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A multi-analytical approach was employed for the first time to study the stone materials, wall paintings and related degradation forms in the Cathedral of Gerace (Reggio Calabria, southern Italy). With an area of around 1898 square meters, the Gerace Cathedral is the largest in Calabria: its construction dates back to the Norman era (between 1085 and 1120), and currently displays distinct features of Greek and Latin architectural orders. Despite having undergone numerous restorations, the church perfectly preserves its original buildings materials. Following an extensive site inspection campaign, supported by the experts dealing with building restoration, several areas were selected for analyses. Both in situ investigations and laboratory tests were carried out on micro-fragments using Non-Destructive and Micro-Destructive Techniques (NDTs and MDTs). The first step involved an inspection through InfraRed Thermography (IRT) in order to map the internal walls of the Cathedral and identify zones with potential degradation phenomena. Subsequently, a more in-depth study was designed based on the thermographic results, and laboratory tests were carried out on micro-fragments and powders to characterize the different kinds of materials (i.e., stones, mortars, plasters and pigments) and decay agents (i.e., salts and efflorescences). Thirty-one samples were subjected to a complementary analytical approach which included Polarizing Optical Microscopy (POM), Ion Chromatography (IC), X-Ray Powder Diffraction (XRPD) and Scanning Electron Microscopy (SEM) coupled with microanalysis (EDS). The results allowed us to preliminarily characterize the different materials from which the Cathedral was built, determine its state of conservation and provide a better knowledge of the entire building, revealing details not visible to the naked eye which are important for future conservation interventions. As for the state of conservation, the integrated use of various techniques enabled the detection of rising damp generally correlated with the occurrence of water infiltration and migration phenomena which appear to affect a large part of the building, causing noticeable damage (i.e., loss of surface material, micro-cracks, white salt efflorescence, etc.). The characterization of the materials carried out on mortars, plasters, and pigments also confirmed the local origin of the raw materials. However, the provenance of the studied marbles and crystalline limestones, could not be established and, therefore, further in-depth studies are required.

In the last decades there have been several studies on cultural heritage regarding the performance of protective and consolidating coatings for the prevention of decay. A coating must have several characteristics such as: efficiency, breathability, and must be durable and reversible. In this research work we tried to verify the performance of a commercial protective product such as Fosbuild FBLE 200, which is composed of a TiO2 nanopowder dispersed in an aqueous solution of an acrylic polymer. This product, which exhibits depolluting, antimicrobial, water-repellent and self-cleaning characteristics, has been applied on different lithotypes such as: Carrara marble, Noto and Comiso stone and exhibited in two different outdoor environments such as Catania and Palermo. These two cities are mostly affected by pollution produced by vehicular traffic; moreover, Catania is also affected by pollution produced by the activity of Mount Etna.

The purpose of this study is to demonstrate how a disciplinary approach is an excellent tool in the field of forensic investigations, capable of answering the questions posed by the institution and obtaining as different and as much information as possible on the findings analyzed, reconstructing the history of often decontextualized artifacts. In the present work, the results of the FTIR-ATR and SEM-EDX analyses performed on micro-fragments and powders taken from a marble bas-relief, seized by the Cosenza Carabinieri Unit for the Protection of Cultural Heritage and Anti-Counterfeiting (Calabria, Italy), are reported.

This paper deals with the formulation of innovative mortars for the consolidation of archeological structures in underwater environment. The research was conducted within the frame of the MaTaCoS project (Advanced materials and technologies applied to the conservation of underwater cultural heritage) funded by MISE (Italian Ministry of Economic Development). The project concerns the design of advanced tools and methods for the protection of Underwater Cultural Heritage, through specific cleaning and consolidating procedures to be applied directly in situ. The fishpond of the archaeological site of Castrum Novum (Santa Marinella, Rome, Italy) was chosen as a pilot site for experimentation. It is a structure on the coastline, composed of only one tank, with an average immersion of 0.37 m below the sea level, and developing with an NE/SW orientation. The masonry structures reach the maximum thickness at the apex of the fishpond (4.70 m) and consist of a concrete conglomerate composed of slightly rough stones of medium size bound with non-hydraulic mortar. Selected mortars' fragments taken from the fishpond were characterized by means of minero-petrographic technique in order to define their main constituents from a compositional and textural point of view and also to identify the various degradation processes, mainly biological colonization. Starting from the acquired information, innovative mortars were formulated with the addition of two different anti-fouling additives aimed to slow down the above-mentioned degradation. The efficacy of the anti-fouling products was tested on specimens settled in laboratory environment (artificial marine environment). This information could be useful both for the definition of restoration interventions and for planning preservation protocols to be applied in this peculiar environment.

The possibility to use ultrasonic nondestructive testing for the diagnosis and characterization of decay in building materials due to salts crystallization is here investigated. Salts crystallization is one of the main sources of decay for stone materials, especially for cultural heritage items underwater or exposed to water, and its early detection as well as a continuous monitoring is highly desirable. Currently, this often requires the use of destructive methods and the sampling of the items under inspection. This work shows promises to the successful use for this purpose of ultrasonic nondestructive testing.

The contribution shows the first results of ongoing research on the origins and prehistoric assumptions of the well-known Etruscan and Roman harbour of Pyrgi, an ancient Ceretan harbour in southern Etruria. In the light of recent land and submarine investigations, traces of ancient frequentations and contacts dating back to the Neolithic era are emerging when the coastal morphology and environmental characteristics of the site were very different from the current ones. The Etruscan port of Pyrgi, which continues its historical history in Roman and Medieval times, appears as the heir of one or more landing points frequented perhaps already in the Middle Neolithic. As part of this contribution, around 60 obsidian finds (waste resulting from the manufacture of arrowheads) were analyzed using the LA-ICP-MS technique (Laser Ablation Inductively Coupled Plasma Mass Spectrometry). The comparison between the data obtained on the archaeological finds and the bibliographic data relating to the geological obsidians of the peri-Tyrrhenian area allowed the identification of the provenance of the finds. In particular, most of the finds can be attributed to the Aeolian area, highlighting the leading role played by the Aeolian archipelago in the development of trade of this material. Other sources of supply have been identified on the island of Palmarola and in Sardinia (Monte Arci) although with a lower incidence. The discovery of numerous findings in obsidian from overseas, which took place in the area immediately surrounding Pyrgi, offers different suggestions about the origin of the docking place, with traces of centuries-old frequentation, extended from the Neolithic to the modern era.

Black crusts are typical decay forms on calcareous rocks in polluted urban environments. Their origin is due to “sulphation” reaction of calcium carbonate substrates (CaCO3), as a consequence of pH value decrease caused by SO2 in the polluted atmosphere. They can be therefore defined as a passive air pollution sampler. For the purpose of this work, samples from the historic center of Venice were analyzed. The city of Venice suffers in particular maritime and industrial pollution (Marghera industrial zone). By means of minero-petrographic and geochemical analyses, it was possible to obtain information on the mineralogy of the crust and its interaction with the underlying substrates, other than useful information on the chemical composition in terms of major and traces elements linked to the various sources of urban pollution.

In this work we reconstructed the major climatic changes occurred since the last postglacial transition to the Holocene in SW Calabria (southern Italy). We applied a multidisciplinary approach based on both marine and continental paleoclimatic and paleoenvironmental proxies. In particular, we focused (i) on the effects of eustatic sea-level rise on the submerged continental shelf (interpreted through offshore seismic and core stratigraphy, along with paleoecological and palynological analyses), and (ii) on the geomorphic consequences on land of the main climatic changes and their interplay with late prehistoric to historic human activities (deforestation, cultivation, ploughing, etc.), recorded by soil features in archaeological contexts and pollens in marine cores. In particular, the transgressive and highstand systems tracts that overly the Last Glacial Maximum unconformity surface were reconstructed in detail. They indicate an upward deepening of sedimentary environments followed by overall depth stability, also confirmed by mollusc paleobiocoenoses. Geomorphic stability coupled with warm and humid climate characterized the middle Holocene, promoting major soil development during Neolithic times. Important changes in soil features towards the late Holocene point to a phase of climatic drying and land degradation (probably during the Bronze age, ~4 ka BP), followed by restored prolonged moisture availability alternated with minor warm or dry events. Different episodes of intense soil erosion and human impact occurred in this period, with increasing deforestation and cultivation during about the last 2 ka, as testified by soil features and pollen stratigraphy. The consequent marine response can be probably related to seaward progradation of the late Holocene sedimentary units, also reflecting river systems adjustment to eustatic base-level rise and highstand.

In Mediterranean area there are several olive oil mills and tanning plants producing a large amount of wastewaters rich of phenolic compounds. Our research group is aimed to identify microalgae species with extracellular phenoloxidase activity to use them in wastewaters phycoremediation. In order to achieve our goal, we have started a screening of a microalgae collection available at the University of Naples (Department of Biological Science). So far, one hundred microalgae strains have been tested for enzymatic extracellular activity in the presence of: 2,2-azino-bis 3-ethybenzthiazoline- 6-sulfonic acid (ABTS); Remazol Brilliant Blue R (RBBR); syringaldazine; 2,6-dimethoxyphenol (2,6- DMP). Among them, two strains have shown promising results for phenols degradations.

Phytoremediation deals with the use of plants, or other green photosynthetic organisms, to reduce organic or inorganic pollutant in the environment, mainly waters and soils (Pivetz. B.E. 2001. EPA /540/S-01/500). Our research group is involved in studies regarding the use of plants for soil phytoremediation (Galante et al., 2005. Proc. SIGA Congress, L04) and, more recently, of unicellular green algae species (green microalgae) for wastewater treatments. Some microalgae species have been recently tested to degrade an array of pollutants such as phenols, polyphenolic aromatic compounds (PAH) and even hormones (Pollio et.al., 1994. Phytochemistry, 37:1269- 1272;. Pinto et.al., 2003. Biotechnol Lett., 25:1657-1659). It is worthy to note that about 2,500 species belong from Chlorophyceae, seldom living in contrasting habitat under severe environmental conditions. So far, a little has been done to exploit this genetic biodiversity bonanza; thus, few reports have been published on enzymes implicated in their degradative action (Semple et.al., 1996. Appl. Envr. Micr, 62:1265-1273). Since a wide collection of green microalgae species are available at the University of Naples, Department of Biological Science, recently we have started a research aimed to (a) find algae species with extracellular phenoloxidase enzymatic activity; (b) identify extracellular enzymes able to degrade xenobiotic like synthetic dyes and other PAHs; (c) clone and overexpress genes producing phenoloxidases in homologous and in heterologous systems, in order to use these enzymes primarily for phytoremediation of milling oil wastewaters. Among phenoloxidaes, we focused our interest on laccases (EC 1.10.3.2) that are phenol-oxidoreductases able to catalyze the oxidation of various aromatic compounds (particularly phenols) with the concomitant reduction of oxygen to water. Selected algae strains were grown in liquid culture at 22°C under continuous light conditions, starting with an inoculum of 0.1 OD. After ten days, the algal growth was measured as optical density at 600 nm. A screening was performed by detecting the laccase activity in the broth medium culture, deprived of algae cells, in the presence of 2,2-azino-bis 3-ethybenz-thiazoline-6-sulfonic acid (ABTS) at 420 nm. The laccase activity was referred to the polyphenol oxidase activity of Trametes versicolor; thus, each positive strain was assayed on industrial azo-dye Remazol Brilliant Blue R (RBBR) and on the natural phenol compound syringaldazine by kinetic analysis. Preliminary results, obtained comparing different species, showed a wide variation both within the same substrate and among the different microalgae. Microalgae strains able to produce and secrete laccase enzymes were further chosen for more detailed genetic studies. To clone phenoloxidase genes from those species, we have started a bioinformatics approach, on the basis of highly conserved coding sequences of laccases already isolated and sequenced from several higher plants. Primers drawn on the alignment of those sequences have been used to amplify genomic DNA.

Salt crystallization is widely recognized as a cause of deterioration of porous building materials. In particular, the crystallization pressure of salt crystals growing in confined pores is found to be the main cause for damage. The aim of this study is to better understand the degradation of porous rocks induced by salt crystallisation and correlate such processes with the intrinsic characteristics of materials. With this intend, an experimental salt weathering simulation has been carried out on two limestones widely used in the Baroque architecture of eastern Sicily. A systematic approach including petrographic, porosimetric and colorimetric analyses, was used to evaluate the correlation among salt crystallisation, microstructural and chromatic variations of limestone. Results showed a quite different resistance of the two limestones to salt damage, and this was found to be strongly dependent on their pore structure and textural characteristics.