Hematodinium sp. infection does not drive collateral disease contraction in a crustacean host

Host, pathogen, and environment are determinants of the disease triangle, the latter being a key driver of disease outcomes and persistence within a community. The dinoflagellate genus Hematodinium is detrimental to crustaceans globally – considered to suppress the innate defences of hosts, making them more susceptible to co-infections. Evidence supporting immune suppression is largely anecdotal and sourced from diffuse accounts of compromised decapods. We used a population of shore crabs (Carcinus maenas), where Hematodinium sp. is endemic, to determine the extent of collateral infections across two distinct environments (open-water, semi-closed dock). Using a multi-resource approach (PCR, histology, haematology, population genetics, eDNA), we identified 162 Hematodinium-positive crabs and size/sex-matched these to 162 Hematodinium-free crabs out of 1191 analysed. Crabs were interrogated for known additional disease-causing agents; haplosporidians, microsporidians, mikrocytids, Vibrio spp., fungi, Sacculina, trematodes, and haemolymph bacterial loads. We found no significant differences in occurrence, severity, or composition of collateral infections between Hematodinium-positive and Hematodinium-free crabs at either site, but crucially, we recorded site-restricted blends of pathogens. We found no gross signs of host cell immune reactivity towards Hematodinium in the presence or absence of other pathogens. We contend Hematodinium sp. is not the proximal driver of co-infections in shore crabs, which suggests an evolutionary drive towards latency in this environmentally plastic host

Tracking Onslow: a community in transition. edition 3, late 2013

When change is happening, communities talk and some tales get taller in the telling. Opinions are often based on shared stories and collectively these opinions are the community sentiment that affects the way people live and act. This magazine was produced by a collaboration between the ECU Journalism Program and the Shire of Ashburton that set out to track the shifts in the community sentiment in Onslow over the construction phase of the Wheatstone and Macedon gas hubs. The project aims to capture the stories being told in Onslow as the town changes, regardless of their factual accuracy. Where possible we have sought to verify facts and provide balance, but we have not excluded comments by community members on the grounds that they didn\u27t check out, because if we did that, then this would not be an accurate record of what people are saying. In all cases we have been careful to correctly report what people said in our interviews. The result is a sometimes optimistic and sometimes disgruntled reaction to the town\u27s rapid, but in some ways not rapid enough, growth spurt. We hope that you enjoy this snapshot of what was being said in Onslow in the middle of 2013 and find it interesting food for thought about the impact of major resource projects on their host communities. There is a digital version of the magazine available on the website so you can email a link to it to your family and friends in other places. The website also has soon-to-be updated galleries showing how parts of the town have changed almost beyond recognition and video interviews with Onslow locals. We look forward to seeing you when we come back in early 2014

Tracing Onslow: a community in transition. edition 4, early 2014

This edition marks two years since this project began and we started listening to and documenting what the people of Onslow have to say about the ways the Macedon and Wheatstone Gas Hub Projects are changing their town. We come every six months to record the sentiments and write a first draft of the evolving history of the town, that we publish as a magazine in hardcopy and available online. This project is supported by the Shire of Ashburton that funds our visits to Onslow, while respecting the independence of our journalism. We receive no funding from Chevron or BHP Billiton. Despite our neutral position, we get little co-operation from Chevron which refuses to give us access to any Chevron staff or sites and went as far as blocking us from attending a CRG meeting held on February 12, 2014, at the Onslow Sports Club. In the words of community liaison officer Jeremy Coulson “You can’t come in. It’s for community members only. We ran it past our manager in Perth and he was not keen on you coming in.” We were told by community members after the meeting that several contentious issues were raised but they are clearly issues that Chevron would rather keep a lid on. It’s incidents like this that convince us that the task of telling the real story of Onslow is an important one and we are grateful to the many locals who take time to talk to us and tell us their stories and concerns. If you would like digital copies of the magazine go to www.trackingonslow.net and for hardcopies visit the shire or contact me (my details are on the next page). We’d also love to hear from you, if you have a story to tell, or concerns you’d like to put on the record. We look forward to seeing you when we’re back in Onslow in July 2014

Operando potassium K-edge X-ray absorption spectroscopy: investigating potassium catalysts during soot oxidation.

The chemical and structural nature of potassium compounds involved in catalytic soot oxidation have been studied by a combination of temperature programmed oxidation and operando potassium K-edge X-ray absorption spectroscopy experiments. These experiments are the first known operando studies using tender X-rays (∼3.6 keV) under high temperature oxidation reaction conditions. X-ray absorption near edge structure analysis of K2CO3/Al2O3 catalysts during heating shows that, at temperatures between 100 and 200 °C, potassium species undergo a structural change from an initial hydrated K2CO3·xH2O and KHCO3 mixture to well-defined K2CO3. As the catalyst is heated from 200 °C to 600 °C, a feature associated with multiple scattering shifts to lower energy, indicating increased K2CO3 dispersion, due to its mobility at high reaction temperature. This shift was noted to be greater in samples containing soot than in control experiments without soot and can be attributed to enhanced mobility of the K2CO3, due to the interaction between soot and potassium species. No potassium species except K2CO3 could be defined during reactions, which excludes a potential reaction mechanism in which carbonate ions are the active soot-oxidising species. Simulations of K-edge absorption near edge structures were performed to rationalise the observed changes seen. Findings showed that cluster size, unit cell distortions and variation in the distribution of potassium crystallographic sites influenced the simulated spectra of K2CO3. While further simulation studies are required for a more complete understanding, the current results support the hypothesis that changes in the local structure on dispersion can influence the observed spectra. Ex situ characterisation was carried out on the fresh and used catalyst, by X-ray diffraction and X-ray photoelectron spectroscopy, which indicated changes to the carbonate species, in line with the X-ray absorption spectroscopy experiments

The riparian reactive interface: a climate-sensitive gatekeeper of global nutrient cycles

Riparian zones are critical interfaces to freshwater systems, acting as gateways for the conveyance and modification of macronutrient fluxes from land to rivers and oceans. In this paper, we propose that certain riparian conditions and processes (conceptually 'Riparian Reactive Interfaces') may be susceptible to environmental change with consequences of accelerating local nutrient cycling cascading to global impacts on the cycles of carbon (C), nitrogen (N), and phosphorus (P). However, we argue that this concept is insufficiently understood and that research has not yet established robust baseline data to predict and measure change at the key riparian ecosystem interface. We suggest one contributing factor as lack of interdisciplinary study of abiotic and biotic processes linking C, N, and P dynamics and another being emphasis on riparian ecology and restoration that limits frameworks for handling and scaling topography-soil-water-climate physical and biogeochemical observations from plot to large catchment scales. Scientific effort is required now to evaluate riparian current and future controls on global nutrient cycles through multi-nutrient (and controlling element) studies, grounded in landscape frameworks for dynamic riparian behaviour variation, facilitating scaling to catchment predictions

Tracking Onslow: a community in transition. edition 5, October 2014

This is the fifth edition of Tracking Onslow and the first that is not the result of a visit to the town. In June 2014 we were told that the Shire would not be funding the flights, accommodation or printing for the edition and so the ECU crew looked for other ways to continue documenting the impact of Wheatstone and Macedon on Onslow. Fortunately, our previous visits in July 2012, February 2013, July 2013 and February 2014 had filled our contact books with names and numbers and clued us in to issues that needed to be followed up. After a phone around for updates it was clear that this is not the time to be letting go of the process of documenting the challenges facing the Onslow community. We are very grateful to teacher James Trimble and his students, Amber and Taylor, for helping with the In Your Words section. We’d also like to thank everyone who spoke to us by phone and sent us images. We heard that there were concerns expressed earlier in the year about an image of the Anzac Memorial on our last cover and we would like to clarify that we did nothing to encourage the children to climb on it. We saw them there and snapped the picture. The photo is a true representation of something that happens in Onslow, and as such we reported it. One of the key functions of journalism is operating as a ‘town square’, where the opinions of different members of the community are aired. In this way a publication can help facilitate debate and understanding between different groups. We know that not everyone in Onslow agrees with each other, but we seek to allow everyone a space to speak through our pages. Sometimes opinions are based on misunderstood facts and so some of the things people say may not be true. We can’t vouch for the truth of what the people we spoke to said, but we have faithfully recorded it so that this edition is a true record of what was being said in and about Onslow in mid-late 2014. We hope you enjoy reading it

An ensemble of structures of Burkholderia pseudomallei 2,3-bisphosphoglycerate-dependent phosphoglycerate mutase

An ensemble of crystal structures are reported for 2,3-bisphosphoglycerate-dependent phosphoglycerate mutase from B. pseudomallei. The structures include two vanadate complexes, revealing the structure of a close analogue of the transition state for phosphate transfer