Ioana Gomoiu

The effect of spaceflight on growth of Ulocladium chartarum colonies on the international space station.

The objectives of this 14 days experiment were to investigate the effect of spaceflight on the growth of Ulocladium chartarum, to study the viability of the aerial and submerged mycelium and to put in evidence changes at the cellular level. U. chartarum was chosen for the spaceflight experiment because it is well known to be involved in biodeterioration of organic and inorganic substrates covered with organic deposits and expected to be a possible contaminant in Spaceships. Colonies grown on the International Space Station (ISS) and on Earth were analysed post-flight. This study clearly indicates that U. chartarum is able to grow under spaceflight conditions developing, as a response, a complex colony morphotype never mentioned previously. We observed that spaceflight reduced the rate of growth of aerial mycelium, but stimulated the growth of submerged mycelium and of new microcolonies. In Spaceships and Space Stations U. chartarum and other fungal species could find a favourable environment to grow invasively unnoticed in the depth of surfaces containing very small amount of substrate, posing a risk factor for biodegradation of structural components, as well as a direct threat for crew health. The colony growth cycle of U. chartarum provides a useful eukaryotic system for the study of fungal growth under spaceflight conditions.

Analysis of Historical Monuments Through the Lens and Electrons: Case Study: The Monastery Hurezi

The Horezu Monastery is dating from the seventeenth century, but the refectory was built in the western side of its axis and painted in the early eighteenth centuries. The main objective of the work is to perform a deep analysis of pink and black pigmentation from the refectory and the cellar. It started from the pink coloration observed by the naked eye followed by photographic registration and analysis by mobile optical microscope. Then micro samples have been taken for analysis at optical and electronic microscope and resin embedding to obtain cross-sections. Photographic registration is a useful method to map pink pigmentation but microscopy and microbiological analysis are essential for finding its biological origin. Spherical cells like Rubrobacter grouped in chains or tetrads developing a pink biofilm and filamentous branching bacteria like actinomyces were identified on the surface of mortar, mural painting and bricks. Many groups of bacteria have been found in cracks and pores. This observation explains the ability of pink bacteria to travel through pores and clog them impairing water evaporation. Black pigmentation is the result of mortar colonization by fungi which developed both mycelium and conidiophores with conidia. Examination of the samples by lens and electrons allows scientists and restorers to identify the microbiological origin of the pink and black discoloration and to avoid their misinterpretation as colors which are coming from chemical reactions or deposits from the atmosphere. Based on these results, a strategy for decontamination is elaborated to be applied before restoration work.