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This paper aims at assessing the use of nanomaterials in painting conservation and in cleaning practices that could be alternative to the traditional ones to overcome the limits of new green materials. Titanium dioxide nanoparticles have been spread and studied on historical painting surfaces with good results. In particular, the properties of TiO2 nanoparticles have been considered useful for self-cleaning and protective purposes against the accumulation of dirt and dust that represents the first phase in deterioration of historical painting surfaces. TiO2 nanoparticles, prepared in distilled water by Pulsed Laser Ablation in Liquids, were applied on painting mock-ups realized in the laboratory according to old recipes and using historical binders and pigments. The surface characteristics of the painting were investigated by contact angle measurement and by Atomic Force Microscopy. The optical and aesthetical compatibility of the colloidal dispersions with the painting was assessed by spectrophotometry, and then the cleaning efficiency was evaluated by discoloration of a dye under ultraviolet irradiation, at fixed time intervals, using colorimetric technique. Because of the high reactivity of nanoparticles, the possibility of degrading the painting surface, together with the chromatic marker, was examined by colorimetric measurements. The evaluation of the color changes is important for all the materials belonging to cultural heritage, especially painting, for which the color modification induced by protective and/or cleaning interventions could irremediably compromise the work of art.

Multiple brain metastases single-isocenter stereotactic radiosurgery (SRS) treatment is increasingly employed in radiotherapy department. Before its use in clinical routine, it is recommended to perform end-to-end tests. In this work, we report the results of five HyperArc

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To evaluate the influence of a different order of dentin and enamel layers on stratification appearance of different resin composites. 144 Dentin (D) and Enamel (E) composite samples (Clearfil Majesty ES-2 Premium, Brilliant EverGlow, Estelite Asteria), 1 mm thick, were divided into 12 configurations for each composite, with Enamel-Dentin-Dentin-Enamel (EDDE) assumed as target. The colour specification was conducted using a spectrophotometer, elaborating the results with the CIE L*a*b* colour coordinates and calculating the colour difference in terms of [Formula: see text] quantity. A value of this last major of 3.3 was considered not clinically acceptable. Moreover, data were analyzed using two-way analysis of variance and Tukey post hoc test (P 0.05). For Clearfil Majesty ES-2 Premium and Brilliant EverGlow, six configurations showed [Formula: see text] 3.3 compared to gold standard EDDE. [Formula: see text] was influenced especially by b* and L* coordinates (P 0.05). EDED showed no visual difference (0 [Formula: see text] 1.1) for both composites. For Estelite Asteria, two configurations reported [Formula: see text] 3.3 compared to EDDE. In particular, the L* coordinate influenced [Formula: see text] results (P 0.05). EDDD was the best configuration (0 [Formula: see text] 1.1). Within the limits of a vitro study, Brilliant EG showed more dependence from order and thickness of stratification (resulting more similar to Clearfil Majesty ES-2 Premium); therefore, it could be indicated for more complex aesthetic restorations. Estelite Asteria seems to be able to balance small differences in thickness of dentin and enamel layers, and consequently, it is more indicated to different clinical situations.

The exploitation of a plant-based sensor, able to measure ultraviolet radiation intensity with wavelength of UV-A band (315–400 nm) is here proposed. The approach presented arouses interest in the context of the realization of sensing devices and novel measurement systems green, non-toxic, environmentally friendly, low-cost and disseminable. The working principle is based on the use of natural sensing properties to UV-A radiation of the plant and its metabolic process in order to respond to the received UV intensity. The device is composed of Dimorphotheca ecklonis, which is a particularly sensitive plant to the physical quantity of interest and two implanted electrical contacts to convert, through a chemo-electrical process, the measurand into an output voltage across the electrodes. A suitable experimental setup has been developed and a LabVIEW™ routine has been used for the acquisition of the signal. Experimental results and the characterization of the plant-based sensor show the suitability of the proposed method which is able to work in absence of batteries making the system interesting for several intriguing applications.

The research concerns the study of a device composed of two electrical contacts with the soil inside a container that showed good potentialities as transducer based on chemo-electrical principle typically used for biological fuel cell and green sensors. The main objective of the work here presented is the correlation between the content of microorganisms of the soil and the response in terms of voltage generation. To accomplish this task, the measurements have been performed considering the output response of a soil as a function of energy radiation doses. As standard reference, soils were also sterilized by heat. Particular emphasis is given to the reduction of the microbial activities in the soil using different dose values and temperature values considering the correlation with the output signal. The measurements campaigns here addressed demonstrate the suitability of the transduction principle for the design of suitable green devices useful for the realization of transducer and sensing systems.

Detectors are a key feature of the contemporary scientific approach to cultural heritage (CH), both for diagnostics and conservation. INFN-CHNet is the network of the Italian National Institute of Nuclear Physics that develops and applies new instrumentation for the study of CH. This process results in both optimized traditional state-of-the-art and highly innovative detection setups for spectrometric techniques. Examples of the former are X-rays, gamma-rays, visible-light and particles spectrometers tailored for CH applications, with optimized performances, reliability, weight, transportability, cost, absorbed power, and complementarity with other techniques. Regarding the latter, examples are ARDESIA, the array of detectors at the DAΦNE-Light facility, the MAXRS detection setup at the Riken-RAL muon beamline and the imaging facilities at the LENA Laboratory. Paths for next-generation instruments have been suggested, as in the case of the X-ray Superconductive Detectors and X-ray Microcalorimeter Spectrometers, allowing astonishing improvement in energy resolution. Many issues in CH can now be addressed thanks to scientific techniques exploiting the existing detectors, while many others are still to be addressed and require the development of new approaches and detectors.

This paper is aimed at studying different pottery sherds excavated in the site of Valcorrente, located in Sicily, occupied in three main periods, dating respectively to the end of the Neolithic period, to the end of the Chalcolithic period, and to the Early Bronze Age. The chemical composition of the pottery sherds has been analysed with Ion Beam techniques at AGLAE facility at Centre de Recherche et Restauration des Musées de France and the results have been treated with principal component analysis in order to extract indications about the ceramic production technology in the area and the evolution in time.

Cutting efficiency of Reciproc R25 (REC) and Reciproc blue R25 (REB) at different inclinations was evaluated. Sixty new files were tested at 90°, 70° and 45° of inclination in relation to the sample (n = 10), using a customised machine. All files were activated in reciprocation against standardised gypsum blocks for 120 s. Cutting efficiency was determined by measuring the block weight loss with an analytical balance and measuring the length of the block surface cut using a digital calliper. Data were statistically analysed (two-way ANOVA, Bonferroni t-test) with the significance level set at P < 0.05. There was no difference for REC among the tested angles. REB had no statistical difference between 90° and 70°; however, its cutting efficiency significantly increased at 45°. There was a significant difference between REC and REB at 45° only. Under these conditions, increased file inclination to 45° and blue heat treatment improved cutting efficiency of reciprocating files.

Color specification is the process of measuring the color of a sample in a given color space. We focused onto the Munsell color space as archaeologists are used to employ the so called Munsell Soil Color Charts (MSCCs) directly in the excavation sites. For these scholars and researchers, being enabled to perform Munsell color specification in an automatic way is crucial, as they spend a lot of time to subjectively specify colors in the Munsell system. We extended the dataset ARCA328, which was specifically thought for the automatic Munsell color specification issue, increasing the number of images from 328 to 1,488, and the number of samples from 56,160 to 315,333. Then, we conducted generalization-tests of color conversion for color specification, adopting a classification approach instead of a regression one. This choice was motivated by the fact that the set of all the possible HVC coordinates in the MSCCs is a discrete one. Hence, we decided to consider each chip in the MSCCs as a class to be learnt and recognized by the SVC. With these tests we highligthed the limits of automatic Munsell color specification without any reference-system or calibration phase. Finally, we gave insights for future works aimed to design automatic illuminant calibration phase and to investigate deep learning approaches, leveraging a synthetic images rendering procedure we also present in this work.

Munsell Soil Charts are a very common tool used by archaeologists for the color specification task. Charts are usually employed directly on cultural heritage sites to identify color of soils and collected artifacts. However, charts are designed to be used specifying the color through subjective perception of users, by visual mean, in a time-consuming and error-prone procedure. It is likely that two users may estimate different Munsell notations for the same specimen, as colors are not perceived uniformly by different people. Hence, estimation process should be repeated several times and by more than a single expert user to be considered reliable. In this work, we employ our framework, Automatic Recognition of Color for Archaeology (ARCA), specifically designed to provide a method for objective, deterministic, fast, and automatic Munsell estimation. ARCA is a valuable asset for archaeologists as it provides the definition of a smooth pipeline for an affordable Munsell notation estimation: image acquisition of specimens with general purpose digital cameras in an uncontrolled environment, manual sampling of specimen images in the ARCA desktop application, automatic Munsell color specification, and report generation. We further assess our method with improved color tolerance validations and evaluations, introducing a comparison between Δ E 00 , Δ E 76 , Δ L *, Δ a *, and Δ b * differences. One of the main contributions of this article is the extension of our former dataset ARCA108. We gathered two additional sets of images obtaining a new dataset consisting of pictures of Munsell Soil Charts Editions 2000 and 2009 plus images from a real test case with 16 pottery shards. The new dataset counts 56,160 samples and 328 images, so it has been called ARCA328. Experimental results are reported to investigate which could be the best configuration to be used in the acquisition phase.

The main goal of the paper is the optical and colorimetric characterization of the pigment mixtures realized with pure pigments of the principal artist's hues and white pigments through spectrophotometric analysis. This research work represents a first step in a methodology study aimed to the verify potentialities and limits of spectrophotometric techniques in the identification of pigments in mixtures. The analysis regarded the trend of Spectral Reflectance Factor (SRF%) in visible spectrum and of the derivative of SRF, d(SRF%). In particular, the analysis of d(SRF%) of the mixture in the function of achromatic pigment concentration has the aim of highlight shift of the extrema points in relation to the relative quantities of the mixture components. To this aim, painting samples were prepared in laboratory mixing the coloured pigments with achromatic ones in variable weight concentration from 10% to 90% for each of the components. This is necessary to evaluate the minimum quantities of white that could change the coloured pigments SRF% spectra. Also the analysis of colour coordinates is performed to put in evidence the L*, a*, b* trend in CIELAB 1976 space.

Cross-dating of bricks and mortars from historical building, through thermal (TL) and optically stimulated (OSL) luminescence have achieved good accuracy and precision. However this approach is, in many cases, not exhaustive especially for buildings with different construction phases closely temporally spaced to each other. The uncertainties of experimental data added to the reuse of old bricks and/or the presence of mortars applied on restorations represent the main limits to obtain the complete chronology. In the case of the Convento de S. Francisco (Coimbra, Portugal), the dating results were crossed with the stratigraphic study of the building, mineralogical characterization by XRD and colorimetric data of the mortar samples. Thanks to luminescence ages, mineralogical composition and color specification, two phases of construction were identified: the first from the 17th century and the first half of the 18th century and the second from the second half of the 18th century to the first half of the 19th century. These results were confirmed by mineralogical characterization and colorimetric measurements of mortars that identify two different types of materials in aggregate/binder ratio terms and superficial optical characteristics.

In the study of archaeological ceramics, it is important to have compositional data to identify their origin and source. The fabric also provides useful information on the production technology, especially with regard to the firing steps. The work presented here is connected to this field and focuses on the main parameters related to the terracotta artefacts preparation. Thus, one can consider the effects in terracotta characteristics of different raw materials and firing parameters, in particular for pottery of Caltagirone, which is one of most important centres of pottery production in Italy, active since the Neolithic. To this end, terracotta samples have been reproduced in a laboratory setting according to the ancient procedure of Caltagirone manufacture, starting from clay and degreaser extraction in local historical sites. The analysis was conducted using a portable X-Ray Fluorescence (pXRF) spectrometer for elemental characterization of sand degreaser and of clays during each step of the realization process and in different firing conditions. SEM-ED techniques were also employed to verify the method and results for some of the samples after firing process. Framing the technological context of manufacture production, known in the specific case, it is also possible to identify potential outcomes and limits in the study of potsherds using pXRF technology, in applying the methodology to historic artefacts.

The colour of a paint layer is determined by the pigments mixed with a vehicle and painted on a support. According to their chemical nature, the vehicles are substances that, after drying or hardening, produce an uniform and homogeneous layer. With the aim of quantifying the influence of the medium on the specification of the painting colour, we realized samples of paintings. We considered pigments and dyes of the artist's hues using the vehicles typical of ancient times: oils (especially linseed and poppy oils), casein and egg yolk, mixed according to old recipes. Measurements were performed by reflectance spectrophotometry observing the Spectral Reflectance Factor (%SRF) trend and calculating colour changes. The colorimetric study was carried out in the CIELAB colour space related to the CIE 1964 standard observer and with the D65 illuminant. The results were evaluated also on the basis of the distribution of pigment particles on paint layers observed by scanning electron microscopy.

Accurate color reproduction in conservative dentistry is fundamental to the aesthetic success of the restorations. The need to specify the color objectively has been known for some years, and this article aims to make a contribution to this field. This work is part of a multidisciplinary research project, and it has a double aim. The first purpose was to measure the color differences between the two new composite resin restorative materials and the most used dental color scale. Measurements show some differences from color shades indicated by the manufacturers and those obtained from experimental data. The influence of different order of enamel and dentin layers on color perception was also investigated to evaluate clinical strategies useful to obtain desired result. Relevant differences are observed in the stratification of dentin and enamel discs especially for one of the two studied composites.

The historical pigments, contrary to modern ones, are not constituted by particles having all the same size and this influences the colour of the paint layers. The hiding power and colouring power of a pigment depends, in fact, on its particle size. The aim of this study was to evaluate the influence of particle size on optical characterization of paintings in terms of reflection of light and related colour specification. Starting from the qualitative observation, we have attempted to quantify the pigments colour variations induced by grinding and then attributable to granularity. Powdered pigments of principal colours have been selected in specific particle size range by mechanical sieving. The measurements were performed both on pigment pellets and on paintings realized with binder casein. All samples were characterized by an optical and colorimetric point of view through spectrophotometric analysis and for the surface morphological observation through scanning electron microscopy. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 236–243, 2017

The main approach to differentiated thyroid cancer (DTC) therapy is still empiric, consisting of the administration of fixed activities. Repeated treatments, however, may have a stunning effect. An individualized dosimetric study may represent an important tool to determine the best activity to prescribe, in particular for patients with distant metastases or when therapy with recombinant human thyroid-stimulating hormone (rhTSH) stimulation is deemed necessary. This study provides a practical operational example for carrying out a dosimetric study, according to the European Directive EURATOM/59/13. Starting from the case of a patient who underwent rhTSH stimulation before radioiodine ablation, we illustrate the necessity of measuring both red marrow (RM) and blood (BL) absorbed dose during the treatment in order to not exceed the dose limit of 2 Gy to the RM, so as to avoid repeating radioiodine treatment several times. Dosimetry to the RM and BL was performed during the treatments, after administration of therapeutic activity without modifying the fixed activity schema, using different approaches. The results suggest the possibility of restricting the number of treatments, reducing thus the risk of stunning effect and, where possible, eliminating an additional source of stress and dejection for patients.

To compare the cutting efficiency of several glide path files: HyFlex EDM Glidepath File (HEGF), One G (OG), R-Pilot (RP) and WaveOne Gold Glider (WOGG) at different cutting inclinations.Cutting efficiency of 120 new HEGF, OG, RP and WOGG was tested at 90°, 70° and 45° inclination in relation to the sample. Depending on manufacturer instructions, instruments were tested in continuous rotation or reciprocating motion against standardized gypsum samples for 120 s using a customized apparatus. Cutting efficiency was determined by measuring the weight loss and the length of the sample cut. Data were analysed using two-way analysis of variance and Tukey t-test (P 0.05).RP and WOGG had greater cutting ability than HEGF and OG in all tested angles. RP tested at 45° had significantly greater cutting efficiency than when tested at 90° and 70° (P 0.05). OG was not significantly different in terms of cutting ability at 90°, 70° and 45° (P 0.05). HEGF and WOGG had significantly greater cutting efficiency at 45° and 70° compared to 90° (P 0.05), with no significant difference between 45° and 70° (P 0.05). RP had the greatest cutting ability at all tested angles.Reciprocating glide path instruments had greater cutting efficiency compared to those in continuous rotation. An inclined insertion (45° or 70°) increased the cutting ability of glide path files except for One G conventional NiTi files.

The patient dose in radiodiagnostic is currently monitored through an ionizing radiation exposure index named Volume Computed Tomography Dose Index (CTDIvol) and the Dose-Length Product (DLP), displayed by CT scanner and measurable through a 100 mm long pencil ionization chamber, inserted in a homogeneous cylindrical PMMA phantom. The phantom is 14 cm long and has a diameter of 16 (32) cm that represents the adult head (body). One of the main flaws of such a method is that it does not return any information on the dose distribution to organs, and the average absorbed dose value, due to the material and dimensions of both the phantom and the ionization chamber, might be either underestimated or overestimated depending upon the patient size. With the aim to obtain complementary information, this work presents a method to estimate organ dose in the thoracic area of an anthropomorphic woman phantom in CT, by employing GafchromicTM XR-QA2 and computational 3-D reconstruction methods. Lungs, heart, and spinal cord have been chosen as a dosimetry case study. XR-QA2 films have been placed between the phantom slabs in the thoracic area and scanned with a multi-slice CT scanner. 2-D and 3-D absorbed dose distributions for each organ have been analyzed, by means of a custom code in Matlab®. Critical aspects in the dose distributions have been found for the spinal-cord case (serial organ) where the dose distribution is non normal and the maximum dose value is ~ 30 mGy while a maximum dose value between 26 and 28 mGy has been measured elsewhere.