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Low-level radioactive wastes were disposed at the Little Forest Legacy Site (LFLS) near Sydney, Australia between 1960 and 1968. According to the disposal records, 233U contributes a significant portion of the inventory of actinide activity buried in the LFLS trenches. Although the presence of 233U in environmental samples from LFLS has been previously inferred from alpha-spectrometry measurements, it has been difficult to quantify because the 233U and 234U α-peaks are superimposed. Therefore, the amounts of 233U in groundwaters, soils and vegetation from the vicinity of the LFLS were measured using accelerator mass spectrometry (AMS). The AMS results show the presence of 233U in numerous environmental samples, particularly those obtained within, and in the immediate vicinity of, the trenched area. There is evidence for dispersion of 233U in groundwater (possibly mobilised by co-disposed organic liquids), and the data also suggest other sources of 233U contamination in addition to the trench wastes. These may include leakages and spills from waste drums as well as waste burnings, which also occurred at the site. The AMS results confirm the historic information regarding disposal of 233U in the LFLS trenches. The AMS technique has been valuable to ascertain the distribution and environmental behaviour of 233U at the LFLS and the results demonstrate the applicability of AMS for evaluating contamination of 233U at other radioactive waste sites. [Display omitted] • First results for 233U contamination at a legacy radioactive waste site. • 233U data obtained by Accelerator techniques. • Unusually high levels of 233U in many samples, consistent with disposal records. • 233U concentrations decrease with distance from waste sources. [ABSTRACT FROM AUTHOR]

The uranium isotope 233 U is not usually observed in alpha spectra from environmental samples due to its low natural and fallout abundance. It may be present in samples from sites in the vicinity of nuclear operations such as reactors or fuel reprocessing facilities, radioactive waste disposal sites or sites affected by clandestine nuclear operations. On an alpha spectrum, the two most abundant alpha emissions of 233 U (4.784 MeV, 13.2%; and 4.824 MeV, 84.3%) will overlap with the 234 U doublet peak (4.722 MeV, 28.4%; and 4.775 MeV, 71.4%), if present, resulting in a combined 233+234 U multiplet. A technique for quantifying both 233 U and 234 U from alpha spectra was investigated. A series of groundwater samples were measured both by accelerator mass spectrometry (AMS) to determine 233 U/ 234 U atom and activity ratios and by alpha spectrometry in order to establish a reliable 233 U estimation technique using alpha spectra. The Genie™ 2000 Alpha Analysis and Interactive Peak Fitting (IPF) software packages were used and it was found that IPF with identification of three peaks ( 234 U minor, combined 234 U major and 233 U minor, and 233 U major) followed by interference correction on the combined peak and a weighted average activity calculation gave satisfactory agreement with the AMS data across the 233 U/ 234 U activity ratio range (0.1–20) and 233 U activity range (2–300 mBq) investigated. Correlation between the AMS 233 U and alpha spectrometry 233 U was r 2 = 0.996 (n = 10). [ABSTRACT FROM AUTHOR]

Abstract: A technique for the isolation of thorium (Th), plutonium (Pu), americium (Am), uranium (U) and strontium (Sr) isotopes from various environmental matrices has been adapted from a previously published method specific to water samples (). Separation and isolation of the various elemental fractions from a single sub-sample is possible, thereby eliminating the need for multiple analyses. The technique involves sample dissolution, concentration via calcium phosphate co-precipitation, rapid column extraction using TEVA™, TRU™ and Sr-Spec™ resin cartridges, alpha spectrometry for Th, Pu, U and Am and Cerenkov counting for Sr. Various standard reference materials were analysed and chemical yields are in the range of 70–80% for Th, Am, U and Sr and 50–60% for Pu. Sample sizes of up to 10 L for water, 5 g for dry soil and sediment and 10 g for dry vegetation and seaweed can be processed using this technique. [Copyright &y& Elsevier]

This study presents the first measurements of anthropogenic plutonium (239Pu and 240Pu) concentrations and atom ratios (240Pu/239Pu) for Tasmania, in sediment collected from Bathurst Harbour, in the Tasmanian Wilderness World Heritage Area, Australia. The weighted mean 240Pu/239Pu atom ratio measured at this site was 0.172 ± 0.007 which is consistent with published data from mainland Australia and global and Southern Hemisphere averages. The 240Pu/239Pu atom ratios ranged between 0.11 and 0.21 with the earliest recorded 240Pu/239Pu atom ratios being the lowest, suggesting an influence of low atom ratio fallout from nuclear testing in Australia. Post-moratorium fallout 240Pu/239Pu atom ratios were consistent with other records. Lead-210 (210Pb) sediment chronologies indicate sediment accumulation rates have increased since the early part of the 19th century at this location. [Display omitted] • Presents the first measurements of fallout plutonium concentrations and 240Pu/239Pu atom ratios in Tasmania, Australia. • Uses an estuarine sediment record from a World Heritage Area to reconstruct fallout from global nuclear weapons testing. • Early 240Pu/239Pu atom ratios indicate contribution of fallout from British testing in Australia. [ABSTRACT FROM AUTHOR]

Abstract: The conditions that promote best practice in the mentoring of beginning teachers in secondary schools are explored in this paper in relation to the experiential model of learning put forward by Kolb [(1984). Experiential learning: Experience as the source of learning and development. New York: Prentice-Hall]. The underpinning processes of this learning cycle include the experience, the reflection, the learning that results and (further) experimentation. We present some empirical research from a two-year funded project on The Professional Development of Subject Induction Tutors and data derived from questionnaires completed by beginning teachers in three education authorities at the start and end of induction year and from semi-structured interviews with sub-samples of beginning teachers. The questionnaire data allowed us to distinguish three broad teacher ‘types’ in terms of their experiences of induction and the associated mentoring. In relation to these types we explored differences and similarities in the extent to which mentoring functions are distributed in schools, the extent to which different mentoring relationships allow beginning teachers to be empowered in their work, and the particular uses made of review and target setting and the value placed on these processes by beginning teachers and their mentors. Overall we found that best practice for ‘developmental mentoring’ involves elements of challenge and risk-taking within supportive school environments with clear induction systems in place and strong school ethos in relation to professional development. [Copyright &y& Elsevier]

Studies the role of Escherichia coli MobB protein in molybdenum cofactor biosynthesis. Sequence and structure of MobB; Protein-protein complexes of MobB; Structural homologues of MobB.

A comparison of chemical and chemo-enzymatic syntheses of α-2,3-sialylated octyl lactoside is reported. The chemical approach, starting from lactose and sialic acid, required 14 steps and proceeded in 5% overall yield; poor α-selectivity in the sialylation step necessitated a difficult and low yielding separation of anomers. A chemoenzymatic approach, employing recombinant Trypanosoma cruzi trans-sialidase to effect the key sialylation reaction, required 10 steps and gave a similar overall yield. Whereas the chemo-enzymatic synthesis required only three chromatographic purification steps overall, the chemical synthesis required at least nine. [Copyright &y& Elsevier]

Usage-based pricing has gained significant traction in recent times with respect to addressing transport challenges. Since such pricing is still in its infancy, at least in the context of urban transport, it is important to understand its implications and, to be specific, any potential equity issues. Based on a hypothetical usage-based pricing scheme together with 2009–2012 Household Travel Survey data of commuters residing in South East Queensland (SEQ), Australia, the results indicate that usage-based road pricing will lead to both horizontal and vertical inequity for some commuters. Most importantly, a greater percentage of these commuters are already transport and socio-economically disadvantaged. They will have no choice but to compromise their quality of life and bear addition financial burdens in the absence of feasible travel alternatives. To ensure that these social costs do not outweigh the benefits, improving the quality of urban transport systems and its integration with urban form and land use, will be required. Until this is achieved, policy makers should incorporate some form of spatial and/or temporal variability within usage-based road pricing in the studied, and similar, urban contexts. [ABSTRACT FROM AUTHOR]

Abstract The distribution of uranium isotopes (238U and 234U) in groundwaters of the south-western margin of the Great Artesian Basin (GAB), Australia, and underlying Arckaringa Basin were examined using groundwater samples and a sequential extraction of aquifer sediments. Rock weathering, the geochemical environment and α-recoil of daughter products control the 238U and 234U isotope distributions giving rise to large spatial variations. Generally, the shallowest aquifer (J aquifer) contains groundwater with higher 238U activity concentrations and 234U/238U activity ratios close to secular equilibrium. However, the source input of uranium is spatially variable as intermittent recharge from ephemeral rivers passes through rocks that have already undergone extensive weathering and contain low 238U activity concentrations. Other locations in the J aquifer that receive little or no recharge contain higher 238U activity concentrations because uranium from localised uranium-rich rocks have been leached into solution and the geochemical environment allows the uranium to be kept in solution. The geochemical conditions of the deeper aquifers generally result in lower 238U activity concentrations in the groundwater accompanied by higher 234U/238U activity ratios. The sequential extraction of aquifer sediments showed that α-recoil of 234U from the solid mineral phases into the groundwater, rather than dissolution of, or exchange with the groundwater accessible minerals in the aquifer, caused enrichment of groundwater 234U/238U activity ratios in the Boorthanna Formation. Decay of 238U in uranium-rich coatings on J aquifer sediments caused resistant phase 234U/238U activity ratio enrichment. The groundwater 234U/238U activity ratio is dependent on groundwater residence time or flow rate, depending on the flow path trajectory. Thus, uranium isotope variations confirmed earlier groundwater flow interpretations based on other tracers; however, spatial heterogeneity, and the lack of clear regional correlations, made it difficult to identify recharge and inter-aquifer leakage. Highlights • Geochemistry, weathering, and α-recoil control uranium isotope distributions. • Uranium isotope distributions were used to identify groundwater flow processes. • Sequential extractions confirm α-recoil causes disequilibrium of uranium isotopes. [ABSTRACT FROM AUTHOR]

This study aimed to identify the therapeutic benefits of utilizing the art museum, in art therapy programs, with older adults. Eight older adults participated in docent tours with an art making component at the [BLINDED FOR REVIEW] Museum in California. This study explored the phenomenological perspective of the older adults visiting the museum and aimed to understand how the experience may have impacted their well-being and sense of social support. Participant’s art, journals, and researcher’s observations were analyzed along with measures of psychological well-being, social connectedness and support. Emergent themes in the art and writing were aligned with De Botton and Armstrong’s (2013) seven functions of art. Results indicated the opportunity to explore emotions, thoughts, and memories safely within a group increased participant’s well-being and allowed for social connections. Furthermore, the art created reflected the seven functions of art, suggesting these may be useful for the layperson when visiting museums. This study supports previous research, recommending museum visits and art therapy with older adults. [ABSTRACT FROM AUTHOR]

Abstract: Changes in facial blood flow were investigated during an introductory conversation, delivering a speech, and listening to the speech afterwards in 16 people with a fear of blushing and 16 controls. It was hypothesized that fear of blushing would be associated with high ratings of self-reported blushing intensity and embarrassment during the tasks, and with persistence of the blushing reaction between tasks. Embarrassment and self-reported blushing intensity were greater in the fear-of-blushing group than in controls throughout the experiment. Increases in facial blood flow were similar in the two groups during each of the tasks. However, blushing dissipated more slowly after each task in the fear-of-blushing group than in controls, resulting in an incremental increase in facial blood flow over the course of the experiment. The slow recovery after an episode of blushing might result in physiological or social cues that help to maintain a fear of blushing. [Copyright &y& Elsevier]

Abstract This study investigated metal contamination from historical mining in lakes in the Tasmanian Wilderness World Heritage Area (TWWHA) and surrounding region. The largest increase in sedimentation and metal contamination occurred ca. 1930 when open-cut mining commenced and new mining technology was introduced into the region. The geochemical signal of lake sediments changed from reflecting the underlying geology and lithology to that reflecting mining activities. The HYSPLIT air particle trajectory model explains metal distribution in the lakes, with those in the northwest region closest to the mines having the highest metal contamination. Lake metal concentrations since mining activities commenced are in the order: Owen Tarn > Basin Lake > Perched Lake > Lake Dove > Lake Dobson > Lake Cygnus, with Perched Lake and Lakes Dove, Dobson and Cygnus in the TWWHA. Metal contamination affected centres up to 130 km down-wind of mining sites. Enrichment factors (EF) for Pb, Cu, As and Cd are >1 for all lakes, with Owen Tarn and Basin Lake having very high EFs for Cu and Pb (98 and 91, respectively). Pb, Cu, As and Cd concentrations are above the Australia/New Zealand lower sediment guidelines, with Pb, Cu and As above the high guidelines in Owen Tarn and Basin Lake. This study demonstrated the legacy of metal contamination in the TWWHA by mining activities and the consequences of a lack of execution of environmental regulations by past governments in Tasmania. Graphical abstract Unlabelled Image Highlights • Airborne metal contamination from historical mining was investigated in Tasmania. • The largest contamination occurred ca. 1930 when open-cut mining commenced. • The HYSPLIT model explains the atmospheric distribution of metal in the environment. • The metal contamination hotspot is in the northwest region of the World Heritage Area. • Cu and Pb enrichment factors are among the highest reported worldwide. [ABSTRACT FROM AUTHOR]

CuI is a candidate wasteform for the immobilization of the fission product 129 I. CuI can be made simply by the addition of CuCl to an I − bearing solution such that exchange of Cl − with I − takes place. The CuI material can then be consolidated into a wasteform by sintering at approximately 550 °C in argon or by hot isostatically pressing at 550 °C with 100 MPa of pressure. A waste loading of greater than 60 wt.% is achievable with good water leach resistance, in keeping with the low solubility product of CuI. However, like the well known wasteform candidate AgI, CuI decomposes in water containing metallic Fe. To compensate this deficiency, the sintered CuI wasteform can be further protected by surrounding it by Sn powder and HIPing at the low temperature of 200 °C. [ABSTRACT FROM AUTHOR]

The National Health and Medical Research Council and Natural Resource Management Ministerial Council of Australia developed the current Australian Drinking Water Guidelines which recommend an annual radiation dose value of 1 mSv year −1 . One of the potential major contributors to the radiation dose from drinking water is radium-228, a naturally occurring radionuclide arising from the thorium decay series. Various methods of analysing for radium-228 in water have been established and adapted by analytical radiochemistry laboratories. Seven laboratories in Australia participated in analysing radium-228 spiked water samples with activity concentrations ranging from 6 mBq L −1 to 20 Bq L −1 . The aim of the exercise was to compare and evaluate radium-228 results reported by the participating laboratories, the methods used and the detection limits. This paper presents the outcome of the exercise. [ABSTRACT FROM AUTHOR]

At many legacy radioactive waste sites, organic compounds have been co-disposed, which may be a factor in mobilisation of radionuclides at these sites. Tri-butyl phosphate (TBP) is a component of waste streams from the nuclear fuel cycle, where it has been used in separating actinides during processing of nuclear fuels. Analyses of ground waters from the Little Forest Legacy Site (LFLS) in eastern Australia were undertaken using solid-phase extraction (SPE) followed by gas chromatographic mass spectrometry (GCMS). The results indicate the presence of TBP several decades after waste disposal, with TBP only being detected in the immediate vicinity of the main disposal area. TBP is generally considered to degrade in the environment relatively rapidly. Therefore, it is likely that its presence is due to relatively recent releases of TBP, possibly stemming from leakage due to container degradation. The ongoing presence and solubility of TBP has the potential to provide a mechanism for nuclide mobilisation, with implications for long term management of LFLS and similar legacy waste sites. [ABSTRACT FROM AUTHOR]

Competition for nutrients between plants and microbes is an important determinant for plant growth, biodiversity and carbon cycling. Perturbations such as drought affect the availability of nitrogen (N) and phosphorus (P), and may cause shifts in uptake of N and P between plants and microbes. Competitiveness for these nutrients may depend on how flexible plants and microbes are in taking up N and P. We used a novel dual isotope labelling technique (15N and 32P) to assess short-term uptake of N and P by plants and microbes affected by drought in two different plant-soil systems. Mesocosms were extracted from two grassland sites differing in soil nutrient availability and plant species. Half of the mesocosms were subjected to drought one week prior to injection of 15N (as KNO3) and 32P (as H3PO4) tracers. Uptake rates of NO3− and P in plants and microbes were estimated based on average source pool enrichment during the labelling period and on plant and microbial recovery of 15N and 32P measured after 4 days of labelling. Overall competition for N and P was reduced with drought as less NO3− and P was taken up in plants and microbes. However, plant uptake of NO3− was more sensitive to drought than microbial NO3− uptake, while microbial P uptake was more sensitive than plant P uptake. These different sensitivities to drought by plants and microbes may decouple the N and P cycle with increased drought conditions. [ABSTRACT FROM AUTHOR]

Abstract: Over the last decade there has been a deliberate focus on the application of paleolimnological research to address issues of sediment flux and water quality change in the wetlands of the Murray–Darling Basin of Australia. This paper reports on the research outcomes on cores collected from sixteen wetlands along the Murrumbidgee–Murray River continuum. In all sixteen wetlands radiometric techniques and exotic pollen biomarkers were used to establish sedimentation rates from the collected cores. Fossil diatom assemblages were used to identify water source and quality changes to the wetlands. The sedimentation rates of all wetlands accelerated after European settlement, as little as two-fold, and as much as eighty times the mean rate through the Late Holocene. Some wetlands completely infilled through the Holocene, while others have rapidly progressed towards a terrestrial state due to accelerated accretion rates. Increasing wetland salinity and turbidity commenced within decades of settlement, contributing to sediment inputs. The sedimentation rate was observed to slow after river regulation in one wetland, but has accelerated recently in others. The complex history of flooding and drying, and wetland salinisation and eutrophication, influence the reliability of models used to establish recent, fine-resolution chronologies with confidence and the capacity to attribute causes to documented effects. [Copyright &y& Elsevier]

Abstract: Environmental radionuclides can be employed as tracers of sediment movement and delivery to water bodies such as lakes and reservoirs. The chronologies of sediments that have accumulated in the Cordeaux reservoir in Sydney, Australia, were determined by the rate of change of 210Pbex with depth and indicate slow accretion in the reservoir. The ratio of enrichment of radionuclides in sediment cores to 210Pbex and 137Cs concentrations in a reference soil sample within the Cordeaux catchment indicates that the dominant source of sediment in the Cordeaux reservoir is surface erosion (detachment and removal of sediment at depths less than 30cm). However, in the Kembla Creek arm of the reservoir a mixture of sources was detected and includes sheet and rill erosion together with sub-soil contributions. Implications for the utility of these radionuclide sedimentation assessments, especially where samples are limited, are that well-constrained chronologies and sources of soil erosion are facilitated. [Copyright &y& Elsevier]

Between May 2000 and February 2001, a major bloom of the toxic dinoflagellate Gymnodinium catenatum (a causative organism of Paralytic Shellfish Poisoning, PSP) affected over 1500 km of coastline of New Zealand’s North Island. As this was the first record of this species in New Zealand, we aimed to resolve whether this represented a recent introduction/spreading event or perhaps an indigenous cryptic species stimulated by environmental/climatic change. To answer this question, we analysed for G. catenatum resting cysts in 210Pb dated sediment cores (18–34 cm long; sedimentation rates 0.34–0.69 cm per year) collected by SCUBA divers from Manukau Harbour, where the species was first detected, and from Hokianga Harbour, where the highest shellfish toxicity was recorded, while using Wellington Harbour as a well-monitored control site. The results of this study conclusively demonstrate that abundant G. catenatum has been in northern New Zealand at least since the early 1980s, increasing up to 1200 cysts/g around the year 2000, but with low cyst concentrations possibly present since at least 1937. In contrast, Wellington Harbour cores contained only very sparse G. catenatum cysts (8 cysts/g), present only to a depth of 7 cm (surface mixed layer depth), reflecting an apparent recent range expansion of this dinoflagellate in New Zealand, possibly stimulated by unusual climatic conditions associated with the 2000 La Nina event. The significant increases since the early 1980s also of Protoperidinium cysts at Hokianga Harbour and of Gonyaulax, Protoperidinium and Protoceratium cysts at Manukau Harbour suggest a broad scale environmental change has occurred in Northland, New Zealand. [Copyright &y& Elsevier]