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This paper presents the results of the irradiation, performed with atmospheric-like neutrons and heavy-ions, of Commercial Off-the Shelf Components (COTS), which can be used in space missions. In such cases, it is crucial to perform tests in a radiation environment that emulates the environment of different orbits around Earth. In our study we used atmosphericlike neutrons with fluences up to 1011 neutrons/cm-2 and Kr ions of fluences up to 107 ions/cm-2. These intensities are augmented with respect to the atmospheric one in order to shorten the irradiation time while simulating a long-time exposure during a possible mission in Low Earth Orbit (LEO). A similar radiation environment to LEO can also be present during High-Energy Physics experiments. Therefore, the study herby reported can also be helpful for accelerator physics. In this paper we show in detail procedures, setup and results we have obtained on a commercial device normally exploited in automotive environments., Comment: 9 pages, 10 figures, 7 tables

[EN] We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from C-11-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that C-11-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naive, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia. (c) 2018 Elsevier Masson SAS. All rights reserved.

We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from 11C-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that 11C-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naïve, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia.

Magnetic Resonance (MR) guided Focused Ultrasound Surgery (MRgFUS) technology, combined with High Intensity Focused Ultrasound (HIFU) beams, has opened to new therapeutic protocols for various pathological conditions. The success of this therapy relies on the accuracy of the guidance for therapy provided by thermal mapping of sonication, which is obtained with MR imaging. In addition, in recent years, multimodality Positron Emission Tomography and Magnetic Resonance Imaging (PET/MRI) imaging has been developed. This technique is able to provide simultaneous functional and soft tissue morphological imaging and, for this reason, it is particularly engaging for brain imaging. The key concept behind this work is to assess the feasibility of a brain-dedicated PET-and MRI-guided FUS device providing real-time evaluation of the outcome of the HIFU therapy. At first, a method to improve imaging capabilities of small-ring PET scanners will be presented. It will be showed that thanks to this method it is possible to obtain high tomographic spatial resolution with an affordable, brain-dedicated, PET scanner based on monolithic scintillation crystals and able to work as an insert in a MRI system. Moreover, simulations of an anthropomorphic phantom will be made in order to evaluate the effect of different HIFU protocols and, in addition, to investigate the capability of thermal maps provided by MRI for assessing the effect of the HIFU treatment. Finally, from the comparison of the spatial resolutions provided by each imaging technique (PET, MRI and thermal MRI) and the HIFU therapy, it will be possible to assess the feasibility of the proposed multimodality device. The system suggested in this work should be composed of a MRI scanner with a PET insert and a customized MRI-compatible focused ultrasound applicator. It could be very useful for the diagnosis and therapy of brain tumors thanks to the possibility of a real-time evaluation of the effect of the HIFU treatment. The proto, QC 20190213

In recent years, a new generation of compact gamma cameras, based on monolithic scintillation crystals, has become increasingly widespread. The main advantages of small FoV gamma cameras with respect to the standard ones are high portability, low cost and low weight, allowing several clinical applications, from scintimammography to intraoperative tumor localization. In gamma cameras based on continuous scintillation crystals, intrinsic Spatial Resolution (SR) is mainly affected by two factors: scintillation light collection efficiency and overall crystal thickness. The first affects the counting statistics, the latter impacts on the light distribution width. To fully investigate the potentiality of these devices we took advantage of Monte Carlo simulations as a valuable tool to physically characterize the imaging systems and to establish a priori reference values. GEANT4 toolkit allows to completely describe the phenomenon of light emission and propagation through the media, providing control to all second-order factors existing in real systems. Results show clearly that SR is dependent on the number of photoelectrons produced and on the light spread. Furthermore, the role of refractive index has been unambiguously identified as an important factor affecting light collection and consequently SR., QC 20190219