Clinoenstatite coatings have high bonding strength, bioactive ion release, and osteoimmunomodulatory effects that enhance in vivo osseointegration

A number of coating materials have been developed over past two decades seeking to improve the osseointegration of orthopedic metal implants. Despite the many candidate materials trialed, their low rate of translation into clinical applications suggests there is room for improving the current strategies for their development. We therefore propose that the ideal coating material(s) should possess the following three properties: (i) high bonding strength, (ii) release of functional ions, and (iii) favourable osteoimmunomodulatory effects. To test this proposal, we developed clinoenstatite (CLT, MgSiO3), which as a coating material has high bonding strength, cytocompability and immunomodulatory effects that are favourable for in vivo osteogenesis. The bonding strength of CLT coatings was 50.1 ± 3.2 MPa, more than twice that of hydroxyapatite (HA) coatings, at 23.5 ± 3.5 MPa. CLT coatings released Mg and Si ions, and compared to HA coatings, induced an immunomodulation more conducive for osseointegration, demonstrated by downregurelation of pro-inflammatory cytokines, enhancement of osteogenesis, and inhibition of osteoclastogenesis. In vivo studies demonstrated that CLT coatings improved osseointegration with host bone, as shown by the enhanced biomechanical strength and increased de novo bone formation, when compared with HA coatings. These results support the notion that coating materials with the proposed properties can induce an in vivo environment better suited for osseointegration. These properties could, therefore, be fundamental when developing high-performance coating materials.

Reflective practice as a tool for addressing high levels of psychological distress in Australian law schools and the legal profession

This paper discusses: -The need for law schools to use curriculum as a site for positive interventions to support student psychological well-being. -The potential for law school interventions to impact on the psychological well-being of the profession. -Reflective practice as a possible tool for promoting psychological well-being in law school and the profession because it provides a way of coping with ‘indeterminate zones’ of experience.

High-performance graphene-based supercapacitors made by a scalable blade-coating approach

Graphene oxide (GO) sheets can form liquid crystals (LCs) in their aqueous dispersions that are more viscous with a stronger LC feature. In this work we combine the viscous LC-GO solution with the blade-coating technique to make GO films, for constructing graphene-based supercapacitors in a scalable way. Reduced GO (rGO) films are prepared by wet chemical methods, using either hydrazine (HZ) or hydroiodic acid (HI). Solid-state supercapacitors with rGO films as electrodes and highly conductive carbon nanotube films as current collectors are fabricated and the capacitive properties of different rGO films are compared. It is found that the HZ-rGO film is superior to the HI-rGO film in achieving high capacitance, owing to the 3D structure of graphene sheets in the electrode. Compared to gelled electrolyte, the use of liquid electrolyte (H2SO4) can further increase the capacitance to 265 F per gram (corresponding to 52 mF per cm2) of the HZ-rGO film.

Metal oxide nanofibres membranes assembled by spin-coating method

Ceramic membranes are of particular interest in many industrial processes due to their ability to function under extreme conditions while maintaining their chemical and thermal stability. Major structural deficiencies under conventional fabrication approach are pin-holes and cracks, and the dramatic losses of flux when pore sizes are reduced to enhance selectivity. We overcome these structural deficiencies by constructing hierarchically structured separation layer on a porous substrate using larger titanate nanofibres and smaller boehmite nanofibres. This yields a radical change in membrane texture. The differences in the porous supports have no substantial influences on the texture of resulting membranes. The membranes with top layer of nanofibres coated on different porous supports by spin-coating method have similar size of the filtration pores, which is in a range of 10–100 nm. These membranes are able to effectively filter out species larger than 60 nm at flow rates orders of magnitude greater than conventional membranes. The retention can attain more than 95%, while maintaining a high flux rate about 900 L m-2 h. The calcination after spin-coating creates solid linkages between the fibres and between fibres and substrate, in addition to convert boehmite into -alumina nanofibres. This reveals a new direction in membrane fabrication.

Coating of biomaterial scaffolds with the collagen-mimetic peptide GFOGER for bone defect repair

Healing large bone defects and non-unions remains a significant clinical problem. Current treatments, consisting of auto and allografts, are limited by donor supply and morbidity, insufficient bioactivity and risk of infection. Biotherapeutics, including cells, genes and proteins, represent promising alternative therapies, but these strategies are limited by technical roadblocks to biotherapeutic delivery, cell sourcing, high cost, and regulatory hurdles. In the present study, the collagen-mimetic peptide, GFOGER, was used to coat synthetic PCL scaffolds to promote bone formation in critically-sized segmental defects in rats. GFOGER is a synthetic triple helical peptide that binds to the [alpha]2[beta]1 integrin receptor involved in osteogenesis. GFOGER coatings passively adsorbed onto polymeric scaffolds, in the absence of exogenous cells or growth factors, significantly accelerated and increased bone formation in non-healing femoral defects compared to uncoated scaffolds and empty defects. Despite differences in bone volume, no differences in torsional strength were detected after 12 weeks, indicating that bone mass but not bone quality was improved in this model. This work demonstrates a simple, cell/growth factor-free strategy to promote bone formation in challenging, non-healing bone defects. This biomaterial coating strategy represents a cost-effective and facile approach, translatable into a robust clinical therapy for musculoskeletal applications.

Improving reflective writing in higher education : A social semiotic perspective

Reflective skills are widely regarded as a means of improving students’ lifelong learning and professional practice in higher education (Rogers 2001). While the value of reflective practice is widely accepted in educational circles, a critical issue is that reflective writing is complex, and has high rhetorical demands, making it difficult to master unless it is taught in an explicit and systematic way. This paper argues that a functional-semantic approach to language (Eggins 2004), based on Halliday’s (1978) systemic functional linguistics can be used to develop a shared language to explicitly teach and assess reflective writing in higher education courses. The paper outlines key theories and scales of reflection, and then uses systemic functional linguistics to develop a social semiotic model for reflective writing. Examples of reflective writing are analysed to show how such a model can be used explicitly to improve the reflective writing skills of higher education students.

Bonding of aluminum alloy by hot-dipping tin coating

This paper presents bonding technology of aluminum alloy by hot-dipping tin. The dissolution curve of copper in molten tin liquid was obtained in the experiment of hot-dipping Sn. Optimal hot-dipping parameter which was suitable for soldering was designed. To elucidate characteristics of interfacial evolution, the microstructure of the coatings, soldered joint were analyzed using optical microscopy, SEM and EDX. The shear strength of soldered joints was tested as high as 39.9Mpa, which is high enough to achieve the requirement of electronic industry.

Porous zirconia scaffold modified with mesoporous bioglass coating

Porous yttria-stabilized zirconia (YSZ) has been regarded as a potential candidate for bone substitute as its high mechanical strength. However, porous YSZ bodies are biologically inert to bone tissue. It is therefore necessary to introduce bioactive coatings onto the walls of the porous structures to enhance the bioactivity. In this study, the porous zirconia scaffolds were prepared by infiltration of Acrylonitrile Butadiene Styrene (ABS) scaffolds with 3 mol% yttria stabilized zirconia slurry. After sintering, a method of sol-gel dip coating was involved to make coating layer of mesoporous bioglass (MBGs). The porous zirconia without the coating had high porosities of 60.1% to 63.8%, and most macropores were interconnected with pore sizes of 0.5-0.8mm. The porous zirconia had compressive strengths of 9.07-9.90MPa. Moreover, the average coating thickness was about 7μm. There is no significant change of compressive strength for the porous zirconia with mesoporous biogalss coating. The bone marrow stromal cell (BMSC) proliferation test showed both uncoated and coated zirconia scaffolds have good biocompatibility. The scanning electron microscope (SEM) micrographs and the compositional analysis graphs demonstrated that after testing in the simulated body fluid (SBF) for 7 days, the apatite formation occurred on the coating surface. Thus, porous zirconia-based ceramics were modified with bioactive coating of mesoporous bioglass for potential biomedical applications.

Digital Storytelling within a Service-Learning Partnership: Technology as Product and Process for University Students and Culturally and Linguistically Diverse High School Youth

This chapter describes a university/high school partnership focused on digital storytelling. It also explains the multi-stage process used to establish this successful partnership and project. The authors discuss the central role that technology played in developing this university/high school partnership, a collaboration that extended the impact of a digital storytelling project to reach high school students, university students, educators, high school administrators, and the local community. Valuing a reflective process that can lead to the creation of a powerful final product, the authors describe the impact of digital storytelling on multiple stakeholders, including the 13 university students and 33 culturally and linguistically diverse high school youth who participated during the fall of 2009. In addition, the chapter includes reflections from university and high school student participants expressed during focus groups conducted throughout the project. While most participants had a positive experience with the project, complications with the technology component often caused frustrations and additional challenges. Goals for sharing this project are to critically evaluate digital storytelling, describe lessons learned, and recommend good practices for others working within a similar context or with parallel goals.

The Socratic classroom : reflective thinking through collaborative inquiry

This book was written to serve two functions. First it is an exploration of what I have called Socratic pedagogy, a collaborative inquiry-based approach to teaching and learning suitable not only to formal educational settings such as the school classroom but to all educational settings. The term is intended to capture a variety of philosophical approaches to classroom practice that could broadly be described Socratic in form. The term ‘philosophy in schools’ is ambiguous and could refer to teaching university style philosophy to high school students or to the teaching of philosophy and logic or critical reasoning in senior years of high school. It is also used to describe the teaching of philosophy in schools generally. In the early and middle phases of schooling the term philosophy for children is often used. But this too is ambiguous as the name was adopted from Matthew Lipman’s Philosophy for Children curriculum that he and his colleagues at the Institute for the Advancement of Philosophy for Children developed. In Britain the term ‘philosophy with children’ is sometimes employed to mark two methods of teaching that have Socratic roots but have distinct differences, namely Philosophy for Children and Socratic Dialogue developed by Leonard Nelson. The use of the term Socratic pedagogy and its companion term Socratic classroom (to refer to the kind of classroom that employs Socratic teaching) avoids the problem of distinguishing between various approaches to philosophical inquiry in the Socratic tradition but also separates it from the ‘study of philosophy’, such as university style philosophy or other approaches which place little or no emphasis on collaborative inquiry based teaching and learning. The second function builds from the first. It is to develop an effective framework for understanding the relationship between what I call the generative, evaluative and connective aspects of communal dialogue, which I think are necessary to the Socratic notion of inquiry. In doing so it is hoped that this book offers some way to show how philosophy as inquiry can contribute to educational theory and practice, while also demonstrating how it can be an effective way to approach teaching and learning. This has meant striking a balance between speaking to philosophers and to teachers and educators together, with the view that both see the virtues of such a project. In the strictest sense this book is not philosophy of education, insofar as its chief focus is not on the analysis of concepts or formulation of definitions specific to education with the aim of formulating directives that guide educational practice. It relinquishes the role of philosopher as ‘spectator’, to one of philosopher ‘immersed in matter’ – in this case philosophical issues in education, specifically those related to philosophical inquiry, pedagogy and classroom practice. Put another way, it is a book about philosophical education.

Preparing high achieving English teachers to work in disadvantaged schools : 'I'll teach Shakespeare when I'm 60'

The recent release of the Gonski Review recognises the decline in Australia’s schooling performances over the last decade, noting in particular a distressing increase in the ‘achievement gap’ affecting students from low SES backgrounds (Gonski, 2012). The report details the need for more quality in teachers throughout the schooling system, particularly within the schools with the greatest academic needs. This paper specifically focuses on a group of high-achieving pre-service English teachers. In their last two years of university study, they participated in a program called Exceptional Teachers for Disadvantaged Schools (ETDS), designed to prepare them to work in disadvantaged or low SES schools. We wanted to capture their experiences of teaching in challenging settings during their practicum, and as they prepared to graduate, we wondered what they now felt about teaching English in low SES schools. Using narrative inquiry, we analysed a range of reflective data to gain insight into such things as their initial motivations for entering the teaching profession and how their preconceived expectations may or may not have shifted after practicum experiences in low SES schools. We encouraged open reflection about how they perceived themselves as English teachers.

Outdoor worker sun protection project : a comprehensive applied research project to demonstrate the effectiveness of sun protection measures which influence high risk outdoor workers in Queensland to adopt sun safe behaviour practices 2010 – 2013

The QUT Outdoor Worker Sun Protection (OWSP) project undertook a comprehensive applied health promotion project to demonstrate the effectiveness of sun protection measures which influence high risk outdoor workers in Queensland to adopt sun safe behaviours. The three year project (2010-2013) was driven by two key concepts: 1) The hierarchy of control, which is used to address risks in the workplace, advocates for six control measures that need to be considered in order of priority (refer to Section 3.4.2); and 2) the Ottawa Charter which recommends five action means to achieve health promotion (refer to Section 2.1). The project framework was underpinned by a participatory action research approach that valued peoples’ input, took advantage of existing skills and resources, and stimulated innovation (refer to Section 4.2). Fourteen workplaces (small and large) with a majority outdoor workforce were recruited across regional Queensland (Darling Downs, Northwest, Mackay and Cairns) from four industries types: 1) building and construction, 2) rural and farming, 3) local government, and 4) public sector. A workplace champion was identified at each workplace and was supported (through resource provision, regular contact and site visits) over a 14 to 18 month intervention period to make sun safety a priority in their workplace. Employees and employers were independently assessed for pre- and postintervention sun protection behaviours. As part of the intervention, an individualised sun safety action plan was developed in conjunction with each workplace to guide changes across six key strategy areas including: 1) Policy (e.g., adopt sun safety practices during all company events); 2) Structural and environmental (e.g., shade on worksites; eliminate or minimise reflective surfaces); 3) Personal protective equipment (PPE) (e.g., trial different types of sunscreens, or wide-brimmed hats); 4) Education and awareness (e.g., include sun safety in inductions and toolbox talks; send reminder emails or text messages to workers);5) Role modelling (e.g., by managers, supervisors, workplace champions and mentors); and 6) Skin examinations (e.g., allow time off work for skin checks). The participatory action process revealed that there was no “one size fits all” approach to sun safety in the workplace; a comprehensive, tailored approach was fundamental. This included providing workplaces with information, resources, skills, know how, incentives and practical help. For example, workplaces engaged in farming complete differing seasonal tasks across the year and needed to prepare for optimal sun safety of their workers during less labour intensive times. In some construction workplaces, long pants were considered a trip hazard and could not be used as part of a PPE strategy. Culture change was difficult to achieve and workplace champions needed guidance on the steps to facilitate this (e.g., influencing leaders through peer support, mentoring and role modelling). With the assistance of the project team the majority of workplaces were able to successfully implement the sun safety strategies contained within their action plans, up skilling them in the evidence for sun safety, how to overcome barriers, how to negotiate with all relevant parties and assess success. The most important enablers to the implementation of a successful action plan were a pro-active workplace champion, strong employee engagement, supportive management, the use of highly visual educational resources, and external support (provided by the project team through regular contact either directly through phone calls or indirectly through emails and e-newsletters). Identified barriers included a lack of time, the multiple roles of workplace champions, (especially among smaller workplaces), competing issues leading to a lack of priority for sun safety, the culture of outdoor workers, and costs or budgeting constraints. The level of sun safety awareness, knowledge, and sun protective behaviours reported by the workers increased between pre-and post-intervention. Of the nine sun protective behaviours that were assessed, the largest changes reported included a 26% increase in workers who “usually or always” wore a broad-brimmed hat, a 20% increase in the use of natural shade, a 19% increase in workers wearing long-sleeved collared shirts, and a 16% increase in workers wearing long trousers.

Get real : the development, implementation and evaluation of an intervention for primary aged children with High Functioning Autism

Children with Autism Spectrum Disorder experience difficulty in communication and in understanding the social world which can have negative consequences for their relationships, in managing emotions, and generally dealing with the challenges of everyday life. This thesis examines the effectiveness of the Active and Reflective components of the Get REAL program through the assessment of the detailed coding of video-recorded observations and longitudinal quantitative analysis. The aim of Get REAL is to increase the social, emotional, and cognitive learning of children with High Functioning Autism (HFA). Get REAL is a group program designed specifically for use in inclusive primary school settings. The Get REAL program was designed in response to the mixed success of generalisation of learning to new contexts of existing social skills programs. The theoretical foundation of Get REAL is based upon pedagogical theory and learning theory to facilitate transfer of learning, combined with experiential, individualised, evaluative and organisational approaches. This thesis is by publication and consists of four refereed journal papers; 1 accepted for publication and 3 that are under review. Paper 1 describes the development and theoretical basis of the Get REAL program and provides detail of the program structure and learning cycle. The focus of Paper 1 reflects the first question of interest in the thesis which is about the extent to which learning derived from participation in the program can be generalised to other contexts. Participants are 16 children with HFA ranging in age from 8-13 years. Results provided support for the generalisability of learning from Get REAL to home and school evidenced by parent and teacher data collected pre and post participation in Get REAL. Following establishment of the generalisation of learning from Get REAL, Papers 2 and 3 focus on the Active and Reflective components of the program in order to examine how individual and group learning takes place. Participants (N = 12) in the program are video-taped during the Active and Reflective Sessions. Using identical coding protocols of video data, improvements in prosocial behaviour and diminishing of inappropriate behaviours were apparent with the exception of perspective taking. Data also revealed that 2 of the participants had atypical trajectories. An in-depth case study analysis was then conducted with these 2 participants in Paper 4. Data included reports from health care and education professionals within the school and externally (e.g., paediatrician) and identified the multi-faceted nature of care needed for children with comorbid diagnoses and extremely challenging family circumstances as a complex task to effect change. Results of this research support the effectiveness of the Get REAL program in promoting pro social behaviours such as improvements in engaging with others and emotional regulation, and in diminishing unwanted behaviours such as conduct problems. Further, the gains made by the participating children were found to be generalisable beyond Get REAL to home and other school settings. The research contained in the thesis adds to current knowledge about how learning can take place for children with HFA. Results show that an experiential learning framework with a focus on social cognition, together with explicit teaching, scaffolded with video feedback, are key ingredients for the generalisation of social learning to broader contexts.

Multidirectional effects of Sr, Mg and Si-containing bioceramic coatings with high bonding strength on inflammation, osteoclastogenesis and osteogenesis

Ideal coating materials for implants should be able to induce excellent osseointegration, which requires several important parameters, such as good bonding strength, limited inflammatory reaction, balanced osteoclastogenesis and osteogenesis, to gain well-functioning coated implants with long-term life span after implantation. Bioactive elements, like Sr, Mg and Si, have been found to play important roles in regulating the biological responses. It is of great interest to combine bioactive elements for developing bioactive coatings on Ti-6Al-4V orthopedic implants to elicit multidirectional effects on the osseointegration. In this study, Sr, Mg and Si-containing bioactive Sr2MgSi2O7 (SMS) ceramic coatings on Ti-6Al-4V were successfully prepared by plasma-spray coating method. The prepared SMS coatings have significantly higher bonding strength (~37MPa) than conventional pure hydroxyapatite (HA) coatings (mostly in the range of 15-25 MPa). It was also found that the prepared SMS coatings switch the macrophage phenotype into M2 extreme, inhibiting the inflammatory reaction via the inhibition of Wnt5A/Ca2+ and Toll-like receptor (TLR) pathways of macrophages. In addition, the osteoclastic activities were also inhibited by SMS coatings. The expression of osteoclastogenesis related genes (RANKL and MCSF) in bone marrow derived mesenchymal cells (BMSCs) with the involvement of macrophages was decreased, while OPG expression was enhanced on SMS coatings compared to HA coatings, indicating that SMS coatings also downregulated the osteoclastogenesis. However, the osteogenic differentiation of BMSCs with the involvement of macrophages was comparable between SMS and HA coatings. Therefore, the prepared SMS coatings showed multidirectional effects, such as improving bonding strength, reducing inflammatory reaction and downregulating osteoclastic activities, but maintaining a comparable osteogenesis, as compared with HA coatings. The combination of bioactive elements of Sr, Mg and Si into bioceramic coatings can be a promising method to develop bioactive implants with multifunctional properties for orthopaedic application.

Effect of culture conditions and calcium phosphate coating on ectopic bone formation

This study investigated the effect of a calcium phosphate (CaP) coating onto a polycaprolactone melt electrospun scaffold and in vitro culture conditions on ectopic bone formation in a subcutaneous rat model. The CaP coating resulted in an increased alkaline phosphatase activity (ALP) in ovine osteoblasts regardless of the culture conditions and this was also translated into higher levels of mineralisation. A subcutaneous implantation was performed and increasing ectopic bone formation was observed over time for the CaPcoated samples previously cultured in osteogenic media whereas the corresponding non-coated samples displayed a lag phase before bone formation occurred from 4 to 8 weeks post-implantation. Histology and immunohistochemistry revealed bone fill through the scaffolds 8 weeks post-implantation for coated and non-coated specimens and that ALP, osteocalcin and collagen 1 were present at the ossification front and in the bone tissues. Vascularisation in the vicinity of the bone tissues was also observed indicating that the newly formed bone was not deprived of oxygen and nutrients.We found that in vitro osteogenic induction was essential for achieving bone formation and CaP coating accelerated the osteogenic process. We conclude that high cell density and preservation of the collagenous and mineralised extracellular matrix secreted in vitro are factors of importance for ectopic bone formation.