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In breast cancer (BC) care, radiotherapy is considered an efficient treatment, prescribed both for controlling localized tumors or as a therapeutic option in case of inoperable, incompletely resected or recurrent tumors. However, approximately 90% of BC-related deaths are due to the metastatic tumor progression. Then, it is strongly desirable to improve tumor radiosensitivity using molecules with synergistic action. The main aim of this study is to develop curcumin-loaded solid nanoparticles (Cur-SLN) in order to increase curcumin bioavailability and to evaluate their radiosensitizing ability in comparison to free curcumin (free-Cur), by using an in vitro approach on BC cell lines. In addition, transcriptomic and metabolomic profiles, induced by Cur-SLN treatments, highlighted networks involved in this radiosensitization ability. The non tumorigenic MCF10A and the tumorigenic MCF7 and MDA-MB-231 BC cell lines were used. Curcumin-loaded solid nanoparticles were prepared using ethanolic precipitation and the loading capacity was evaluated by UV spectrophotometer analysis. Cell survival after treatments was evaluated by clonogenic assay. Dose–response curves were generated testing three concentrations of free-Cur and Cur-SLN in combination with increasing doses of IR (2–9 Gy). IC50 value and Dose Modifying Factor (DMF) was measured to quantify the sensitivity to curcumin and to combined treatments. A multi-“omic” approach was used to explain the Cur-SLN radiosensitizer effect by microarray and metobolomic analysis. We have shown the efficacy of the Cur-SLN formulation as radiosensitizer on three BC cell lines. The DMFs values, calculated at the isoeffect of SF = 50%, showed that the Luminal A MCF7 resulted sensitive to the combined treatments using increasing concentration of vehicled curcumin Cur-SLN (DMF: 1,78 with 10 µM Cur-SLN.) Instead, triple negative MDA-MB-231 cells were more sensitive to free-Cur, although these cells also receive a radiosensitization effect by combination with Cur-SLN (DMF: 1.38 with 10 µM Cur-SLN). The Cur-SLN radiosensitizing function, evaluated by transcriptomic and metabolomic approach, revealed anti-oxidant and anti-tumor effects. Curcumin loaded- SLN can be suggested in future preclinical and clinical studies to test its concomitant use during radiotherapy treatments with the double implications of being a radiosensitizing molecule against cancer cells, with a protective role against IR side effects.

Does the exposure of magnetic resonance imaging personnel to static magnetic fields fully comply with Directive 2013/35/EU? Despite the obligation to satisfy this question, a general answer cannot be provided, nor are final satisfying good practices methods for exposure assessment currently available. In order to contribute to fix this problem, three different 1.5 T scanners are analysed and – by a new theoretical insight – a positive answer is provided.

Predictive models based on radiomics and machine-learning (ML) need large and annotated datasets for training, often difficult to collect. We designed an operative pipeline for model training to exploit data already available to the scientific community. The aim of this work was to explore the capability of radiomic features in predicting tumor histology and stage in patients with non-small cell lung cancer (NSCLC). We analyzed the radiotherapy planning thoracic CT scans of a proprietary sample of 47 subjects (L-RT) and integrated this dataset with a publicly available set of 130 patients from the MAASTRO NSCLC collection (Lung1). We implemented intra- and inter-sample cross-validation strategies (CV) for evaluating the ML predictive model performances with not so large datasets. We carried out two classification tasks: histology classification (3 classes) and overall stage classification (two classes: stage I and II). In the first task, the best performance was obtained by a Random Forest classifier, once the analysis has been restricted to stage I and II tumors of the Lung1 and L-RT merged dataset (AUC = 0.72 ± 0.11). For the overall stage classification, the best results were obtained when training on Lung1 and testing of L-RT dataset (AUC = 0.72 ± 0.04 for Random Forest and AUC = 0.84 ± 0.03 for linear-kernel Support Vector Machine). According to the classification task to be accomplished and to the heterogeneity of the available dataset(s), different CV strategies have to be explored and compared to make a robust assessment of the potential of a predictive model based on radiomics and ML.

Purpose To investigate the performance of various algorithms for deformable image registration (DIR) to propagate regions of interest (ROIs) using multiple commercial platforms. Methods and materials Thirteen institutions participated in the study with six commercial platforms: RayStation (RaySearch Laboratories, Stockholm, Sweden), MIM (Cleveland, OH, USA), VelocityAI and Smart Adapt (Varian Medical Systems, Palo Alto, CA, USA), Mirada XD (Mirada Medical Ltd, Oxford, UK), and ABAS (Elekta AB, Stockholm, Sweden). The DIR algorithms were tested on synthetic images generated with the ImSimQA package (Oncology Systems Limited, Shrewsbury, UK) by applying two specific Deformation Vector Fields (DVF) to real patient data-sets. Head-and-neck (HN), thorax, and pelvis sites were included. The accuracy of the algorithms was assessed by comparing the DIR-mapped ROIs from each center with those of reference, using the Dice Similarity Coefficient (DSC) and Mean Distance to Conformity (MDC) metrics. Statistical inference on validation results was carried out in order to identify the prognostic factors of DIR performances. Results DVF intensity, anatomic site and participating center were significant prognostic factors of DIR performances. Sub-voxel accuracy was obtained in the HN by all algorithms. Large errors, with MDC ranging up to 6 mm, were observed in low-contrast regions that underwent significant deformation, such as in the pelvis, or large DVF with strong contrast, such as the clinical tumor volume (CTV) in the lung. Under these conditions, the hybrid DIR algorithms performed significantly better than the free-form intensity based algorithms and resulted robust against intercenter variability. Conclusions The performances of the systems proved to be site specific, depending on the DVF type and the platforms and the procedures used at the various centers. The pelvis was the most challenging site for most of the algorithms, which failed to achieve sub-voxel accuracy. Improved reproducibility was observed among the centers using the same hybrid registration algorithm.

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 magnetic resonance relaxometer. Gel samples were exposed to clinical 6 MV photons in the dose range between 0 and 20 Gy. Nuclear magnetic resonance relaxometry measurements were per- formed and the sensitivity to photon beams was measured for various values of the Fe2+ ion concentration. The analyses pointed out that the MR signal increases as the Fe2+ content in- creases and the increase is about 75 % when the concentration of Fe2+ ions is increased from 0.5 mM to 2.5 mM. Furthermore, the sensitivity improvement achieved with increasing the Fe2+ concentration is about 60 %. This paper shows that the portable nuclear magnetic resonance relaxometer used for analysis of porous materials can be used for characterization of these dosimetric gels and this study can be considered as the first step for the characterization of these dosimeters which in future could be used for 3-D dose mapping in clinical applications.

Objective: To report preliminary findings of a phase II study exploring the clinical outcomes of moderate hypofractionated radiotherapy performed with helical tomotherapy (HT) using computed tomography–magnetic resonance imaging–based planning for localized prostate cancer. Methods: The phase II prospective study received ethics approval from our institutional ethics committee. A dose of 60 Gy/20 fractions for low–intermediate risk prostate cancer by means of HT was explored. Primary endpoints of the study were acute and late gastrointestinal (GI) and genitourinary (GU) toxicities. Secondary endpoints were quality of life and biochemical-free survival. Results: A total of 35 patients were included in this interim report. At the time of the analysis, median follow-up was 36 months (range, 13–62). Acute GI toxicity was recorded as follows: grade 1 in 34% and grade 2 in 14%; acute GU toxicity was grade 1 in 71% and grade 2 in 11%. For the entire population of the study, no acute toxicities ⩾ grade 3 occurred. A single case of late grade 3 GU toxicity was registered, whereas no late GI toxicity ⩾grade 3 was recorded. At the time of the final assessment, no biochemical failure was detected. Conclusions: The preliminary results of the present phase II trial, using HT for moderate hypofractionation in localized prostate cancer, are optimal. In fact, HT guaranteed an acceptable tolerability profile with low rates of GU and GI side effects and, more specifically, no acute severe adverse events were recorded. Long-term findings are warranted.

Background: Several experiences in the literature report SBRT as an effective treatment option for medically inoperable early stage non-small cell lung cancer (NSCLC) and oligometastatic disease. The optimal fractionation schedules and total dose remain controversial. In this study, we evaluated the safety in terms of toxicity and efficacy of using of 8–10 fractions schedules with Helical Tomotherapy (HT) for primary and metastatic lung lesions. Methods: Between March 2014 and May 2016, a total of 39 patients (median age 72 years, range 26–91) were treated with HT-SBRT for malignant lung lesions: 22 patients with early stage NSCLC, 17 with oligometastases. Patients received 8–10 fractions with lower daily dose for central and ultracentral lesions. Treatment-related toxicity was evaluated using CTCAE v 4.0 scale. Local control (LC), overall survival (OS) and toxicity rates were prospectively collected. Results: Median duration of RT was 15 days (range 10–26 days) and no interruption occurred. With a median follow-up of 13 months (range 3–29), we reported one G2 pneumonitis (2.6%) and one G2 chest pain (2.6%); no ≥ G2 esophagitis was registered. Actuarial local control rate was 95.5% both at 12 and 24 months for early stage NSCLC and 92.9% both at 12 and 24 months for metastatic patients. OS rate was 94.4 and 92.3% at 1 year, and 94.4 and 83.9% at 2 years in primary and metastatic group, respectively. Conclusions: The use of 8–10 fractions schedule HT-SBRT for lung malignancies results in high LC and OS rates with minimal toxicities reported.

University of Pavia is equipped with a TRIGA Mark II research nuclear reactor, operating at a maximum steady state power of 250 kW. It has been used for many years to support Boron Neutron Capture Therapy (BNCT) research. An irradiation facility was constructed inside the thermal column of the reactor to produce a sufficient thermal neutron flux with low epithermal and fast neutron components, and low gamma dose. In this irradiation position, the liver of two patients affected by hepatic metastases from colon carcinoma were irradiated after borated drug administration. The facility is currently used for cell cultures and small animal irradiation. Measurements campaigns have been carried out, aimed at characterizing the neutron spectrum and the gamma dose component. The neutron spectrum has been measured by means of multifoil neutron activation spectrometry and a least squares unfolding algorithm; gamma dose was measured using alanine dosimeters. Results show that in a reference position the thermal neutron flux is ( 1.20 ± 0.03 ) × 10 10 cm−2 s−1 when the reactor is working at the maximum power of 250 kW, with the epithermal and fast components, respectively, 2 and 3 orders of magnitude lower than the thermal component. The ratio of the gamma dose with respect to the thermal neutron fluence is 1.2 × 10 - 13 Gy/(n/cm2).

Among the various dosimetric techniques used for characterizing the radiation beams used in radiation therapy, the Electron Paramagnetic Resonance (EPR) arouses increasing interest for applications in various therapy procedures. When a compound is irradiated with ionizing radiations free radicals are produced and their concentration is proportional to the absorbed dose. This allows for dosi-metric measurements through EPR technique which is able to quantitatively de-termine the radical concentration. Our research group has started an investigation of the EPR response of some phenols compounds for possible dosimetric applications. In this work we report the EPR investigation of IRGANOX 1076 pellets and thin films exposed to various type of radiation beams. Phenols are compounds possessing a benzene ring attached to a OH group. After irradiation the final product is a stable phenoxy radical. The stability of such radi-cal can be improved by adding other alkyl chains which can be attached to the benzene ring. In particular, the phenol octadecyl3(3,5ditertbutyl4hydroxyphenyl) propionate (IRGANOX 1076) gave interesting results.

In the last decades several research laboratories have shown an increasing interest aimed at extending the applicability of ESR-dosimetry to radiotherapy with different types of radiation beams. ESR is a spectroscopic method for investigating the structure and dynamics of such paramagnetic species. The concentration of radiation-induced free radicals is proportional to the energy released inside in the medium. Our research group has started an investigation of the ESR response of some phenols compounds for possible ESR dosimetric applications suitable features, such as high efficiency of radiation-matter energy transfer and radical stability at room temperature. In particular, the phenoloctadecyl−3−(3,5−di−tert.butyl−4−hydroxyphenyl)−propionatephenoloctadecyl−3−(3,5−di−tert.butyl−4−hydroxyphenyl)−propionate gave interesting results. In this work we report the ESR investigation of phenols exposed to clinical photon and electron beams.

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 delle radiazioni su fantocci antropomorfi da essi costituiti. Inoltre, la matrice di gel rallenta la diffusione degli ioni ferrosi (Fe2+) e ferrici (Fe3+) in modo che, se il gel viene analizzato entro un paio di ore dall’irraggiamento, gli ioni ferrici rimangono prossimi al loro punto di produzione. Inoltre, il gel favorisce l’ossidazione degli ioni ferrosi durante l'irraggiamento, in modo da aumentare la resa chimica degli ioni ferrici e quindi la sensibilità dei dosimetri. Lo scopo di questo lavoro è l'analisi tramite risonanza magnetica nucleare (NMR) delle proprietà di rilassamento protonico dei gel dosimetrici da noi preparati al variare della concentrazione dei centri paramagnetici (Fe3+) prodotti al variare della dose di irraggiamento. I gel Fricke sono stati irradiati con fasci di fotoni (LINAC) nel range clinico tra 0 e 20 Gy. Le analisi NMR sono state affiancate da acquisizioni di imaging a Risonanza Magnetica Nucleare (MRI) utilizzata in ambito ospedaliero (Galante, 2008). Per valutare la sensibilità a fotoni, abbiamo studiato la dipendenza dei tempi di rilassamento nucleari dalla dose, dalla concentrazione di solfato di ammonio ferroso contenuto all’interno dei gel e dalla presenza di indicatori ottici degli ioni metallici. Inoltre, è stata monitorata la stabilità del segnale per diversi giorni dopo l'irraggiamento. Le acquisizioni MRI sono state finalizzate alla mappatura 3D della dose su fantocci estesi. Vengono presentati e discussi i risultati ottenuti in relazione ad applicazioni dei dosimetri gel Fricke in ambito radioterapico. Questo lavoro evidenzia come valutazioni dosimetriche non possono prescindere dall’ottimizzazione della concentrazione degli additivi.

Among the various dosimetric techniques used for characterizing the radiation beams used in radiation therapy, the electron spin resonance (ESR) arouses increasing interest for applications in various therapy procedures [1]. Free radicals are known to be produced when a compound is irradiated with ionizing radiations. The concentration of radiation-induced free radicals is proportional to the absorbed dos e and this allows for dosimetric measurements through ESR technique which able to quantitatively determine the radical concentration [2]. Our research group has started an investigation of the ESR response of some phenols compounds for possible ESR dosimetric ap plications suitable features, such as high efficiency of radiation-matter energy transfer and radical stability at room temperature [3-5]. In this work we report the ESR investigation of IRGANOX 1076 pellets a nd thin films exposed to various type of radiation beams (clinical photon and electron beams, neutron-photon mixed field).

Intracranial stereotactic radiosurgery (SRS) is a technique to deliver an ablative radiation dose with an extremely sharp dose gradient to small brain tumors. This tecnique allows to deliver high doses of radiation to the tumor sparing the surrounding healthy tissue. In this study the accuracy of the dose delivered in a SRS session by a non conventional radiotherapy machine, the TomoTherapy Hi-Art System, was investigated using an "end-to-end" test. This is perfome d by means of alanine Electron Paramagnetic Resonance (EPR) pe llets. The response of these dosimeters is compared to that of gafchromic films which are particularly suitable for two-dimensional dose verification providing accurate estimate of the distribution and of the gradients of the absorbed dose.

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 imaging investigations of Fricke Xylenol Gel characterized by gelatinous matrix of Agarose for possible applications in clinical photon beams used for radiation therapy. Materials and Methods: NMR relaxometry measurements were performed using an mq-ProFiler single-side relaxometer (Bruker Biospin). MRI imaging was realized on a 1.5 T Achieva scanner (Philips) with an eight channel head coil. The gels were irradiated in the clinical dose range (0– 20 Gy) with a Siemens Primus Low linear accelerator. Results: The main dosimetric features of the NMR signal were investigated. The linearity of the response with dose was observed. In order to assess the photon sensitivity we analyzed the dependence of NMR relaxation time on radiation dose with varying ferrous ammonium sulfate content inside FXG. The ferrous ammonium sulfate content which maximizes sensitivity is 1.75 mM. Furthermore, signal stability was followed for several days after irradiation. Aldo for MRI analysis the dose calibration curves were obtained also with MRI scanner. Moreover, a depth dose profile was reconstructed. Conclusions: We can conclude that FXG dosimeters with optimal ferrous ammonium sulfate content can be regarded as a valuable dosimetric tool to achieve fast information on spatial dose distribution.

Introduction: Among the various dosimetric techniques used for characterizing the radiation beams used in radiation therapy, the electron spin resonance (ESR) arouses increasing interest for applications in various therapy procedures. Free radicals are known to be produced when a compound is irradiated with ionizing radiations. The concentration of radiationinduced free radicals is proportional to the absorbed dose and this allows for dosimetric measurements through ESR technique which enables to quantitatively determine the radical concentration. In this work we report the ESR investigation of phenol pellets and thin films exposed to various types of radiation beams (clinical photon and electron beams, mix field neutrons/photons). Phenols are compounds possessing a benzene ring attached to a OH group. After irradiation the final product is a stable phenoxy radical. Materials and methods: Thanks to their size, the phenolic films here presented are good devices for the dosimetry of beams with high dose gradient and which require accurate knowledge of the precise dose delivered. Photon and electron irradiations at various energies were performed with the Siemens Primus Lowlinear accelerator present at ARNAS Ospedale Civico di Palermo, Italy. Thermal neutron irradiations were performed at the thermal neutron column at the Triga Mark II reactor of LENA (Laboratorio Energia Nucleare Applicata) of Pavia, Italy. ESR dosimeters were readout by means of a Bruker ECS106 spectrometer equipped with a TE102 rectangular cavity at room temperature. Results: The dose response of both pellets and films was found to be linear for all beams used in the dose range analyzed. The signal is very stable in the first days after irradiation. The possibility of obtaining depth dose profile was investigated. Conclusions: In conclusion, the phenols show radiometric features that designate it as a new material for EPR.

This work deals with the dosimetric features of a particular phenolic compound (IRGANOX 1076 ® ) for dosimetry of clinical photon beams by using electron spin resonance (ESR) spectroscopy. After the optimization of the ESR readout parameters (namely modulation amplitude and microwave power) to maximise the signal without excessive spectrum distortions, basic dosimetric properties of laboratory-made phenolic dosimeters in pellet form, such as reproducibility, dose–response, sensitivity, linearity and dose rate dependence were investigated. The dosimeters were tested by measuring the depth dose profile of a 6MV photon beam. A satisfactory intra-batch reproducibility of the ESR signal of the manufactured dosimeters was obtained. The ESR signal proved to increase linearly with increasing dose in the investigated dose range 1–13Gy. The presence of an intrinsic background signal limits the minimum detectable dose to a value of approximately 0.6Gy. Reliable and accurate assessment of the dose was achieved, independently of the dose rate. Such characteristics, together with the fact that IRGANOX 1076 ® is almost tissue-equivalent, and the stability of the ESR signal, make these dosimeters promising materials for ESR dosimetric applications in radiotherapy.

There is a need for a sensitive dosimeter using Electron Spin Resonance spectroscopy for use in medical applications, since non-destructive read-out and dose archival could be achieved with this method. This work reports a systematic ESR investigation of IRGANOX ® 1076 exposed to clinical electron beams produced by a LINAC used for radiation therapy treatments. Recently, dosimetric features of this material were investigated for irradiation with 6 0Co γ -photons and neutrons in both pellet and film shape and have been found promising thanks to their high efficiency of radiation-matter energy transfer and radical stability at room temperature. Here the analysis of the dosimetric features of these ESR dosimeters exposed to clinical electron beams at energies of 7, 10 and 14 MeV, is described in terms of dependence on microwave power and modulation amplitude, response on dose, dependence on beam type, detection limits, and signal stability after irradiation. The analysis of the ESR signal as function of absorbed dose highlights that the response of this material is linear in the dose range investigated (1–13 Gy) and is independent of the beam energy. The minimum detectable dose is found to be smaller than 1 Gy. Comparison of electron stopping power values of these dosimeters with those of water and soft tissue highlights equivalence of the response to electron beams in the energy range considered. The signal intensity was monitored for 40 days after irradiation and for all energies considered and it shows negligible variations in the first 500 h after irradiation whereas after 1100 h the signal decay is only of about 4%. In conclusion, it is found that phenolic compounds possess good dosimetric features which make it useful as a sensitive dosimeter for medical applications.

Purpose Among the various dosimetric techniques used for characterizing the radiation beams used in radiation therapy, the electron spin resonance (ESR) arouses increasing interest for applications in various therapy procedures. In this work we report the ESR investigation of particular phenol compounds exposed to clinical photon and electron beams [1] . Materials and methods Pellets were produced by mixing Phenol (IRGANOX 1076® Sigma Aldrich) and paraffin (10% by weight). The irradiations of dosimeters were performed with photon and electron beams with absorbed doses ranging from 0 to 13 Gy. Basic dosimetric properties of phenolic dosimeters, such as reproducibility, dose-response, sensitivity, linearity and dose rate dependence were investigated. Finally, the dosimeters were tested by measuring the depth dose profile of a 6 MV photon beam. ESR measurements were performed through an X band spectrometer. Readout parameters were optimized to maximize the signal without excessive spectrum distortions. Results A satisfactory intra-batch reproducibility of the ESR signal of the manufactured dosimeters was obtained. The analysis of the ESR signal as function of absorbed dose highlights that the response of this material is linear in the investigated dose range and is independent of the beam energy. Reliable and accurate assessment of the dose was achieved, independently of the dose rate. The minimum detectable dose was evaluated equal to approximately 0.6 Gy as effect to the presence of a no-negligible background signal that deserves further investigations. Conclusion The observed features, along with the tissue-equivalence of IRGANOX 1076® and the stability of the ESR signal, make these dosimeters promising materials for ESR dosimetric applications in radiotherapy.

Purpose In order to provide adequate risk-reducing procedures for MRI personnel (radiographers, anaesthetists, physicists, nurses, technicians, cleaners, etc.), different studies have been developed in the past years. Further to those, in the present work risk assessment concerned with currents induced by non-uniform static magnetic fields in MRI operators performing different tasks in proximity of the scanner has been investigated across a set of different 1.5 T MRI scanners. Methods The first step has been to empirically map the magnetic field around the different scanners and to select a proper adult human body as a heterogeneous volume conductor model. Then, upon observing the way tasks are executed by different categories of MRI personnel, we provided our phantom with the riskiest behaviour and performed simulations in order to possibly predict eddy currents actually induced in a human body. Results Our simulations confirm that the induced fields and currents should not be ignored at ultrahigh B-fields. Indeed, it is possible to observe real procedures that, according to our analysis, could possibly generate E-fields near the level of physiological significance under some circumstances. Conclusions In view of the exposed results, the research here presented, while yielding a new empirical sample to the investigated problem, provides further confirmation to some previous findings. Specifically, it gives further evidence that apart from the requirements of the decree 159 – which our analysis has found always accomplished – there is still room for undesired levels of induced E-fields that a detailed study of movement in ultrahigh static B-fields could reduce below the threshold of physiological significance.

Based on radiobiology evidence, hypofractionated radiotherapy has the potential of improving treatment outcome in prostate cancer patients. In this study, we evaluated the safety, in terms of acutetoxicity, of using moderate hypofractionated radiotherapy delivered with Helical Tomotherapy (HT) to treat prostate cancer patients. Between December 2012 and April 2014, 42 consecutive patients were treated with hypofractionated radiotherapy using HT. All patients received 70 Gy in 28 fractions to PTV1, which included the prostate. In the intermediate risk group, 61.6 Gy were delivered to PTV2, which included the seminal vesicles. In high risk patients, the pelvic nodes were added (PTV3) and received 50.4 Gy. Acute toxicity was recorded prospectively with RTOG and Common Terminology Criteria for Adverse Events 3.0, retrospectively with CTCAE 4.0. Expanded Prostate Cancer Index Composite (EPIC) was measured at baseline and 3 months after end of treatment, to investigate health related quality of life with regards to bladder and gastrointestinal function. Acute toxicity was acceptable, independently from the system used to score side effects. Moderate genitourinary toxicity was more frequent than gastrointestinal toxicity. No correlation between acute side effects and patients’ characteristics or physical dose parameters was registered. EPIC evaluation showed a negligible difference in urinary and bowel function post-treatment, that did not reach statistical significance. Our experience confirms the safety of moderate hypofractionation delivered with HT in prostate cancer patients with low, intermediate and high risk.

Intensity-modulated radiotherapy has been suggested as the technique of choice for locally advanced head and neck cancer patients. In the last decade, most radiotherapy departments have focused their efforts in programs to implement this technique. We report our experience for parotid gland and constrictor muscle sparing with intensity-modulated radiotherapy in head and neck cancer using a step-and-shoot technique. Thirty-four consecutive patients with squamous cell carcinoma of the nasopharynx, oropharynx and larynx treated between June 2008 and June 2011 were retrospectively evaluated. A simultaneous integrated boost was adopted to treat different volumes in 30 fractions over 6 weeks. Priority as organs at risk was given to the parotid glands as well as the constrictor muscle of the pharynx in 53 % (n = 18). Dysphagia and xerostomia were evaluated according to RTOG/EORTC scale at 6, 12 and 24 months. Outcomes were analysed using Kaplan–Meier curves. The median follow-up was 43 months. The 5-year overall survival was 70 %, and local control was 94 %. Grade 2 dysphagia and xerostomia at 6, 12 and 24 months were as follows: 26 % (n = 9), 23 % (n = 8), 23 % (n = 8) and 21 % (n = 7), 12 % (n = 4), 12 % (n = 4), respectively. No grade 3 or 4 toxicity was found. Ordinal logistic regression analysis demonstrated that hyposalivation was the main predictive factor for late dysphagia. Excellent loco-regional results were achieved with acceptable acute and late toxicities. The low rate of late dysphagia was related to parotid gland sparing; we did not observe a correlation between late dysphagia and dose to pharyngeal constrictors.

The effectiveness of Ag+-based antimicrobial film in inhibiting the growth of an Alicyclobacillus acidoterrestris strain was assessed. The proposed active film was obtained by depositing via plasma an Ag-containing polyethylenoxide-like coating on a polyethylene layer. Tests were conducted at 44 °C, monitoring the viable cell concentration of the investigated microorganism into 2 different media: acidified malt extract broth and apple juice. Results indicate that the investigated active film successfully inhibited the growth of A. acidoterrestris in both media. Results also indicate that the effectiveness of the film depends on the type of medium tested.

It is known that polymethacrylic acid functions as a protective colloid for the emulsion polymerization of vinyl acetate. The resultant latex shows excellent mechanical freeze-thaw stability. The locus of the polymethacrylic acid has been determined by ion-exchange and conductometric titration, serum replacement using Millipore and Nucleopore filters, and exhaustive extraction of the dried films with hot water. The results show that 75–85% of the polymethacrylic acid is strongly adsorbed on the poly(vinyl acetate) latex particles and the remainder is solute polymer in the aqueous phase. The excellent stability of this latex is attributed speculatively to both steric and electrostatic repulsion arising from the adsorbed polymethacrylic acid.

Polymethacrylic acid functions as a protective colloid in the emulsion polymerization of vinyl acetate, particularly in combination with anionic-nonionic surfactants. The combination of polymethacrylic acid and a nonylphenolethoxylate ester of phosphoric acid gives high-solids latex which shows excellent stability to mechanical shear and reezing-and-thawing. The locus of the polymethacrylic acid in this system was determined by ion exchange followed by conductometric titration, serum replacement using both Millipore and Nuclepore filters followed by conductometric titration, and exhaustive extraction of the dried films with hot water followed by analysis of the fractions by infrared spectroscopy and thermogravimetric analysis. These results show that 70-80% of the polymethacrylic acid is strongly adsorbed on the polyvinyl acetate latex particle surfaces and the remainder is solute polymer in the aqueous phase; little, if any, is grafted to the particle surface. The excellent stability of this latex is attributed speculatively to both steric and electrostatic repulsion arising from the adsorbed polymethacrylic acid.

The Authors after a theoric introduction in regard to the taxonomic position, the history and the epidemiology of the Salmonella wien, explain the biologic characteristic of the bacterium according to results of their experiments.

In the aircraft industry, the use of fiber reinforced materials for primary structural components over metallic parts has increased up to more than 50% in the recent years, because of their high strength and high modulus to weight ratios, high fatigue and corrosion resistance. Currently, the need of lowering weight and fuel consumption is pushing the world’s largest aircraft manufacturers in the design and building of structures entirely made of composites. Fuselage structure plays an important role in absorbing the kinetic energy during a crash. Through the deformation, crushing and damage of fuselage sub-floor structure, a survivable space inside the cabin area should be preserved during and after a crash impact in order to minimize the risk of passengers’ injuries. In this work, a Finite Element (FE) model of a full-scale 95% composites made fuselage section of a regional aircraft under vertical drop test is presented. The experiment, conducted by the Italian Aerospace Research Centre (CIRA) with an actual impact velocity of 9.14 m/s in according to the FAR/CS 25, has been numerically simulated. Two ATDs (Anthropomorphic Test Dummies), both 50th percentile, seats and belts have been modelled to reproduce the experimental setup. The results of the simulation, performed by using LS-DYNA® explicit FE code, have been validated by correlation with the experimental ones. Such comparisons highlight that a good agreement has been achieved. The presented FE model allows verifying the structural behavior under a dynamic load condition and also estimating the passive safety capabilities of the designed structure. Since the experiment is expensive and non-repeatable, a FE model can be used for Certification by Analysis purposes since, if established, it is able to virtually demonstrate the compliance to the airworthiness rules.

In the last decades several research laboratories have shown an increasing interest aimed at extending the applicability of Electron Spin Resonance (ESR) dosimetry to radiotherapy with different types of radiation beams. ESR is a spectroscopic method for investigating the structure and dynamics of such paramagnetic species. Free radicals are known to be produced when a compound is irradiated with ionizing radiations. The concentration of radiation-induced free radicals is proportional to the energy released inside in the medium and this allows for dosimetric measurements through ESR technique which able to quantitatively determine the radical concentration. The use of alanine as a dosimetric material gave the possibility to apply ESR spectroscopy for high-dose standardization and dose control in radiation processing. The ESR dosimetric method has many advantages such as simple and rapid dose evaluation, the readout procedure is non-destructive, linear response of many organic and inorganic compounds. ESR detectors show a behavior that suggest possible applications for various kinds of beams used for radiation therapy. Nowadays, the most widely used organic compound as a dosimeter is the alanine. However, many researches are in progress with the aim at improving sensitivity of ESR dosimetry for doses much smaller than 1 Gy. More sensitive materials than alanine are needed to make the ESR dosimeter competitive with other dosimetry systems. Our research group has started an investigation of the ESR response of some phenols compounds for possible ESR dosimetric applications suitable features, such as high efficiency of radiation-matter energy transfer and radical stability at room temperature. Phenols are compounds possessing a benzene ring attached to a OH group. After irradiation the final product is a stable phenoxy radical. The stability of such radical can be improved by adding other alkyl chains which can be attached to the benzene ring. In particular, the phenol octadecyl-3-(3,5-di-tert.butyl-4-hydroxyphenyl)-propionate gave interesting results. Moreover, its high molecular weight, the low volatility and the compatibility with the dosimeter binding material (wax) are advantages with respect to lower molecular weight phenols. In this work we report the ESR investigation of phenols exposed to clinical photon and electron beams. The dosimetric features of these ESR dosimeters (dependence on microwave power and modulation amplitude, their response after gamma and electron irradiations, dependence on beam type and energy, the detection limits for both beam typologies, signal stability after irradiation) were investigated and the results are reported.

In the last decades several research laboratories have shown an increasing interest aimed at extending the applicability of Electron Paramagnetic Resonance (EPR) dosimetry to radiotherapy with different types of radiation beams. EPR is a spectroscopic method for investigating the structure and dynamics of such paramagnetic species. Free radicals are known to be produced when a compound is irradiated with ionizing radiations. The concentration of radiation-induced free radicals is proportional to the energy released inside in the medium and this allows for dosimetric measurements through EPR technique. The use of alanine as a dosimetric material gave the possibility to apply EPR spectroscopy for high-dose standardization and dose control in radiation processing (Marrale 2016). The EPR dosimetric method has many advantages such as simple and rapid dose evaluation, the readout procedure is non-destructive, linear response of many organic and inorganic compounds. EPR detectors show a behavior that suggest possible applications for various kinds of beams used for radiation therapy. Nowadays, the most widely used organic compound as a dosimeter is the alanine. However, many researches are in progress with the aim at improving sensitivity of EPR dosimetry for doses much smaller than 1 Gy. More sensitive materials than alanine are needed to make the EPR dosimeter competitive with other dosimetry systems. Our research group has started an investigation of the EPR response of some phenols compounds for possible EPR dosimetric applications suitable features, such as high efficiency of radiation-matter energy transfer and radical stability at room temperature. Phenols are compounds possessing a benzene ring attached to a OH group. After irradiation the final product is a stable phenoxy radical. The stability of such radical can be improved by adding other alkyl chains which can be attached to the benzene ring. The phenol octadecyl-3-(3,5-di-tert.butyl-4-hydroxyphenyl)-propionate gave interesting results. Moreover, its high molecular weight, the low volatility and the compatibility with the dosimeter binding material (wax) are advantages with respect to lower molecular weight phenols. In this work we report the EPR investigation of phenols exposed to clinical photon and electron beams (Gallo, 2016). The dosimetric features of these EPR dosimeters (dependence on microwave power and modulation amplitude, their response after gamma and electron irradiations, dependence on beam type and energy, the detection limits for both beam typologies, signal stability after irradiation) were investigated and the results are reported.

Indici morfologici e parametri strutturali nello sviluppo di modelli per materiali a struttura complessa