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International audience; PURPOSE:Limited pelvic nodal relapse of prostatic cancer is a paramount challenge for locoregional salvage treatments. Salvage whole pelvis radiotherapy as considered in the BLINDED trial, is an attractive option but with concerns about its toxicity. This article describes early toxicity with the technique.METHODS AND MATERIALS:BLINDED was a prospective multi-center phase II trial investigating high-dose salvage pelvic irradiation with an additional dose to the fluorocholine-based positron-emission-tomography (FCH-PET)-positive pelvic lymph nodes (PLN), combined with six-month androgen blockade. The prescribed dose was 54 Gy in 1.8 Gy fractions with up to 66 Gy in 2.2 Gy fractions to the pathological PLN. Early toxicity was defined until one year after radiotherapy. Patients quality of life was assessed using the EORTC questionnaires (QLQ-C30 and QLQ-PR25).RESULTS:Seventy-four patients were recruited in fifteen French radiation oncology departments between August 2014 and July 2016. Seven were excluded before treatment because of violation of the inclusion criteria. The intention-to-treat analysis therefore included sixty-seven patients. Half of them had received prior prostatic irradiation. Median age was 67.7 ± 6.5 years. Grade 2 acute urinary toxicity was observed in 9/67 patients (13.4%) and grade 2 one-year toxicity in 4/67 patients (6%). Three patients (4.4%) had grade 3 urinary toxicity. Grade 2 acute digestive toxicity was observed in 10/67 patients (14.9%) and grade 2 one-year toxicity in 4/67 patients (6%). Patients with prior prostate bed irradiation did not exhibit increased urinary or digestive toxicity. EORTC questionnaire scores at one year did not worsen significantly.CONCLUSIONS:The acute and one-year toxicity of the BLINDED protocol was satisfactory, even in patients with a past history of prostatic irradiation.

In this thesis, we present a new implementation of the constrained Random Phase Approximation (cRPA) in a density functional code within the linearized augmented plane wave (LAPW) framework. The aim is to calculate - from first principles - the effective Coulomb interaction matrix for correlated solids, opening the way to a truly ab initio description within many-body calculations. In particular, we calculate the Hubbard parameter, U, and Hund's exchange, J, as well as their energy dependence arising from dynamical screening effects. As in the Wilson renormalization group, we stress that the effective Coulomb interactions crucially relie on the choice of the correlated subspace for which an effective low-energy Hamiltonian is constructed, although results for physical observables have to be the same at the end. A specific scheme for cRPA, based on a projection approach onto the low-energy subspace, is also introduced in order to deal with electronic structures where the target correlated orbitals are strongly entangled with the itinerant ones. Applications are shown for i) iron-based pnictides, LaOFeAs and BaFe2As2, and chalcogenides, FeSe (Chapter 6), ii) 3d transition metals to benchmark the projection scheme (Chapter 6) and iii) 3d and 4d transition metal perovskites, SrMO3 (M = V, Cr, Mn, Nb, Mo, Tc) and layered perovskites, Sr2MO4 (M = Mo, Tc, Ru, Rh) (Chapter 7). The cRPA values for the interaction Hamiltonian are combined with the dynamical mean-field theory (LDA+cRPA+DMFT) for the description of the spin-orbitally ordered Mott insulator Sr2IrO4, and the rare-earth fluorosulfide pigment, CeSF (Chapter 8)., Cette thèse propose une nouvelle implémentation de "l'approximation de la phase aléatoire avec polarisation contrainte" (constrained random phase approximation, cRPA). Notre implémentation repose sur la théorie de la fonctionnelle de la densité, développée dans une base d'ondes planes augmentées (linearized augmented plane wave, LAPW). Cette méthode, appliquée à des matériaux fortement corrélés, permet de calculer de facon réaliste la matrice d'interaction coulombienne effective, qui pourra être traitée par la suite au moyen de l'approche à N-corps souhaitée. En particulier, les valeurs de l'interaction de Hubbard, U , et de l'échange de Hund, J, sont déterminées de manière ab initio, ainsi que leur dépendance en fréquence qui résulte des effets dynamiques de l'écrantage. Comme dans la théorie du groupe de renormalisation de Wilson, l'interaction coulombienne effective dépend du choix du sous-espace corrélé pour lequel est construit un Hamiltonien effectif de basse énergie, alors que les valeurs des observables physiques n'en dépendent pas. Afin de généraliser la cRPA aux matériaux dont la structure électronique exhibe des orbitales corrélées et itinérantes intriquées, une méthode basée sur la projection sur le sous-espace corrélé est également introduite. Différentes classes de matériaux sont envisagées comme applications : i) pnictides à base de fer, LaOFeAs et BaFe2As2, et chalcogénides, FeSe (Chapitre 6), ii) métaux de transition 3d afin de valider notre méthode de projection (Chapitre 6), iii) oxydes de métaux de transition pérovskites, SrMO3 (M = V, Cr, Mn, Nb, Mo, Tc), et pérovskites en couches, Sr2MO4 (M = Mo, Tc, Ru, Rh) (Chapitre 7). L'Hamiltonien d'interaction cRPA est également couplé à la théorie du champ moyen dynamique (LDA+cRPA+DMFT) afin de décrire l'isolant de Mott induit par le couplage spin-orbite, Sr2IrO4, et le pigment à base de terre rare, CeSF (Chapitre 8).

Systems of adatoms on semiconductor surfaces display competing ground states and exotic spectral properties typical of two-dimensional correlated electron materials which are dominated by a complex interplay of spin and charge degrees of freedom. We report a fully ab initio derivation of low energy Hamiltonians for the adatom systems Si(111):X, with X=Sn, Si, C, Pb, that we solve within self-consistent combined GW and dynamical mean field theory ("GW+DMFT"). Calculated photoemission spectra are in agreement with available experimental data. We rationalize experimentally observed tendencies from Mott physics towards charge-ordering along the series as resulting from substantial long-range interactions., 5 pages, 4 figures

In this work, we address the question of calculating the local effective Coulomb interaction matrix in materials with strong electronic Coulomb interactions from first principles. To this purpose, we implement the constrained random phase approximation (cRPA) into a density functional code within the linearized augmented plane wave (LAPW) framework. We apply our approach to the 3d and 4d early transition metal oxides SrMO3 (M=V, Cr, Mn) and (M=Nb, Mo, Tc) in their paramagnetic phases. For these systems, we explicitly assess the differences between two physically motivated low-energy Hamiltonians: The first is the three-orbital model comprising the t2g states only, that is often used for early transition metal oxides. The second choice is a model where both, metal d- and oxygen p-states are retained in the construction of Wannier functions, but the Hubbard interactions are applied to the d-states only ("d-dp Hamiltonian"). Interestingly, since -- for a given compound -- both U and J depend on the choice of the model, so do their trends within a family of these compounds. In the 3d perovskite series SrMO3 the effective Coulomb interactions in the t2g Hamiltonian decrease along the series, due to the more efficient screening. The inverse -- generally expected -- trend, increasing interactions with increasing atomic number, is however recovered within the more localized "d-dp Hamiltonian". Similar conclusions are established in the layered 4d perovskites series Sr2MO4 (M=Mo, Tc, Ru, Rh). Compared to their isoelectronic and isostructural 3d analogues, the 4d 113 perovskite oxides SrMO3 (M=Nb, Mo, Tc) exhibit weaker screening effects. Interestingly, this leads to an effectively larger U on 4d shells than on 3d when a t2g model is constructed., 21 pages, 7 figures

We discuss the notions of spin-orbital polarization and ordering in paramagnetic materials, and address their consequences in transition metal oxides. Extending the combined density functional and dynamical mean field theory scheme to the case of materials with large spin-orbit interactions, we investigate the electronic excitations of the paramagnetic phases of Sr2IrO4 and Sr2RhO4. We show that the interplay of spin-orbit interactions, structural distortions and Coulomb interactions suppresses spin-orbital fluctuations. As a result, the room temperature phase of Sr2IrO4 is a paramagnetic spin-orbitally ordered Mott insulator. In Sr2RhO4, the effective spin-orbital degeneracy is reduced, but the material remains metallic, due to both, smaller spin-orbit and smaller Coulomb interactions. We find excellent agreement of our ab-initio calculations for Sr2RhO4 with angle-resolved photoemission, and make predictions for spectra of the paramagnetic phase of Sr2IrO4., 4+ pages, 4 figures