Structural changes of tissue samples exposed to low frequency electromagnetic field: A FT-IR absorbance study

In the present work, we report on a preliminary Fourier Transform Infrared (FT-IR) Absorbance study performed on different kind of rat tissues, such as kidney and heart, exposed to a "non-ionizing" radiation source at low frequency, in the range typical of micro-waves (300 MHz <v< 300 GHz). The data were collected in a wide wavenumber region, from 400 cm−1to 4000 cm−1. The comparison of the absorbance spectra in the case of the normal tissues with the irradiated ones has shown significant differences in the spectral features in accordance with the morphological analysis performed by the optical microscopy

Diagnostic investigation of the Cycle of the new church of Sarria (Floriana, Malta) by Mattia Preti

In the present paper, we present the main results of a diagnostic investigation on different paintings by Mattia Preti, belonging to the Cycle of the New Church of Sarria, located inside the Church of the Immaculate Conception of Sarria (Floriana) in Malta. The analysis was carried out on the occasion of the restoration process and, due to the short time available, only on some representative areas of each painting. A multi-technique approach was applied in situ, employing X-ray fluorescence spectroscopy (XRF) and Raman microscopy. The aim was to achieve information on the execution technique, in a completely non-invasive way, following the requirements of the restorers.peer-reviewe

New insights to assess the consolidation of stone materials used in built heritage: the case study of ancient graffiti (Tituli Picti) in the archaeological site of Pompeii

Abstract Tituli Picti are an ancient form of urban graffiti very common in the archaeological site of Pompeii (Naples, South—Italy). They are generally made of red pigments applied on walls of Campanian ignimbrite. This paper deals with a scientific investigation aimed to their conservation. This is a challenging task since it requires a multidisciplinary approach that includes restorers, archaeologists and conservation scientists. The study has provided suggestions on the proper way to conserve Tituli Picti over time. In the present work, several specimens of Campanian ignimbrite were painted with red earth pigment; lime and Arabic gum have been used as binders as well. Such painted stones were treated with three consolidants: a suspension of reactive nanoparticles of silica, ethyl silicate and an acrylic microemulsion. Treated and untreated specimens were subjected to thermal aging, artificial solar radiation and induced crystallization decay. It has been assessed the colorimetric variations induced by treatments. Moreover, the micromorphologic features of the consolidated surfaces have been highlighted by means of electron microscope observations. The scotch tape test allowed to compare the superficial cohesion induced by the three used products. According to the results, ethyl silicate seems to represent the most successful product

Scientific investigation of The Conversion of St Paul painting (Mdina, Malta)

The paper presents the results of two different approaches applied to the newly-restored painting The Conversion of St Paul, the main altarpiece in the Cathedral of Mdina in Malta. This large, dramatic painting is work of the Baroque artist Mattia Preti, il Cavaliere Calabrese. As is normal with a professionally executed restoration, several scientific methods have been used before, during and at completion, in the framework of a global analytical strategy. In particular, we focus on the results of the digital photogrammetric survey which uses image-based approaches for 2D/3D models reconstruction enormously. The model was used to quantify and measure important features on the painting as well extensions of areas restored. In addition, portable Raman spectroscopy was used to identify, in non-destructive way, the nature of the painting materials with the final goal of reconstructing the color palette of the artist.peer-reviewe

Digital reconstruction and scientific analysis prior the restoration of two paintings by Mattia Preti in the Church of the Immaculate Conception of Sarria (Floriana, Malta)

The paper presents the results of scientific investigations carried out in support of a professionally executed restoration on two paintings by Mattia Preti, located in the Church of the Immaculate Conception of Sarria in Floriana, Malta. In particular, the attention was mainly paid on a combined approach, using 2D/3D survey in order to formulate hypothetic reconstruction, and XRF spectroscopy in order to get more information on how the master prepared the various types of materials, with particular regard to the painting preparation, the pigments palette and the formulation of shades and highlights.peer-reviewe