovative Australia” planned for 2030 (Department of Industry Innovation and Science, 2018)
- Description: Doctor of Philosophy
Characterising MAIT cells in human mucosal cancers
- Authors: Kelly, Jason
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Mucosal associated invariant T cells (MAIT cells) are MR1-restricted T cells that regulate the local immune milieu with cytotoxic and cytokine responses. MAIT cells are well-known for their antimicrobial properties but are also of interest in mucosal cancers, such as colorectal cancer (CRC) and lung cancer (LC). These cancers arise in tissues that provide a barrier to the gut-resident microbiota that can potentially stimulate MAIT cells. Previous studies established that MAIT cells are present within CRC tissues, but there has been contradictory evidence about their significance within these tumour tissues. For example, their cytokine response may promote tumour elimination; however, the high frequencies of MAIT cells within CRC correlate with poor prognostic outcomes, suggesting they may be detrimental in these cancers. Despite the interest in MAIT cells within these tumours, little is known about their location, activation status and cytokine potential within the neoplastic tissue. Chapter 1 of this project investigated human circulating MAIT cells in both CRC and LC patients, finding a significant reduction in the frequency of circulating MAIT cells in the LC patient cohort. We also investigated the frequency and location of MAIT cells within non-cancerous colorectal tissues, identifying that MAIT cells are frequent in the sub-epithelial dome of gut-associated lymphoid tissue (GALT). In contrast, MAIT cells are frequent in the inflammatory response at the tumour margin in CRC tissues. Chapter 2 of this project investigated MAIT cell activation within the CRC tumour environment, with CD25 analysis identifying that MAIT cells appeared to be selectively activated within CRC tissue. We then sought to identify which cells within CRC tissue can present the cognate MAIT cell antigen, finding that CRC cells can take up soluble antigen, upregulate MR1 to the cell surface, and activate MAIT cells. However, these experiments identified a yet to be characterised soluble product secreted by CRC cells that appears to suppress MAIT cell TNF expression after encountering antigen. Chapter 3 of this project investigated MAIT cell responses after chronic (> 2 weeks) stimulation via TCR signalling, a condition likely to be found in both CRC tissue and pre-cancerous lesions, as these lesions are associated with mucosal barrier defects that allow microbes within the gut lumen to transit the barrier. These investigations found a novel, mixed Th1/Th2 cytokine response that included prodigious IL-13 expression. We found that the IL-13 produced by chronically stimulated MAIT cells was sufficient to signal to CRC cells and induce CRC cell transcriptional changes via the STAT6 pathway. Collectively, the findings of our study have provided new insights about the significance of MAIT cells in CRC and highlighted them as a potential target for immunotherapies to improve anti-tumour immunity in mucosal tissues.
- Description: Doctor of Philosophy
- Authors: Kelly, Jason
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Mucosal associated invariant T cells (MAIT cells) are MR1-restricted T cells that regulate the local immune milieu with cytotoxic and cytokine responses. MAIT cells are well-known for their antimicrobial properties but are also of interest in mucosal cancers, such as colorectal cancer (CRC) and lung cancer (LC). These cancers arise in tissues that provide a barrier to the gut-resident microbiota that can potentially stimulate MAIT cells. Previous studies established that MAIT cells are present within CRC tissues, but there has been contradictory evidence about their significance within these tumour tissues. For example, their cytokine response may promote tumour elimination; however, the high frequencies of MAIT cells within CRC correlate with poor prognostic outcomes, suggesting they may be detrimental in these cancers. Despite the interest in MAIT cells within these tumours, little is known about their location, activation status and cytokine potential within the neoplastic tissue. Chapter 1 of this project investigated human circulating MAIT cells in both CRC and LC patients, finding a significant reduction in the frequency of circulating MAIT cells in the LC patient cohort. We also investigated the frequency and location of MAIT cells within non-cancerous colorectal tissues, identifying that MAIT cells are frequent in the sub-epithelial dome of gut-associated lymphoid tissue (GALT). In contrast, MAIT cells are frequent in the inflammatory response at the tumour margin in CRC tissues. Chapter 2 of this project investigated MAIT cell activation within the CRC tumour environment, with CD25 analysis identifying that MAIT cells appeared to be selectively activated within CRC tissue. We then sought to identify which cells within CRC tissue can present the cognate MAIT cell antigen, finding that CRC cells can take up soluble antigen, upregulate MR1 to the cell surface, and activate MAIT cells. However, these experiments identified a yet to be characterised soluble product secreted by CRC cells that appears to suppress MAIT cell TNF expression after encountering antigen. Chapter 3 of this project investigated MAIT cell responses after chronic (> 2 weeks) stimulation via TCR signalling, a condition likely to be found in both CRC tissue and pre-cancerous lesions, as these lesions are associated with mucosal barrier defects that allow microbes within the gut lumen to transit the barrier. These investigations found a novel, mixed Th1/Th2 cytokine response that included prodigious IL-13 expression. We found that the IL-13 produced by chronically stimulated MAIT cells was sufficient to signal to CRC cells and induce CRC cell transcriptional changes via the STAT6 pathway. Collectively, the findings of our study have provided new insights about the significance of MAIT cells in CRC and highlighted them as a potential target for immunotherapies to improve anti-tumour immunity in mucosal tissues.
- Description: Doctor of Philosophy
Developing chiropractic students clinical practice skills - elements of best practice : a qualitative exploratory descriptive study
- Authors: Haworth, Navine
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background Although chiropractic has 125 years as an established profession, scrutiny of the literature proves that few studies have examined the clinical education of chiropractic students with a call for research from academics. This thesis is significant as it develops knowledge that can inform chiropractic bodies and help them improve an essential component of chiropractic education: clinical skill development. Research Purpose and Aims The purpose of this study was to identify elements of best practices in clinical education by critically examining, exploring and describing the aspects of an exemplar chiropractic clinical program that develops students’ clinical practice skills for transition into practice. This study explored the innovative clinical program of a reputable American chiropractic institution providing a scaffolded clinical program across varied clinical settings, patient populations and amongst other health disciplines. Research Design A six-phase exploratory descriptive qualitative design (EDQD) study was conducted to explore and describe the phenomenon being examined (Flick, 2014). This design enabled the collection of information about perceptions and lived experiences of three stakeholder cohorts: clinical faculty members, students and new graduates. Methods Purposive sampling (of students and clinical faculty members) and snowball sampling techniques (of new graduates) were used to derive the sample. Data were collected in three cycles across a two-year period using in-depth, semi-structured interviews. Interviews were conducted with 15 clinical faculty members and eight new graduates, and semi-structured focus groups were conducted with 20 students. All data were audio recorded, transcribed and thematically analysed using an inductive approach. Findings Chiropractic clinical education programs ought to be developed within a framework that incorporates adult learner principles; situated, social and experiential learning theories. Valued was a student-centred learning experience that includes authentic and diverse clinical placements, supervision and mentoring from multiple clinical educators which enhances students’ access to varied perspectives of clinical practices that contributes to developing clinical skills and professional identity. Business knowledge and entrepreneurial skills was an area of deficiency, which is problematic when the objective is to build graduates’ independence in clinical practice and professional prospects are predominantly private practice (NBCE, 2020). Embedding evidence-based practice within curricula and clinical training for educators and students are necessary to ensure this becomes a part of clinical practice. Conclusion This thesis posits best practice in chiropractic clinical education consists of the following: (a) using a scaffolded longitudinal clinical program, (b) varying clinical placements and case mix, (c) supervision and mentoring from multiple clinical educators, (d) educating the clinical educator, (e) curricula designed around industry standards and desired graduate attributes and capabilities, (f) an evidence-based practice approach in the curricula and clinical context, (g) aligning business skills, knowledge and practices with the professional context and (h) interprofessional learning and practice opportunities. Although this study has made a contribution to scholarly discourse, there remain many gaps in our knowledge where further studies are needed.
- Description: Doctor of Philosophy
- Authors: Haworth, Navine
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background Although chiropractic has 125 years as an established profession, scrutiny of the literature proves that few studies have examined the clinical education of chiropractic students with a call for research from academics. This thesis is significant as it develops knowledge that can inform chiropractic bodies and help them improve an essential component of chiropractic education: clinical skill development. Research Purpose and Aims The purpose of this study was to identify elements of best practices in clinical education by critically examining, exploring and describing the aspects of an exemplar chiropractic clinical program that develops students’ clinical practice skills for transition into practice. This study explored the innovative clinical program of a reputable American chiropractic institution providing a scaffolded clinical program across varied clinical settings, patient populations and amongst other health disciplines. Research Design A six-phase exploratory descriptive qualitative design (EDQD) study was conducted to explore and describe the phenomenon being examined (Flick, 2014). This design enabled the collection of information about perceptions and lived experiences of three stakeholder cohorts: clinical faculty members, students and new graduates. Methods Purposive sampling (of students and clinical faculty members) and snowball sampling techniques (of new graduates) were used to derive the sample. Data were collected in three cycles across a two-year period using in-depth, semi-structured interviews. Interviews were conducted with 15 clinical faculty members and eight new graduates, and semi-structured focus groups were conducted with 20 students. All data were audio recorded, transcribed and thematically analysed using an inductive approach. Findings Chiropractic clinical education programs ought to be developed within a framework that incorporates adult learner principles; situated, social and experiential learning theories. Valued was a student-centred learning experience that includes authentic and diverse clinical placements, supervision and mentoring from multiple clinical educators which enhances students’ access to varied perspectives of clinical practices that contributes to developing clinical skills and professional identity. Business knowledge and entrepreneurial skills was an area of deficiency, which is problematic when the objective is to build graduates’ independence in clinical practice and professional prospects are predominantly private practice (NBCE, 2020). Embedding evidence-based practice within curricula and clinical training for educators and students are necessary to ensure this becomes a part of clinical practice. Conclusion This thesis posits best practice in chiropractic clinical education consists of the following: (a) using a scaffolded longitudinal clinical program, (b) varying clinical placements and case mix, (c) supervision and mentoring from multiple clinical educators, (d) educating the clinical educator, (e) curricula designed around industry standards and desired graduate attributes and capabilities, (f) an evidence-based practice approach in the curricula and clinical context, (g) aligning business skills, knowledge and practices with the professional context and (h) interprofessional learning and practice opportunities. Although this study has made a contribution to scholarly discourse, there remain many gaps in our knowledge where further studies are needed.
- Description: Doctor of Philosophy
Discovering Smeaton : people, trade and finance, a study of imperialism and its heritage
- Authors: Just, Alan
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Using Anderson’s Mill in the Victorian goldfield township of Smeaton as a case study, this thesis examines how the process of colonisation can be understood through the study of local history in the context of its imperial heritage. It also examines the transition of Crown sovereignty to colonial sovereignty in Victoria during the second half of the nineteenth century. This thesis explores the proposition that by discovering the history of Smeaton through the era of John Anderson, it is possible to trace how the Victorian gold rushes and the imperial legacy shaped the emerging Australian nation and constructions of identity during the era when the doctrine of terra nullius prevailed. The thesis sets out the argument that the history of Anderson's Mill and the township of Smeaton provides an original perspective into the Australian colonisation process, particularly in the colony of Victorian. It also contends that the Victorian gold rushes altered the balance of an imperial power struggle that influenced the colonial foundations of notions of sovereignty. This was underpinned by finance and trade, which were the driving forces that transferred the notion of empire through to local colonial communities. What emerges in this thesis is a critical narrative of colonial Victoria, which highlights the particular dynamic tension that was present between the colony and the imperial centre through a sharp focus on Anderson’s Mill and Smeaton, its associated townships.
- Description: Doctor of Philosophy
- Authors: Just, Alan
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Using Anderson’s Mill in the Victorian goldfield township of Smeaton as a case study, this thesis examines how the process of colonisation can be understood through the study of local history in the context of its imperial heritage. It also examines the transition of Crown sovereignty to colonial sovereignty in Victoria during the second half of the nineteenth century. This thesis explores the proposition that by discovering the history of Smeaton through the era of John Anderson, it is possible to trace how the Victorian gold rushes and the imperial legacy shaped the emerging Australian nation and constructions of identity during the era when the doctrine of terra nullius prevailed. The thesis sets out the argument that the history of Anderson's Mill and the township of Smeaton provides an original perspective into the Australian colonisation process, particularly in the colony of Victorian. It also contends that the Victorian gold rushes altered the balance of an imperial power struggle that influenced the colonial foundations of notions of sovereignty. This was underpinned by finance and trade, which were the driving forces that transferred the notion of empire through to local colonial communities. What emerges in this thesis is a critical narrative of colonial Victoria, which highlights the particular dynamic tension that was present between the colony and the imperial centre through a sharp focus on Anderson’s Mill and Smeaton, its associated townships.
- Description: Doctor of Philosophy
Early intervention to reduce young peoples’ contact with the criminal justice system : local knowledge to inform practice
- Authors: Lancefield, Kay
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The involvement of youth in justice systems generates high social and economic costs for individuals, their families and communities. Although Victorian crime statistics indicate a decline in youth offending there remains a subgroup who persist, resulting in adverse outcomes. Despite considerable scholarly attention on the factors that contribute to youth contact with justice systems, the application of this knowledge in some instances has failed to reduce such contact and deliver the desired outcomes. This thesis asserts that the factors relat ing to youth contact with justice systems are best understood within the theoretical frameworks of social ecological theory and developmental criminology. A social ecological perspective broadens the understanding of factors associated with youth contact with justice systems and potential intervention opportunities. It is argued that the integration of developmental criminology and social ecological theory within a place based framework will guide understanding and enh ance the efficacy of early intervention strategies. This thesis highlight s the need to consider multiple interacting factors, the value of incorporating developmental data to augment police records and the importance of implementing practice wisdom in the formulation and delivery of developmental prevention strategies. An individual’s exposure to adverse childhood experiences is demonstrated as a critical element associated with the risk of future offending. Findings relating to early contact with police as potentially protective and not necessarily predictive of an ongoing offending trajectory provide new insight. It is argued that a place based approach that incorporat es practice partnerships is critical to delivering effective prevention efforts. This research project was supported through a universityearch project was supported through a university––service system research service system research collaboration within the Inner Gippsland region of Victoria. The study has generated ‘local collaboration within the Inner Gippsland region of Victoria. The study has generated ‘local solutions to local problems’ and bridged the practicesolutions to local problems’ and bridged the practice––research gap research gap by generating by generating conceptualconceptually sound, evidencely sound, evidence--based interventions based interventions that are that are responsive to the Inner responsive to the Inner Gippsland community.Gippsland community.
- Description: Doctor of Philosophy
- Authors: Lancefield, Kay
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The involvement of youth in justice systems generates high social and economic costs for individuals, their families and communities. Although Victorian crime statistics indicate a decline in youth offending there remains a subgroup who persist, resulting in adverse outcomes. Despite considerable scholarly attention on the factors that contribute to youth contact with justice systems, the application of this knowledge in some instances has failed to reduce such contact and deliver the desired outcomes. This thesis asserts that the factors relat ing to youth contact with justice systems are best understood within the theoretical frameworks of social ecological theory and developmental criminology. A social ecological perspective broadens the understanding of factors associated with youth contact with justice systems and potential intervention opportunities. It is argued that the integration of developmental criminology and social ecological theory within a place based framework will guide understanding and enh ance the efficacy of early intervention strategies. This thesis highlight s the need to consider multiple interacting factors, the value of incorporating developmental data to augment police records and the importance of implementing practice wisdom in the formulation and delivery of developmental prevention strategies. An individual’s exposure to adverse childhood experiences is demonstrated as a critical element associated with the risk of future offending. Findings relating to early contact with police as potentially protective and not necessarily predictive of an ongoing offending trajectory provide new insight. It is argued that a place based approach that incorporat es practice partnerships is critical to delivering effective prevention efforts. This research project was supported through a universityearch project was supported through a university––service system research service system research collaboration within the Inner Gippsland region of Victoria. The study has generated ‘local collaboration within the Inner Gippsland region of Victoria. The study has generated ‘local solutions to local problems’ and bridged the practicesolutions to local problems’ and bridged the practice––research gap research gap by generating by generating conceptualconceptually sound, evidencely sound, evidence--based interventions based interventions that are that are responsive to the Inner responsive to the Inner Gippsland community.Gippsland community.
- Description: Doctor of Philosophy
Ecologically sustainable forest management in Victoria : existing regulation and future directions
- Authors: Martin, Rhett
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The Sustainable Forests (Timber) Act 2004 (Vic) was designed as a framework for ecologically sustainable forest management (ESFM) of Victorian public forestry. It includes the principles of ecologically sustainable development (ESD). These principles are included in a range of natural resource management and conservation Acts around Australia. A separate regulatory framework applied to private forest management is also designed to support sustainable forest management. This study examines both the public and private sector forestry management in Victoria to appreciate the extent to which the existing framework for ESFM addresses the ESD principles. A critical realist research paradigm is adopted via regulatory theory, using four filtering mechanisms to assess the effectiveness of the current framework, including measuring and monitoring, compliance, ESD balance and governance standards. The thesis reports on two studies, that being public and private forestry. Within the two Victorian studies, an organisational perspective is also provided by way of analysis of the strategies and roles of VicForests (public) and Hancock Victorian Plantation Pty Ltd (HVP - the largest private forestry entity in Victoria.) Referring to regulatory theory and empirical evidence, an adapted regulatory mode using a precautionary risk management structure is proposed. This approach required application of sustainability criteria and indicators currently used to meet reporting obligations. The adapted regulation that resulted uses trigger points for an adaptive management response regulatory model. This model identifies the responsible parties for determining sustainability objectives and applying principles of ecologically sustainable development, data collection processes and review of data against criteria in order to activate the trigger and the resultant adaptive response. The end result is to evaluate data in order to determine when and how to activate a trigger for an adaptive response which is proportionate to the level of risk. The adapted model emphasises accountability and transparency, utilising bespoke sustainability criteria and indicators to inform each stage of the regulatory process. This model demonstrates the importance of using criteria and indicators in natural resource regulation, and that simply inserting sustainability principles and objectives into regulation is not sufficient to achieve worthwhile sustainability outcomes. This thesis concludes by evaluating this alternative model for implications to practice, policy and future research and its potential use in other resource sectors. Implications are drawn that this adapted framework could be a transferable template for other forestry jurisdictions and (with modifications) other natural resource sectors
- Description: Doctor of Philosophy
- Authors: Martin, Rhett
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: The Sustainable Forests (Timber) Act 2004 (Vic) was designed as a framework for ecologically sustainable forest management (ESFM) of Victorian public forestry. It includes the principles of ecologically sustainable development (ESD). These principles are included in a range of natural resource management and conservation Acts around Australia. A separate regulatory framework applied to private forest management is also designed to support sustainable forest management. This study examines both the public and private sector forestry management in Victoria to appreciate the extent to which the existing framework for ESFM addresses the ESD principles. A critical realist research paradigm is adopted via regulatory theory, using four filtering mechanisms to assess the effectiveness of the current framework, including measuring and monitoring, compliance, ESD balance and governance standards. The thesis reports on two studies, that being public and private forestry. Within the two Victorian studies, an organisational perspective is also provided by way of analysis of the strategies and roles of VicForests (public) and Hancock Victorian Plantation Pty Ltd (HVP - the largest private forestry entity in Victoria.) Referring to regulatory theory and empirical evidence, an adapted regulatory mode using a precautionary risk management structure is proposed. This approach required application of sustainability criteria and indicators currently used to meet reporting obligations. The adapted regulation that resulted uses trigger points for an adaptive management response regulatory model. This model identifies the responsible parties for determining sustainability objectives and applying principles of ecologically sustainable development, data collection processes and review of data against criteria in order to activate the trigger and the resultant adaptive response. The end result is to evaluate data in order to determine when and how to activate a trigger for an adaptive response which is proportionate to the level of risk. The adapted model emphasises accountability and transparency, utilising bespoke sustainability criteria and indicators to inform each stage of the regulatory process. This model demonstrates the importance of using criteria and indicators in natural resource regulation, and that simply inserting sustainability principles and objectives into regulation is not sufficient to achieve worthwhile sustainability outcomes. This thesis concludes by evaluating this alternative model for implications to practice, policy and future research and its potential use in other resource sectors. Implications are drawn that this adapted framework could be a transferable template for other forestry jurisdictions and (with modifications) other natural resource sectors
- Description: Doctor of Philosophy
Elastoplasticity of Victorian brown coal and its interaction with interseam clay
- Authors: Karami, Mojtaba
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Batter instability is one of the major geotechnical concerns in open-cut mining of recent decades. A key factor in undertaking any stability assessment of batters and determining their Factor of Safety (FoS) against instability is understanding the geotechnical properties of the material comprising the batters. These geotechnical properties usually include stiffness and strength under various loading conditions such as compression, extension and creep. This thesis presents a comprehensive study of the geotechnical properties of materials comprising the batters in the Yallourn open-cut mine in Victoria, Australia, located at one of the largest sources of brown coal in the world. The materials studied in this research are Victorian Brown Coal (VBC) and fine-grained interseam material (containing mainly silt and clay particles). The presented study is based on four key steps undertaken during the research project: 1. Field investigation This step included drilling boreholes at the mine floor and mine crest and recovering samples of VBC and interseam for laboratory testing. Sample trays were logged to provide lithology data required for model generation for numerical modelling undertaken by other PhD students. 2. Laboratory testing This step involved a wide range of laboratory tests on undisturbed samples of VBC and interseam material to investigate soil characteristics, stiffness and strength of tested materials. 3. Data analysis and parameter determination This step included analysing the laboratory test results, preparing stress-strain plots and determining material properties such as pre-consolidation pressure, stiffness and strength. 4. Numerical analysis and model calibration This step included selecting proper constitutive models and determining the models’ parameters based on laboratory tests. The capability of models was then examined by verifying numerical model simulation against laboratory test results. The laboratory tests indicated that VBC shows a hardening feature in compression, leading to brittle failure, while also showing a sharp post-peak softening behaviour. The tests also showed that the interseam material is heavily over-consolidated with a dilative hardening feature. The stiffness and shear strength of the interseam were found to be sensitive to the applied strain rate. The conducted creep tests (applying constant shear stress for a selected period) under triaxial undrained conditions resulted in developing pore water pressure leading to creep failure. Based on the laboratory test results and the obtained geotechnical features of the tested materials, Hardening Soil (HS) and Soft Soil Creep (SSC) models were chosen to describe the geotechnical behaviour of both VBC and interseam material. Both models were calibrated using test results and employed in simulated laboratory tests, including oedometer and triaxial Consolidated Undrained (CU) tests using the Finite Element Method (FEM). This study indicates that, although most of the models’ parameters were determined successfully based on laboratory test results, engineering judgement and back calculating were required to find the best fit for the numerical simulations. The numerical modelling of oedometer and triaxial tests showed that the nonlinear hardening behaviour of VBC and interseam material was captured by the HS model. The stress path in triaxial CU tests and the stress-strain curve in unloading-reloading were simulated well by the HS model. The strain-rate dependency and creep behaviour of interseam material were simulated well by the SSC model, indicating that this model can predict the long-term behaviour of interseam material.
- Description: Doctor of Philosophy
- Authors: Karami, Mojtaba
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Batter instability is one of the major geotechnical concerns in open-cut mining of recent decades. A key factor in undertaking any stability assessment of batters and determining their Factor of Safety (FoS) against instability is understanding the geotechnical properties of the material comprising the batters. These geotechnical properties usually include stiffness and strength under various loading conditions such as compression, extension and creep. This thesis presents a comprehensive study of the geotechnical properties of materials comprising the batters in the Yallourn open-cut mine in Victoria, Australia, located at one of the largest sources of brown coal in the world. The materials studied in this research are Victorian Brown Coal (VBC) and fine-grained interseam material (containing mainly silt and clay particles). The presented study is based on four key steps undertaken during the research project: 1. Field investigation This step included drilling boreholes at the mine floor and mine crest and recovering samples of VBC and interseam for laboratory testing. Sample trays were logged to provide lithology data required for model generation for numerical modelling undertaken by other PhD students. 2. Laboratory testing This step involved a wide range of laboratory tests on undisturbed samples of VBC and interseam material to investigate soil characteristics, stiffness and strength of tested materials. 3. Data analysis and parameter determination This step included analysing the laboratory test results, preparing stress-strain plots and determining material properties such as pre-consolidation pressure, stiffness and strength. 4. Numerical analysis and model calibration This step included selecting proper constitutive models and determining the models’ parameters based on laboratory tests. The capability of models was then examined by verifying numerical model simulation against laboratory test results. The laboratory tests indicated that VBC shows a hardening feature in compression, leading to brittle failure, while also showing a sharp post-peak softening behaviour. The tests also showed that the interseam material is heavily over-consolidated with a dilative hardening feature. The stiffness and shear strength of the interseam were found to be sensitive to the applied strain rate. The conducted creep tests (applying constant shear stress for a selected period) under triaxial undrained conditions resulted in developing pore water pressure leading to creep failure. Based on the laboratory test results and the obtained geotechnical features of the tested materials, Hardening Soil (HS) and Soft Soil Creep (SSC) models were chosen to describe the geotechnical behaviour of both VBC and interseam material. Both models were calibrated using test results and employed in simulated laboratory tests, including oedometer and triaxial Consolidated Undrained (CU) tests using the Finite Element Method (FEM). This study indicates that, although most of the models’ parameters were determined successfully based on laboratory test results, engineering judgement and back calculating were required to find the best fit for the numerical simulations. The numerical modelling of oedometer and triaxial tests showed that the nonlinear hardening behaviour of VBC and interseam material was captured by the HS model. The stress path in triaxial CU tests and the stress-strain curve in unloading-reloading were simulated well by the HS model. The strain-rate dependency and creep behaviour of interseam material were simulated well by the SSC model, indicating that this model can predict the long-term behaviour of interseam material.
- Description: Doctor of Philosophy
Engagement with voluntary family services : views of parents and practitioners
- Authors: Randall, Mary
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: This research aimed to understand engagement with voluntary family services, which has implications for service policy and practice. In regions of high social disadvantage, such as the Inner Gippsland region in the state of Victoria (Australia), engagement with voluntary family services is vital to reduce harm for children. However, barriers to engagement need to be understood from the perspectives of parents and practitioners. While the literature is replete with studies and records on engagement of parents and practitioners with statutory child protective services, there are few studies on engagement for families serviced by voluntary family services, which accept a range of referral sources. To address this gap, this study conducted ten qualitative semi-structured interviews with parents referred to Inner Gippsland family services and seven interviews with practitioners. These were analysed using interpretative phenomenological analysis (IPA). Interview data were supported by quantitative data drawn from voluntary family service system records on service use across the region for 2016–17 and 2017–18. Mixed methods were employed. This study found that these regional and rural practitioners and parents conceived of engagement as open communication, trust, rapport and understanding. Practitioners also discussed engagement occurring at different levels and involving parents’ willingness to change. However, these aspects were not referred to by parents. Practitioners explained that parents may show full or meaningful engagement and set goals to work towards, or they may engage at a superficial level where they consult but do not value change. This indicates that the notion of ‘engagement’ held by parents is dissonant with that of service providers who focus on the documentation of goals and achievements. Factors influencing engagement included parent perceptions, practitioner disposition, power relations, system design and implementation. Parents expected practitioners to clearly explain services that are tailored to meet needs. Some parents were reluctant to engage fully and trust practitioners due to potential harm and the possibility of removal of their children from their care. Parents wanted support without judgement and for practitioners to provide friendly advice and not be authoritarian. Practitioners balanced assessments of child wellbeing with responding to family needs and emphasised empowering clients and relating to them humanely. Many parents did not feel family services were voluntary as they are connected to and mandated to report serious concerns to Child Protection.1 Most parents were reluctant to ask for help and were negatively disposed towards government Child Protection. Parents who self-referred to family services expressed the most willingness to use a service, while those referred by police did not tend to use a service past initial phone calls. Practitioner-documented service hours in the home, an objective indicator of engagement, were highest for families where an early learning or early childhood intervention agency had referred. These findings were consistent with the interview data showing parental reluctance to engage where there was fear of Child Protection intervention. The practices of prioritising cases of complexity or crisis clashed with policy ideals of prevention and early intervention. More complex issues for families in the region increased the likelihood of service availability and use, yet many families did not complete activities negotiated in service plans or engage to make a plan with practitioners. This study demonstrated that for supportive relationships that promote child and family wellbeing to occur in a regional and rural area, family services need to be trusted. Only then, according to parents, will engagement eventuate.
- Description: Doctor of Philosophy
- Authors: Randall, Mary
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: This research aimed to understand engagement with voluntary family services, which has implications for service policy and practice. In regions of high social disadvantage, such as the Inner Gippsland region in the state of Victoria (Australia), engagement with voluntary family services is vital to reduce harm for children. However, barriers to engagement need to be understood from the perspectives of parents and practitioners. While the literature is replete with studies and records on engagement of parents and practitioners with statutory child protective services, there are few studies on engagement for families serviced by voluntary family services, which accept a range of referral sources. To address this gap, this study conducted ten qualitative semi-structured interviews with parents referred to Inner Gippsland family services and seven interviews with practitioners. These were analysed using interpretative phenomenological analysis (IPA). Interview data were supported by quantitative data drawn from voluntary family service system records on service use across the region for 2016–17 and 2017–18. Mixed methods were employed. This study found that these regional and rural practitioners and parents conceived of engagement as open communication, trust, rapport and understanding. Practitioners also discussed engagement occurring at different levels and involving parents’ willingness to change. However, these aspects were not referred to by parents. Practitioners explained that parents may show full or meaningful engagement and set goals to work towards, or they may engage at a superficial level where they consult but do not value change. This indicates that the notion of ‘engagement’ held by parents is dissonant with that of service providers who focus on the documentation of goals and achievements. Factors influencing engagement included parent perceptions, practitioner disposition, power relations, system design and implementation. Parents expected practitioners to clearly explain services that are tailored to meet needs. Some parents were reluctant to engage fully and trust practitioners due to potential harm and the possibility of removal of their children from their care. Parents wanted support without judgement and for practitioners to provide friendly advice and not be authoritarian. Practitioners balanced assessments of child wellbeing with responding to family needs and emphasised empowering clients and relating to them humanely. Many parents did not feel family services were voluntary as they are connected to and mandated to report serious concerns to Child Protection.1 Most parents were reluctant to ask for help and were negatively disposed towards government Child Protection. Parents who self-referred to family services expressed the most willingness to use a service, while those referred by police did not tend to use a service past initial phone calls. Practitioner-documented service hours in the home, an objective indicator of engagement, were highest for families where an early learning or early childhood intervention agency had referred. These findings were consistent with the interview data showing parental reluctance to engage where there was fear of Child Protection intervention. The practices of prioritising cases of complexity or crisis clashed with policy ideals of prevention and early intervention. More complex issues for families in the region increased the likelihood of service availability and use, yet many families did not complete activities negotiated in service plans or engage to make a plan with practitioners. This study demonstrated that for supportive relationships that promote child and family wellbeing to occur in a regional and rural area, family services need to be trusted. Only then, according to parents, will engagement eventuate.
- Description: Doctor of Philosophy
Enhancing deep transfer learning for image classification
- Authors: Shermin, Tasfia
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Though deep learning models require a large amount of labelled training data for yielding high performance, they are applied to accomplish many computer vision tasks such as image classification. Current models also do not perform well across different domain settings such as illumination, camera angle and real-to-synthetic. Thus the models are more likely to misclassify unknown classes as known classes. These issues challenge the supervised learning paradigm of the models and encourage the study of transfer learning approaches. Transfer learning allows us to utilise the knowledge acquired from related domains to improve performance on a target domain. Existing transfer learning approaches lack proper high-level source domain feature analyses and are prone to negative transfers for not exploring proper discriminative information across domains. Current approaches also lack at discovering necessary visual-semantic linkage and has a bias towards the source domain. In this thesis, to address these issues and improve image classification performance, we make several contributions to three different deep transfer learning scenarios, i.e., the target domain has i) labelled data; no labelled data; and no visual data. Firstly, for improving inductive transfer learning for the first scenario, we analyse the importance of high-level deep features and propose utilising them in sequential transfer learning approaches and investigating the suitable conditions for optimal performance. Secondly, to improve image classification across different domains in an open set setting by reducing negative transfers (second scenario), we propose two novel architectures. The first model has an adaptive weighting module based on underlying domain distinctive information, and the second model has an information-theoretic weighting module to reduce negative transfers. Thirdly, to learn visual classifiers when no visual data is available (third scenario) and reduce source domain bias, we propose two novel models. One model has a new two-step dense attention mechanism to discover semantic attribute-guided local visual features and mutual learning loss. The other model utilises bidirectional mapping and adversarial supervision to learn the joint distribution of source-target domains simultaneously. We propose a new pointwise mutual information dependant loss in the first model and a distance-based loss in the second one for handling source domain bias. We perform extensive evaluations on benchmark datasets and demonstrate the proposed models outperform contemporary works.
- Description: Doctor of Philosophy
- Authors: Shermin, Tasfia
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Though deep learning models require a large amount of labelled training data for yielding high performance, they are applied to accomplish many computer vision tasks such as image classification. Current models also do not perform well across different domain settings such as illumination, camera angle and real-to-synthetic. Thus the models are more likely to misclassify unknown classes as known classes. These issues challenge the supervised learning paradigm of the models and encourage the study of transfer learning approaches. Transfer learning allows us to utilise the knowledge acquired from related domains to improve performance on a target domain. Existing transfer learning approaches lack proper high-level source domain feature analyses and are prone to negative transfers for not exploring proper discriminative information across domains. Current approaches also lack at discovering necessary visual-semantic linkage and has a bias towards the source domain. In this thesis, to address these issues and improve image classification performance, we make several contributions to three different deep transfer learning scenarios, i.e., the target domain has i) labelled data; no labelled data; and no visual data. Firstly, for improving inductive transfer learning for the first scenario, we analyse the importance of high-level deep features and propose utilising them in sequential transfer learning approaches and investigating the suitable conditions for optimal performance. Secondly, to improve image classification across different domains in an open set setting by reducing negative transfers (second scenario), we propose two novel architectures. The first model has an adaptive weighting module based on underlying domain distinctive information, and the second model has an information-theoretic weighting module to reduce negative transfers. Thirdly, to learn visual classifiers when no visual data is available (third scenario) and reduce source domain bias, we propose two novel models. One model has a new two-step dense attention mechanism to discover semantic attribute-guided local visual features and mutual learning loss. The other model utilises bidirectional mapping and adversarial supervision to learn the joint distribution of source-target domains simultaneously. We propose a new pointwise mutual information dependant loss in the first model and a distance-based loss in the second one for handling source domain bias. We perform extensive evaluations on benchmark datasets and demonstrate the proposed models outperform contemporary works.
- Description: Doctor of Philosophy
Examining factors that influence the relationship between personality and stress
- Authors: Duggan, Leanne
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Individual differences in the stress response have been linked with numerous factors, including personality traits and mindfulness. Selye (1950) was among the first to detail the physiological stress response that takes place during a stressful event, or after exposure to a stressor. These responses include heart rate changes and the secretion of cortisol into the blood stream, which are key physiological indicators that a stress response is taking place. Lazarus and Folkman (1984) examined appraisal of stressful events, determining that this is crucial to the stress experience. An extension of Lazarus and Folkman’s cognitive appraisal theory was offered by Vollrath (2001), suggesting an individual’s personality accentuates our stress response, therefore, offering an explanation for the individual differences evident in stress responses. The relationship between personality and stress is not straight forward, and other factors, such as affect and mindfulness, may influence this relationship. Thus, this dissertation is divided into three studies. Study 1 examined the moderating and mediating factors of affect on the relationship between personality traits and perceived stress. A total of 290 adults (71% female; Mage = 35.0 years, SD = 12.92) completed an online questionnaire package, comprising of the Perceived Stress Scale, Big Five Inventory, Positive and Negative Affect Schedule, and a number of demographic questions. A hierarchical regression showed that 56% of the variance in perceived stress was explained by personality and affect, and when all personality traits were viewed concurrently and with affect, neuroticism was the only one to significantly explain variance in perceived stress. No moderation effects were found in Study 1 however, positive affect partially mediated the relationship between neuroticism and perceived stress. Study 2 aimed to further the findings of Study 1 by investigating whether trait mindfulness impacted the relationship between personality and stress. A total of 266 adults (70% female; Mage = 34.0 years, SD = 12.68) completed an online questionnaire package, consisting of the Perceived Stress Scale, Big Five Inventory, and Carolina Empirically Derived Mindfulness Scale. A hierarchical regression showed that 58% of the variance in perceived stress was explained by personality and trait mindfulness. When all personality traits and trait mindfulness were viewed together, neuroticism and agreeableness were the only personality traits to significantly explain variance in perceived stress. The sub-scale trait mindfulness attention significantly moderated the relationship between agreeableness and perceived stress, while a partial mediation was found between neuroticism and the sub-scale trait mindfulness acceptance. Study 3 investigated the effectiveness of a brief state-based mindfulness intervention on physiological (cortisol and heart rate) and psychological stress responses, in a participant matched design. A total of 20 participants (60% female; Mage = 34.60 years, SD = 14.68) were recruited from Studies 1 and/or 2 and matched based on gender, dominant personality trait (found in Study 1 and 2), and perceived stress. One participant in each matched pair was then randomly allocated to the mindfulness experimental, or control, group. The mindfulness experimental group completed a 10-minute breathing exercise, prior to completing the Trier Social Stress Test, a verbal presentation and arithmetic task, designed to induce stress. The control group did not complete any activity prior to the stress test. Comparison of the groups indicated that no significant differences in perceived stress were evident pre-post- intervention. Changes in heart rate were noted for all participants during the intervention, though no difference was evident between groups. The results of Study 3 indicate a mindfulness breathing exercise makes little difference to physiological stress responses during a stress task. The combined findings of this dissertation indicate that personality traits can influence the likelihood of an individual experiencing stress. Mindfulness and affect also impact on the relationship between personality and stress and offer some insight into the individual experience of stress responses.
- Description: Doctor of Philosophy
- Authors: Duggan, Leanne
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Individual differences in the stress response have been linked with numerous factors, including personality traits and mindfulness. Selye (1950) was among the first to detail the physiological stress response that takes place during a stressful event, or after exposure to a stressor. These responses include heart rate changes and the secretion of cortisol into the blood stream, which are key physiological indicators that a stress response is taking place. Lazarus and Folkman (1984) examined appraisal of stressful events, determining that this is crucial to the stress experience. An extension of Lazarus and Folkman’s cognitive appraisal theory was offered by Vollrath (2001), suggesting an individual’s personality accentuates our stress response, therefore, offering an explanation for the individual differences evident in stress responses. The relationship between personality and stress is not straight forward, and other factors, such as affect and mindfulness, may influence this relationship. Thus, this dissertation is divided into three studies. Study 1 examined the moderating and mediating factors of affect on the relationship between personality traits and perceived stress. A total of 290 adults (71% female; Mage = 35.0 years, SD = 12.92) completed an online questionnaire package, comprising of the Perceived Stress Scale, Big Five Inventory, Positive and Negative Affect Schedule, and a number of demographic questions. A hierarchical regression showed that 56% of the variance in perceived stress was explained by personality and affect, and when all personality traits were viewed concurrently and with affect, neuroticism was the only one to significantly explain variance in perceived stress. No moderation effects were found in Study 1 however, positive affect partially mediated the relationship between neuroticism and perceived stress. Study 2 aimed to further the findings of Study 1 by investigating whether trait mindfulness impacted the relationship between personality and stress. A total of 266 adults (70% female; Mage = 34.0 years, SD = 12.68) completed an online questionnaire package, consisting of the Perceived Stress Scale, Big Five Inventory, and Carolina Empirically Derived Mindfulness Scale. A hierarchical regression showed that 58% of the variance in perceived stress was explained by personality and trait mindfulness. When all personality traits and trait mindfulness were viewed together, neuroticism and agreeableness were the only personality traits to significantly explain variance in perceived stress. The sub-scale trait mindfulness attention significantly moderated the relationship between agreeableness and perceived stress, while a partial mediation was found between neuroticism and the sub-scale trait mindfulness acceptance. Study 3 investigated the effectiveness of a brief state-based mindfulness intervention on physiological (cortisol and heart rate) and psychological stress responses, in a participant matched design. A total of 20 participants (60% female; Mage = 34.60 years, SD = 14.68) were recruited from Studies 1 and/or 2 and matched based on gender, dominant personality trait (found in Study 1 and 2), and perceived stress. One participant in each matched pair was then randomly allocated to the mindfulness experimental, or control, group. The mindfulness experimental group completed a 10-minute breathing exercise, prior to completing the Trier Social Stress Test, a verbal presentation and arithmetic task, designed to induce stress. The control group did not complete any activity prior to the stress test. Comparison of the groups indicated that no significant differences in perceived stress were evident pre-post- intervention. Changes in heart rate were noted for all participants during the intervention, though no difference was evident between groups. The results of Study 3 indicate a mindfulness breathing exercise makes little difference to physiological stress responses during a stress task. The combined findings of this dissertation indicate that personality traits can influence the likelihood of an individual experiencing stress. Mindfulness and affect also impact on the relationship between personality and stress and offer some insight into the individual experience of stress responses.
- Description: Doctor of Philosophy
Exploring interprofessional clinical placements to understand perceptions and outcomes for pre-registration healthcare students
- Authors: Hood, Kerry
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background There is an ongoing need for preregistration healthcare students to acquire skills that equip them to collaborate with others for patient-centred care and outcomes. Traditional models of university learning and clinical placement seldom offer students the opportunities to experience interprofessional learning or to ‘test the waters’ of collaborative practice. Aims A range of interprofessional learning opportunities were offered to preregistration healthcare students while on clinical placement in a large metropolitan health service. This research evaluated interprofessional learning opportunities for preregistration healthcare students as preparation for collaborative practice. It also explored the perceived value for student learning of these activities and examined the challenges and opportunities accompanying the design and implementation of the student-led beds model. Methods A mixed methods approach was undertaken. In particular, there was a focus on the experiences of students in an immersive two-week interprofessional placement in which interprofessional student teams worked together to lead the care of inpatients in a variety of clinical settings. This experience enabled students to experience authentic collaborative practice in a real clinical setting. The Theory of Planned Behaviour was used to retrospectively evaluate the findings presented in the published papers. Outcomes This research reflects a journey of student experience of clinical interprofessional learning (IPL), from understanding attitudes to IPL to perceptions of clinical workshops and culminating in the experience of an immersive clinical placement. Outcomes included positive learning experiences and a sense of clarity of professional and interprofessional identity. The model of placement was informed by the international literature, most notably the ‘student-led bed’ model pioneered at Karolinska Institute in Sweden. Despite solid evidence of the usefulness and efficacy of this model, it is yet to be embedded in clinical environments across the world. This research demonstrated that the model can be successfully implemented in a metropolitan health service and may contribute to real behavioural change of our future health professionals
- Description: Doctor of Philosophy
- Authors: Hood, Kerry
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background There is an ongoing need for preregistration healthcare students to acquire skills that equip them to collaborate with others for patient-centred care and outcomes. Traditional models of university learning and clinical placement seldom offer students the opportunities to experience interprofessional learning or to ‘test the waters’ of collaborative practice. Aims A range of interprofessional learning opportunities were offered to preregistration healthcare students while on clinical placement in a large metropolitan health service. This research evaluated interprofessional learning opportunities for preregistration healthcare students as preparation for collaborative practice. It also explored the perceived value for student learning of these activities and examined the challenges and opportunities accompanying the design and implementation of the student-led beds model. Methods A mixed methods approach was undertaken. In particular, there was a focus on the experiences of students in an immersive two-week interprofessional placement in which interprofessional student teams worked together to lead the care of inpatients in a variety of clinical settings. This experience enabled students to experience authentic collaborative practice in a real clinical setting. The Theory of Planned Behaviour was used to retrospectively evaluate the findings presented in the published papers. Outcomes This research reflects a journey of student experience of clinical interprofessional learning (IPL), from understanding attitudes to IPL to perceptions of clinical workshops and culminating in the experience of an immersive clinical placement. Outcomes included positive learning experiences and a sense of clarity of professional and interprofessional identity. The model of placement was informed by the international literature, most notably the ‘student-led bed’ model pioneered at Karolinska Institute in Sweden. Despite solid evidence of the usefulness and efficacy of this model, it is yet to be embedded in clinical environments across the world. This research demonstrated that the model can be successfully implemented in a metropolitan health service and may contribute to real behavioural change of our future health professionals
- Description: Doctor of Philosophy
Exploring the development of thinking in senior secondary mathematics : a focus on probability
- Authors: Ernst, Heather
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Higher order thinking skills have been identified as desirable although elusive outcomes of many educational curricula. Through a qualitative case study, the alignment between the three levels of the curriculum: intended, implemented, and attained, was examined to determine the tensions and possibilities in the development of mathematical and thinking skills in senior secondary students in Gippsland, a large regional area of Victoria, Australia. Probability was the mathematical content area of focus. Data from document analysis of the intended curriculum, textbooks as the implemented curriculum, and assessments as the attained curriculum, was combined with qualitative data from semi-structured interviews with twenty students and fourteen senior secondary mathematics teachers. These diverse data sources scaffolded each other to identify tensions and possibilities influencing development of student thinking in senior secondary mathematics. This research demonstrated that the flow of content via the intended-implemented-attained curriculum was not adequate to describe all the influences on student learning. The lens of Activity Theory (Engeström, 2001) came closer to capturing the related complexities whereby the textbooks, calculators, bound reference books and assessments, combined with the balance of agency demonstrated by the teachers and students, were found to both support and cause tensions within the activity system. Probability was found to be a valuable topic to study in relation to the development of thinking skills due to its relevance in decision making, how it linked many areas of mathematics and the uniqueness of the classic, experimental, and subjective views of probability. This study is significant in the contribution it makes to understanding the tensions and possibilities associated with the development of mathematical thinking relating to probability through the lens of Activity Theory. While the intended curriculum encouraged a range of thinking skills, this intended curriculum could be implemented in a way that promotes memorisation rather than the intended higher order thinking. This study concludes with recommendations for the curriculum designers, textbook publishers, teachers, and students which may support the development of mathematical and thinking skills.
- Description: Doctor of Philosophy
- Authors: Ernst, Heather
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Higher order thinking skills have been identified as desirable although elusive outcomes of many educational curricula. Through a qualitative case study, the alignment between the three levels of the curriculum: intended, implemented, and attained, was examined to determine the tensions and possibilities in the development of mathematical and thinking skills in senior secondary students in Gippsland, a large regional area of Victoria, Australia. Probability was the mathematical content area of focus. Data from document analysis of the intended curriculum, textbooks as the implemented curriculum, and assessments as the attained curriculum, was combined with qualitative data from semi-structured interviews with twenty students and fourteen senior secondary mathematics teachers. These diverse data sources scaffolded each other to identify tensions and possibilities influencing development of student thinking in senior secondary mathematics. This research demonstrated that the flow of content via the intended-implemented-attained curriculum was not adequate to describe all the influences on student learning. The lens of Activity Theory (Engeström, 2001) came closer to capturing the related complexities whereby the textbooks, calculators, bound reference books and assessments, combined with the balance of agency demonstrated by the teachers and students, were found to both support and cause tensions within the activity system. Probability was found to be a valuable topic to study in relation to the development of thinking skills due to its relevance in decision making, how it linked many areas of mathematics and the uniqueness of the classic, experimental, and subjective views of probability. This study is significant in the contribution it makes to understanding the tensions and possibilities associated with the development of mathematical thinking relating to probability through the lens of Activity Theory. While the intended curriculum encouraged a range of thinking skills, this intended curriculum could be implemented in a way that promotes memorisation rather than the intended higher order thinking. This study concludes with recommendations for the curriculum designers, textbook publishers, teachers, and students which may support the development of mathematical and thinking skills.
- Description: Doctor of Philosophy
Genetic and epigenetic changes associated with polygenic left ventricular hypertrophy
- Authors: Prestes, Priscilla
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Cardiac hypertrophy (CH) is the thickening of heart muscles reducing functionality and increasing risk of cardiac disease. Commonly, pathological CH is presented as left ventricular hypertrophy (LVH) and genetic factors are known to be involved but their contribution is still poorly understood. I used the hypertrophic heart rat (HHR), a unique normotensive polygenic model of LVH, and its control strain, the normal heart rat (NHR) to investigate genetic and epigenetic contributions to LVH independent of high blood pressure. To address this study, I used a systematic approach. Firstly, I sequenced the whole genome of HHR and NHR to identify genes related to LVH, focusing on quantitative trait locus Cm22. I found the gene for tripartite motif-containing 55 (Trim55) was significantly downregulated and also presented decreased protein expression with the presence of one exonic missense mutation that altered the protein structure. Interestingly, Trim55 mRNA expression was reduced in idiopathic dilated cardiomyopathic hearts. Secondly, I selected 42 genes previously described in monogenic forms of human cardiomyopathies and studied DNA variants, mRNA and micro RNA (miRNA) expression to determine their involvement in this polygenic model of LVH at five ages. This comprehensive approach identified the differential expression of 29 genes in at least one age group and two miRNAs in validated miRNA-mRNA interactions. These two miRNAs have binding sites for five of the genes studied. Lastly, I found circular RNA (circRNA) Hrcr was upregulated in the hypertrophic heart. I then silenced Hrcr expression in human primary cardiomyocytes to investigate its miRNA downstream targets and elucidate possible regulatory mechanisms. I described four miRNAs (miR-1-3p, miR-330, miR-27a-5p, miR-299-5p) as novel targets for HRCR and predicted 359 mRNA targets in the circRNA-miRNA-mRNA regulatory axis. In silico analysis identified 206 enriched gene ontology based on the predicted mRNA target list, including cardiomyocyte differentiation and ventricular cardiac muscle cell differentiation. The findings in this thesis suggest that 1) Trim55 is a novel functional candidate gene for polygenic LVH; 2) genes implicated in monogenic forms of cardiomyopathy may be involved in this condition and 3) circRNA expression is associated with changes in hypertrophic hearts and deserve further attention.
- Description: Doctor of Philosophy
- Authors: Prestes, Priscilla
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Cardiac hypertrophy (CH) is the thickening of heart muscles reducing functionality and increasing risk of cardiac disease. Commonly, pathological CH is presented as left ventricular hypertrophy (LVH) and genetic factors are known to be involved but their contribution is still poorly understood. I used the hypertrophic heart rat (HHR), a unique normotensive polygenic model of LVH, and its control strain, the normal heart rat (NHR) to investigate genetic and epigenetic contributions to LVH independent of high blood pressure. To address this study, I used a systematic approach. Firstly, I sequenced the whole genome of HHR and NHR to identify genes related to LVH, focusing on quantitative trait locus Cm22. I found the gene for tripartite motif-containing 55 (Trim55) was significantly downregulated and also presented decreased protein expression with the presence of one exonic missense mutation that altered the protein structure. Interestingly, Trim55 mRNA expression was reduced in idiopathic dilated cardiomyopathic hearts. Secondly, I selected 42 genes previously described in monogenic forms of human cardiomyopathies and studied DNA variants, mRNA and micro RNA (miRNA) expression to determine their involvement in this polygenic model of LVH at five ages. This comprehensive approach identified the differential expression of 29 genes in at least one age group and two miRNAs in validated miRNA-mRNA interactions. These two miRNAs have binding sites for five of the genes studied. Lastly, I found circular RNA (circRNA) Hrcr was upregulated in the hypertrophic heart. I then silenced Hrcr expression in human primary cardiomyocytes to investigate its miRNA downstream targets and elucidate possible regulatory mechanisms. I described four miRNAs (miR-1-3p, miR-330, miR-27a-5p, miR-299-5p) as novel targets for HRCR and predicted 359 mRNA targets in the circRNA-miRNA-mRNA regulatory axis. In silico analysis identified 206 enriched gene ontology based on the predicted mRNA target list, including cardiomyocyte differentiation and ventricular cardiac muscle cell differentiation. The findings in this thesis suggest that 1) Trim55 is a novel functional candidate gene for polygenic LVH; 2) genes implicated in monogenic forms of cardiomyopathy may be involved in this condition and 3) circRNA expression is associated with changes in hypertrophic hearts and deserve further attention.
- Description: Doctor of Philosophy
Investigation of unconventional T cells in patients with haematological malignancies
- Authors: Develyn, Tamekha
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Haematological malignancies involve the uncontrolled division of white blood cells, which can lead to an accumulation of these cells in lymphoid organs and cause the disruption of normal immune function. Multiple Myeloma (MM) and Myelodysplastic syndromes (MDS) are the most common haematological disorders among the elderly (Elidrissi Errahhali et al, 2016), but despite recent advances in treatment options, most individuals with MM or MDS eventually relapse and succumb to the disease (Rjkumar 2020 and Schurch 2018 and Kumar et al, 2012). The association of immune defects with MM and MDS may be a factor in disease progression, therefore it is important to develop a comprehensive understanding of how the immune system changes throughout the progression of these diseases, so that more effective treatment options can be developed. This thesis presents a detailed analysis of the frequency, phenotype and function of conventional T cells, unconventional T cells and antigen presenting cells (APC) throughout the progression of MM and MDS. This analysis has identified a range of immune abnormalities within these patient groups, including novel findings that provide new insights into disease progression and potential new targets for immune therapies. Some of the abnormalities we identified in patients with MM and MDS include; a reduction in the frequency of unconventional T cell (Natural Killer T (NKT) cells and Mucosal Associated Invariant T (MAIT) cells), as well as reduced frequencies of various APC populations. We also reported an increased expression of chronic activation and exhaustion markers on CD8+ T cells and MAIT cells, despite their retention of functional capacity. Importantly, the abnormalities we observed in patients with MM were consistent from the pre-malignant disease stage to active disease, which has not been shown previously suggesting that many of these defects are present from very early in disease development. We also identified key differences in the frequency and phenotype of conventional T cells, unconventional T cells and APC between patients with MM and those with MDS. Together highlighting the many different immune changes that are occurring within these patients groups and the importance of analysing haematological malignancies as individual diseases rather than as a collective. One of the most significant findings in this thesis was the alteration in frequency and phenotype of MAIT cells within the blood of patients with MM and MDS. MAIT cells may have important roles in anti-tumour immunity, so we explored the potential causes of these changes, including soluble factors and cell-to-cell interactions between MAIT cells and APC. Interestingly, we found MM patient plasma contained increased levels of IL-18, which is a cytokine known to influence MAIT cell function. This led us to establishing a long term in vitro culture of sorted MAIT cells supplemented with IL-18, finding that culturing MAIT cells with IL-18 lead to rapid expansion of MAIT cells without otherwise alternating their phenotype or function. We next established a novel mixed-donor MAIT cell co-culture system to examine the interactions between sorted healthy MAIT cells and APC from patients. This system uniquely allowed us to investigate whether abnormal patient APC were capable of stimulating MAIT cells and whether MAIT cell responses were altered as a result of this interaction. Whilst this was conducted as a pilot study to look for potentially important interactions rather than significance, we did conclude that culturing healthy donor MAIT cells with APC from monoclonal gammopathy of undetermined significance (MGUS) and MM patients did not lead to alterations in phenotype. The development and application of these long term MAIT cell cultures shed new light on how MAIT cell defects emerge in MM and MDS, and has also provided valuable insights into optimal MAIT cell growth conditions, which could be applied in the future to analyse other complex disease settings and for the use in therapeutic approaches. Our research was the first comprehensive study to characterise immune system alterations at both the individual cell population level and to examine their functional interactions throughout all stages of MM and in MDS. We discovered a range of novel findings which have greatly improved our understanding of the role that these various immune cells populations might play in MM and MDS, and identified new areas of study that could lead to improved disease management.
- Description: Doctor of Philosophy
- Authors: Develyn, Tamekha
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Haematological malignancies involve the uncontrolled division of white blood cells, which can lead to an accumulation of these cells in lymphoid organs and cause the disruption of normal immune function. Multiple Myeloma (MM) and Myelodysplastic syndromes (MDS) are the most common haematological disorders among the elderly (Elidrissi Errahhali et al, 2016), but despite recent advances in treatment options, most individuals with MM or MDS eventually relapse and succumb to the disease (Rjkumar 2020 and Schurch 2018 and Kumar et al, 2012). The association of immune defects with MM and MDS may be a factor in disease progression, therefore it is important to develop a comprehensive understanding of how the immune system changes throughout the progression of these diseases, so that more effective treatment options can be developed. This thesis presents a detailed analysis of the frequency, phenotype and function of conventional T cells, unconventional T cells and antigen presenting cells (APC) throughout the progression of MM and MDS. This analysis has identified a range of immune abnormalities within these patient groups, including novel findings that provide new insights into disease progression and potential new targets for immune therapies. Some of the abnormalities we identified in patients with MM and MDS include; a reduction in the frequency of unconventional T cell (Natural Killer T (NKT) cells and Mucosal Associated Invariant T (MAIT) cells), as well as reduced frequencies of various APC populations. We also reported an increased expression of chronic activation and exhaustion markers on CD8+ T cells and MAIT cells, despite their retention of functional capacity. Importantly, the abnormalities we observed in patients with MM were consistent from the pre-malignant disease stage to active disease, which has not been shown previously suggesting that many of these defects are present from very early in disease development. We also identified key differences in the frequency and phenotype of conventional T cells, unconventional T cells and APC between patients with MM and those with MDS. Together highlighting the many different immune changes that are occurring within these patients groups and the importance of analysing haematological malignancies as individual diseases rather than as a collective. One of the most significant findings in this thesis was the alteration in frequency and phenotype of MAIT cells within the blood of patients with MM and MDS. MAIT cells may have important roles in anti-tumour immunity, so we explored the potential causes of these changes, including soluble factors and cell-to-cell interactions between MAIT cells and APC. Interestingly, we found MM patient plasma contained increased levels of IL-18, which is a cytokine known to influence MAIT cell function. This led us to establishing a long term in vitro culture of sorted MAIT cells supplemented with IL-18, finding that culturing MAIT cells with IL-18 lead to rapid expansion of MAIT cells without otherwise alternating their phenotype or function. We next established a novel mixed-donor MAIT cell co-culture system to examine the interactions between sorted healthy MAIT cells and APC from patients. This system uniquely allowed us to investigate whether abnormal patient APC were capable of stimulating MAIT cells and whether MAIT cell responses were altered as a result of this interaction. Whilst this was conducted as a pilot study to look for potentially important interactions rather than significance, we did conclude that culturing healthy donor MAIT cells with APC from monoclonal gammopathy of undetermined significance (MGUS) and MM patients did not lead to alterations in phenotype. The development and application of these long term MAIT cell cultures shed new light on how MAIT cell defects emerge in MM and MDS, and has also provided valuable insights into optimal MAIT cell growth conditions, which could be applied in the future to analyse other complex disease settings and for the use in therapeutic approaches. Our research was the first comprehensive study to characterise immune system alterations at both the individual cell population level and to examine their functional interactions throughout all stages of MM and in MDS. We discovered a range of novel findings which have greatly improved our understanding of the role that these various immune cells populations might play in MM and MDS, and identified new areas of study that could lead to improved disease management.
- Description: Doctor of Philosophy