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The 810 nm diode laser, due to its high affinity with haemoglobin (elective chromatophore) revealed, by itself, as elective instrument for surgical excision of the tongue, an organ highly vascularized and sensitive to the laser cutting action. The advantages for its use, with respect to the traditional cold blade surgery, are its haemostatic effect (which avoids to close wounds by stitches) and, not less important, the decontaminant effect of the laser ray, due to either the thermal raising created on cutting line and/or the specific selective action exerted on the bacterial membrane by its wavelength. Finally, the analgesic effect of the diode laser contributes to consider this kind of procedure more comfortable for the patient who often roundly requires its use.

N-body + hydrodynamical simulations of the formation and evolution of galaxy groups and clusters in a LambdaCDM cosmology are used in order to follow the building-up of the colour-magnitude relation in two clusters and in 12 groups. We have found that galaxies, starting from the more massive, move to the Red Sequence (RS) as they get aged over times and eventually set upon a ``dead sequence'' (DS) once they have stopped their bulk star formation activity. Fainter galaxies keep having significant star formation out to very recent epochs and lie broader around the RS. Environment plays a role as galaxies in groups and cluster outskirts hold star formation activity longer than the central cluster regions. However galaxies experiencing infall from the outskirts to the central parts keep star formation on until they settle on to the DS of the core galaxies. Merging contributes to mass assembly until z~1, after which major events only involve the brightest cluster galaxies. The emerging scenario is that the evolution of the colour-magnitude properties of galaxies within the hierarchical framework is mainly driven by star formation activity during dark matter halos assembly. Galaxies progressively quenching their star formation settle to a very sharp ``red and dead'' sequence, which turns out to be universal, its slope and scatter being almost independent of the redshift (since at least z~1.5) and environment. Differently from the DS, the operatively defined RS evolves more evidently with z, the epoch when it changes its slope being closely corresponding to that at which the passive galaxies population takes over the star forming one: this goes from z~1 in clusters down to 0.4 in normal groups., MNRAS in press

Cosmological LambdaCDM TreeSPH simulations of the formation and evolution of galaxy groups and clusters have been performed. The simulations include: star formation, chemical evolution with non-instantaneous recycling, metal dependent radiative cooling, strong star burst and (optionally) AGN driven galactic super winds, effects of a meta-galactic UV field and thermal conduction. We report results on the temperature and entropy profiles of the ICM, the X-ray luminosity, cold fraction, M/L and IMLR ratios in gas and stars, metal abundances and gradients. Besides, the properties of the galaxy populations in the two richest clusters are discussed: global star formation rates of the cluster galaxies, the total K-band luminosity, the galaxy luminosity functions at z=0 and their redshift evolution, the colour-magnitude relation (``red sequence'') as resulting from metallicity effects, and the role of the IMF in reproducing colours and abundances of the stellar populations. Finally the contribute (20-40 %) to cluster light from the intra-cluster stars and the cD galaxy has been investigated: surface brightness profiles, mean colours and chemical abundances, kinematics (velocity dispersion and distributions) of the IC stellar populations., Comment: Conference proceedings, 8 pags., 7 figs

We use a set of twelve high-resolution N-body/hydrodynamical simulations in the $\Lambda$CDM cosmology to investigate the origin and formation rate of fossil groups (FGs), which are X-ray bright galaxy groups dominated by a large elliptical galaxy, with the second brightest galaxy being at least two magnitudes fainter. The simulations invoke star formation, chemical evolution with non-instantaneous recycling, metal dependent radiative cooling, strong star burst driven galactic super winds, effects of a meta-galactic UV field and full stellar population synthesis. We find an interesting correlation between the magnitude gap between the first and second brightest galaxy and the formation time of the group. It is found that FGs have assembled half of their final dark matter mass already at $z\ga1$, and subsequently typically grow by minor merging only, wheras non-FGs on average form later. The early assembly of FGs leaves sufficient time for galaxies of $L \sim L_*$ to merge into the central one by dynamical friction, resulting in the large magnitude gap at $z=0$. A fraction of 33$\pm$16% of the groups simulated are found to be fossil, whereas the observational estimate is $\sim$10-20%. The FGs are found to be X-ray over-luminous relative to non-FGs of the same optical luminosity, in qualitative agreement with observations. Finally, from a dynamical friction analysis is found that only because infall of $L \sim L_*$ galaxies happens along filaments with small impact parameters do FGs exist at all., Comment: 4 pages, 3 figures, one figure removed. Accepted for publication in ApJ Letter

Cosmological (LCDM) TreeSPH simulations of galaxy clusters have been performed, invoking star-formation, chemical evolution with non-instantaneous recycling, metal dependent radiative cooling, strong star-burst and/or AGN driven super-winds, effects of a meta-galactic UV field and thermal conduction. Results for two clusters, one Virgo-like (T~3 keV) and one (sub) Coma-like (T~6 keV), are presented. At z=0, the stellar contents of both clusters consist of a central dominant (cD) galaxy surrounded by galaxies and intracluster (IC) stars. The IC stars are found to contribute 20-40% of the total cluster B-band light and to form at a mean redshift z_f~3, on average about 0.5 Gyr prior to the stars in galaxies. UBVRIJHK surface brightness profiles of the IC star populations are presented; the profile of the larger cluster matches the observed V-band profile of the cD in Abell 1413 (T~8 keV). The IC stellar populations have B-R=1.4-1.5, comparable to larger E galaxies. The mean [Fe/H]~0.0 in the central part of the cluster (r~100 kpc) decreasing to about -0.3 at r_vir. The IC stars are alpha-element enhanced, with a weak trend of [O/Fe] increasing with r, and an overall [O/Fe]~0.4 dex. The IC stars are kinematically colder than the galaxies: The velocity dispersions of the IC stars are at r~100-500 kpc only about half of those of the galaxies increasing to about 70% at r=1-2 Mpc. The projected velocity dispersion in the Virgo-like cluster at R>~50 kpc is 300-600 km/s depending on orientation and R. Rotation is dynamically insignificant for the IC stars. The velocity distributions of IC stars and galaxies are in one cluster highly radially anisotropic, in the other close to isotropic., 12 pages, 14 figures, Final version accepted by MNRAS, Printing in colour recommended

Cosmological (LambdaCDM) TreeSPH simulations of the formation and evolution of galaxy groups and clusters have been performed. The simulations invoke star formation, chemical evolution with non-instantaneous recycling, metal dependent radiative cooling, strong star burst and (optionally) AGN driven galactic super winds, effects of a meta-galactic UV field and thermal conduction. The properties of the galaxy populations in two clusters, one Virgo-like (T~3 keV) and one (sub) Coma-like (T~6 keV), are discussed. The global star formation rates of the cluster galaxies are found to decrease very significantly with time from redshift z=2 to 0, in agreement with observations. The total K-band luminosity of the cluster galaxies correlates tightly with total cluster mass, and for models without additional AGN feedback, the zero point of the relation matches the observed one fairly well. The match to observed galaxy luminosity functions is reasonable, except for a deficiency of bright galaxies (M_B < -20), which becomes increasingly significant with super-wind strength. Results of a high resolution test indicate that this deficiency is not due to ``over--merging''. The redshift evolution of the luminosity functions from z=1 to 0 is mainly driven by luminosity evolution, but also by merging of bright galaxies with the cD. The colour--magnitude relation of the cluster galaxies matches the observed "red sequence" very well and, on average, galaxy metallicity increases with luminosity. As the brighter galaxies are essentially coeval, the colour--magnitude relation results from metallicity rather than age effects, as observed., 15 pages, 10 figures. Final version accepted by MNRAS, presenting new simulations and major changes. Printing in colour recommended

Slovenia is a country of very complex terrain and many problems with air pollution in the valleys, canyons and basins, where industrial air pollution is combined with traffic and domestic heating air pollution, giving rise to problems for the health impact and the ecosystems directly or indirectly. Among indirect effects is also effect on solar radiation budget because of photochemical smog and especially particulate air pollution. To assess air pollutants over the country, a preliminary application of an experimental operational forecast system is presented here, with the aim of exploring its potentials and limitations in modelling the background air quality, and to focus the aspects where improvements are needed for a true operational use.