Porosity variations in saline media containing humidity are induced by temperature gradients. A temperature imposed on a porous salt sample prepared with some brine and closed to mass transfer leads to significant variations of porosity in few weeks. Modelling of the experiments permits to understand the processes involved.

After double-strand break induction, formation of γ-H2AX foci due to phosphorylation at Ser-139 of histone H2AX represents an early event of the DNA damage response (DDR). γ-H2AX foci are then rapidly dephosphorylated as signal for the subsequent recruitment of effector proteins. The induction and disappearance of the foci can be, therefore, used to monitor the functioning of the DDR machinery in a cell population exposed to genotoxic stress. Here, we investigated the time-course of γ-H2AX in unstimulated or cultured peripheral lymphocytes in vitro treated with UVB, bleomycin and mitomycin C (MMC). Once the mutagen exposure was performed, cells were harvested at different interval times from 0.5 to 5h. The results show that (i) in 20-h stimulated peripheral lymphocytes, UVB irradiation caused extensive and dose-dependent increases in nuclear phosphorylation, and disappearance of γ-H2AX foci progressed, proportionally to the UV fluence, with increasing the harvesting time; (ii) UVB-exposed G0 cells cultured for 20-h post-irradiation displayed low amounts of DNA phosphorylation, depicting a time-course in which the maximum effect was reached at 0.5h and dephosphorylation started after 1h; (iii) treatment of unstimulated lymphocytes with bleomycin sulphate induced an increase in nuclear phosphorylation of several folds higher than that of untreated cells, depicting kinetics comparable to those observed for UVB-exposed G1 cells; (iv) in stimulated cells, MMC caused a severe and dose-dependent high degree of H2AX phosphorylation together with a very slower kinetic of dephosphorylation with respect to the other experimental treatments. This study confirms the feasibility of the γ-H2AX focus assay as a genotoxic end-point and supports the view that the proposed type of analysis should be introduced in biomonitoring studies of human populations. This could also represent a feasible and useful tool in the screening and diagnosis of precancerous states or very early stages of other diseases.

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Quarry lakes resulting from alluvium extraction have excavation depths that can reach the shallow aquifer and extend beyond the piezometric surface. Similar to natural lakes, pit lakes are subject to eutrophication process, both during and after quarrying activity; during mining activity, the eutrophic level is strongly controlled by the excavation method. The present study describes the trophic status of several quarry lakes in the Piedmont plain (north-western Italy) that were evaluated by applying classifications from scientific literature. Most of the studied quarry lakes were mesotrophic or eutrophic, and a slight worsening of water quality was observed over time. In addition, the paper focuses on the pit lake water quality and pit dimension; it was shown that lakes with a larger depth and volume generally had a lower tendency towards eutrophication. At last some management strategies were suggested to achieve environmental sustainability.

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