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Acoustic emission is a well-known noninvasive methodology for the study of defects in materials but still rarely applied in the field of cultural heritage diagnostic. How alteration products and degradation processes affect the acoustic emission signal still is an open issue. The proposed study concerns the utilization of such techniques to investigate the relations existing between the moisture content and the typology and amount of crystallized salts with the acoustic emission features. This work focuses on spruce wood logs belonging to an historical warehouse in Trondheim, Norway, since no strictly scientific studies exist on the conservation conditions of these big wooden structures. The methodology, also involving the moisture content measurement of structures and the samplings of portions analyzed through vacuum microbalance, allowed identifying a clear relationship between the amount of water in logs as a function of their distance from the ground and variations in the amplitude of the acoustic emission signals.

The structures of three bacterial outer membrane proteins (OmpA, OmpX and PagP) have been determined by both X-ray diffraction and NMR. We have used multiple (7 x 15 ns) MD simulations to compare the conformational dynamics resulting from the X-ray versus the NMR structures, each protein being simulated in a lipid (DMPC) bilayer. Conformational drift was assessed via calculation of the root mean square deviation as a function of time. On this basis the 'quality' of the starting structure seems mainly to influence the simulation stability of the transmembrane beta-barrel domain. Root mean square fluctuations were used to compare simulation mobility as a function of residue number. The resultant residue mobility profiles were qualitatively similar for the corresponding X-ray and NMR structure-based simulations. However, all three proteins were generally more mobile in the NMR-based than in the X-ray simulations. Principal components analysis was used to identify the dominant motions within each simulation. The first two eigenvectors (which account for >50% of the protein motion) reveal that such motions are concentrated in the extracellular loops and, in the case of PagP, in the N-terminal alpha-helix. Residue profiles of the magnitude of motions corresponding to the first two eigenvectors are similar for the corresponding X-ray and NMR simulations, but the directions of these motions correlate poorly reflecting incomplete sampling on a approximately 10 ns timescale.