High efficiency fluorinated oligo(Ethylenesuccinamide) coating for stone

The protection of stone cultural assets is related to the transformation of the surface characteristic from hydrophilic to hydrophobic/superhydrophobic through the application of a coating. The suitability of a coating depends not only on its capability to dramatically change the surface wettability, but also on other parameters such as the modification of kinetics of water absorption, the permanence of vapor diffusivity, the resistance of the coating to aging and the low volatile organic compound emissions during its application. In this work, an oligo(ethylensuccinamide) containing low molecular pendant perfluoropolyether segments (SC2-PFPE) and soluble in environmentally friendly solvents was tested as a protective agent for historic stone artifacts. Magnetic resonance imaging and relaxometry were employed to evaluate the effects of the surface wettability change, to follow the water diffusion inside the rock and to study the porous structure evolution after the application of SC2-PFPE. A sun-like irradiation test was used to investigate the photo-stability of the product. The results demonstrate that the highly photo-stable SC2-PFPE minimizes the surface wettability of the stone by modifying the water sorptivity without significantly affecting its porous structure and vapor diffusivity. The improved performance of SC2-PFPE in comparison to other traditional coatings makes it a potential candidate as an advanced coating for stone cultural heritage protection

Fibrous mineral detection in natural soil and risk mitigation (1(st) paper)

The paper describes a fibrous mineral detection methodology, which is based on the use of alternating rotary motion sieving equipment. The equipment was redesigned to meet additional requirements with respect to initial ones. Under this methodology, the fine fraction passing through the sieves was recovered and analysed to determine the sedimentology, mineralogy and morphology of the potentially particulating fraction. Reliance was made on the following analytical techniques: laser granulometry, scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) and polarised and phase contrast light microscopy (PLM, PCLM) for fibrous mineral identification and Walton-Beckett / whole field fibre counting. The samples for the analyses came from known areas with fibrous minerals, e.g. Lauria (Basilicata), and less known areas, e.g. the Natural Reserve of Mt. Rufeno (Latium) and Biancavilla (Sicily). With this methodology, fibres may be directly detected in both farmed and unfarmed soil with fibrous minerals and the process may be repeated in the various stages of farming or during works for creation of fire barriers or lanes, hydrogeological restoration etc. The goal is to identify risks arising from the natural occurrence of asbestos upon atypical activities, such as farming and forestry. With regard to exposure, consideration was given to fibrous minerals not currently classified in the relevant legislation, thus going beyond the search for asbestiform minerals in quarry sites located in ophiolite outcrop areas

Survival of atraumatic restorative treatment (ART) sealants and restorations: a meta-analysis

The purpose of this study is to perform a systematic investigation plus meta-analysis into survival of atraumatic restorative treatment (ART) sealants and restorations using high-viscosity glass ionomers and to compare the results with those from the 2005 ART meta-analysis. Until February 2010, four databases were searched. Two hundred four publications were found, and 66 reported on ART restorations or sealant survival. Based on five exclusion criteria, two independent reviewers selected the 29 publications that accounted for the meta-analysis. Confidence intervals (CI) and or standard errors were calculated and the heterogeneity variance of the survival rates was estimated. Location (school/clinic) was an independent variable. The survival rates of single-surface and multiple-surface ART restorations in primary teeth over the first 2 years were 93% (CI, 91–94%) and 62% (CI, 51–73%), respectively; for single-surface ART restorations in permanent teeth over the first 3 and 5 years it was 85% (CI, 77–91%) and 80% (CI, 76–83%), respectively and for multiple-surface ART restorations in permanent teeth over 1 year it was 86% (CI, 59–98%). The mean annual dentine lesion incidence rate, in pits and fissures previously sealed using ART, over the first 3 years was 1%. No location effect and no differences between the 2005 and 2010 survival rates of ART restorations and sealants were observed. The short-term survival rates of single-surface ART restorations in primary and permanent teeth, and the caries-preventive effect of ART sealants were high. Clinical relevance: ART can safely be used in single-surface cavities in both primary and permanent teeth. ART sealants have a high caries preventive effect

Gli animali sentinella: un surrogato della fauna selvatica per un monitoraggio ambientale in aree protette.

World Asbestos Conference 2009 - Taormina 1-3/10/200