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Background/Objectives: Chagas disease is a neglected tropical disease caused by infection with the parasite Trypanosoma cruzi. Benznidazole and nifurtimox are the only approved drugs for treating this condition, but their low aqueous solubility may lead to erratic bioavailability. This work aimed for the first time to formulate tablets of nifurtimox by hot melt extrusion coupled with 3D printing as a strategy to increase drug dissolution and the production of tablets with dosage on demand. Methods: Different pharmaceutical-grade polymers were evaluated through film casting, and those with promising nifurtimox amorphization capacity were further used to prepare filaments by hot melt extrusion. The printability of the obtained filaments was tested, and the polyvinyl alcohol filament was further used for printing tablets containing 120 and 60 mg of nifurtimox. Results: Three-dimensional tablets showed a remarkable improvement in the drug dissolution rate compared to commercial tablets and a dissolution efficiency 2.8 times higher. In vivo studies were carried out on Swiss mice. Parasitemia curves of nifurtimox printed tablets were significantly superior to the pure drug. Moreover, NFX 3D tablets provided a similar Trypanosoma cruzi reduction in plasmatic concentration to benznidazole, the gold-standard drug for acute-phase treatment of the Chagas disease. Conclusions: The findings of this work showed that hot melt extrusion coupled with 3D printing is a promising alternative for increasing nifurtimox biopharmaceutical properties and an attractive approach for personalized medicine.

Mapping the soil moisture is a key activity in water management and sustainable agriculture, especially in regions characterised by fragile agri-food systems and water scarcity. Cosmic Ray Neutron Sensors (CRNS) is a contactless nuclear technology used for estimating soil moisture (SM) content on a 20–30 m scale at the landscape level. Very interestingly, this corresponds to the so-called intermediate scale gap between the local probes, operating on the meter scale, and the satellite-based technologies, working on the kilometre scale and above. In state-of-art CRNS, the cosmic neutrons degraded by the soil are simply counted by a slightly moderated thermal neutron counter. After a calibration procedure, the SM is inferred by combining this count rate with environmental parameters: the atmospheric pressure, temperature and the air humidity. As the SM affects not only the environmental neutron fluence rate but also its energy distribution, this study was organised in such a way to understand if a CRNS with spectrometric capabilities could provide improved information on the SM distribution. To this aim, an environmental neutron spectrometer was designed by extending the Bonner Spheres to a more sensitive system made of moderating cylinders embedding long BF 3 proportional counters, the Moderating Cylinders Spectrometer (MCS). Relying on literature environmental neutron spectra, corresponding to different SM values in a standardised soil, the count rates in the MCS were calculated for different values of SM. To simulate various counting scenarios, these count rates were associated to different levels of “realistic” uncertainties and unfolded by means of the FRUIT code. The resulting neutron spectra are compared to the literature ones, allowing at estimating the resolving power of the spectrometer in terms of SM.

Boron is an elective element for the Prompt Gamma Activation Analysis (PGAA), due to its exceptionally large neutron capture cross section. This technique, usually performed in nuclear reactors with neutron fluxes as high as 10 8  cm −2  s −1 , can determine quantities of boron as low as tens of nanograms. Some applications, such as the industry of neutron shielding materials, would better benefit from a less sensitive but more portable and accessible boron PGAA, which could be established at construction or fabrication sites. For these purposes ENEA and INFN jointly setup a compact PGAA based on a 0.5 cm 3 Cadmium–Zinc–Telluride gamma spectrometer and the HOTNES thermal neutron source. Relying on a series of borated resins with known composition and on comprehensive experimental and Monte Carlo evaluations, this technique features a detection limit in the order of few milligrams in terms of boron mass. As the facility consists simply on a lab-scale neutron source and a polyethylene block with well-established geometry, this simplified PGAA system is suited to be replicated or transported to construction or fabrication sites for QA/QC purposes on borated construction materials for the nuclear sector.

The prompt gamma activation analysis (PGAA) is an elemental analysis based on the γ -ray emission following neutron radiative capture by nuclides. A simplified and compact PGAA for the determination of boron in borated concrete was setup at the HOTNES neutron facility, relying on common laboratory equipment. The thermal neutron field has fluence rate of about 20 cm −2  s −1 and is obtained from a moderated americium-boron neutron source. The γ -ray detector is a common 3″ × 3″ NaI(Tl) scintillator. Samples of borated resin with the same geometry of the concrete samples were manufactured and used as standards. A specific “blank sample” correction was developed to isolate the boron contribution in the spectra obtained by irradiating the concrete samples. Boron quantities in the order of 1.5–2.0 g were measured in the concrete samples with uncertainty in the order of ± 6%, in agreement with manufacturer's expectations. The Detection Limit of this simplified and compact boron analysis is in the order of 0.3 g in terms of boron mass, in line with values given in literature for PGAA-based boron analysis performed at research fission reactors.

241 Americium-boron (α,n) neutron sources have been produced for various application from nuclear industry to well logging or radiation protection. Compared to 241 Americium–beryllium sources their specific emission rate is lower, but their spectrum is narrower, and their production cycle uses boron, which is less toxic than beryllium. Very few data are available in literature about the energy distribution of this neutron source: the 2001 version of Standard ISO 8529-1 reported a reference spectrum derived from 1970s data, exhibiting a single peak from about 1 to 6 MeV. Other spectra are available in recent works from PTB and NPL, based on high-resolution spectrometers and Bonner spheres. ENEA Frascati owns a 241 Am-B neutron source with nominal emission rate 3.5 × 10 6  s −1 . Knowing its spectrum is important, as this source is used to feed the HOTNES (Homogeneous Thermal Neutron Source) facility. A spectrometry experiment was organized relying on the recently developed NCT-WES neutron spectrometer. Belonging to the family of the Single Moderator Neutron Spectrometers, NCT-WES is a convenient alternative to Bonner spheres as it derives the whole spectrum from a single exposure. The experimental data were elaborated in comparison with the existing literature spectra. As a main results of the study, the spectrum of the ENEA 241 Am-B neutron source nearly perfectly agrees with that derived at NPL.

Electronic personal dosemeters (EPD) are powerful tools for achieving ALARA (As Low As Reasonably Achievable) objectives in operational radiation protection. EPD for photons are well developed and their performances usually comply with relevant Standards. By contrast, a very few commercial models exist for neutrons and their energy dependence is too large for using them without pre-information on the workplace neutron spectrum. Within the INFN-based DOIN (DOsimetro Indossabile per Neutroni) project, a new EPD for neutrons was prototyped. Owing to a new patented design, a good dose response was achieved in the energy interval from thermal neutrons up to the quality of 241 Am-Be. The response is nearly isotropic and, if compared to commercial models, exhibits higher sensitivity.

A Bonner sphere spectrometer was designed for the measurement of cosmic neutrons at high elevation within the INFN-based project SAMADHA. The spectrometer consists of 8 moderating spheres (6 polyethylene and 2 polyethylene plus high atomic number inserts), each embedding a cylindrical 3 He proportional counter. The response matrix was calculated with MCNP6. In view of the very low counting rates expected in the environment, specific design criteria were adopted to prevent non-neutron signals. The spectrometer was exposed in a reference 241 Am–Be neutron field at Politecnico di Milano , which allowed the estimation of the overall uncertainty of the simulated response matrix of about ± 2%.

Characterising neutron sources for calibration or generic testing purposes is a complex task, as the neutron spectrum may depend, to some extent, on the construction characteristics of the source. Bonner spheres (BS) are the traditional spectrometric transfer instruments, but they are very sensitive to room scatter and required measurements are highly time consuming. The recently developed NCT-WES device, belonging to the family of the Single Moderator Neutron Spectrometers, has been proposed as a convenient alternative to BS. This work presents the results of a demonstration campaign organised at the STUK neutron metrology laboratory (Finland) in July 2023, where the spectra from two 252 Cf and two 241 Am-Be sources were determined. For the 241 Am-Be sources, the results were compared to the spectra of two categories recently introduced by ISO 8529-1. Based on the results it was concluded that the “large” source category is an appropriate selection for STUK sources. The campaign also proved the operational advantages of NCT-WES as spectrometric transfer instrument.

FLASH radiotherapy (FRT) is a novel radiotherapy technique based on dose rates that are several orders of magnitude greater than those used in conventional radiotherapy (40 Gy/s vs. 0.5–5 Gy/min). FRT is still in its preclinical and early clinical stage of development. However these studies indicate that FRT is more effective in sparing normal tissues from radiation-related side effects, as compared to conventional radiotherapy. This is the so-called \"FLASH effect\" and was observed with multi-MeV electron beams. Before FRT is made available to humans, more basic research is needed to fully understand its radiobiology fundamentals. Meanwhile, suitable radiation sources and dosimetric tools are gradually becoming available. Within this framework, INFN-LNF developed the Unbalanced Core Detector (UCD), a novel type of electron dosimeter designed to operate in the FRT domain. UCD main characteristics are the nearly isotropic response, the independence from the electron energy, the very high radiation resistance, the linearity up to dose rates of MGy/s and the possibility to record the time evolution of a single radiation pulse. UCD was tested using 7 and 9 MeV electron beams produced with the ElectronFlash accelerator from Sordina IORT Technologies (SIT S.p.A.) in Aprilia, Italy. UCD was used to measure dose distributions in a water phantom. The results well compare to those obtained with a flashDiamond detector from PTW.

Within the framework of the ENTER_BNCT INFN project, commercially available silicon carbide sensors with 1 mm 2 area were made sensitive to thermal neutrons. Two different thermal neutron radiators were exploited, leading to different measurement sensitivities and degrees of radiation resistance: (1) a 6 LiF coating on the sensor or (2) the air volume between the sensor surface and the walls of the package. Thermal neutron sensitivity and radiation resistance were assessed in the well-controlled thermal neutron beam produced in the thermal column of the TRIGA reactor at LENA Pavia. The sensors were connected to a nuclear spectroscopy system and irradiated up to an accumulated fluence of 5.6 × 10 13 cm - 2 distributed in nine steps, ranging from 10 12 cm - 2 to 10 13 cm - 2 each, with the reactor operating at the maximum power of 250 kW. After each “damaging step”, the reactor power was lowered to 100 W, and the pulse height distribution of the detectors was recorded. This allowed to observe the effects of the progressive damage by inspecting the pulse height distribution. These effects were evident in the 6 LiF-coated detector and fairly observable in the air-type one. To interpret the spectra, a specific Monte Carlo code was written to model the neutron interaction in both detectors, achieving very satisfactory agreement with the experiment.