A population-based study of the effect of the HFE C282Y and H63D mutations on iron metabolism

The C282Y and H63D mutations in the HFE gene are important causes of hemochromatosis. In the elderly, these mutations might be associated with increased morbidity because of the lifelong accumulation of iron. In a population-based sample of the elderly, we determined the value of genotyping for HFE mutations to screen for subclinical hemochromatosis. HFE genotype frequencies were determined in a random group of 2095 subjects (55 years and over). In this random group, we selected within the six genotype groups a total of 342 individuals and measured their serum transferrin saturation, iron and ferritin levels. We also estimated the heritability and parameters needed to evaluate screening, including the sensitivity, specificity, positive and negative predictive values (PPV, NPV) of HFE genotypes. Iron parameters were significantly increased in subjects homozygous, heterozygous or compound heterozygous. The effect of the mutations was more pronounced in men than in women. For the H63D mutation, an allele dose effect was observed. The HFE gene explained about 5% of the variability in serum iron indices. The PPV for hemochromatosis for the C282Y homozygous was 100% in men and 67% in women. The NPV of the wild-type allele was 97% for both men and women. The sensitivity of both mutations was 70% for men and 52% for women and the specificity was 62% for men and 64% for women. Our study shows that the HFE C282Y and H63D are determinants of iron parameters in the elderly and will be effective in detecting individuals at high risk of hemochromatosis. However, when screening based on these two mutations, some individuals with subclinical hemochromatosis will be missed.

Changing the nature of teachers' work : an enquiry into the relationship between capital, the state and education

Examines the extent to which education has become a focus for capitalist intervention resulting in the restructuring of schools. Teachers were interviewed to identify changes in their work. The theories used to explain these changes are based on a Marxist approach. The thesis examines the ways in which the work of schools is constructed, arguing that the intellectual potential and creativity of both teachers and students is constrained by an education system that is constructed to meet the productive and reproductive needs of capital.

Evaluation of an internet-based psychological intervention for the treatment of erectile dysfunction

Recent research on the treatment of erectile dysfunction (ED) has focused on medical interventions, in particular oral medications. The current study examined the effectiveness of an internet-based psychological intervention for this condition. In total, 31 men (12 in treatment group, 19 in control group) completed the program. The results demonstrated that men who completed the program reported improved erectile functioning and sexual relationship satisfaction and quality. The implications of these findings for the treatment of ED are discussed.

Minimizing the limitations of GL analyser of fusion based email classification

In the last decade, the Internet email has become one of the primary method of communication used by everyone for the exchange of ideas and information. However, in recent years, along with the rapid growth of the Internet and email, there has been a dramatic growth in spam. Classifications algorithms have been successfully used to filter spam, but with a certain amount of false positive trade-offs. This problem is mainly caused by the dynamic nature of spam content, spam delivery strategies, as well as the diversification of the classification algorithms. This paper presents an approach of email classification to overcome the burden of analyzing technique of GL (grey list) analyser as further refinements of our previous multi-classifier based email classification [10]. In this approach, we introduce a “majority voting grey list (MVGL)” analyzing technique with two different variations which will analyze only the product of GL emails. Our empirical evidence proofs the improvements of this approach, in terms of complexity and cost, compared to existing GL analyser. This approach also overcomes the limitation of human interaction of existing analyzing technique.

Differences in networking activities among Australasian entrepreneurs : challenging the universal nature of entrepreneurial networking

By investigating differences in structural diversity in social networks among entrepreneurs in the Australasian area, this paper contributes to the debate on whether there is universality in the process of entrepreneurial networking. Four hypotheses were developed based on previous research. Representative samples of entrepreneurs were identified in the same manner in eight countries, from 2000 to 2004, given a total of63,350 respondents. The sampling methodologies and the questions asked were similar across all eight countries. Logistic regression was used to test for significant regional interaction effects involving business stage and structural diversity. The empirical results confirm previous indications of cultural differences in the networking practice adopted by entrepreneurs. Results are contrary to the existence of any mono-dimensional form of networking practice but do support the existence of both variform universality (culture moderates the importance of networking) and functional universality (cultural similarities in networking practice exist).

Novel high salt content polymer electrolytes based on high Tg polymers

Conductivities greater than or equal to 10⁻⁸ S cm⁻¹ at T_g are reported in polymer electrolytes based on lithium triflate salt and a series of polymers whose T_g is greater than 90°C. The highest conductivities were observed for poly(acrylonitrile) based systems with salt concentrations greater than 60 wt.%. The conductivity in all cases investigated increases with increasing salt concentration. ¹H-NMR T₂ relaxation measurements suggest that T_g decreases with increasing salt content and confirms that these materials are glassy at room temperature and hence that the conductivity is significantly decoupled from the structural relaxations. It appears that the nature of the polymer is important in determining the level of ionic conductivity, possibly due to differences in polymer coordinating ability or differences in T_g. Polymer-in-salt mixtures based on a tetra-alkyl ammonium imide molten salt and several high T_g polymers are also reported. The conductivities of these mixtures appear to be independent of the polymer type.

New insights into the fundamental chemical nature of ionic liquid film formation on magnesium alloy surfaces

Ionic liquids (ILs) based on trihexyltetradecylphosphonium coupled with either diphenylphosphate or bis(trifluoromethanesulfonyl)amide have been shown to react with magnesium alloy surfaces, leading to the formation a surface film that can improve the corrosion resistance of the alloy. The morphology and microstructure of the magnesium surface seems critical in determining the nature of the interphase, with grain boundary phases and intermetallics within the grain, rich in zirconium and zinc, showing almost no interaction with the IL and thereby resulting in a heterogeneous surface film. This has been explained, on the basis of solid-state NMR evidence, as being due to the extremely low reactivity of the native oxide films on the intermetallics (ZrO₂ and ZnO) with the IL as compared with the magnesium-rich matrix where a magnesium hydroxide and/or carbonate inorganic surface is likely. Solid-state NMR characterization of the ZE41 alloy surface treated with the IL based on (Tf)₂N− indicates that this anion reacts to form a metal fluoride rich surface in addition to an organic component. The diphenylphosphate anion also seems to undergo an additional chemical process on the metal surface, indicating that film formation on the metal is not a simple chemical interaction between the components of the IL and the substrate but may involve electrochemical processes.

Synthesis and physical property characterisation of phosphonium ionic liquids based on P(O)2(OR)2− and P(O)2(R)2− anions with potential application for corrosion mitigation of magnesium alloys

Phosphonium cation based ionic liquids (ILs) have become of interest due to their unique chemical and electrochemical stability as well as their promising tribological properties. At the same time, interest has also grown in the use of phosphate and phosphinate based ionic liquids for corrosion protection of reactive metals. In this work we describe the synthesis and characterization of six novel ionic liquids based on the tetraalkylphosponium cation coupled with organophosphate and organophosphinate anions and their sulfur analogues. The conductivity and viscosity of these ILs has been measured and discussed in terms of the nature of the interactions, effect of anion basicity and the extent of ionic character. The reaction of the IL with a ZE41 magnesium aerospace alloy surface is also demonstrated.

From profiles to rich tasks : the situated nature of 'authenticity' in the context of reforming curriculum and assessment practices

Outcome based education that has dominated Australian education in the 1990s is under review in the early years of the twenty first century. The available historical 'texts' produced during the first half of the 1990s, which include the national Statements and Profiles, and the state Curriculum and Standards Frameworks, provide us with documents that we can engage with not simply for 'history's sake', but with an opportunity to, in the words of the feminist author Dorothy Smith, 'displace[s] the analysis from the text as originating in writer or thinker, to the discourse itself as an ongoing intertextual process' bringing into view the social relations in which texts are embedded and which they organise' (1990, p. 161-2). Most Australian states and territories have now commenced significant situated, local curriculum renewal and reform. This renewed interest in curriculum offers insights into the character of recent assessment practices in Australia, recognising the tensions inherent in assessment practices and authentic assessment models. This paper explores, by way of an overview of the broad curriculum and assessment practices adopted in Australia over the past twenty-five years, the situated nature of 'authenticity' in the context of curriculum and assessment practices and how as teacher educators we are responding through our everyday work.

A simulation-based control interface layer for a high-fidelity anthropomorphic training simulator

Deakin University’s futuristic Universal Motion simulator will overcome the limitations of current motion simulator platforms by employing an anthropomorphic robot arm to provide the motion fidelity necessary to exploit the potential of modern simulation environments. Full motion simulators frequently utilize Stewart platforms to mimic the movement of vehicles during simulation. However, due to the limited motion range and dexterity of such systems, and their inability to convey realistic accelerations, they are unable to represent accurate motion characteristics. The Universal Motion Simulation aims to close the gap between the limitations of the current motion technology and real world, by introducing a flexible, modular, high-fidelity motion system that can be used for a variety of immersive training applications. The modular nature of the design allows interchangeable and configurable simulation pods to be attached to the end effectors.

Making connections with nature : bridging the theory-practice gap in outdoor and environmental education

In this paper I describe my experience in attempting to assist tertiary students connect with the natural environment through outdoor and environmental education experiences. The paper addresses research conducted with students undertaking an outdoor and environmental education degree and focuses on the pedagogical methods employed in this context. I argue that outdoor and environmental education practitioners may benefit from moving away from a mode of teaching based upon 'generic' methods and look instead to a more local, specific and contextual form of education. By describing an outdoor and environmental education journey in a local, 'ordinary' place and students' experiences in unearthing the stories embedded in this place, I aim to provide some practical strategies to engage young people in a direct and meaningful way. The intention is to broaden the pedagogical possibilities related to facilitating experiences in natural environments and thus contribute to bridging the rhetoric/reality gap in outdoor education.

Extraction of silver(i) from aqueous solutions in the absence and presence of copper(ii) with a methimazole-based ionic liquid

The ionic liquid (IL) 2-butylthiolonium bis(trifluoromethanesulfonyl)amide, [mimSBu][NTf₂], facilitates the efficient extraction of silver(i) from aqueous media via interaction with both the cation and anion components of the IL. Studies with a conventional aqueous-IL two phase system as well as microextraction of silver(i) by a thick IL film adhered to an electrode monitored in situ by cyclic voltammetry, established that [mimSBu][NTf₂] can extract electroactive silver(i) ions from an aqueous solution. The pH of the aqueous phase decreases upon addition of [mimSBu]⁺, which is attributed to partial release of the hydrogen attached to the N(3) nitrogen atom of the imidazolium ring. The presence of silver(i) further increase the acidity of the aqueous phase as a consequence of coordination with the IL cation component. Voltammetric and ¹H and ¹³C NMR techniques have been used to establish the nature of the silver(i) complexes extracted, and show that the form of interaction with the IL differs from that outlined previously for the extraction of copper(ii). Insights on the competition established when silver(i) is extracted in the presence of copper(ii) are provided. Finally, it is noted that metallic silver can be directly electrodeposited at the electrode surface after extraction of silver(i) into [mimSBu][NTf₂] and that back extraction of silver(i) into aqueous media is achieved by addition of an acidic aqueous solution.

The hidden permutation model and location-based activity recognition

Permutation modeling is challenging because of the combinatorial nature of the problem. However, such modeling is often required in many real-world applications, including activity recognition where subactivities are often permuted and partially ordered. This paper introduces a novel Hidden Permutation Model (HPM) that can learn the partial ordering constraints in permuted state sequences. The HPM is parameterized as an exponential family distribution and is flexible so that it can encode constraints via different feature functions. A chain-flipping Metropolis-Hastings Markov chain Monte Carlo (MCMC) is employed for inference to overcome the O(n!) complexity. Gradient-based maximum likelihood parameter learning is presented for two cases when the permutation is known and when it is hidden. The HPM is evaluated using both simulated and real data from a location-based activity recognition domain. Experimental results indicate that the HPM performs far better than other baseline models, including the naive Bayes classifier, the HMM classifier, and Kirshner's multinomial permutation model. Our presented HPM is generic and can potentially be utilized in any problem where the modeling of permuted states from noisy data is needed.

Dynamic shot suggestion filtering for home video based on user performance

This paper presents novel additions to our existing amateur media creation framework. The framework provides at-capture guidance to enable the home movie maker to realize their aesthetic and narrative goals and automation of post-production editing. A common problem with the amateur filming context is its contingent nature, which often results in the failure to gain footage vital to the user's goals, even with at-capture software embedding. Accordingly, we have modelled minimizing the difference between target and captured footage at a given time during filming as a probability distribution divergence problem. We apply two policies of feedback to the user on their performance, passive communication via a suggestion desirability measure, and active filtering of undesirable suggestions. We demonstrate the framework using each policy with a simulation of various user and filming situations with promising results.