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Purpose or Objective Inter-observer variability (IOV) in target volume delineation is a well-documented phenomenon and a major source of uncertainty in radiation treatment (RT) planning. The increasing adoption of adaptive RT adds a dynamic component to IOV, which is largely unknown. We analysed IOV in the pre- and mid-treatment (PT and MT) setting using expert primary gross tumour volume (GTV) and clinical target volume (CTV) delineations in locally advanced HNSCC. Material and Methods Five patients from routine clinical practice, who underwent repeat imaging, were selected such that a variety of features likely to prompt adaptation were included. Brief case reports and CT imaging data were sent to five observers, the latter supplemented with pre-therapeutic FDG-PET in four cases. Observers received PT and MT imaging data at least one week apart and were asked to delineate the GTV and CTV in their own treatment planning system and to comment on their delineation process, i.e. on how GTV to CTV expansion and adaptation were performed. Delineations were rasterised on a 1mm³ grid and their compatibility assessed with the Generalised Conformity Index (CIgen). Differences in IOV between PT and MT were probed with Wilcoxon signed-rank tests and the correlation between GTV and CTV IOV evolution with Spearman rank correlation. While it is respectively impossible and very difficult for these tests to show two-sided α=0.05 significance at n=5, more powerful parametric alternatives cannot credibly be employed. Delineations were processed with ITK and statistical analyses performed in R. Results A total of 82/100 delineations were received and analysed. Figure 1 shows an overview of IOV in terms of volume overlap. All cases and volumes suffered a reduction of CIgen when transitioning from PT to MT (p=0.063 for both CTVs and GTVs). There was generally better agreement in CTV than GTV delineations at individual time points, and the correlation between GTV and CTV CIgen changes was very weak (ρ=0.5, p=0.45). This comparative robustness of CTV delineations might stem from GTV to CTV expansion practices, which overwhelmingly employed sizeable isotropic margins (mean: 7.6 mm) and additional editing for anatomical boundaries at both time points. Figure 2 shows a case in which CIgen for CTVs remains stable despite deteriorating IOV in the primary GTV. MT GTV delineations were often based on PT delineations after image registration (14/24 analysed observers and cases), the remainder contoured de novo. Post-transfer adaptation to changed anatomy was performed by two observers and inclusion of the PT GTV in the MT CTV by one. Shortcomings of this contouring challenge are a lack of MRI and contrast-enhanced CT at both time points. Conclusion IOV in target volume delineation increases during treatment, where a disparity in institutional adaptation practices adds to the static causes of IOV. Consensus guidelines are urgently needed and should recommend scope, frequency, and quality of MT imaging alongside adaptation strategies.

Stereotactic body radiation therapy (SBRT) for painful spinal metastases has the potential to improve and extend pain relief, but prospective data on pain response are lacking. This prospective phase II trial addressed the question of overall (complete and partial) pain response after hypo-fractionated SBRT for painful, mechanically stable, previously un-irradiated spinal metastases?

This work aims to establish an ecologically integrated strategy for pest management to assess the impact of water and nitrogen depletion on Aphis pomi infestation in the Apple orchard.The results of the study of the impact on the green Apple aphid show a significant effect on the availability of water and nitrogen on the level of Aphis pomi infestation. Indeed, the normal fertigation regime (T1 = 100%) proved to be more favorable to a prominent development of aphids, in comparison with a 25% water and nitrogen deficit regime (T2 = 75%), that minimize infestation. As for the evolution of wingless aphid and green aphid with wing, the Aphis pomi, at both regimes, the general shape of the evolution of winged curves looks like the one of the wingless ones, with small differences. The number of leaves was higher in the T1 regime than that of T2. Moreover, the study of the orientation effect on the infestation of aphids has shown that the North andthe West sides were more infested than the East and the South ones. A negative effect on Syrphesp and ChrysoperlaCarnea densities was noticed under water and nitrogen depletion.

National audience; The objective of this work is to develop an integrated and ecological pest management strategy to assess the impact of water and nitrogen resources on Myzus persicae infestations in the peach orchard. The results of the peach aphid impact study showed a significant effect of water and nitrogen availability on the level of green peach aphid infestation. Indeed, the normal fertilization regime (T1=100%) was found to be much more favorable to a prominent development of the aphidian populations, while the regime deficit of 25% in water and nitrogen by contribution to the normal diet (T2=75%) was able to minimize the infestations of the latter. At the same time, the study of the effect of orientation on the infestation of the aphid showed that orientations North, West and South were more infested than that of East. As for the auxiliaries and the ants, the treatment carried out revealed a significant effect on their evolution.

This work aims to establish an ecologically integrated pest management strategy to assess the effect of water and nitrogen depletion on Myzus persicae infestation in the peach orchard. The results showed a significant effect of level of water and nitrogen supplies on the green peach aphid infestation in the orchard. Indeed, the fertigation regime T1 (100%) proved to be much more favorable to a prominent development of aphidian populations compared to 25% water and nitrogen restricted regime. Moreover, the infestation degree was lower in the regime T2 (~75%) than that observed in the regime T1. The evolution of wingless and winged green aphid populations was similar in both regimes. The effect of branch orientation on the aphids infestation was significant with those oriented to the North, West and South were more infested than those oriented to the East. Concerning the useful fauna, we noticed the same predators species for all the tested regimes. A negative effect on Stethorus sp and Chrysoperla carnea densities was appeared under water and nitrogen depletion.

This work aims to establish an ecologically integrated pest management strategy to assess the effect of water and nitrogen depletion on Myzus persicae infestation in the peach orchard. The results showed a significant effect of level of water and nitrogen supplies on the green peach aphid infestation in the orchard. Indeed, the fertigation regime T1 (100%) proved to be much more favorable to a prominent development of aphidian populations compared to 25% water and nitrogen restricted regime. Moreover, the infestation degree was lower in the regime T2 (~75%) than that observed in the regime T1. The evolution of wingless and winged green aphid populations was similar in both regimes. The effect of branch orientation on the aphids infestation was significant with those oriented to the North, West and South were more infested than those oriented to the East. Concerning the useful fauna, we noticed the same predators species for all the tested regimes. A negative effect on Stethorus sp and Chrysoperla carnea densities was appeared under water and nitrogen depletion.