Crystal Nucleation in Supercooled Atomic Liquids.

The liquid-to-solid phase transition is a complex process that is difficult to investigate experimentally with sufficient spatial and temporal resolution. A key aspect of the transition is the formation of a critical seed of the crystalline phase in a supercooled liquid, that is, a liquid in a metastable state below the melting temperature. This stochastic process is commonly described within the framework of classical nucleation theory, but accurate tests of the theory in atomic and molecular liquids are challenging.

EURADOS project on the impact of the proposed ICRU operational dose quantities.

Following the publication of the joint The International Commissions on Radiation Units and Measurements (ICRU) and on Radiological Protection (ICRP) report on new operational quantities for radiation protection, the European Dosimetry Group (EURADOS) have carried out an initial evaluation. The EURADOS report analyses the impact that the new quantities will have on: radiation protection practice; calibration and reference fields; European and national regulation; international standards and, especially, dosemeter and instrument design. The task group included experienced scientists drawn from across the various EURADOS working groups.

Measurements in pulsed neutron fields.

Dosimetry in pulsed and mixed radiation fields represents an important challenge in radiation measurements, because in several accelerator technologies, the acceleration occurs in bunches of particles with short time duration, producing intense radiation pulses spaced by a relatively long time of beam off. The stray mixed radiation field generated around these installations maintains the same time structure as the primary beam and causes a problem in workplace fields' monitoring. Active neutron detectors normally used in steady neutron fields, specifically REM-counters and Bonner sphere spectrometers, can suffer pulsed fields because of the high dead time losses during the bursts and are often inadequate for pulsed field monitoring.

The EURADOS CR-39 Quality task for the optimisation and harmonisation of personal neutron dosimetry with CR-39 (PADC).

CR-39 (PADC) nuclear track detectors are among the most widespread devices used for personal neutron dosimetry; however, some issues related to the variable material quality of the CR-39 polymer hinder the performance of CR-39-based dosemeters. For this reason, the Working Group 2 (WG2) of the European Radiation Dosimetry Group (EURADOS) has recently launched the CR-39 Quality task, a project aimed at improving and harmonising personal neutron dosimetry with CR-39 in Europe. Whitin this task, a close collaboration among researchers, individual monitoring services and dosemeter grade CR-39 manufacturers is achieved, thus facilitating the direct dialog between producer and consumer to reach an optimised material for personal neutron dosimetry applications.

Calibration of the W-PIE neutron spectrometer at CERF reference facility.

The W-PIE is a cosmic neutron spectrometer used for environmental measurements, developed by Politecnico di Milano. The instrument is based on the Artkis M800 thermal neutron detector and works as a 4-channel spectrometer for detecting neutrons in the energy range of 0.01 eV-1 GeV.

Refractive Index of Supercooled Water Down to 230.3 K in the Wavelength Range between 534 and 675 nm.

Knowledge of the refractive index of water in the deeply supercooled metastable liquid state is important, for example, for an accurate description of optical reflection and refraction processes occurring in clouds. However, a measurement of both the temperature and wavelength dependence of the refractive index under such extreme conditions is challenging. Here, we employ Raman spectroscopy in combination with microscopic water jets in vacuum to obtain the refractive index of supercooled water to a lowest temperature of 230.

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.

Joint EURADOS WG9-WG11 rem-counter intercomparison in a Mevion S250i proton therapy facility with Hyperscan pulsed synchrocyclotron.

Objective Proton therapy is gaining popularity because of the improved dose delivery over conventional radiation therapy. The secondary dose to healthy tissues is dominated by secondary neutrons. Commercial rem-counters are valuable instruments for the on-line assessment of neutron ambient dose equivalent (H*(10)).

Impact of new operational dosimetric quantities on individual monitoring services.

The new operational dosimetric quantities framework, proposed in the ICRU95 report, has stimulated the scientific community to start investigations that aim to assess its impact on radiation protection practices. As part of this effort, the present study describes an inter-comparison exercise among individual monitoring services (IMSs) on passive whole-body dosimetry. The inter-comparison is performed in terms of both the existing operational dose quantityHp(10)and its proposed replacementHp, to allow an evaluation of the actions that may be necessary to adapt dosimetry systems to the proposed quantity.

EURADOS STRATEGIC RESEARCH AGENDA 2020: VISION FOR THE DOSIMETRY OF IONISING RADIATION.

Since 2012, the European Radiation Dosimetry Group (EURADOS) has developed its Strategic Research Agenda (SRA), which contributes to the identification of future research needs in radiation dosimetry in Europe. Continued scientific developments in this field necessitate regular updates and, consequently, this paper summarises the latest revision of the SRA, with input regarding the state of the art and vision for the future contributed by EURADOS Working Groups and through a stakeholder workshop. Five visions define key issues in dosimetry research that are considered important over at least the next decade.

The European Joint Research Project UHDpulse - Metrology for advanced radiotherapy using particle beams with ultra-high pulse dose rates.

UHDpulse - Metrology for advanced radiotherapy using particle beams with ultra-high pulse dose rates is a recently started European Joint Research Project with the aim to develop and improve dosimetry standards for FLASH radiotherapy, very high energy electron (VHEE) radiotherapy and laser-driven medical accelerators. This paper gives a short overview about the current state of developments of radiotherapy with FLASH electrons and protons, very high energy electrons as well as laser-driven particles and the related challenges in dosimetry due to the ultra-high dose rate during the short radiation pulses. We summarize the objectives and plans of the UHDpulse project and present the 16 participating partners.

EURADOS education and training activities.

This paper provides a summary of the Education and Training (E&T) activities that have been developed and organised by the European Radiation Dosimetry Group (EURADOS) in recent years and in the case of Training Courses over the last decade. These E&T actions include short duration Training Courses on well-established topics organised within the activity of EURADOS Working Groups (WGs), or one-day events integrated in the EURADOS Annual Meeting (workshops, winter schools, the intercomparison participants' sessions and the learning network, among others). Moreover, EURADOS has recently established a Young Scientist Grant and a Young Scientist Award.

COMPARISON OF PADC NEUTRON DETECTORS FROM DIFFERENT SUPPLIERS.

The objective of this study was to compare poly-allyl diglycol carbonate (PADC) track detectors from different suppliers for linear energy transfer (LET) spectrometry and neutron dosimetry. PADCs are commonly used for passive personal neutron dosimetry, where a common approach is to couple the PADC with a plastic radiator to generate secondary charged particles. The neutron dose can be estimated using the track density or the average LET of the secondary particles.

Alternative splicing of hTERT: a further mechanism for the control of active hTERT in acute myeloid leukemia.

hTERT component is the key regulator of telomerase. Alternatively spliced variants of hTERT generate different telomerase activity. The goal of the study was to determine the role of different hTERT isoforms in the regulation of telomerase expression in AML patients.

MDS/AML del(11)(q14) Share Common Morphological Features Despite Different Chromosomal Breakpoints.

In myelodysplatic syndromes and acute myeloid leukemia (MDS/AML) deletion of the 11q14 region is a rare chromosomal defect (incidence: 0.6-1.0%), included within the intermediate risk criteria by the International Prognostic Scoring System.

A new version of the LUPIN detector: improvements and latest experimental verification.

LUPIN-II is an upgraded version of LUPIN, a novel rem counter first developed in 2010 specifically conceived to work in pulsed neutron fields (PNFs). The new version introduces some modifications that improve the performance of the detector, in particular extending its upper detection limit in PNFs. This paper discusses the characteristics and the performance of the instrument.

Evaluation of a personal and environmental dosemeter based on CR-39 track detectors in quasi-monoenergetic neutron fields.

In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV.

A comparison of the response of PADC neutron dosemeters in high-energy neutron fields.

Within the framework of the EURADOS Working Group 11, a comparison of passive neutron dosemeters in high-energy neutron fields was organised in 2011. The aim of the exercise was to evaluate the response of poly-allyl-glycol-carbonate neutron dosemeters from various European dosimetry laboratories to high-energy neutron fields. Irradiations were performed at the iThemba LABS facility in South Africa with neutrons having energies up to 66 and 100 MeV.

Instrument intercomparison in the high-energy mixed field at the CERN-EU reference field (CERF) facility.

This paper discusses an intercomparison campaign performed in the mixed radiation field at the CERN-EU (CERF) reference field facility. Various instruments were employed: conventional and extended-range rem counters including a novel instrument called LUPIN, a bubble detector using an active counting system (ABC 1260) and two tissue-equivalent proportional counters (TEPCs). The results show that the extended range instruments agree well within their uncertainties and within 1σ with the H*(10) FLUKA value.

Comparison of the performance of different instruments in the stray neutron field around the CERN Proton Synchrotron.

This paper discusses an intercomparison campaign carried out in several locations around the CERN Proton Synchrotron. The locations were selected in order to perform the measurements in different stray field conditions. Various neutron detectors were employed: ionisation chambers, conventional and extended range rem counters, both commercial and prototype ones, including a novel instrument called LUPIN, specifically conceived to work in pulsed fields.

Detection of TET2 abnormalities by fluorescence in situ hybridization in 41 patients with myelodysplastic syndrome.

TET2 haplo-insufficiency occurs through different molecular mechanisms and is promptly revealed by array comparative genomic hybridization, single nucleotide polymorphism (SNP) array, and next-generation sequencing (NGS). Fluorescence in situ hybridization (FISH) can effectively demonstrate TET2 deletions and is often used to validate molecular results. In the present study 41 MDS patients with and without 4q abnormalities were analyzed with a series of bacterial artificial chromosome (BAC) probes spanning the 4q22.

Does cytogenetic evolution have any prognostic relevance in myelodysplastic syndromes? A study on 153 patients from a single institution.

The present study was designed to establish the incidence of cytogenetic evolution (CE), defined as the acquisition of chromosomal defects during the course of MDS, in order to correlate it with the WHO classification and IPSS score, and to assess its impact on overall survival (OS) and risk of MDS/AML evolution (progression-free interval, PFI) by means of Cox models for time-dependent covariates. Adjustments for known risk factors were achieved by performing a bivariable analysis. The study was carried out in 153 MDS patients who were followed for a median period of 45.

Double-differential spectra of secondary particles from hadrons on tissue equivalent targets.

Double-differential spectra generated by ions on tissue equivalent targets were calculated with the FLUKA code. Seven different species of ion beams were simulated, impinging onto an ICRU tissue equivalent target representing the chest of a patient under treatment. The following ion beams were investigated at an energy level capable of penetrating ICRU tissue up to a 26.

Sensitivity study of CR39 track detector in an extended range Bonner sphere spectrometer.

Bonner sphere spectrometers (BSS) are being used widely in neutron spectrometry since 1960. The response to neutrons of these moderating detectors spans over a broad energy range. This work discusses the measurement of the sensitivity of an extended range BSS hosting a CR39 nuclear track detector coupled to a boron converter.

World Health Organization classification in combination with cytogenetic markers improves the prognostic stratification of patients with de novo primary myelodysplastic syndromes.

This study correlated chromosomal defects with French-American-British (FAB)/World Health Organization (WHO) classification subtypes, proposed a revised International Prognostic Scoring System (IPSS) cytogenetic grouping; and established which classification, when used with the IPSS cytogenetic categories, best predicted clinical outcome in the myelodysplastic syndromes (MDS). A higher prevalence of chromosomal defects and distinct defects were observed in patients with multi-lineage dysplasia and a blast cell percentage >10%. Abnormalities of the long arm of chromosome 3, del(7)(q31q35), trisomy 8, del(11)(q14q23), del(12p) and 20q- could be segregated from their respective IPSS cytogenetic categories and used to develop new cytogenetic subgroups.