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The Italian seed bank network (RIBES) aims to improve the quality and safety of the germplasm reserves of native plant species in Italy to ensure the long-term conservation of endangered and/or endemic flora. The strategy includes traditional methods to secure seed conservation. A comprehensive priority list for seed collection is being defined, it was prepared by crossing data of various checklists (red lists, endemics) and will soon be cross-referenced with an updated list of accessions of the whole network. A safety-backup program of duplicates will quickly be implemented to secure the conservation of the most threatened species in at least two seed banks of the network. On the other hand, the RIBES strategy also includes research by applying modern techniques. In collaboration with the Millennium Seed Bank, research on the storage behaviour of seeds and spores through thermal analysis is ongoing to inform conservation. Using the Differential Scanning Calorimetry (DSC), we could evaluate seed lipid properties such as glass transition temperature, melting, crystallization, oxidation behaviour, and thermal stability. Finally, RIBES participates as a co-funder in the LIFE Nature project SEEDFORCE, coordinating 11 seed banks of the network for collecting seeds/spores of 29 threatened species of EU interest. [ABSTRACT FROM AUTHOR]

Abstract: The 5th April 2003 paroxysmal event was the strongest explosion that has occurred at Stromboli in the last 50 years. This event lasted only few minutes and was characterised by two violent explosions, followed by gas and pyroclast emission. In order to constrain models of the dynamics of the paroxystic event the viscosity of anhydrous and hydrous Stromboli high potassium (HK)-basaltic melts have been measured. Viscosity has been investigated in the low viscosity range with the falling sphere method at superliquidus temperatures (1423 to 1673 K) and 0.5 GPa and in the high viscosity range with micropenetration near the glass transition temperature (723 to 1035 K) at atmospheric pressure. Falling sphere experiments were performed in a piston cylinder apparatus with melts whose water content varies from nominally anhydrous (0.02 wt.% H2O) to 4.16 wt.% H2O. The combination of high- and low-viscosity data permits a general description of the viscosity as a function of temperature and water contentusing a modified Tamman–Vogel–Fulcher equation. Using these new viscosity data, an estimation of the flow regime and magma velocity is performed. Our data suggest that the ascent of magma from the 7–8 km deep reservoir to a shallower reservoir located at about 3 km of depth, may occur within minutes. Moreover, we infer a turbulent flow regime. Finally, our estimates of the ascent velocity agree qualitatively with results from petrological studies (e.g. [Bertagnini, A., Métrich, N., Landi, P., Rosi, M., 2003. Stromboli volcano (Aeolian Archipelago, Italy): an open window on the deep-feeding system of a steady state basaltic volcano. Journal of Geophysical Research 108, 2336–2350.]), which indicate a turbulent flow regime and rapid ascent velocities such to inhibit volatile-loss-induced crystallization. We conclude that hazard evaluation at Stromboli Island should incorporate the likelihood of very rapid ascent of less-evolved melts from depth. [Copyright &y& Elsevier]

The aim of this study is to carry out investigations in order to establish the composition and technological behaviour of the Roman glass dated from IV to VI c. For this reason the glass transition temperature (Tg) at 380 °C, the softening point at 490 °C and crystallization ability were determined. The fragment has been investigated by a classical chemical analysis, an electron probe microanalysis, differential thermal analysis, infrared spectroscopy, transmission electron microscopy and X-ray diffraction. According to the chemical composition, the fragment is soda-lime–silica glass that is typical for the production of this region. Microheterogeneities were found which are originated from the preparation method and from the corrosion caused by soil influence. As a result of additional thermal treatment the crystal phases were also established. [Copyright &y& Elsevier]

Relaxation geospeedometry using differential scanning calorimetry (DSC) has been applied to quantify the cooling history across the glass transition of flow ramps at the front of the calcalkaline rhyolite Rocche Rosse flow of Lipari, Aeolian Islands, Italy. Modelled cooling rates for the obsidian retrieved from two profiles range between 0.2 and 0.03 K min[sup -1]. Cooling at the flow front appears to be dominated by conductive heat loss of individual flow ramps forming individual cooling units. Cooling rates of tens of Kelvins per day appear to have controlled the last stage of viscous deformation before the entire flow came to rest. It is inferred that cooling rates slower than those modelled are required to sustain flow in highly viscous rhyolitic lavas. [ABSTRACT FROM AUTHOR]

Provides an overview of the papers included in the 2002 special issue of the 'Philosophical Magazine' which covered the fields of the glass transition, the dynamics of disordered systems and photonic. Presentation of the papers at the Eight International Workshop on Disordered Systems in Andalo, Italy; Number of oral and poster contributions.'