An education and training programme for radiological institutes: impact on the reduction of the CT radiation dose

Objectives: To establish an education and training programme for the reduction of CT radiation doses and to assess this programme's efficacy. Methods: Ten radiological institutes were counselled. The optimisation programme included a small group workshop and a lecture on radiation dose reduction strategies. The radiation dose used for five CT protocols (paranasal sinuses, brain, chest, pulmonary angiography and abdomen) was assessed using the dose-length product (DLP) before and after the optimisation programme. The mean DLP values were compared with national diagnostic reference levels (DRLs). Results: The average reduction of the DLP after optimisation was 37% for the sinuses (180 vs. 113mGycm, P < 0.001), 9% for the brain (982 vs. 896mGycm, P < 0.05), 24% for the chest (425 vs. 322mGycm, P < 0.05) and 42% for the pulmonary arteries (352 vs. 203mGycm, P < 0.001). No significant change in DLP was found for abdominal CT. The post-optimisation DLP values of the sinuses, brain, chest, pulmonary arteries and abdomen were 68%, 10%, 20%, 55% and 15% below the DRL, respectively. Conclusions: The education and training programme for radiological institutes is effective in achieving a substantial reduction in CT radiation dos

Experiments with oenological methods to increase the spicy aroma in Austrian Grüner Veltliner wines

Grüner Veltliner is Austria's most important grape variety, accounting for 32.5% of the vineyard area (a total of around 14,500 ha). There is a noticeable trend with this variety away from fresh, fruity wines towards more spicy, single-vineyard wines. This is especially true for export-oriented producers. The aim of this scientific study is to test oenological methods for increasing the leading substance of the spicy aroma, the sesquiterpene rotundone and to sensory evaluate the wines. The methods skin contact, full and partial fermentation on the skins, addition of whole grapes and or leaves were tested in two independent experimental designs. The wines were analysed using a SPE-SPME-GC-TQMS method. The "retro-tratitional methods" of winemaking mentioned in the article can enhance the spiciness of the wines to a certain degree. Especially the addition of whole grapes as well as partial maceration gave the best results here. The increase in spiciness was observed both sensorially and analytically, as evidenced by higher rotundone contents. However, in summary, it must be stated that the results indicate that an exclusive analysis of rotundone, without the inclusion of phenols and other volatile substances, cannot contribute to a full understanding of the matter, which is based on the interaction of many components. Further analysis both sensory and analytical involving many volatile compounds and phenols are therefore absolutely necessary

Meeting Minutes for October 13, 2016

Raw DICOM image files of CT-scanned termite mound Tp

Multiple energy sources and metabolic strategies sustain microbial diversity in Antarctic desert soils

Numerous diverse microorganisms reside in the cold desert soils of continental Antarctica, though we lack a holistic understanding of the metabolic processes that sustain them. Here, we profile the composition, capabilities, and activities of the microbial communities in 16 physicochemically diverse mountainous and glacial soils. We assembled 451 metagenome-assembled genomes from 18 microbial phyla and inferred through Bayesian divergence analysis that the dominant lineages present are likely native to Antarctica. In support of earlier findings, metagenomic analysis revealed that the most abundant and prevalent microorganisms are metabolically versatile aerobes that use atmospheric hydrogen to support aerobic respiration and sometimes carbon fixation. Surprisingly, however, hydrogen oxidation in this region was catalyzed primarily by a phylogenetically and structurally distinct enzyme, the group 1l [NiFe]-hydrogenase, encoded by nine bacterial phyla. Through gas chromatography, we provide evidence that both Antarctic soil communities and an axenic Bacteroidota isolate (Hymenobacter roseosalivarius) oxidize atmospheric hydrogen using this enzyme. Based on ex situ rates at environmentally representative temperatures, hydrogen oxidation is theoretically sufficient for soil communities to meet energy requirements and, through metabolic water production, sustain hydration. Diverse carbon monoxide oxidizers and abundant methanotrophs were also active in the soils. We also recovered genomes of microorganisms capable of oxidizing edaphic inorganic nitrogen, sulfur, and iron compounds and harvesting solar energy via microbial rhodopsins and conventional photosystems. Obligately symbiotic bacteria, including Patescibacteria, Chlamydiae, and predatory Bdellovibrionota, were also present. We conclude that microbial diversity in Antarctic soils reflects the coexistence of metabolically flexible mixotrophs with metabolically constrained specialists.DATA AVAILABILTY: All amplicon sequencing data, raw metagenomes, metagenomic assemblies, and metagenome-assembled genomes were deposited to the National Center for Biotechnology Information (NCBI) Sequence Read Archive under the BioProject accession no. PRJNA630822. All other study data are included in the article and/or supporting information.An Australian Research Council Discovery Early Career Researcher Award (ARC DECRA) Fellowship, an Australian Antarctic Division grant, a South African National Antarctic Program grant, a National Health & Medical Research Council Emerging Leadership 2 (NHMRC EL2) Fellowship, an Australian Government Research Training Stipend Scholarship, a Monash International Tuition Scholarship, a Monash Postgraduate Publications Award, a South African National Antarctic Programme (SANAP) postdoctoral grant.https://www.pnas.orghj2022BiochemistryGeneticsMicrobiology and Plant Patholog

On-farm trial on the effectiveness of the nitrification inhibitor DMPP indicates no benefits under commercial Australian farming practices

The trend of increasing nitrogen (N) fertilisation in commercial agriculture demands mitigation of negative impacts on the environment, such as emissions of the potent greenhouse gas nitrous oxide (N2O). Laboratory and controlled field experiments have demonstrated that the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) has the potential to effectively mitigate N2O emissions from dairy pasture and crop farming, and may increase yields. Yet, this has not been investigated in on-farm research trials under commercial production conditions. During the winter growing seasons 2014–2016 we performed an on-farm trial on five commercial broad-acre cropping and five dairy farms in North-East Victoria, Australia, to compare the performance of DMPP + urea (treatment) against conventional urea (control) fertiliser in mitigating N2O emissions and increasing crop and pasture yields. Application rate was fixed at the regional industry standard of 46 kg N ha‐1, yet timing, number of applications and all other management decisions were left to the judgement of the participating farmers. Emissions of N2O were highly variable over time and between farms. We recorded emission spikes of up to 250 g N2O-N h

Technical Note: Disturbance of soil structure can lead to release of entrapped methane in glacier forefield soils

Investigations of sources and sinks of atmospheric CH4 are needed to understand the global CH4 cycle and climate-change mitigation options. Glaciated environments might play a critical role due to potential feedbacks with global glacial meltdown. In an emerging glacier forefield, an ecological shift occurs from an anoxic, potentially methanogenic subglacial sediment to an oxic proglacial soil, in which soil-microbial consumption of atmospheric CH4 is initiated. The development of this change in CH4 turnover can be quantified by soil-gas profile analysis. We found evidence for CH4 entrapped in glacier forefield soils when comparing two methods for the collection of soil-gas samples: a modified steel rod (SR) designed for one-time sampling and rapid screening (samples collected ∼1 min after hammering the SR into the soil), and a novel multilevel sampler (MLS) for repetitive sampling through a previously installed access tube (samples collected weeks after access-tube installation). In glacier forefields on siliceous bedrock, sub-atmospheric CH4 concentrations were observed with both methods. Conversely, elevated soil-CH4 concentrations were observed in calcareous glacier forefields, but only in samples collected with the SR, while MLS samples all showed sub-atmospheric CH4 concentrations. Time-series of SR soil-gas sampling (additional samples collected 2, 3, 5, and 7 min after hammering) confirmed the transient nature of the elevated soil-CH4 concentrations, which were decreasing from ∼100 μL L−1 towards background levels within minutes. This hints towards the existence of entrapped CH4 in calcareous glacier forefield soil that can be released when sampling soil-gas with the SR. Laboratory experiments with miniature soil cores collected from two glacier forefields confirmed CH4 entrapment in these soils. Treatment by sonication and acidification resulted in a massive release of CH4 from calcareous cores (on average 0.3–1.8 μg CH4 (g d.w.)−1) (d.w. – dry weight); release from siliceous cores was 1–2 orders of magnitude lower (0.02–0.03 μg CH4 (g d.w.)−1). Clearly, some form of CH4 entrapment exists in calcareous glacier forefield soils, and to a much lesser extent in siliceous glacier forefield soils. Its nature and origin remain unclear and will be subject of future investigations.ISSN:1726-4170ISSN:1726-417

Drivers of Plot-Scale Variability of CH4 Consumption in a Well-Aerated Pine Forest Soil

While differences in greenhouse gas (GHG) fluxes between ecosystems can be explained to a certain degree, variability of the same at the plot scale is still challenging. We investigated the spatial variability in soil-atmosphere fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) to find out what drives spatial variability on the plot scale. Measurements were carried out in a Scots pine (Pinus sylvestris L.) forest in a former floodplain on a 250 m2 plot, divided in homogenous strata of vegetation and soil texture. Soil gas fluxes were measured consecutively at 60 points along transects to cover the spatial variability. One permanent chamber was measured repeatedly to monitor temporal changes to soil gas fluxes. The observed patterns at this control chamber were used to standardize the gas fluxes to disentangle temporal variability from the spatial variability of measured GHG fluxes. Concurrent measurements of soil gas diffusivity allowed deriving in situ methanotrophic activity from the CH4 flux measurements. The soil emitted CO2 and consumed CH4 and N2O. Significantly different fluxes of CH4 and CO2 were found for the different soil-vegetation strata, but not for N2O. Soil CH4 consumption increased with soil gas diffusivity within similar strata supporting the hypothesis that CH4 consumption by soils is limited by the supply with atmospheric CH4. Methane consumption in the vegetation strata with dominant silty texture was higher at a given soil gas diffusivity than in the strata with sandy texture. The same pattern was observed for methanotrophic activity, indicating better habitats for methantrophs in silt. Methane consumption increased with soil respiration in all strata. Similarly, methanotrophic activity increased with soil respiration when the individual measurement locations were categorized into silt and sand based on the dominant soil texture, irrespective of the vegetation stratum. Thus, we suggest the rhizosphere and decomposing organic litter might represent or facilitate a preferred habitat for methanotrophic microbes, since rhizosphere and decomposing organic are the source of most of the soil respiration

Experiments with oenological methods to increase the spicy aroma in Austrian Grüner Veltliner wines

Grüner Veltliner is Austria's most important grape variety, accounting for 32.5% of the vineyard area (a total of around 14,500 ha). There is a noticeable trend with this variety away from fresh, fruity wines towards more spicy, single-vineyard wines. This is especially true for export-oriented producers. The aim of this scientific study is to test oenological methods for increasing the leading substance of the spicy aroma, the sesquiterpene rotundone and to sensory evaluate the wines. The methods skin contact, full and partial fermentation on the skins, addition of whole grapes and or leaves were tested in two independent experimental designs. The wines were analysed using a SPE-SPME-GC-TQMS method. The "retro-tratitional methods" of winemaking mentioned in the article can enhance the spiciness of the wines to a certain degree. Especially the addition of whole grapes as well as partial maceration gave the best results here. The increase in spiciness was observed both sensorially and analytically, as evidenced by higher rotundone contents. However, in summary, it must be stated that the results indicate that an exclusive analysis of rotundone, without the inclusion of phenols and other volatile substances, cannot contribute to a full understanding of the matter, which is based on the interaction of many components. Further analysis both sensory and analytical involving many volatile compounds and phenols are therefore absolutely necessary