A multi-parametric investigation on waterlogged wood using a magnetic resonance imaging clinical scanner

In cultural heritage conservation science, moisture content (MC) is an essential factor to determine. At the same time, it is essential to choose non-destructive and non-invasive approaches for more sustainable investigations and make them safe for the environment and the sample. The question addressed in this work concerns the possibility and the opportunity to investigate waterlogged wood by using nuclear magnetic resonance imaging (MRI) clinical scanners to carry out non-destructive volumetric diagnostics. In this study, MRI, the most important non-invasive medical imaging technique for human tissue analysis, was applied to study archaeological waterlogged wood samples. This type of archaeological material has a very high moisture content (400%–800%), thus, it is an ideal investigative subject for MRI which detects water molecules inside matter. By following this methodology, it was possible to obtain information about water content and conservation status through a T1, T2, and T2* weighted image analysis, without any sampling or handling, and the samples were directly scanned in the water where they were stored. Furthermore, it permited processing 3D reconstruction, which could be an innovative tool for the digitalization of marine archaeological collections. In this work, 16 modern species of wood and a waterlogged archaeological wood sample were studied and investigated using a clinical NMR scanner operating at 3T. The results were compared with X-ray computed tomography (CT) images, as they had already been used for dendrochronology. The comparison highlights the similar, different, and complementary information about moisture content and conservation status in an all-in-one methodology obtainable from both MRI and CT techniques

Effect of age on Pine wood microstructure studied by micro-MRI and diffusion-NMR

Wood is a natural complex material widely used from men in the past to create artworks. One of its main anatomical elements is the annual ring that varies according to the species, the weather conditions under which the tree has grown and to possible adversities. To observe the anatomy of waterlogged archaeological wood could be complicated because of its degradation. However, knowing the state of conservation is very important for the future restoration. In this work a non-destructive approach based on the combined use of MRI and diffusion on the modern and ancient pine wood is presented. Micro-MR images allow to observe the diagnostic features. The molecular NMR diffusion analysis, with the estimation of the pores diameter and the tortuosity, provide important information about the effect of age on the wood microstructure. At the end of the analysis the unaltered sample can be repositioned in its original location on the artwork

Linear cutting trepanation in Italy: a unique case from Hellenistic Sicily (3rd century BC)

During the archaeological excavations conducted in the Hellenistic necropolis discovered in Messina (Sicily, Italy) dating back to the 3rd century BC., a skeleton showing evidence of cranial traumas and surgical intervention was found. The skull, belonging to a young adult male, presented signs of four head injuries produced by both blunt and sharp-edged instruments. The first two lesions, located on the frontal bone, were produced by blunt blows and showed signs of long-time survival. The third lesion, located on the inferior portion of the right parietal, suggests a perimortem non-penetrating linear cut probably caused by a blade instrument. Finally, a rectangular bone loss is visible on the left parietal bone, involving the full cranial thickness with well-delimited cutting-edges and no sign of a reparative process. This injury can be interpreted as the result of a trepanation, performed with the technique defined as "linear cutting" and obtained through four linear incisions in parallel pairs intersecting at the right angles. The trepanation is probably related to the multiple head injuries exhibited by the patient, who unfortunately did not survive the surgical intervention. Trepanation in Italy has been largely attested since Prehistoric times, but the case from Messina represents the first evidence of neurosurgical intervention performed through the linear cutting technique in the Italian context and the second case in the whole of Europe. This technique might have been imported in Sicily during the Hellenistic period from the Near East, where it is clearly attested

Discrimination between softwood and hardwood based on hemicellulose content obtained with portable nuclear magnetic resonance

Wood is a hygroscopic material that can reach an equilibrium moisture content when ambient temperature and relative humidity are constant. Moisture affects all properties of wood, as well as its preservative treatment. The hygroscopic behavior of wood can be attributed to the hydroxyl groups of its constituents. Since hemicellulose shows the greatest water affinity, it can be considered the main responsible for the ingress of water into the wood mass. Below the fiber saturation point, wood moisture is only stored in the cell walls. Proton Nuclear Magnetic Resonance (NMR) is a relative method used for the evaluation of moisture content distribution in wood and NMR relaxation is an excellent tool to study the hygroscopic behavior of different woods below the fiber saturation point. This work aimed to test the hypothesis of discriminating among softwoods and hardwoods of different botanical species and identifying further sub-clusters of woods based on the NMR proton spin–spin ( T 2 ) and spin–lattice ( T 1 ) relaxation times of their cell wall water in the hygroscopic moisture range. Importantly, the study was performed using a portable low-cost NMR instrument with which it is possible to investigate wood samples of any size. The main result of this study was that at RH = 94% the relaxation time T 2,2 , associated with the cell wall bound water, can be used as a marker to discriminate among softwoods and hardwoods

A Multi-Parametric Investigation on Waterlogged Wood Using a Magnetic Resonance Imaging Clinical Scanner

In cultural heritage conservation science, moisture content (MC) is an essential factor to determine. At the same time, it is essential to choose non-destructive and non-invasive approaches for more sustainable investigations and make them safe for the environment and the sample. The question addressed in this work concerns the possibility and the opportunity to investigate waterlogged wood by using nuclear magnetic resonance imaging (MRI) clinical scanners to carry out non-destructive volumetric diagnostics. In this study, MRI, the most important non-invasive medical imaging technique for human tissue analysis, was applied to study archaeological waterlogged wood samples. This type of archaeological material has a very high moisture content (400%–800%), thus, it is an ideal investigative subject for MRI which detects water molecules inside matter. By following this methodology, it was possible to obtain information about water content and conservation status through a T1, T2, and T2* weighted image analysis, without any sampling or handling, and the samples were directly scanned in the water where they were stored. Furthermore, it permited processing 3D reconstruction, which could be an innovative tool for the digitalization of marine archaeological collections. In this work, 16 modern species of wood and a waterlogged archaeological wood sample were studied and investigated using a clinical NMR scanner operating at 3T. The results were compared with X-ray computed tomography (CT) images, as they had already been used for dendrochronology. The comparison highlights the similar, different, and complementary information about moisture content and conservation status in an all-in-one methodology obtainable from both MRI and CT techniques