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Libraries and archives house a wide variety of documents made of materials of vegetal and animal origin: unbound papers and books, manuscripts and printed books, photographs (negative and positive), prints, maps, available to the public for reading needs, study and information. These materials are often subject to fluctuations in environmental and micro-environmental parameters. For this reason, it is essential to implement constant monitoring and control of environmental conditions and potential deteriogens in order to slow down deterioration processes. The monitoring of the microbial degradation of paper documents in the Historical Archives of Palermo Astronomical Observatory has revealed microorganisms (bacteria and fungi) that may be considered responsible for damaging the items examined, thus enabling an evaluation of the real risks and the proper methodologies to use to avoid future recolonization., Conservation Science in Cultural Heritage, Vol 15, No 2 (2015): Special Issue for Second Conference on Biology and Archaeobiology – from Knowledge to Preventive Conservation

In the early period, even though professional photographers worked with similar techniques and products, their artistic and commercial aims determined different choices and led them to follow different, often personal, recipes. For this reason, identification of the techniques through date and name of the photographer or through some visual features like colour, tonality and surface of the image layer, often needs further investigation to be proved. Chemical characterization, carried out in a non or micro destructive way, can be crucial to provide useful information about the original composition, degradation process, realization technique, in obtaining an indirect dating of the photograph and/or to choose the most correct conservation treatment. In our case, x-ray fluorescence (XRF) analysis was used to confirm the chemical composition of eleven historical photographs dated between the end of the 19th century and the beginning of the 20th, shot in Palermo (Sicily) by a renowned photographer of the time, and pasted on their original cardboards. The elemental identification, obtained with a non destructive approach, provided important information to distinguish among different photographic techniques in terms of distribution and characterization of chemical elements markers in the photographic surface.

A variety of calcareous and siliceous skeletal components are associated with exceptional, still active deposits of modern iron ooids off Panarea, one of the volcanic islands of the Aeolian Arc (Tyrrhenian Sea, Italy). Both ooids and skeletal components occur as loose sediments influenced by submarine hydrothermal fluid vents. Whereas iron ooids are exclusively made of goethite laminae primarily nucleated on volcaniclastic material, sponge spicules – that represent most of the siliceous skeletal component – develop laminated coatings (concretions) of varying sizes. This partial or total coating consists of regularly banded Fe‒rich layers exhibiting the same textural features and mineralogical composition (goethite) of the ooid cortex developed around inorganic cores. Spicules did not reveal any obvious attaching structure or interfingering with the surrounding coating and did not undergo bioerosion or any other evidence of biological intervention during their development. A hydrothermal origin, compatible with the general setting, is therefore proposed for these armoured sponge spicules. We believe that this unique modern case of iron concretions produced on siliceous spicules can contribute to explain other known fossil cases as well as to understand the taphonomy of this type of biogenic silica that seems rarely to have been preserved in such an extreme habitat.

The subject of this present work is a group of nine historical pictures shot in Palermo by the Sicilian photographer E. Interguglielmi in 1912. They are nine matte-collodion prints mounted on the original cardboard supports and all of them show foxing stains affecting the paper surface. In order to characterise the chemical composition of the supports and investigate foxing spots, non-destructive and micro-destructive analysis were carried out. X-rays fluorescence (XRF) analysis was used to characterise the elemental composition of all the mounting boards, allowing a comparison between the foxing spots and non-affected areas. Laser-Induced Breakdown Spectroscopy was used to investigate the presence of lower atomic number elements, not detectable by XRF, while SEM imaging allowed the investigation of surface appearance and nature of original paper samples from the cardboards.

The SE part of Turkey is characterized by a transtensional regime within the complex collision zone between the Anatolian, Arabian and African plates, which is bounded by two main faults, Dead Sea Fault and its splays on east and the Karasu Fault on west. In this tectonic and geodynamic context developed the Amik and further North, Erzin and Toprakkale districts, which are located onshore the Iskenderun Gulf, with the occurrence of a widespread and young alkaline volcanism dated from 1.57 to 0.05 Ma in Amik, and 2.25 to 0.61 Ma in Toprakkale. Here we present the results of a petrochemical and noble gases (He Ar) study performed in basalts and basanites from the Basins in order to constrain the features of the mantle source. The major and trace elements composition indicate that the involved mafic melts could be the result of 0.8–2% partial melting of a predominantly spinel and garnet + spinel mantle, which has typical features of intra-plate OIB magmatism. The 4 He/ 40 Ar* ratios display two distinct ranges, roughly 1, for basalts and basanites respectively. The 3 He/ 4 He ratio of fluid inclusions in olivine crystals ranges from 7.29 to 8.03 Ra (being Ra the atmospheric 3 He/ 4 He ratio of 1.39 × 10 − 6 ), which implies a rather homogenous helium isotope signature of the mantle source. Such values are commonly recorded in MORB-like reservoirs (namely 8 ± 1 Ra), confirming that lavas erupted in SE Turkey did not suffer any important process of crustal contamination. Combining the main evidences from the geochemical data of both rocks and noble gases of fluids inclusions, we suggest that the melt generation of the alkaline magmas was triggered by a stretching lithosphere resulting from asthenosphere upwelling and decompression melting, analogous to geodynamic models of the coeval Syrian alkaline volcanic rocks and the older NW Anatolian rocks, rather than by subduction or plume-related processes. Finally, the combined results of noble gas-rock geochemistry point to a widespread mantle metasomatism as well as absence of crustal assimilation and negligible crustal contamination in contrast to former conclusions based only on the solid rock geochemistry.

The employ of a hyaluronic acid (HA) derivative, bearing octadecyl (C18) and ethylenediamine (EDA) groups, for microfluidic fabrication of nanogels and microfibers is reported in this study. Two HA-EDA-C18 derivatives (125 and 320 kDa) having ionic strength sensitive properties are synthesized and characterized. The control of the rheological properties of HA-EDA-C18 aqueous dispersions by formation of inclusion complexes with hydroxypropyl-β-cyclodextrins (HPCD) is described. Reversibility of C18/HPCD complexation and physical crosslinking is detected in media with different ionic strength through oscillation frequency tests. HA-EDA-C18 125 kDa is employed for nanogel fabrication. Control over nanogel dimension by flow ratio regulation is demonstrated. HA-EDA-C18 320 kDa with HPCD is employed for fabrication of both microfibers and microchannels. Dimension of fibers is controlled by modulating flow ratios. Suitability for biological functionalization is assayed introducing cell adhesive peptides. Adhesion and encapsulation of human umbilical vein endothelial cells is evaluated.