5 research outputs found
Background concentrations of metals and metalloids and their relationship to minerology and grainsize distribution in Darwin Harbour sediment FINAL REPORT
This study investigated the relationships between metal/metalloid concentrations, mineralogy and grainsize distribution in order to derive natural pre-development concentrations in Darwin Harbour intertidal sediment. It also aimed to define the degree to which anthropogenic activity have enriched metal/metalloid concentrations in different parts of the harbour to help identify their sources and dispersion patterns.1. Background, rationale and aims -- 2. Darwin Harbour -- 3. Previous studies of sediment composition and movement -- 4. Methodology -- 5. Results and Discussion -- 6. Conclusions -- Acknowledgements -- References -- AppendixMade available by via Publications (Legal Deposit) Act 2004 (NT)
The isotopic signature of monsoon conditions, cloud modes, and rainfall type
This work provides a comprehensive physically based framework for the interpretation of the north Australian rainfall stable isotope record (δ18O and δ2H). Until now, interpretations mainly relied on statistical relationships between rainfall amount and isotopic values on monthly timescales. Here, we use multiseason daily rainfall stable isotope and high resolution (10âmin) groundâbased Câband polarimetric radar data and show that the five weather types (monsoon regimes) that constitute the Australian wet season each have a characteristic isotope ratio. The data suggest that this is not only due to changes in regional rainfall amount during these regimes but, more importantly, is due to different rain and cloud types that are associated with the large scale circulation regimes. Negative (positive) isotope anomalies occurred when stratiform rainfall fractions were large (small) and the horizontal extent of raining areas were largest (smallest). Intense, yet isolated, convective conditions were associated with enriched isotope values whereas more depleted isotope values were observed when convection was widespread but less intense. This means that isotopic proxy records may record the frequency of which these typical wet season regimes occur. Positive anomalies in paleoclimatic records are most likely associated with periods where continental convection dominates and convection is seaâbreeze forced. Negative anomalies may be interpreted as periods when the monsoon trough is active, convection is of the oceanic type, less electric, and stratiform areas are wide spread. This connection between variability of rainfall isotope anomalies and the intrinsic properties of convection and its largeâscale environment has important implications for all fields of research that use rainfall stable isotopes
Per- and Polyfluoroalkyl Substances(PFAS)testing in sediment and aquatic foods from Darwin Harbour
This study measured the concentrations ofthirteen Per-and Polyfluoroalkyl Substances(PFAS), including perfluorooctanoic acid (PFOA),perfluorooctane sulfonate (PFOS), and perfluorohexane sulfonate (PFHxS) in aquatic sediment and biota from creeks and coastal waters in and around Darwin, Northern Territory. The biota are used for human consumption (aquatic foods)
Author Correction: Genomic analysis of sewage from 101 countries reveals global landscape of antimicrobial resistance (Nature Communications, (2022), 13, 1, (7251), 10.1038/s41467-022-34312-7)
In this article, the author name Antoinette Ngandjio was incorrectly written as Antoinette Ngandijo. In this article, the affiliation details for Author Sara Cuadros-Orellana were incorrectly given as âCentro de Biotecnologνa de los Recursos Naturales, Facultad de Ciencias Agrarias y Forestales, Talca, Chileâ but should have been âUniversidad Catolica del Maule, Centro de BiotecnologĂa de los Recursos Naturales, Facultad de Ciencias Agrarias y Forestales, Talca, Chileâ. The original article has been corrected
Genomic analysis of sewage from 101 countries reveals global landscape of antimicrobial resistance
Antimicrobial resistance (AMR) is a major threat to global health. Understanding the emergence, evolution, and transmission of individual antibiotic resistance genes (ARGs) is essential to develop sustainable strategies combatting this threat. Here, we use metagenomic sequencing to analyse ARGs in 757 sewage samples from 243 cities in 101 countries, collected from 2016 to 2019. We find regional patterns in resistomes, and these differ between subsets corresponding to drug classes and are partly driven by taxonomic variation. The genetic environments of 49 common ARGs are highly diverse, with most common ARGs carried by multiple distinct genomic contexts globally and sometimes on plasmids. Analysis of flanking sequence revealed ARG-specific patterns of dispersal limitation and global transmission. Our data furthermore suggest certain geographies are more prone to transmission events and should receive additional attention