An exploratory study of the potential of resurfacing articular cartilage with synthetic phospholipids

This thesis is aimed at further understanding the uppermost lipid-filled membranous layer (i.e. surface amorphous layer (SAL)) of articular cartilage and to develop a scientific framework for re-introducing lipids onto the surface of lipid-depleted articular cartilage (i.e. "resurfacing"). The outcome will potentially contribute to knowledge that will facilitate the repair of the articular surface of cartilage where degradation is limited to the loss of the lipids of the SAL only. The surface amorphous layer is of utmost importance to the effective load-spreading, lubrication, and semipermeability (which controls its fluid management, nutrient transport and waste removal) of articular cartilage in the mammalian joints. However, because this uppermost layer of cartilage is often in contact during physiological function, it is prone to wear and tear, and thus, is the site for damage initiation that can lead to the early stages of joint condition like osteoarthritis, and related conditions that cause pain and discomfort leading to low quality of life in patients. It is therefore imperative to conduct a study which offers insight into remedying this problem. It is hypothesized that restoration (resurfacing) of the surface amorphous layer can be achieved by re-introducing synthetic surface-active phospholipids (SAPL) into the joint space. This hypothesis was tested in this thesis by exposing cartilage samples whose surface lipids had been depleted to individual and mixtures of synthetic saturated and unsaturated phospholipids. The surfaces of normal, delipidized, and relipidized samples of cartilage were characterized for their structural integrity and functionality using atomic force microscope (AFM), confocal microscope (COFM), Raman spectroscopy, magnetic resonance imaging (MRI) with image processing in the MATLAB® environment and mechanical loading experiments. The results from AFM imaging, confocal microscopy, and Raman spectroscopy revealed a successful deposition of new surface layer on delipidized cartilage when incubated in synthetic phospholipids. The relipidization resulted in a significant improvement in the surface nanostructure of the artificially degraded cartilage, with the complete SAPL mixture providing better outcomes in comparison to those created with the single SAPL components (palmitoyl-oleoyl-phosphatidylcholine, POPC and dipalmitoyl-phosphatidylcholine, DPPC). MRI analysis revealed that the surface created with the complete mixture of synthetic lipids was capable of providing semipermeability to the surface layer of the treated cartilage samples relative to the normal intact surface. Furthermore, deformation energy analysis revealed that the treated samples were capable of delivering the elastic properties required for load bearing and recovery of the tissue relative to the normal intact samples, with this capability closer between the normal and the samples incubated in the complete lipid mixture. In conclusion, this thesis has established that it is possible to deposit/create a potentially viable layer on the surface of cartilage following degradation/lipid loss through incubation in synthetic lipid solutions. However, further studies will be required to advance the ideas developed in this thesis, for the development of synthetic lipid-based injections/drugs for treatment of osteoarthritis and other related joint conditions.

A poly(lactic-co-glycolic acid) knitted scaffold for tendon tissue engineering: an in vitro and in vivo study

We have designed a composite scaffold for potential use in tendon or ligament tissue engineering. The composite scaffold was made of a cellularized alginate gel that encapsulated a knitted structure. Our hypothesis was that the alginate would act as a cell carrier and deliver cells to the injury site while the knitted structure would provide mechanical strength to the composite construct. The mechanical behaviour and the degradation profile of the poly(lactic-co-glycolic acid) knitted scaffolds were evaluated. We found that our scaffolds had an elastic modulus of 750 MPa and that they lost their physical integrity within 7 weeks of in vitro incubation. Autologous rabbit mesenchymal stem cell seeded composite scaffolds were implanted in a 1-cm-long defect created in the rabbit tendon, and the biomechanical properties and the morphology of the regenerated tissues were evaluated after 13 weeks. The regenerated tendons presented higher normalized elastic modulus of (60%) when compared with naturally healed tendons (40%). The histological study showed a higher cell density and vascularization in the regenerated tendons.

On governance structures for cloud resources and assessing their effectiveness

This research suggests information technology (IT) governance structures to manage cloud computing resources. The interest in acquiring IT resources as a utility from the cloud is gaining momentum. Cloud computing resources present organizations with opportunities to manage their IT expenditure on an ongoing basis, and are providing organizations access to modern IT resources to innovate and manage their continuity. However, cloud computing resources are no silver bullet. Organizations would need to have appropriate governance structures and policies in place to manage the cloud resources. The subsequent decisions from these governance structures will ensure effective management of cloud resources. This management will facilitate a better fit of cloud resources into organizations existing processes to achieve business (process-level) and financial (firm-level) objectives. Using a triangulation approach, we suggest four possible governance structures for managing the cloud computing resources. These structures are a chief cloud officer, a cloud management committee, a cloud service facilitation centre, and a cloud relationship centre. We also propose that these governance structures would relate to organizations cloud-related business objectives directly and indirectly to cloud-related financial objectives. Perceptive field survey data from actual and prospective cloud service adopters confirmed that the suggested structures would contribute directly to cloud-related business objectives and indirectly to cloud-related financial objectives.

Controlling whole blood activation and resultant clot properties on various material surfaces : a possible therapeutic approach for enhancing bone healing

Injured bone initiates the healing process by forming a blood clot at the damaged site. However, in severe damage, synthetic bone implants are used to provide structural integrity and restore the healing process. The implant unavoidably comes into direct contact with whole blood, leading to a blood clot formation on its surface. Despite this, most research in bone tissue engineering virtually ignores the important role of a blood clot in supporting healing. Surface chemistry of a biomaterial is a crucial property in mediating blood-biomaterials interactions, and hence the formation of the resultant blood clot. Surfaces presenting mixtures of functional groups carboxyl (–COOH) and methyl (–CH3) have been shown to enhance platelet response and coagulation activation, leading to the formation of fibrin fibres. In addition, it has been shown that varying the compositions of these functional groups and the length of alkyl groups further modulate the immune complement response. In this study, we hypothesised that a biomaterial surface with mixture of –COOH/–CH3(methyl), –CH2CH3 (ethyl) or –(CH2)3CH3 (butyl) groups at different ratios would modulate blood coagulation and complement activation, and eventually tailor the structural and functional properties of the blood clot formed on the surface, which subsequently impacts new bone formation. Firstly, we synthesised a series of materials composed of acrylic acid (AA), and methyl (MMA), ethyl (EMA) or butyl methacrylates (BMA) at different ratios and coated on the inner surfaces of incubation vials. Our surface analysis showed that the amount of –COOH groups on the surface coatings was lower than the ratios of AA prepared in the materials even though the surface content of –COOH groups increased with increasing in AA ratios. It was indicated that the surface hydrophobicity increased with increasing alkyl chain length: –CH 3 > –CH2CH3 > –(CH2)3CH3, and decreased with increasing –COOH groups. No significant differences in surface hydrophobicity was found on surfaces with –CH3 and –CH2CH3 groups in the presence of –COOH groups. The material coating was as smooth as uncoated glass and without any major flaws. The average roughness of material-coated surface (3.99 ± 0.54 nm) was slightly higher than that of uncoated glass surface (2.22 ± 0.29 nm). However, no significant differences in surface average roughness was found among surfaces with the same functionalities at different –COOH ratios nor among surfaces with different alkyl groups but the same –COOH ratios. These suggested that the surface functional groups and their compositions had a combined effect on modulating surface hydrophobicity but not surface roughness. The second part of our study was to investigate the effect of surface functional groups and their compositions on blood cascade activation and structural properties of the formed clots. It was found that surfaces with –COOH/–(CH2)3CH3 induced a faster coagulation activation than those with –COOH/–CH3 and –CH2CH3, regardless of the –COOH ratios. An increase in –COOH ratios on –COOH/–CH3 and –CH2CH3 surfaces decreased the rate of activation. Moreover, all material-coated surfaces markedly reduced the complement activation compared to uncoated glass surfaces, and the pattern of complement activation was entirely similar to that of surface-induced coagulation, suggesting there is an interaction between two cascades. The clots formed on material-coated surfaces had thicker fibrin with a tighter network at the exterior when compared to uncoated glass surfaces. Compared to the clot exteriors, thicker fibrins with a loose network were found in clot interiors. Coated surfaces resulted in more rigid clots with a significantly slower fibrinolysis after 1 h of lysis when compared to uncoated glass surfaces. Significant differences in fibrinolysis after 1 h of lysis among clots on material-coated surfaces correlated well with the differences in fibrin thickness and density at clot exterior. In addition, more growth factors were released during clot formation than during clot lysis. From an intact clot, there was a correlation between the amount of PDGF-AB release and fibrin density. Highest amount of PDGF-AB was released from clots formed on surfaces with 40% –COOH/60% –CH 3 (i.e. 65MMA). During clot lysis, the release of PDGF-AB also correlated with the fibrinolytic rate while the release of TGF-â1 was influenced by the fibrin thickness. This suggested that different clot structures led to different release profiles of growth factors in clot intact and degrading stages. We further validated whether the clots formed on material-coatings provide the microenvironment for improved bone healing by using a rabbit femoral defect model. In this pilot study, the implantation of clots formed on 65MMA coatings significantly increased new bone formation with enhanced chondrogenesis, osteoblasts activity and vascularisation, but decreased inflammatory macrophage number at the defects after 4 weeks when compared to commercial bone grafts ChronOSTM â-TCP granules. Empty defects were observed when blood clot formation was inhibited. In summary, our study demonstrated that surface functional groups and their relative ratios on material coatings synergistically modulate activation of blood cascades, resultant fibrin architecture, rigidity, susceptibility to fibrinolysis as well as growth factor release of the formed clots, which ultimately alter the healing microenvironment of injured bones.

Looking behind the increase in custodial remand populations

Numbers, rates and proportions of those remanded in custody have increased significantly in recent decades across a range of jurisdictions. In Australia they have doubled since the early 1980s, such that close to one in four prisoners is currently unconvicted. Taking NSW as a case study and drawing on the recent New South Wales Law Reform Commission Report on Bail (2012), this article will identify the key drivers of this increase in NSW, predominantly a form of legislative hyperactivity involving constant changes to the Bail Act 1978 (NSW), changes which remove or restrict the presumption in favour of bail for a wide range of offences. The article will then examine some of the conceptual, cultural and practice shifts underlying the increase. These include: a shift away from a conception of bail as a procedural issue predominantly concerned with securing the attendance of the accused at trial and the integrity of the trial, to the use of bail for crime prevention purposes; the diminishing force of the presumption of innocence; the framing of a false opposition between an individual interest in liberty and a public interest in safety; a shift from determination of the individual case by reference to its own particular circumstances to determination by its classification within pre‐set legislative categories of offence types and previous convictions; a double jeopardy effect arising in relation to people with previous convictions for which they have already been punished; and an unacknowledged preventive detention effect arising from the increased emphasis on risk. Many of these conceptual shifts are apparent in the explosion in bail conditions and the KPI‐driven policing of bail conditions and consequent rise in revocations, especially in relation to juveniles. The paper will conclude with a note on the NSW Government’s response to the NSW LRC Report in the form of a Bail Bill (2013) and brief speculation as to its likely effects.

Rodent Models of Conditioned Fear: Behavioral Measures of Fear and Memory

Pavlovian fear conditioning is a robust technique for examining behavioral and cellular components of fear learning and memory. In fear conditioning, the subject learns to associate a previously neutral stimulus with an inherently noxious co-stimulus. The learned association is reflected in the subjects' behavior upon subsequent re-exposure to the previously neutral stimulus or the training environment. Using fear conditioning, investigators can obtain a large amount of data that describe multiple aspects of learning and memory. In a single test, researchers can evaluate functional integrity in fear circuitry, which is both well characterized and highly conserved across species. Additionally, the availability of sensitive and reliable automated scoring software makes fear conditioning amenable to high-throughput experimentation in the rodent model; thus, this model of learning and memory is particularly useful for pharmacological and toxicological screening. Due to the conserved nature of fear circuitry across species, data from Pavlovian fear conditioning are highly translatable to human models. We describe equipment and techniques needed to perform and analyze conditioned fear data. We provide two examples of fear conditioning experiments, one in rats and one in mice, and the types of data that can be collected in a single experiment. © 2012 Springer Science+Business Media, LLC.

What makes school leaders inspirational and how does this relate to mentoring?

Leadership comes in many forms (such as transactional, transformational, distributed) and its effectiveness can inspire others to achieve organisational goals and visions. Inspiration as an emotional event requires receptiveness and an awareness of social interdependence. When mentees are inspired by mentor role models they can extend personal attributes and practices. Similar to other leaders, inspiring mentors can motivate mentees to develop a strength of character and achieve goals in the workplace. What makes school leaders inspirational and how does this relate to mentoring? This qualitative study collects data from 25 experienced teachers, which involved written questionnaire, work samples, and audio-recorded focus group discussions. These participants indicated that inspirational school leaders were those who had: (1) organisational goals (e.g., visionary, goal driven, innovative, & motivational); (2) professional skills such as being knowledgeable, communicative, and acknowledging others’ achievements; and (3) personal attributes (e.g., integrity, active listening, respectful, enthusiastic, & approachable). This research shows how mentors and school leaders can consider the inspirational attributes and practices outlined by participants in this study to inspire teaching staff. For example, an awareness of attentive listening, motivational and visionary practices, and acknowledging individual achievements can guide school leaders and mentors to inspire others for achieving organsational goals and visions.

Disengaged and disruptive : behaviour intervention for boys from year four to year seven

Disengaged and disruptive students have been an ongoing concern for teachers for many years. Teaching is complex—complex students with complex lives and complex behaviours. How best to help these students is an ever-present question without a simple answer. Solutions need to be found. Under a positive behaviour support framework when serious, disruptive behaviour requires intervention, an individualised positive behaviour support plan (PBS plan) is developed and implemented. This multicase study (Stake, 2006) investigated how task engagement was changed for boys from year four to year seven who demonstrated serious, disruptive behaviour. The individualised PBS plan was the primary tool of behaviour intervention in each of the five cases. Using the Behaviour Support Plan Quality Evaluation Scoring Guide II (BSP-QE) (Browning- Wright, Saren & Mayer, 2003) the five PBS plans were evaluated prior to implementation and rated highly in terms of technical quality. Positive changes in student task engagement were forthcoming in all five cases. Eleven advisory visiting teachers in behaviour and eleven classroom teachers, five of whom were case-study participants, took part in this study. The classroom teachers were employed in south-east Queensland primary schools located in suburbs of economic disadvantage. All 22 participants expressed very similar perceptions of serious, disruptive behaviour emphasising the collateral impact upon the teaching and learning. Data obtained through direct observations, surveys and semi-structured interviews confirmed previous research to reveal a strong link between integrity of PBS plan implementation and student behaviour change. While classroom teachers, in the main, effectively managed the implementation of the PBS plan, social validity of goals, procedures and effects; in-class technical assistance and performance feedback were identified as three enablers to effective teacher implementation of the PBS plan. While the purpose of each PBS plan was to influence change in student behaviour, this study found that changing teacher behaviour was also instrumental in achieving positive student outcomes. Changing teacher behaviour and building capacity was facilitated by trusting, collaborative partnerships established between the Advisory Visiting Teacher-Behaviour and the classroom teacher responsible for the plan implementation. The Advisory Visiting Teacher-Behaviour provides assistance to teachers dealing with students who demonstrate ongoing, problematic behaviour. The inclusion of a teaching component as part of the implementation stage of the consultation process appeared to have considerable influence upon successful intervention. Results substantiated earlier understandings of the importance of teacher instruction highlighting the value of explicit teaching and performance feedback to the delivery of effective behaviour intervention. Conclusions drawn from this study have had a major impact upon the work of a regional team of Advisory Visiting Teachers-Behaviour. The focus of behaviour intervention has moved from being primarily upon the individual student to include a greater emphasis upon the critical role of the teacher. Procedures and processes are being re-evaluated to align with evidence-based practice and to include a collaborative consultation approach to improve teacher assistance. The framework and content of staff development and training is being created directly from the findings of this study. This practical application of the results has informed better ways of providing behaviour intervention for students demonstrating serious, disruptive behaviour. What this study has clearly shown is that when it comes to behaviour intervention, the important role of the teacher cannot be underestimated.

Would you like data with that? Library provision of financial datasets

Within the QUT Business School (QUTBS)– researchers across economics, finance and accounting depend on data driven research. They analyze historic and global financial data across a range of instruments to understand the relationships and effects between them as they respond to news and events in their region. Scholars and Higher Degree Research Students in turn seek out universities which offer these particular datasets to further their research. This involves downloading and manipulating large datasets, often with a focus on depth of detail, frequency and long tail historical data. This is stock exchange data and has potential commercial value therefore the license for access tends to be very expensive. This poster reports the following findings: •The library has a part to play in freeing up researchers from the burden of negotiating subscriptions, fundraising and managing the legal requirements around license and access. •The role of the library is to communicate the nature and potential of these complex resources across the university to disciplines as diverse as Mathematics, Health, Information Systems and Creative Industries. •Has demonstrated clear concrete support for research by QUT Library and built relationships into faculty. It has made data available to all researchers and attracted new HDRs. The aim is to reach the output threshold of research outputs to submit into FOR Code 1502 (Banking, Finance and Investment) for ERA 2015. •It is difficult to identify what subset of dataset will be obtained given somewhat vague price tiers. •The integrity of data is variable as it is limited by the way it is collected, this occasionally raises issues for researchers(Cook, Campbell, & Kelly, 2012) •Improved library understanding of the content of our products and the nature of financial based research is a necessary part of the service.

Not all dimensions of work self-efficacy are equal : understanding the role of tertiary work placements in the development of the elements of work self-efficacy

This paper examines the relationship between a final year tertiary work placement for criminology students at Griffith University in Brisbane and the development of their work self-efficacy. Using a work self-efficacy instrument developed by Professor Joe Raelin at Northeastern University in Boston, a pilot phase in 2006 and a larger study in 2007 investigated the students’ responses across seven self-efficacy factors of learning, problem-solving, teamwork, sensitivity, politics, pressure, and role expectations. Both studies utilised a pre- and post-test and comparisons between these indicated that they believed their abilities to participate constructively in their professional work contexts significantly improved as a result of their placement experience except in the areas of learning, teamwork and sensitivity. This finding will allow us to continue to refine the processes of work placements in order to ensure the integrity of this method for student learning.

Fine tuning of elasticity via crosslinking collagen-based materials to mediate mechanotransduction and stability using corona treatment

The common goal of tissue engineering is to develop substitutes that can closely mimic the structure of extracellular matrix (ECM). However, similarly important is the intensive material properties which have often been overlooked, in particular, for soft tissues that are not to bear load assumingly. The mechanostructural properties determine not only the structural stability of biomaterials but also their physiological functionality by directing cellular activity and regulating cell fate decision. The aim here is to emphasize that cells could sense intensive material properties like elasticity and reside, proliferate, migrate and differentiate accordinglyno matter if the construct is from a natural source like cartilage, skin etc. or of synthetic one. Meanwhile, the very objective of this work is to provide a tunable scheme for manipulating the elasticity of collagen-based constructs to be used to demonstrate how to engineer cell behavior and regulate mechanotransduction. Articular cartilage was chosen as it represents one of the most complex hierarchical arrangements of collagen meshwork in both connective tissues and ECM-like biomaterials. Corona discharge treatment was used to produce constructs with varying density of crosslinked collagen and stiffness accordingly. The results demonstrated that elastic modulus increased up to 33% for samples treated up to one minute as crosslink density was found to increase with exposure time. According to the thermal analysis, longer exposure to corona increased crosslink density as the denaturation enthalpy increased. However the spectroscopy results suggested that despite the stabilization of the collagen structure the integrity of the triple helical structure remained intact. The in vitro superficial culture of heterologous chondrocytes also determined that the corona treatment can modulate migration with increased focal adhesion of cells due to enhanced stiffness, without cytotoxicity effects, and providing the basis for reinforcing three-dimensional collagen-based biomaterials in order to direct cell function and mediate mechanotransduction.

Effectiveness of MED for Fault Diagnosis in Roller Bearings

Diagnostics of rolling element bearings is usually performed by means of vibration signals measured by accelerometers placed in the proximity of the bearing under investigation. The aim is to monitor the integrity of the bearing components, in order to avoid catastrophic failures, or to implement condition based maintenance strategies. In particular, the trend in this field is to combine in a single algorithm different signal-enhancement and signal-analysis techniques. Among the first ones, Minimum Entropy Deconvolution (MED) has been pointed out as a key tool able to highlight the effect of a possible damage in one of the bearing components within the vibration signal. This paper presents the application of this technique to signals collected on a simple test-rig, able to test damaged industrial roller bearings in different working conditions. The effectiveness of the technique has been tested, comparing the results of one undamaged bearing with three bearings artificially damaged in different locations, namely on the inner race, outer race and rollers. Since MED performances are dependent on the filter length, the most suitable value of this parameter is defined on the basis of both the application and measured signals. This represents an original contribution of the paper.

Social media and journalism during times of crisis

Around lunchtime on 22 February 2011, the New Zealand city of Christchurch – the country’s second largest city – was hit by a magnitude 6.3 earthquake. Built on a geological faultline, like Los Angeles and Tokyo, Christchurch is no stranger to tremors; indeed, it had experienced a magnitude 7.1 quake just months before, in September 2010, and technically, this new earthquake was no more than an aftershock of the earlier tremor. That earlier quake had caused significant structural damage, but no fatalities, but the February earthquake was different: with its epicentre located no more than ten kilometres from the Christchurch city centre, at a depth of only five kilometres, it proved considerably more destructive – and it affected buildings whose structural integrity had already been severely compromised by the September quake, in the middle of a weekday when schools and city offices would have been fully occupied. While the full death toll has yet to be determined, it is estimated at close to 200.

A pre-clinical functional assessment of an acellular scaffold intended for the treatment of hard-to-heal wounds

Dermal wound healing is a biochemical and cellular process critical to life. While the majority of the population will only ever experience successful wound healing outcomes, some 1-3 % of those aged over 65 years will experience wound healing delay or perpetuation. These hard-to-heal wounds are comprised of degraded and dysfunctional extracellular matrix, yet the integrity of this structure is critical in the processes of normal wound healing. As such, extracellular matrix replacements have been devised that can replace dysfunctional extracellular matrix in hard-to-heal wounds with the aim of restoring normal wound healing processes. Here we evaluated a novel synthetic matrix protein for its ability to act as an acellular scaffold that can replace dysfunctional extracellular matrix. In this regard the synthetic protein demonstrated an ability to rapidly adsorb to the dermal surface, permit cell attachment and facilitate the cellular functions essential to wound healing. When applied to deep partial thickness wounds in a porcine animal model the matrix protein also demonstrated the ability to reduce wound duration. These data provide evidence that the synthetic matrix protein has the ability to function as an acellular scaffold for wound healing purposes.

Objectifying the Subjective : Assessment and Feedback in Creative Arts Studio Learning and Teaching

This paper examines the Assessment and Feedback aspects of Studio Teaching as Creative Arts pedagogy. Prompted by USQ’s newly offered Bachelor of Creative Arts (BCA), the author has developed an Assessment Matrix specifically designed to satisfy a number of imperatives, including: • ‘objectifying’ the subjective aspects of creative practice as assessable coursework/research • providing the means by which accurate, detailed, personalised and confidential feedback may be provided to students individually • providing consistent, accurate, meaningful assessment records for student, lecturer, and institution • ensuring consistency, continuity, and transparency of assessment processes and records to satisfy quality audits • minimising marking and assessment time, whilst maximising assessment integrity and depth • requiring only basic level skills and knowledge of a computer application already in common use (Microsoft Excel) • adaptability to a range of creative courses ‐ across disciplines This Assessment Matrix has been in development (and trialled) since January 2009.