Mössbauer studies of the Umbria archeological clays

We report an analysis of two different clays from the region of Umbria (Italy): 1. potteries found one inside and the other outside the town of Todi, dating from the end of the IV century B. C., 2. bond clays of Bagnara (Nocera Umbra) and Colfiorito (Foligno) dating V century B.C.     

Convergence of series of dependent φ-subgaussian random variables

The almost sure convergence of weighted sums of φ-subgaussian m-acceptable random variables is investigated. As corollaries, the main results are applied to the case of negatively dependent and m-dependent subgaussian random variables. Finally, an application to random Fourier series is presented.     

Generating examples: focus on processes

Constructing an example can be a rich and complex activity, interesting to investigate mathematical thinking and with many potentialities in mathematics education. In this article, I analyse processes involved in example generation, with particular emphasis on production and transformation of signs representing mathematical objects and on generation of inferences. The richness and complexity of these processes will also be shown through the notions of prototypes, concept image and concept definition. This investigation reveals aspects that are significant both in education and for the reflection on cognitive and cultural aspects of mathematical thinking.     

Synthesis and 1H NMR characterization of substituted 1-amino-9-imino-4-nitro-9,10-dihydr oacridines as potential antitumor agents

A convenient method for the synthesis of unsubstituted and substituted 1-amino-9-imino-4-nitro-9,10-dihydroacridines, 9 and 10 , respectively, is reported. Their ¹H nmr data are reported and discussed in order to confirm the imino tautomeric structure.     

Microstructural changes in irradiated silica based glasses

High voltage electron microscopy studies have been performed on irradiated pure silica and borosilicate glasses to check their long-term stability when these materials are employed near high energy radioactive sources, such as in fusion reactors and during the storage of nuclear waste. The intense energetic beam of electrons produced by the Harwell 1 MeV microscope, ranging from 10¹⁷ to 10²⁰ e/cm²/s has been focused upon specimens of various composition and impurity content at different temperatures up to about 850°C. Pure silica samples have also been bombarded with 46.5 MeV Ni+6 ions at the Variable Energy Cyclotron. It is found that while no significant changes are detectable in pure irradiated silica, clear evidence is present in complex borosilicate glasses for the growing of large defect clusters (over 1000 Å, resembling gas bubbles) after electron doses of about 8.5 × 10¹⁹ e/cm² and dose rates exceeding 2 × 10¹⁸ e/cm²/sec. Moreover, small regions, about 100 Å wide, scattering electrons more than the matrix are also present. The nature of this fine microstructure has been established as a phase separation into crystalline tridymite. The observations are discussed in terms of their dependence on temperature, sample thickness, dose and dose rates.     

A preliminary study on the migration mechanism of heavy metals into the vadose zone of soils of a dismissed industrial site

Within the framework of the site assessment of a dismantled steel-making plant area contaminated by Electric Arc Furnace dust (EAF dust), the actual migration of Cr, Cu, As, Cd, Pb, Zn and Ni (contaminants) from an industrial waste layer towards the vadose zone of the underlying soil has been evaluated. The crystalline phases and contaminant abundance of samples of the industrial waste layer and the surrounding soils were analysed, while the release of contaminants was evaluated by leaching tests. Results indicate the migration of pollutants from the industrial waste layer into the subsurface soil, but the high leachability of soil hides its real degree of contamination, with the consequent possibility of underestimating the hazardous characteristics of the actual situation.     

Pinus mugo Essential Oil Impairs STAT3 Activation through Oxidative Stress and Induces Apoptosis in Prostate Cancer Cells

Essential oils (EOs) and their components have been reported to possess anticancer properties and to increase the sensitivity of cancer cells to chemotherapy. The aim of this work was to select EOs able to downregulate STAT3 signaling using Western blot and RT-PCR analyses. The molecular mechanism of anti-STAT3 activity was evaluated through spectrophotometric and fluorometric analyses, and the biological effect of STAT3 inhibition was analyzed by flow cytometry and wound healing assay. Herein, Pinus mugo EO (PMEO) is identified as an inhibitor of constitutive STAT3 phosphorylation in human prostate cancer cells, DU145. The down-modulation of the STAT3 signaling cascade decreased the expression of anti-proliferative as well as anti-apoptotic genes and proteins, leading to the inhibition of cell migration and apoptotic cell death. PMEO treatment induced a rapid drop in glutathione (GSH) levels and an increase in reactive oxygen species (ROS) concentration, resulting in mild oxidative stress. Pretreatment of cells with N-acetyl-cysteine (NAC), a cell-permeable ROS scavenger, reverted the inhibitory action of PMEO on STAT3 phosphorylation. Moreover, combination therapy revealed that PMEO treatment displayed synergism with cisplatin in inducing the cytotoxic effect. Overall, our data highlight the importance of STAT3 signaling in PMEO cytotoxic activity, as well as the possibility of developing adjuvant therapy or sensitizing cancer cells to conventional chemotherapy.