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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123675, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38035409

RESUMEN

Within vibrational spectroscopy techniques, Raman is much more employed than infrared spectroscopy for the study of glassy materials belonging to cultural heritage. This could be due to both a less straightforward interpretation of the spectra and a more difficult application of the technique with portable instrumentations. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) can be exploited in archaeometric investigations because portable and non-invasive. On the other hand, no systematic applications of this technique to historical glasses are found in the literature. This exploratory work reports the DRIFTS investigation of the Corning Archaeological Reference Glasses, widely used as references in the cultural heritage field, and of real case glass samples, with the aim of exploring the potential of this technique to gain information about their composition and alteration. The results, exploiting the association of portable X-ray Fluorescence (pXRF), and, where possible, of EDS microanalyses, are encouraging, setting the samples within a compositional range and highlighting spectral differences for the altered surfaces.

2.
Sci Rep ; 13(1): 13739, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612357

RESUMEN

The implementation of analytical techniques able to certify food quality and origin in a fast and non-destructive way is becoming a widespread need in the agri-food sector. Among the physical non-destructive techniques, X-ray fluorescence (XRF) spectrometry is often used to analyze the elemental composition of biological samples. In this study, X-ray fluorescence (XRF) elemental profiles were measured on tomato samples belonging to different geographical areas in Sicily (Italy). The purpose of this investigation was aiming to establish a protocol for in-situ measurement and analysis able to provide quality assessment and traceability of PGI agri-food products, specifically sustaining health safety and self qualifying bio-chemical signature. In detail, sampling was performed in one of the most tomato productive area of south-eastern Sicily (Pachino district), characterised by a relative higher amount of Organic Carbon and Cation Exchange Capacity, and compared with samples from other growing areas of Sicily, falling in Ragusa province and Mt. Etna region. Experimental data were analyzed in the framework of multivariate analysis by using principal component analysis and further validated by discriminant analysis. The results show the presence of specific elemental signatures associated to several characterizing elements. This methodology establishes the possibility to disentangle a clear fingerprint pattern associated to the geographical origin of an agri-food product.


Asunto(s)
Solanum lycopersicum , Radiografía , Sicilia , Rayos X
3.
J Synchrotron Radiat ; 19(Pt 5): 782-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22898958

RESUMEN

The present work reports a detailed investigation on the speciation of iron in the pigments of decorated pottery fragments of cultural heritage relevance. The fragments come from the Gioiosa Guardia archaeological site in the area of the `Strait of Messina' (Sicily, Southern Italy), and date back to VI-V century BC. The purpose of this study is to characterize the main pigmenting agents responsible for the dark-red coloration of the specimens using non-destructive analytical techniques such as synchrotron radiation X-ray absorption spectroscopy (SR-XAS), a well established technique for cultural heritage and environmental subjects. Absorption spectra were collected at the Fe K-edge on the Italian beamline for absorption and diffraction (BM8-GILDA) at the European Synchrotron Radiation Facility in Grenoble (France). In order to determine the speciation of Fe in the samples, principal component analysis and least-squares fitting procedures were applied to the near-edge part of the absorption spectra (XANES). Details on the local structure around the Fe sites were obtained by analyzing the extended part of the spectra (EXAFS). Furthermore, an accurate determination of the average Fe oxidation state was carried out through analysis of the pre-edge peaks of the absorption spectra. Samples resulted composed of an admixture of Fe(2)O(3) (hematite or maghemite) and magnetite (Fe(3)O(4)), occurring in different relative abundance in the dark- and light-colored areas of the specimens. The results obtained are complementary to information previously obtained by means of instrumental neutron activation analysis, Fourier transform infrared absorbance and time-of-flight neutron diffraction.

4.
Talanta ; 250: 123721, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35841660

RESUMEN

Geopolymers, synthesized starting from aluminosilicate precursors activated with alkaline solutions, constitute a class of materials of high interest as potential substitutes of traditional, cementitious, binders. Infrared spectroscopy is one of the routine analytical techniques employed to study these materials and to verify the occurrence of geopolymerization; on the other hand, its portable version working in diffuse reflection is not enough exploited for their characterization. The aim of this work is therefore to assess the potentiality of Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) in the study of geopolymers. The combination of this technique with Principal Components Analysis (PCA) statistical treatment was used to search for criteria able to discriminate the successful products from those which require a correction in their formulation. Mainly, two groups of geopolymers were studied, based respectively on clay sediments and ceramic waste precursors, in the latter case with the possible addition of metakaolin. These samples were studied both after maturation, comprising several variables in their mix-design and curing, and during the first hours of solidification of the slurry. The results allowed to identify the best formulations within the analyzed groups. Besides, the extension of this study to a wider selection of geopolymers, such as the pumice-, volcanic paleo-soil- and/or metakaolin-based ones, already studied with other techniques, further confirmed the efficacy of DRIFT spectroscopy in the identification of the geopolymerization reaction.


Asunto(s)
Suelo , Arcilla , Análisis de Fourier , Análisis de Componente Principal , Espectroscopía Infrarroja por Transformada de Fourier/métodos
5.
Anal Bioanal Chem ; 399(9): 3147-53, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21311873

RESUMEN

We report on a non-destructive study of Sicilian ceramic fragments of cultural heritage interest, classified as "proto-majolica" pottery and dating back to the twelfth to thirteen centuries AD. The analytical approach used is based on the employment of two totally non-invasive spectroscopic techniques: X-ray fluorescence (XRF), using a portable energy-dispersive XRF analyser, and X-ray absorption spectroscopy, using synchrotron radiation as a probe (SR-XAS). XRF measurements allowed us to collect elemental and spatially resolved information on major and minor constituents of the decorated coating of archaeological pottery fragments, so providing preliminary results on the main components characterizing the surface. In particular, we assigned to Fe and Mn the role of key elements of the colouring agent. With the aim of obtaining more detailed information, we performed SR-XAS measurements at the Fe and Mn K-edges at the Italian BM08 beamline at the European Synchrotron Radiation Facility (Grenoble, France). The experimental data were analysed by applying principal component analysis and least-squares fitting to the near-edge part of the spectra (X-ray absorption near-edge structure) to determine the samples' speciation. From the overall results, umber, a class of brownish pigments characterized by a mixture of hydrated iron and manganese oxides, has been ascribed as a pigmenting agent.

6.
Sci Total Environ ; 761: 143248, 2021 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-33183826

RESUMEN

This work is a part of a research project conducted in order to characterize the volcanic ash from Mount Etna, focusing in particular on the surface reactivity of ashes and possible consequence for human health. In this framework, a sampling campaign began on 16 March 2013, taking advantage of the intense volcanic activity on Etna. The interaction between volcanic ash and human organism was simulated treating two classes of representative Etnean particles with ultrapure water (grainsize of 850 um) and Gamble's solution mimic lug fluids (grainsize <38 µm) with the aim to evaluate the risk due to gastric and respiratory exposure to volcanic particles. The leachates were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Ionic Chromatography (CI) in order to highlight possible dangerous elements released in water solutions according to USGS protocol. Analyses of Gamble's solution highlighted a release of elements smaller than in watery solutions and always below the thresholds established by the Italian law. On the contrary, analyses of watery solutions evidenced, for some elements (B, Cd, Ni and As), levels higher than permitted by Italian law. Considering the effects of these elements on human health, further investigations are necessary and currently carried out in order to better constrain the release process and the specific effects on human organism.


Asunto(s)
Erupciones Volcánicas , Agua , Humanos , Italia
7.
J Hazard Mater ; 400: 123213, 2020 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-32593939

RESUMEN

Volcanic ashes particles are subjected to substantial modification during explosive eruptions. The mineralogical and compositional changes have important consequences on the environment and human health. Nevertheless, the relationship between the speciation of iron (Fe) and the mineralogical composition and particle granulometry of the ashes, along with their interaction with water, are largely unknown. In particular, the Fe oxidation state and the possible formation of new Fe-bearing phases in presence of S, Cl, and F in the plume are key points to assess the impact of the ashes. Fragmental material ejected during volcanic activity (tephra) in 2013, was collected on the Mt. Etna (Italy) and investigated using a multi-technique approach that included conventional Electron Paramagnetic Resonance (EPR), high field EPR (HFEPR), EchoEPR, and Fe K-edge X-ray Absorption Spectroscopy (XAS). These element-selective techniques allowed obtaining a detailed information on the oxidation state and coordination environment of Fe, and of its speciation in the ash samples as a function of the granulometry. A complex mineralogical assemblage, consisting of variable amounts of nanometric crystalline Fe inclusions in a glass matrix, and of Fe-oxides and Fe-sulfur phases was revealed. A risk assessment of the ashes is attempted.

8.
Nanomaterials (Basel) ; 9(4)2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010167

RESUMEN

A nano-silica consolidant and nano-titania modified tetraethyl-orthosilicate were applied on two building stones, a carbonate and a silicate, by brush, poultice or capillary absorption. Neutron radiography was used to monitor capillary water absorption, and to analyse changes in physical properties caused by heat treatment of specimens for the purposes of artificially ageing and different treatment applications with stone consolidants. Moreover, ultrasonic pulse velocity and gravimetrically determined water absorption were analysed to cross-validate neutron radiography. The results reveal that reactive systems like tetraethyl-orthosilicates need an unknown period for polymerisation, which makes nano-silica consolidants more favourable for construction follow-up work. While polymerisation is incomplete, hydrophobic behaviour, water trapping and pore clogging are evident. Within the tetraethyl-orthosilicate treatment, poultice and brushing are strongly influenced by the applicant, which results in wide ranging amounts of water absorbed and anomalous water distributions and kinetics. The carbonate lithotype displays polymerisation initiated in the core of the specimen, while the lateral surfaces are still mostly hydrophobic. Reaction time differences can be attributed to the different amounts of consolidants applied, which is a result of the chosen application settings. Artificial ageing of stone specimens is a prerequisite when mechanical strength gain is studied, as demonstrated by sound speed propagation.

9.
Front Genet ; 9: 514, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30425730

RESUMEN

Emerging evidence suggests that air pollution increases the risk of cardiovascular disease (CVD) and metabolic disorders, adding to the global burden of disease attributable to lifestyle and behavioral factors. Although long interspersed nucleotide elements 1 (LINE-1) methylation has been associated with these disorders, no studies have simultaneously examined the effects of diet and air pollution exposure on DNA methylation. Herein, we evaluated the association of particulate matter (PM with aerodynamic diameters of less than 10 mm) exposure and adherence to Mediterranean Diet (MD) with LINE-1 methylation. Healthy women (n = 299), aged 15 to 80 years, were enrolled in a cross-sectional study. Dietary data and adherence to MD were assessed by a Food Frequency Questionnaire (FFQ) and Mediterranean Diet Score (MDS). PM10 levels during 1-month before recruitment were recorded by monitoring stations and assigned to each woman based on their residential address and day of recruitment. LINE-1 methylation in blood samples was assessed by pyrosequencing and reported as percentage of 5-methylcytosine (5mC). The Mann-Whitney U test, Spearman's rank correlation test and linear regression models were applied. Our results demonstrated, for the first time, an inverse association between adherence to MD and exposure to PM10 with LINE-1 methylation: while higher monthly PM10 exposure decreases LINE-1 methylation level (ß = -0.121; p = 0.037), the adherence to MD increases it (ß = 0.691; p < 0.001). MDS seemed to interact with PM10 levels (p = 0.002) on LINE-1 methylation, as such we confirmed that the effect of MD decreased with increasing PM10 levels (ß = 0.657; p < 0.001 in the first tertile; ß = 0.573; p < 0.001 in the second tertile; ß = 0.551; p < 0.001 in the third tertile). Thus, we suggest that LINE-1 methylation is a possible mechanism underpinning environment-related health effects, and encourage further research to evaluate whether the adherence to the MD could counteract the negative effect of PM10 exposure.

12.
BMJ Open ; 7(4): e014756, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28377395

RESUMEN

INTRODUCTION: Environmentally-related health and disease are the result of the exposome, the totality of a person's environmental exposures, from all sources and routes, across their lifespan. Epigenetic phenomena, including DNA methylation, can be potentially modified by environmental and lifestyle factors, and result in environmental reprogramming of the genome for exposed individuals and for future generations of offspring. OBJECTIVE: The objective of the project is to evaluate the risk of DNA hypomethylation due to air pollution, Mediterranean diet adherence, folate intake, and demographic and socioeconomic factors, in healthy women living in the metropolitan area of Catania, Italy. METHODS AND ANALYSIS: Non-pregnant healthy women will be enrolled in a cross-sectional study. Sociodemographic, lifestyle and dietary intake information will be collected. LINE-1 methylation will be measured by pyrosequencing. The participants' home addresses will be geocoded and each woman will be assigned to the closest monitoring station for particulate matter (PM) exposure assessment. Mineralogical-chemical characterisation of PM and cellular model assays will be performed. An integrated approach will be designed to estimate the combined possible effect of air pollution, Mediterranean diet adherence, folate intake and other lifestyle characteristics on LINE-1 methylation levels. ETHICS AND DISSEMINATION: The project has been approved by the ethics committees of the involved institution and funded by the University of Catania (Finanziamento della Ricerca, FIR 2014). All participants will be fully informed of the purpose and procedures of the study, and signed written consents will be obtained. All the data collected will be treated confidentially and analysed in an aggregate and anonymous way. The results will be published in peer-reviewed journals and communicated to local public health agencies, in order to provide essential information for timely and effective public health action.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Enfermedades Ambientales/epidemiología , Monitoreo del Ambiente/métodos , Epidemiología Molecular/métodos , Material Particulado/análisis , Salud Pública , Adolescente , Adulto , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Estudios Transversales , Exposición a Riesgos Ambientales/efectos adversos , Salud Ambiental , Femenino , Voluntarios Sanos , Humanos , Incidencia , Italia/epidemiología , Persona de Mediana Edad , Factores Socioeconómicos , Adulto Joven
13.
Appl Spectrosc ; 70(8): 1346-55, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27340217

RESUMEN

(13)C cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) and µ-Raman spectroscopy were applied to characterize Sicilian amber samples. The main goal of this work was to supply a complete study of simetite, highlighting discriminating criteria useful to distinguish Sicilian amber from fossil resins from other regions and laying the foundations for building a spectroscopic database of Sicilian amber. With this aim, a private collection of unrefined simetite samples and fossil resins from the Baltic region and Dominican Republic was analyzed. Overall, the obtained spectra permitted simetite to be distinguished from the other resins. In addition, principal component analysis (PCA) was applied to the spectroscopic data, allowing the clustering of simetite samples with respect to the Baltic and Dominican samples and to group the simetite samples in two sets, depending on their maturity. Finally, the analysis of loadings allowed for a better understanding of the spectral features that mainly influenced the discriminating characteristics of the investigated ambers.

14.
Appl Spectrosc ; 70(9): 1420-31, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27520839

RESUMEN

This work is a part of a large scientific project aimed at highlighting the potential of portable Raman equipment in characterizing jewelry materials preserved in museums, carried out in collaboration with gemologists and archeologists. In detail, we report the results of a measurement campaign performed for the study of gems and jewels preserved in the well-known Medagliere section at the Paolo Orsi Regional Museum of Siracusa (Sicily). The studied materials consist of exquisite examples of engraved loose gems and really rare examples of Hellenistic-Roman jewels, mainly coming from relevant Sicilian archaeological sites. Portable Raman measurements have been carried out using two instruments equipped with different excitation wavelengths. The obtained results have allowed for a complete characterization of the studied gemological materials, also suggesting sometimes misclassification for some valuable objects and gems.

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