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This paper presents the first results about the provenance of obsidian fragments recovered in the archaeological site of Samshvilde (South Georgia, Caucasus) with the aim to obtain knowledge related to the network distribution and procurement of obsidian in Georgia. The geochemical characterization of thirty archaeological finds was obtained by the LA-ICP-MS method, an almost non-destructive technique capable of chemically characterizing the volcanic glass. A comparison of geochemical results obtained on both archaeological artefacts and geological samples collected from Chikiani outcrop in Georgia, together with literature data of southern Caucasus and eastern Turkey, allowed us to define the source of the archaeological obsidians of Samshvilde site. The majority of archaeological samples (28/30) shows a local provenance, precisely from Chikiani (Georgia) on the contrary the other two samples suggest a provenance from two different Armenian sources respectively Gegham and Akhurian volcanic system.

Syracuse and the other cities of the Hyblaean area (in south-eastern Sicily) are characterized by a close relationship between building stone and geological context, since the wide use of local calcarenites characterized and defined their urban planning and architecture. In this paper, we discuss the results of a research aimed at investigating four types of limestone used in the built heritage of Ortygia, the historic city centre of Syracuse (in south-eastern Sicily). Specifically, the following carbonate stones have been investigated: 1) Syracuse limestone and 2) Melilli limestone, from the Monti Climiti Fm., 3) Oolitic limestone from the Monte Carrubba Fm., and 4) Giuggiulena limestone from the Pleistocene Panchina. All lithotypes underwent several mineralogical-petrographic and physical-mechanical investigations to individuate the causes responsible for their different durability when placed in the outdoor environment. Results obtained were also compared with literature data concerning the other two limestones employed as building and decorative materials in the facades of historic buildings in Ortygia, precisely the “ Noto limestone” and the “Lumachelle limestone”, previously studied by other authors. Results achieved are consistent with deterioration types macroscopically observed in the monuments, and highlight the close relationship between compositional, textural, physical and mechanical characteristics of the stone and its specific damage.

The use of stone materials in cultural heritage and architecture represents a practice that has its roots in ancient times. Stone buildings, depending on the construction materials and their location in the urban context, are particularly vulnerable to weathering phenomena. These can be often accelerated by changes in environmental conditions linked mostly to the anthropic activities. In this way, the present work is addressed on the minero-petrographic and geochemical characterisation of samples taken from the built historical heritage in Cairo (Egypt), related to seven monumental areas. These sites have been chosen based on their historical importance, type of material, state of preservation and position in the Cairo context. The construction materials used and their degradation products were studied comparing the results obtained by means of different analytical techniques such as polarised light optical microscopy (POM), ion chromatography (IC), Fourier transform infrared spectroscopy (FT-IR) and the carbonaceous fraction, detected by using the thermogravimetry (TG). The results achieved demonstrated that black crusts and salt crystallisation represent the most common and damaging degradation products affecting all the monumental sites. Moreover, the environmental pollution produced by industrial activities and vehicular traffic has been identified as the main cause of these processes, followed by a marginal contribution of natural sources such as the sea spray. The data collected provide useful information to plan efficient conservation strategies in the future.

The consolidation and protection of mud bricks are a challenge in the field of conservation of archeological sites. One of the solutions is represented by the coverage of the entire excavation that assures a protection against mud dissolution. Unfortunately, this is not always feasible, both for economical and practical issues. For these reasons, alternative solutions are needed. In this work, laboratory experimentation has been carried out in order to test the efficacy of some products to slow down the dissolution process and increase the brick toughness. Three typologies of raw materials taken from different outcrops (one from the Republic of Azerbaijan and two from Calabria region, Italy) have been characterized and used to build mud brick specimens. Four consolidation treatments were tested (ethyl silicate, potassium silicate, potassium hydroxide, sodium hydroxide) and different investigations have been performed to check their efficiency against the dissolution in water. Results suggested that the efficacy of each treatment is related to the main intrinsic characteristics of the raw material employed for the mud bricks manufacture. Among the tested products, nanolime and NaOH solution showed very poor performance, while ethyl silicate and KOH could be very promising compounds for successful conservation.

In the present work, a variety of fragments of frescoes coming from the Villa dei Quintili in Rome (Italy) and dating back to the II century A.D. were subjected to, first of all, an X-ray fluorescence (XRF) analysis by optimizing a portable spectrometer for non-destructive investigation in the field of cultural heritage. The innovative aspect is the ability to obtain coloured maps referring to the distribution and concentration of elements present in the sample. Other than characterization, the aim was to improve the technique for non-invasive and fast in situ analysis. It has been performed, in conjunction with portable Raman analysis, at the ruins of the Villa dei Quintili on samples of different typologies including pottery, statues and frescoes, dating back to the II/III century A.D., different in colour, support and shape. From the results, the identification of the main pigmenting agents is attempted, providing the group of archaeologists in the villa with extremely valuable information for their work too. In particular, by comparing the XRF results for frescoes analysed in the laboratory, taken from the warehouse of the villa, and XRF and Raman data of frescoes analysed in situ, for which the provenance area inside the villa was known, the context of excavation and the manufacture process for some of the former has been hypothesized.

In the present work, two kinds of hybrid polymeric–inorganic coatings containing TiO2 or SiO2 particles and prepared starting from two commercial resins (Alpha®SI30 and Bluesil®BP9710) were developed and applied to two kinds of mortars (an air-hardening calcic lime mortar [ALM] and a natural hydraulic lime mortar [HLM]) to achieve better performances in terms of water repellence and consequently damage resistance. The two pure commercial resins were also applied for comparison purposes. Properties of the coated materials and their performance were studied using different techniques such as contact angle measurements, capillary absorption test, mercury intrusion porosimetry, surface free energy, colorimetric measurements and water vapour permeability tests. Tests were also performed to determine the weathering effects on both the commercial and the hybrid coatings in order to study their durability. Thus, exposures to UV radiation, to UV radiation/condensed water cycles and to a real polluted atmospheric environment have been performed. The effectiveness of the hybrid SiO2 based coating was demonstrated, especially in the case of the HLM mortar.

The consolidation of stone materials used in the Cultural Heritage represents a critical issue because of their restoration and conservation. In this regard, Yellow Neapolitan Tuff is not only one of the most used rock but also one of the most affected by degradation phenomena. For this reason, it needs to individuate suitable strategies to preserve efficaciously this material. The consolidant efficiency of innovative nano-silica products was tested in this paper to evaluate their possible use in the conservation of stones employed in Cultural Heritage. The mixtures realized with tuff fragments and consolidants as binder at different concentrations were undergone peeling and point load tests. The results achieved exhibit the suitability of nanosilica products as consolidant in the tuff, suggesting their possible next use in the preservation of stone materials employed in Cultural Heritage.

This paper presents the results of analyses carried out on the paintings on the rock-hewn walls of the Forty Martyrs church at Sahinefendi in Cappadocia (a UNESCO World Heritage Site), a central region of Turkey, performed during conservation work from 2007 to 2012. The micro-samples were investigated by spectroscopic, micro-stratigraphic and scanning electron microscopy analysis in order to study the painting technique, the materials and the degradation products. The micro-stratigraphic analysis showed a white, sometimes pinkish, plaster. Micro-Raman analysis, performed on cross-sections of the mortars, enabled the detection of calcite, gypsum, anhydrite and calcium oxalate. Scanning electron microscopy and energy-dispersive spectroscopy revealed a similar composition among all investigated phases, aside from minor differences such as the presence of diatoms in the second and third phases and of biotite, lime lumps and plants fragments in the fourth one. Apart from traditional pigments of medieval wall paintings, micro-Raman analysis revealed the presence of lead-based compounds and jarosite.

In this work, the complementary use of Fourier transform infrared (FT-IR) spectroscopy, conventional micro-Raman spectroscopy and UV-Raman scattering proved successful for the characterization of bulk minerals and of a variety of pigments from decorated finishing layers of plasters from a Roman archaeological site known as Villa dei Quintili , a monumental residence located in the south-eastern part of Rome (Italy). The used multi-technique approach provided insights on the pictorial technique, giving information that could be useful for proper restoration. It is worth underlining that the present study represents the first attempt of carrying out UV resonance Raman measurements for analysing cultural heritage materials.

In the absence of an apoptotic signal, BAX adopts a conformation that constrains the protein from integrating into mitochondrial membranes. Here, we show that caspases, including caspase-8, can initiate BAX insertion into mitochondria in vivo and in vitro. The cleavage product of caspase-8, tBID, induced insertion of BAX into mitochondria in vivo, and reconstitution in vitro showed that tBID, either directly or indirectly, relieved inhibition of the BAX transmembrane signal-anchor by the NH2-terminal domain, resulting in integration of BAX into mitochondrial membrane. In contrast to these findings, however, Bid-null mouse embryo fibroblasts supported Bax insertion into mitochondria in response to death signaling by either TNFalpha or E1A, despite the fact that cytochrome c release from the organelle was inhibited. We conclude, therefore, that a parallel Bid-independent pathway exists in these cells for mitochondrial insertion of Bax and that, in the absence of Bid, cytochrome c release can be uncoupled from Bax membrane insertion.