Alfonso Pedone

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Two series of glasses of general formula (2-p) SiO2.1.1Na2O.CaO.pP2O5.xZnO (p=0.10, 0.20; x=0.0, 0.16, 0.35, and 0.78) have been analyzed for physico-chemical surface features before and after contact with simulated body fluid, morphological characteristics, and osteoblast-like cells behavior when cultured on them. The resulted good cell adhesion and(More)
The structural properties of phosphosilicate glasses based on the 45S5 Bioglass doped with gallium and aluminum (46.2 SiO2·24.3Na2O·26.9CaO·2.6P2O5·1.0X2O3, X = Ga or Al) are investigated by means of classical molecular dynamics simulations. Structural features of the two compositions are compared with those of the original 45S5 Bioglass in order to relate(More)
Carotenoid molecules are essential for the life of photosynthetic organisms in that they protect the cell from the photo-oxidative damage induced by light-stress conditions. One of the photo-protective mechanisms involves triplet-triplet energy transfer from the chlorophyll molecules to the carotenoids: a process that is strongly dependent on the electronic(More)
An integrated computational method which couples classical molecular dynamics simulations with density functional theory calculations is used to simulate the solid-state NMR spectra of amorphous CaSiO(3). Two CaSiO(3) glass models are obtained by shell-model molecular dynamics simulations, successively relaxed at the GGA-PBE level of theory. The calculation(More)
A new empirical pairwise potential model for ionic and semi-ionic oxides has been developed. Its transferability and reliability have been demonstrated by testing the potentials toward the prediction of structural and mechanical properties of a wide range of silicates of technological and geological importance. The partial ionic charge model with a Morse(More)
The ability of Ce-containing bioactive glasses to inhibit oxidative stress in terms of reduction of hydrogen peroxide, by mimicking the catalase enzyme activity is demonstrated here for the first time. The antioxidant properties of three bioactive glasses containing an increasing amount of CeO2 have been evaluated by following the degradation of hydrogen(More)
The popular AMBER force-field has been extended to provide an accurate description of large and flexible nitroxide free-radicals in condensed phases. New atom types have been included, and relevant parameters have been fitted based on geometries, vibrational frequencies and potential energy surfaces computed at the DFT level for several different classes of(More)
In this work, the glass transition temperature and chemical durability of bioactive phospho-silicate glasses were experimentally determined and correlated to the structural descriptor Fnet derived from classical molecular dynamics simulations. The replacement of CaF2 for Na2O in the parent glass 45S5 enhances both chemical durability and density, while the(More)
⁴³Ca MQMAS NMR spectra of three silica-based glasses in which Ca²⁺ ions play different structural roles have been collected and processed in order to extract the underlying NMR parameter distributions. The NMR parameters have been interpreted with the help of molecular dynamics simulations and DFT-GIPAW calculations. This synergetic(More)
The popular biomolecular AMBER (ff99SB) force field (FF) has been extended with new parameters for the simulations of peptides containing α,α dialkylated residues with cyclic side chains. Together with the recent set of nitroxide parameters [E. Stendardo, A. Pedone, P. Cimino, M. C. Menziani, O. Crescenzi and V. Barone, Phys. Chem. Chem. Phys., 2010, 12,(More)