Improving Americium/Curium Separation Factors in the AmSel Process through Symmetry Lowering of the Diglycolamide Extractant.

Partitioning and transmutation are important strategies for closing the nuclear fuel cycle. The diglycolamide extractant TODGA has played a major role in the development of solvent extraction processes for nuclear fuel reprocessing due to its good extraction performance, its hydrolytic and radiolytic stability, and its compliance with the CHON principle. However, due to drawbacks such as the tendency to form a third phase during extraction if no phase modifiers are used, continued research on diglycolamide-type extractants has led to the development of diglycolamides with decreased symmetry.

How much do Ga-, Lu- and I-based radiopharmaceuticals contribute to the global radiation exposure of nuclear medicine staff?

Background: The radiation exposure of nuclear medicine personnel, especially concerning extremity doses, has been a significant focus over the past two decades. This study addresses the evolving practice of NM, particularly with the rise of radionuclide therapy and theranostic procedures, which involve a variety of radionuclides such as Ga, Lu, and I. Traditional studies have concentrated on common radioisotopes like Tc, F, and Y, but there is limited data on these radionuclides, which are more and more frequently used.

Development and implementation of a simulated microgravity setup for edible cyanobacteria.

Regenerative life support systems for space crews recycle waste into water, food, and oxygen using different organisms. The European Space Agency's MELiSSA program uses the cyanobacterium Limnospira indica PCC8005 for air revitalization and food production. Before space use, components' compatibility with reduced gravity was tested.

Assessment of fluence- and dose-averaged linear energy transfer with passive luminescence detectors in clinical proton beams.

This work investigates the use of passive luminescence detectors to determine different types of averaged linear energy transfer (LET-) for the energies relevant to proton therapy. The experimental results are compared to reference values obtained from Monte Carlo simulations.Optically stimulated luminescence detectors (OSLDs), fluorescent nuclear track detectors (FNTDs), and two different groups of thermoluminescence detectors (TLDs) were irradiated at four different radiation qualities.

Towards a European prospective data registry for particle therapy.

The evidence for the value of particle therapy (PT) is still sparse. While randomized trials remain a cornerstone for robust comparisons with photon-based radiotherapy, data registries collecting real-world data can play a crucial role in building evidence for new developments. This Perspective describes how the European Particle Therapy Network (EPTN) is actively working on establishing a prospective data registry encompassing all patients undergoing PT in European centers.

Joint EURADOS-EANM initiative for an advanced computational framework for the assessment of external dose rates from nuclear medicine patients.

Background: In order to ensure adequate radiation protection of critical groups such as staff, caregivers and the general public coming into proximity of nuclear medicine (NM) patients, it is necessary to consider the impact of the radiation emitted by the patients during their stay at the hospital or after leaving the hospital. Current risk assessments are based on ambient dose rate measurements in a single position at a specified distance from the patient and carried out at several time points after administration of the radiopharmaceutical to estimate the whole-body retention. The limitations of such an approach are addressed in this study by developing and validating a more advanced computational dosimetry approach using Monte Carlo (MC) simulations in combination with flexible and realistic computational phantoms and time activity distribution curves from reference biokinetic models.

New optically stimulated luminescence dosimetry film optimized for energy dependence guided by Monte Carlo simulations.

Optically stimulated luminescence (OSL) film dosimeters, based on BaFBr:Euphosphor material, have major dosimetric advantages such as dose linearity, high spatial resolution, film re-usability, and immediate film readout. However, they exhibit an energy-dependent over-response at low photon energies because they are not made of tissue-equivalent materials. In this work, the OSL energy-dependent response was optimized by lowering the phosphor grain size and seeking an optimal choice of phosphor concentration and film thickness to achieve sufficient signal sensitivity.

Effectiveness of [Cu]Cu-trastuzumab as a theranostic against HER2-positive breast cancer.

Purpose: To evaluate the imaging and therapeutic properties (theranostic) of Cu-labeled anti-human epidermal growth factor receptor II (HER2) monoclonal antibody trastuzumab against HER2-positive breast cancer (BC).

Methods: We conjugated trastuzumab with p-SCN-Bn-NOTA, 3p-C-NETA-NCS, or p-SCN-Bn-DOTA, and radiolabeled with [Cu]CuCl. Immunoconjugate internalization was evaluated in BT-474, JIMT-1 and MCF-7 BC cells.

Separation of americium from highly active raffinates by an innovative variant of the AmSel process based on the ionic liquid Aliquat-336 nitrate.

A new variant of the AmSel (Americium Selective Separation) system for the separation of Am(iii) from a PUREX raffinate was tested in which the aliphatic diluent was replaced by the ionic liquid Aliquat-336 nitrate. For this ionic liquid variant, the kinetics, and the influence of both the HNO concentration and the ligand concentration on the stripping were evaluated. In addition, both the original AmSel system, and the ionic liquid variant were demonstrated on a simulated highly active raffinate.

Complete patient exposure during paediatric brain cancer treatment for photon and proton therapy techniques including imaging procedures.

Background: In radiotherapy, especially when treating children, minimising exposure of healthy tissue can prevent the development of adverse outcomes, including second cancers. In this study we propose a validated Monte Carlo framework to evaluate the complete patient exposure during paediatric brain cancer treatment.

Materials And Methods: Organ doses were calculated for treatment of a diffuse midline glioma (50.

The waterbodies of the halo-volcanic Dallol complex: earth analogs to guide us, where to look for life in the universe.

Microbes are the Earth life forms that have the highest degree of adaptability to survive, live, or even proliferate in very hostile environments. It is even stated that microbes can cope with any extreme physico-chemical condition and are, therefore, omnipresent all over the Earth: on all the continents, inside its crust and in all its waterbodies. However, our study suggests that there exists areas and even water rich environments on Earth where no life is possible.

Distributed Poloidal Magnetic Field Measurement in Tokamaks Using Polarization-Sensitive Reflectometric Fiber Optic Sensor.

Determination of the poloidal magnetic field distribution in tokamaks is of prime importance for the successful operation of tokamaks. In this paper, we propose a polarization-sensitive reflectometry-based optical fiber sensor for measuring the spatial distribution of the poloidal magnetic field in tokamaks. The measurement method exploits the Rayleigh backscattering and Faraday magneto-optic effect in optical fibers.

Radiochemical and Biological Evaluation of 3p--NETA-ePSMA-16, a Promising PSMA-Targeting Agent for Radiotheranostics.

Bifunctional chelators (BFCs) are a key element in the design of radiopharmaceuticals. By selecting a BFC that efficiently complexes diagnostic and therapeutic radionuclides, a theranostic pair possessing almost similar biodistribution and pharmacokinetic properties can be developed. We have previously reported 3p--NETA as a promising theranostic BFC, and the encouraging preclinical outcomes obtained with [F]AlF-3p--NETA-TATE led us to conjugate this chelator to a PSMA-targeting vector for imaging and treatment of prostate cancer.

RENEB Inter-Laboratory Comparison 2021: Inter-Assay Comparison of Eight Dosimetry Assays.

Tools for radiation exposure reconstruction are required to support the medical management of radiation victims in radiological or nuclear incidents. Different biological and physical dosimetry assays can be used for various exposure scenarios to estimate the dose of ionizing radiation a person has absorbed. Regular validation of the techniques through inter-laboratory comparisons (ILC) is essential to guarantee high quality results.

Direct comparison of [F]AlF-NOTA-JR11 and [F]AlF-NOTA-octreotide for PET imaging of neuroendocrine tumors: Antagonist versus agonist.

Background: [F]AlF-NOTA-octreotide is an F-labeled somatostatin analogue which is a good clinical alternative for Ga-labeled somatostatin analogues. However, radiolabeled somatostatin receptor (SSTR) antagonists might outperform agonists regarding imaging sensitivity of neuroendocrine tumors (NETs). No direct comparison between the antagonist [F]AlF-NOTA-JR11 and the agonist [F]AlF-NOTA-octreotide as SSTR PET probes is available.

Experimental determination of soil sampling uncertainty in the context of environmental radiological monitoring.

Uncertainty associated with nuclear counting analyses are attributed to two main components of uncertainty; one is related to sampling, the other to sample preparation and the subsequent nuclear counting. The ISO/IEC 17025 standard of 2017 require accredited laboratories carrying out their own sampling to estimate the uncertainty associated with sampling in the field. This study presents the results of a sampling campaign and analysis by gamma spectrometry to determine the sampling uncertainty related to the measurement of radionuclides in soil.

Extremity exposure of nuclear medicine workers: results from an EANM and EURADOS survey.

Background: Extremity exposure during the handling of unsealed radioactive sources is a matter of concern for nuclear medicine workers. Next to Tc and F, other radiopharmaceuticals have seen an increase in their use over the last decade. However, limited information on their impact on extremity dose is available.

Exploring the Potential of High-Molar-Activity Samarium-153 for Targeted Radionuclide Therapy with [Sm]Sm-DOTA-TATE.

Samarium-153 is a promising theranostic radionuclide, but low molar activities (Am) resulting from its current production route render it unsuitable for targeted radionuclide therapy (TRNT). Recent efforts combining neutron activation of 152Sm in the SCK CEN BR2 reactor with mass separation at CERN/MEDICIS yielded high-Am 153Sm. In this proof-of-concept study, we further evaluated the potential of high-Am 153Sm for TRNT by radiolabeling to DOTA-TATE, a well-established carrier molecule binding the somatostatin receptor 2 (SSTR2) that is highly expressed in gastroenteropancreatic neuroendocrine tumors.

A simple and automated method for Tb purification and ICP-MS analysis of Tb.

Background: Tb is a radiolanthanide with the potential to replace Lu in targeted radionuclide therapy. Tb is produced via the neutron irradiation of [Gd]GdO targets, and must be purified from Gd and the decay product Dy prior to use. Established purification methods require complex conditions or high-pressure ion chromatography (HPIC) which are inconvenient to introduce in a broad user community.

A Review on Tumor Control Probability (TCP) and Preclinical Dosimetry in Targeted Radionuclide Therapy (TRT).

Targeted radionuclide therapy (TRT) uses radiopharmaceuticals to specifically irradiate tumor cells while sparing healthy tissue. Response to this treatment highly depends on the absorbed dose. Tumor control probability (TCP) models aim to predict the tumor response based on the absorbed dose by taking into account the different characteristics of TRT.

Gamma counting protocols for the accurate quantification of Ac and Bi without the need for a secular equilibrium between parent and gamma-emitting daughter.

Background: Quantification of actinium-225 through gamma counter measurements, when there is no secular equilibrium between actinium-225 and its gamma emitting daughters bismuth-213 and/or francium-221, can provide valuable information regarding the possible relocation of recoiled daughters such that related radiotoxicity effects can be evaluated. This study proposes a multiple time-point protocol using the bismuth-213 photopeak with measurements before secular equilibrium between actinium-225 and bismuth-213, and a single time-point protocol using both the francium-221 and bismuth-213 photopeak while assuming secular equilibrium between actinium-225 and francium-221 but not between bismuth-213 and actinium-225.

Results: Good agreement (i.

Simulation and experimental verification of ambient neutron doses in a pencil beam scanning proton therapy room as a function of treatment plan parameters.

Out-of-field patient doses in proton therapy are dominated by neutrons. Currently, they are not taken into account by treatment planning systems. There is an increasing need to include out-of-field doses in the dose calculation, especially when treating children, pregnant patients, and patients with implants.

EURADOS REM-COUNTER INTERCOMPARISON AT MAASTRO PROTON THERAPY CENTRE: COMPARISON WITH LITERATURE DATA.

The Maastro Proton Therapy Centre is the first European facility housing the Mevion S250i Hyperscan synchrocyclotron. The proximity of the accelerator to the patient, the presence of an active pencil beam delivery system downstream of a passive energy degrader and the pulsed structure of the beam make the Mevion stray neutron field unique amongst proton therapy facilities. This paper reviews the results of a rem-counter intercomparison experiment promoted by the European Radiation Dosimetry Group at Maastro and compares them with those at other proton therapy facilities.

Radiation adverse outcome pathways (AOPs) are on the horizon: advancing radiation protection through an international Horizon-Style exercise.

Purpose: The Adverse Outcome Pathway (AOP) framework, a systematic tool that can link available mechanistic data with phenotypic outcomes of relevance to regulatory decision-making, is being explored in areas related to radiation risk assessment. To examine the challenges including the use of AOPs to support the radiation protection community, an international horizon-style exercise was initiated through the Organisation for Economic Co-operation and Development Nuclear Energy Agency High-Level Group on Low Dose Research Radiation/Chemical AOP Joint Topical Group. The objective of the HSE was to facilitate the collection of ideas from a range of experts, to short-list a set of priority research questions that could, if answered, improve the description of the radiation dose-response relationship for low dose/dose-rate exposures, as well as reduce uncertainties in estimating the risk of developing adverse health outcomes following such exposures.