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Two panels by Marco d'Oggiono – a painter who was active at the end of the 15th century in Leonardo's workshop in Milan – were investigated by Macro X-ray fluorescence spectroscopy and VNIR hyperspectral imaging. The paintings depict St. Francis and St. Anthony of Padua, each presenting a devotee, and are part of the permanent collection of the Pinacoteca di Brera in Milan. They are two of the five still known compartments of the Maleo polyptich, which originally consisted of ten panels. Preliminarily analyses suggested the presence of ancient over-paintings that modified the arrangement of the hair of one devotee and partially changed the dress of the other one. The paper reports the results obtained by investigating the repainted areas by a new mobile apparatus for MA-XRF and by an innovative compact VNIR hyperspectral camera. The aim is to obtain information on the materials and – possibly – on the original appearance of the modified representations. The two instrumental approaches produced images related to the different superimposed painting layers, which supported the interpretation of the subsequent phases of the production of the paintings and highlighted the evolution of the appearance of the subjects.

International audience; BACKGROUND:FOLFIRINOX (leucovorin, 5-fluorouracil, irinotecan, and oxaliplatin) is an option for fit patients with metastatic (MPC) and locally advanced unresectable (LAPC) pancreatic cancer. However, no criteria reliably identify patients with better outcomes.PATIENTS AND METHODS:We investigated putative prognostic factors among 137 MPC/LAPC patients treated with triplet chemotherapy. Association with 6-month survival status (primary endpoint) was assessed by multivariate logistic regression models. A nomogram predicting the risk of death at 6 months was built by assigning a numeric score to each identified variable, weighted on its level of association with survival. External validation was performed in an independent data set of 206 patients. The study was registered at ClinicalTrials.gov (NCT03590275).RESULTS:Four variables (performance status, liver metastases, baseline carbohydrate antigen 19-9 level, and neutrophil-to-lymphocyte ratio) were found to be associated with 6-month survival by multivariate analysis or had sufficient clinical plausibility to be included in the nomogram. Accuracy was confirmed in the validation cohort (C index = 0.762; 95% confidence interval, 0.713-0.825). After grouping all cases, 4 subsets with different outcomes were identified by 0, 1, 2, or > 2 poor prognostic features (P < .0001).CONCLUSION:The nomogram we constructed accurately predicts the risk of death in the first 6 months after initiation of FOLFIRINOX in MPC/LAPC patients. This tool could be useful to guide communication about prognosis, and to inform the design and interpretation of clinical trials.

The nanoscale coating of particles of a material with a dissimilar compound is an effective tool to engineer its surface, microstructural characteristics and functional properties. The method of using core-shell powders followed by an appropriate method of sintering is a very successfull route to obtain desired microstructures with various degrees of connectivity in ceramic composites. Core-shell multiferroic nanocomposites formed by a magnetic core ( -Fe2O3) and BaTiO3 ferroelectric shell were prepared and then densified either by classical sintering at various temperatures (10500C- 11500C) or by spark plasma sintering [1]. By employing various sintering strategies, dense and homogeneous ceramics were produced with: (ii) di-phase compositions with fully isolated hematite regions within a BaTiO3 matrix (0-3 connectivity), (ii) multi-phase compositions, as result of the interface reactions between constituents. Besides the properties of the parent materials Fe2O3 and BaTiO3, variable amounts of secondary phases (Fe3O4, BaFe12O19 and Ba12Fe28Ti15O84) have driven to new functional properties in the ceramic composites. Dielectric, tunability and magnetic properties were determined and discussed in correlation with the sample microstructures, composition and degree of connectivity. The ceramics show interesting dielectric characteristics, with dielectric constant of 100-300 and low losses by comparison with BaTiO3-based magnetoelectric composites produced by other methods and reduced hoping conductivity contribution due to the isolation of the low-resistivity magnetic phase [2]. In addition, dielectric tunability was determined for the best dielectric composites and multipolar contributions to the dielectric non-linearity were found. Peculiar magnetic properties, including "wasp-waisted" constricted M(H) loops were determined as result of the formation of magnetic phases with contrasting magnetic coercivities (hard and soft phases). The present results demonstrate the usefulnessof the core-shell approach in driving new functional properties in multifunctionalcomposites by an appropriate control of the in situ solid-state nanoscale interface reactions. Acknowledgements: This work was supported by the Romanian CNCSISPCCEID-76 grant under the RAMTECH centre. References: [1] M.T. Buscaglia et al., Chem. Mater. 22, 4740-4748 (2010) [2] L.P. Curecheriu et al., J. Appl. Phys.107, 104106 (2010) [3] A. Stancu et al., Appl. Phys. Lett. 83, 3767-3669 (2003).

Yb-modified CaTiO3 ceramics sintered for 24 h at 1450 °C exhibit a giant apparent permittivity of about 10(4) with a remarkable temperature (30-300 K) and frequency (101-106 Hz) stability (maximum variation: ±20%). After a post-annealing treatment of 48 h at 1100 °C, the dielectric response is strongly modified, with a high frequency, low temperature permittivity corresponding to the intrinsic dielectric behaviour of CaTiO3. A step-like rise in the apparent permittivity and a complex dielectric behaviour is observed with increasing temperature. The overall dielectric response of the ceramics can be interpreted in terms of the Maxwell-Wagner interfacial relaxation and modelled using equivalent circuits. The analysis demonstrates that the as-sintered ceramic consists of semiconducting grains (resistivity

Time-domain THz transmission and FTIR reflectivity spectra of dense core?shell composites of the BaZr0.2Ti0.8O3, BaZr0.4Ti0.6O3, Ba0.66Sr0.34TiO3 and Ba0.45Sr0.55TiO3 compositions were studied in a broad temperature range of 10?900?K. The spectra were evaluated to obtain the complex dielectric functions and at room temperature they were compared with the prediction of the generalized brick-wall model based on the effective medium approximation. The model was analysed concerning the dielectric losses and electric-field tunability below the polar phonon frequency range. Whereas the predicted losses are much reduced compared with those of the cores, the observed enhanced losses in the THz range give evidence of an interdiffusion of the BaTiO3 cores into the shells.

Spark Plasma Sintering (SPS) has been successfully applied in the sintering of nanocrystalline BaTiO3 and gamma-Al2O3 in order to reach fully dense nanostructured ceramics at moderate pressure and temperature. BaTiO3 compacts with densities exceeding 97% and gain size of 50 nm have thus been prepared at temperatures not exceeding 850degreesC using a uniaxial pressure of 100MPa. The selection of sintering temperature is critical for the purpose of minimizing grain growth and there is a demarcation temperature (820degreesC) between normal and abnormal grain growth for the nanocrystalline BaTiO3 powder used in this study. Fully dense alpha-Al2O3 compacts containing grains of the size 300nm or less were consolidated from high-purity gamma-Al2O3 powders without the use of additives or seeds. The transition temperature of gamma-Al2O3 to alpha-Al2O3 can be lowered to 960degreesC when gamma-Al2O3 powder is compacted in the SPS apparatus. The possible mechanisms related to this low transition temperature and to the sintering of both BaTiO3 and gamma-Al2O3 are discussed with special reference to the effect of the pulsed electric field generated by the pulsed electrical current used to heat the sample.

The formation of fine BaTiO3 particles by reaction between liquid TiCl4 and Ba(OH)(2) in aqueous solution at 85 degreesC and pH greater than or equal to 13 has been studied for 0.062less than or equal to[Ba2+]less than or equal to0.51 mol l(-1). The concentration of Ba2+ ions has a strong influence on reaction kinetics, particle size and crystallite size. When [Ba2+]> approximate to0.12 mol l(-1), the precipitate consists of nanosized (approximate to30 nm) to submicron (100-300 nm) particles of crystalline BaTiO3. At lower concentrations, the final product is a mixture of crystalline BaTiO3 and a Ti-rich amorphous phase even for very long reaction times. A two-steps. precipitation mechanism is proposed. Initially, a Ti-rich amorphous precipitate is rapidly produced. Reaction between the amorphous phase and the Ba2+ ions left in solution then leads to crystallisation of BaTiO3. In addition to nucleation and growth of nanocrystals, the final size and morphology of BaTiO3 particles obtained at low concentration can be determined by aggregation of nanocrystals and heterogeneous nucleation on existing crystal surfaces.