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A new large-volume metal reference standard has been developed. The intended use is for calibration of free-release radioactivity measurement systems and is made up of cast iron tubes placed inside a box of the size of a Euro-pallet (80 × 120 cm). The tubes contain certified activity concentrations of 60Co (0.290±0.006 Bq g1) and 110mAg (3.05±0.09 Bq g1) (reference date: 30 September 2013). They were produced using centrifugal casting from a smelt into which 60Co was first added and then one piece of neutron irradiated silver wire was progressively diluted. The iron castings were machined to the desirable dimensions. The final material consists of 12 iron tubes of 20 cm outer diameter, 17.6 cm inner diameter, 40 cm length/height and 245.9 kg total mass. This paper describes the reference standard and the process of determining the reference activity values. [ABSTRACT FROM AUTHOR]

Following the accident at the Daiichi Fukushima nuclear power plant in 2011, a vast number of Pacific seawater samples from many locations far from Fukushima have been collected by Japanese investigators. Due to dilution, the activities of radionuclides from North Pacific seawater samples are very low, which calls for extraordinary measures when being measured. This study focuses on the metrological aspects of the gamma-ray spectrometry measurements performed on such samples in two underground laboratories; at HADES (by JRC-IRMM in Belgium), and at Ogoya (by Kanazawa University in Japan). Due to many samples and long measurement times, all available HPGe detectors needed to be employed. In addition to single coaxial detectors, this involved multidetector systems and well detectors. Optimization of detection limits for different radionuclides and detectors was performed using Monte Carlo simulations.

Abstract: High-resolution alpha-particle spectrometry was performed with an ion-implanted silicon detector in vacuum on a homogeneously electrodeposited 236U source. The source was measured at different solid angles subtended by the detector, varying between 0.8% and 2.4% of 4π sr, to assess the influence of coincidental detection of alpha-particles and conversion electrons on the measured alpha-particle emission probabilities. Additional measurements were performed using a bending magnet to eliminate conversion electrons, the results of which coincide with normal measurements extrapolated to an infinitely small solid angle. The measured alpha emission probabilities for the three main peaks – 74.20 (5)%, 25.68 (5)% and 0.123 (5)%, respectively – are consistent with literature data, but their precision has been improved by at least one order of magnitude in this work. [Copyright &y& Elsevier]

Abstract: The alpha-particle emission probabilities associated with the three main alpha transitions of 238U were measured by high-resolution alpha-particle spectrometry. Highly enriched 238U material was used and its isotopic composition characterised by mass spectrometry. Source production through electrodeposition was optimised to reconcile conflicting demands for good spectral resolution and statistical precision. Measurements were performed at IRMM and CIEMAT for 1–2 years in three different set-ups. A new magnet system was put into use to largely eliminate true coincidence effects with low-energy conversion electrons. Finally the accuracy and precision of the relative emission probabilities for the three transitions – 77.01 (10)%, 22.92 (10)% and 0.068 (10)%, respectively – have been improved significantly. [Copyright &y& Elsevier]

Abstract: The half-lives of 221Fr, 217At, 213Bi, 213Po, and 209Pb were measured by means of an ion-implanted planar Si detector for alpha and beta particles emitted from weak 225Ac sources or from recoil sources, which were placed in a quasi-2π counting geometry. Recoil sources were prepared by collecting atoms from an open 225Ac source onto a glass substrate. The 221Fr and 213Bi half-lives were determined by following the alpha particle emission rate of recoil sources as a function of time. Similarly, the 209Pb half-life was determined from the beta particle count rate. The shorter half-lives of 217At and 213Po were deduced from delayed coincidence measurements on weak 225Ac sources using digital data acquisition in list mode. The resulting values: T 1/2(221Fr)=4.806 (6) min, T 1/2(217At)=32.8 (3)ms, T 1/2(213Bi)=45.62 (6)min, T 1/2(213Po)=3.708 (8)μs, and T 1/2(209Pb)=3.232 (5)h were in agreement only with the best literature data. [Copyright &y& Elsevier]

Abstract: In this work, 213Bi has been separated from an open 225Ac source by collecting recoil atoms onto a glass plate in vacuum. The activity of such recoil sources has been measured as a function of time, using an ion-implanted planar Si detector in quasi-2π geometry. From these measurements, a new half-life value of T 1/2(213Bi)=45.62 (6)min was derived. Additionally, high-resolution alpha-spectrometry measurements were performed at a solid angle of 0.4% of 4πsr, to verify the energies and emission probabilities of the α-emissions from 213Bi. Using 225Ac, 221Fr, 217At and 213Po peaks as reference peaks, the measured 213Bi α-peak energies at E α,0=5878 (4)keV and E α,1=5560 (4)keV were about 10keV higher than validated data. The relative α-particle emission probabilities of 213Bi, P α,0=0.9155 (11) and P α,1=0.0845 (11), and the 213Bi alpha branching factor, P α=1−P β=2.140 (10)%, are compatible with recommended values, but have a higher accuracy. [Copyright &y& Elsevier]

Abstract: The 225Ac half-life was determined by measuring the activity of 225Ac sources as a function of time, using various detection techniques: α-particle counting with a planar silicon detector at a defined small solid angle and in a nearly-2π geometry, 4πα+β counting with a windowless CsI sandwich spectrometer and with a pressurised proportional counter, gamma-ray spectrometry with a HPGe detector and with a NaI(Tl) well detector. Depending on the technique, the decay was followed for 59–141d, which is about 6–14 times the 225Ac half-life. The six measurement results were in good mutual agreement and their mean value is T 1/2(225Ac)=9.920 (3)d. This half-life value is more precise and better documented than the currently recommended value of 10.0d, based on two old measurements lacking uncertainty evaluations. [Copyright &y& Elsevier]

Abstract: High-resolution alpha-particle spectrometry was performed on the 230U decay series. A 230U source was prepared on a stainless steel disc by electrodeposition in an ammonium nitrate solution. Spectrometry of the alpha-particle energy spectrum was performed with ion-implanted planar silicon detectors in vacuum. A set of alpha emission probabilities is presented for 230U and 226Th. The measured peak intensities were corrected mathematically for coincidental detection of alpha-particles and conversion electrons emitted in the same decay. A good agreement with literature data was observed. The uncertainty budget and the correlation matrix are presented. The validity of the alpha-particle energies was tested and could be confirmed for most peaks within a few keV, but discrepancies were found for the 2nd peak of 226Th and the main peak of 218Rn. [Copyright &y& Elsevier]

Abstract: The half-lives of 226Th and 222Ra were measured by counting alpha-particle emissions from sources as a function of time. The 226Th sources were prepared from an open 230U source, capturing recoil atoms after alpha-particle decay on glass disks or even directly onto a detector. Similarly, the 222Ra sources were obtained by self-transfer of recoil atoms from 226Th sources. The activity measurements were performed in (nearly-)2π geometry with an ion-implanted silicon detector. The decay curves were analysed in different ways, incl. moment analysis, trying to avoid the pitfalls of bias of least-squares fits to Poisson distributed data. The observed half-life values are T 1/2(226Th)=30.70 (3) min and T 1/2(222Ra)=33.6 (4) s. Literature values show some inconsistency. [Copyright &y& Elsevier]

Abstract: The half-lives of 214Po and 218Rn have been measured. The radionuclides were produced in the decay of a 230U source and the emitted alpha-particles were measured in nearly-2π geometry with an ion-implanted planar silicon detector. The data acquisition was performed with a digitiser operated in list mode, saving the energy and time of detection (10ns precision timestamp) of each event. The half-lives were deduced from the time differences between the alpha-decays populating the nuclide of interest and those corresponding to its decay. Different methods were applied, based on delayed coincidence counting and time-interval distribution analysis. The resulting half-lives are 33.75 (15)ms for 218Rn and 164.2 (6)μs for 214Po, both in agreement with some of the literature values, and obtained with higher precision in this work. [Copyright &y& Elsevier]

Abstract: The 230U half-life was determined by measuring the decay curve of 230U sources by various nuclear detection techniques: α-particle counting at a defined small solid angle; 4πα+β counting with a windowless CsI sandwich spectrometer, a liquid scintillation counter and a pressurised proportional counter; gamma-ray spectrometry with a HPGe detector and nearly-2π α-particle counting with an ion-implanted silicon detector. Depending on the technique, the decay was followed for 100–200d, which is 5–10 times the 230U half-life. The measurement results of the various techniques were in good mutual agreement. The mean value, T 1/2(230U)=20.23 (2)d, is lower than the literature value which is based on one measurement in 1948 and resulted in a half-life value of 20.8d without statement of uncertainty. A correction for the ingrowth of the long-lived 210Pb and its daughter products may have been overlooked in the past. [Copyright &y& Elsevier]

The L6 chondritic meteorite, HaH-346, fell in Libya. However, neither the exact date of the fall nor the exact size of the original meteoroid or asteroid is known. A specimen of the meteorite, weighing 488 g, was measured using ultra low-background gamma-ray spectrometry in the 225 m deep underground facility HADES. Activation products 22 Na, 26 Al, 60 Co, 57 Co, 54 Mn and 44 Ti were detected. The detection efficiency was determined by 3D scanning the meteorite and introducing this in the computer model of the detector and sample implemented in the MCNP6.2 Monte Carlo code. The activities of 22 Na and 26 Al support the hypothesis that the fall took place on 26 August 2018. Furthermore, the 60 Co and 26 Al activities indicate that the original radius of meteoroid was between 50 and 80 cm, which suggests the mass prior to atmospheric entry was between 2400 and 7300 kg., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Zbigniew Tyminski reports equipment, drugs, or supplies was provided by European Commission Joint Research Centre (JRC)., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The term cutaneous pseudolymphoma (C-PSL) is defined in the literature as a benign, reactive lymphoproliferation that clinically and/or histopathologically imitates cutaneous lymphoma. The exact etiopathogenesis has not been fully elucidated to date. A distinction is made between primary, idiopathic PSL without an identifiable cause and secondary PSL with a known stimulus. We report the occurrence of pseudolymphoma after treatment with medicinal leeches (hirudotherapy). To the best of our knowledge, a total of only nine cases of cutaneous PSL after hirudotherapy have been reported in the literature to date., (© 2021. The Author(s).)

Interleukin-27 (IL-27) is an immunoregulatory cytokine that suppresses inflammation through multiple mechanisms, including induction of IL-10, but the transcriptional network mediating its diverse functions remains unclear. Combining temporal RNA profiling with computational algorithms, we predict 79 transcription factors induced by IL-27 in T cells. We validate 11 known and discover 5 positive (Cebpb, Fosl2, Tbx21, Hlx, and Atf3) and 2 negative (Irf9 and Irf8) Il10 regulators, generating an experimentally refined regulatory network for Il10. We report two central regulators, Prdm1 and Maf, that cooperatively drive the expression of signature genes induced by IL-27 in type 1 regulatory T cells, mediate IL-10 expression in all T helper cells, and determine the regulatory phenotype of colonic Foxp3 + regulatory T cells. Prdm1/Maf double-knockout mice develop spontaneous colitis, phenocopying ll10-deficient mice. Our work provides insights into IL-27-driven transcriptional networks and identifies two shared Il10 regulators that orchestrate immunoregulatory programs across T helper cell subsets., Competing Interests: Declaration of Interests A.R. is a founder and equity holder of Celsius Therapeutics, an equity holder in Immunitas Therapeutics, and, until August 31, 2020, an SAB member of Syros Pharmaceuticals, Neogene Therapeutics, Asimov, and Thermo Fisher Scientific. From August 1, 2020, A.R. is an employee of Genentech, a member of the Roche Group. V.K.K. has an ownership interest in Tizona Therapeutics, Celsius Therapeutics, and Bicara Therapeutics. V.K.K. has financial interests in Biocon Biologic, BioLegend, Elpiscience Biopharmaceutical Ltd., Equilium Inc., and Syngene Intl. V.K.K. is a member of SABs for Elpiscience Biopharmaceutical Ltd., GSK, Kintai Therapeutics, Repertoir Immune Medicines, Rubius Therapeutics, and Tizona Therapeutics. A.C.A. is a member of SAB for Tizona Therapeutics, Compass Therapeutics, Zumutor Biologics, ImmuneOncia, and Astellas Global Pharma Development Inc. A.C.A.’s and V.K.K.’s interests were reviewed and managed by the Brigham and Women’s Hospital and Partners Healthcare and A.R.’s interests by the Broad Institute and HHMI in accordance with their conflict of interest policies., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

We present a rare case of a 4-year-old girl suffering from a sclerotic lesion on the forehead as well as uveitis and epileptic seizures. The patient was diagnosed with linear scleroderma "en coup de sabre" (LSECDS). Faced with no gold standard for treatment of LSECDS with severe extracutaneous manifestations, the case was intensively discussed within an interdisciplinary team setting and successfully treated.

A pilot proficiency test (PT) on measurements of the massic activity of 222 Rn in drinking water was organised by JRC-Geel. Fourteen environmental radioactivity monitoring laboratories were invited to participate. The key aim of the study was to test, optimise and stream-line the complete process for conducting such a PT in order to perform a large scale Europe-wide PT in a robust manner. The process involved using all state-of-the art knowledge on sampling, transporting and measuring 222 Rn in water. It was found that the majority of the participants' results (92%) were within the ±15% reference range. The pilot-PT showed that the applied process was suitable and can be used for the large scale European PT planned for the third quarter of 2018., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The half-life of 55 Fe has been measured accurately by following the decay curve of three sources with a large pressurised proportional counter. An argon(90%)-methane(10%) mixture was used as counter gas, at atmospheric pressure (∼1 × 10 5  Pa) and at enhanced pressures of 5 × 10 5  Pa and 8 × 10 5  Pa (for 1 source), respectively. The first measurements were performed in 2001, but the experiment was executed more systematically between 2005 and 2018, covering a period of about 5 half-lives. The residuals from an exponential decay curve were of the order of 0.1% to 0.2% at 1 × 10 5  Pa, and 0.03% at 5 × 10 5  Pa and 8 × 10 5  Pa. The gain of stability with increased gas pressure was due to asymptotically reaching the maximum counting efficiency, resulting in lower sensitivity to pressure variations. The deduced half-life value of T 1/2 ( 55 Fe) = 1006.70 (15) d or 2.7563 (4) a is more accurate than other data in literature, which are mutually discrepant. It is consistent with previous measurements at JRC with an X-ray defined solid angle counter., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

A collimated source of 241 Am was scanned over the endcap of a 21 year old coaxial HPGe-detector that had spent about 75% of its life at room temperature (and the remaining time at 77 K). The detector response was recorded and used as a measure of the relative thickness of the top deadlayer. This thickness was not homogeneous and was thicker near to the outer surface of the crystal compared to the centre, which could be a result of increased diffusion of Li atoms during times the detector was kept at room temperature. The results were compared with two newer HPGe-detectors that proved to have homogeneous top deadlayers., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The European Commission's Joint Research Centre organizes proficiency tests (PT) on radon-in-water measurements. In order to optimize sampling, transport and measurement methods many tests and small scale proficiency tests have been performed. The waters from natural springs, wells were sampled on-site in glass bottles then transported cooled to the JRC and collaborating laboratories. For the material characterization standard measurement methods based on gamma-ray spectrometry, emanometry and liquid scintillation counting were used. The influence of sampling, transport and sample handling on radon-loss was tested and quantified. It was observed that parameters like container material, filling height, storage temperature and handling can lead to substantial measurement bias due to radon-loss. This high risk for radon-loss from samples can potentially be a general radioprotection problem as doses to the public may be underestimated. Regular air and road transport can be considered adequate means of transport as they have little influence on radon-loss if a suitable glass sample container with flexible cap is used and that it is completely filled. On the basis of this work, modifications to the related standard as best practices are also proposed., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Since a few years there are well-type HPGe-detectors with a small, point-like, anode contacts available commercially. This paper describes the characterisation of the first ultra low-background, so-called, SAGe™ well detector with regards to resolution and background performance. Inside a passive lead/copper shield in the underground laboratory HADES a background count rate of 690 ± 6d -1 (268 ± 3d -1 per kg Ge) was recorded 19 months after taking it underground., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Forty-eight samples made of CaF 2 , LiF and YVO 4 were placed inside the KSTAR Tokamak and irradiated by neutrons and charged particles from eight plasma pulses. The aim was to provide information for plasma diagnostics. Due to the short pulse durations, the activities induced in the samples were low and therefore measurements were performed in five low-background underground laboratories. Details of the underground measurements, together with data on the quality control amongst the radiometric laboratories, are presented., (Copyright © 2016. Published by Elsevier Ltd.)