Integrated analytical methodologies for the study of corrosion processes in archaeological bronzes

Abstract The investigations on structure and micro-chemical composition of archaeological metal alloys are needed in archaeometry. The aim of this study is devoted both to acquire information about their provenance and production technology, and to improve our understanding about the corrosion processes. In this paper we present the study of the corrosion phenomena of bronze samples, laboratory-made according to binary, ternary and quaternary alloys typical of Roman archaeometallurgical production through an integrated methodology based on the use of non or micro invasive physical techniques. Among the analysed samples, two were artificially aged through burial in the archaeological site of…

Preliminary magnetic resonance relaxometric analysis of Fricke gel dosimeters produced with polyvinyl alcohol and glutaraldehyde

This work describes the preliminary analysis of Fricke gels dosimeters characterized by a new formulation making use of a matrix of polyvinyl alcohol cross-linked by adding glutaraldehyde and analyzed by means of nuclear magnetic resonance relaxometry. In previous optical studies, these gels have shown promising dosimetric features in terms of photon sensitivity and low diffusion of ferric ions produced after irradiation. In this work, we used a portable nuclear magnetic resonance relaxometer to measure the relaxation times (which are important for dosimetric applications) of these gel materials. For this purpose, we performed a study for optimizing the acquisition parameters with a nuclear…

XRF and LIBS integrated analysis to identify the chemical composition and the conservation state of photographic and paper materials

Degradation of stone materials in the archaeological context of the Greek-Roman Theatre in Taormina (Sicily, Italy)

In the present work results on the degradation phenomena of stone materials in the Ancient Theatre of Taormina, one of the most important Greek–Roman monuments of Sicily, are reported. Artificial stone materials in different conservation conditions were investigated. Samples of salt efflorescences from brick walls and degraded setting mortars were taken from the open gallery in “summa cavea”. The chemical, physical and structural characterization was performed by means of X-Ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF), both in situ and ex situ. Results showed that the deterioration of stone materials is due to the aggressive action of the enviro…

Applicabilità del metodo GALDIT per la valutazione della vulnerabilità di acquiferi costieri siciliani

Application of Electron Spin Resonance technique in neutron dosimetry

Along with the Neutron Capture Therapy (NCT) development and with the use of thermal neutrons for radiotherapeutic purposes, many efforts have been devoted to the beam characterization in order to optimize the therapy procedures. Reliable dosimetric measurements should be able to determine the various components (neutronic and photonic) of the mixed beam usually employed for therapy [1]. We have studied the effect of the additive such as gadolinium and 10B-boric acid on the neutron sensitivity of alanine ESR dosimeters exposed to a gamma and mixed (n, gamma) field mainly composed by thermal neutrons. We have chosen both this additive nuclei because of their very high capture cross section t…

Diffusion and sensitivity characteristics of a chemically cross-linked PVA-Fricke gel dosimeter

Introduction: Current radiotherapy techniques implement treatment plans based on volumetric distributions of dose with complex shapes and sharp gradients. The agreement between these plans and the dose that is truly delivered is very challenging to verify. Thus, there is the need for a dosimetric system that is truly three dimensional, sensitive to radiation in each point and tissue equivalent. In this framework, great interest is encountered by radio-chromic gel dosimeters. In order to address the limitations of gels based on natural matrices, some investigators have proposed dosimeters based on poly vinyl alcohol (PVA) made by freezing-thawing cycles. Even though these gels have a low dif…

Characterization of the ESR response of alanine dosimeters to low-energy (1-40 keV) X-rays

The aminoacid L-a-alanine has attracted considerable interest for use in radiation ESR dosimetry and has been formally accepted as a secondary standard for high-dose (kGy) and transfer dosimetry . The accuracy of the method is quite high, largely due to the low dependence of the alanine response on various irradiation parameters (photon energies above 100 keV, dose rate, temperature, etc.). Furthermore, this system presents alinear response to dose, fairly high sensitivity, tissue equivalence, absence of fading, small dimensions, ruggedn ess, and non-destructive readout. In this work, we examined the energy dependence of alanine ESR dosimeters in the low energy X-photon energy range between…

Environmental Metal Pollution Considered as Noise: Effects on the Spatial Distribution of Benthic Foraminifera in two Coastal Marine Areas of Sicily (Southern Italy)

We analyze the spatial distributions of two groups of benthic foraminifera (Adelosina spp. + Quinqueloculina spp. and Elphidium spp.), along Sicilian coast, and their correlation with six different heavy metals, responsible for the pollution. Samples were collected inside the Gulf of Palermo, which has a high level of pollution due to heavy metals, and along the coast of Lampedusa island (Sicily Channel, Southern Mediterranean), which is characterized by unpolluted sea waters. Because of the environmental pollution we find: (i) an anticorrelated spatial behaviour between the two groups of benthic foraminifera analyzed; (ii) an anticorrelated (correlated) spatial behaviour between the first …

Investigation of alanine with gadolinium for ESR dosimetry at TRIGA Mark II reactor of Mainz

In this work we have studied the response of alanine pellets with and without gadolinium exposed to the thermal column of the TRIGA Mark II research reactor at the University of Mainz

NDT for the detection and characterization of superficial treatments on stone material from archaeological sites of Merida (Spain)

Spettrofotometria per il monitoraggio degli interventi di restauro: valutazione tramite PCA

La realizzazione di indagini spettrofotometriche per il monitoraggio delle variazioni cromatiche pone la necessità di gestire un elevato numero di dati richiedendo l’utilizzo di analisi statistiche. A tale scopo, la PCA è stata applicata a dati spettrofotometrici relativi a diverse tipologie di superfici (musive, marmoree, etc). Tale metodologia permette di valutare in maniera efficace gli effetti generati a seguito del restau;ro, evidenziando la correlazione tra tutte variabili spettrofotometriche. La distribuzione in cluster dei dati consente di visualizzare la variabile che maggiormente contribuisce allo spostamento cromatico, permettendo il monitoraggio differenziato del comportamento d…

La spettroscopia ad ablazione laser per analisi stratigrafiche: esempi di applicazioni per lo studio dei beni culturali

La spettroscopia ad ablazione laser (LIBS), a differenza di altre tecniche d'indagine, permette di condurre analisi stratigrafiche anche direttamente sul campione tramite impulsi consecutivi sullo stesso punto. Le attività condotte hanno riguardato l'ottimizzazione dei parametri strumentali (laser energy, delay, exposition time) per verificare la possibilità di ottenere profili di profondità degli elementi chimici costituenti materiali di differente tipologia (bronzi archeologici, lapidei, materiali pittorici, etc.), valutando anche l'influenza delle variabili presenti (spessori, composizione, proprietà del plasma). Tale approccio metodologico, seppur micro-distruttivo, evita la necessità d…

Investigation of relaxation times of irradiated Fricke gels by means of nuclear magnetic resonance relaxometry

Fricke gel dosimeters are ideal candidates to provide 3D maps of dose distributions and are particularly useful in the plann ing and verification phase of radiotherapy treatments. One of the most effective experimental techniques to reconstruct dose maps is magnetic resonance imaging (MRI). This measures th e nuclear relaxation times variations induced by irradiation. In this work, we analyzed Fricke gels with and without Xylenol Orange by means of a single side-NMR relaxometer (which is abl e to provide information on both relaxation relaxation times T1 and T2 and is mainly used in the field of diagnostics for Cultural Heritage [1-2] to perform porosimetry meaurements). Our goal was to per…

Qualitative and quantitative characterization of historical pigments by XRF spectrometry

Electron Spin Resonance and Thermoluminescence dating of shells and sediments from Sambaqui (shell mound) Santa Marta II, Brazil

In Tupi, the word Sambaqui means “mound of shells”. These archaeological sites are cultural vestiges left by the prehistoric occupation of the Brazilian coast from five to six thousand years ago. Mollusks, fishes, and other marine edible foods were important for the survival of this population. The remains of foods, mainly shells, were heaped up, giving a mound of different proportions, which became part of the landscape of the Brazilian coastal plain. Due to the large number of Sambaquis in Brazil and considering that Sambaqui Santa Marta II, Laguna, SC, has not yet been dated, Electron Spin Resonance (ESR) measurements were performed in aragonite shells collected from different layers of …

Studio integrato per la caratterizzazione dei laterizi

Nanostructured protective for historical-artistic stone materials: evaluation of effectiveness and persistence by non invasive techniques

Nuovi contributi alla valutazione del rischio d'inquinamento degli acquiferi nella fascia costiera dell regione carsica nebroidea (Sicilia nord-orientale)

Testing and calibration of ESR response of Fricke gel dosimeters in mixed neutron-gamma fields

EPR/ALANINE PELLETS WITH LOW Gd CONTENT FOR NEUTRON DOSIMETRY

This paper reports on results obtained by electron paramagnetic resonance (EPR) measurements and Monte Carlo (MC) simulation on a blend of alanine added with low content of gadolinium oxide (5 % by weight) to improve the sensitivity to thermal neutron without excessively affecting tissue equivalence. The sensitivity is enhanced by this doping procedure of more an order of magnitude. The results are compared with those obtained with the addition of boric acid (50 % by weight) where boron is in its natural isotopic composition in order to produce low-cost EPR dosemeters. The gadolinium addition influences neutron sensitivity more than the boron addition. The presence of additives does not sub…

DOSIMETRIA DI FASCI NEUTRONICI TRAMITE SPETTROSCOPIA DI RISONANZA PARAMAGNETICA ELETTRONICA (EPR)

Non-invasive characterization of archaeological polychrome pottery and metallic artefacts: advantage and limits of XRF in situ analysis

"Historical pigments characterisation by quantitative X-ray fluorescence"

Abstract Most of the historical paints are mainly constituted by inorganic pigments, either pure or mixed, spread on the surfaces using different binding agents. The knowledge of the exact amount of different constituents of the paint, as well as of the mixing and pictorial techniques, is crucial for a careful program of conservation of polychrome works. Moreover, since the availability of these pigments has been changing through the centuries, their identification and chemical characterisation is useful to acquire or deepen information about the artist and his/her work. This information can also be useful for authentication purposes through relative dating because the identification of one…

Temporal trends of heavy metals in sediment core from the gulf of Palermo (Sicily, Italy)

The evaluation of long–term heavy metal concentrations in the Gulf of Palermo was carried out in this study. Measurements of Cr, Cu, Hg, Pb and Zn concentrations were performed by atomic absorption spectrophotometry (AAS) on dated fractions of a sediment core, dated by the 210Pbex method. They are found to cover a time period from 1951 to 2004. The constant sedimentation rate model was used for dating. Specific activities of 137Cs have also been measured in the sediment core sections as a check of the time scale derived by the 210Pbex method. A time-series analysis based on temporal decomposition was used in order to investigate the presence of heavy metal pollution trend. The additive comp…

Foraminiferi bentonici, metalli pesanti e radioattività - ARPAVIEW

Analisi statistica tramite PCA su dati colorimetrici di tessere musive pavimentali

Degradation study of XVIII century graffiti on the walls of Chiaramonte Palace (Palermo, Italy)

A systematic investigation of the original materials and the degradation phenomena induced by soluble salts on the wall matrix and on the graffiti of the Inquisition jails of Chiaramonte Palace in Palermo (Italy) was carried out. Built in the XIV century, Chiaramonte Palace was used as Inquisition court during the XV–XVI centuries. The ancient graffiti, recently discovered, represent a unique historical witness of the prisoners that lived during that terrible period. In order to study the nature, the amount and the distribution of the salts in the masonry, stone materials sampled at different depth from the wall matrix and saline efflorescences were analysed. Different physical techniques w…

Gilding and pigments of Renaissance marble of Abatellis Palace: non-invasive investigation by XRF spectrometry

Most of the artworks constituting the collection of Renaissance statuary of Abatellis Palace in Palermo (Sicily) show evidence of colour layers and fragments of gold foil that probably once covered the whole marble surface. The restoration of some of these statues has allowed to carry out archaeometric studies about the painting technique and to highlight the original materials and inclusion present on the precious marbles by two famous Italian sculptors of the Renaissance, Francesco Laurana and Antonello Gagini. The measurements have been performed in situ through the integrated use of two non-invasive techniques: visible fluorescence stimulated by ultraviolet light and X-ray fluorescence.…

Correlation between ferrous ammonium sulfate concentration, sensitivity and stability of Fricke gel dosimeters exposed to clinical X-ray beams

Abstract This work describes the characterization of various Fricke-Agarose-Xylenol gels (FXG) dosimeters using NMR relaxometry and MRI analysis. Using X-rays from a clinical linear accelerator (LINAC), the gels were irradiated in the dose range from 0 Gy to 20 Gy. The photon sensitivity of the FXGs was measured in terms of NMR relaxation rates; its dependence on radiation dose was determined as a function of ferrous ammonium sulfate contents (from 0.5 mM to 5 mM). Furthermore, the stability of the NMR signal was monitored over several days after irradiation. These measurements were aided by Magnetic Resonance Imaging (MRI) scans which allowed three-dimensional (3D) dose mapping. In order t…

Proprietà del segnale ESR di dosimetri a tartarato di ammonio irradiati con radiazioni di diverso LET

Impiego delle radiazioni ionizzanti per il trattamento degli alimenti a scopo conservativo

Gel di Fricke: studio della risposta NMR in funzione della concentrazione di ferro ed utilizzo dosimetrico in ambito clinico (3D MRI)

Analysis of the response of PVA-GTA Fricke-gel dosimeters with clinical magnetic resonance imaging

Abstract Fricke gel dosimeters produced with a matrix of Poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA) were analyzed with magnetic resonance imaging (MRI). Previous studies based on spectrophotometry showed valuable dosimetric features of these gels in terms of X-ray sensitivity and diffusion of the ferric ions produced after irradiation. In this study, MRI was performed on the gels at 1.5 T with a clinical scanner in order to optimize the acquisition parameters and obtain high contrast between irradiated and non-irradiated samples. The PVA gels were found to offer good linearity in the range of 0–10 Gy and a stable signal for several hours after irradiation. The sensitivi…

Nuclear Magnetic Resonance investigation of PVA-GTA FRicke gel dosimeters exposed to clinical photon beams

Fricke Xylenol Gel (FXG) dosimetric system is based on the radiation induced oxidation of ferrous (Fe2+) to ferric (Fe3+) ions. The application of Fricke gels for ionizing radiation dosimetry is continuously increasing worldwide due to their many favorable properties. However, one of their shortcomings is that ferrous and ferric ions diffuse in the gel matrix. To maintain the spatial integrity of the dose distribution, Fricke gels must be undergoing measurement within a few hours of their irradiation, so that ferric ions remain close to their point of production. Thus, the spatial integrity of the dose distribution in the Fricke gel is maintained. The gel matrix also contributes to the oxid…

LIBS analysis for a stratigraphic study on Cultural Heritage material

Characterization of Fricke gel dosimeters exposed to gamma rays and neutrons

The use of bioindicators (Posidonia oceanica and benthic foraminifera) to evaluate metal pollution in a complex ecological system: marine coastal environment.

PRIN 2007: tecniche innovative per la definizione dello stato di degrado nei metalli

Neutron dosimetry by means of electron spin resonance (ESR) tecnique

Along with the Neutron Capture Therapy (NCT) development and with the use of thermal neutrons for radiotherapeutic purposes, many efforts have been devoted to the beam characterization in order to optimize the therapy procedures. Reliable dosimetric measurements should be able to determine the various components (neutronic and photonic) of the mixed beam usually employed for therapy. We have studied the effect of the additive such as gadolinium and 10B-boric acid on the neutron sensitivity of alanine ESR dosimeters exposed to a gamma and mixed (n, gamma) field mainly composed by thermal neutrons. We have chosen both this additive nuclei because of their very high capture cross section to th…

Sensibilità e stabilità dei dosimetri gel di tipo Fricke esposti ai fotoni nel range clinico in funzione della concentrazione di ferro e degli additivi presenti: 3D MRI per applicazioni dosimetriche

Le statue rinascimentali di palazzo Abatellis: caratterizzazione delle dorature e dei pigmenti tramite spettrometria XRF.

Study of optical absorbance and MR relaxation of irradiated Fricke Xylenol Orange Gel Dosimeters

Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measurements pe…

Characterization of the ESR response of alanine dosimeters to low-energy Cu-target X-tube photons

Abstract This article describes Electron Spin Resonance (ESR) response measurements of Kodak BioMax alanine films exposed to low-energy X-rays from a Cu-target tube operating at 20 kV. Commercial alanine detectors were used to ensure maximum reproducibility of the results, while the choice of a film was due the low penetration of the soft X-rays. X-ray energy spectra and fluences were determined with an innovative digital semiconductor detector system. These data were used to quantify the irradiation of the alanine films in terms of absorbed dose to water. The alanine films were found to present a stable response, highly linear with dose. To our knowledge, these data have not been previousl…

LOW DOSE CHARACTERIZATION OF FRICKE GEL DOSIMETERS BY OPTICAL ABSORBANCE AND MR RELAXATION METHODS

Introduction Fricke gel dosimeters allow measurements of 3D dose distributions and can be an effective tool for dosimetry verifications in radiotherapy. Various authors have reported drawbacks of the gels affecting the accuracy in case of low dose measurements. Purpose This study aims at investigating such drawbacks and at establishing the conditions for an optimal use of the gels. Materials and methods Our dosimeters consist of gels infused with a Fricke ferrous sulphate solution combined with xylenol orange (XO). Two kinds of xylenol orange (XO) and two different gelling agents (gelatin from porcine skin and Agarose) were utilized. Gels are red out by light absorption techniques: images o…

Integrated characterization study of building materials in the greek roman theatre of Taormina

Distribution of Heavy Metals in Marine Sediments of Palermo Gulf (Sicily, Italy)

Concentrations of Cr, Cu, Hg, Pb and Zn have been measured, by atomic absorption spectrophotometry, in the fine fraction (<63 μm) of surface sediments collected in 30 sites in the Palermo Gulf (Sicily, Italy) in order to assess the levels and the spatial distribution of these elements. Enrichment factors calculated with respect to clean areas have been considered to discriminate between levels due to background or to pollution contributions. The sampling stations, which form a grid inside these areas, are characterized by geographic proximity and by the presence of pollution sources. Ratio matching technique along with hierarchical clustering, minimum spanning tree and principal component a…

Study of optical absorbance and MR relaxation of Fricke xylenol orange gel dosimeters

Abstract Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measur…

Non-destructive physical measurements for the study of museum environments and characterization of archaeological artifact

Mercury levels in Engraulis encrasicolus and Sardina pilchardus in the Strait of Sicily

NUCLEAR MAGNETIC RESONANCE RELAXOMETRY AND IMAGING FOR DOSIMETRY WITH AGAROSE FRICKE GEL

Introduction: Fricke Xylenol Gel (FXG) dosimetric system is based on the radiation induced oxidation of ferrous to ferric ions. In this kind of gels it can occur that ferrous and ferric ions diffuse in the gel matrix. To preserve the spatial distribution of the dose from diffusion, Fricke gels must be undergoing measurement within a few hours of their irradiation. Thus, the spatial integrity of the dose distribution in the Fricke gel is maintained. The oxidation of ferrous ions also causes a reduction of the longitudinal nuclear magnetic relaxation time which can be measured by means of nuclear magnetic resonance (NMR) instrumentation. In this work we performed NMR relaxometry and MR imagin…

PVA-GTA Fricke gel: studio della risposta NMR in funzione della concentrazione degli additivi e studi preliminari con scanner MRI 7 T

Sono stati analizzati tramite rilassometria NMR ed acquisizioni MRI dosimetri gel di tipo Fricke realizzati utilizzando un'innovativa matrice gel sintetica e tessuto equivalente: Polyvinyl alcohol (PVA) attivando chimicamente il processo di gelificazione tramite l'aggiunta di Glutaraldehyde (GTA). Questi gel sono stati irradiati con fasci di fotoni (LINAC) nel range 0--20 Gy. Per valutare la sensibilità a fotoni è stata studiata la dipendenza dei tempi di rilassamento nucleari dalla dose e dalla concentrazione di ferro nei gel. Inoltre è stata monitorata la stabilità del segnale dopo l'irraggiamento. Acquisizioni preliminari MRI con uno scanner MRI da 7 T sono state affiancate alle misure N…

Neutron ESR dosimetry through ammonium tartrate with low Gd content.

This paper continues analyses on organic compounds for application in neutron dosimetry performed through electron spin resonance (ESR). Here, the authors present the results obtained by ESR measurements of a blend of ammonium tartrate dosemeters and gadolinium oxide (5 % by weight). The choice of low amount of Gd is due to the need of improving neutron sensitivity while not significantly influencing tissue equivalence. A study of the effect of gadolinium presence on tissue equivalence was carried out. The experiments show that the neutron sensitivity is enhanced by more than an order of magnitude even with this small additive content. Monte Carlo simulations on the increment of energy rele…

Studio della glow curve di TLD irradiati con neutroni termici

DOSimetria in Situazioni di Emergenza Radiologica (DOSSIER)

ASPRACOAST: A model of integrated coastal zone management of the eastern part of the Gulf of Palermo (Sicily, Italy)

Analisi Quantitativa su miscele di pigmenti tramite XRF

Ori e cromie dei marmi rinascimentali di Palazzo Abatellis: indagine non invasiva tramite spettrometria XRF.

Analysis of spatial diffusion of ferric ions in PVA-GTA gel dosimeters through magnetic resonance imaging

Abstract This work focused on the analysis of the temporal diffusion of ferric ions through PVA-GTA gel dosimeters. PVA-GTA gel samples, partly exposed with 6 MV X-rays in order to create an initial steep gradient, were mapped using magnetic resonance imaging on a 7T MRI scanner for small animals. Multiple images of the gels were acquired over several hours after irradiation and were analyzed to quantitatively extract the signal profile. The spatial resolution achieved is 200 μm and this makes this technique particularly suitable for the analysis of steep gradients of ferric ion concentration. The results obtained with PVA-GTA gels were compared with those achieved with agarose gels, which …

Datazione di materiali lapidei

XRF ANALYSES ON MOSAIC TESSERAE OF THE PALATINE CHAPEL OF PALERMO

A geophysical and geochemical approach for seawater intrusion assessment in the Acquedolci coastal aquifer (Northern Sicily)

Vertical electrical sounding (VES’) surveys and chemical analyses of groundwater have been executed in the coastal plain of Acquedolci (Northern Sicily), with the aim to circumscribe seawater intrusion phenomena. This urbanized area is representative of a more general problem interesting most of Mediterranean littoral areas, where intensive overdraft favors a heavy seawater intrusion through the coastline. Aquifer resistivity seems decisively to be conditioned by the chlorine and magnesium content in the main aquifer of the region. Schlumberger VES’, together with piezometric and chemical–physical information of groundwater, allowed us to perform hydrogeological and geophysical elaborations…

Applicability of GALDIT assessing vulnerability model in Sicily coastal aquifers.

GAS CHROMATOGRAPHIC/MASS SPECTROMETRIC AND MICROBIOLOGICAL ANALYSISES ON IRRADIATED CHICKEN

209 New Fricke gel with high sensitivity and low diffusion for 3D-MRI dosimetry

Purpose Fricke gel (FG) dosimeters are good candidates for 3D dose assessment in biological materials. Their effective atomic number and density are similar to those of soft tissue. In view of their chemical and morphological characteristics, FG serve as dosimeters and as phantoms at the same time. FG dosimeters are obtained by incorporating an acidic aqueous solution of ferrous ions Fe2+ into a gel matrix. In order to address the limitations of gels based on natural matrices, we have studied FG produced with a matrix of poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA). Materials and methods The proposed gel contains 10% w/v of PVA and GTA of 1%w/v. A common formulation agaro…

Inquinamento da metalli pesanti in ambiente marino in correlazione con la distribuzione dei foraminiferi bentonici

Nuclear magnetic resonance relaxometry and imaging for dosimetry with agarose Fricke gel

ESR dosimetry with alanine added with Gadolinium in TRIGA reactor of Mainz

Ulteriori valutazioni sull’impiego della Principal Component Analysis su dati colorimetrici di tessere musive pavimentali

Risposta TL di dosimetri irradiati con radiazione di diverso LET

Advances in contamination risk setting of aquifers: the karst Nebrodi region (Sicily)

EPR dating of shells from Malhada Marsh, Rio de Janeiro, Brazil

The formation of the coastal plain of the Brazilian sea is mainly due to the fluctuation of relative sea level in the past. Armacao dos Buzios or simply Buzios is a municipality in the microregion of lakes, in the state of Rio de Janeiro. In this region there is a lowland area about two meters above current sea level. This lowland area is also known as coastal plain of Una River. It is expected that during the Holocene period the sea level reached a maximum about 2.5 meters above the current level. During that time billions of mollusks lived and proliferated in the shallow waters around the coastal plain of the Una River. As they died their shells formed a layer in the soil including Malhad…

Heavy metals in the fine fraction of coastal sediments from Gulf of Palermo.

Characterization of Fricke gel dosimeters exposed to clinical photons beams and of MRI dosimetrical applications

A degradation study of XVIII century graffiti on the walls of Chiaramonte Palace (Palermo, Italy)

Dosimetry of Mainz reactors by means of ESR dosimetry with alanine added with gadolinium

Benthic foraminifera assemblages in coastal marine ecosystem and relationship with metal distribution. A spatial study along Sicilian coasts.

COMPARATIVE ANALYSIS FOR THE ASSESSMENT OF RESTORATION TREATMENTS ON STONE MATERIAL FROM THE ROMAN THEATER OF MERIDA (SPAIN)

A GEOREFERENCE DATABASE AND A GEOGRAPHIC INFORMATION SYSTEM FOR PALERMO PLAIN AND GULF (WESTERN SICILY): AQUIFERS AND MARINE ENVIRONMENTS

Studio di assorbanza ottica e rilassometria RM in dosimetri a gel di Fricke

I dosimetri a gel di Fricke con xylenol-orange, analizzati otticamente, presentano alcune limitazioni se impiegati per misure di basse dosi (pochi Gy o meno), per irraggiamenti di lunga durata o per individuare procedure di calibrazione che permettano l'utilizzo in radioterapia. Le difficoltà derivano da variazioni nello spettro di assorbanza verosimilmente dovute a variazioni dei legami degli ioni ferrici con lo xylenol-orange. Sono state effettuate misure: i) di assorbanza ottica, anche spettrometrica, per dosimetri irraggiati a diverse dosi e a diversi tempi rispetto all'irraggiamento; ii) di rilassometria RM per valutare le variazioni dovute al solo aumento del numero di ioni ferrici.

Influence of waste water in marine ecosystem: preliminary data on benthic foraminifera assemblages and metal concentration in marine sediments

Studio e calibrazione della risposta ottica ed NMR di dosimetri gel di tipo Fricke (FXG) in campi misti neutroni-gamma per applicazioni cliniche

Organismi unicellulari "spie" dell'inquinamento dell'ambiente marino.

Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages

Abstract The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used…

Datazione di materiali ceramici e lapidei

Gas chromatographic/mass spectrometric and microbiological analyses on irradiated chiken

Ionizing radiation is widely used as treatment technique for food preservation. It involves among others reduction of microbial contamination, disinfestations, sprout inhibition and extension of shelf life of food. However, the commercialization of irradiated food requires the availability of reliable methods to identify irradiated foodstuffs. In this paper, we present results on the application to irradiated chicken of this method, based on the detection, in muscle and skin samples, of the peaks of ions 98 Da and 112 Da, in a ratio approximately 4:1, typical of radiation induced 2-dodecylcyclobutanones (2-DCB). Aim of the work was also to study the time stability of the measured parameters…

Nuovi gel di Fricke ad alta sensibilità e bassa diffusione per dosimetria 3D tramite MRI

One of the most recent and promising developments in radiotherapy dosimetry was the introduction of 3D radiationsensitive gels. These gels present tissue equivalent composition and density, so they also serve as phantoms, and their response is largely independent of radiation quality and dose rate. Some gels are infused with ferrous sulfate and rely on the radiation-induced oxidation of ferrous ions to ferric ions (Fricke-gel). In this work Fricke gel dosimeters produced with a matrix of poly-vinyl alcohol (PVA) cross-linked with glutaraldehyde (GTA) were analyzed with magnetic resonance imaging (MRI). This work focused on the analysis of the temporal diffusion of ferric ions through PVA-GT…

ESR response of watch glasses to proton beams

In this paper we have analyzed the electron spin resonance (ESR) signal of watch glasses irradiated with %60 MeV proton beams in the dose range between 1 and 105 Gy. The composition of samples expressed in oxides weight percentages has been obtained carrying out X-ray fluorescence spectrometry (XRF) mea- surements. The ESR signal has been studied in terms of its dependence on microwave power and modulation field in order to choose the optimal recording parameters. The dependence of the radioinduced signal on the exposure dose has been investigated. A numerical procedure aimed at improving the sensitivity in the low dose range has been developed.

APPLICATION OF THE ESR SPECTROMETRY TO EVALUATE THE ORIGINAL DOSE IN IRRADIATED FOOD CONTAINING HYDROXIAPATITE

IDENTIFICAZIONE CON GC/MS E INDAGINE MICROBIOLOGICA DI POLLO IRRADIATO

DOSE RECONSTRUCTION IN IRRADIATED OREGANO BY THERMOLUMINESCENCE DOSIMETRY

Cyclic influences on the heavy metal chronology in a Central Mediterranean area (Palermo Gulf, Italy)

PurposeThe evaluation of long-term heavy metal concentrations in the Gulf of Palermo (Italy) has been carried out in order to investigate how changes of pollution levels in the last 50 years can be reflected in marine sediments. Measurements of Cr, Cu, Hg, Pb, and Zn concentrations were performed on dated fractions of a sediment core. Time series analysis has allowed to obtain information on the chronology of the heavy metal pollution of the area and to identify seasonal components and trends.Materials and methodsHeavy metal concentrations in the <63 μm fraction of core sections were obtained by Atomic Absorption Spectrophotometry, after wet sieving, drying, and digestion procedures. Dating…

Sensibilità e stabilità dei dosimetri gel di tipo Fricke esposti ai fotoni nel range clinico in funzione della concentrazione di ferro: 3D MRI ed applicazioni dosimetriche

Applicazione Integrata di Tecniche Analitiche per la Caratterizzazione di Pigmenti Storici

VALUTAZIONE DELL'EFFICACIA E DURABILITÀ DI PROTETTIVI NANOSTRUTTURATI APPLICATI SU CAMPIONI DI MARMO DI CARRARA

An integrated analytical approach can be useful to study the effectiveness of preservation treatment for Carrara marble surfaces, carried out for testing commercial products which are based on nano-structured silica oxides. Variation in hydrophobic properties, porosity distribution, and chemical composition of treated surfaces have been studied. With this aim, contact angle evaluation, NMR, XRF measurements have been used. Changes of above mentioned physical and chemical characteristics have been evaluated before and after aging in saline chamber of the treated and untreated samples. Moreover, the effectiveness of ultrasonic treatment in “safe” removal of the products from treated surfaces …

Characterization of foxing stains in early twentieth century photographic and paper materials

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 …

Dating of a sediment core in the Palermo Bay (Sicily, Italy)

An extensive study of sediment cores in the Palermo Bay has been carried during the last two years. Main goal of the research was to study the environmental pollution of the area, using foraminifers as an environmental indicator.

PRODOTTI NANOSTRUTTURATI PER LA PROTEZIONE DI SUPERFICI LAPIDEE: VALUTAZIONE DELL’EFFICACIA MEDIANTE TECNICHE FISICHE NON INVASIVE

The use of nanoproducts in the Cultural Heritage (CH) field requires great sensitivity and responsibility and, above all, analytical research and studies evaluating effectively their potential use. In order to evaluate the capability of nanostructured protective in the CH field, limestone materials of historical-artistic interest were treated and then studied. The study focuses on the non-invasive evaluation of samples stone, of interest in the CH field, their surface has been tested with nanostructured products. In particular, samples of limestone of Favara (Sicily) have been studied, before and after artificial aging. The analytical methodology involved X-ray fluorescence measurements, in…

Preparation and Characterization of Gold Nanorods Coated with Gellan Gum and Lipoic Acid

Gold nanorods (AuNRs) can combine therapeutic hyperthermia with diagnostic features, representing a smart choice to address personalized cancer treatments. In this regard, a crucial quest is the selection of the right biocompatible coating agent able to stabilize them in the physiological environment, further endowing the possibility to load bioactive molecules and/or targeting moieties. Therefore, AuNRs optical properties can be successfully merged with advantageous materials features to obtain selective photothermal therapy (PTT) systems. Here, the natural materials lipoic acid (LA) and the polysaccharide gellan gum (GG) were chosen to prepare three types of stabilized gold nanorods, usin…

Complementarity of the XRF and LIBS analyses in the conservation science: the case studies of the bronze alloys

The present study confirms how the integrated use of non-destructive or micro-destructive spectroscopic techniques are capable to provide a clear response to the investigative needs in the conservation science. In particular, the X-ray fluorescence analysis in association with laser-induced breakdown spectroscopy can be useful for collecting information about chemical composition and elemental stratigraphic distribution of the external layers. The complementarity of these techniques has been tested by analysing bronze samples, made in the laboratory according to binary, ternary and quaternary alloys, typical of Roman archaeometallurgical production and buried for one year. The findings have…

Preliminary data on correlations between aberrant benthic foraminifera and metal concentrations in sediments from Palermo and Termini gulfs (Sicily)

Response of benthic foraminifera to heavy metal contamination in marine sediments (Sicilian coasts, Mediterranean sea)

To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By c…

EPR ANALYSIS OF ALANINE WITH GADOLINIUM FOR DOSIMETRY AT TRIGA MARK II REACTOR OF MAINZ

Negli ultimi anni il crescente interesse verso la radioterapia a cattura neutronica (internazionalmente nota come Neutron Capture Therapy - NCT) per il trattamento di neoplasie ha stimolato diverse attività di ricerca finalizzate alla caratterizzazione del fascio utilizzato e all'ottimizzazione delle procedure radioterapiche. La corretta riuscita del trattamento NCT e il monitoraggio della dose impartita non possono prescindere dalla valutazione delle varie componenti del fascio impiegato (neutronica e fotonica). Infatti, durante le procedure di moderazione dei neutroni, si verifica la produzione di fotoni e la stima dei rischi a cui sono soggetti i tessuti sani sottoposti al campo misto ne…

NMR relaxometry measurements of Fricke gel dosimeters exposed to neutrons

Fricke infused gel matrices offer several features making them suitable for dosimetric applications; among the set here are tissue equivalence, low cost and ease of preparation. Their nuclear magnetic resonance (NMR) relaxation properties can be used as a radiation detector for the dosimetry of beams used in cancer therapy. In recent years neutron capture therapy has been resumed for the treatment of various types of cancer and it requires three-dimensional mapping of the neutron fields. In this work, we investigated this particular application through NMR relaxometry and MR imaging of Fricke gels exposed to neutrons. We analyzed both the R1 and R2 relaxation rates, which relate to the long…

Diffusion and sensitivity characteristics of a chemically cross-linked PVA-Fricke gel dosimeter

Comparison of LIBS and micro-XRF measurements on bronze alloys for monitoring plasma effects

The laser-induced breakdown spectroscopy (LIBS) technique is often used as atomic spectroscopic technique for elemental analysis of materials. However, it presents some drawbacks that make an accurate quantitative analysis difficult. Since the plasma properties, such as spatial inhomogeneity and plume stoichiometry strongly depend on the experimental conditions, the measurements are less reproducible. In order to evaluate the measurement fluctuations, we propose to use the more established micro X-Ray fluorescence (μ-XRF) technique for validating LIBS data. In particular, the quantitative data, obtained by varying the laser fluence, the shot numbers and the temporal acquisition parameters, …

Agarose and PVA Fricke gel dosimeters exposed to clinical photons beams: Nuclear Magnetic Resonance Relaxometry and Imaging

Fricke Xylenol Gel (FXG) dosimetric system is based on the radiation induced oxidation of ferrous (Fe2+) to ferric (Fe3+) ions. The application of Fricke gels for ionizing radiation dosimetry is continuously increasing worldwide due to their many favorable properties. However, one of their shortcomings is that ferrous and ferric ions diffuse in the gel matrix. To maintain the spatial integrity of the dose distribution, Fricke gels must be undergoing measurement within a few hours of their irradiation, so that ferric ions remain close to their point of production. Thus, the spatial integrity of the dose distribution in the Fricke gel is maintained. The gel matrix also contributes to the oxid…

Caratterizzazione NMR ed EPR di mattoni del Teatro Antico di Taormina.

Dependence of MRI sensitivity of Fricke gel dosimeters exposed to clinical photons beams on ferrous ammonium sulfate content

Heavy metals analysis by non invasive techniques for fish food quality control

Metodologie spettroscopiche integrate per la caratterizzazione dei prodotti di corrosione nei bronzi archeologici

Mosaic floors of roman Villa del Casale: Principal component analysis on spectrophotometric and colorimetric data

Abstract Spectrophotometric and colorimetric data obtained during a measurement campaign aimed at supporting the Roman "Villa del Casale" (Piazza Armerina, Sicily, Italy) conservation activities, are presented. Special attention was paid to the possible variation of the chromatic coordinates, possibly due to the interventions of cleaning, consolidation, and protection. Data have been analyzed by the Principal Component Analysis (PCA) statistical technique, with the attempt to investigate its role in data variability reduction and verify its effectiveness in interpreting the phenomena occurring on the mosaic surface of the Villa, through grouping the observations into homogenous clusters. Ef…

Chemistry, mineralogy and radioactivity inposidonia oceanicameadows from North-Western Sicily

This paper presents measurements of major, minor, metal trace elements and radionuclides in sediments and in Posidonia oceanica samples from north-western Sicily (Italy). The mineralogical and chemical composition of sediments were determined by X-ray diffraction and X-ray fluorescence techniques, respectively. A flame atomic absorption spectrophotometry was used to measure concentrations of Cu, Zn, Cd and Pb in P. oceanica samples and in sediments. Specific activities of selected radionuclides have been determined by high-resolution gamma spectrometry. Standard statistical analysis was used to assess correlations between different elements and different sample types.

Comparison of EPR response of alanine and Gd2O3-alanine dosimeters exposed to TRIGA Mainz reactor.

In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of…

Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages. A comparison with micro-X-ray fluorescence analysis

Gilding and pigments of Renaissance marble of Abatellis Palace: non-invasive investigation by XRF spectrometry

Most of the artworks constituting the collection of Renaissance statuary of Abatellis Palace in Palermo (Sicily) show evidence of colour layers and fragments of gold foil that probably once covered the whole marble surface. The restoration of some of these statues has allowed to carry out archaeometric studies about the painting technique and to highlight the original materials and inclusion present on the precious marbles by two famous Italian sculptors of the Renaissance, Francesco Laurana and Antonello Gagini. The measurements have been performed in situ through the integrated use of two non-invasive techniques: visible fluorescence stimulated by ultraviolet light and X-ray fluorescence.…

ANALISI CHIMICO-TOSSICOLOGICA E CHEMIOMETRICA DI SEDIMENTI MARINO COSTIERI SICILIANI

Nuove metodologie per la valutazione dello stato di inquinamento dell'ambiente marino

A comparison among different techniques for human ERG signals processing and classification

A comparison among different techniques for human ERG signals processing and classification ( Articles not published yet, but available online Article in press About articles in press (opens in a new window) ) Barraco, R.a, Persano Adorno, D.a , Brai, M.a, Tranchina, L.b a Dipartimento di Fisica e Chimica, Università di Palermo and CNISM, Viale delle Scienze, Ed. 18, I-90128 Palermo, Italy b Laboratorio di Fisica e Tecnologie Relative - UniNetLab, Università di Palermo, Viale delle Scienze, Ed. 18, I-90128 Palermo, Italy Abstract Feature detection in biomedical signals is crucial for deepening our knowledge about the involved physiological processes. To achieve this aim, many analytic appro…

Dating of a Sediment Core by 210Pbex Method and Pb Pollution Chronology in the Palermo Gulf (Italy)

Within a more general study on marine sediments in the Gulf of Palermo (Sicily, Italy), the 210Pbex dating method (using a model with constant sedimentation rate) has been applied to one sediment core. The main goal of the research was to study the Pb pollution chronology. Dating of the core has allowed evaluating the time evolution of the gulf lead concentrations. Specific activities of 137Cs have also been measured in the sediment core sections as an independent confirmation of the chronology derived by the 210Pbex method. The time scale has then been used to correlate lead concentrations in core sections to estimated lead emissions in air due to gasoline combustion. A good correlation be…

Nanostructured products applications for the conservation of Cultural Heritage samples

Qualitative and quantitative characterization of historical pigment mixtures through non-invasive techniques

Applicazione di tecniche e materiali innovative per la conservazione ed il restauro di materiali lapidei

Relationship among anthropogenic pollution, benthic foraminifera assemblages and their morphological deformations from marine sediments of the Sicilian coast (Southern Italy)

Analisi NMR su gel di tipo Fricke irradiati con fasci routinari per la radioterapia: stabilità e sensibilità in funzione degli additivi

In questo lavoro sono presentate le misure effettuate tramite rilassometria NMR su campioni costituiti da una matrice gelatinosa drogata con ioni ferrosi comunemente chiamati dosimetri gel di tipo Fricke (FXG). La dosimetria con gel Fricke si basa sulla ossidazione degli ioni ferrosi (Fe2+) in ioni ferrici (Fe3+) all’interno di una matrice gelatinosa a seguito di irraggiamento (Schreiner, 2004). Tale processo è fortemente dipendente dalla dose somministrata (Marrale, 2014a). I dosimetri di Fricke sono tessuto-equivalenti, rispondono ad ogni tipo di radiazione ionizzante ed, assumendo la forma del contenitore in cui avviene la gelificazione, possono essere utilizzati per studiare l’effetto d…

ESR response to 60Co-rays of ammonium tartrate pellets using as additive

Abstract This work presents experimental results regarding a new ammonium tartrate blend for ESR dosimetry, with a higher sensitivity and a lower lowest detectable dose (LDD) to Co 60 γ -rays than the recently used pure ammonium tartrate. The blend composed by ammonium tartrate and gadolinium-oxide ( Gd 2 O 3 ) shows a greater sensitivity ( ∼ 2 times) and a smaller LDD than ammonium tartrate. The increased sensitivity was mainly attributed to the great atomic number ( Z = 64 ) of gadolinium, that increases the effective atomic number of the blend; the interaction probability with photons and consequently the radical yield is therefore enhanced. Moreover ammonium tartrate with Gd 2 O 3 has a…

Double Laser LIBS and micro-XRF spectroscopy applied to characterize materials coming from the Greek-Roman theater of Taormina

The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown, in recent years, its great potential for rapid qualitative analysis of materials. The possibility to implement a portable instrument that perform LIBS analysis makes this technique particularly useful for in situ analysis in the field of cultural heritages. The aim of this work is to compare the results, obtained by LIBS measurements with X-Ray Fluorescence (XRF) ones, on calcareous and refractory materials coming from the Greek-Roman theater of Taormina. Calibration curves for LIBS and XRF were obtained by measuring certified reference materials and using them as standards. LIBS measurements we…

ESR RESPONSE TO 60 CO-RAYS OF AMMONIUM TARTRATE PELLETS USING GD2O3 AS ADDITIVE.

This work presents experimental results regarding a new ammonium tartrate blend for ESR dosimetry, with a higher sensitivity and a lower lowest detectable dose (LDD) to 60 Co -rays than the recently used pure ammonium tartrate. The blend composed by ammonium tartrate and gadolinium-oxide (Gd2 O3 ) shows a greater sensitivity (∼2 times) and a smaller LDD than ammonium tartrate. The increased sensitivity was mainly attributed to the great atomic number (Z = 64) of gadolinium, that increases the effective atomic number of the blend; the interaction probability with photons and consequently the radical yield is therefore enhanced. Moreover ammonium tartrate with Gd2 O3 has a linear dose respons…

Trace metals in “Posidonia oceanica” seagrass from south-eastern Sicily

Heavy-metal concentrations were measured in sediments and tissues of Posidonia oceanica seagrass from south-eastern Sicily (Italy) in order to assess the degree of metal pollution in the coastal area. Seagrasses and sediments were collected at four sites along the south-eastern coast of Sicily. Flame atomic absorption spectrophotometry (FAAS) was used to measure concentrations of Cu, Zn, Cd and Pb. Standard statistical analyses were used to assess significant differences among the levels of the elements measured in different tissues and sediment and spatial distribution. The greatest values of potentially toxic metal concentrations were observed at the station near the industrial sites of A…

XRF analysis to identify historical photographic processes: The case of some Interguglielmi Jr.’s images from the Palermo Municipal Archive

Abstract 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 ph…

Posidonia oceanica as a Historical Monitor Device of Lead Concentration in Marine Environment

We show that Posidonia oceanica is able to reliably monitor the variability of environmental lead (Pb). We analyze lead concentration measured in the scales and rhizomes of Posidonia oceanica collected in seven sites along the coasts of the Sicily island and subsequently fractioned them according to a lepidochronological analysis. We measure lead concentration in Posidonia oceanica tissues by using the flame atomic absorption spectrophotometry technique. We compare the measured lead concentration with the estimated lead emission in air due to the gasoline sold and used for combustion in car engines in Sicily. By computation of the Pearson cross-correlation coefficient, we show that lead con…

In vivo efficacy of verteporfin loaded gold nanorods for combined photothermal/photodynamic colon cancer therapy.

The high incidence of cancer recurrences and the frequent occurrence of multidrug resistance often stem from a poorly selective and inefficient antineoplastic therapy, responsible for the onset of undesired side effects as well. A combination of minimal-invasive approaches could thus be a useful strategy to surmount these shortcomings, achieving a safe and solid cancer therapy. Herein, a multi-therapeutic nanotool was designed by merging the photothermal properties of gold nanorods (AuNRs) with the photodynamic activity of the photosensitizer ver-teporfin. AuNRs were coated with the natural materials lipoic acid and gellan gum (AuNRs_LA,GG) and subse-quently loaded with verteporfin (AuNRs_L…

Application of the ESR spectroscopy to estimate the original dose in irradiated chicken bone

Abstract The paper discusses the results of an investigation aimed to use the ESR spectroscopy as a quantitative procedure to estimate the original dose in irradiated chicken. The time stability of the ESR signal was at first carried out, to obtain a correction factor to be applied to the dose estimated with the added dose method. Our results show that this procedure gives an estimation of the original dose within ±25%.

An EPR method for discriminating radiation beams in ammonium tartrate and tooth enamel

The radiation linear energy transfer (LET), which is the energy released by ionizing radiation per path unit, arouses great scientific interest because the biological damage produced by ionizing radiation in tissues is strictly related to LET. Radiation beams with different LETs will cause different spatial energy distribution and therefore different effects inside matter. In the last twenty years the EPR spectroscopy has become a valuable dosimetric tool. This technique allows absorbed dose measurements through the detection of free radicals produced by ionizing radiation in organic and/or inorganic compounds. In this work we have analyzed the possibility of using the acquisition of two co…

Ottimizzazione della dosimetria a termoluminescenza per la identificazione di spezie ed erbe aromatiche irradiate

Mural salts characterization of "Penitenziati" mural paintings in Chiaramonte Palace (Palermo)