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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 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 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.

Ultrasonic devices disperse less energy in the tissues. The new Harmonic Focus+ (HF+) seems to be more efficient but thermal damages have been reported. This study examined the temperature and the emissivity profile of the active and passive blades of the HF+, on a pig tissue model at different power settings. The FLIR System B series thermal imaging camera has been used on various biological pig tissues to evaluate the emissivity of the ultrasonic device. The active blade heats up faster than the passive one and the increase in power increases the speed of the temperature raising only on the active blade. Increasing the power setting reduces the dissection time and the temperature of both blades. Active blade temperatures of

The European Directive 2013/59/Euratom focuses on the radiation protection and patientdosimetry. In particular, the dose absorbed by serial organs such as the spinal cord due to diagnosticexams plays a crucial role in the appraisal of medical exposure. In this work, a comparison betweendose measurements performed with GafchromicTM XR-QA2 and TLD 100H is presented. Thedosimeters&mdash, after a calibration procedure through an X-ray tube&mdash, were placed within the thoraxregion of an anthropomorphic phantom corresponding to the spinal cord area exposed to a thoracicCT procedure. The mean-dose value was measured with GafchromicTM first, and it was thencompared to the dose value obtained with TLDs, resulting in a good agreement between the twodosimetric methodologies. Additionally, the results showed that&mdash, due to the usage of the automaticexposure control (EC) system&mdash, the discrepancy between the two methods is proportional to thecurrent output of the CT system

The study is aimed at a verification of dose changes for a computed tomography automatic tube-current modulation (ATCM) technique. For this purpose, anthropomorphic phantom and Gafchromic® XR-QA2 films were used. Radiochromic films were cut according to the shape of two thorax regions. The ATCM algorithm is based on noise index (NI) and three exam protocols with different NI were chosen, of which one was a reference. Results were compared with dose values displayed by the console and with Poisson statistics. The information obtained with radiochromic films has been normalized with respect to the NI reference value to compare dose percentage variations. Results showed that, on average, the information reported by the CT console and calculated values coincide with measurements. The study allowed verification of the dose information reported by the CT console for an ATCM technique. Although this evaluation represents an estimate, the method can be a starting point for further studies.

The present study was aimed at verifying the automatic registration of the Focal (Elekta) platform with a dedicated phantom. A phantom that simulates the pelvis region in a stylised way and finalised to the registration of computed tomography–magnetic resonance images was designed and realised. After acquiring the two sets of images, the registration was performed both in automatic and manual mode to verify whether they were comparable. To test the repeatability of the automatic registration, some known rigid transformations were imposed to the original images. If the registration method works correctly, parameters which bring the images into alignment must always be the same. Automatic registration performed by the software did not prove satisfactory, whereas if a specific tool [volume of interest (VOI) tool] allowing the calculation to be limited to the landmark region was used, the registration parameters were comparable with those of the manual registration. Regarding the repeatability of the automatic registration, the software brought the images in the correct alignment performing translations and rotations along the longitudinal axis up to 40°, while it was not satisfactory for rotations along the transverse axes. The experimental results showed that in clinical application automatic registration is reliable if the VOI tool that includes visible landmarks in both studies is used. However, because the algorithm did not prove sensitive to rotations along the transverse axes, the position of the patient during the examinations plays a crucial role.