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The main goal of the project is to understand the mechanisms of chemical etching to obtain superficial roughness for biomedical applications. The material studied in this project is Yttria Tetragonal Zirconia Polycristal (3Y- TZP). The project is divided in four different parts in order to better understand the microstructure and the damage of different etching conditions. The first one is related to evaluate the different levels of roughness of zirconia, mainly by advanced techniques such as profilometer and atomic force microscopy (AFM). In the second part, the mechanical responses by nanoindentation generated under sharp indentation will be detailed by: laser confocal microscopy and AFM for superficial damage, and focused ion beam (FIB) for sub-superficial damage. A third part involves the statistical study of fracture by Weibull analysis. Finally, the tribological properties of the different speciments will be studied by nanoscratch and wear resistance. These tests permit to understand wether the chemical attacks leave the material's mechanical properties unchanged, with different levels of roughness., Incoming

We acknowledge a paper on the same subject by other authors, that we didn't have the chance to cite in our work. A few comments on the content of the two papers are made., Comment: Addendum to hep-0001265 "A Phenomenological Description of pi- Delta++ photoproduction and electroproduction in nucleon resonance region"

The (\pi^{-}\Delta^{++}) production on the nucleon by real and virtual photons is discussed as initial step in a simple model approach for the two pion photo- and electroproduction on the nucleon, with emphasis on nucleon resonance excitation which is of interest for new facilities like TJNAF. A calculation for (\pi^{-}\Delta^{++}) channel in resonance excitation region is presented and compared to existing experimental data along with a discussion of physical effects that we find to be of relevance. The calculation is proposed as a starting basis for the investigation of (N^{*}) electromagnetic form factors using experimental data about two pion production by real and virtual photons., Comment: 36 pages, 14 figures, to be published in Nucl. Phys. A