{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,29]],"date-time":"2025-12-29T11:47:49Z","timestamp":1767008869456,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,11]],"date-time":"2023-01-11T00:00:00Z","timestamp":1673395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"H2020 Laserlab Europe","award":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"],"award-info":[{"award-number":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"]}]},{"name":"H2020 FETOPEN project \u201cDynamic\u201d","award":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"],"award-info":[{"award-number":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"]}]},{"name":"NSRF 2014\u20132020 \u201cBIOIMAGING-GR\u201d","award":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"],"award-info":[{"award-number":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"]}]},{"name":"\u201cINNOVAPROTECT\u201d","award":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"],"award-info":[{"award-number":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"]}]},{"name":"Greece and the European Union (European Regional Development Fund)","award":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"],"award-info":[{"award-number":["EC-GA 871124","EC-GA-863203","MIS 5002755","MIS 5030524"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Photoacoustic (PA) imaging is a novel, powerful diagnostic technique utilized in different research fields. In particular, during recent years it has found several applications in Cultural Heritage (CH) diagnostics. PA imaging can be realized in transmittance or epi-illumination (reflectance) modes, obtaining variable levels of contrast and spatial resolution. In this work, we confirmed the applicability of the PA technique as a powerful tool for the imaging of one of the most challenging artwork objects, namely fresco wall paints, to obtain precise stratigraphic profiles in different layered fresco samples. In this regard, we studied some multi-layered fragments of the vault of San Giuseppe Church in Cagliari (1870 AD) and some mock-ups realized specifically to test the potentiality of this technique. Due to complex structures of the frescoes, we used the Spatially Off-set Raman Spectroscopy (SORS) technique to provide complementary information. The experimental results were in agreement for both techniques, even for the three-layered complex structure, and were confirmed with Scanning Electron Microscopy (SEM) analysis of cross-sections. The combined use of these two techniques proved useful to investigate detailed hidden information on the fresco samples.<\/jats:p>","DOI":"10.3390\/jimaging9010016","type":"journal-article","created":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T02:28:44Z","timestamp":1673490524000},"page":"16","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Stratigraphy of Fresco Paintings: A New Approach with Photoacoustic and SORS Imaging"],"prefix":"10.3390","volume":"9","author":[{"given":"Francesca A.","family":"Pisu","sequence":"first","affiliation":[{"name":"Department of Physics University of Cagliari, Cittadella Universitaria, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2097-1229","authenticated-orcid":false,"given":"Daniele","family":"Chiriu","sequence":"additional","affiliation":[{"name":"Department of Physics University of Cagliari, Cittadella Universitaria, 09042 Monserrato, CA, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Evgenia","family":"Klironomou","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, 70013 Heraklion, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giannis","family":"Zacharakis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, 70013 Heraklion, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-3472","authenticated-orcid":false,"given":"George J.","family":"Tserevelakis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, 70013 Heraklion, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2540","DOI":"10.1364\/BOE.2.002540","article-title":"In vivo three-dimensional spectroscopic photoacoustic imaging for monitoring nanoparticle delivery","volume":"2","author":"Kim","year":"2011","journal-title":"Biomed. Opt. 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