A direct calculation of the coherent x-ray scattering spectrum of liquid water under ambient conditions is presented using ab initio density functional theory. The experimental data are compared with the calculated x-ray scattering spectra retrieved from the trajectories of two Car–Parrinello molecular dynamics runs of about 10 ps with 32 and 64 water molecules in the simulation cell, respectively. Furthermore, the x-ray spectra obtained from molecular dynamics runs of 20 ps for 128 water molecules using empirical water models are presented. All calculations were performed with the QUICKSTEP code, which includes an all-electron implementation of the Gaussian augmented plane wave method. It is shown that by this approach one can assess how well different models describe the structural properties of water.

Large-area nanocomposite plates (35 cm  35 cm  1 cm) with tuned optical diffusion were successfully prepared. The poly(methyl-methacrylate) matrix is synthesized by bulk polymerization, and "doped" with some ppm of commercial TiO 2 nanoparticles. These are surface modified with 1-octylphosphonic acid in order to stabilize them in the monomer, as shown by repeated Dynamic Light Scattering measurements over long times. TEM images show that the dispersed TiO 2 nanoparticles are aggregated in irregular and porous clusters of about 100 nm in diameter. The size of these aggregates is also confirmed by UV-visible transmission measurements. TEM images of slices prepared from plates confirm that the nanoparticles do not further aggregate during bulk polymerization. Optical diffusion could be characterized in detail, thanks to the large size of the nanocomposites, by using a home-made optical set-up. This allowed the observation of a number of subtle optical effects related to multiple-scattering, and the direct observation of a 'blue sky effect' associated with the small size of the nanoparticles involved in diffusion.

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In our current practice we consider the following preoperative factors to select patients suitable for IORT: age > 50 years, absence of lobular histology, tumor size ≤ 2 cm, pN0 or pNmic, according to APBI consensus statement, including also ki67 ≤ 20%, non triple negative receptor status and G1-G2.

We studied by ab initio molecular dynamics the modifications induced on fullerite by irradiation with ultrashort, very intense laser pulses. We identified the threshold for the nonthermal cage opening of the C 60 molecules that is the analog of the laser-induced nonthermal melting observed in semiconductors and graphite. The new phase formed by the nonthermal coalescence of the C 60 molecules is fluidlike and mainly formed by small chains of twofold-coordinated atoms. An estimate of the threshold laser fluence for the nonthermal transformation is given.