Quantitative and qualitative assessment of the regenerative potential of osteoblasts versus bone marrow derived mesenchymal stem cells in the reconstruction of critical sized segmental tibial bone defects in a large animal model

This thesis is about the use of different cells for bone tissue engineering. The cells were used in combination with a novel biomaterial in a large tibial bone defects in a sheep model. Furthermore this study developed a novel cell delivery procedure for bone tissue engineering. This novel procedure of cell delivery could overcome the current problems of cell-based tissue engineering and serve as a baseline for the translation of novel concepts into clinical application.

A critical analysis of crisis escalation models : understanding stages and severity in infrastructure disturbance

A range of authors from the risk management, crisis management, and crisis communications literature have proposed different models as a means of understanding components of crisis. A generic component of these sources has focused on preparedness practices before disturbance events and response practices during events. This paper provides a critical analysis of three key explanatory models of how crises escalate highlighting the strengths and limitations of each approach. The paper introduces an optimised conceptual model utilising components from the previous work under the four phases of pre-event, response, recovery, and post-event. Within these four phases, a ten step process is introduced that can enhance understanding of the progression of distinct stages of disturbance for different types of events. This crisis evolution framework is examined as a means to provide clarity and applicability to a range of infrastructure failure contexts and provide a path for further empirical investigation in this area.

A critical success factors model for ERP implementation

An effective IT infrastructure can support a business vision and strategy; a poor, decentralized one can break a company. More and more companies are turning to off-the-shelf ERP (enterprise resource planning) solutions for IT planning and legacy systems management. The authors have developed a framework to help managers successfully plan and implement an ERP project

Critical reflection on the SIA’s professional project and the body of knowledge

Over the last few years the Safety Institute of Australia (SIA) has developed and implemented a number of strategies to gain professional status for the ‘generalist occupational health and safety professional’. Two of the most significant developments have been the publication of the ‘Core Body of Knowledge for the Generalist OHS Professional.’ and the accreditation of university OHS courses. Despite a considerable amount of work aimed at gaining professional status there has not been any public debate or reflection about how the professionalisation project may impact on OHS and how the project is being conducted. Professionalisation has been vigorously promoted as a sign of maturity for the SIA and which will provide unmitigated benefits for workplace health and safety. The aim of this paper is to critically reflect on the processes of professionalisation (the professional project) and discuss some of the ways in which this project may shape the field of occupational health and safety. The implications for the role of universities will also be discussed.

Collaborative learning and critical thinking in technology-enhanced environments : an instructional design framework

The nature and characteristics of how learners learn today are changing. As technology use in learning and teaching continues to grow, its integration to facilitate deep learning and critical thinking becomes a primary consideration. The implications for learner use, implementation strategies, design of integration frameworks and evaluation of their effectiveness in learning environments cannot be overlooked. This study specifically looked at the impact that technology-enhanced learning environments have on different learners’ critical thinking in relation to eductive ability, technological self-efficacy, and approaches to learning and motivation in collaborative groups. These were explored within an instructional design framework called CoLeCTTE (collaborative learning and critical thinking in technology-enhanced environments) which was proposed, revised and used across three cases. The field of investigation was restricted to three key questions: 1) Do learner skill bases (learning approach and eductive ability) influence critical thinking within the proposed CoLeCTTE framework? If so, how?; 2) Do learning technologies influence the facilitation of deep learning and critical thinking within the proposed CoLeCTTE framework? If so, how?; and 3) How might learning be designed to facilitate the acquisition of deep learning and critical thinking within a technology-enabled collaborative environment? The rationale, assumptions and method of research for using a mixed method and naturalistic case study approach are discussed; and three cases are explored and analysed. The study was conducted at the tertiary level (undergraduate and postgraduate) where participants were engaged in critical technical discourse within their own disciplines. Group behaviour was observed and coded, attributes or skill bases were measured, and participants interviewed to acquire deeper insights into their experiences. A progressive case study approach was used, allowing case investigation to be implemented in a "ladder-like" manner. Cases 1 and 2 used the proposed CoLeCTTE framework with more in-depth analysis conducted for Case 2 resulting in a revision of the CoLeCTTE framework. Case 3 used the revised CoLeCTTE framework and in-depth analysis was conducted. The findings led to the final version of the framework. In Cases 1, 2 and 3, content analysis of group work was conducted to determine critical thinking performance. Thus, the researcher used three small groups where learner skill bases of eductive ability, technological self-efficacy, and approaches to learning and motivation were measured. Cases 2 and 3 participants were interviewed and observations provided more in-depth analysis. The main outcome of this study is analysis of the nature of critical thinking within collaborative groups and technology-enhanced environments positioned in a theoretical instructional design framework called CoLeCTTE. The findings of the study revealed the importance of the Achieving Motive dimension of a student’s learning approach and how direct intervention and strategies can positively influence critical thinking performance. The findings also identified factors that can adversely affect critical thinking performance and include poor learning skills, frustration, stress and poor self-confidence, prioritisations over learning; and inadequate appropriation of group role and tasks. These findings are set out as instructional design guidelines for the judicious integration of learning technologies into learning and teaching practice for higher education that will support deep learning and critical thinking in collaborative groups. These guidelines are presented in two key areas: technology and tools; and activity design, monitoring, control and feedback.

Susceptibility of the critical structural components of railway bridges to the changes in train speed

Modern trains with different axle configurations, speeds and loads are used in railway networks. As a result, one of the most important questions of the mangers involved in bridge managements systems (BMS) is how these changes affect the structural behavior of the critical components of the railway bridges. Although researchers have conducted, many investigations on the dynamic effects of the moving loads on bridges, the influence of the changes in the speed of the train on the demand by capacity ratios of the different critical components of the bridge have not yet been properly studied. This study is important, because different components with different capacities and roles for carrying loads in the structure may be affected differently. To investigate the above phenomenon in this research, a structural model of a simply supported bridge is developed. It will be verified that the dynamic behavior of this bridge is similar to a group of railway bridges in Australia. Demand by capacity ratios of the critical components of the bridge, when it is subjected to a train load with different speeds will be calculated. The results show that the effect of increase or decrease of speed should not be underestimated. The outcome is very significant as it is contrary to what is currently expected, i.e. by reducing the speed of the train, the demand by capacity ratio of components may increase and make the bridge unsafe for carrying live load.

In vitro functional characterisation of IGF-I : VN-induced breast cancer progression

Members of the insulin-like growth factor (IGF) family have been shown to play critical roles in normal growth and development, as well as in tumour biology. The IGF system is complex and the biological effects of the IGFs are determined by their diverse interactions between many molecules, including their interactions with extracellular matrix (ECM) proteins. Recent studies have demonstrated that IGFs associate with the ECM protein vitronectin (VN) through IGF-binding proteins (IGFBP) and that this interaction modulates IGF-stimulated biological functions, namely cell migration and cell survival through the cooperative involvement of the type-I IGF receptor (IGF-1R) and VN-binding integrins. Since IGFs play important roles in the transformation and progression of breast cancer and VN has been found to be over-expressed at the leading edge of breast tumours, this project aimed to describe the effects of IGF-I:VN interactions on breast cell function. This was undertaken to dissect the molecular mechanisms underlying IGF-I:VN-induced responses and to design inhibitors to block the effects of such interactions. The studies described herein demonstrate that the increase in migration of MCF-7 breast cancer cells in response to the IGF-I:IGFBP-5:VN complex is accompanied by differential expression of genes known to be involved in migration, invasion and/or survival, including Tissue-factor (TF), Stratifin (SFN), Ephrin-B2, Sharp-2 and PAI-1. This „migration gene signature‟ was confirmed using real-time PCR analysis. Substitution of the native IGF-I within the IGF-I:IGFBP:VN complex with the IGF-I analogue, \[L24]\[A31]-IGF-I, which has a reduced affinity for the IGF-1R, failed to stimulate cell migration and interestingly, also failed to induce the differential gene expression. This supports the involvement of the IGF-1R in mediating these changes in gene expression. Furthermore, lentiviral shRNA-mediated stable knockdown of TF and SFN completely abrogated the increased cell migration induced by IGF-I:IGFBP:VN complexes in MCF-7 cells. Indeed, when these cells were grown in 3D Matrigel™ cultures a decrease in the overall size of the 3D spheroids in response to the IGF-I:IGFBP:VN complexes was observed compared to the parental MCF-7 cells. This suggests that TF and SFN have a role in complex-stimulated cell survival. Moreover, signalling studies performed on cells with the reduced expression of either TF or SFN had a decreased IGF-1R activation, suggesting the involvement of signalling pathways downstream of IGF-1R in TF- and/or SFN-mediated cell migration and cell survival. Taken together, these studies provide evidence for a common mechanism activated downstream of the IGF-1R that induces the expression of the „migration gene signature‟ in response to the IGF-I:IGFBP:VN complex that confers breast cancer cells the propensity to migrate and survive. Given the functional significance of the interdependence of ECM and growth factor (GF) interactions in stimulating processes key to breast cancer progression, this project aimed at developing strategies to prevent such growth factor:ECM interactions in an effort to inhibit the downstream functional effects. This may result in the reduction in the levels of ECM-bound IGF-I present in close proximity to the cells, thereby leading to a reduction in the stimulation of IGF-1R present on the cell surface. Indeed, the inhibition of IGF-I-mediated effects through the disruption of its association with ECM would not alter the physiological levels of IGF-I and potentially only exert effects in situations where abnormal over expression of ECM proteins are found; namely carcinomas and hyperproliferative diseases. In summary, this PhD project has identified novel, innovative and realistic strategies that can be used in vitro to inhibit the functions exerted by the IGF-I:IGFBP:VN multiprotein complexes critical for cancer progression, with a potential to be translated into in vivo investigations. Furthermore, TF and SFN were found to mediate IGF-I:IGFBP:VN-induced effects, thereby revealing their potential to be used as therapeutic targets or as predictive biomarkers for the efficacy of IGF-1R targeting therapies in breast cancer patients. In addition to its therapeutic and clinical scope, this PhD project has significantly contributed to the understanding of the role of the IGF system in breast tumour biology by providing valuable new information on the mechanistic events underpinning IGF-I:VN-mediated effects on breast cell functions. Furthermore, this is the first instance where favourable binding sites for IGF-II, IGFBP-3 and IGFBP-5 on VN have been identified. Taken together, this study has functionally characterised the interactions between IGF-I and VN and through innovative strategies has provided a platform for the development of novel therapies targeting these interactions and their downstream effects.

In the blink of an eye : the circadian effects on ocular and subjective indices of driver sleepiness

Driver sleepiness contributes substantially to fatal and severe crashes and the contribution it makes to less serious crashes is likely to as great or greater. Currently, drivers’ awareness of sleepiness (subjective sleepiness) remains a critical component for the mitigation of sleep-related crashes. Nonetheless, numerous calls have been made for technological monitors of drivers’ physiological sleepiness levels so drivers can be ‘alerted’ when approaching high levels of sleepiness. Several physiological indices of sleepiness show potential as a reliable metric to monitor drivers’ sleepiness levels, with eye blink indices being a promising candidate. However, extensive evaluations of eye blink measures are lacking including the effects that the endogenous circadian rhythm can have on eye blinks. To examine the utility of ocular measures, 26 participants completed a simulated driving task while physiological measures of blink rate and duration were recorded after partial sleep restriction. To examine the circadian effects participants were randomly assigned to complete either a morning or an afternoon session of the driving task. The results show subjective sleepiness levels increased over the duration of the task. The blink duration index was sensitive to increases in sleepiness during morning testing, but was not sensitive during afternoon testing. This finding suggests that the utility of blink indices as a reliable metric for sleepiness are still far from specific. The subjective measures had the largest effect size when compared to the blink measures. Therefore, awareness of sleepiness still remains a critical factor for driver sleepiness and the mitigation of sleep-related crashes.

Mothers' perceptions of introducing solids to their infant at six months of age : identifying critical belief-based targets to promote adherence to current infant feeding guidelines

We investigated critical belief-based targets for promoting the introduction of solid foods to infants at six months. First-time mothers (N = 375) completed a Theory of Planned Behaviour belief-based questionnaire and follow-up questionnaire assessing the age the infant was first introduced to solids. Normative beliefs about partner/spouse (β = 0.16) and doctor (β = 0.22), and control beliefs about commercial baby foods available for infants before six months (β = −0.20), predicted introduction of solids at six months. Intervention programs should target these critical beliefs to promote mothers’ adherence to current infant feeding guidelines to introduce solids at around six months.

Faculty-librarian partnerships in Australian higher education : critical dimensions

Australian higher education is presently subject to a period of substantial change. The needs of the economy and workforce, together with the broader educational role of the university are leading to focus on lifelong learning as a tool for bringing together the apparently diverging needs of different groups. Within this broader context, the emphasis on lifelong learning and associated graduate capabilities is leading to opportunities for new partnerships between faculty and librarians, partnerships that bring the two groups together in ways that are helping to transform the experience of teaching and learning. This paper explores emerging partnerships in diverse areas, including research and scholarship, curriculum, policy, supervision, and staff development. They are in the early phases of development and result from a broad focus on the learning and information literacy needs of students, as opposed to a narrow focus on using the library and its information resources. Taken together, and viewed from a system-wide perspective, these partnerships reveal a complex dynamic that is deserving of wider attention across the Australian higher education system and internationally.

Shear-critical impact response of biaxially loaded reinforced concrete circular columns

A study on the vulnerability of biaxially loaded reinforced concrete (RC) circular columns in multi-story buildings under low- to medium-velocity impacts at shear-critical locations is presented. The study is based on a previously validated nonlinear explicit dynamic finite element (FE) modeling technique developed by the authors. The impact is simulated using force pulses generated from full-scale vehicle impact tests abundantly found in the literature with a view to quantifying the sensitivity of the design parameters of the RC columns under the typical impacts that are representative of the general vehicle population. The design parameters considered include the diameter and height of the column, the vertical steel ratio, the concrete grade, and the confinement effects. From the results of the simulations, empirical equations to quantify the critical impulses for the simplified design of the short, circular RC columns under the risk of shear-critical impacts are developed.

A Critical Perspective of the Indonesian Institutional Framework for PPP Toll Roads

The development of toll roads in Indonesia started around 1978. Initially, the management and development of toll roads sat directly under the Government of Indonesia (GoI) being undertaken through PT JasaMarga, a state owned enterprise specifically established to provide toll roads. Due to the slow growth and low capability of toll roads to fulfil infrastructure needs in the first ten years of operation (only 2.688kms/year), GoI changed its strategy in 1989 to one of using private sector participation for roads delivery through a Public Private Partnership (PPP) scheme. In this latter period, PT JasaMarga had two roles, both as regulator on behalf of the private sector as well as being the operator. However, from 1989 to 2004 the growth rate of toll roads actually decreased further to 2.300kms/year. Facing this challenge of low growth rate of toll roads, in 2004GoI changed the toll road management system and the role of regulator was returned to the Government through the establishment of the Toll Road Regulatory Agency (BPJT). GoI also amended the institutional framework to strengthen the toll road management system. Despite the introduction of this new institutional framework, the growth of toll roads still showed insignificant change. This problem in toll road development has generated an urgent need for research into this issue. The aim of the research is to understand the performance of the new institutional framework in enhancing PPP procured toll road development. The methodology of the research was to undertake a questionnaire survey distributed to private sector respondents involved in toll road development. The results of this study show that there are several problems inherent in the institutional framework, but the most significant problem comes from the uncertainty of the function of the strategic executive body in the land expropriation process.

(De)Constructing ADHD : Critical Guidance for Teachers and Teacher Educators

Attention Deficit Hyperactivity Disorder (ADHD) has achieved celebrity status in many Western countries, yet despite considerable effort to prove its existence as a “real” disorder, ADHD still suffers from a crisis of legitimacy. Nonetheless, diagnosis and prescription of medication has grown at a phenomenal rate since the late 1980s, particularly in Western culture. Numerous accounts exist explaining how the ADHD diagnosis functions as a convenient administrative loophole, providing schools with a medical explanation for school failure, medication to sedate the “problem” into submission, or the means to eject children from mainstream classrooms. This book provides a more holistic interpretation of how to respond to children who might otherwise be diagnosed with and medicated for “ADHD”—a diagnosis which, whether scientifically valid or not, is unhelpful within the confine of the school. Training teachers to recognise and identify “ADHD symptoms” or to understand the functions of restricted pharmaceuticals will only serve to increase the number of children diagnosed and the sale of psychoactive medications. Research has shown that such activities will not help those children learn, nor will it empower their classroom teachers to take responsibility for teaching such children well. This book seeks to provide school practitioners with knowledge that is useful within the educational context to improve the educational experiences and outcomes for children who might otherwise receive a diagnosis of ADHD.

Epistatic effects of potassium channel variation on cardiac repolarization and atrial fibrillation risk

Objectives The aim of this study was to evaluate the role of cardiac K+ channel gene variants in families with atrial fibrillation (AF). Background The K+ channels play a major role in atrial repolarization but single mutations in cardiac K+ channel genes are infrequently present in AF families. The collective effect of background K+ channel variants of varying prevalence and effect size on the atrial substrate for AF is largely unexplored. Methods Genes encoding the major cardiac K+ channels were resequenced in 80 AF probands. Nonsynonymous coding sequence variants identified in AF probands were evaluated in 240 control subjects. Novel variants were characterized using patch-clamp techniques and in silico modeling was performed using the Courtemanche atrial cell model. Results Nineteen nonsynonymous variants in 9 genes were found, including 11 rare variants. Rare variants were more frequent in AF probands (18.8% vs. 4.2%, p < 0.001), and the mean number of variants was greater (0.21 vs. 0.04, p < 0.001). The majority of K+ channel variants individually had modest functional effects. Modeling simulations to evaluate combinations of K+ channel variants of varying population frequency indicated that simultaneous small perturbations of multiple current densities had nonlinear interactions and could result in substantial (>30 ms) shortening or lengthening of action potential duration as well as increased dispersion of repolarization. Conclusions Families with AF show an excess of rare functional K+ channel gene variants of varying phenotypic effect size that may contribute to an atrial arrhythmogenic substrate. Atrial cell modeling is a useful tool to assess epistatic interactions between multiple variants.

A socially just rationale for an Australian curriculum? : a critical thematic policy analysis of political speeches in education (2007-2010)

In late 2007, newly elected Prime Minister Kevin Rudd placed education reform on centre stage as a key policy in the Labor Party's agenda for social reform in Australia. A major policy strategy within this 'Education Revolution' was the development of a national curriculum, the Australian Curriculum Within this political context, this study is an investigation into how social justice and equity have been used in political speeches to justify the need for, and the nature of, Australia's first official national curriculum. The aim is to provide understandings into what is said or not said; who is included or excluded, represented or misrepresented; for what purpose; and for whose benefit. The study investigates political speeches made by Education Ministers between 2008 and 201 0; that is, from the inception of the Australian Curriculum to the release of the Phase 1 F - 10 draft curriculum documents in English, mathematics, science and history. Curriculum development is defined here as an ongoing process of complex conversations. To contextualise the process of curriculum development within Australia, the thesis commences with an initial review of curriculum development in this nation over the past three decades. It then frames this review within contemporary curriculum theory; in particular it calls upon the work of William Pinar and the key notions of currere and reconceptualised curriculum. This contextualisation work is then used as a foundation to examine how social justice and equity have been represented in political speeches delivered by the respective Education Ministers Julia Gillard and Peter Garrett at key junctures of Australian Curriculum document releases. A critical thematic policy analysis is the approach used to examine selected official speech transcripts released by the ministerial media centre through the DEEWR website. This approach provides a way to enable insights and understandings of representations of social justice and equity issues in the policy agenda. Broader social implications are also discussed. The project develops an analytic framework that enables an investigation into the framing of social justice and equity issues such as inclusion, equality, quality education, sharing of resources and access to learning opportunities in political speeches aligned with the development of the Australian Curriculum Through this analysis, the study adopts a focus on constructions of educationally disadvantaged students and how the solutions of 'fixing' teachers and providing the 'right' curriculum are presented as resolutions to the perceived problem. In this way, it aims to work towards offering insights into political justifications for a national curriculum in Australia from a social justice perspective.