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This work explores the potential of self-powered MEMS devices for application in the preventive conservation of cultural heritage. The main objective is to evaluate the effectiveness of piezoelectric aluminum nitride MEMS (AlN-MEMS) for monitoring vibrations and to investigate its potential for harvesting energy from vibrations, including those induced by visitors. A preliminary laboratory comparison was conducted between AlN-MEMS and the commercial device Tromino®. The study was then extended to the Picture Gallery of Ursino Castle, where joint measurements with the two devices were carried out. The analysis focused on identifying natural frequencies and vibrational energy levels by key metrics, including spectral peaks and the Power Spectral Density (PSD). The results indicated that the response of the AlN-MEMS aligned well with the data collected by the commercial device, especially observing high vibrational energy around 100 Hz. Such results validate the potential of AlN-MEMS for effective vibration measurement and for converting kinetic energy into electrical power, thereby eliminating the need for external power sources. Additionally, the vibrational analysis highlighted specific locations, such as the measurement point Cu4, as exhibiting the highest vibrational energy levels. These points could be used for placing MEMS sensors to ensure efficient vibration monitoring and energy harvesting. [ABSTRACT FROM AUTHOR]

In the study of archaeological ceramics, it is important to have compositional data to identify their origin and source. The fabric also provides useful information on the production technology, especially with regard to the firing steps. The work presented here is connected to this field and focuses on the main parameters related to the terracotta artefacts preparation. Thus, one can consider the effects in terracotta characteristics of different raw materials and firing parameters, in particular for pottery of Caltagirone, which is one of most important centres of pottery production in Italy, active since the Neolithic. To this end, terracotta samples have been reproduced in a laboratory setting according to the ancient procedure of Caltagirone manufacture, starting from clay and degreaser extraction in local historical sites. The analysis was conducted using a portable X-Ray Fluorescence (pXRF) spectrometer for elemental characterization of sand degreaser and of clays during each step of the realization process and in different firing conditions. SEM-ED techniques were also employed to verify the method and results for some of the samples after firing process. Framing the technological context of manufacture production, known in the specific case, it is also possible to identify potential outcomes and limits in the study of potsherds using pXRF technology, in applying the methodology to historic artefacts.

Glass is found at archeological excavations in a variety of conditions ranging from pristine—where no deterioration is visible—to very heavily degraded. Although the chemical processes of glass deterioration have been extensively studied, they are not yet entirely understood, due in part to the numerous factors that must be considered, from the composition of the glass paste and its manufacture to the type of soil in which the glass is buried. In this study, we analyze an assemblage of Late Roman glass from the catacombs of Saint Lucy in eastern Sicily, in order to study the effects of this particular hypogeal environment on glass. The study regards the correlation between the weathered glass surfaces and the compositional changes occurred in the samples. Close attention is paid to optical observations of the outer layers of the glasses as manifestations of chemical deterioration of the bulk. The chemical analysis of the fragments of glass was carried out nondestructively using PIXE‐PIGE analyses without any sample preparation. Weathering was observed with an optical microscope. [ABSTRACT FROM AUTHOR]

Sampling represents an important step of the procedure to perform authenticity tests by ThermoLuminescence (TL). The result of the test could be compromised if this phase is not correctly carried out. During the drilling, in fact, a local temperature increasing could cause a loss of the luminescence signal. In this paper, the comparison between IR thermography imaging and electrical measurements is shown also in order to validate a specific conceived model. The research is aimed at implementing the procedure used to perform the TL tests with the measurement of the temperature reached during the drilling. The measurements were performed using a pottery sherd simulating the collection step. Results show the validity of the model and provide data useful to optimize the sampling in TL test methodology. [ABSTRACT FROM AUTHOR]

During the restoration works of the Sant'Agata La Vetere church in Catania, a campaign of archaelogical excavations was conducted in order to study the complex site around the religious building. According to tradition and to historical sources, the site was very interesting because a part of the church, in particular the crypt, was built incorporating an apse of the roman praetorium palace. Starting from this assumption, the present study is focused on the resolution of the chronological question about the different construction phases of the crypt. In agreement with archaeologists and architects, samples of bricks are collected in specific area. The ThermoLuminescence (TL) methodology was applied performing measurements on polymineral fine grain phases extracted from each brick. The Equivalent Dose (ED) values were evaluated from TL signals through Added Dose procedure. The annual Dose Rate (DR) was calculated using the radioactive content of samples estimated by ICP-MS analysis and environmental and cosmic dose rates obtained by in situ gamma measurements. From the obtained ages, three phases of construction were individuated: 3rd, 7th-8th and 17th centuries. In particular, the first one could be correspond with the end of the roman period, and it seems to confirm the archaeological hypothesis based on the historical sources. From a methodological point of view, the archaeological issue contributed to study the behaviour vs time of the alpha efficiency coefficient k. The results showed that the value obtained after 30 days has to be considered. [ABSTRACT FROM AUTHOR]

The aim of this work is to verify the potential use of GAFchromic TM EBT3 and FILMQA TM pro software for patient specific quality assurance (QA) for stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT) treatment plans in clinical routine use. In particular, encephalic, pulmonary and lymph node treatments plans were selected for this study. The agreement between the calculated and measured dose distributions were evaluated in terms of ɣ index with 3%3mm, 2%2mm, 1.5%1.5mm and 3%1.5mm criteria. The obtained results were then compared to the routine pre-treatment verification method which uses electronic portal imaging device (EPID) and EPIQA analysis software. EBT3-FilmQA method results show a mean ɣ index passing rate >95% with 2%1.5mm analysis criteria and an improvement of about 7% compared with EPID-EPIQA method results., (© 2022 Old City Publishing, Inc.)