Elemental characterisation and detection of heavy metals in house dusts collected from sites in South-East Queensland, Australia

Knowledge of the elements present in house dusts is important in understanding potential health effects on humans. In this study, dust samples collected from 10 houses in south-east Queensland have been analysed by scanning electron microscopy and X-ray microanalysis to measure the inorganic element compositions and to investigate the form of heavy metals in the dusts. The overall analytical results were then used to discriminate between different localities using chemometric techniques. The relative amounts of elements, particularly of Si, Ca, and Fe, varied between size fractions and between different locations for the same size fraction. By analysing individual small particles, many other constituents were identified including Ti, Cr, Mn, Ni, Cu, Zn, Ba, Ag, W, Au, Hg, Pb, Bi, La and Ce. The heavy metals were mostly concentrated in small particles in the smaller size fractions, which allowed detection by particle analysis, though their average concentrations were very low.

Microstructures and strengthening mechanisms of Cu/Ni/W nanolayered composites

Cu/Ni/W nanolayered composites with individual layer thickness ranging from 5nm to 300nm were prepared by a magnetron sputtering system. Microstructures and strength of the nanolayered composites were investigated by using the nanoindentation method combined with theoretical analysis. Microstructure characterization revealed that the Cu/Ni/W composite consists of a typical Cu/Ni coherent interface and Cu/W and Ni/W incoherent interfaces. Cu/Ni/W composites have an ultrahigh strength and a large strengthening ability compared with bi-constituent Cu–X(X¼Ni, W, Au, Ag, Cr, Nb, etc.) nanolayered composites. Summarizing the present results and those reported in the literature, we systematically analyze the origin of the ultrahigh strength and its length scale dependence by taking into account the constituent layer properties, layer scales and heterogeneous layer/layer interface characteristics, including lattice and modulus mismatch as well as interface structure.

Tunable electric field enhancement and redox chemistry on TiO2 island films via covalent attachment to Ag or Au nanostructures

Abstract Ag-TiO2 and Au-TiO2 hybrid electrodes were designed by covalent attachment of TiO2 nanoparticles to Ag or Au electrodes via an organic linker. The optical and electronic properties of these systems were investigated using the cytochrome b5 (Cyt b5) domain of sulfite oxidase, exclusively attached to the TiO2 surface, as a Raman marker and model redox enzyme. Very strong SERR signals of Cyt b 5 were obtained for Ag-supported systems due to plasmonic field enhancement of Ag. Time-resolved surface-enhanced resonance Raman spectroscopic measurements yielded a remarkably fast electron transfer kinetic (k = 60 s -1) of Cyt b5 to Ag. A much lower Raman intensity was observed for Au-supported systems with undefined and slow redox behavior. We explain this phenomenon on the basis of the different potential of zero charge of the two metals that largely influence the electronic properties of the TiO2 island film. © 2013 American Chemical Society.

Mainstreaming sustainability into pre-service teacher edcuation in Australia

There is a growing interest in and support for education for sustainability in Australian schools. Australian Government schemes such as the Australian Sustainable Schools Initiative (AuSSI), along with strategies such as Educating for a Sustainable Future: A National Environmental Education Statement for Australian Schools(NEES(Australian Government and Curriculum Corporation (2005) and Living Sustainably: The Australian Government’s National Action Plan for Education for Sustainability (Australian Government 2009), recognise the need and offer support for education for sustainability in Australian schools. The number of schools that have engaged with AuSSI indicates that this interest also exists within Australian schools. Despite this, recent research indicates that pre-service teacher education institutions and programs are not doing all they can to prepare teachers for teaching education for sustainability or for working within sustainable schools. The education of school teachers plays a vital role in achieving changes in teaching and learning in schools. Indeed, the professional development of teachers in education for sustainability has been identified as ‘the priority of priorities’. Much has been written about the need to ‘reorient teacher education towards sustainability’. Teacher education is seen as a key strategy that is yet to be effectively utilised to embed education for sustainability in schools. Mainstreaming sustainability in Australian schools will not be achieved without the preparation of teachers for this task. The Mainstreaming Sustainability model piloted in this study seeks to engage a range of stakeholder organisations and key agents of change within a system to all work simultaneously to bring about a change, such as the mainstreaming of sustainability. The model is premised on the understanding that sustainability will be mainstreamed within teacher education if there is engagement with key agents of change across the wider teacher education system and if the key agents of change are ‘deeply’ involved in making the change. The model thus seeks to marry broad engagement across a system with the active participation of stakeholders within that system. Such a systemic approach is a way of bringing together diverse viewpoints to make sense of an issue and harness that shared interpretation to define boundaries, roles and relationships leading to a better defined problem that can be acted upon more effectively. Like action research, the systemic approach is also concerned with modelling change and seeking plausible solutions through collaboration between stakeholders. This is important in ensuring that outcomes are useful to the researchers/stakeholders and the system being researched as it creates partnerships and commitments to the outcomes by stakeholder participants. The study reported on here examines whether the ‘Mainstreaming Sustainability’ model might be effective as a means to mainstream sustainability in pre-service teacher education. This model, developed in an earlier study, was piloted in the Queensland teacher education system in order to examine its effectiveness in creating organisational and systemic change. The pilot project in Queensland achieved a number of outcomes. The project: • provided useful insights into the effectiveness of the Mainstreaming Sustainability model in bringing about change while also building research capacity within the system • developed capacities within the teacher education community: o developing competencies in education for sustainability o establishing more effective interactions between decision-makers and other stakeholders o establishing a community of inquiry • changed teaching and learning approaches used in participating teacher education institutions through: o curriculum and resource development o the adoption of education for sustainability teaching and learning processes o the development of institutional policies • improved networks within the teacher education system through: o identifying key agents of change within the system o developing new, and building on existing, partnerships between schools, teacher education institutions and government agencies • engaged relevant stakeholders such as government agencies and non-government organisations to understand and support the change Our findings indicate that the Mainstreaming Sustainability model is able to facilitate organisational and systemic change – over time – if: • the individuals involved have the conceptual and personal capacities needed to facilitate change, that is, to be a key agent of change • stakeholders are engaged as participants in the process of change, not simply as ‘interested parties’ • there is a good understanding of systemic change and the opportunities for leveraging change within systems. In particular, in seeking to mainstream sustainability in pre-service teacher education in Queensland it has become clear that one needs to build capacity for change within participants such as knowledge of education for sustainability, conceptual skills in systemic thinking, action research and organisational change, and leadership skills. It is also of vital importance that key agents of change – those individuals who are ‘hubs’ within a system and can leverage for change across a wide range of the system – are identified and engaged with as early as possible. Key agents of change can only be correctly identified, however, if the project leaders and known participants have clearly identified the boundary to their system as this enables the system, sub-system and environment of the system to be understood. Through mapping the system a range of key organisations and stakeholders will be identified, including government and nongovernment organisations, teacher education students, teacher education academics, and so on. On this basis, key agents of change within the system and sub-system can be identified and invited to assist in working for change. A final insight is that it is important to have time – and if necessary the funding to ‘buy time’ – in seeking to bring about system-wide change. Seeking to bring about system-wide change is an ambitious project, one that requires a great deal of effort and time. These insights provide some considerations for those seeking to utilise the Mainstreaming Sustainability model to bring about change within and across a pre-service teacher education system.

Judge George W Paul's Japanese house : a case study

In the late 1880s a pre-fabricated Japanese house was shipped from Kobe, Japan, to Brisbane, Australia, and erected in the up-market suburb of New Farm by Japanese tradesmen. This paper is developed from a broader project researching the life of G W Paul, the man who had the house built and subsequently lived in it for the remainder of his life. Paul’s motivation in importing the house represented a unique, but unfulfilled effort to develop a future, hybrid culture for Queensland. This effort took the form of a commercial venture to construct Japanese houses as desirable and climatically suitable dwellings. Against the backdrop of this ambition, this paper presents new research to elucidate and extend previous knowledge, assesses the reception of the house by its nineteenth century Brisbane audience, and considers possible reasons for the limited response which signalled the cancellation of the commercial venture.

Integrating efficient filtration and visible-light photocatalysis by loading Ag-doped zeolite Y particles on aluminia nanofiber membrane

Filtration membrane technology has already been employed to remove various organic effluents produced from the textile, paper, plastic, leather, food and mineral processing industries. To improve membrane efficiency and alleviate membrane fouling, an integrated approach is adopted that combines membrane filtration and photocatalysis technology. In this study, alumina nanofiber (AF) membranes with pore size of about 10 nm (determined by the liquid-liquid displacement method) have been synthesized through an in situ hydrothermal reaction, which permitted a large flux and achieved high selectivity. Silver nanoparticles (Ag NPs) are subsequently doped on the nanofibers of the membranes. Silver nanoparticles can strongly absorb visible light due to the surface plasmon resonance (SPR) effect, and thus induce photocatalytic degradation of organic dyes, including anionic, cationic and neutral dyes, under visible light irradiation. In this integrated system, the dyes are retained on the membrane surface, their concentration in the vicinity of the Ag NPs are high and thus can be efficiently decomposed. Meanwhile, the usual flux deterioration caused by the accumulation of the filtered dyes in the passage pores can be avoided. For example, when an aqueous solution containing methylene blue is processed using an integrated membrane, a large flux of 200 L m-2 h-1 and a stable permeating selectivity of 85% were achieved. The combined photocatalysis and filtration function leads to superior performance of the integrated membranes, which have a potential to be used for the removal of organic pollutants in drinking water.

Book review: Ford, R.C., & Peeper, W.C. 2008. Managing Destination Marketing Organizations. Orlando: ForPer Publications

This volume represents the proceedings of the 13th ENTER conference, held at Lausanne, Switzerland during 2006. The conference brought together academics and practitioners across four tracks, which were eSolutions, refereed research papers, work-in-progress papers, and a Ph.D. workshop. This proceedings contains 40 refereed papers, which is less than the 51 papers presented in 2005. However, the editors advise that the scientific committee was stricter than in previous years, to the extent that the acceptance rate was 50%. A significant change in the current proceedings is the inclusion of extended abstracts of the 23 work-in-progress presentations. The papers cover a diverse range of topics across 16 research streams. This reviewer has adopted the approach of succinctly summarising the contribution of each of the 40-refereed papers, in the order in which they appear...

Can partial coherence interferometry be used to determine retinal shape?

Purpose: To determine likely errors in estimating retinal shape using partial coherence interferometric instruments when no allowance is made for optical distortion. Method: Errors were estimated using Gullstrand’s No. 1 schematic eye and variants which included a 10 D axial myopic eye, an emmetropic eye with a gradient-index lens, and a 10.9 D accommodating eye with a gradient-index lens. Performance was simulated for two commercial instruments, the IOLMaster (Carl Zeiss Meditec) and the Lenstar LS 900 (Haag-Streit AG). The incident beam was directed towards either the centre of curvature of the anterior cornea (corneal-direction method) or the centre of the entrance pupil (pupil-direction method). Simple trigonometry was used with the corneal intercept and the incident beam angle to estimate retinal contour. Conics were fitted to the estimated contours. Results: The pupil-direction method gave estimates of retinal contour that were much too flat. The cornea-direction method gave similar results for IOLMaster and Lenstar approaches. The steepness of the retinal contour was slightly overestimated, the exact effects varying with the refractive error, gradient index and accommodation. Conclusion: These theoretical results suggest that, for field angles ≤30º, partial coherence interferometric instruments are of use in estimating retinal shape by the corneal-direction method with the assumptions of a regular retinal shape and no optical distortion. It may be possible to improve on these estimates out to larger field angles by using optical modeling to correct for distortion.

Identification of bifunctional GA and AG intrastrand crosslinks formed between cisplatin and DNA

A combination of enzymatic digestion and electrospray ionisation mass spectrometry (ESI-MS) was used to characterise bifunctional adducts in which cisplatin is bound to GA base sequences in 8mer and 16mer oligonucleotides that do not contain other, higher affinity binding sites. The extent of formation of bifunctional adducts with GA base sequences was significant, but less than that seen with similar oligonucleotides containing either AG or GG sequences.

Mutans Streptococci and Lactobacilli Colonization in Predentate Children from the Neonatal Period to Seven Months of Age

Background/Aims: The aim of this study was to investigate the colonization of mutans streptococci (MS) and lactobacilli (LB) in predentate children from the neonatal period to 7 months. Methods: A total of 957 mother-and-child pairs were recruited from birth and followed up at 7 months. The 283 children who did not have erupted teeth at the second visit were included in the study. Oral mucosal swabs were taken, and the presence of MS and LB was determined using a commercial microbiological culture kit. Results: At mean ages of 34 days and 7 months, 9 and 11% of the infants, respectively, showed the presence of MS. In contrast, LB presence increased from 24 to 47% (p < 0.0001). MS presence in the neonatal period was associated with maternal MS counts of >105 CFU/ml (p = 0.05), while LB presence was associated with natural birth (p = 0.03) and maternal LB presence (p = 0.02). At 7 months, MS presence was associated with maternal MS counts (p = 0.02) and LB counts of >105 CFU/ml (p = 0.007). Additional predictors of MS presence at 7 months were a child’s MS counts of >105 CFU/ml at the neonatal visit (p = 0.019) and nighttime bottle feeding (p = 0.024). LB presence at 7 months was associated with maternal LB (p < 0.001) and MS presence (p = 0.02). Conclusions: MS and LB can be detected by culture in the oral cavity as early as 34 days after birth. Their infection rates increase to 11 and 47%, respectively, by the time the children reach the end of the predentate stage of oral development.

Influence of pre-exsiting surface defects on the vibrational properties of Ag nanowires

Large-scale molecular dynamics simulations are performed to characterize the effects of pre-existing surface defects on the vibrational properties of Ag nanowires. It is found that the first order natural frequency of the nanowire appears insensitive to different surface defects, indicating a defect insensitivity property of the nanowire’s Young’s modulus. In the meanwhile, an increase of the quality (Q)-factor is observed due to the presence of defects. Particular, a beat phenomenon is observed for the nanowire with the presence of a surface edge defect, which is driven by a single actuation. It is concluded that different surface defects could act as an effective mean to tune the vibrational properties of nanowires. This study sheds lights on the better understanding of nanowire’s mechanical performance when surface defects are presented, which would benefit the development of nanowire-based devices.