Search results for "heritage"
showing 10 items of 1224 documents
Biodeterioration
2022
The biodeterioration of organic and inorganic materials, as well as polymers, is a complex of alteration processes induced by the growing and metabolic activity of organisms. It can be recognized on monuments, wall paintings, stone, wood, paper, vegetal/animal fibers, and parchment artworks. As defined by Hueck, 1968, biodeterioration is “any undesirable change in the properties of a material caused by the vital activities of organisms”; this definition is accepted as the meaning of the phenomenon. Both macroorganisms (such as animals, plants, and mosses) and microorganisms (such as autotrophic or heterotrophic bacteria, microfungi, cyanobacteria, algae, and lichens) represent the triggers …
Plant products as biocides for conservation of cultural asset sustainable for human and environmental health
2022
In the last decades plants products are increasingly used also in defining innovative procedures for sustainable conservation of cultural heritage. Particularly, essential oils or hydro-alcoholic extracts have been fruitful applied to contrast microbial colonization on organic and inorganic artworks or insect infestation (Anobidae) having regard to the repellent action.
 In this paper, extracts from Asteraceae and Lamiaceae plant families are utilized to counteract widespread microbial colonization (bacteria, cyanobacteria, fungi) due to their antimicrobial activity. In order to define the adequate concentration correlating it to microbial species detected, the antimicrobial activity o…
FRESHWATER CYANOBACTERIA, IDENTIFIED BY MICROSCOPIC AND MOLECULAR INVESTIGATIONS ON A COLONIZED FOUNTAIN SURFACE: A CASE STUDY IN PALERMO (SICILY, IT…
2021
Cyanobacteria or blue algae are ubiquitously present in both fresh and brackish water environments. They also grow in conditions of high humidity, colonizing stones or monuments and fountain surfaces, and creating thick biofilms able to induce biodeterioration in the constituent materials of artefacts. As well as several photoautotrophic organisms, cyanobacteria belong to the microorganisms identified as primary colonizers, playing an important role in stone artwork deterioration. In this study, an analysis was made of the biofilm collected from the stone fountain of the Two Dragons in Palermo (Italy), revealing the presence of cyanobacterial colonies by optical microscopy, due to their pec…
Cnidarian inflammatory reaction and bioactive molecules: from multifunctional role to cultural heritage applications
2015
The renewed interest in the study of genes of immunity in Cnidaria has led to additional information to the scenario of the first stages of immunity evolution revealing the cellular processes involved in symbiosis, in the regulation of homeostasis and in the fight against infections. We investigated the inflammatory response in Anemonia sulcata (Cnidaria: Anthozoa), following injection of various substances different in type and dimension, and observed clear, strong and specific reactions especially after injection of bacteria. The enzymes evaluation (protease, phosphatase and esterase), showing how the injection of different bacterial strains alters the expression of these enzymes suggesti…
Pickering Emulsions Stabilized by Halloysite Nanotubes: From General Aspects to Technological Applications
2022
Besides surfactants, which decrease the interfacial tension between two immiscible liquids, also interfacially active particles can successfully stabilize an emulsion system by attaching at the liquid–liquid interface. The preparation of the resulting Pickering emulsions has been so far investigated starting from the study of the interactions arising between the dispersed droplets and the stabilizers, till the application of these systems in a wide range of different fields. This work is intended to provide an overall overview about the development of Pickering emulsions by considering the most general aspects and scanning the diverse types of solid stabilizers. Among them, Halloysite nanot…
Gli specchi argentati della Collezione Storica degli Strumenti di Fisica dell’Università di Palermo
2021
Nell'articolo presenteremo tre strumenti scientifici di particolare interesse storico-didattico appartenenti alla Collezione Storica degli Strumenti di Fisica dell'Università di Palermo: uno specchio convesso risalente molto probabilmente all'inizio del XIX secolo e una coppia di specchi ustori risalenti molto probabilmente alla metà del XIX secolo. Dopo un'introduzione sullo sviluppo storico degli specchi e il loro principio di funzionamento, descriveremo le caratteristiche fisiche degli strumenti della collezione e gli interventi effettuati. In the paper we will describe three instruments of particular historical and didactic interest belonging to the Historical Collection of Physics Inst…
Diagnostic Multidisciplinary Investigations for Cultural Heritage at Etna Volcano: A Case Study from the 1669 Eruption in the Mother Church at the Ol…
2022
Misterbianco is located on the southern flank of Mt. Etna (Unesco site), in eastern Sicily (Italy). This site, also known as Monasterium Album, has a long and tormented history linked with volcanic activity of Mt. Etna and regional seismicity. This site received much attention in the 2000s when excavation works brought to light a 14th century church remains below the thick layer of the 1669 lava. This study documents the first diagnostic multidisciplinary survey performed at this site 350 years after the eruption: the investigations were performed by using techniques such as ground-penetrating radar, infrared thermography, a terrestrial laser scanner and a drone survey to analyze the site’s…
Virtual three-dimensional model of the subsoil of the church of St. Maria Maddalena d'Alga in Palermo, using high-resolution GPR surveys
2022
The church of Santa Maria Maddalena d'Alga is located in the historic center of Palermo and belongs to the monumental complex of the military district of San Giacomo, in the ancient western fortified area of the city. Today the area hosts a vast military complex, seat of the Command of the Carabinieri Legion of Sicily. The church is elevated with respect to the current floor. During some maintenance works of the church, for the installation of air conditioners, some georadar surveys were carried out to verify the presence of crypts or tombs under the pavement. The investigations made it possible to reconstruct a 3D georadar model and to identify some anomalies under the pavement. Some of th…
Uno strumento di pianificazione per la salvaguardia degli edifici storico-monumentali. Un caso di studio: la chiesa del SS. Salvatore a Naro
2020
Il patrimonio storico, e in particolare gli edifici monumentali, sono i manufatti tra i più vulnerabili nei confronti degli eventi sismici, e spesso determinano anche gravi ripercussioni su quello che comunemente è definito ”rischio urbano”. Per la conservazione e la tutela del patrimonio culturale nei riguardi dell’azione sismica è necessario disporre di strumenti di analisi in grado di permettere la valutazione della vulnerabilità e del rischio, nonché la progettazione degli interventi di miglioramento sismico. Le Linee Guida per la valutazione e riduzione del rischio sismico del patrimonio culturale – allineamento alle nuove Norme tecniche per le costruzioni, G.U. 26.02.2011, n°47 (di se…
Effect of the different data survey scale on assessment of seismic exposure and vulnerability of the historic center of Caltabellotta
2019
The results of the prediction of exposure and seismic vulnerability for the buildings of the historic center of Caltabellotta, obtained with databases of different levels of accuracy, are compared. In particular, the results obtained on the basis of the estimation of the characteristics and of the distribution of the typologies derived from the filling in of the CARTIS sheets on a sector scale are compared with those obtained through a survey from the outside to a building scale. In this latter area, indicators contained in the CARTIS are suitably supplemented with those available in the literature, partly modified to adapt them to the local reality. The vulnerability is evaluated on the ba…