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<p>In this work, we will present 4 different approaches to study and visualize the effects of motorway infrastructures such as precast noise barriers or vegetated flat-top earth berms on the dispersion of traffic-related pollutants. The micrometeorological characteristics that directly affect the dispersion of pollutants in the atmosphere were first computed with a pseudo-3-dimensional CFD model by means of the openFoam toolbox. The strengths of this model based on the Reynolds-Averaged Navier–Stokes (RANS) equations with K-ε first-order closure model is to consider the traffic-induced momentum and turbulence (Letaïef et al., 2020). A second approach was to directly visualize the microturbulence from a 1/100 scale model of the motorway cross-section in a wind tunnel. To this end, we refracted the beam of a laser light with a glass rod to observe eddies along a thin plane through a fog generated by a fog machine. Simple shots with a camera can reveal coherent patterns in the chaos. To complete these two models, we conducted two types of field measurements of fine particle concentrations on the studied motorway sector. Direct and indirect measurements were carried out with low-cost microsensors and with environmental magnetism tools applied on dust depositions on accumulating surfaces (Hofman et al., 2017), respectively.</p> <p>These four approaches indicates similar results. A large recirculation wake region formed on the leeward side of the wall that brings back to the wall the pollutant generated by the traffic is evidenced. On the contrary, flat-top earth berms favor the dispersion of pollutants in the atmosphere. These 4 different approaches allowed us not only to establish these conclusions but also to communicate with all the actors concerned by this study site: scientists specialized in the metrology of atmospheric pollutants, the persons in charge of the motorway company, the elected representatives and the inhabitants of the city where the study site is located. </p> <p>References:</p> <p>Hofman, J., Maher, B. A., Muxworthy, A. R., Wuyts, K., Castanheiro, A., and Samson, R.: Biomagnetic Monitoring of Atmospheric Pollution: A Review of Magnetic Signatures from Biological Sensors, Environ Sci Technol, 51, 6648–6664, https://doi.org/10.1021/acs.est.7b00832, 2017.</p> <p>Letaïef, S., Camps, P., Poidras, T., Nicol, P., Bosch, D., and Pradeau, R.: Biomagnetic monitoring vs. CFD modeling: A real case study of near-source depositions of traffic-related particulate matter along a motorway, Atmosphere, 11, 1–23, https://doi.org/10.3390/atmos11121285, 2020.</p>

<p>At the moment, air quality is a major concern for human and environmental health. The challenge is to produce a robust air pollution mapping for different metrological contexts. In optical physics, the development of particulate matters counters is in full expansion, but the calibration is time-consuming and is difficult to achieve. To answer this problem, many alternatives have been developed as environmental magnetism applied to dust deposition on accumulative surfaces (plant leaves, barks, paper filters,…). In this context, our study focuses on the characterization of the influence of road traffic on air quality along the western bypass of the city of Montpellier (south of France). This work was requested by the Vinci ASF company, in charge of the requalification. </p> <p>We chose to work with a mixed approach to be able to free ourselves from the influence of environmental variables. We used local vegetation by selecting species with a good spatial distribution and a capacity of capture of particulates matter (PM) recognized in the literature. Our choice was <em>Pinus pinea, Pinus halepensis,</em> and <em>Arundo</em> <em>donax</em>. In order to support the measurements obtained from these plants, we also used passive cellulose filters (Cao et al. method, 2015). The idea was to plot the relative concentrations of the pollutants (Letaïef et al. 2020)<strong> </strong>measured for each type of sensor on a map, and to compare them to each other. These concentrations were obtained with saturation isothermal magnetization (sIRM, 1000 mT). Finally, to complete this field analysis we plan to use low-cost PM counters (<em>Alphasens</em> model, prototyped by Thierry Poidras). The results show that the highest concentrations are most often associated with partitioned areas and heterogeneous traffic (acceleration and braking). Another interesting result shows that vehicles emit more PM at the exit of a roundabout than at the entrance of it. To characterize the source of the pollutants, we are currently doing a series of complementary analyses. These series include mineralogy analyses on SEM images, hysteresis cycles, and KT curves. Finally, as plant leaf characteristics (macro and micromorphology) influence PM sorption, we also plan to compare the uptake efficiency of our selected species through an experiment within our wind tunnel, the ZephyrLAB (Saint-Aunès, south of France).</p> <p><strong>References </strong></p> <p>Cao, Liwan, Erwin Appel, Shouyun Hu, et Mingming Ma. 2015. « An Economic Passive Sampling Method to Detect Particulate Pollutants Using Magnetic Measurements ». <em>Environmental Pollution</em> 205 (octobre): 97‑102. https://doi.org/10.1016/j.envpol.2015.05.019.</p> <p>Letaïef, Sarah, Pierre Camps, Thierry Poidras, Patrick Nicol, Delphine Bosch, et Romane Pradeau. 2020. « Biomagnetic Monitoring vs. CFD Modeling: A Real Case Study of Near-Source Depositions of Traffic-Related Particulate Matter along a Motorway ». <em>Atmosphere</em> 11 (12): 1285. https://doi.org/10.3390/atmos11121285.</p>

Objectives: Interstitial lung disease (ILD) is relatively common in patients with lung cancer with an incidence of 7.5%. Historically pre-existing ILD was a contraindication to radical radiotherapy owing to increased radiation pneumonitis rates, worsened fibrosis and poorer survival compared with non-ILD cohorts. Herein, the clinical and radiological toxicity outcomes of a contemporaneous cohort are described. Methods: Patients with ILD treated with radical radiotherapy for lung cancer at a regional cancer centre were collected prospectively. Radiotherapy planning, tumour characteristics, and pre- and post-treatment functional and radiological parameters were recorded. Cross-sectional images were independently assessed by two Consultant ThoracicRadiologists. Results: Twenty-seven patients with co-existing ILD received radical radiotherapyFebruary 2009–April 2019, with predominance ofusual interstitial pneumonia subtype (52%). According to ILD-GAP scores, most patients were stage I. After radiotherapy, localised (41%) or extensive (41%) progressive interstitial changes were noted for most patients yetdyspnoea scores (n = 15 available) and spirometry (n = 10 available) were stable. One-third of patients with ILD went on to receive long-term oxygen therapy, which was significantly more than the non-ILD cohort. Median survival trended towards being worse compared with non-ILD cases (17.8 v 24.0 months, p = 0.834). Conclusions: Radiological progression of ILD and reduced survival were observed post-radiotherapy in this small cohort receiving lung cancer radiotherapy, although a matched functional decline was frequently absent. Although there is an excess of early deaths, long-term disease control is achievable. Advances in knowledge: For select patients with ILD long-term lung cancer control without severely impacting respiratory function may be possible with radical radiotherapy, albeit with a slightly higher risk of death.

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