152 resultados para Ductile-to-brittle transition


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Work environments have previously been studied to identify the strategies, structures and processes which increase the likelihood of creativity, innovation and collaboration for productive workplaces. A number of perspectives have emerged which identify social and cognitive factors known to contribute to or to restrict innovation and collaboration. Recently more attention has been given to designing physical environments to encourage processes relevant to innovation such as creativity (McCoy & Evans, 2002) knowledge sharing (Hemlin, Allwood & Martin, 2008) and collaboration (Bozeman & Corley, 2004). Some attention has been given specifically to research and development environments (Boutellier et al, 2008) but little integration of this research has occurred. In the context of the construction of new purpose-built premises which will bring together under one roof separate public sector agencies engaged in research and development in agriculture, natural resource systems and the environment, this paper examines the extant literature and develops initial propositions for research relevant to the transition, collaboration and performance of research and development in new organizational environments where traditional boundaries have been redrawn.

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This volume is the second in a series that addresses change and development in the delivery of vocational and education programs in Queensland. A similar volume was published in 2007. Considerable change was foreshadowed for TAFE Queensland by the release of The Queensland Skill Plan (QSP) in 2006. This volume addresses implementation issues for the Actions identified in the QSP. The chapters focus on a breadth of issues that relate to the changing landscape for teaching and learning in TAFE Institutes. The incorporation of Information Communication Technologies (ICTs) and e-learning approaches into the delivery of training packages remain key foci for change, as was evident in the first volume of this series. The chapters also consider issues for some client groups in VET, as well as approaches to professional development to build the capabilities of staff for new teaching and learning environments. The chapter by Sandra Lawrence examines the professional development issues for staff across TAFE institutes in the implementation of the Learning Management System. Suzanne Walsh discusses the issues of new “learning spaces” and “Mode 2 learning in the re-development at Southbank Institute. The chapter by Angela Simpson focuses on VET in schools and school-to-work transition programs. Josie Drew, in her chapter, takes up the issues of embedding employability skills into the delivery of training packages through flexible delivery. The chapter by Colleen Hodgins focuses on the organisational challenges for Lead Institutes in relation to the professional development for TAFE educators in light of policy changes. Bradley Jones discusses the changing roles of libraries in VET contexts and their importance. He examines the adequacy of the VOCED database and reflects on the current nature, role, and practices of VET libraries. Finally, Piero Dametto discusses the pragmatics for TAFE educators in understanding the use of digital objects and learning objects within the LMS and LCMS systems that were presaged in the QSP. These papers were completed by the authors as a part of their postgraduate studies at QUT. The views reported are those of the authors and should not be attributed to the Queensland Department of Education, Training and the Arts. Donna Berthelsen Faculty of Education Queensland University of Technology

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Early and rich conversations with a range of stakeholders – academics, professionals and graduates in their early years of practice – quickly clarified that the singular challenge for most parties centres on the ways in which courses prepare graduates for the pace, diversity and flux of contemporary professional practice.---------In pursuing understanding of this central challenge this study has focused on new graduates in BED disciplines by canvassing their views and those of two other major stakeholder groups (academic staff and professional practitioners in the disciplines studied). The first crucial years of a young graduate’s life in the workforce are shaped by a number of factors including the quality of the transition-to-work experience. The quality of this life-shaping transition is dependent on a range of factors including the ways in which graduates are educated in universities, their personal developmental characteristics and those of the professional people around them and the preparedness of workplaces and other professional groups to guide new recruits through the transition experience. This study makes recommendations about how the variations in transition experience, resulting from the vagaries of all these factors across a range of worksites, may be better understood, perhaps normalised, and, at least, supported. . Early and rich conversations with a range of stakeholders – academics, professionals and graduates in their early years of practice – quickly clarified that the singular challenge for most parties centres on the ways in which courses prepare graduates for the pace, diversity and flux of contemporary professional practice. The study proceeded through literature review, focus group interviews, national online survey and workshops. Through all these methods a number of challenges and factors essential to the transition experience, and the quality of education which precedes it, were identified. Firstly the study found further evidence of the importance of higher-order graduate capabilities, namely, the development of judgment, critical enquiry and strategic thinking. Alongside these capabilities the importance of the development of emotional intelligence, particularly interpersonal and social skills, was stressed by all stakeholders. At the time of writing the global economic crisis was providing challenges to the sector and its young graduates. This phenomenon proved the value of the development of resilience and persistence in graduates, the education system was called upon by all stakeholders as a place where the future-proofing of neophytes would ensure that the unknown challenges of the future could also be confronted. The study found that the challenges of transition to work are best supported by authentic undergraduate experiences both on and off campus, inside and outside classrooms, and that commencing professional life is made easier for new graduates when university courses and workplace settings develop, sustain and support high standards and high expectations of students. All these findings indicate the importance of stakeholder expectations, roles and responsibilities in respect of the transition-to-work experience. Whilst full agreement about how these things should occur is not necessary, a process (amongst stakeholders) which seeks value alignment around transition through discussion, debate and agenda-setting would probably assist to address what is seen as a major challenge in built environment and design education.

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Actuators with deliberately added compliant elements in the transmission system are often described as improving the safety of the actuator at the detriment of the performance. We show that our variant of the Series Elastic Actuator topology, the Velocity Sourced Series Elastic Actuator, has well defined performance characteristics that make for improvements in safety and performance over conventional high impedance actuators. The improvement in performance was principally achieved by having tight velocity control of the DC motor that acts as the mechanical power source for the actuator. Results for performance are given for point to point transition times, while results for safety are based on empirical assessment of the Head Injury Criterion during collisions.

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The human-technology nexus is a strong focus of Information Systems (IS) research; however, very few studies have explored this phenomenon in anaesthesia. Anaesthesia has a long history of adoption of technological artifacts, ranging from early apparatus to present-day information systems such as electronic monitoring and pulse oximetry. This prevalence of technology in modern anaesthesia and the rich human-technology relationship provides a fertile empirical setting for IS research. This study employed a grounded theory approach that began with a broad initial guiding question and, through simultaneous data collection and analysis, uncovered a core category of technology appropriation. This emergent basic social process captures a central activity of anaesthestists and is supported by three major concepts: knowledge-directed medicine, complementary artifacts and culture of anaesthesia. The outcomes of this study are: (1) a substantive theory that integrates the aforementioned concepts and pertains to the research setting of anaesthesia and (2) a formal theory, which further develops the core category of appropriation from anaesthesia-specific to a broader, more general perspective. These outcomes fulfill the objective of a grounded theory study, being the formation of theory that describes and explains observed patterns in the empirical field. In generalizing the notion of appropriation, the formal theory is developed using the theories of Karl Marx. This Marxian model of technology appropriation is a three-tiered theoretical lens that examines appropriation behaviours at a highly abstract level, connecting the stages of natural, species and social being to the transition of a technology-as-artifact to a technology-in-use via the processes of perception, orientation and realization. The contributions of this research are two-fold: (1) the substantive model contributes to practice by providing a model that describes and explains the human-technology nexus in anaesthesia, and thereby offers potential predictive capabilities for designers and administrators to optimize future appropriations of new anaesthetic technological artifacts; and (2) the formal model contributes to research by drawing attention to the philosophical foundations of appropriation in the work of Marx, and subsequently expanding the current understanding of contemporary IS theories of adoption and appropriation.

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Where object-oriented languages deal with objects as described by classes, model-driven development uses models, as graphs of interconnected objects, described by metamodels. A number of new languages have been and continue to be developed for this model- based paradigm, both for model transformation and for general programming using models. Many of these use single-object approaches to typing, derived from solutions found in object-oriented systems, while others use metamodels as model types, but without a clear notion of polymorphism. Both of these approaches lead to brittle and overly restrictive reuse characteristics. In this paper we propose a simple extension to object-oriented typing to better cater for a model-oriented context, including a simple strategy for typing models as a collection of interconnected objects. We suggest extensions to existing type system formalisms to support these concepts and their manipulation. Using a simple example we show how this extended approach permits more flexible reuse, while preserving type safety.

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Background: The “Curriculum renewal in legal education” project has been funded by the Australian Learning and Teaching Council with the core objectives being the articulation of a set of final year curriculum design principles, and the development of a model of a transferable final year program. Through these principles and the development of the model, it is anticipated that the final year experience for law students will provide greater opportunity for them to understand the relevance of their learning, and will enhance their capacity to make decisions regarding their career path. Discussion / Argument: This paper reports on the project’s progress to date, and presents an argument for the inclusion of work integrated learning (WIL) as a component of the final year experience in undergraduate law programs. The project has identified that the two principal objectives of capstone experiences are to provide closure and to facilitate transition to post-university life. Reflective practice and Bruner’s spiral curriculum model are the central theoretical foundations by which these objectives can be achieved. Experiential learning is also increasingly seen as an essential element of a capstone experience. WIL is consistent with the objectives of capstones in focusing on the transition to professional practice and providing opportunities for reflection. However, the ability of WIL to meet all of the objectives of capstones, particularly closure and integration, may be limited. Conclusions / Implications: The paper posits that while WIL should be considered as a potential component of a capstone experience, educators should ensure that WIL is not equated with a capstone experience unless it is carefully designed to ensure that all of the objectives of capstones are met. Keywords: Work-integrated learning, capstone, final year experience, law

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Purpose: Although there is increasing evidence that the creative industries are essential to national economic growth as well as social and cultural well-being, creative graduates often find it difficult to become established professionally. This study investigates the value of career management competence and intrinsic career motivations (as elements of ‘protean career orientation’) in predicting positive graduate outcomes. ----- ----- Design/methodology: Self-report surveys were administered to 208 creative industries graduates from two Australian universities at two points in time: at course completion, and one year later. ----- ----- Findings: Individual career management competence and intrinsic work motivations, measured at course completion, were significant predictors of early career success, using both subjective and objective measures, measured one year later. ----- ----- Practical implications: This study suggests that an emphasis on student development beyond the traditional ‘key’ employability skills may well be worthwhile. The article also suggests a broad learning and teaching approach by which universities can encourage the development of student career identity, and thus engender student intrinsic career motivations and career self management skills and behaviours. ----- ----- Originality/value: This is one of the first studies to demonstrate empirically a link between a particular set of skills and graduate outcomes. In addition, it provides insights into the role of student career motivations in positive transitions to the world of work in the creative industries.

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A number of reports have demonstrated the importance of the CUB domaincontaining protein 1 (CDCP1) in facilitating cancer progression in animal models and the potential of this protein as a prognostic marker in several malignancies. CDCP1 facilitates metastasis formation in animal models by negatively regulating anoikis, a type of apoptosis triggered by the loss of attachment signalling from cell-cell contacts or cell-extra cellular matrix (ECM) contacts. Due to the important role CDCP1 plays in cancer progression in model systems, it is considered a potential drug target to prevent the metastatic spread of cancers. CDCP1 is a highly glycosylated 836 amino acid cell surface protein. It has structural features potentially facilitating protein-protein interactions including 14 N-glycosylation sites, three CUB-like domains, 20 cysteine residues likely to be involved in disulfide bond formation and five intracellular tyrosine residues. CDCP1 interacts with a variety of proteins including Src family kinases (SFKs) and protein kinase C ä (PKCä). Efforts to understand the mechanisms regulating these interactions have largely focussed on three CDCP1 tyrosine residues Y734, Y743 and Y762. CDCP1-Y734 is the site where SFKs phosphorylate and bind to CDCP1 and mediate subsequent phosphorylation of CDCP1-Y743 and -Y762 which leads to binding of PKCä at CDCP1-Y762. The resulting trimeric protein complex of SFK•CDCP1•PKCä has been proposed to mediate an anti-apoptotic cell phenotype in vitro, and to promote metastasis in vivo. The effect of mutation of the three tyrosines on interactions of CDCP1 with SFKs and PKCä and the consequences on cell phenotype in vitro and in vivo have not been examined. CDCP1 has a predicted molecular weight of ~90 kDa but is usually detected as a protein which migrates at ~135 kDa by Western blot analysis due to its high degree of glycosylation. A low molecular weight form of CDCP1 (LMWCDCP1) of ~70 kDa has been found in a variety of cancer cell lines. The mechanisms leading to the generation of LMW-CDCP1 in vivo are not well understood but an involvement of proteases in this process has been proposed. Serine proteases including plasmin and trypsin are able to proteolytically process CDCP1. In addition, the recombinant protease domain of the serine protease matriptase is also able to cleave the recombinant extracellular portion of CDCP1. Whether matriptase is able to proteolytically process CDCP1 on the cell surface has not been examined. Importantly, proteolytic processing of CDCP1 by trypsin leads to phosphorylation of its cell surface-retained portion which suggests that this event leads to initiation of an intracellular signalling cascade. This project aimed to further examine the biology of CDCP1 with a main of focus on exploring the roles played by CDCP1 tyrosine residues. To achieve this HeLa cells stably expressing CDCP1 or the CDCP1 tyrosine mutants Y734F, Y743F and Y762F were generated. These cell lines were used to examine: • The roles of the tyrosine residues Y734, Y743 and Y762 in mediating interactions of CDCP1 with binding proteins and to examine the effect of the stable expression on HeLa cell morphology. • The ability of the serine protease matriptase to proteolytically process cell surface CDCP1 and to examine the consequences of this event on HeLa cell phenotype and cell signalling in vitro. • The importance of these residues in processes associated with cancer progression in vitro including adhesion, proliferation and migration. • The role of these residues on metastatic phenotype in vivo and the ability of a function-blocking anti-CDCP1 antibody to inhibit metastasis in the chicken embryo chorioallantoic membrane (CAM) assay. Interestingly, biochemical experiments carried out in this study revealed that mutation of certain CDCP1 tyrosine residues impacts on interactions of this protein with binding proteins. For example, binding of SFKs as well as PKCä to CDCP1 was markedly decreased in HeLa-CDCP1-Y734F cells, and binding of PKCä was also reduced in HeLa-CDCP1-Y762F cells. In contrast, HeLa-CDCP1-Y743F cells did not display altered interactions with CDCP1 binding proteins. Importantly, observed differences in interactions of CDCP1 with binding partners impacted on basal phosphorylation of CDCP1. It was found that HeLa-CDCP1, HeLa-CDCP1-Y743F and -Y762F displayed strong basal levels of CDCP1 phosphorylation. In contrast, HeLa-CDCP1-Y734F cells did not display CDCP1 phosphorylation but exhibited constitutive phosphorylation of focal adhesion kinase (FAK) at tyrosine 861. Significantly, subsequent investigations to examine this observation suggested that CDCP1-Y734 and FAK-Y861 are competitive substrates for SFK-mediated phosphorylation. It appeared that SFK-mediated phosphorylation of CDCP1- Y734 and FAK-Y861 is an equilibrium which shifts depending on the level of CDCP1 expression in HeLa cells. This suggests that the level of CDCP1 expression may act as a regulatory mechanism allowing cells to switch from a FAK-Y861 mediated pathway to a CDCP1-Y734 mediated pathway. This is the first time that a link between SFKs, CDCP1 and FAK has been demonstrated. One of the most interesting observations from this work was that CDCP1 altered HeLa cell morphology causing an elongated and fibroblastic-like appearance. Importantly, this morphological change depended on CDCP1- Y734. In addition, it was observed that this change in cell morphology was accompanied by increased phosphorylation of SFK-Y416. This suggests that interactions of SFKs with CDCP1-Y734 increases SFK activity since SFKY416 is critical in regulating kinase activity of these proteins. The essential role of SFKs in mediating CDCP1-induced HeLa cell morphological changes was demonstrated using the SFK-selective inhibitor SU6656. This inhibitor caused reversion of HeLa-CDCP1 cell morphology to an epithelial appearance characteristic of HeLa-vector cells. Significantly, in vitro studies revealed that certain CDCP1-mediated cell phenotypes are mediated by cellular pathways dependent on CDCP1 tyrosine residues whereas others are independent of these sites. For example, CDCP1 expression caused a marked increase in HeLa cell motility that was independent of CDCP1 tyrosine residues. In contrast, CDCP1- induced decrease in HeLa cell proliferation was most prominent in HeLa- CDCP1-Y762F cells, potentially indicating a role for this site in regulating proliferation in HeLa cells. Another cellular event which was identified to require phosphorylation of a particular CDCP1 tyrosine residue is adhesion to fibronectin. It was observed that the CDCP1-mediated strong decrease in adhesion to fibronectin is mostly restored in HeLa-CDCP1-Y743F cells. This suggests a possible role for CDCP1-Y743 in causing a CDCP1-mediated decrease in adhesion. Data from in vivo experiments indicated that HeLa-CDCP1-Y734F cells are more metastic than HeLa-CDCP1 cells in vivo. This indicates that interaction of CDCP1 with SFKs and PKCä may not be required for CDCP1-mediated metastasis formation of HeLa cells in vivo. The metastatic phenotype of these cells may be caused by signalling involving FAK since HeLa-CDCP1- Y734F cells are the only CDCP1 expressing cells displaying constitutive phosphorylation of FAK-Y861. HeLa-CDCP1-Y762F cells displayed a very low metastatic ability which suggests that this CDCP1 tyrosine residue is important in mediating a pro-metastatic phenotype in HeLa cells. More detailed exploration of cellular events occurring downstream of CDCP1-Y734 and -Y762 may provide important insights into the mechanisms altering the metastatic ability of CDCP1 expressing HeLa cells. Complementing the in vivo studies, anti-CDCP1 antibodies were employed to assess whether these antibodies are able to inhibit metastasis of CDCP1 and CDCP1 tyrosine mutants expressing HeLa cells. It was found that HeLa- CDCP1-Y734F cells were the only cell line which was markedly reduced in the ability to metastasise. In contrast, the ability of HeLa-CDCP1, HeLa- CDCP1-Y743F and -Y762F cells to metastasise in vivo was not inhibited. These data suggest a possible role of interactions of CDCP1 with SFKs, occurring at CDCP1-Y734, in preventing an anti-metastatic effect of anti- CDCP1 antibodies in vivo. The proposal that SFKs may play a role in regulating anti-metastatic effects of anti-CDCP1 antibodies was supported by another experiment where differences between HeLa-CDCP1 cells and CDCP1 expressing HeLa cells (HeLa-CDCP1-S) from collaborators at the Scripps Research Institute were examined. It was found that HeLa-CDCP1-S cells express different SFKs than CDCP1 expressing HeLa cells generated for this study. This is important since HeLa-CDCP1-S cells can be inhibited in their metastatic ability using anti-CDCP1 antibodies in vivo. Importantly, these data suggest that further examinations of the roles of SFKs in facilitating anti-metastatic effects of anti-CDCP1 antibodies may give insights into how CDCP1 can be blocked to prevent metastasis in vivo. This project also explored the ability of the serine protease matriptase to proteolytically process cell surface localised CDCP1 because it is unknown whether matriptase can cleave cell surface CDCP1 as it has been reported for other proteases such as trypsin and plasmin. Furthermore, the consequences of matriptase-mediated proteolysis on cell phenotype in vitro and cell signalling were examined since recent reports suggested that proteolysis of CDCP1 leads to its phosphorylation and may initiate cell signalling and consequently alter cell phenotype. It was found that matriptase is able to proteolytically process cell surface CDCP1 at low nanomolar concentrations which suggests that cleavage of CDCP1 by matriptase may facilitate the generation of LWM-CDCP1 in vivo. To examine whether matriptase-mediated proteolysis induced cell signalling anti-phospho Erk 1/2 Western blot analysis was performed as this pathway has previously been examined to study signalling in response to proteolytic processing of cell surface proteins. It was found that matriptase-mediated proteolysis in CDCP1 expressing HeLa cells initiated intracellular signalling via Erk 1/2. Interestingly, this increase in phosphorylation of Erk 1/2 was also observed in HeLa-vector cells. This suggested that initiation of cell signalling via Erk 1/2 phosphorylation as a result of matriptase-mediated proteolysis occurs by pathways independent of CDCP1. Subsequent investigations measuring the flux of free calcium ions and by using a protease-activated receptor 2 (PAR2) agonist peptide confirmed this hypothesis. These data suggested that matriptase-mediated proteolysis results in cell signalling via a pathway induced by the activation of PAR2 rather than by CDCP1. This indicates that induction of cell signalling in HeLa cells as a consequence of matriptase-mediated proteolysis occurs via signalling pathways which do not involve phosphorylation of Erk 1/2. Consequently, it appears that future attempts should focus on the examination of cellular pathways other than Erk 1/2 to elucidate cell signalling initiated by matriptase-mediated proteolytic processing of CDCP1. The data presented in this thesis has explored in vitro and in vivo aspects of the biology of CDCP1. The observations summarised above will permit the design of future studies to more precisely determine the role of CDCP1 and its binding partners in processes relevant to cancer progression. This may contribute to further defining CDCP1 as a target for cancer treatment.

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This paper describes algorithms that can musically augment the realtime performance of electronic dance music by generating new musical material by morphing. Note sequence morphing involves the algorithmic generation of music that smoothly transitions between two existing musical segments. The potential of musical morphing in electronic dance music is outlined and previous research is summarised; including discussions of relevant music theoretic and algorithmic concepts. An outline and explanation is provided of a novel Markov morphing process that uses similarity measures to construct transition matrices. The paper reports on a ‘focus-concert’ study used to evaluate this morphing algorithm and to compare its output with performances from a professional DJ. Discussions of this trial include reflections on some of the aesthetic characteristics of note sequence morphing. The research suggests that the proposed morphing technique could be effectively used in some electronic dance music contexts.

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In the last decade, a gradual but significant shift in education has taken place. Schools have transformed from hermetically sealed, impermeable bureaucracies to dynamic and flexible organisations characterised by openness to local communities and connectedness to global issues and cultures. They are also more responsive to the aspirations of students and parents. A central feature of what Christian Maroy (2009) has described as the post bureaucratic era of education has been the relationships formed between schools and other organisations through formalised partnerships. Partnerships have been a significant feature of schooling in Queensland since the 1980s when schools developed Vocational Education Programs (VET) providing alternative pathways from schooling to post school training or employment. However, partnerships that have emerged in recent times have been more structured in their organisation and more targeted in terms of the outcomes they aim to achieve. Examples here have included Queensland’s District Youth Achievement plans that linked schools, business, industry bodies, training organisations and community groups to improve transition outcomes, particularly for young people at risk in their transitions from school to post-school life.

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Like a set of bookends, cellular, molecular, and genetic changes of the beginnings of life mirror those of one of the most common cause of death—metastatic cancer. Epithelial to mesenchymal transition (EMT) is an important change in cell phenotype which allows the escape of epithelial cells from the structural constraints imposed by tissue architecture, and was first recognized by Elizabeth Hay in the early to mid 1980's to be a central process in early embryonic morphogenesis. Reversals of these changes, termed mesenchymal to epithelial transitions (METs), also occur and are important in tissue construction in normal development. Over the last decade, evidence has mounted for EMT as the means through which solid tissue epithelial cancers invade and metastasize. However, demonstrating this potentially rapid and transient process in vivo has proven difficult and data connecting the relevance of this process to tumor progression is still somewhat limited and controversial. Evidence for an important role of MET in the development of clinically overt metastases is starting to accumulate, and model systems have been developed. This review details recent advances in the knowledge of EMT as it occurs in breast development and carcinoma and prostate cancer progression, and highlights the role that MET plays in cancer metastasis. Finally, perspectives from a clinical and translational viewpoint are discussed

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Germline mutations within the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene and one of its targets, the cyclin dependent kinase 4 (CDK4) gene, have been identified in a proportion of melanoma kindreds. In the case of CDK4, only one specific mutation, resulting in the substitution of a cysteine for an arginine at codon 24 (R24C), has been found to be associated with melanoma. We have previously reported the identification of germline CDKN2A mutations in 7/18 Australian melanoma kindreds and the absence of the R24C CDK4 mutation in 21 families lacking evidence of a CDKN2A mutation. The current study represents an expansion of these efforts and includes a total of 48 melanoma families from Australia. All of these families have now been screened for mutations within CDKN2A and CDK4, as well as for mutations within the CDKN2A homolog and 9p21 neighbor, the CDKN2B gene, and the alternative exon 1 (E1beta) of CDKN2A. Families lacking CDKN2A mutations, but positive for a polymorphism(s) within this gene, were further evaluated to determine if their disease was associated with transcriptional silencing of one CDKN2A allele. Overall, CDKN2A mutations were detected in 3/30 (10%) of the new kindreds. Two of these mutations have been observed previously: a 24 bp duplication at the 5' end of the gene and a G to C transversion in exon 2 resulting in an M531 substitution. A novel G to A transition in exon 2, resulting in a D108N substitution was also detected. Combined with our previous findings, we have now detected germline CDKN2A mutations in 10/48 (21%) of our melanoma kindreds. In none of the 'CDKN2A-negative' families was melanoma found to segregate with either an untranscribed CDKN2A allele, an R24C CDK4 mutation, a CDKN2B mutation, or an E1beta mutation. The last three observations suggest that these other cell cycle control genes (or alternative gene products) are either not involved at all, or to any great extent, in melanoma predisposition.

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Ecological sustainability has been proposed to address the problem of human impacts increasingly degrading planetary resources and ecosystems, threatening biodiversity, eco-services and human survival. Ecological sustainability is an imperative, with Australia having one of the highest eco-footprints per person worldwide. While significant progress has been made via implementation of ecologically sustainable design in urban communities, relatively little has been undertaken in small, disparate regional communities in Australia. Regional communities are disadvantaged by rural economic decline associated with structural change and inequities of resource transfer. The ecologically sustainable solution is holistic, so all settlements need to be globally wise, richly biodiverse yet locally specific. As a regional solution to this global problem, this research offers the practical means by which a small regional community can contribute. It focuses on the design and implementation of a community centre and the fostering of transformative community learning through an integrated ‘learning community’ awareness of ecologically sustainable best practice. Lessons learned are documented by the participant researcher who as a designer, facilitator, local resident and social narrator has been deeply connected with the Tweed-Caldera region over a period since 1980. The collective action of the local community of Chillingham has been diligently recorded over a decade of design and development. Over this period, several positive elements emerged in terms of improvements to the natural and built environment, greater social cohesion and co-operative learning along with a shift towards a greener local economy. Behavioural changes in the community were noted as residents strived to embrace ecological ideals and reduce fossil fuel dependency. They found attractive local solutions to sourcing of food and using local employment opportunities to up skill their residents via transformative learning as a community in transition. Finally, the catalytic impact of external partnering has also been documented. How well the region as a whole has achieved its ecologically sustainable objectives is measured in terms of the delivered success of private and public partnering with the community, the creation of a community centre cum environment education centre, the restoration of local heritage buildings, the repair of riparian forests and improved water conditions in local river systems, better roads and road safety, local skills and knowledge transfer, support of local food and local/regional growers markets to attract tourists via the integrated trails network. In aggregate, each and every element contributes to a measure of eco-positive development for the built environment, its social organisation and its economy that has guided the local community to find its own pathway to sustainability. Within the Tweed-Caldera bioregion in northern New South Wales, there has been a lack of strategic planning, ecologically sustainable knowledge and facilities in isolated communities that could support the development of a local sustained green economy, provide a hub for socio-cultural activities and ecology based education. The first challenge in this research was to model a whole systems approach to eco-positive development in Chillingham, NSW, a small community where Nature and humanity know no specific boundary. The net result was the creation of a community environment education centre featuring best-affordable ecological practice and regionally distinctive, educational building form from a disused heritage building (cow bale). This development, implemented over a decade, resonated with the later regional wide programs that were linked in the Caldera region by the common purpose of extending the reach of local and state government assistance to regional NSW in economic transition coupled with sustainability. The lessons learned from these linked projects reveal that subsequent programs have been significantly easier to initiate, manage, develop and deliver results. In particular, pursuing collaborative networks with all levels of government and external private partners has been economically effective. Each community’s uniqueness has been celebrated and through drawing out these distinctions, has highlighted local vision, strategic planning, sense of belonging and connection of people with place. This step has significantly reduced the level of friction between communities that comes from natural competition for the finite pool of funds. Following the pilot Tweed-Caldera study, several other NSW regional communities are now undertaking a Community Economic Transition Program based on the processes, trials and positive experiences witnessed in the Tweed-Caldera region where it has been demonstrated that regional community transition programs can provide an opportunity to plan and implement effective long term strategies for sustainability, empowering communities to participate in eco-governance. This thesis includes the design and development of a framework for community created environment education centres to provide an equal access place for community to participate to meet their essential needs locally. An environment centre that facilitates community transition based on easily accessible environmental education, skills and infrastructure is necessary to develop local cultures of sustainability. This research draws upon the literatures of ecologically sustainable development, environmental education and community development in the context of regional community transition towards ‘strong sustainability’. The research approach adapted is best described as a four stage collaborative action research cycle where the participant researcher (me) has a significant involvement in the process to foster local cultures of sustainability by empowering its citizens to act locally and in doing so, become more self reliant and socially resilient. This research also draws upon the many fine working exemplars, such as the resilience of the Cuban people, the transition town initiative in Totnes, U.K. and the models of Australian Community Gardens, such as CERES (Melbourne) and Northey Street (Brisbane). The objectives of this study are to research and evaluate exemplars of ecologically sustainable environment education centres, to facilitate the design and development of an environment education centre created by a small regional community as an ecologically sustainable learning environment; to facilitate a framework for community transition based on environmental education, skills and infrastructure necessary to develop local cultures of sustainability. The research was undertaken as action research in the Tweed Caldera in Northern NSW. This involved the author as participant researcher, designer and volunteer in two interconnected initiatives: the Chillingham Community Centre development and the Caldera Economic Transition Program (CETP). Both initiatives involved a series of design-led participatory community workshops that were externally facilitated with the support of government agency partnerships, steering committees and local volunteers. Together the Caldera research programs involved communities participating in developing their own strategic planning process and outcomes. The Chillingham Community Centre was developed as a sustainable community centre/hub using a participatory design process. The Caldera Economic Transition Program (CETP) prioritised Caldera region projects: the Caldera farmer’s market; community gardens and community kitchens; community renewable energy systems and an integrated trails network. The significant findings were: the CETP projects were capable of moving towards an eco-positive design benchmark through transformative learning. Community transition to sustainability programs need to be underpinned by sustainability and environmental education based frameworks and practical on ground experience in local needs based projects through transformative learning. The actioned projects were successfully undertaken through community participation and teamwork. Ecological footprint surveys were undertaken to guide and assess the ongoing community transition process, however the paucity of responses needs to be revisited. The concept of ecologically sustainable development has been adopted internationally, however existing design and planning strategies do not assure future generations continued access to healthy natural life support systems. Sustainable design research has usually been urban focussed, with little attention paid to regional communities. This study seeks to redress this paucity through the design of ecologically sustainable (deep green) learning environments for small regional communities. Through a design-led process of environmental education, this study investigates how regional communities can be facilitated to model the principles of eco-positive development to support transition to local cultures of sustainability. This research shows how community transition processes and projects can incorporate sustainable community development as transformative learning through design. Regional community transition programs can provide an opportunity to plan long term strategies for sustainability, empowering people to participate in eco-governance. A framework is developed for a community created environment education centre to provide an equal access place for the local community to participate in implementing ways to meet their essential needs locally. A community environment education centre that facilitates community transition based on holistic environmental education, skills and infrastructure is necessary to develop local cultures of sustainability.