ANFO vapour detection with conducting polymer percolation network sensors and GC/MS

Ammonium nitrate mixed with fuel oil (ANFO) is commonly used in improvised explosive devices (IEDs). The development of ANFO vapour sensors that are small, inexpensive, and easy to use will enable widespread IED detection in the context of security and humanitarian demining. Because of concealment and the low vapour pressures of most explosive materials, achieving sufficiently high sensitivity and low limits of detection are some of the main challenges of explosives vapour detection. Here ANFO chemiresistive vapour sensors based on polypyrrole (PPy) percolation networks are presented and compared to gas chromatography-mass spectroscopy (GC/MS) results for ANFO. Improved sensitivities are achieved by using a polymer percolation network instead of a thin film for the gas sensors. Vapour concentrations are detected of 13–180 ppb of ammonia emitted by a variety of different ammonium nitrate-containing fertilisers and fertiliser-diesel mixtures

Time-Course of Changes in Inflammatory Response after Whole-Body Cryotherapy Multi Exposures following Severe Exercise

The objectives of the present investigation was to analyze the effect of two different recovery modalities on classical markers of exercise-induced muscle damage (EIMD) and inflammation obtained after a simulated trail running race. Endurance trained males (n = 11) completed two experimental trials separated by 1 month in a randomized crossover design; one trial involved passive recovery (PAS), the other a specific whole body cryotherapy (WBC) for 96 h post-exercise (repeated each day). For each trial, subjects performed a 48 min running treadmill exercise followed by PAS or WBC. The Interleukin (IL) -1 (IL-1), IL-6, IL-10, tumor necrosis factor alpha (TNF-α), protein C-reactive (CRP) and white blood cells count were measured at rest, immediately post-exercise, and at 24, 48, 72, 96 h in post-exercise recovery. A significant time effect was observed to characterize an inflammatory state (Pre vs. Post) following the exercise bout in all conditions (p<0.05). Indeed, IL-1β (Post 1 h) and CRP (Post 24 h) levels decreased and IL-1ra (Post 1 h) increased following WBC when compared to PAS. In WBC condition (p<0.05), TNF-α, IL-10 and IL-6 remain unchanged compared to PAS condition. Overall, the results indicated that the WBC was effective in reducing the inflammatory process. These results may be explained by vasoconstriction at muscular level, and both the decrease in cytokines activity pro-inflammatory, and increase in cytokines anti-inflammatory

Performance of non-invasive tests and histology for the prediction of clinical outcomes in patients with non-alcoholic fatty liver disease: an individual participant data meta-analysis

BackgroundHistologically assessed liver fibrosis stage has prognostic significance in patients with non-alcoholic fatty liver disease (NAFLD) and is accepted as a surrogate endpoint in clinical trials for non-cirrhotic NAFLD. Our aim was to compare the prognostic performance of non-invasive tests with liver histology in patients with NAFLD.MethodsThis was an individual participant data meta-analysis of the prognostic performance of histologically assessed fibrosis stage (F0–4), liver stiffness measured by vibration-controlled transient elastography (LSM-VCTE), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS) in patients with NAFLD. The literature was searched for a previously published systematic review on the diagnostic accuracy of imaging and simple non-invasive tests and updated to Jan 12, 2022 for this study. Studies were identified through PubMed/MEDLINE, EMBASE, and CENTRAL, and authors were contacted for individual participant data, including outcome data, with a minimum of 12 months of follow-up. The primary outcome was a composite endpoint of all-cause mortality, hepatocellular carcinoma, liver transplantation, or cirrhosis complications (ie, ascites, variceal bleeding, hepatic encephalopathy, or progression to a MELD score ≥15). We calculated aggregated survival curves for trichotomised groups and compared them using stratified log-rank tests (histology: F0–2 vs F3 vs F4; LSM: 2·67; NFS: 0·676), calculated areas under the time-dependent receiver operating characteristic curves (tAUC), and performed Cox proportional-hazards regression to adjust for confounding. This study was registered with PROSPERO, CRD42022312226.FindingsOf 65 eligible studies, we included data on 2518 patients with biopsy-proven NAFLD from 25 studies (1126 [44·7%] were female, median age was 54 years [IQR 44–63), and 1161 [46·1%] had type 2 diabetes). After a median follow-up of 57 months [IQR 33–91], the composite endpoint was observed in 145 (5·8%) patients. Stratified log-rank tests showed significant differences between the trichotomised patient groups (p<0·0001 for all comparisons). The tAUC at 5 years were 0·72 (95% CI 0·62–0·81) for histology, 0·76 (0·70–0·83) for LSM-VCTE, 0·74 (0·64–0·82) for FIB-4, and 0·70 (0·63–0·80) for NFS. All index tests were significant predictors of the primary outcome after adjustment for confounders in the Cox regression.InterpretationSimple non-invasive tests performed as well as histologically assessed fibrosis in predicting clinical outcomes in patients with NAFLD and could be considered as alternatives to liver biopsy in some cases

Impacts du changement climatique et de la pollution de l’air sur l’agriculture

Although some uncertainties remain, the expected effects of climate change on agricultural production and its economic consequences are now relatively well identified. In order to develop adaptation strategies for agriculture, this knowledge is generally integrated into models which are tested with diverse scenarios of climate change. However, these models do not take into account other constraints such as regional pollution, which can significantly affect crop response to climate change. Thus, to be able to provide relevant adaptation strategies for the future, it will be necessary to develop models coupling both climate impacts and other environmental constraints

Agriculture et pollution de l'air : Impact sur les écosystèmes - Introduction

Agriculture et pollution de l'air : Impact sur les écosystèmes - Introduction. Agriculture et Qualité de l'Ai

Impacts de l’ozone sur l’agriculture et les forêts et estimation des coûts économiques

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Foliar surface cleaning techniques for analysis of particulate chemical composition in aire pollutants monitoring

Foliar surface cleaning techniques for analysis of particulate chemical composition in aire pollutants monitoring. 27th Task Force Meeting of the ICP Vegetatio

Validity of usual dose-response functions in the case of wheat exposed to free-air fumigation in the Paris region

Two wheat varieties (Premio and Soissons) were grown in the field in the Paris region and exposed to moderate levels of ozone through a 50m long linear free-air fumigation device. Plants were ozone-fumigated daily for 56 days (from 12 May to 6 July 2009). O3 exposures at 3 different distances from the fumigation source: 2 m, 3.5 m and 5 m downwind of the source, were compared to control located 15m upwind of the linear source. Hourly average concentrations and cumulative exposure index (AOT40) were calculated. Stomatal conductance measurements and modelling allowed the calculation of the Phytotoxic Ozone Dose (POD06) absorbed by the upper leaves of the canopy. The results show strong correlations between grain yield and both ozone exposure (AOT40 or POD06) indicators. However, there are differences in the dose-response relationship obtained for each variety. Moreover, these relationships are also quite different from the dose-response relationships found in the literature. This can be partly explained by the fact that the use of free-air fumigation systems does not allow to achieve a true control treatment (plants exposed to ozone-free air). The highest production values that could be achieved in an atmosphere without ozone must therefore be extrapolated from experimental data, and this may increase the inaccuracy of calculations of relative yield losses

Hypothèses et principes de la représentation de la diffusion du CO2 à différentes échelles, de la feuille au couvert.

International audienc

Contribution de l’agriculture à l’effet de serre

Agriculture contributes to almost 20% of greenhouse gas emissions in France, and the same applies for most EU countries. This is due to a large extent to N2O emission after N fertilizer application, but the emissions are very variable in space and time, due mainly to the variability in environmental conditions. However, the figure of the relationship between agriculture and greenhouse effect is more complex. First a significant fraction of emitted N2O does not occur where N has been applied, but is due to indirect emissions in wetlands or forest where N is transferred by natural pathways. This implies the need to make an assessment at larger scale than the field where N is applied. Many other GHG emissions are more or less directly linked to nitrogen use. Carbon storage in ecosystems in enhanced by nitrogen ; ozone (also a greenhouse gas) is produced by the reaction of N oxides and volatile organic compounds ; fine particles formed by the reaction of ammonia (mainly from agricultural sources) and atmospheric acids can reflect solar radiation. Moreover the negative effect of ozone on photosynthesis could reduce significantly the biospheric CO2 sink in the future. It is thus very complex to make a complete balance of the influence of agriculture on the greenhouse effect and the impact of an agricultural practice or farming system on the greenhouse effect