Comparison of eight published static finite element models of the intact lumbar spine : predictive power of models improves when combined together

Finite element (FE) model studies have made important contributions to our understanding of functional biomechanics of the lumbar spine. However, if a model is used to answer clinical and biomechanical questions over a certain population, their inherently large inter-subject variability has to be considered. Current FE model studies, however, generally account only for a single distinct spinal geometry with one set of material properties. This raises questions concerning their predictive power, their range of results and on their agreement with in vitro and in vivo values. Eight well-established FE models of the lumbar spine (L1-5) of different research centres around the globe were subjected to pure and combined loading modes and compared to in vitro and in vivo measurements for intervertebral rotations, disc pressures and facet joint forces. Under pure moment loading, the predicted L1-5 rotations of almost all models fell within the reported in vitro ranges, and their median values differed on average by only 2° for flexion-extension, 1° for lateral bending and 5° for axial rotation. Predicted median facet joint forces and disc pressures were also in good agreement with published median in vitro values. However, the ranges of predictions were larger and exceeded those reported in vitro, especially for the facet joint forces. For all combined loading modes, except for flexion, predicted median segmental intervertebral rotations and disc pressures were in good agreement with measured in vivo values. In light of high inter-subject variability, the generalization of results of a single model to a population remains a concern. This study demonstrated that the pooled median of individual model results, similar to a probabilistic approach, can be used as an improved predictive tool in order to estimate the response of the lumbar spine.

Exploring the effect of achievements on students attending university orientation

University orientation is a key event for new students that aids in the transition from a school to a university environment. A smartphone orientation application was built to aid students attending the event. Achievements were added to the application in an attempt to engage students further with the orientation activities and application. An exploratory field study was undertaken to evaluate the effect of the achievement system on participants attending orientation. Forty-six new students were recruited to test the orientation application. Twenty-six participants used a gamified version of the orientation application and twenty participants used a non-gamified version. While the gamification was generally well received, no impact on user experience was evident. Some effect on engagement with orientation activities was shown. Participants who used the gamified system reported the game elements as fun, but some negative issues arose, such as cheating.

Acceptability-based QoE management for user-centric mobile video delivery : a field study evaluation

Effective Quality of Experience (QoE) management for mobile video delivery – to optimize overall user experience while adapting to heterogeneous use contexts – is still a big challenge to date. This paper proposes a mobile video delivery system to emphasize the use of acceptability as the main indicator of QoE to manage the end-to-end factors in delivering mobile video services. The first contribution is a novel framework for user-centric mobile video system that is based on acceptability-based QoE (A-QoE) prediction models, which were derived from comprehensive subjective studies. The second contribution is results from a field study that evaluates the user experience of the proposed system during realistic usage circumstances, addressing the impacts of perceived video quality, loading speed, interest in content, viewing locations, network bandwidth, display devices, and different video coding approaches, including region-of-interest (ROI) enhancement and center zooming

DIY media architecture: Open and participatory approaches to community engagement

Media architecture’s combination of the digital and the physical can trigger, enhance, and amplify urban experiences. In this paper, we examine how to bring about and foster more open and participatory approaches to engage communities through media architecture by identifying novel ways to put some of the creative process into the hands of laypeople. We review technical, spatial, and social aspects of DIY phenomena with a view to better understand maker cultures, communities, and practices. We synthesise our findings and ask if and how media architects as a community of practice can encourage the ‘open-sourcing’ of information and tools allowing laypeople to not only participate but become active instigators of change in their own right. We argue that enabling true DIY practices in media architecture may increase citizen control. Seeking design strategies that foster DIY approaches, we propose five areas for further work and investigation. The paper begs many questions indicating ample room for further research into DIY Media Architecture.

Including nonequilibrium interface kinetics in a continuum model for melting nanoscaled particles

The melting temperature of a nanoscaled particle is known to decrease as the curvature of the solid-melt interface increases. This relationship is most often modelled by a Gibbs--Thomson law, with the decrease in melting temperature proposed to be a product of the curvature of the solid-melt interface and the surface tension. Such a law must break down for sufficiently small particles, since the curvature becomes singular in the limit that the particle radius vanishes. Furthermore, the use of this law as a boundary condition for a Stefan-type continuum model is problematic because it leads to a physically unrealistic form of mathematical blow-up at a finite particle radius. By numerical simulation, we show that the inclusion of nonequilibrium interface kinetics in the Gibbs--Thomson law regularises the continuum model, so that the mathematical blow up is suppressed. As a result, the solution continues until complete melting, and the corresponding melting temperature remains finite for all time. The results of the adjusted model are consistent with experimental findings of abrupt melting of nanoscaled particles. This small-particle regime appears to be closely related to the problem of melting a superheated particle.

Tumor-suppressor gene promoter hypermethylation in saliva of head and neck cancer patients

Head and neck squamous cell carcinoma (HNSCC) accounts for a bulk of the oral and laryngeal cancers, the majority (70%) of which are associated with smoking and excessive drinking, major known risk factors for the development of HNSCC. In contrast to reports that suggest an inverse relationship between smoking and global DNA CpG methylation, hypermethylation of promoters of a number of genes was detected in saliva collected from patients with HNSCC. Using a sensitive methylation-specific polymerase chain reaction (MSP) assay to determine specific methylation events in the promoters of RASSF1A, DAPK1, and p16 genes, we demonstrate that we can detect tumor presence with an overall accuracy of 81% in the DNA isolated from saliva of patients with HNSCC (n = 143) when compared with the DNA isolated from the saliva of healthy nonsmoker controls (n = 31). The specificity for this MSP panel was 87% and the sensitivity was 80%(with a Fisher exact test P < .0001). In addition, the test panel performed extremely well in the detection of the early stages of HNSCCs, with a sensitivity of 94% and a specificity of 87%, and a high. concordance value of 0.8, indicating an excellent overall agreement between the presence of HNSCC and a positive MSP panel result. In conclusion, we demonstrate that the promoter methylation of RASSF1A, DAPK1, and p16 MSP panel is useful in detecting hypermethylation events in a noninvasive manner in patients with HNSCC.

A time for everything : reviewing an institution’s virtual learning environment

This paper outlines a review carried out at Queensland University of Technology (QUT) in 2013 to identify the extent to which the centrally supported virtual learning environment met current and future learning and teaching needs. A range of consultation and investigation activities occurred from May to November to encourage open stakeholder feedback as well as to allow for reflection on alternative digital technologies, systems and strategies. This resulted in the development of nine recommendations, which, following a planning phase, will commence being implemented from mid-2014.

In the right space : exploring the dynamics between design, environment and pedagogy

The environments that we inhabit shape our everyday lives, influencing our behaviors and responses (Manu, 2013). As we enter an immersive phase of education in which physical and digital environments become inseparable, should we reconsider the role and importance of design on pedagogical practice? This paper explores the reciprocal cause and effect of space, technology and pedagogy in shaping the design of educational experiences within Queensland University of Technology's collaborative learning spaces.

Gold nanospikes based microsensor as a highly accurate mercury emission monitoring system

Anthropogenic elemental mercury (Hg0) emission is a serious worldwide environmental problem due to the extreme toxicity of the heavy metal to humans, plants and wildlife. Development of an accurate and cheap microsensor based online monitoring system which can be integrated as part of Hg0 removal and control processes in industry is still a major challenge. Here, we demonstrate that forming Au nanospike structures directly onto the electrodes of a quartz crystal microbalance (QCM) using a novel electrochemical route results in a self-regenerating, highly robust, stable, sensitive and selective Hg0 vapor sensor. The data from a 127 day continuous test performed in the presence of volatile organic compounds and high humidity levels, showed that the sensor with an electrodeposted sensitive layer had 260% higher response magnitude, 3.4 times lower detection limit (,22 mg/m3 or ,2.46 ppbv) and higher accuracy (98% Vs 35%) over a Au control based QCM (unmodified) when exposed to a Hg0 vapor concentration of 10.55 mg/m3 at 1016C. Statistical analysis of the long term data showed that the nano-engineered Hg0 sorption sites on the developed Au nanospikes sensitive layer play a critical role in the enhanced sensitivity and selectivity of the developed sensor towards Hg0 vapor.

Privacy in the new era of visible and sharable energy-use information

A new era of visible and sharable electricity information is emerging. Where eco-feedback is installed, households can now visualise many aspects of their energy consumption and share this information with others through Internet platforms such as social media. Despite providing users with many affordances, eco-feedback information can make public previously private actions from within the intimate setting of the family home. This paper represents a study focussing specifically on the privacy aspects of nascent ways for viewing and sharing this new stream of personal information. It explores the nuances of privacy related to eco-feedback both within and beyond the family home. While electricity consumption information may not be considered private itself, the household practices which eco-feedback systems makes visible may be private. We show that breaches of privacy can occur in unexpected ways and have the potential to cause distress. The paper concludes with some suggestions for how to realise the benefits of sharing energy consumption information whist effectively maintaining individuals’ conceptions of adequate privacy.

Insurance and transport law : controlling insurance contract terms : Section 54 of the Insurance Contracts Act – compliance, recovery and accountability

Commonwealth legislation covering insurance contracts contains numerous provisions designed to control the operation and effect of terms in life and general insurance contracts. For example, the Life Insurance Act 1995 (Cth) contains provisions regulating the consequences attendant upon incorrect statements in proposals [1] and non-payment of premiums, [2] provides that an insurer may only exclude liability in the case of suicide if it has made express provision for such contingency in its policy, [3] and severely restricts the efficacy of conditions as to war risks. [4] The Insurance Contracts Act 1984 (Cth) is even more intrusive and has a major impact upon contractual provisions in the general insurance field. It is beyond the scope of this note to explore all of these provisions in any detail but examples of controls and constraints imposed upon the operation and effect of contractual provisions include the following. A party is precluded from relying upon a provision in a contract of insurance if such reliance would amount to a failure to act with the utmost good faith. [5] Similarly, a policy provision which requires differences or disputes arising out of the insurance to be submitted to arbitration is void, [6] unless the insurance is a genuine cover for excess of loss over and above another specified insurance. [7] Similarly clause such as conciliation clauses, [8] average clauses, [9] and unusual terms [10] are given qualified operation. [11] However the provision in the Insurance Contracts Act that has the greatest impact upon, and application to, a wide range of insurance clauses and claims is s 54. This section has already generated a significant volume of case law and is the focus of this note. In particular this note examines two recent cases. The first, Johnson v Triple C Furniture and Electrical Pty Ltd [2012] 2 Qd R 337, (hereafter the Triple C case), is a decision of the Queensland Court of Appeal; and the second, Matthew Maxwell v Highway Hauliers Pty Ltd [2013] WASCA 115, (hereafter the Highway Hauliers case), is a decision of the Court of Appeal in Western Australia. This latter decision is on appeal to the High Court of Australia. The note considers too the decision of the New South Wales Court of Appeal in Prepaid Services Pty Ltd v Atradius Credit Insurance NV [2013] NSWCA 252 (hereafter the Prepaid Services case).These cases serve to highlight the complex nature of s 54 and its application, as well as the difficulty in achieving a balance between an insurer and an insured's reasonable expectations.

Confidence measurement in the light of signal detection theory

We compare three alternative methods for eliciting retrospective confidence in the context of a simple perceptual task: the Simple Confidence Rating (a direct report on a numerical scale), the Quadratic Scoring Rule (a post-wagering procedure), and the Matching Probability (MP; a generalization of the no-loss gambling method). We systematically compare the results obtained with these three rules to the theoretical confidence levels that can be inferred from performance in the perceptual task using Signal Detection Theory (SDT). We find that the MP provides better results in that respect. We conclude that MP is particularly well suited for studies of confidence that use SDT as a theoretical framework.

Towards universal search design

For people with cognitive disabilities, technology is more often thought of as a support mechanism, rather than a source of division that may require intervention to equalize access across the cognitive spectrum. This paper presents a first attempt at formalizing the digital gap created by the generalization of search engines. This was achieved through the development of a mapping of cognitive abilities required by users to execute low- level tasks during a standard Web search task. The mapping demonstrates how critical these abilities are to successfully use search engines with an adequate level of independence. It will lead to a set of design guidelines for search engine interfaces that will allow for the engagement of users of all abilities, and also, more importantly, in search algorithms such as query suggestion and measure of relevance (i.e. ranking).

Accreditation where accreditation is due

A laboratory with fully developed and accredited quality systems is highly desirable. In some cases it is mandatory. This is evidenced by the concerns raised when certain medical testing laboratories have not maintained appropriate standards to retain their accreditation with NATA. Whether or not third party accreditation is mandated, good laboratory practice based on sustainable systems is required. Internationally accepted standard ISO/IEC 17025 provides specific guidelines for operating a laboratory that may be accredited. To what extent should a university laboratory implement this standard? Is NATA accreditation necessary? As staffing and funding reduce is it possible to maintain high standard quality systems that are in reality truly required if assurance of results is due? Accreditation may be required where accreditation is due but is credit given by the institutions for the resources required to get there or stay there? These issues are considered in relation to university and commercial laboratories and specific case points are raised from experience with NATA accreditation in the School of Civil Engineering, QUT.