Metrofission project: An overview of the ENEA contribution

Abstract The paper describes the progress made by ENEA-INMRI in the research carried out within the framework of the Joint Research Project (JRP) ENG08 Metrofission of the European Metrology Research Programme (EMRP). This JRP aims to solve important problems related to the development of the Generation IV (GenIV) nuclear power plants in Europe as required by new demands of energy supplies that must be secure, sustainable, of high quality and also able to reduce the green house gas emissions. In the Metrofission project the ENEA-INMRI is directly involved in three Working Packages (WPs): the WP6, that aims to develop a portable Triple-to-Double-Coincidence-Ratio (TDCR) system for measuring in-situ of pure beta radionuclides; the WP7, devoted to the development of modern acquisition techniques based on Digital Coincidence Counting (DCC) with high sampling speed for radionuclide standardization; the WP8, leaded by ENEA-INMRI, which takes into account the impact of the project toward the end-users and the nuclear industry. The new prototype of the ENEA-INMRI portable TDCR counter will be presented. The preliminary results obtained in the activity measurements of 14C and 63Ni standard sources carried out by the new counter equipped with the new front-end electronics based on the CAEN Digitizer DT5720 will be discussed

COVID-19 in solid organ transplantation: an analysis of the impact on transplant activity and wait lists

The limited knowledge about COVID-19, the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), makes mortality figures hard to interpret in the undetermined prevalence of an asymptomatic infection. Treatments are currently being tested, but without proof of an effective vaccination, the fear of further detrimental outcomes, as a result of a second wave, persists. One of the main differences in the death toll among the various countries seems related to the different response to the outbreak: early measures of containment as lockdown, revealed their effectiveness in mitigating the virus spread, with the earliest the lockdown, the lower the death toll

Phantom validation of quantitative Y-90 PET/CT based dosimetry in liver radioembolisation

Background PET/CT has recently been shown to be a viable alternative to traditional post-infusion imaging methods providing good quality images of 90Y-laden microspheres after selective internal radiation therapy (SIRT). In the present paper, first we assessed the quantitative accuracy of 90Y-PET using an anthropomorphic phantom provided with lungs, liver, spine, and a cylindrical homemade lesion located into the hepatic compartment. Then, we explored the accuracy of different computational approaches on dose calculation, including (I) direct Monte Carlo radiation transport using Raydose, (II) Kernel convolution using Philips Stratos, (III) local deposition algorithm, (IV) Monte Carlo technique (MCNP) considering a uniform activity distribution, and (V) MIRD (Medical Internal Radiation Dose) analytical approach. Finally, calculated absorbed doses were compared with those obtained performing measurements with LiF:Mg,Cu,P TLD chips in a liquid environment. Results Our results indicate that despite 90Y-PET being likely to provide high-resolution images, the 90Y low branch ratio, along with other image-degrading factors, may produce non-uniform activity maps, even in the presence of uniform activity. A systematic underestimation of the recovered activity, both for the tumor insert and for the liver background, was found. This is particularly true if no partial volume correction is applied through recovery coefficients. All dose algorithms performed well, the worst case scenario providing an agreement between absorbed dose evaluations within 20%. Average absorbed doses determined with the local deposition method are in excellent agreement with those obtained using the MIRD and the kernel-convolution dose calculation approach. Finally, absorbed dose assessed with MC codes are in good agreement with those obtained using TLD in liquid solution, thus confirming the soundness of both calculation approaches. This is especially true for Raydose, which provided an absorbed dose value within 3% of the measured dose, well within the stated uncertainties. Conclusions Patient-specific dosimetry is possible even in a scenario with low true coincidences and high random fraction, as in 90Y–PET imaging, granted that accurate absolute PET calibration is performed and acquisition times are sufficiently long. Despite Monte Carlo calculations seeming to outperform all dose estimation algorithms, our data provide a strong argument for encouraging the use of the local deposition algorithm for routine 90Y dosimetry based on PET/CT imaging, due to its simplicity of implementation

14 MeV neutrons for 99Mo/99mTc production: Experiments, simulations and perspectives

Background: the gamma-emitting radionuclide Technetium-99m (99mTc) is still the workhorse of Single Photon Emission Computed Tomography (SPECT) as it is used worldwide for the diagnosis of a variety of phatological conditions.99mTc is obtained from99Mo/99mTc generators as pertechnetate ion, which is the ubiquitous starting material for the preparation of99mTc radiopharmaceuticals.99Mo in such generators is currently produced in nuclear fission reactors as a by-product of235U fission. Here we investigated an alternative route for the production of99Mo by irradiating a natural metallic molybdenum powder using a 14-MeV accelerator-driven neutron source. Methods: after irradiation, an efficient isolation and purification of the final99mTc-pertechnetate was carried out by means of solvent extraction. Monte Carlo simulations allowed reliable predictions of99Mo production rates for a newly designed 14-MeV neutron source (New Sorgentina Fusion Source). Results: in traceable metrological conditions, a level of radionuclidic purity consistent with accepted pharmaceutical quality standards, was achieved. Conclusions: we showed that this source, featuring a nominal neutron emission rate of about 1015s−1, may potentially supply an appreciable fraction of the current99Mo global demand. This study highlights that a robust and viable solution, alternative to nuclear fission reactors, can be accomplished to secure the long-term supply of99Mo

Preliminary Assessment of Radiolysis for the Cooling Water System in the Rotating Target of {SORGENTINA}-{RF}

The SORGENTINA-RF project aims at developing a 14 MeV fusion neutron source featuring an emission rate in the order of 5-7 x 10(13) s(-1). The plant relies on a metallic water-cooled rotating target and a deuterium (50%) and tritium (50%) ion beam. Beyond the main focus of medical radioisotope production, the source may represent a multi-purpose neutron facility by implementing a series of neutron-based techniques. Among the different engineering and technological issues to be addressed, the production of incondensable gases and corrosion product into the rotating target deserves a dedicated investigation. In this study, a preliminary analysis is carried out, considering the general layout of the target and the present choice of the target material

14 MeV Neutrons for 99Mo/99mTc Production: Experiments, Simulations and Perspectives

Background: the gamma-emitting radionuclide Technetium-99m (99mTc) is still the workhorse of Single Photon Emission Computed Tomography (SPECT) as it is used worldwide for the diagnosis of a variety of phatological conditions. 99mTc is obtained from 99Mo/99mTc generators as pertechnetate ion, which is the ubiquitous starting material for the preparation of 99mTc radiopharmaceuticals. 99Mo in such generators is currently produced in nuclear fission reactors as a by-product of 235U fission. Here we investigated an alternative route for the production of 99Mo by irradiating a natural metallic molybdenum powder using a 14-MeV accelerator-driven neutron source. Methods: after irradiation, an efficient isolation and purification of the final 99mTc-pertechnetate was carried out by means of solvent extraction. Monte Carlo simulations allowed reliable predictions of 99Mo production rates for a newly designed 14-MeV neutron source (New Sorgentina Fusion Source). Results: in traceable metrological conditions, a level of radionuclidic purity consistent with accepted pharmaceutical quality standards, was achieved. Conclusions: we showed that this source, featuring a nominal neutron emission rate of about 1015 s−1, may potentially supply an appreciable fraction of the current 99Mo global demand. This study highlights that a robust and viable solution, alternative to nuclear fission reactors, can be accomplished to secure the long-term supply of 99Mo

Kidney transplantation and the lockdown effect

The coronavirus disease 2019 (COVID-19) disrupted the healthcare system: when ‘business as usual’ is no longer possible, as intensive care units (ICUs) follow the principle of ‘capacity to benefit’ to accommodate as many COVID-19 patients requiring ventilation as possible, there is an important decrease in the organ pool [1]. The lack of ICU capacity to accommodate donors dying from different reasons than COVID-19 leads to a drastic reduction of the transplant activity, important resource to be preserved in a safe and clean environment, separated by the rest of the dedicated COVID-19 beds. There is evidence, in fact, that COVID-19 could be a nosocomial infection [2]. Furthermore, transplantation requires immunosuppression. In population at risk, the innate immune system fails to produce an adequate adaptive response, so persistent self-induced inflammation can cause mortality and mounting an early adaptive immune response may save lives [3], a concept that fails to match with the required post-transplant immunosuppression

Feasibility study on the application of solid state tracks detectors for fast surveys of residual alpha contamination in decommissioning activities

A feasibility study concerning the application of Poly-Allyl-Diglycol Carbonate (CR-39TM) solid state tracks detectors for fast survey of residual alpha contamination has been carried out at Casaccia Research Center, as a joint effort from ENEA, Sogin, and Sapienza University of Rome. The main target of the ac- tivity is to develop and set up a fast and economic method for assessing the presence of residual ura- nium, plutonium, and/or mixed oxides (MOX) traces on walls, floor, furniture, and small objects (PC- displays, keyboards, tools, etc.) of hot laboratories under decommissioning. The key idea is using CR-39TM foils for cladding surfaces under investigation for recognizing the typical uranium and plutonium clusters originated by alpha particles interaction with CR-39TM, that are clearly distinguished from the tracks originated by radon decay products. Results of experimental tests have given a clear picture of alpha tracks clusters originated by plutonium sources, while radon decay products gave uniform alpha tracks' distribution