bluuebunny/crossref_metadata_2025 huggingface dataset:
A Qualitative Validation of Two Diagrammatic Measures of Attachment	Network Structure
Authors: Freeman Harry , Abdellatif Musheera Anis , Gnimpieba Etienne Z.
Published: November 2021

Abstract. In two qualitative evaluation studies, we explored the construct validity of two diagrammatic measures of attachment network structure, including the Bull’s Eye diagrammatic technique and a significantly modified version, the Web-based Hierarchical Mapping Technique (WHMT). In the first study, 20 young adults completed a Bull’s Eye diagram followed by a semi-structured interview in which participants explained their placement of support figures in their diagrams. Interview transcripts were analyzed using theory-driven thematic analysis to determine the presence of attachment-related themes, including safe haven, secure base effect, and proximity maintenance. Findings indicated mixed support for the Bull’s Eye as a measure of attachment networks. Although attachment themes were dominant among participants who identified a parent as their primary attachment figure, this was not the case among participants who identified a peer as a primary attachment figure. Participant justifications for peer attachments relied on non-attachment themes, including identity exploration and companionship. In the second study, we applied the same qualitative method to investigate the WHMT. Saturation was reached sooner, and attachment themes were dominant for both parent and peered primary attachment. Findings support the construct validity of the WHMT as a new measure of attachment network composition and strength.
Slide‐Hold‐Slide Protocols and Frictional Healing in Discrete Element Method (DEM) Simulations of Granular Fault Gouge
Authors: Ferdowsi Behrooz , Rubin Allan M.
Published: November 2021

The empirical constitutive modeling framework of rate‐ and state‐dependent friction (RSF) is commonly used to describe the time‐dependent frictional response of fault gouge to perturbations from steady sliding. In a previous study (Ferdowsi & Rubin, 2020), we found that a granular‐physics‐based model of a fault shear zone, with time‐independent properties at the contact scale, reproduces the phenomenology of laboratory rock and gouge friction experiments in velocity‐step and slide‐hold (SH) protocols. A few slide‐hold‐slide (SHS) simulations further suggested that the granular model might outperform current empirical RSF laws in describing laboratory data. Here, we explore the behavior of the same Discrete Element Method (DEM) model in SH and SHS protocols over a wide range of sliding velocities, hold durations, and system stiffnesses, and provide additional support for this view. We find that, similar to laboratory data, the rate of stress decay during SH simulations is in general agreement with the “Slip law” version of the RSF equations, using parameter values determined independently from velocity step tests. During reslides following long hold times, the model, similar to lab data, produces a nearly constant rate of frictional healing with log hold time, with that rate being in the range of ∼0.5 to 1 times the RSF “state evolution” parameterb. We also find that, as in laboratory experiments, the granular layer undergoes log‐time compaction during holds. This is consistent with the traditional understanding of state evolution under the Aging law, even though the associated stress decay is similar to that predicted by the Slip and not the Aging law.
A novel geometry image to accurately represent a surface by preserving mesh topology
Authors: Zeng Sheng , Geng Guohua , Gao Hongjuan , Zhou Mingquan
Published: November 2021

Geometry images parameterise a mesh with a square domain and store the information in a single chart. A one-to-one correspondence between the 2D plane and the 3D model is convenient for processing 3D models. However, the parameterised vertices are not all located at the intersection of the gridlines the existing geometry images. Thus, errors are unavoidable when a 3D mesh is reconstructed from the chart. In this paper, we propose parameterise surface onto a novel geometry image that preserves the constraint of topological neighbourhood information at integer coordinate points on a 2D grid and ensures that the shape of the reconstructed 3D mesh does not change from supplemented image data. We find a collection of edges that opens the mesh into simply connected surface with a single boundary. The point distribution with approximate blue noise spectral characteristics is computed by capacity-constrained delaunay triangulation without retriangulation. We move the vertices to the constrained mesh intersection, adjust the degenerate triangles on a regular grid, and fill the blank part by performing a local affine transformation between each triangle in the mesh and image. Unlike other geometry images, the proposed method results in no error in the reconstructed surface model when floating-point data are stored in the image. High reconstruction accuracy is achieved when the xyz positions are in a 16-bit data format in each image channel because only rounding errors exist in the topology-preserving geometry images, there are no sampling errors. This method performs one-to-one mapping between the 3D surface mesh and the points in the 2D image, while foldovers do not appear in the 2D triangular mesh, maintaining the topological structure. This also shows the potential of using a 2D image processing algorithm to process 3D models.
The influence of vitality forms on action perception and motor response
Authors: Lombardi G. , Zenzeri J. , Belgiovine G. , Vannucci F. , Rea F. , Sciutti A. , Di Cesare G.
Published: November 2021

During the interaction with others, action, speech, and touches can communicate positive, neutral, or negative attitudes. Offering an apple can be gentle or rude, a caress can be kind or rushed. These subtle aspects of social communication have been named vitality forms by Daniel Stern. Although they characterize all human interactions, to date it is not clear whether vitality forms expressed by an agent may affect the action perception and the motor response of the receiver. To this purpose, we carried out a psychophysics study aiming to investigate how perceiving different vitality forms can influence cognitive and motor tasks performed by participants. In particular, participants were stimulated with requests made through a physical contact or vocally and conveying rude or gentle vitality forms, and then they were asked to estimate the end of a passing action observed in a monitor (action estimation task) or to perform an action in front of it (action execution task) with the intention to pass an object to the other person presented in the video. Results of the action estimation task indicated that the perception of a gentle request increased the duration of a rude action subsequently observed, while the perception of a rude request decreased the duration of the same action performed gently. Additionally, during the action execution task, accordingly with the perceived vitality form, participants modulated their motor response.
Iron-catalyzed alkyne–carbonyl metathesis for the synthesis of 6,7-dihydro-5H-dibenzo[c,e]azonines
Authors: Chakraborty Baitan , Jana Umasish
Published: November 2021

The synthesis of nine-membered rings via iron-catalyzed alkyne–carbonyl methathesis (ACM) is reported. Biaryl substrates containing alkyne and acetal units undergo intramolecular ACM to furnish the unexplored 6,7-dihydro-5H-dibenzo[c,e]azonines.
Recent developments in the synthesis of nitrogen-containing heterocycles from β-aminovinyl esters/ketones as CC–N donors
Authors: Xia Xiao-Feng , Niu Yan-Ning
Published: November 2021

The synthesis of nitrogen-containing heterocycles from β-aminovinyl esters(ketones) was reviewed according to the classification of the final heterocycle synthesis.
Early elimination of uremic toxin ameliorates AKI-to-CKD transition
Authors: Chen Jia-Huang , Chao Chia-Ter , Huang Jenq-Wen , Hung Kuan-Yu , Liu Shing-Hwa , Tarng Der-Cherng , Chiang Chih-Kang
Published: November 2021

Acute kidney injury (AKI)-related fibrosis is emerging as a major driver of chronic kidney disease (CKD) development. Aberrant kidney recovery after AKI is multifactorial and still poorly understood. The accumulation of indoxyl sulfate (IS), a protein-bound uremic toxin, has been identified as a detrimental factor of renal fibrosis. However, the mechanisms underlying IS-related aberrant kidney recovery after AKI is still unknown. The present study aims to elucidate the effects of IS on tubular damage and its involvement in the pathogenesis of AKI-to-CKD transition. Our results showed that serum IS started to accumulate associated with the downregulation of tubular organic anion transporter but not observed in the small-molecule uremic toxins of the unilateral ischemia–reperfusion injury (UIRI) without a contralateral nephrectomy model. Serum IS is positively correlated with renal fibrosis and binding immunoglobulin protein (BiP) and CAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) expression induction in the UIRI with a contralateral nephrectomy model (UIRI+Nx). To evaluate the effects of IS in the AKI-to-CKD transition, we administered indole, a precursor of IS, at the early stage of UIRI. Our results demonstrated IS potentiates renal fibrosis, senescence-associated secretory phenotype (SASP), and activation of endoplasmic reticulum (ER) stress, which is attenuated by synergistic AST-120 administration. Furthermore, we clearly demonstrated that IS exposure potentiated hypoxia–reperfusion (H/R) induced G2/M cell cycle arrest, epithelial–mesenchymal transition (EMT) and aggravated ER stress induction in vitro. Finally, the ER chemical chaperon, 4-phenylbutyric acid (4-PBA), successfully reversed the above-mentioned AKI-to-CKD transition. Taken together, early IS elimination in the early stage of AKI is likely to be a useful strategy in the prevention and/or treatment of the AKI-to-CKD transition.
No detection of SO2, H2S, or OCS in the atmosphere of Mars from the first two Martian years of observations from TGO/ACS
Authors: Braude A. S. , Montmessin F. , Olsen K. S. , Trokhimovskiy A. , Korablev O. I. , Lefèvre F. , Fedorova A. A. , Alday J. , Baggio L. , Irbah A. , Lacombe G. , Forget F. , Millour E. , Wilson C. F. , Patrakeev A. , Shakun A.
Published: November 2021

Context. The detection of sulphur species in the Martian atmosphere would be a strong indicator of volcanic outgassing from the surface of Mars.

Aims. We wish to establish the presence of SO2, H2S, or OCS in the Martian atmosphere or determine upper limits on their concentration in the absence of a detection.

Methods. We perform a comprehensive analysis of solar occultation data from the mid-infrared channel of the Atmospheric Chemistry Suite instrument, on board the ExoMars Trace Gas Orbiter, obtained during Martian years 34 and 35.

Results. For the most optimal sensitivity conditions, we determine 1σ upper limits of SO2 at 20 ppbv, H2S at 15 ppbv, and OCS at 0.4 ppbv; the last value is lower than any previous upper limits imposed on OCS in the literature. We find no evidence of any of these species above a 3σ confidence threshold. We therefore infer that passive volcanic outgassing of SO2 must be below 2 ktons day−1.
Commissioning the ATLAS Liquid Argon Calorimeter Phase-I Upgrade
Authors: Kay Ellis
Published: November 2021

Liquid argon (LAr) sampling calorimeters are employed by ATLAS for all electromagnetic calorimetry in the pseudo-rapidity region η < 3.2, and for hadronic and forward calorimetry in the region from η = 1.5 to η = 4.9. In the first LHC run (Run-1), a total luminosity of around 26 fb-1 was collected at centre-of-mass energies of 7-8 TeV. After detector consolidation during a long shut-down, Run-2 started in 2015 and around 150 fb-1 of data at a centre-of-mass energy of 13 TeV was recorded. With the end of Run-2 in 2018, a multi-year shutdown for the Phase-I detector upgrades began. As part of the Phase-I upgrade, new trigger readout electronics of the ATLAS LAr Calorimeter have been developed. Installation be-gan at the start of the LHC shut down in 2019 and is expected to be completed in 2020. A commissioning cam-paign is underway in order to realise the capabilities of the new, higher granularity and higher precision level-1 trigger hardware in Run-3 data taking. This contribution will give an overview of the new trigger readout system and the ongoing commissioning and installation efforts.
Data Acquisition System Prototype of the ITER Diagnostic Divertor Neutron Flux Monitor Testing at Research Nuclear Facilities
Authors: Martazov E.S. , Paryshkin Yu.A. , Selyaev N.A. , Fedorov V.A. , Vorobev V.A. , Dzhurik A.S. , Kashchuk Yu.A. , Obudovsky S.Yu. , Bulavin M.V.
Published: November 2021

The Divertor nuclear flux monitor (DNFM) is one of the ITER neutron diagnostics. This diagnostic consists of the three same subsystems. Each subsystem concludes the detector module with fission chambers (FCs) and the data acquisition system (DAQ). To solve the task of the neutron flux measurements in the range of 7 orders of magnitude and 1 ms of time resolution the multidetector module is used. To confirm the possibility of the neutron flux measurements in a wide range using such a detector module and to evaluate the characteristics of the DAQ prototype a number of tests were carried out under conditions of the intense neutron radiation. The detector module and the DAQ, which are the prototype of the equipment planned for use on site were used for the tests. The tests were carried out at the plasma neutron diagnostic stand based on the NG-24M neutron generator and at the IBR-2 pulsed reactor of the Joint Institute for Nuclear Research. During the tests at the plasma neutron diagnostic stand the data for the calibration of the DNFM DAQ measuring channels were collected. During the tests at the IBR-2 pulsed reactor the signals from the measuring channels of the DNFM subsystem were obtained while the neutron flux was changed. This report shows the test results and the subsystem calibration techniques.
PISTIL, a reactivity modulation device to probe the transfer function of the nuclear reactor CROCUS
Authors: Jiang Yifeng , Geslot Benoit , Lamirand Vincent , Leconte Pierre , Godat Daniel , Braun Laurent , Frajtag Pavel , Coquelet-Pascal Christine , Pautz Andreas
Published: November 2021

The present article summarizes the development and testing of a reactivity modulation device developed by the French Atomic and Alternative Energies Commission (CEA). It was installed in the CROCUS reactor of the Swiss Federal Institute of Technology in Lausanne (EPFL). Experimental tests were performed in the framework of a collaboration between CEA and EPFL.

The so-called PISTIL device aims at measuring the nuclear reactor transfer function in the frequency range of interest between 1 mHz and 200 Hz, in order to probe the in-core kinetic behavior of prompt and delayed neutrons. The reactivity modulation is obtained from the rotation of cadmium foils.

The design of the system was driven with the objective of installing PISTIL at the center of the CROCUS reactor. Neutronic simulations with TRIPOLI-4 Monte Carlo code were performed to select the suitable design parameters and meet the safety requirements of the reactor operation.

The total reactivity worth of the device, as estimated by TRIPOLI-4 Monte Carlo calculation, was approximately 0.16 $ and the maximum amplitude of the reactivity modulation was about 0.013 $. In-core reactivity calibration was then performed and were consistent as compared to TRIPOLI-4 estimations.
Confocal chromatic sensor for displacement monitoring in research reactor
Authors: Agoyan Marion , Fourneau Gary , Cheymol Guy , Ladaci Ayoub , Maskrot Hicham , Destouches Christophe , Fourmentel Damien , Gérand Sébastien , Gaillard-Groléas Jérôme , Desjacques Matthieu , Girard Sylvain , Boukenter Aziz
Published: November 2021

Confocal chromatic microscopy is an optical technique allowing measuring displacement, thickness, and roughness with a sub-micrometric precision. Its operation principle is based on a wavelength encoding of the object position. Historically, the company STIL based in the south of France has first developed this class of sensors in the 90’s. Of course, this sensor can only operate in a sufficiently transparent medium in the used spectral domain. It presents the advantage of being contactless, which is a crucial advantage for some applications such as the fuel rod displacement measurement in a nuclear research reactor core and in particular for cladding-swelling measurements. The extreme environmental conditions encountered in such experiments i.e. high temperature, high pressure, high radiations flux, strong vibrations, surrounding turbulent flow can affect the performances of this optical system. We then need to implement mitigation techniques to optimize the sensor performance in this specific environment. Another constraint concerns the small volume available in the irradiation rig next to the rod to monitor, implying the challenge to conceive a miniaturized sensor able to operate under these constraints.
First in-core gamma spectroscopy experiments in a zero power reactor
Authors: Pakari Oskari , Lamirand Vincent , Mager Tom , Laureau Axel , Frajtag Pavel , Pautz Andreas
Published: November 2021

Gamma rays in nuclear reactors, arising either from nuclear reactions or decay processes, significantly contribute to the heating and dose of the reactor components. Zero power research reactors offer the possibility to measure gamma rays in a purely neutronic environment, allowing for validation experiments of dose estimates, computed spectra, and prompt to delayed gamma ratios. The resulting data can contribute to models, code validation and photo atomic/nuclear data evaluation. To date, most experiments have relied on flux measurements using TLDs, ionization chambers, or spectrometers set in low flux areas. The CROCUS reactor allows for flexible detector placement in and around the core, and has recently been outfitted with gamma detection capabilities to fulfill the need for in-core gamma spectroscopy, as opposed to flux. In this paper we report on the experiments and accompanying simulations of gamma spectrum measurements inside a zero power reactor core, CROCUS. It is a two-zone, uranium-fueled light water moderated facility operated by the Laboratory for Reactor Physics and Systems Behaviour (LRS) at the Swiss Federal Institute of Technology Lausanne (EPFL). Herein we also introduce, in detail, the new LEAF system: A Large Energy-resolving detection Array for Fission gammas. It consists of an array of four detectors – two large ø 127 254 mm Bismuth Germanate (BGO) and two smaller ø 12 50 mm Cerium Bromide (CeBr3) scintillators. We describe the calibration and characterization of LEAF followed by first in-core measurements of gamma ray spectra in a zero power reactor at different sub-critical and critical states, and different locations. The spectra are then compared to code results, namely MCNP6.2 pulse height tallies. We were able to distinguish prompt processes and delayed peaks from decay databases. We present thus experimental data from hitherto inaccessible core regions. We provide the data as validation means for codes that attempt to model these processes for energies up to 10 MeV. We finally draw conclusions and discuss the future uses of LEAF. The results indicate the possibility of isotope tracking and burn-up validation.
Local and high distance neutron and gamma measurements of fuel rods oscillation experiments
Authors: Lamirand Vincent , Pakari Oskari , Vitullo Fanny , Ambrožič Klemen , Godat Daniel , Frajtag Pavel , Pautz Andreas
Published: November 2021

We report in the present article on the successful observation using noise analysis of the lateral oscillation of one fuel rod by ±2.5 mm around nominal at 0.1 Hz frequency, using an mm3miniature neutron scintillatorat the rod level, and a BGO gamma detectorseven meters away from the reactor core center. The experiment was conducted as part of the COLIBRI program in the CROCUS reactor, which is dedicated to the investigation of reactor noise induced by fuel vibrations. It consists in experiments on rod lateral displacement (static) and oscillation (dynamic) with different rods’ numbers at various relevant amplitudes and frequencies. Its main motivation is the increased amplitudes in the neutron noise distributions recorded in ex- and in-core detectors that have been observed in recent years in Siemens pre-Konvoi type of PWR reactors. The obtained experimental data are used for the purpose of code validation, especially within the framework of the European project CORTEX on reactor noise applications. During the first phase of COLIBRI, the observation of a spatial dependence of the perturbation noise, also called neutron modulation, was demonstrated. In the second phase of COLIBRI starting 2021, it is planned to use a core mapping array of neutron detectors to record its propagation. It consists in about 150 miniature scintillators coupled to optical fibers and SiPM readouts, to be distributed in the reactor core. As a feasibility test, experiments were performed using a miniature scintillator prototype placed on a fuel rod, and oscillating the instrumented rod or the one directly adjacent to the detector. In addition, it is theoretically possible to measure branching or perturbation reactor noise using gamma radiation. Following recent developments on gamma measurements in CROCUS, the fuel oscillation was simultaneously recorded with a gamma detection array, LEAF. Its large BGO detectors were used by placing them at the maximum distance to the core, i.e. seven meters away with a clear line of sight using an experimental channel through the shielding of the reactor cavity.
Position evaluation of ex-core neutron flux measurement in new type graphite reactors
Authors: Vilimova Eva , Peltan Tomas , Skoda Radek
Published: November 2021

Several concepts of new reactors use graphite. Some of them use graphite as a moderator, some of them as a reflector. There are at least two concepts of these graphitetype reactors under development in the Czech Republic. Both reactors use graphite as the reflector. An in-core measurement might be impossible to use because of various reasons, for instance, high temperature or aggressive environment. Therefore, this article focuses on ex-core neutron flux measurement system placed in the graphite reflector and the optimization of ex-core detector position. A set of experiments were performed at LR-0 reactor. The LR-0 is a light water reactor with a well-defined neutron field, which can be used for different material insertion tests and testing of its influence on criticality. Several modifications of LR-0 cores were modelled in Monte Carlo codes Serpent and KENO. A set of calculations were performed for verification of the criticality and neutron flux course in the reactor core and graphite reflector. Further investigation was focused on the influence of the presence of a graphite reflector on the neutron distribution in the reactor core. The LR-0 graphite experiments were also used to verify the calculations. Based on the results of this article, the optimal position of ex-core detectors in the graphite reflector is proposed.
Analysis of the Signal over Noise Ratio of the hodoscope determined by Monte Carlo calculation
Authors: Di Salvo J. , Mirotta S. , Chevalier V.
Published: November 2021

The CABRI experimental pulse reactor, located at the Cadarache nuclear research center, southern France, is devoted to the study of Reactivity Initiated Accidents (RIA) for the purpose of the CABRI International Program (CIP), managed by IRSN in the framework of an OECD/NEA agreement. The hodoscope equipment installed in the CABRI reactor is an almost unique online fuel motion monitoring system, thanks to the measurement of the fast neutrons emitted during a power pulse by a tested rod positioned inside a dedicated test loop reproducing PWR conditions. This system is dedicated to the analysis of fuel displacement. Hence, one of the most important parameter measured by the hodoscope detectors is the Signal over Noise Ratio (SNR), characterizing the fraction of neutrons directly coming from the test rod (“signal”) over neutrons coming from the core (“noise”).

It is interesting to calculate the SNR in order to define some quantitative criterions to improve hodoscope measurements and to understand if any modification linked to the test loop may significantly change this essential parameter.

Another parameter of interest is the so-called “scattering coefficient”, which corresponds to the fraction of neutrons coming from the test rod and being scattered between their birth and their detection. This parameter is used to enhance the analysis of the fuel displacement which may happen during the power transient.

In this article, the method used to calculate the SNR using MCNP6.2 Monte Carlo code will be detailed. Because the hodoscope detectors are located far away from the test rod (up to 4 meters), a 2D model of CABRI core and instrumentation has been implemented. No variance reduction techniques have been used to solve this problem in order to record the place of birth of neutron which contributes to the different scores with the goal to perform a detailed analysis of the SNR. This strategy allows to access numerically to the “scattering coefficient”.

Finally, the comparison between calculated and measured SNR for a case study will be carried out. A quite good agreement between the 2D simulations and experiments recently performed in the CABRI reactor has been obtained.
Long-term Transmission Characteristics of CYTOP Fiber Exposed to Gamma Radiation
Authors: Chapalo Ivan , Gusarov Andrei , Kinet Damien , Chah Karima , Nan Ying-Gang , Mégret Patrice
Published: November 2021

We investigated post-irradiation variations of the radiation induced attenuation (RIA) of polymer perfluorinated (CYTOP) optical fiber exposed to gamma radiation. The RIA measured five months after the irradiation was qualitatively similar to that measured several hours after irradiation. However, quantitatively the RIA post-irradiation evolution significantly depends on the spectral range: in the visible range, the transmission partly recovers, while in the infrared, at wavelengths above 1300 nm the RIA grows and then saturates becoming permanent. The latter feature is prospective for gamma radiation dosimetry as a permanent long-term indicator of received radiation dose.
Toward UO2 micro/macro machining: a laser processing approach
Authors: Doualle Thomas , Reymond Matthieu , Pontillon Yves , Gallais Laurent
Published: November 2021

Linked to experimental data acquisition and to development of improved models, a better detailed description of the behaviour of the nuclear ceramics as regard to the fission gases release during thermal transient representative of nuclear accidents such as RIA (Reactivity Initiated Accident) and or LOCA (LOss of Coolant Accident) requires access to local information within the fuel pellet, and no longer averaged over the whole of the pellet. One of the major challenge in this context is the sample size, which depends on the main objective of the study, typically from the order of a few hundred microns to millimeters. Few techniques allow this dynamic while being compatible with irradiated fuel constraints. Laser micromachining is a high precision non-contact material removal process that would be adapted to this dynamic. We present experimental and numerical studies, carried out in order to evaluate the possibility to apply this process for the preparation of irradiated UO2 samples of various dimensions. First, preliminary experimental and numerical works conduced on graphite, as model material, which have comparable properties (in particular their behaviours under laser irradiation and their melting point) in order to validate the feasibility, will be detailed. Afterwards, based on these results, we present our first results on UO2. The objective is to transfer the technique to non-irradiated UO2 and then to the irradiated material.
Tests of Various Scintillator Detectors in Selected Mono-Energetic Neutron Beams
Authors: Jančář Aleš , Čulen Jiří , Mravec Filip , Košťál Michal , Dlhopolček Daniel , Pirovano Elisa , Nolte Ralf , Cvachovec František , Přenosil Václav , Matěj Zdeněk
Published: November 2021

In this paper we study quality of three types of organic scintillators stilbene, p-terphenyl and EJ-299-33. We used monoenergetic neutron fields with a wide range of neutron energies in PTB Braunschweig. All the tests were carried out with NGA-01 spectrometer. The results of the measurements are evaluated spectra from the spectrometer.

We discuss the quality of each scintillator, such as the FWHM of the peaks.
Study of natural uranium fuel for a new reactor design TEPLATOR
Authors: Peltan Tomas , Vilimova Eva , Skoda Radek
Published: November 2021

The TEPLATOR is a new type of nuclear reactor which the main purpose is producing heat for district heating. It is designed as a special thermal reactor with 55 fuel channels for fuel assemblies, which is moderated and cooled by heavy water and operated around atmospheric pressure. The TEPLATOR DEMO is designed for the use of irradiated fuel from PWR or BWR reactors. Using heavy water as the moderator and coolant in this reactor concept allows to use natural uranium as an alternative fuel in case that the irradiated fuel is not available for some reason. This solution is suitable because of the price of natural uranium and the absence of costly fuel enrichment. This article is focused on deeper analyses of alternative suitable fuel for TEPLATOR based on natural uranium and new fuel geometries. This work builds on previous research on alternative fuel material and geometry for the TEPLATOR. It is mainly concerned with the neutronic development of fuel assemblies, the possibility of manufacturing of developed fuel types, and optimization of fuel management and uranium consumption. This article contains predetermined candidates for suitable fuel geometries and new untested fuel geometry types with some new advantages. Finally, optimization of the whole reactor core and number of fuel channels was made in terms of increased safety and higher fuel burn-up. Presented calculations were performed by Monte Carlo code Seprent.
The Mini Labyrinth – a Simple Benchmark for Radiation Protection and Shielding Analysis
Authors: Vrban Branislav , Čerba Štefan , Osuský Filip , Lüley Jakub , Nečas Vladimír , Katovský Karel , Štastný Ondrej , Gloginjić Marko , Erich Marko , Mravik Željko , Petrović Srdjan
Published: November 2021

The Mini Labyrinth experiment is a simple neutron and gamma shielding experiment developed at STU, inspired by the ALARM-CF-AIR-LAB-001 ICSBEP benchmark experiment. The STU Mini Labyrinth is approximately ten times smaller and consists of NEUTRONSTOP shielding blocks. This paper describes the second version of the Mini Labyrinth experiment and presents the results of the neutron and gamma fields simulation and measurement. The PuBe neutron source with the emission rate of 1.0E7 n.s-1 was utilized in the experiment. The measurement of gamma ambient dose equivalent H*(10) and neutron count rates is performed by the Thermo Scientific RadEye portable survey meter. The simulation part was carried out using the state-of-the-art MCNP6 and SCALE6 MONACO stochastic calculation tools taking into account the detailed geometry of the labyrinth and a combined neutron and gamma source of particles. The comparisons were performed between codes and an experiment, based on the dose rate in the unique detection positions and using a 2D map of neutron and photon fluxes. The propagation of cross-section uncertainties was investigated through the shielding analysis. Partial agreement between codes and measurement was achieved, however serious discrepancies near the PuBe source were identified.
An advanced blind-tube monitoring instrument to improve the characterization of subsurface radioactive plumes
Authors: Elísio Soraia , Joyce Malcolm J. , Graham James , Greenhalgh Barrie
Published: November 2021

This research presents a design of a resilient blind-tube radiometric logging probe, which satisfies key, operational site constraints, for direct in-situ characterization of subsurface radioactivity, particularly caesium-137 and strontium-90. The probe comprises a commercially-available Ø10 mm × 9.5 mm CeBr3 scintillator detector attached to a compact digitizer unit, in a resistant and waterproof housing. The probe is designed to be lowered down into metallic Ø 75 mm blind-tubes by means of a winch system.
Active Dosimetry with the Ability to Distinguish Pulsed and Non-Pulsed Dose Rate Contributions
Authors: Makarevich Krystsina , Beyer Roland , Henniger Jürgen , Ma Yuzhen , Polter Sarah , Sommer Marian , Teichmann Tobias , Weinberger David , Kormoll Thomas
Published: November 2021

This paper presents the concept of an active dosimetry system and its operational regime for pulsed radiation dose rate measurements. The plastic scintillator is suggested to be used for absorbed dose rate measurements. As long as the detector can be considered tissue equivalent, the energy weighting of pile-up events in terms of the dose is achieved. The real-time distinction of pulsed and non-pulsed dose rate contributions is based on the time structure of a single interaction and requires only basic information about the beam time structure (pulses duration and period). The detector connected to a fully digital signal processing board creates an active dosimetry system with adjustable parameters. Such a system was used for absorbed dose rate measurements in pulsed photon field mimicking radiation field outside the bunker of a medical LINAC, but also in the presence of a constant radiation component. The results show a linear dependence of a pulsed radiation contribution on the accelerator current in the investigated range of the total dose rate up to 8 μGy/h.
Dose Rate Measurements in Pulsed Radiation Fields by Means of an Organic Scintillator
Authors: Werner Theresa , Beyer Roland , Biedermann Richard , Gerber Marko , Götze Jürgen , Herzig Philipp , Melzer Vincent , Metzner Elena , Weinberger David , Kormoll Thomas
Published: November 2021

A deficiency in the implementation of current radiation protection is the determination of the ambient dose equivalent H*(10) and the directional dose equivalent H´(0.07) in pulsed radiation fields. Conventional dosimeter systems are not suitable for measurements in photon fields comprising short radiation pulses, which consequently leads to high detector loads in short time periods. Nevertheless, due to the implementation of advanced medical accelerators for cancer therapy, new medical diagnostic devices as well as various laser machining systems, there is an urgent need for suitable dosimeter systems for real time dosimetry. In this paper, a detector concept based on an organic scintillator and a full digital data analysis with the aim of developing a portable, battery powered measurement system is presented.
Pulse shape simulations for organic scintillation detectors using Geant4
Authors: Holroyd Caroline , Aspinall Michael , Deakin Tom
Published: November 2021

The accurate simulation of the temporal pulse shapes from organic scintillation detectors capable of pulse shape discrimination (PSD) presents the opportunity to assess the pulse shape discrimination of these detectors prior to fabrication. The aim of this study is the simulation of the temporal pulse shapes from EJ-276, a PSD-capable plastic scintillator developed by Eljen Technologies. PSD plastic scintillators are increasingly replacing organic liquid scintillators for the detection of neutrons in the presence of mixed radiation fields for nuclear security applications. Plastics are inexpensive, robust and can be fabricated in a variety of shapes and sizes. They offer a solid-state alternative to liquid scintillators which can be difficult to transport due to the risk of leakage. However, the PSD performance of plastic scintillators has been observed to decrease due to various factors which combine to influence the overall shape of the pulse. The Monte Carlo toolkit Geant4 has been used to simulate the temporal pulse shapes from an EJ-276 plastic scintillator coupled to a photomultiplier tube (PMT). All three decay time components of EJ-276 have been modelled, utilising new methods available in the latest version of Geant4, for two different scintillator geometries. The simulated n/γ pulse shapes reproduce the features important for PSD. Future work will involve integrating the temporal response of the PMT with existing pulse shape simulations. Simulated data will then be compared with experimental measurements.
Development of a position-sensitive fast scintillator (LaBr3(Ce)) detector setup for gamma-ray imaging application
Authors: Das Biswajit , Palit R. , Donthi R. , Kundu A. , Laskar S. R. , Dey P. , Negi D. , Babra F. S. , Jadhav S. , Naidu B. S. , Vazhappilly A. T.
Published: November 2021

We have characterized a Cerium doped Lanthanum Bromide (LaBr3(Ce) ) crystal coupled with the position-sensitive photo-multiplier system for the gamma-ray imaging application. One can use this detector set-up for the scanning of high purity germanium detectors for pulse shape analysis in gamma-ray spectroscopy experiments and the image formation of an object by Compton back-scattering . The sensor has been tested for energy, timing and position information of the gamma-rays interacting within the detector crystal. The GEANT4 simulation results are consistent with the experimental results. We have reconstructed the image of irradiation spots in different positions throughout the detector crystal. Position resolution is found to be around 3.5 mm with the 2 mm collimated gamma-rays. The 2-d image of hexagonal Bismuth Germanate (BGO) crystal and a cylindrical LaBr3(Ce) crystal have been reconstructed in coincidence technique. The performance of the detector for imaging application has been investigated by coincidence technique in GEANT4 simulation and compared with the experimental data. We have reconstructed the 2-d images of objects with various geometrical shapes by Compton back-scattered events of the gamma-rays. This position-sensitive detector can be used as an absorber of a Compton camera for the image reconstruction of an extended radioactive source. One can also use this kind of set-up as in radiation imaging and many other applications where the energy and source position of the gamma-ray is the main interest.
Spectral Enhancement of a SiPM Array-Based Radiation Detector
Authors: Harn R. , Osovizky A. , Kadmon Y. , Rotman S. , Kopeika N. , Ghelman M.
Published: November 2021

Silicon Photomultipliers (SiPMs) have many advantages when used in radiation detectors. Low bias voltage, compactness and immunity to electromagnetic interference are among their prominent benefits. However, due to their small size, usually an array of SiPM components is required in order to cover the coupling surface area of a scintillator. Since the SiPM is a semiconductor, biased in a reversed voltage, gain variation and strong temperature dependence are introduced. As a result, SiPM-based detectors, particularly an array of SiPMs, undergo spectral signal to noise ratio reduction. This work studies the effect of the SiPM breakdown voltage variation on the obtained energy spectrum and proposes an electronic approach to overcome this technological drawback. This developed technology provides an adequate temperature-dependent, commonly distributed high bias voltage and an individual offset-voltage fine tuning that enables adjustment of all the SiPM components to their optimum operating points. Powerwise it is beneficial to operate SiPM at lower voltages, where undesirable gain variation is more dominant. The proposed solution enables working at lower bias voltages, which provides lower power consumption and better radiation hardness, while yielding an enhanced spectrum resolution. The proposed electronic approach enhances the obtained spectra, reducing the noise threshold by 16 % when working at 1 V overvoltage. Hence provides an enhanced signal to noise ratio over the traditional biasing methods.
Hidden statistics in speckle patterns
Authors: Carminati Rémi
Published: November 2021

Scattering of coherent light from a disordered material produces a complex distribution of intensity known as a speckle pattern. Speckle patterns are not as random as they appear at first glance. Their statistical properties exhibit universal features, as already recognized in the first paper on laser speckle. The existence of short-range and long-range spatial correlations in speckles has been shown to be fundamental in wave physics. It has also led to the emergence of novel approaches for imaging through scattering media.
Optical parametric oscillators
Authors: Melkonian Jean-Michel , Dherbecourt Jean-Baptiste , Raybaut Myriam , Godard Antoine
Published: November 2021

Optical parametric oscillators are versatile devices for generating a tunable coherent radiation from an incident laser beam. They rely on nonlinear frequency conversion to cover spectral ranges that are poorly or not covered by direct laser emission. This article presents a short overview of the optical parametric oscillators principles of operation, main implementations and related applications.
Projet Mecavision 21/23 : la méga vision pour l’emploi de l’entreprise Monnot
Authors: Crampon Cécile
Published: November 2021

Monnot est une entreprise familiale de mécanique implantée à Beaune, en Côte-d’Or, depuis 1934. Monnot est reconnue dans la production de pièces mécaniques complexes, l’usinage de réparation/maintenance, l’accompagnement de projets industriels et la conception de machines-outils à destination de la tonnellerie. Parmi ses clients, Monnot compte notamment le CEA qui a soutenu la PME pour participer à l’Appel à projets (AAP) de France Relance. Son projet retenu, Monnot savoure cette joie immense qui va lui permettre d’étaler son business plan sur trois ans au lieu de dix initialement.
Velan : robinetterie nucléaire et maintenance prévisionnelle
Authors: Le Gros Gaïc
Published: November 2021

Le projet « Vanne connectée » de Velan vise à associer les équipements de robinetterie à des solutions numériques pour optimiser les opérations de maintenance sur les réacteurs nucléaires. Un gain important de sûreté et de compétitivité.
Herpes-zoster-Update – was gibt es Neues?
Authors: Müller Cornelia S.L. , Bialas Patric , Becker Sören L.
Published: November 2021

Shingles are triggered by the reactivation of an infection with the varicella zoster virus (VZV) and are characterized by specific vesicular skin lesions. Mostly, elderly patients are affected. Depending on the affected dermatome, some serious complications can be observed. The introduction of a vaccine against shingles in Germany offers a great potential for reducing the frequency and severity of this disease. There are both a live vaccine, which is no longer recommended, and an inactivated vaccine, which, however, is still not sufficiently recommended to the authorized patient groups and is also only available to a limited extent due to delivery bottlenecks. HZ neuralgia is a serious complication of the disease that requires rapid and effective therapy and should be handed over to experienced pain therapists rather too early than too late. Unfortunately, in everyday clinical practice only a few people are familiar with VZV vasculopathy, which is associated with a significantly increased risk of cerebral insults.
Pflegestandard Demenz
Authors: Schmidt Simone
Published: November 2021

Beziehungsgestaltung ist das Kernelement der psychiatrischen Pflege – nicht nur, aber vor allem bei Menschen mit Demenz. Welche Faktoren dabei zu beachten sind und wie Pflegende eine personzentrierte Haltung entwickeln, erläutert unsere Autorin anhand des Expertenstandards „Beziehungsgestaltung in der Pflege von Menschen mit Demenz“.
Zehn Jahre Hautkrebsscreening in Deutschland – Leuchtturmfunktion, Probleme und Verbesserungsansätze – Daten einer großen Hautarztpraxis
Authors: Ziegler P.
Published: November 2021

Von 2008–2018 wurden ca. 40 000 Hautkrebsscreenings durchgeführt und die Daten analysiert. Es zeigte sich zum einen eine hochsignifikant steigende Zunahme von epithelialen malignen Tumoren um mehr als das Doppelte zwischen 2009–2018. Bei Patienten des gesetzlichen Hautkrebsscreenings konnte bei jedem 10. Patienten „weißer Hautkrebs“ diagnostiziert werden, 1,2 % der Patienten litten unter einem malignen Melanom, wobei 50 % davon in situ waren. Eine statistische Analyse der dysplastischen Nävi erbrachte eine höchst signifikante Differenz zwischen Patienten des gesetzlichen Screenings (54,2 Jahre) und Patienten unter 35 Jahren (23,4 Jahre). Die jüngere Patientengruppe (< 35 Jahre) wies fast doppelt so häufig histologisch nachgewiesene dysplastische Nävi als die Patienten des gesetzlichen Screenings (> 35 Jahre) auf. Dies könnte ein früheres Screening ab 20 Jahren befürworten, um mögliche Risikogruppen rechtzeitig zu identifizieren. Die Senkung der Melanommortalität als einziger Erfolgsparameter ist allerdings kritisch zu hinterfragen.
Diffus großzelliges B-Zell-Lymphom
Authors: Braitmaier Helmine
Published: November 2021

Das diffus großzellige B-Zell-Lymphom (DLBCL) ist eine aggressive Erkrankung, die unbehandelt schnell zum Tod führt. Mittlerweile können 60–70 % der Patienten mit Immunchemotherapien geheilt werden. Für theapieresistente Patienten oder für Patienten mit einem Krankheitsrückfall sind die Therapieoptionen begrenzt. Das könnte sich mit neuen Immuntherapien in der Entwicklung bald ändern, stellte Prof. Peter Borchmann, Köln, auf dem 9. Sommersymposium „Lymphome & Leukämien“ 2021 der Universitätsklinik Köln fest.
Der Stellenwert der subtotalen Petrosektomie im Rahmen der Cochlea Implantation
Authors: Issing Peter Rolf , Atanasova-Koch Srebrena , Schneider Jessica , Issing Christian
Published: November 2021

Einleitung Die Versorgung von Patienten mit chronischer Mittelohrentzündung oder vorliegender Radikalhöhle mit einem Cochlea-Implantat (CI) ist eine besondere Herausforderung. Die subtotale Petrosektomie (STP) stellt eine Möglichkeit dar, das Vorgehen sicherer zu machen.

Material und Methoden Es handelt sich um eine retrospektive Untersuchung von Patienten, die vor ihrer CI-Versorgung eine STP erhalten haben.

Ergebnisse Es wurden 25 Patienten eingeschlossen, bei denen insgesamt 26-mal meist 2-zeitig eine STP in der Regel etwa 6 Monate vor der CI-Operation erfolgte. Die Mehrheit der Patienten hatte eine chronische Mittelohrentzündung oder eine vorbestehende Radikalhöhle; bei einem Patienten zwang eine komplexe Felsenbeinfraktur mit Zerstörung des äußeren Gehörgangs zu dieser Methode. Nach der STP beobachteten wir 3-mal eine Wundheilungsstörung am Verschluss des äußeren Gehörgangs sowie eine Nachblutung an der Entnahmestelle des Bauchfetts in 2 Fällen. Alle Patienten konnten implantiert werden. Ein Rezidvcholesteatom ist bislang nicht aufgetreten.

Schlussfolgerung Mit dieser Vorgehensweise ist eine CI-Versorgung auch bei simultan bestehender Otitis media chronica oder vorliegender Radikalhöhle möglich. Wir favorisieren ein 2-zeitiges Vorgehen, wobei eine simultane STP und CI-OP auch vertretbar ist.