Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Introduction
Particle therapy emerged as a principal innovative technology for tumor treatment. However, it requires verification to exploit its full potential. Various approaches based on prompt gamma radiation were developed for range verification. Prompt gamma-ray timing (PGT), which determines the range of the therapeutic particles from time distributions of produced secondary gamma-rays, is a promising candidate for this as it is collimator-free and can be easily integrated into existing clinical beam deliveries [1]. However, phase instabilities between the accelerating radio frequency (RF) and the actual proton arrival time make phase monitoring indispensable [2]. In recent years, different concepts for proton bunch monitors (PBM) were developed [3,4]. The two most promising candidates are presented here.

Materials and Methods
A diamond detector with high radiation hardness and excellent time resolution was positioned close to the beam degrader. Protons scattered there were used to determine the phase correlation between RF and proton arrival time under realistic clinical conditions. The second monitor is a direct phasing tap on the low-level RF module of the IBA Proteus®C230 isochronous cyclotron. The correlation of both PBMs to the actual phase was checked in a scattering setup where protons from a pencil beam scattered in a thin polythene foil and then were coincidentally detected by CeBr₃-scintillators. The kinematics of this reaction makes the determination of the proton arrival time independent of the beam's bunch time spread.

Results
Both PBMs strongly correlate with the phase shift between the arrival time of the proton bunch and the RF. A model based on an over-damped, harmonic oscillator was able to describe the time-dependent change in the phase position and its correction by a control circuit with sufficient accuracy. Thus, the phase instabilities in the PGT data could be successfully corrected, enabling the improved measurement accuracy.

Summary
The phase instability of the proton bunch is the source of the greatest uncertainty of the PGT method [2]. Two PBMs were studied to correct these instabilities. PBM(s) complement the measurement setup, which should increase the sensitivity of the method and facilitate the translation of the PGT approach into clinical application.

Literature
[1] C. Golnik et al.: Range assessment in particle therapy based on prompt γ-ray timing measurements, Phys. Med. Biol. 59 (2014) 5399.
[2] T. Werner et al.: Processing of prompt gamma-ray timing data for proton range measurements at a clinical beam delivery, Phys. Med. Biol. 64 (2019) 105023.
[3] F. Permatasari: Development of a Clinically Applicable Technique for Range Verification in Proton Therapy Based on the PGT Method, PhD thesis, TU Dresden, in preparation.
[4] R.-D. Werner: Charakterisierung eines schnellen Diamantdetektors als PBM für die Reichweiteverifikation in der Protonentherapie, Masterarbeit, Universität Halle-Wittenberg, 2021.

Although 2-phosphonobutane-1,2,4,-tricarboxylic acid, PBTC, has manifold industrial applications, relevant and reliable data on the protonation of PBTC are poor. However, these data are critical parameters for ascertaining PBTC speciation, especially with regard to a sound structural and thermodynamic characterization of its metal ion complexes. A rigorous evaluation of pH-dependent 1H, 13C, and 31P chemical shifts along with accessible scalar spin–spin coupling constants (J) was performed in order to determine the pKa values of PBTC in 0.5 molal NaCl aqueous solution by means of nuclear magnetic resonance (NMR) spectroscopy. The phosphonate group revealed pKa values of 0.90 ± 0.02 and 9.79 ± 0.02, and the pKa values associated with the carboxylic groups are 3.92 ± 0.02, 4.76 ± 0.03, and 6.13 ± 0.03. Supported by DFT-calculated structures revealing strong intramolecular hydrogen bonding, the sequence of deprotonation could be unambiguously determined.

Presentations from the Workshop on Metadata Catalogues, which took place virtually via Zoom on the 4th April 2022. Rodare was presented to introduce a data publication repository in contrast to the metadata catalogues SciCAT and ICAT. A recording of the event can be found on the ExPaNDS website: https://expands.eu/presentations/

This paper proposes a new approach to relate the effective thermal conductivity of open-cell solid foams to their porosity. It is based on a recently published approach for estimating the dielectric permittivity of isotropic porous media. A comprehensive assessment was performed comparing the proposed mixing relation with published experimental data for thermal conductivity and with numerical data from state-of-the-art relations. The mixing relation for the estimation of thermal conductivities based on dodecahedrons as building blocks shows good agreement with experimental data over a wide range of porosity.

Superconducting niobium nitride (NbN) films with nominal thicknesses of 4 nm, 5 nm, 7 nm, and 9 nm were grown on
sapphire substrates using atomic layer deposition (ALD). We observed probed Hall resistance (HR) (Rxy) in external out-ofplane magnetic fields up to 6 T and magnetore-sistance (MR) (Rxx) in external in-plane and out-of-plane magnetic fields up
to 6 T on NbN thin films in Van der Pauw geometry. We also observed that positive MR dominated. Our study focused on the
analysis of interaction and localisation effects on electronic disorder in NbN in the normal state in temperatures that ranged
from 50 K down to the superconducting transition temperature. By modelling the temperature and magnetic field
dependence of the MR data, we extracted the temperature-dependent Coulomb interaction constants, spin–orbit scattering
lengths, localisation lengths, and valley degeneracy factors. The MR model allowed us to distinguish between interaction
effects (positive MR) and localisation effects (negative MR) for in-plane and out-of-plane magnetic fields. We showed that
anisotropic dephasing scattering due to lattice non-idealities in NbN could be neglected in the ALD-grown NbN thin films.

Focused Ion Beam (FIB) processing has been established as a well-suited and promising technique in R&D in nearly all fields of nanotechnology for patterning and prototyping on the μm-scale and below. Liquid Metal Alloy Ion Sources (LMAIS) represent an alternative to expand the FIB application fields beside all other source concepts. Here we present in the frame of two industrial related projects (ZIM) the development of different special LMAIS for FIB applications in nano–technology. So among others the alloys CoNd, CoNdB, AuGeB, AuGeBNi, AuSiCr, GaBiLi, CoDy, CuDy and AuSiDy are investigated and tested with regard to their use in modern mass separated FIB systems due to mass resolution, ion beam current of the certain ion species and the available spot size. The light ions like B, Li or Si dedicated for ion beam lithography systems. The transition metal elements Co, Fe and Ni are important for the modification and the adjustment of magnetic properties of nanomagnetic structures, presented in detail with a Co – FIB on a permalloy nanowire. Rare earth elements, especially Dy can tune the magnetic damping in nanometric dimensions. The latter is shown on magnonic stripe pattern of one mm² in size on a thin permalloy film made by a VELION FIB.

After more than a century applying flotation to the mining industry, two completely different strategies have been introduced for processing purposes. One is the classical approach viz. grinding ores to a certain extent (fine particles) and floating them via conventional mechanical and pneumatic cells i.e., Jameson, Imhoflot™ and Reflux™. This strategy continues because mines face declining cut-off grades, complex and poly-mineralized ores, and they are required to achieve an acceptable degree of mineral liberation. The other school of thought deals with coarse particle processes mainly owing to the low energy requirements, that includes SkimAir® flash, fluidized bed and HydroFloat™ cells. There is no study in the literature to comparatively present the recent developments of flotation apparatuses versus the conventional mechanical cells. To cover this knowledge gap in the literature, the present paper endeavors to critically evaluate these concepts from several points of view, including existing technological advancements, water and energy usage, kinetics, and circuit design. A brief introduction of advanced technologies, along with their applications is presented. The data from literature and case studies showed that the Jameson, Imhoflot™ and recently developed Reflux™ flotation cells can be very effective for recovering fine particles owing to their specific hydrodynamic designs, intensive energy dissipation rate and generation of micron-sized bubbles (100–700 μm). Very low (less than a few minutes) mean particle residence time, high gas-hold up (ca. 50–70 %), no agitation and high efficiency of particle-bubble collision were identified as their main advantages compared to traditional mechanical flotation cells. In addition to their common applications in cleaner stage, these cells were used in pre-flotation and scalping (producing final concentrate from the rougher feed) duties. Their main challenges were recognized as relatively unclear procedure on their scale up/down, optimization and simulation. The HydroFloat™ cell was indicated as a promising technology for recovering coarse particle fraction sizes by taking advantage of the fluidized-bed concept with plug-flow dispersion regime, high particle residence time, and limited cell turbulence. We finally concluded that fine particle flotation may remain as the main focus of re-processing tailings dams, while coarse particle treatment should be the focus of this century to reduce total energy consumptions.

Teaching "Programming with Python" for the workshop.
Workshop recordings are available on .

Noble metals in form of bulk materials are rarely used as catalysts in industrial applications due to their price and limited accessibility. However, the surface of commonly-used materials can be modified with an exceptionally low amount of platinoids to enhance their electrochemical activity. In this work, the surface of the free-standing nanoconical Ni structures was modified with a thin metallic rhodium layer with a spontaneous galvanic displacement process. It emerged that Rh-decorated Ni nanoconical electrodes exhibited higher catalytic activity in a model hydrogen evolution reaction in an alkaline environment in comparison to the unmodified electrode. Furthermore, the proposed synthesis protocol is high-speed and straightforward, making it promising in application on a semi and industrial scale. Linear Sweep Voltammetry measurements were used to test the catalytic activity in 1 M NaOH electrolyte. The nanoconical structures were highly-hydrophobic, what has been observed by dedicated camera-based equipment. In addition, the electrochemically-active surface area (ECSA) of tested electrodes were estimated and confirmed in atomic force microscope AFM measurements. The durability of coatings was tasted in 1 M NaOH for 14 days.

We present EZ, a novel Current Deposition algorithm for particle-in-cell simulations, which calculates the current density field due to macro-particle motion within a time step by solving the electrodynamic continuity equation.
Being a charge conserving hybridization of \textbf{E}sirkepov's method and \textbf{Z}igZag, we refer to it as ``EZ'' as shorthand for ``Esirkepov meets ZigZag''.
EZ achieves the same level of charge conservation as the commonly used method by Esirkepov, yet reaches higher performance for macro-particle assignment-functions up to third-order.
Key considerations of its implementation in PIConGPU, an open source, C++, performance portable, fully relativistic 3D3V particle-in-cell code, are outlined in addition to the detailed description of EZ along with remarks on its optimization and customization.

The results of the analysis of the accuracy of the commonly used ground-state exchange-correlation (XC) functionals (LDA, PBE, PBEsol, AM05, SCAN) at warm dense matter conditions are presented [1,2]. We considered both unpolarized and polarized electrons. The analysis is performed by comparing to the available path-integral quantum Monte-Carlo (QMC) data. The relative deviation of the total density from the reference data is reported for different XC functionals in the case of the inhomogeneous electron gas. As a key finding of our evaluation, we emphasize that the overall performance of the ground-state XC functionals worsens with increasing the wavenumber of density perturbation.
Finally, the non-linear static density response of electrons is investigated using KS-DFT approach [3]. The results are verified by comparing to the QMC data when thermal temperature is equal to the Fermi temperature. New results for partially and strongly degenerate electrons are presented.

REFERENCES

[1] Z. Moldabekov, T.Dornheim, M. Böhme, J. Vorberger, A. Cangi, The relevance of electronic perturbations in the warm dense electron gas. The Journal of Chemical Physics 155, 124116 (2021).
[2] Z. Moldabekov, T.Dornheim, J. Vorberger, A. Cangi, Benchmarking Exchange-Correlation Functionals in the Spin-Polarized Inhomogeneous Electron Gas under Warm Dense Conditions. Physical Review B, accepted for publication (2022), arXiv:2110.06708 .
[3] Z.Moldabekov, T. Dornheim, J. Vorberger, Density-Functional-Theory Perspective on the Non-Linear Response of Correlated Electrons Across Temperature Regimes, arXiv:2201.01623 (2022)

The enzymatic hydrolysis of sunflower oil occurs at the water–oil interface. Therefore, the characterization of dynamic interfacial phenomena is essential for understanding the related mechanisms for process optimizations. Most of the available studies for this purpose deal with averaged interfacial properties determined via reaction kinetics and dynamic surface tension measurements. In addition to the classical approach for dynamic surface tension measurements, here, the evolution of the dilational viscoelasticity of the lipase adsorbed layer at the water–oil interface is characterized using profile analysis tensiometry. It is observed that lipase exhibits nonlinear dilational rheology depending on the concentration and age of the adsorbed layer. For reactive water–oil interfaces, the response of the interfacial tension to the sinusoidal area perturbations becomes more asymmetric with time. Surface-active products of the enzymatic hydrolysis of triglycerides render the interface less elastic during compression compared to the expansion path. The lipolysis products can facilitate desorption upon compression while inhibiting adsorption upon expansion of the interface. Lissajous plots provide an insight into how the hysteresis effect leads to different interfacial tensions along the expansion and compression routes. Also, the droplet shape increasingly deviates from a Laplacian shape, demonstrating an irreversible film formation during aging and ongoing hydrolysis reaction, which supports our findings via interfacial elasticity analysis.

Lithium-Ion batteries (LIBs) are an important pillar for the sustainable transition of the mobility and energy storage sector. LIBs are complex devices for which waste management must incorporate different recycling technologies to produce high-quality secondary (raw) materials at high recycling efficiencies (RE). This contribution on LIB recycling investigated the influence of different pretreatment strategies on the subsequent processing. The experimental study combined different dismantling depths and depollution temperatures with subsequent crushing and thermal drying. Therein, the removal of organic solvent is quantified during liberation and separation. This allows to evaluate the safety of cell opening according to the initial depollution status. These process steps play a key role in the recycling of LIBs when using the low temperature route. Therefore, combinations of pretreatment and processing steps regarding technical and economic feasibility are discussed. Moreover, the process medium and equipment properties for a safe cell opening, the technical recycling efficiencies and their consequences on future industrial LIB waste management are pointed out.

We measured 135 cross sections of residual nuclei produced in fragmentation reactions of 12C, 14N, and 13−16,20,22O projectiles impinging on a carbon target at kinetic energies of near 400A MeV, most of them for the first time, with the R 3B/LAND setup at the GSI facility in Darmstadt (Germany). The use of this state-of-the-art experimental setup in combination with the inverse kinematics technique gave the full identification in atomic and mass numbers of fragmentation residues with a high precision. The cross sections of these residues were determined with uncertainties below 20% for most of the cases. These data are compared to other previous measurements with stable isotopes and are also used to benchmark different model calculations.

Presentation a 2022 DPG spring meeting (section "Hadrons & Nuclei"), March 31, 2022

In recent years, scientists have progressively recognized the role of electronic structure in the characterization of chemical and physical properties for actinide containing materials. High-energy resolution X-ray spectroscopy at the actinide M4,5 edges emerged as a promising direction because this method can probe actinide properties at the atomic level through the possibility of reducing the experimental spectral width below the natural core-hole life time broaden-ing.

In this lecture, I will describe the latest progress in the field of high-energy resolution X-ray spectroscopy at the acti-nide M4,5 edges1. More than 10 years passed after the first X-ray spectroscopy experiment in the high-energy resolu-tion mode on uranium systems at the U M4 edge (~3728 eV) in 20092. Quite a bit is known for the moment and X-ray absorption spectroscopy (XAS) or X-ray absorption near edge structure (XANES) in the high-energy resolution fluo-rescence detection (HERFD) mode together with resonant inelastic X-ray scattering (RIXS) or resonant X-ray emission spectroscopy (RXES) are now common techniques for studying the physics and chemistry of the f-block elements. I will show that the methods are able to a) provide fingerprint information on the actinide oxidation state and ground state character b) probe 5f occupancy, non-stoichiometry, defects c) investigate the local symmetry and effects of the crystal field3–12

Understanding the electronic transport properties of materials under high temperatures and pressures is essential for constraining geophysical processes and provides indispensable insights useful for novel materials discovery. The difficulty of measuring the electrical conductivity of iron under Earth-core conditions reliably in experiments calls for sophisticated theoretical methods that can support diagnostics. We present results of the electrical conductivity in iron within the pressure and temperature ranges found in Earth's core by simulating microscopic Ohm's law using time-dependent density functional theory. Our predictions are independent of previous studies, which primarily used the Kubo-Greenwood formula, and therefore provide a new perspective on resolving discrepancies in recent experiments.

Time-dependent density functional theory (TDDFT) enables calculating electronic transport properties in the warm dense matter (WDM) and is an alternative to present state-of-the-art approaches. In the real-time formalism of TDDFT (RT-TDDFT), the electrical conductivity is directly computed from the time evolution of the electronic current density and provides direct means to assess the validity of Ohm's law in WDM. Without relying on the methods of diagonalization, the method is computationally fast compared to linear-response TDDFT (LR-TDDFT). We present TDDFT calculations of the electrical conductivity in iron within the pressure and temperature ranges found in Earth's core and discuss the ramifications of using TDDFT for calculating the electrical conductivity in contrast to the Kubo-Greenwood (KG) formalism and dielectric models.

Störungen in der Regulation der Expression von Genen in Zellen sind von großer Bedeutung für die Entstehung von Krebserkrankungen. Die Transkription von Genen wird u. a. durch den Grad der Acetylierung von bestimmten DNA-bindenden Proteinen, den Histonen, reguliert. Damit kommt den Histondeacetylasen (HDACs), die enzymatisch Acetylgruppen u. a. von Histonmolekülen abspalten, eine besondere Bedeutung bei der transkriptionellen Regulation von tumorrelevanten Genen, wie bspw. Tumorsuppressorgenen, zu. HDAC-Inhibitoren werden daher als aussichtsreiche Medikamente für die Krebstherapie untersucht. Mit Hilfe des nicht-invasiven Bildgebungsverfahrens Positronen-Emissions-Tomographie könnte es möglich sein, die Rolle von einzelnen Histondeacetylasen für die Entstehung und Progression neuroonkologischer Erkrankungen, wie bspw. Gliome, zu untersuchen.
Das Ziel dieser Arbeit ist es, neuartige hochpotente, spezifische und fluorhaltige Inhibitoren für die besonders tumorrelevanten Histondeacetylasen HDACs1/2 auf der Grundlage der Leitstrukturen BRD8951, Cpd-60 und Cpd-4 zu entwickeln. Nach der pharmakologischen Charakterisierung der HDAC-Inhibitoren gegenüber humaner, rekombinanter HDAC1/2 und der Bestimmung der Spezifität gegenüber humaner HDAC3 und HDAC6, wurde die potente und HDAC1/2-spezifische Verbindung N-[2-Amino-5-(thiophen-3-yl)phenyl]-4-[(2-fluorpropanamido)methyl]benzamid (BA3) ausgewählt und als Radiotracer weiterentwickelt. Durch die Herstellung eines geeigneten Präkursors wurde das Radionuklid Fluor-18 durch eine nukleophile Substitution eingeführt und der entsprechende Radioligand [18F]BA3 generiert. Anschließend wurde eine automatisierte Radiosynthese entwickelt. Erste biologische Experimente in der Maus zeigten jedoch, dass der Radiotracer eine geringe Hirnaufnahme aufweist, die u. a. auf die Interaktion mit P-Glykoprotein als Effluxtransporter zurückzuführen ist. Zusätzlich wurde ein hoher Anteil radioaktiver Metabolite im Hirn 30 min p.i. nachgewiesen, sodass das detektierte radioaktive Signal nicht allein dem Radioliganden [18F]BA3 zugeordnet werden kann. Die erhaltenen Daten sprechen gegen eine Verwendung dieses Radiotracers in der In-Vivo-Bildgebung der HDACs1/2. Daraufhin sollten die vermutlich metabolisch stabileren HDAC-Inhibitoren N-[2-Amino-5-(thiophen-2-yl)phenyl]-4-[(3-fluor-2,2-dimethylpropanamido)-methyl]benzamid (BA15) und N-(4-Amino-4'-fluor-[1,1'-biphenyl]-3-yl)-4-(pivalamidomethyl)-benzamid (BA17) radiofluoriert werden. Unabhängig von den In-vivo-Untersuchungen wurde das toxikologische Potential von BA3, BA15 und BA17 gegenüber ausgewählten Tumorzelllinien untersucht. Die HDAC-Liganden weisen eine vergleichbare Toxizität gegenüber etablierten HDAC-Inhibitoren auf.

Einleitung

Aufgrund der steilen Dosisgradienten und der Variabilität des Bremsvermögens kann die Präzision der Protonentherapie durch Bewegungen und anatomische Veränderungen stark kompromittiert werden. Hieraus resultiert ein hoher Bedarf für eine Online-Verifizierung der Behandlung. Als leichtes, kollimatorfreies System, das einfach in bestehende Anlagen integriert werden kann, ist die Prompt Gamma-Ray Timing (PGT) Methode eine vielversprechende Kandidatin für diese Anwendung. Die Entwicklung eines solchen Systems stellt jedoch eine Herausforderung dar, da die im Patienten applizierte Protonenreichweite mit hoher Genauigkeit aus der zeitlichen Verteilung einer limitierten Anzahl von Gammaquanten rekonstruiert werden muss. Bisher basierte diese Rekonstruktion auf dem arithmetischen Mittel und der Standardabweichung der Verteilung, aber die Genauigkeit dieser Methode erwies sich als begrenzt. Ziel dieser Studie war deshalb die Entwicklung multivariater statistischer Modelle auf Basis weiterer Histogramm-Merkmale und somit eine Optimierung der Verifikationsgenauigkeit der PGT-Methode.

Material & Methoden

Es wurden PGT-Verteilungen analysiert, die während einer statischen Pencil-Beam-Bestrahlung eines Acrylglasphantoms mit unterschiedlich dicken Lufthohlräumen aufgenommen wurden. Relevante Histogramm-Merkmale wurden aus den Empfehlungen der Image Biomarker Standardisation Initiative abgeleitet und automatisiert mittels Vorwärtsauswahl (Forward Selection) sowie der Least Absolute Shrinkage and Selection Operator (LASSO) Methode ausgewählt. Diese Merkmale wurden anschließend in multivariaten linearen Regressionsmodellen genutzt um die Hohlraumdicke vorherzusagen. Die Güte der Modelle wurde anhand ihres Bestimmtheitsmaßes R2 und ihres mittleren quadratischen Fehlers RMSE an einem unabhängigen Datensatz bewertet. Abschließend wurde ein homogenes Bestrahlungsfeld im Pencil-Beam-Scanning-Verfahren appliziert und die Modellvorhersage anhand von zweidimensionaler Bildgebung verglichen.

Ergebnisse

Die neu entwickelten Modelle zeigen eine stark verbesserte Vorhersagekraft (R2 > 0,6) im Vergleich zur bisherigen Methodik (R2 < 0,1, s. Abbildung 1). Beide Selektionsmethoden erreichen eine ähnliche Vorhersagekraft. Die Modelle erzielen ihre maximale Vorhersagekraft ab etwa vier kombinierten Histogramm-Merkmalen, wobei sich insbesondere die robuste mittlere Abweichung und die Kurtosis als starke Prädiktoren erweisen. Die neu entwickelten Modelle ermöglichen die Identifizierung der eingebrachten Lufthohlräume im gescannten Bestrahlungsfeld (Abbildung 2).

Diskussion

Diese Ergebnisse zeigen, dass die statistische Modellierung ein wertvolles Instrument zur Optimierung der Prompt Gamma-Ray Timing Methode ist und demonstrieren ihr Potential zur Anwendung für die Behandlungsverifikation der Protonentherapie.

We report a change in the structural and magnetic properties of epitaxial Mn5Ge3 on a Ge-on-Si (111) substrate by applying strain engineering through ms-range flash lamp annealing (FLA). X-ray diffraction results demonstrate that during FLA for 20 ms, the formation of nonmagnetic MnxGey secondary phases is suppressed, while the in-plane expansion of the lattice increases with increasing annealing temperature. Temperature-dependent magnetization results indicate that the Curie temperature of Mn5Ge3 rises from 287 K in the as-prepared sample to above 400 K after FLA, making Mn5Ge3 an attractive material for spintronics. Experimental results together with theoretical Monte Carlo simulations allow us to conclude that the expansion of the in-plane lattice causes the increase of the Curie temperature due to enhancement of the ferromagnetic interaction between Mn atoms.

Due to the lack of appropriate tailoring of the inter-connection weights, the segmentation performance of the recently suggested Quantum-inspired Self-supervised Neural Network models suffers from the slow convergence problem. As a result, using quantum-inspired meta-heuristics in Quantum-Inspired Self-supervised Neural Network models improves their hyper-parameters and inter-connection weights. The goal of this paper is to propose an improved version of a Quantum-Inspired Self-supervised Neural Network (QIS-Net) model for brain lesion segmentation. The proposed Optimized Quantum-Inspired Self-supervised Neural Network (Opti-QISNet) model is based on the QIS-Net architecture, and its operations are used to get the best segmentation results. A Quantum-Inspired Optimized Multi-Level Sigmoidal (Opti-QSig) activation is the optimized activation function used in the described model. Three quantum-inspired meta-heuristics improve the Opti-QSig activation function, with fitness evaluated using Otsu’s multi-level thresholding. Experiments were carried out using brain MR images from the Cancer Imaging Archive (TCIA) in the Nature data repository. The results show that the proposed self-supervised Opti-QISNet model outperforms our recently established QIBDS Net and QIS-Net models in brain lesion segmentation, and it is a potential candidate to extensively supervised neural network based architectures (UNet and FCNNs).

An observation of Charged Lepton Flavor Violation (CLFV) would be unambiguous evidence for
physics beyond the Standard Model. The Mu2e and COMET experiments, under construction, are
designed to push the sensitivity to CLFV in the μ → e conversion process to unprecedented levels.
Whether conversion is observed or not, there is a strong case to be made for further improving
sensitivity, or for examining the process on additional target materials. Mu2e-II is a proposed
upgrade to Mu2e, with at least an additional order of magnitude in sensitivity to the conversion
rate over Mu2e. The approach and challenges for this proposal are summarized. Mu2e-II may be
regarded as the next logical step in a continued high-intensity muon program at FNAL.

Recent major advances in Accelerator Mass Spectrometry (AMS) at the Vienna Environmental Research Accelerator (VERA) regarding detection efficiency and isobar suppression have opened possibilities for the analysis of additional long-lived radionuclides at ultra-low environmental concentrations. These radionuclides, including 233U, 135Cs, 99Tc, and 90Sr, will become important for oceanographic tracer application due to their generally conservative behavior in ocean water. In particular, the isotope ratios 233U/236U and 137Cs/135Cs have proven to be powerful fingerprints for emission source identification as they are not affected by elemental fractionation. Improved detection efficiencies allowed us to analyze all major long-lived actinides, i.e., 236U, 237Np, 239,240Pu, 241Am as well as the very rare 233U, in the same 10 L water samples of a depth profile from the northwest Pacific Ocean. For this purpose, a simplified and very flexible chemical purification procedure based on extraction chromatography (a single UTEVA® column) was implemented which can be extended by a DGA® column for Am purification. The procedure was validated with the reference materials IAEA-381/385. With the additional increase in ionization efficiency expected for the extraction of actinides as fluoride molecules from the AMS ion source, a further reduction of chemical processing may become possible. This method was successfully applied to an exemplary set of air filter samples. In order to determine the quantitative 237Np concentration reliably, a 236Np spike material is being developed in collaboration with the University of Tsukuba, Japan. Ion-Laser Interaction Mass Spectrometry (ILIAMS), a novel technique for the efficient suppression of stable isobaric background, has been developed at VERA and provides unprecedented detection sensitivity for the fission fragments 135Cs, 99Tc, and 90Sr. The corresponding setup is fully operational now and the isobar suppression factors of >105 achieved, in principle, allow for the detection of the mentioned radionuclides in the environment. Especially for 90Sr analysis, this new approach has already been validated for selected reference materials (e.g., IAEA-A-12) and is ready for application in oceanographic studies. We estimate that a sample volume of only (1–3) L ocean water is sufficient for 90Sr as well as for 135Cs analysis, respectively.

To satisfy the principles of FAIR software, software sustainability and software citation, research software must be formally published. Publication repositories make this possible and provide published software versions with unique and persistent identifiers. However, software publication is still a tedious, mostly manual process. To streamline software publication, HERMES, a project funded by the Helmholtz Metadata Collaboration, develops automated workflows to publish research software with rich metadata.
This talk presents the progress of the first year and summarises the interaction with the Helmholtz Association and beyond.

Actinide coordination chemistry has attracted chemists´ interest for decades in terms of nuclear safety, catalysis, or radiopharmaceutical research. Especially the early actinides exhibit an unusually large range of oxidation states, which originates in the near degeneracy of the 5f, 6d and 7s energy levels. This offers unique chemical and physical properties, not yet fully understood. Schiff bases like the mixed N, O donor ligands of the salen (Bis(salicyliden)ethylendiamine) family are frequently chosen systems for complexation studies, because of their advantageous ability to stabilize a large number of metals including actinides, as well as their tuneable electronical and sterical properties. Based on pyrrole structural relatives of salen can be constructed, which only exhibit N-donor functionalities. This provides the possibility to investigate and compare the binding situation between early actinides and N atoms in different environments.
In this study a complex series with Th and U as well as the transuranic elements Np and Pu with the pyrrole-based ligand 1,2-ethylenediamine-N,N’-bis(1H-pyrrol-2-yl)methylene (H2pyren) H2L1 was synthesized. Characterization in solid state (via SC-XRD) shows an 8-fold coordination at the metal centre, where all N donors participate. Moreover, the An−Npyrrolide bond distance is in all cases shorter, compared to the An−Nimine bond. Quantum chemical calculations, including Pa(IV) prove not only the bond shortening, but also an increased bond strength for An−Npyrrolide over An−Nimine. Comparison to the salen system shows preference of the mixed N,O donor ligand over its pure N,N donor relative for Th as well as U-Pu. For Pa, however, the pyren ligand is preferred over salen, pointing to a special role of the f 1 electron configuration in actinide(IV) coordination chemistry. Synthesis of a mixed pyren salen complex shows a significant expansion of the 1H NMR shift range and altered signal position compared to the bis complexes. This indicates a possible reorientation of the easy axis of magnetization upon ligand exchange. Further investigations on the influence of ligand substitution is achived by synthesis of the mono pyren complex [UCl2(py)(pyren)] and comparison to the analogous salen complex.

Cancer stem cells (CSCs) are a major cause of tumor therapy failure. This is mainly attributed to increased DNA repair capacity and immune escape. Recent studies have shown that functional DNA repair via homologous recombination (HR) prevents radiation-induced accumulation of DNA in the cytoplasm, thereby inhibiting the intracellular immune response. However, it is unclear whether CSCs can suppress radiation-induced cytoplasmic dsDNA formation. Here, we show that the increased radioresistance of ALDH1-positive breast cancer stem cells (BCSCs) in S phase is mediated by both enhanced DNA double-strand break repair and improved replication fork protection due to HR. Both HR-mediated processes lead to suppression of radiation-induced replication stress and consequently reduction of cytoplasmic dsDNA. The amount of cytoplasmic dsDNA correlated significantly with BCSC content (p=0.0002). This clearly indicates that HR-dependent avoidance of radiation-induced replication stress mediates radioresistance and contributes to its immune evasion. Consistent with this, enhancement of replication stress by inhibition of ataxia telangiectasia and RAD3 related (ATR) resulted in significant radiosensitization (SER37 increase 1.7-2.8 Gy, p<0.0001). Therefore, disruption of HR-mediated processes, particularly in replication, opens a CSC-specific radiosensitization option by enhancing their intracellular immune response.

The mean ionization state (MIS) is a critical property in dense plasma and warm dense matter research. It is used (for example) as an input parameter in various models, including for example the calculation of adiabats in inertial confinement fusion; it is also used to help interpret and fit experimental results. Unfortunately however, theoretical predictions of the MIS are often inconsistent with each other and experimental data. In this presentation, I will compute the MIS using a variety of approaches in an average-atom model and compare results with higher-fidelity simulations and experimental benchmarks [1]. I will show that the canonical approach for computing the MIS is usually insufficient; I will also discuss a novel approach based on the electron localization function, which yields improved results but tends to systematically under-estimate the MIS. Finally, I will adapt a recently-proposed Kubo–Greenwood method [2] to our computationally efficient average-atom model, which shows very promising agreement with all the benchmarks considered, with one example shown in Fig. 1 below.

[1] Callow, Kraisler and Cangi, arXiv:2203.05863 (2022)
[2] Bethkenhagen et al., Phys. Rev. Research 2, 023260 (2020)

During the COVID-19 pandemic, many organizations (e.g. businesses, companies, government facilities, etc.) have attempted to reduce infection risk by employing partial home office strategies. However, working from home can also reduce productivity for certain types of work and particular employees. Over the long term, many organizations therefore face a need to balance infection risk against productivity. Motivated by this trade-off, we model this situation as a bi-objective optimization problem and propose a practical approach to find trade-off (Pareto optimal) solutions. We present a new probabilistic framework to compute the expected number of infected employees as a function of key parameters including: the incidence level in the neighborhood of the organization, the COVID-19 transmission rate, the number of employees, the percentage of vaccinated employees, the testing frequency, and the contact rate among employees.We implement the model and the optimization algorithm and perform several numerical experiments with different parameter settings. Furthermore, we provide an online application based on the models and algorithms developed in this paper, which can be used to identify the optimal workplace occupancy rate for real-world organizations.

Ultrafast demagnetization in diverse materials has sparked immense research activities due to its captivating richness and contested underlying mechanisms. Among these, the two most celebrated mechanisms have been the spin-flip scattering (SFS) and spin transport (ST) of optically excited carriers. In this work, we have investigated femtosecond laser-induced ultrafast demagnetization in perpendicular magnetic anisotropy-based synthetic antiferromagnets (p-SAFs) where [Co/Pt]n−1/Co multilayer blocks are separated by Ru or Ir spacers. Our investigation conclusively shows that the ST of optically excited carriers can have a significant contribution to the ultrafast demagnetization in addition to SFS processes. Moreover, we have also achieved an active control over the individual mechanisms by specially designing the SAF samples and altering the external magnetic field and excitation fluence. Our study provides a vital understanding of the underlying mechanism of ultrafast demagnetization in synthetic antiferromagnets, which will be crucial in future research and applications of antiferromagnetic spintronics.

Ever since its discovery ultrafast demagnetization has remained one of the most
intriguing research areas in magnetism. Here, we demonstrate that in [Co (tCo )/
Pd (0.9 nm)] 8 multilayers, the characteristic decay time in femtosecond time-
scale varies non-monotonically with tCo in the range 0.07 nm B tCo B 0.75 nm.
Further investigation reveals higher spin fluctuation at higher ratio of electron to
Curie temperature to be responsible for this. Microscopic three-temperature
modelling unravels a similar trend in the spin–lattice interaction strength, which
strongly supports our experimental observation. The knowledge of the fem-
tosecond magnetization decay mechanism in ultrathin ferromagnetic films is
unique and important for the advancement of fundamental magnetism besides
their potential applications in ultrahigh speed spintronic devices.

In recent years, scientists have progressively recognized the role of electronic structure in the characterization of chemical and physical properties for actinide containing materials. High-energy resolution X-ray spectroscopy at the actinide M4,5 edges emerged as a promising direction because this method can probe actinide properties at the atomic level through the possibility of reducing the experimental spectral width below the natural core-hole life time broadening [1].

In this lecture, I will describe the latest progress in the field of high-energy resolution X-ray spectroscopy at the actinide M4,5 edges [2]. More than 10 years passed after the first X-ray spectroscopy experiment in the high-energy resolution mode on uranium systems at the U M4 edge (~3728 eV) [1] at ESRF in 2009 [3,4]. Quite a bit is known for the moment and X-ray absorption spectroscopy (XAS) or X-ray absorption near edge structure (XANES) in the high-energy resolution fluorescence detection (HERFD) mode (also known as HR-XANES) together with resonant inelastic X-ray scattering (RIXS) or resonant X-ray emission spectroscopy (RXES) are now common techniques for studying the physics and chemistry of the f-block elements [5]. I will show that the methods are able to a) provide fingerprint information on the actinide oxidation state and ground state character b) probe 5f occupancy, non-stoichiometry, defects c) investigate the local symmetry and effects of the crystal field [6–14].

Over the past several years, our understanding of plutonium chemistry at the atomic level was greatly improved. This is partly due to the expansion of advanced analytical techniques, developed at the large-scale synchrotron facilities, which recently become available for the investigation of radioactive materials. This contribution will give an overview of those experimental methods available at various synchrotrons and applicable to studying physico-chemical processes of radionuclides behaviour in the environment.

I will mainly focus on high energy resolution fluorescence detected (HERFD) X-ray absorption spectroscopy and Resonant Inelastic X-ray Scattering (RIXS) methods1, which probe the local and electronic structure of actinide materials at the L3 and M4 actinide absorption edges. HERFD and RIXS techniques have high sensitivity towards oxidation state detection and can provide unprecedented information on the ground state configuration, electron-electron interactions, and hybridization between molecular orbitals. I will show the results of recently performed studies on plutonium oxide nanoparticles2–5, which were achieved by the combination of HERFD, RIXS, EXAFS, XRD, HEXS (PDF) synchrotron methods together with results on thorium6,7 and uranium8 oxide nanoparticles. The experimental results were analyzed using electronic structure calculations 9,10. It might be of interest for fundamental research in chemistry and physics of actinides as well as for applied science.

In recent years, scientists have progressively recognized the role of electronic structure in the characterization of chemical and physical properties for actinide containing materials. High-energy resolution X-ray spectroscopy at the actinide M4,5 edges emerged as a promising direction because this method can probe actinide properties at the atomic level through the possibility of reducing the experimental spectral width below the natural core-hole life time broadening.

In this lecture, I will describe the latest progress in the field of high-energy resolution X-ray spectroscopy at the actinide M4,5 edges1. More than 10 years passed after the first X-ray spectroscopy experiment in the high-energy resolution mode on uranium systems at the U M4 edge (~3728 eV) in 20092–4. Quite a bit is known for the moment and X-ray absorption spectroscopy (XAS) or X-ray absorption near edge structure (XANES) in the high-energy resolution fluorescence detection (HERFD) mode together with resonant inelastic X-ray scattering (RIXS) or resonant X-ray emission spectroscopy (RXES) are now common techniques for studying the physics and chemistry of the f-block elements. I will show that the methods are able to a) provide fingerprint information on the actinide oxidation state and ground state character b) probe 5f occupancy, non-stoichiometry, defects c) investigate the local symmetry and effects of the crystal field5-15.

We study the charge and spin dependent scattering in a set of CoFeB thin films whose crystalline order is systematically enhanced and
controlled by annealing at increasingly higher temperatures. Terahertz conductivity measurements reveal that charge transport closely
follows the development of the crystalline phase, with the increasing structural order leading to higher conductivity. The terahertz-induced
ultrafast demagnetization, driven by spin-flip scattering mediated by the spin–orbit interaction, is measurable in the pristine amorphous sam-
ple and much reduced in the sample with the highest crystalline order. Surprisingly, the largest demagnetization is observed at intermediate
annealing temperatures, where the enhancement in spin-flip probability is not associated with an increased charge scattering. We are able to
correlate the demagnetization amplitude with the magnitude of the in-plane magnetic anisotropy, which we characterize independently, sug-
gesting a magnetoresistance-like description of the phenomenon.

Extending the potential window towards the 3V plateau below the typically used range could boost the effective capacity of LiMn2O4 spinel cathodes. . This usually leads to an “overdischarge” of the cathode, which can cause severe material damage due to manganese dissolution into the electrolyte and a critical volume expansion (induced by Jahn-Teller distortions). As those factors determine the stability and cycling lifetime for all-solid-state batteries, the operational window of LiMn2O4 is usually limited to 3.5 – 4.5 V vs. Li/Li+ in common battery cells. However, it has been reported that nano-shaped particles and thin films can potentially mitigate these detrimental effects. We report here that porous LiMn2O4 thin film cathodes with a certain level in off-stoichiometry show improved cycling stability for the extended cycling range of 2.0 – 4.5 V vs. Li/Li+. We argue through operando Spectroscopic Ellipsometry that the origin of this stability lies in the surprisingly small volume change in the layer during lithiation.

This contribution provides an overview of a current research network funded by the German Federal Ministry of Education and Research (BMBF), entitled “Fundamental investigations of actinide immobilization by incorporation into solid phases relevant for final disposal” – AcE. The AcE project aims at understanding the incorporation and immobilization of actinides (An) in crystalline, repository-relevant solid phases, such as zirconia (ZrO2) and UO2, but also in zircon (ZrSiO4), pyrochlores (Ln2Zr2O7) and orthophosphates of the monazite type (LnPO4), which may find use as host matrices for the immobilization and safe disposal of high-level waste streams.
The main objectives of the AcE project are (i) the development of synthesis strategies for An(IV)-doped solid phases, (ii) understanding their associated structural and physical properties using combined modelling and experimental approaches and (iii) determining their performance after irradiation with particular regard to an assessment of their long-term stability, dissolution behavior, and suitability for An matrix incorporation.

Recent results obtained for ZrO2, the main corrosion product of the Zircaloy cladding material surrounding nuclear fuel rods, will also be discussed. ZrO2 is monoclinic phase (P2(1)/c) at ambient conditions, and transforms into tetragonal (P4(2)/nmc) and cubic phases (Fm3 ̅m) at high temperatures of around 1200 °C and 2370 °C, respectively. However, particle size effects, the incorporation of foreign ions such as the actinides, as well as high radiation fields are known to also influence the stability fields of the polymorphs. A short overview of experimental studies conducted by the AcE partners, addressing both the ZrO2 bulk structure, irradiation-induced changes, as well as the An environment during and after such structural transformations, will be given.

We present the deliverables achieved for a summarization of the prototyped remote data analysis services and the derived outcomes that have been realised in the process at each ExPaNDS partner facility to align with the PanOSC project and to proceed towards onboarding services into the EOSC portal. The work represents the achievement of deliverable D4.4 of the Horizon 2020 ExPaNDS project. ExPaNDS is the EU Project: European Open Science Cloud Photon and Neutron Data Services

The incorporation of actinides in lanthanide phosphate matrices crystallizing in the monazite structure has been intensely investigated in the past decades due to the relevance of these monazites as potential ceramic host phases for the immobilization of specific high level radioactive waste (HLW) streams [1-3]. In recent years, understanding the incorporation behaviour of trivalent dopants in the LnPO4•xH2O rhabdophane structure has been given more attention [4,5]. Rhabdophane is the hydrated phosphate precursor in the synthesis of monazites through precipitation routes and a potential secondary mineral controlling actinide solubility in dissolution and re-precipitation reactions of monazite host-phases. Despite the large interest in lanthanide phosphates and the interaction of actinides with these solids, very little data [6-8] is available on the complexation of lanthanides and actinides with aqueous phosphates, even though these complexation reactions precede any aqueous synthesis of monazite ceramics and are expected to occur in natural waters as well as in the proximity of monazite-containing HLW repositories. In many cases, an independent spectroscopic validation of the stoichiometry of the proposed complexes, is also missing. Both from the perspective of aqueous rhabdophane synthesis, which is often carried out at elevated temperatures, and heat-generating HLW immobilization in monazites, the lanthanide and actinide complexation reactions with aqueous phosphates under ambient conditions should be complemented with data obtained at higher temperatures.

In the present work, laser-induced luminescence spectroscopy was used to study the complexation of Cm(III) (1.15×10−8 to 1.15×10−7 M) as a function of total phosphate concentration (0 to 0.08 M) in the temperature regime 25-90 °C, using NaClO4 as a background electrolyte (I = 0.5 to 3.0 M). These studies have been conducted in the acidic pH-range (−log10 [H+] = 1.00, 2.52, 3.44, and 3.65) to avoid precipitation of solid Cm rhabdophane. For the first time, in addition to the presence of CmH2PO42+ already evidenced before [6,7], the formation of Cm(H2PO4)2+ was unambiguously established from the luminescence spectroscopic data collected at the various H+ concentrations previously mentioned [8].
The conditional complexation constants of both aqueous complexes were found to increase upon rising ionic strength and temperature. Extrapolation of the obtained complexation constants to infinite dilution at 25 °C was performed by applying the Specific Ion Interaction Theory (SIT) [9]. The obtained log β° values for CmH2PO42+ and Cm(H2PO4)2+ were 0.45 ± 0.04 and 0.08 ± 0.07 [8], respectively, for reactions 1 and 2 below:

Cm3+ + H3PO4 ⇌ CmH2PO42+ + H+ (1)
Cm3+ + 2 H3PO4 ⇌ Cm(H2PO4)2+ + 2 H+ (2)

The ion interaction coefficients ε(CmH2PO42+;ClO4−) = 0.17 ± 0.04 and ε(Cm(H2PO4)2+;ClO4−) = −0.10 ± 0.06 were derived at 25 °C [8].

Temperature-dependent conditional complexation constants for the identified species were obtained from the recorded luminescence emission spectra. They were subsequently extrapolated to I =0 M, assuming that the ion interaction parameters obtained at 25 °C are not significantly impacted by the temperature increase from 25 °C to 90 °C [6]. Using the integrated van´t Hoff equation, both the molar enthalpy of reaction ΔrHm° and entropy of reaction ΔrSm° values were found to be positive for the two complexes, namely CmH2PO42+ and Cm(H2PO4)2+ [8].

Relativistic quantum chemical investigations revealed a monodentate binding of the H2PO4− ligand to the central Cm3+ ion to be the most stable configuration for both complexes. By combining ab initio calculations with a thorough analysis of the obtained luminescence spectroscopic data, both CmH2PO42+ and Cm(H2PO4)2+ complexes with an overall CN of 9 were shown to be stable in solution at 25 °C. However, a different temperature-dependent evolution of the coordination of the Cm3+ ion to hydration water molecules could be derived from the electronic structure of the Cm(III)-phosphate complexes. More specifically, an overall coordination number of 9 was retained for the CmH2PO42+ complex in the investigated temperature range (25 to 90 °C), while a coordination change from 9 to 8 was established for the Cm(H2PO4)2+ species with increasing temperature [8]. This change of coordination upon increasing temperature, which has not been investigated in detail in the past, might also be relevant in the complexation of other f-elements with inorganic and/or organic ligands and deserves further exploration.

[1] R. C. Ewing, Proc. Natl. Acad. Sci. USA 96, 3432 (1999).
[2] D. Bregiroux et al., J. Nucl. Mater. 366, 52 (2007).
[3] N. Huittinen et al., J. Nucl. Mater. 486, 148 (2017).
[4] E. Du Fou de Kerdaniel, J. Nucl. Mater. 362, 451 (2007).
[5] N. Huittinen et al., Inorg. Chem. 57, 6252−6265 (2018).
[6] H. Moll et al., Radiochim. Acta, 99, 775−782 (2011).
[7] N. Jordan et al., Inorg. Chem. 57, 7015-7024 (2018).
[8] N. Huittinen et al., Inorg. Chem. 60, 10656−10673 (2021).
[9] I. Grenthe et al., Second update on the chemical thermodynamics of uranium, neptunium, plutonium, americium and technetium, OECD Nuclear Energy Agency Data Bank, Eds., OECD Publications, Paris, France, (2020).

Einleitung
Zum ersten Mal wurde ein MR-Scanner (0,22 T) mit einer horizontalen Protonen Pencil Beam Scanning (PBS) Strahlführung integriert. Die Herausforderung hierbei ist die elektromagnetische Wechselwirkung zwischen magnetischen Streufeldern, erzeugt von Strahlsteuermagneten (SSM), und dem statischen Magnetfeld (B0) des MR-Scanners. Diese führt zu Geisterbildartefakten in den MR-Bildern, wie in Abbildung 1 gezeigt[1]. Passive magnetische Abschirmung ist eine mögliche Lösung zur Beseitigung dieser Artefakte. In dieser Studie bestimmen wir den magnetischen Abschirmungsfaktor (MAF), der für eine artefaktfreie MR-Bildgebung während der PBS-Bestrahlung erforderlich ist. Außerdem untersuchen wir die Auswirkung von Design-Parametern einer passiven magnetischen Abschirmung, die um die SSMs positioniert ist, auf die Reduzierung der Stärke ihrer Streufelder.
Material & Methoden
Eine Magnetfeldkamera (MFK) wurde im MR-Isozentrum positioniert um Änderungen vom B0-Feld (ΔB0) aufgrund des Streufelds der SSMs zu messen. Variiert wurden dabei sowohl die Strahlfeldgröße als auch der Abstand zwischen MR-Isozentrum und PBS-Isozentrum. Für verschiedene Parameterkombinationen wurden Bilder des ACR Small Phantoms während der Bestrahlung aufgenommen, und die prozentuale Signal Ghosting Ratio (PSGR) berechnet, um den maximalen ΔB0-Wert zu bestimmen, für welchen das ACR-Kriterium von PSGR ≤ 0,025 noch erfüllt wurde[2].
Finite-Elemente-Modell (FEM) Simulationen der PBS-Strahlführung wurden durchgeführt, um die von den SSMs erzeugten magnetischen Streufelder zu berechnen. Für eine magnetische Abschirmung wurden verschiedene Parameter untersucht, wie Geometrie, Materialdicke, Anzahl der Schichten und Größe dazwischenliegenden Luftspalts. Der MAF wurde an der Position des MR-Isozentrums berechnet.
Ergebnisse
Die MFK-Messungen ergaben, dass der maximale ΔB0-Wert 5,66 μT betrug. Der PSGR-Test wurde nur bei Feldgrößen von 1,2, 4 und 12 cm und bei Abständen von 0,3, 1,3 bzw. 2,3 m zwischen dem PBS- und MR-Isozentrum bestanden. In diesen Fällen betrug der maximale ΔB0-Wert 0,27 μT. Daher ist für eine artefaktfreie MR-Bildgebung während der PBS-Dosisabgabe ein Mindestabschirmungsfaktor von 20,22 erforderlich.
Auf der Grundlage von FEM-Simulationen lässt sich dieser MAF am effektivsten durch eine mehrschichtige zylindrische Abschirmung erreichen. Ein MAF von 21 wurde durch die Verwendung von zwei konzentrischen Schichten mit einer Dicke von jeweils 10 mm und einem Luftspaltabstand von 10 mm erreicht.
Diskussion
Der magnetische Abschirmungsfaktorwurde experimentell für den 0,22-T-In-Beam-MR-Scanner Beamline bestimmt. Computersimulationen zeigten, dass dieser Abschirmungsfaktor mit einer passiven magnetischen Abschirmung erreicht werden kann, wobei eine mehrschichtige konzentrische Geometrie aus Kohlenstoffstahl mit einem Luftspalt zwischen den Schichten verwendet wird.

Literatur
[1] S. Gantz et al. 2020 Phys. Med. Biol.
[2] Small Phantom Guide, American College of Radiology

Modern High Performance Computing (HPC) systemsare built with innovative system architectures and novelprogramming models to further push the speed limit of computing.The increased complexity poses challenges for performanceportability and performance evaluation. The Standard PerformanceEvaluation Corporation (SPEC) has a long history ofproducing industry-standard benchmarks for modern computersystems. SPEC’s newly released SPEChpc 2021 benchmark suites,developed by the High Performance Group, are a bold attempt toprovide a fair and objective benchmarking tool designed for state-HPC, SPEC, HPG, SPEChpc 2021, benchmarks,performance benchmarking and analysis, heterogeneity, offloading,MPI, MPI+X, OpenMP, OpenACCof-the-art HPC systems. With the support of multiple host andaccelerator programming models, the suites are portable acrossboth homogeneous and heterogeneous architectures. Differentworkloads are developed to fit system sizes ranging from a fewcompute nodes to a few hundred compute nodes. In this work wepresent our first experiences in performance benchmarking thenew SPEChpc2021 suites and evaluate their portability and basicperformance characteristics on various popular and emergingHPC architectures, including x86 CPU, NVIDIA GPU, and AMDGPU. This study provides a first-hand experience of executingthe SPEChpc 2021 suites at scale on production HPC systems,discusses real-world use cases, and serves as an initial guidelinefor using the benchmark suites

Nb-94 is a constituent of the radioactive waste in the dismantling process of nuclear power plants. It has a half-life of 20300 a and has to be considered in the risk assessment [1]. This motivates the need for a suitable Nb-radiotracer, which allows to investigate the interaction of Nb in future waste repositories. Half-life and decay mode suggest the isotope Nb-95 as promising candidate.

Hydrogen isotopes are studied in many research areas to clarify fundamental and applied aspects of their physicochemical behavior. Besides deuterium, the isotope tritium has become the focus of current investigations. One important application is the separation of hydrogen isotopes. Currently available methods have low separation efficiency and high energy consumption. Therefore, approaches to increase efficiency are presently being explored, with a focus on gaseous deuterium.
In our work we will investigate two types of materials, on the one hand membrane materials (graphene and Nafion) and on the other hand nanoporous materials (metal-organic frameworks) with respect to tritium separation. For these studies, we needed to establish an analytical routine for working with gaseous tritium, from access to quantification methods. For this purpose, we employed a tritium manifold that uses heat to release gaseous tritium from a reservoir in a defined manner. The tritium gas under defined pressure and, in the future, mixtures of hydrogen isotopes will be used for separation experiments in flow cells. The gas will eventually be converted to HTO, which will be analyzed by liquid scintillation counting (LSC), where the measured activity directly corresponds to the concentration of tritium in the analyzed sample. To assess the quality of the proposed analytical method, the data obtained from the LSC measurements were compared with the calculated values and with the pressures applied during tritium dosing from the manifold. The measured values correspond directly to the applied pressures and agree well with the calculated data. These results indicate the proficiency of the established analytical approach, which allows to explore the proposed separation methods with high precision.

Bergmann’s Rule—which posits that larger animals live in colder areas—is thought to influence variation in body size within species across space and time, but evidence for this claim is mixed. We tested four competing hypotheses for spatio-temporal variation in body size within bat species during the past two decades across North America: (1) the heat conservation hypothesis, which posits that increased body size facilitates body heat conservation (and which is the traditional explanation for the mechanism underlying Bergmann’s Rule); (2) the heat mortality hypothesis, which posits that increased body size increases susceptibility to acute heat stress; (3) the resource availability hypothesis, which posits that increased body size is enabled in areas with more abundant food; and (4) the starvation resistance hypothesis, which posits that increased body size reduces susceptibility to starvation during acute food shortages. Bayesian hierarchical models revealed that spatial variation in body mass was most consistently (and negatively) correlated with mean annual temperature, supporting the heat conservation hypothesis. Across time, variation in body mass was most consistently (and positively) correlated with net primary productivity, supporting the resource availability hypothesis. Climate change could influence body size in animals through both changes in mean annual temperature and in resource availability. Rapid reductions in body size associated with increasing temperatures have occurred in short-lived, fecund species, but such reductions likely transpire more slowly in longer-lived species.

Background: The photon strength functions (PSFs) and nuclear level density (NLD) are key ingredients for
calculation of the photon interaction with nuclei, in particular the reaction cross sections. These cross sections are
important especially in nuclear astrophysics and in the development of advanced nuclear technologies.
Purpose: The role of the scissors mode in the M1 PSF of (well-deformed) actinides was investigated by several
experimental techniques. The analyses of different experiments result in significant differences, especially on the
strength of the mode. The shape of the low-energy tail of the giant electric dipole resonance is uncertain as well.
In particular, some works proposed a presence of the E1 pygmy resonance just above 7 MeV. Because of these
inconsistencies additional information on PSFs in this region is of great interest.
Methods: The γ -ray spectra from neutron-capture reactions on the 234U, 236U, and 238U nuclei have been
measured with the total absorption calorimeter of the n_TOF facility at CERN. The background-corrected
sum-energy and multi-step-cascade spectra were extracted for several isolated s-wave resonances up to about
140 eV.
Results: The experimental spectra were compared to statistical model predictions coming from a large selection
of models of photon strength functions and nuclear level density. No combination of PSF and NLD models from
literature is able to globally describe our spectra. After extensive search we were able to find model combinations
with modified generalized Lorentzian (MGLO) E1 PSF, which match the experimental spectra as well as the total
radiative widths.
Conclusions: The constant temperature energy dependence is favored for a NLD. The tail of giant electric dipole
resonance is well described by the MGLO model of the E1 PSF with no hint of pygmy resonance. The M1 PSF
must contain a very strong, relatively wide, and likely double-resonance scissors mode. The mode is responsible
for about a half of the total radiative width of neutron resonances and significantly affects the radiative cross
section.

Nuclear astrophysics with accelerator mass spectrometry

Most patients with head and neck squamous cell carcinomas (HNSCC) are diagnosed at a locally advanced stage and show heterogeneous treatment responses. Low SLC3A2 (solute carrier family 3 member 2) mRNA and protein (CD98hc) expression levels are associated with higher locoregional control in HNSCC patients treated with primary radiochemotherapy or postoperative radiochemotherapy, suggesting that CD98hc could be a target for HNSCC radiosensitization. One of the targeted strategies for tumor radiosensitization is precision immunotherapy, e.g., the use of chimeric antigen receptor (CAR) T cells. This study aimed to define the potential clinical value of new treatment approaches combining conventional radiotherapy with CD98hc-targeted immunotherapy. To address this question, we analyzed the antitumor activity of the combination of fractionated irradiation and switchable universal CAR (UniCAR) system against radioresistant HNSCC cells in 3D culture. CD98hc-redirected UniCAR T cells showed the ability to destroy radioresistant HNSCC spheroids. Also, the infiltration rate of the UniCAR T cells was enhanced in the presence of the CD98hc target module. Furthermore, sequential treatment with fractionated irradiation followed by CD98hc-redirected UniCAR T treatment showed a synergistic effect. Taken together, our obtained data underline the improved antitumor effect of the combination of radiotherapy with CD98hc-targeted immunotherapy. Such a combination presents an attractive approach for the treatment of high-risk HNSCC patients.

The oxygen evolution reaction is central to making chemicals and energy carriers using electrons. Combining the great tunability of enzymatic systems with known oxide-based catalysts can create breakthrough opportunities to achieve both high activity and stability. Here we report a series of metal hydroxide–organic frameworks (MHOFs) synthesized by transforming layered hydroxides into two-dimensional sheets crosslinked using aromatic carboxylate linkers. MHOFs act as a tunable catalytic platform for the oxygen evolution reaction, where the π–π interactions between adjacent stacked linkers dictate stability, while the nature of transition metals in the hydroxides modulates catalytic activity. Substituting Ni-based MHOFs with acidic cations or electron-withdrawing linkers enhances oxygen evolution reaction activity by over three orders of magnitude per metal site, with Fe substitution achieving a mass activity of 80 A g_catalyst ^-1 at 0.3 V overpotential for 20 h. Density functional theory calculationscorrelate the enhanced oxygen evolution reaction activity with the MHOF-based modulation of Ni redox and the optimized binding of oxygenated intermediates.

Density Functional Theory (DFT) is the most common tool for investigating materials under extreme conditions, yet its scaling behavior with respect to both system size and temperature prohibits large scale simulations in such regimes. Progress in this regard would enable accurate modeling of planetary interiors or radiation damage in fusion reactor walls.
One possible route to alleviate these scaling problems is through the use of surrogate models, i.e., machine-learning models. These are trained on DFT data and are able to reproduce DFT predictions of energies and forces at comparable accuracy, but negligible computational cost.
Yet, in order to avoid repeated costly training data generation, models need to be able to transfer across length scales. Here, we present such transferability results. They show how learning local information can allow models to extrapolate to length scales that are not attainable with standard DFT methods. The models are based upon the Materials Learning Algorithms (MALA) package [1] and the therein implemented LDOS based machine learning workflow [2].

[1]: https://github.com/mala-project
[2]: J. A. Ellis et al., Phys. Rev. B 104, 035120, 2021

While the high efficiency of Density Functional Theory (DFT) calculations have enabled many important materials science application over the past decades, modern scientific problems require accurate electronic structure data beyond the scales attainable with DFT. For instance, the modeling of materials at extreme conditions across multiple length and time scales, which is important for the understanding for physical phenomena such as radiation damages in fusion reactor walls, evades ab-initio treatment.
One possible method to obtain such models at near ab-initio accuracy are DFT surrogate models, that, based on machine learning (ML) algorithms, reproduce DFT results at a fraction of the cost. One drawback of the ML workflow is the need for hyperparameter optimization, i.e., the need to tune the employed ML algorithm in order to best perform on the given dataset. Manually performing this optimization becomes prohibitive if a wide range of materials and conditions is eventually to be treated. Here, we present results of an hyperparameter study in an effort to find optimal surrogate models for aluminium at ambient conditions [1], that investigates how modern hyperparameter optimization techniques can be used to automate large parts of the model selection process and eventually move towards automated surrogate model creation. The models are based upon the Materials Learning Algorithms (MALA) package [2] and the therein implemented LDOS based machine learning workflow [3].
[1]: https://www.doi.org/10.14278/rodare.1107
[2]: https://www.doi.org/10.5281/zenodo.5557254
[3]: https://www.doi.org/10.1103/PhysRevB.104.035120

We have successfully employed high-brightness liquid metal ion sources (LMIS) for the investigation of the
interaction of metal and metalloid ions with strong field laser beams. The gold and silicon ions, generated in the
LMIS by electrostatic field ionization, can be further ionized up to Au11+ and Si4+ with Thales laser (1 kHz)
at intensities of up to 4e16 W/cm2. Furthermore, we employed the fiber laser with 100 kHz to manipulate
the recoil momenta with subcycle resolution.

Due to the growing importance of Computational Fluid Dynamics (CFD) for reactor safety research, there have been activities aimed at qualifying the associated methods for many years. This entails the development and validation of models on the basis of detailed experimental data, generated in comprehensive projects. There was and is a need for development, among other things, for multiphase flows, in particular for accident scenarios in the reactor coolant system (RCS). In order to be able to use the model developments and validation data generated throughout the various projects funded by the German Federal Ministry for Economic Affairs and Energy in the long term, these are carried out using the reference code OpenFOAM, which is thereby qualified for application. The OpenFOAM_RCS project includes the OpenFOAM_RCS Addon for the C++ library OpenFOAM from the OpenFOAM Foundation, which gathers additional software that is relevant for the simulation of the reactor cooling system. This entails solvers, physical models, functionObjects, boundary conditions as well as pre- and post-processing utilities. The associated simulation setups are maintained along with the code.

Aggressive pheochromocytomas and paragangliomas (PPGLs) are difficult to treat, and molecular targeting is being increasingly considered, but with variable results. This study investigates established and novel molecular-targeted drugs and chemotherapeutic agents for the treatment of PPGLs in human primary cultures and murine cell line spheroids. In PPGLs from 33 patients, including 7 metastatic PPGLs, we identified germline or somatic driver-mutations in 82% of cases, allowing us to assess potential differences in drug responsivity between pseudohypoxia-associated cluster 1- (n=11) and kinase signaling-associated cluster 2-related (n=14) PPGL primary cultures. Single anti-cancer drugs were either more effective in cluster 1 (cabozantinib, selpercatinib, 5-FU) or similarly effective in both clusters (everolimus, sunitinib, alpelisib, trametinib, niraparib, gemcitabine, AR-A014418, high-dose zoledronic acid). Estrogen and low-dose zoledronic acid were the only single substances more effective in cluster 2. Neither cluster 1- nor cluster 2-related patient primary cultures responded to HIF-2α inhibitors, temozolomide, dabrafenib, or octreotide. We showed particular efficacy of targeted combination treatments (cabozantinib/everolimus, alpelisib/everolimus, alpelisib/trametinib) in both clusters, with higher efficacy in cluster 2 and overall synergistic effects (cabozantinib/everolimus, lpelisib/trametinib) or synergistic effects in cluster 2 (alpelisib/everolimus). Cabozantinib/everolimus combination therapy, gemcitabine, and high-dose zoledronic acid appear to be the very promising treatment options with particularly high efficacy in SDHB-mutant and metastatic tumors. In conclusion, only minor differences regarding drug responsivity were found between cluster 1 and cluster 2: Some single anti-cancer drugs were more effective in cluster 1 and targeted combination treatments were more effective in cluster 2.

2D transition metal carbides and/or nitrides, so-called MXenes, are noted as ideal fast-charging cation-intercalation electrode materials, which nev-ertheless suffer from limited specific capacities. Herein, it is reported that constructing redox-active phosphorus−oxygen terminals can be an attractive strategy for Nb4C3 MXenes to remarkably boost their specific capacities for ultrafast Na+ storage. As revealed, redox-active terminals with a stoichio-metric formula of PO2- display a metaphosphate-like configuration with each P atom sustaining three PO bonds and one PO dangling bond. Compared with conventional O-terminals, metaphosphate-like terminals empower Nb4C3 (denoted PO2-Nb4C3) with considerably enriched carrier density (four-fold), improved conductivity (12.3-fold at 300 K), additional redox-active sites, boosted Nb redox depth, nondeclined Na+-diffusion capability, and buffered internal stress during Na+ intercalation/de-intercalation. Consequently, com-pared with O-terminated Nb4C3, PO2-Nb4C3 exhibits a doubled Na+-storage capacity (221.0 mAh g-1), well-retained fast-charging capability (4.9 min at 80% capacity retention), significantly promoted cycle life (nondegraded capacity over 2000 cycles), and justified feasibility for assembling energy−power-balanced Na-ion capacitors. This study unveils that the molecular-level design of MXene terminals provides opportunities for developing simulta-neously high-capacity and fast-charging electrodes, alleviating the energy−power tradeoff typical for energy-storage devices.

The study of matter under extreme densities and temperatures as they occur e.g. in astrophysical
objects and nuclear fusion applications has emerged as one of the most active frontiers in physics,
material science, and related disciplines. In this context, a key quantity is given by the dynamic
structure factor S(q, ω), which is probed in scattering experiments—the most widely used method
of diagnostics at these extreme conditions. In addition to its crucial importance for the study of
warm dense matter, the modelling of such dynamic properties of correlated quantum many-body
systems constitutes one of the most fundamental theoretical challenges of our time. Here we report
a hitherto unexplained roton feature in S(q, ω) of the warm dense electron gas, and introduce a
microscopic explanation in terms of a new electronic pair alignment model. This new paradigm
will be highly important for the understanding of warm dense matter, and has a direct impact on
the interpretation of scattering experiments. Moreover, we expect our results to give unprecedented
insights into the dynamics of a number of correlated quantum many-body systems such as ultracold
helium, dipolar supersolids, and bilayer heterostructures.

MXenes are emerging layered materials that are promising for electrochemical energy storage and (opto-)electronic applications. A fundamental understanding of charge transport in MXenes is essential for such applications, but has remained under debate. While theoretical studies pointed to efficient band transport, device measurements have revealed thermally activated, hopping-type transport. Here we present a unifying picture of charge transport in two model MXenes by combining ultrafast terahertz and static electrical transport measurements to distinguish the short- and long-range transport characteristics. We find that band-like transport dominates short-range, intra-flake charge conduction in MXenes, whereas long-range, inter-flake transport occurs through thermally activated hopping, and limits charge percolation across the MXene flakes. Our analysis of the intra-flake charge carrier scattering rate shows that it is dominated by scattering from longitudinal optical phonons with a small coupling constant (α ≈ 1), for both semiconducting and metallic MXenes. This indicates the formation of large polarons in MXenes. Our work therefore provides insight into the polaronic nature of free charges in MXenes, and unveils intra- and inter-flake transport mechanisms in the MXene materials, which are relevant for both fundamental studies and applications.

We present extensive new direct path-integral Monte Carlo results for electrons in quantum dots in two and three dimensions. This allows us to investigate the nonclassical rotational inertia (NCRI) of the system, and we find an abnormal negative superfluid fraction [Phys. Rev. Lett. 112, 235301 (2014)] under some conditions. In addition, we study the structural properties by computing a sophisticated center-two particle correlation function. Remarkably, we find no connection between the spatial structure and the NCRI, since the former can be nearly identical for Fermi- and Bose-statistics for parameters where the superfluid fraction is diverging towards negative infinity.

We present extensive new ab initio path integral Monte Carlo (PIMC)
simulations of the uniform electron gas (UEG) in the high-temperature regime,
8 ≤ θ = kBT /EF ≤ 128. This allows us to study the convergence of different
properties towards the classical limit. In particular, we investigate the classical relation
between the static structure factor S(q) and the static local field correction G(q),
which is only fulfilled at low densities. Moreover, we compare our new results for
the interaction energy to the parametrization of the UEG by Groth et al. [PRL 119,
135001 (2017)], which interpolates between PIMC results for θ ≤ 8 and the Debye-
H ̈uckel limit, and to higher order analytical virial expansions. Finally, we consider the
momentum distribution function n(q) and find an interaction-induced increase in the
occupation of the zero-momentum state even for θ & 32. All PIMC data are freely
available online, and can be used as input for improved parametrizations and as a
rigorous benchmark for approximate methods.

The properties of hydrogen under extreme conditions are important for many applications, including inertial confinement fusion and astrophysical models. A key quantity is given by the electronic density response to an external perturbation, which is probed in X-ray Thomson scattering (XRTS) experiments -- the state of the art diagnostics from which system parameters like the free electron density , the electronic temperature , and the charge state can be inferred. In this work, we present highly accurate path integral Monte Carlo (PIMC) results for the electronic density response of hydrogen. We obtain the exchange-correlation (XC) kernel , which is of central relevance for many applications, such as time-dependent density functional theory (TD-DFT). This gives us a first unbiased look into the electronic density response of hydrogen in the warm-dense matter regime, thereby opening up a gamut of avenues for future research.

We combine ab initio path integral Monte Carlo (PIMC) simulations with fixed ionic configurations, obtained by DFT-MD simulations, in order to solve the electronic problem for hydrogen under warm dense matter conditions. To solve the divergence problem in the Ewald-sum for attractive potentials we employ the pair-approximation. This approach is compared against the much simpler Kelbg pair-potential. We find very favorable convergence behavior towards the latter. Since PIMC does not require any further assumptions regarding exchange and correlations of the many-body system, we then compare electronic densities obtained from our snapshot PIMC calculations with DFT calculations in the metallic regime. Furthermore, we investigate the manifestation of the resulting fermionic sign problem in our snapshot PIMC simulations. This gives us the unique capability to study the properties of warm dense hydrogen from ab initio simulations without any further assumptions, like the functional form of the exchange-correlation effects or fixed fermionic nodes. Thus, snapshot PIMC enables us to obtain the exact density response of warm dense hydrogen. This is extremely valuable to both experiments, like X-Ray Thomson scattering, as well as the development of new XC-functionals.

Long-term care facilities have been widely affected by the COVID-19 pandemic. Retirement homes are particularly vulnerable due to the higher mortality risk of infected elderly individuals. Once an outbreak is happening, suppressing the spread of the virus in retirement homes is challenging because the residents are in contact with each other and isolation measures cannot be widely enforced. Regular testing strategies, on the other hand, have been shown to effectively prevent outbreaks in retirement homes. However, high frequency testing may consume substantial staff working time, which results a trade-off between the time invested in testing, and the time spent providing essential care to residents.
Thus, developing an optimal testing strategy is crucial to proactively detect infections while guaranteeing efficient use of limited staff time in these facilities.
Although numerous efforts have been made to prevent the virus from spreading in long-term care facilities, this is the first study to develop testing strategies based on formal optimization methods.
This paper proposes two novel optimization models for testing schedules. The models aim to minimize the risk of infection in retirement homes, considering the trade-off between the probability of infection and staff workload. We employ a probabilistic approach in conjunction with the optimization models, to compute the risk of infection, including contact rates, incidence status, and the probability of infection of the residents.
To solve the models, we propose an enhanced local search algorithm by leveraging the \textit{symmetry property} of the optimal solution. We perform several experiments with realistically sized instances and show that the proposed approach can derive optimal testing strategies.

We provide post-processing data of daily dead and infected COVID-19 cases for a county (Landkreise) and a state (Bundesland) level. The data are extracted from the following link the data source, and subsequently transferred to the Casus-HZDR database server (see Fig above). The age-based and gender-based data are then aggregated and prepared in csv file.

The current data for county level is prepared on Germany_Counties_COVID19_Death_Infections.csv and its daily version is stored in Archive folder. Likewise, the actual data for state level is prepared on Germany_States_COVID19_Death_Infections.csv and its daily version is stored in Archive folder. The file consists of six columns such as region, name, date, dead, infected and population. The region denotes the ID of a county/state followed by its name in the next column. The inserted date of data is prepared in the third column followed by the number of dead and infected cases. Last but not least, the population of the county is provided in the last column.

Average-atom (AA) models are an important tool in the modelling of warm dense matter, being both a computationally cheap and conceptually straightforward alternative to full DFT MD simulations. AA models are typically based on a common premise - namely, an atom immersed in a plasma environment - but use a range of different assumptions and approximations, which can cause inconsistent predictions for various properties. In this talk, I will compare results across several models, differing for example in their choice of boundary conditions and exchange-correlation functional. I will focus on the mean ionization state (MIS), an important property in WDM. I will compare different methods for computing the MIS, including methods which are historically popular and still widely-used in AA codes, and also consider more novel approaches using the electron localization function and Kubo-Greenwood formalism. If time permits, these results with also be compared with results from full DFT-MD simulations.

Density-functional average-atom (AA) models are an important tool in simulations of the warm dense matter (WDM) regime, because they account for quantum interactions at favourable computational cost. AA models are typically based on a common premise - namely, an atom immersed in a plasma environment - but use a range of different assumptions and approximations, leading to inconsistent predictions for various properties. We compare results across several models, differing for example in their choice of boundary conditions and exchange-correlation functional, focussing on the mean ionization state (MIS), an important property in WDM. Furthermore, we compare different methods for evaluating the MIS: a simple energy threshold, and approaches based on the inverse participation function and electron localization function. We evaluate the relative merits of these approaches and, time-permitting, compare our AA results with full Kohn-Sham density-functional theory calculations.

With the merits of quantum dots (QDs) (e.g., high molar extinction coefficient, strong visible light absorption, large specific surface area, and abundant functional surface active sites) and aerogels (e.g., self-supported architectures, porous network), semiconductor QD aerogels show great prospect in photocatalytic applications. However, typical gelation methods rely on oxidative treatments of QDs. Moreover, the remaining organic ligands (e.g., mercaptoacids) are still present on the surface of gels. Both these factors inhibit the activity of such photocatalysts, hampering their widespread use.
Herein, we present a facile 3D assembly of II−VI semiconductor QDs capped with inorganic (NH₄)₂S ligands into aerogels using H₂O as a dispersion solvent. Without any sacrificial agents, the resulting CdSe QD aerogels achieve a high CO generation rate of 15 μmol g^-1 h^-1, which is 12-fold higher than that of pristine-aggregated QD powders. Our work not only provides a facile strategy to fabricate QD aerogels but also offers a platform for designing advanced aerogel-based photocatalysts.

Transglutaminase 2 (TGase 2) represents a multifunctional protein, which is involved in various physiological and pathophysiological processes. The latter also include its participation in the development and progression of malignant neoplasms, which is often accompanied by an in-creased protein synthesis. Besides the elucidation of the molecular functions of TGase 2 in tumor cells, knowledge of its concentration that is available for targeting by theranostic agents repre-sents a valuable information. Herein, we describe the application of a recently developed fluo-rescence anisotropy (FA)-based assay for the quantitative expression profiling of TGase 2 by means of transamidase-active enzyme in cell lysates. The assay is based on the incorporation of rhodamine B‑isonipecotyl‑cadaverine (R-I-Cad) into N,N-dimethylated casein (DMC), which results in an increase of FA signal over time. It was shown that this reaction is not only catalyzed by TGase 2 but also by TGases 1, 3, and 6 and factor XIIIa using recombinant proteins. Therefore, control measurements in the presence of a selective irreversible TGase 2 inhibitor were manda-tory to ascertain the specific contribution of TGase 2 to the overall FA rate. To validate the assay regarding the quality of quantification, spike/recovery and linearity of dilution experiments were performed. A total of 25 cancer and 5 non-cancer cell lines were characterized with this as-say method in terms of their activatable TGase 2 concentration (fmol/µg protein lysate) and the results were compared to protein synthesis data obtained by western blotting. Moreover, com-plementary protein quantification methods using a biotinylated irreversible TGase 2 inhibitor as activity-based probe and a commercially available ELISA were applied for selected cell lines to further validate the results obtained by the FA-based assay. Overall, the present study demonstrates that the FA-based assay using the substrate pair R-I-Cad and DMC represents a facile, homogenous and continuous method for quantifying TGase 2 activity in cell lysates.

Modern particle accelerators are a key component of today’s research landscape and indispensable in industry and medicine. In special application areas, the portfolio of these facilities will be expanded by laser-driven compact plasma accelerators that generate short, high-intensity pulses of ions with unique beam properties. Though intensely explored by the community, scaling the maximum beam energies of laser-driven ion accelerators to the required level is one of the most significant challenges of this field. This endeavor is inherently linked to a fundamental understanding of the underlying acceleration processes. The prospect to effciently increase the beam energy relies on the ability to control the accelerating field structures beyond the well-established acceleration from the stationary target rear side. However, manipulating the interaction in such micrometer-sized accelerators proves to be challenging due to the transient nature of the plasma fields and requires precise tuning of the temporal laser pulse shape and the volumetric density distribution of the plasma target to a level that could so far not be achieved.
This thesis investigates laser-proton acceleration using a cryogenic hydrogen target that combines the capabilities of predictive three-dimensional simulation and the in-situ realtime monitoring of the density distribution in the experiment to explore the fundamental physical principles of plasma based acceleration mechanisms. The corresponding experiments were performed at the DRACO laser facility at the Helmholtz-Zentrum Dresden-Rossendorf. The key to the success of these studies was the advancement of the cryogenic target system that generates a self-replenishing pure hydrogen jet. Using a mechanical chopping device, which protects the target system from the disruptive influence originating from the high-intensity interaction, allowed, for the first time, systematic experiments with a large number of laser shots in the harsh environment of the ultra-short pulse DRACO petawatt laser. The performance of a cylindrical hydrogen jet can be substantially optimized by a flexible all-optical tailoring of the target profile. Guided by real-time multi-color probing, the target density, the decisive parameter of the interaction, was scanned over two orders of magnitude allowing the exploration of different advanced acceleration regimes in a controlled manner. This approach led to the experimental realization of proton beams with energies up to 80 MeV and application relevant high particle yield from advanced acceleration mechanisms occurring in near-critical density plasmas, a regime so far mostly investigated in numerical studies. Besides cylindrical jets, the formation of thin hydrogen sheets was studied to gain insight into the fluid and crystallization dynamics that can be used to tailor the target shape for laser-proton acceleration. Using these jets, the onset of target transparency was explored, a regime that promises increased proton energies when optimized. Furthermore, after irradiation of the hydrogen jet with a high-intensity laser pulse, an unexpected axial modulation in the plasma density distribution was observed that can play a role in structuring the proton beam profile. This modulation is caused by instabilities that originate from the laser-plasma interaction, for example due to laser-driven return currents or the plasma expansion dynamics.

Background: Gold mining activities in South Africa resulted in contamination of residential environment with uranium-rich wastes from mine tailings. Health of the people living around the mine tailings could be affected by uranium exposure due to its hazardous chemotoxic and radiological properties.
Methods: We conducted a cross-sectional study to assess i) uranium (U) concentrations in individual hair samples of children and adults living in close proximity to mine tailings in Northeast-Soweto in Johannesburg, South Africa, and ii) the association between U concentrations in hair and various factors, including zone of residence, socio-demographic and housing characteristics. Sampling sites were divided into three zones based on the distance between a dwelling and a cluster of mine tailings (zone 1: <= 500 m, zone 2: 2-3 km away, zone 3: 4-5 km away). U concentrations in hair samples were measured using inductively coupled plasma mass spectrometry. To test the association between U concentrations and selected factors we used robust regression models with log-transformed U concentrations.

Heterogeneous hardware landscapes will define the Exascale era. At the same time, keeping scientific libraries and applications portable across different hardware setups while maintaining high performance is no trivial matter. Vendor-provided programming platforms often cannot target accelerators from other vendors, and different hardware types like CPUs, GPUs and FPGAs require differently tuned algorithms for optimal performance.

A solution to these issues can be found in abstraction layers that provide the user with a single programming interface while still maintaining portability and performance. In this talk, we introduce the Caravan HPC ecosystem. With the alpaka abstraction library for accelerator programming at its core and many sibling libraries for related use cases --- such as the memory access abstraction layer LLAMA or the C++ primitives library vikunja --- the Caravan ecosystem is an ideal choice for scientists and programmers setting out to tackle the challenges of the Exascale era.

It is common in the HPC community that the achieved performance with just CPUs is limited for many computational cases. The EuroHPC pre-exascale and the coming exascale systems are mainly focused on accelerators, and some of the largest upcoming supercomputers such as LUMI and Frontier will be powered by AMD Instinct™ accelerators. However, these new systems create many challenges for developers who are not familiar with the new ecosystem or with the required programming models that can be used to program for heterogeneous architectures. In this paper, we present some of the more well-known programming models to program for current and future GPU systems. We then measure the performance of each approach using a benchmark and a mini-app, test with various compilers, and tune the codes where necessary. Finally, we compare the performance, where possible, between the NVIDIA Volta (V100), Ampere (A100) GPUs, and the AMD MI100 GPU.

The management of mine tailings presents a global challenge. Re-mining of tailings to recover remaining metals and other valuable constituents could play a crucial role in reducing the volume of stored tailings. To assess the resource potential of tailings storage facilities, 3D resource models must be constructed. This is not straightforward owing to the heterogeneous nature of tailings. In this case study, modelling of the Davidschacht tailings deposit was performed using universal sequential Gaussian simulation, to account for the strong trends and heterogeneity. The tonnages of the valuable elements were estimated with reasonable certainty, confirming that relatively few drill holes are required for robust resource estimates of tailings storage facilities. Zinc is the most abundant valuable metal (6,270 t ±10 %), followed by Pb (2,480 t ±10 %), Cu (654 t ±11 %), and In (12.6 t ±9 %), with errors given for 95 % confidence levels. Although the In tonnage is low compared to the other elements, its in situ value is around half that of Cu and Pb, demonstrating the importance of high value by-products for re-mining potential. Although tailings deposits typically have lower grades and tonnages than primary ore deposits, and the quantities of recoverable valuable elements may be even lower due to current technological limitations, re-mining of TSFs should also be considered for rehabilitation purposes and may help to diversify raw materials supply chains. Geostatistical modelling, particularly universal kriging-based simulation, has been proven to produce robust tonnage estimates of tailings storage facilities and should be adopted in industry to reduce the technical and financial uncertainties associated with re-mining.

We report the development of a multipurpose differential X-ray calorimeter with a broad energy bandwidth. The absorber architecture is combined with a Bayesian unfolding algorithm to unfold high-energy X-ray spectra generated in high-intensity laser-matter interactions. Particularly, we show how to extract absolute energy spectra and how our unfolding algorithm can reconstruct features not included in the initial guess. The performance of the calorimeter is evaluated via Monte Carlo generated data. The method accuracy to reconstruct electron temperatures from bremsstrahlung is shown to be 5 % for electron temperatures from 1 MeV to 50 MeV. We study bremsstrahlung generated in solid target interaction showing an electron temperature of 0.56±0.04MeV for a 700 µm Ti titanium target and 0.53±0.03MeV for a 50 µm target. We investigate bremsstrahlung from a target irradiated by laser wakefield accelerated electrons showing an endpoint energy of 551 ± 5 MeV, inverse Compton generated X-rays with a peak energy of 1.1 MeV and calibrated radioactive sources. The total energy range covered by all these sources ranges from 10 keV to 551 MeV.

The openPMD API is a DSL used in plasma physical simulations for the description of particle-mesh data according to the openPMD standard. By defining only the logical structure, but not the physical implementation of such data, this standard allows the openPMD API to offer a number of flexibly interchangeable efficient implementations in terms of IO backends. Performance trends in the HPC domain show the increasing necessity for such IO flexibility in data analysis pipelines. This seminar talk will give an introduction on openPMD as well as the openPMD API. It will further discuss current IO trends and the role of the openPMD API therein. A short hands-on demonstration will show the current state of affairs.

BACKGROUND
Amide proton transfer (APT) imaging is a chemical exchange saturation transfer (CEST) technique offering potential clinical applications in patients with brain tumors.

PURPOSE
To investigate whether cerebral APT-CEST is sufficiently reproducible in healthy tissue and glioma for clinical use at 3T.

STUDY TYPE
Prospective, longitudinal

SUBJECTS
Twenty-one healthy volunteers (M:F = 10:11; age 39±11 years) and six glioma patients (M:F = 3:3; age 50±17 years: four glioblastomas, one oligodendroglioma, one suspected low-grade glioma).

FIELD STRENGTH/SEQUENCE
3T, SPACE-CEST

ASSESSMENT
APT-CEST measurement reproducibility was assessed within-session (glioma patients, healthy volunteers), and between-sessions and between-days (healthy volunteers). The standard deviation of the within-subject difference (SDdiff) was calculated in tumor regions of interest (ROI), and eight ROIs at relevant locations including a whole-brain ROI.

STATISTICAL TESTS
Brown-Forsythe tests and variance component analyses (VCA) were used to assess the reproducibility of ROIs for the three reproducibility time intervals. Intraclass correlation coefficient (ICC) was used to assess agreement between the ROIs for the three reproducibility time intervals.

RESULTS
APT-CEST magnetization transfer ratio asymmetry (MTRasym) was 0.89±0.96% on average in healthy brain tissue and 1.59±0.67% in tumor tissue. Intratumoral mean MTRasym was significantly higher than MTRasym in healthy-appearing tissue in patients (0.5±0.46%; P< 0.001). The APTCEST difference between GBMs and contralateral tissue was 1.11%. The average within-session, between-sessions, and between-days SDdiff of healthy control brains was 0.2%. The within-session SDdiff of whole-brain was 0.2% in both healthy volunteers and patients, and 0.21% in the segmented tumor. The orbitofrontal gyri were the ROI with the highest within-session SDdiff (0.61%). Within-session reproducibility of ROIs did not differ significantly from between-sessions or between-day reproducibility (0.76>P>0.22) and VCA showed that within-session variance was the most important factor (60%), but differed from between-days reproducibility in putamen and the central brain (P<0.05). ICC within-session agreement was excellent for glioma (ICC=0.97) and healthy brain in volunteers (ICC=0.81). The effect size of the APTCEST between healthy brain and GBM was 5.

CONCLUSION
Cerebral APT-CEST imaging has good scan-rescan reproducibility in healthy tissue and tumors with clinically feasible scan times at 3T. Short-term measurement effects are dominant components in reproducibility.

Plasmonic sensing in the infrared region employs the direct interaction of the vibrational fingerprints of molecules with the plasmonic resonances, creating surface-enhanced sensing platforms that are superior to traditional spectroscopy. However, the standard noble metals used for plasmonic resonances suffer from high radiative losses as well as fabrication challenges, such as tuning the spectral resonance positions into mid- to far-infrared regions, and the compatibility issue with the existing complementary metal–oxide-semiconductor (CMOS) manufacturing platform. Here, we demonstrate the occurrence of mid-infrared localized surface plasmon resonances (LSPR) in thin Si films hyperdoped with the known deep-level impurity tellurium. We show that the mid-infrared LSPR can be further enhanced and spectrally extended to the far-infrared range by fabricating two-dimensional arrays of micrometer-sized antennas in a Te-hyperdoped Si chip. Since Te-hyperdoped Si can also work as an infrared photodetector, we believe that our results will unlock the route toward the direct integration of plasmonic sensors with the on-chip CMOS platform, greatly advancing the possibility of mass manufacturing of high-performance plasmonic sensing systems.

In case radionuclides (RN) enter the food chain and are incorporated by humans, they pose a possible health risk due to their radio- and chemotoxicity. To precisely assess the health risk after oral incorporation of RN with food and beverages and to apply effective decontamination methods, it is mandatory to understand the processes of RN biokinetics on both cellular and molecular scale. Within the joint research project RADEKOR: “Speciation and transfer of radionuclides in the human organism especially taking into account decorporation agents”, quantitative excretion analysis and biokinetic modeling of orally incorporated RN are performed. Additionally, these macroscopic investigations are combined with molecular speciation studies of RN in artificial fluids of the alimentary tract of humans and cytotoxicity studies with respective human and rat cell lines both in the absence and presence of decorporation agents. Aim of the project is to expand the knowledge of processes underlying RN interactions within the human alimentary tract on a cellular and molecular scale to establish a precise biokinetic model as well as to contribute to the development and improvement of nuclide specific decontamination methods.
This joint project is funded by the German Federal Ministry of Education and Research (grant number 02NUK057). The funding period is from July 2020 to December 2023 and cooperation partners are: Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Technische Universität Dresden (TUD), Leibniz-Universität Hannover (LUH), Karlsruhe Institute of Technology (KIT), and VKTA - Radiation Protection, Analytics & Disposal (VKTA).

Due to the “German Energiewende”, all nuclear power plants (NPPs) in Germany will have been shut down by the end of 2022. Consequently, a safe, economical, and efficient dismantling of the NPPs will be an important challenge for the next decades. This is not only valid for the very particular German case but will certainly foster progress with methods for optimal planning and implementation of decommissioning.
The decommissioning strategy for an NPP requires knowledge of the neutron activation and contamination levels, which have emerged during its operation. Such knowledge can significantly minimize the radioactive waste and contribute to the safety of the operating personnel and the public.
This study considered two strategies. In the first one, the radionuclide inventory in the material of an NPP already under dismantling was investigated. Among others, Co-60 and C-14 in steel samples from the reactor pressure vessel (RPV) and Eu-152, Ba-133 and C-14 in concrete drill cores from biological shielding were quantitatively determined. C-14 was measured by liquid scintillation counting (LSC) after oxidative combustion and the other RN by gamma spectrometry. In the second strategy, the neutron flux in NPPs still under operation was determined with activation monitors. Small metal foils, covering a broad neutron energy range (i.e. thermal, epithermal, and fast energy range), e.g., Ti, Fe, Ni, Cu, In, Sn, Zn, Ta, were placed near the RPV and at the interior and exterior biological shield during the regular annual revision and irradiated for one fuel cycle (approximately one year). After the activation monitors were removed and recovered, the activation of the metal foils was quantitatively determined by gamma spectrometry. The experimental data from both strategies were compared with results from Monte-Carlo simulations.
This work is funded by the German Federal Ministry of Education and Research (BMBF) under grant numbers 15S9412 (WERREBA) and 15S9409A (EMPRADO) and is carried out in cooperation with PreussenElektra GmbH and EWN Greifswald GmbH.

Racemic [18F]FBFP ([18F]1) proved to be a potent σ1 receptor radiotracer with superior imaging properties. The pure enantiomers of unlabeled compounds (S)- and (R)-1 and the corresponding iodonium ylide precursors were synthesized and characterized. The two enantiomers (S)-1 and (R)-1 exhibited comparable high affinity for σ1 receptors and selectivity over σ2 receptors. The Ca2+ fluorescence assay indicated that (R)-1 behaved as an antagonist and (S)-1 as an agonist for σ1 receptors. The 18F-labeled enantiomers (S)- and (R)-[18F]1 were obtained in > 99% enantiomeric purity from the corresponding enantiopure iodonium ylide precursors with radiochemical yield of 24.4% ± 2.6% and molar activity of 86 – 214 GBq/μmol. In ICR mice both (S)- and (R)-[18F]1 displayed comparable high brain uptake, brain-to-blood ratio, in vivo stability and binding specificity in the brain and peripheral organs. In micro-positron emission tomography (PET) imaging studies in rats, (S)-[18F]1 exhibited faster clearance from the brain than (R)-[18F]1, indicating different brain kinetics of the two enantiomers. Both (S)- and (R)-[18F]1 warrant further evaluation in primates to translate a single enantiomer with more suitable kinetics for imaging the σ1 receptors in humans.

Printed magnetic field sensorics enable a new generation of human-machine interfaces and contactless switches for resource efficient printed interactive electronics. As printed magnetoresistors rely on scarce or hard to manufacture magnetosensitive powders, their scalability and demonstration of printing with industry-grade technologies are the key material science challenges. Here, we report dispenser printing of a commodity scale nonmagnetic bismuth-based paste processed by large area laser sintering to obtain printed magnetoresistive sensors. The sensors are printed on different substrates including ceramics, paper and polymer foils. We validate experimentally that the peculiar quantum large orbital magnetoresistive effect remains effective in printed bismuth sensors, allowing their operation in high magnetic fields. The sensors reveal up to 146% resistance change at 5 T at room temperature with a maximum resolution of 2.8 µT. If printed on flexible foils, our sensors show resilience to bending deformation for more than 2000 bending cycles and withstand even thermal forming, as relevant for smart wearables and in-mold electronics. The freedom in the substrate choice and sensor design enabled by dispenser printing allowed us to implement the proposed sensor technology for different applications focused on touchless interactive platforms, such as advertisement materials, interactive wallpapers and printed security panels.

In this introduction, we provide an overview of the papers that were accepted for publication in the feature issue on ultrafast phenomena and terahertz (THz) waves. This feature issue presents cutting-edge research on ultrafast phenomena and highlights recent developments inTHz technology.

The understanding of the formation of the elements has been an intriguing topic within the last decades. It is now approved that the heaviest naturally occurring elements on earth, the actinides, are produced in the astrophysical r-process. However, the exact site of this process is still disputed. Recently, the amount of interstellar Pu-244 (T1/2 = 80.6 Ma) in various geological archives like deep-sea ferromanganese crusts and sediments has been investigated by applying highly sensitive accelerator mass spectrometry measurements (AMS). Correlation of the influx of supernova-produced Fe-60 (T1/2 = 2.6 Ma) and Pu-244 could point to a possible origin of the r-process in the universe. To further prove this hypothesis, recent investigations focus on the determination of another long-lived radionuclide which is also produced in the r process, Cm-247 (T1/2 = 15.6 Ma), by AMS. However, the separation of the expected ultra-trace amounts of actinides (a few 100 atoms per gram) from huge amounts of matrix and interfering elements represents a major analytical challenge. Thus, this contribution aims to compare existing chemical separation strategies for trivalent actinides (Am, Cm) from deep-sea reservoirs, like ferromanganese crusts or nodules based on extraction chromatography. Our investigations show that procedures based on trivalent actinide separation by TRU™ resin fail to extract trivalent actinides from matrices with high concentrations of rare-earth elements. Thus, an alternative separation method based on anion exchange (DOWEX 1x8 for Pu separation) and solvent extraction (DGA™ resin for An/Ln separation and TEVA™ resin for the separation of Am/Cm from rare-earths) has been adapted in our studies. Am-241 and Cm-244 in kBq quantities were used as tracers to determine the yield of the full separation procedure by γ-counting and α spectrometry. The effective separation of trivalent actinides from major matrix elements, like iron and manganese, as well as various rare-earth elements allow for processing multi-gram amounts of deep-sea ferromanganese crusts. This could finally lead to the detection of live Cm-247 in geological archives. Furthermore, this adapted method can be used for the analysis of environmental samples regarding their content and isotopic ratio of anthropogenically produced Pu, Am and Cm which holds potential for nuclear safeguards and nuclear forensics studies.

Due to their applications in catalysis, energy storage or biomedicine, many studies report synthesis and characterizations of CeO2 NPs and intensively use X-ray sources for characterization. In this study, we report a comprehensive interpretation of X-ray measurements on CeO2 models with atomically resolved structure, namely oxo-hydroxo polynuclear Ce complexes. A set of Ce clusters with growing size (0.6 nm to 1.2 nm) and nuclearity (from 6 to 38 Ce atoms) were synthetized and characterized by single crystal XRD. The samples were then analyzed using HEXS and HERFD technics and compared to larger CeO2 NPs and bulk CeO2. Both spectroscopic methods reveal consistent trends as the particle grows or shrink from the set of molecular Ce-{n} clusters up to bulk CeO2. HEXS reveals a broadening in distribution for the short Ce-oxygen bonds for the small clusters. Concomitantly, the HERFD performed at the Ce LIII edge indicates a gradual splitting of the cerium 5d states as the particles become more CeO2 like. From the crystallographic determination of the clusters structure, atomically resolved Ce LIII edge simulation were undertaken. These simulations allow to isolate structural and electronic properties for individual Ce sites within clusters and evidence the great difference between surface and core Ce atoms. It also shows how a combination of simulations from different sites results in the accurate reproduction of the corresponding experimental data. This approach based on clusters atomic sites was then successfully extended to model larger CeO2 NPs Ce LIII edge HERFD spectra. By linking atomically resolved structures to nanoparticles and bulk material using crystallography, X-ray technics and simulation, this work extends the knowledge on cerium oxide nanomaterial and supports a better understanding and predictability of their crystalline and electronic structure

Global road networks continue to expand, and the wildlife responses to these landscape-level changes need to be understood to advise long-term management decisions. Roads have high mortality risk to snakes because snakes typically move slowly and can be intentionally targeted by drivers.
We investigated how radio-tracked King Cobras (Ophiophagus hannah) traverse a major highway in northeast Thailand, and if reproductive cycles were associated with road hazards.
We surveyed a 15.3 km stretch of Highway 304 to determine if there were any locations where snakes could safely move across the road (e.g., culverts and bridges). We used recurse analyses to detect possible road-crossing events, and used dynamic Brownian Bridge Movement Models (dBBMMs) to show movement pathways association with possible unintentional crossing structures. We further used Integrated Step Selection Functions (ISSF) to assess seasonal differences in avoidance of major roads for adult King Cobras in relation to reproductive state.
We discovered 32 unintentional wildlife crossing locations capable of facilitating King Cobra movement across the highway. While our dBBMMs broadly revealed underpasses as possible crossing points, they failed to identify specific underpasses used by telemetered individuals; however, the tracking locations pre- and post-crossing and photographs provided strong evidence of underpass use. Our ISSF suggested a lower avoidance of roads during the breeding season, although the results were inconclusive. With the high volume of traffic, large size of King Cobras, and a 98.8% success rate of crossing the road in our study (nine individuals: 84 crossing attempts with one fatality), we strongly suspect that individuals are using the unintentional crossing structures to safely traverse the road.
Further research is needed to determine the extent of wildlife underpass use at our study site. We propose that more consistent integration of drainage culverts and bridges could help mitigate the impacts of roads on some terrestrial wildlife.

Applications such as actuation by (magnetic) shape memory effects, magnetocaloric cooling and thermomagnetic energy harvesting benefit from a fast martensitic transformation, because using devices at high frequencies increases their power density. Still, data on the speed limit of theses transformations is scarce, as it is difficult to induce the phase transition in short time spans and measure it non-invasively. Up to now, shape memory wires have been heated with currents by Joule heating, which induces a transformation in as short as 20 µs. With magnetic pulses, magnetic shape memory alloys can be transformed within 13 ms. In both cases, however, transformation dynamics are limited by the duration of the current or magnetic pulse.
To increase knowledge about the speed limit of martensitic transformations, here, we heat a 500 nm thick epitaxial Ni-Mn-Ga film with a 7 ns long laser pulse and probe the martensite to austenite transformation with in situ synchrotron diffraction. With this experimental set-up, we can vary the heating rate by changing the laser fluence and additionally adjust the initial sample temperature with a furnace. We observe a linear dependence of the heating rate on the transformation speed. Thus, the transformation can be completed in as little as 10 ns; however, this requires an overheating of several hundreds of Kelvin. For most applications, only a much smaller overheating is feasible, which gives a switching time in the sub-microsecond range. The austenite to martensite transformation can be completed at least within hundreds of ns. This leaves plenty of room to speed up the performance of all applications based on martensitic transformations.

Recycling is part of the circular economy contributing to the sustainable and secure supply of raw materials. Most consumer products, from cars to domestic appliances, consist of multi-material structures which form complex wastes after their use phase. Therefore and with the focus on sustainability, the design decisions of product manufacturers have a significant influence on recyclability. So far, methods exist to evaluate the performance of metallurgical recycling systems through process simulation. However, there is a lack of methods to estimate the impact of design decisions on the liberation behaviour during crushing.
In a case study, a large-scale recycling campaign examined 100 refrigerators from the household sector in a commercial primary waste treatment facility. Initially, the fridges were analysed regarding e.g. initial mass, size, outer appearance, and manufacturer in order to be categorized into three fractions. Then the conventional pre-treatment steps were documented such as depollution, removal of glass shelfs, printed circuit boards and compressors. Finally, the mechanical processing started beginning with a two-stage crushing and subsequent separation in an air classifier (density sorting), magnetic and eddy current separator.
The main products of the mechanical processing are a PU rich, a ferrous, a non-ferrous and a plastics fraction. The last three of those were analysed in more detail in order to quantify the degree of liberation as well as the separation efficiency. Liberation was evaluated at particle level in terms of unliberated connections between different materials (material mixed particles) as well as connections of different components consisting of the same material (component mixed particles). This data allows deducing the liberation efficiency, which affects sorting and final product qualities.
Furthermore, the liberation efficiency of different connection types (e.g. screwing, gluing, coating, snap-fitting) was identified. Coupling these insights with a material compatibility assessment for subsequent recovery processes, design recommendations have been derived for liberation-oriented choice of connection types and specific material combinations. For example, steel in the PU rich fraction causes problems during conveying and pelletizing and is therefore regarded as hazardous pollutant for subsequent processing. In contrast to that, aluminium in the ferrous fraction deceases slightly the product quality but can be removed easily during subsequent metallurgical refinement.
As an ongoing research topic, finite element method (FEM) simulations supplement these experimental investigations to enable the analysis of various multi-material designs. In these simulations, composites of metal and fibre-reinforced plastics are modelled in a crushing process and compared to laboratory scale experiments (figure 2) regarding their liberation potential during crushing and their overall recyclability. In the future, this methodical approach will allow assessing the effects of the product design on recyclability already in the design stage assisting the development of recycling-friendly products.

Martensitic transformations are important for many materials exhibiting magneto-, elasto- and barcaloric effects and
often the functional properties benefit from additional magnetic transformations. For caloric applications, thin films
are of particular interest due to their fast heat exchange, which promises a high cooling power. In particular epitaxial
films are a model system to understand the formation of the martensitic microstructure.[1] However, commonly
transformations from austenite to martensite only occur during cooling. The recent observation of a so-called reentrant
transformation obtained much interest, as an additional transformation from martensite to austenite was observed
during further cooling.[2,3] A reentrant transition increases both, the number of new physical effects and the possible
applications. However, reports are currently very few and only on bulk materials. Will this phenomenon occur also in
thin films? Will the martensitic transformation and microstructure differ when induced by heating or cooling? Also
for caloric applications, reentrant martensite is interesting as it may enable bidirectional caloric effects driven by
deformation and recovery of the ferromagnetic shape memory alloys (FSMA) through both, heating and cooling.
As a model system, epitaxial Co-Cr-Ga-Si ferromagnetic shape memory thin films were grown by DC magnetron
sputtering. To obtain epitaxial growth, films were deposited on different substrates as well as orientations. We identify
MgO(100) as the optimum substrate. Films were grown at different deposition temperatures and the influence of an
additional postannealing process was examined to understand the influence on elemental composition, structure,
microstructure and the transformation behavior. As a kind of summary, Fig.1-a depicts a phase diagram of all samples
prepared. Under optimum conditions, we obtain epitaxial growth, as evident from pole figure measurements of an
austenitic film (Fig. 1-b). When films are subjected to an additional heat treatment at 800°C, films are martensitic at
room temperature, which is evident the peak splitting in pole figure measurements (Fig. 2-a) and agree well with pole
figures calculated by the phenomenological theory of martensite with a c/a ratio of 1.37 (Fig. 2-b). Furthermore, the
microstructure becomes granular and twin boundaries become visible. Though annealing improves the martensitic
transformation, we observe a degradation of the ferromagnetic transition. To sum up, we could demonstrate epitaxial
growth of Co-Cr-Ga-Si films, which are martensitic and ferromagnetic at room temperature. This is a key step to
utilize the additional possibilities of reentrant martensite also for thin films.

Zyklotrone bilden als Ressource medizinischer Radionuklide eine zentrale Infrastruktur für die Entwicklung neuer und die Produktion klinisch etablierter Radiotracer zur molekularen Hybridbildgebung. Da die letzte umfassende Veröffentlichung zu Zyklotronen ca. 15 Jahre alt ist, wurde eine Statuserhebung zu den für die Nuklearmedizin und Radiopharmazie in Deutschland, Österreich und der Schweiz (D-A-CH-Länder) betriebenen Zyklotronen angestrebt.

The performance gap between CPU and memory widens continuously. Choosing the best memory layout for each hardware architecture is increasingly important as more and more programs become memory bound. For portable codes that run across heterogeneous hardware architectures, the choice of the memory layout for data structures is ideally decoupled from the rest of a program. This can be accomplished via a zero-runtime-overhead abstraction layer, underneath which memory layouts can be freely exchanged.
We present the Low-Level Abstraction of Memory Access (LLAMA), a C++ library that provides such a data structure abstraction layer with example implementations for multidimensional arrays of nested, structured data. LLAMA provides fully C++ compliant methods for defining and switching custom memory layouts for user-defined data types. The library is extensible with third-party allocators.
Providing two close-to-life examples, we show that the LLAMA-generated AoS (Array of Structs) and SoA (Struct of Arrays) layouts produce identical code with the same performance characteristics as manually written data structures. Integrations into the SPEC CPU® lbm benchmark and the particle-in-cell simulation PIConGPU demonstrate LLAMA's abilities in real-world applications. LLAMA's layout-aware copy routines can significantly speed up transfer and reshuffling of data between layouts compared with naive element-wise copying.
LLAMA provides a novel tool for the development of high-performance C++ applications in a heterogeneous environment.

Classical Random Neural Networks (RNNs) have demonstrated effective applications in decision making, signal processing, and image recognition tasks. However, their implementation has been limited to deterministic digital systems that output probability distributions in lieu of stochastic behaviors of random spiking signals. We introduce the novel class of supervised Random Quantum Neural Networks (RQNNs) with a robust training strategy to better exploit the random nature of the spiking RNN. The proposed RQNN employs hybrid classical-quantum algorithms with superposition state and amplitude encoding features, inspired by quantum information theory and the brain’s spatial-temporal stochastic spiking property of neuron information encoding. We have extensively validated our proposed RQNN model, relying on hybrid classical-quantum algorithms via the PennyLane Quantum simulator with a limited number of qubits. Experiments on the MNIST, FashionMNIST, and KMNIST datasets demonstrate that the proposed RQNN model achieves an average classification accuracy of 94.9%. Additionally, the experimental findings illustrate the proposed RQNN’s effectiveness and resilience in noisy settings, with enhanced image classification accuracy when compared to the classical counterparts (RNNs), classical Spiking Neural Networks (SNNs), and the classical convolutional neural network (AlexNet). Furthermore, the RQNN can deal with noise, which is useful for various applications, including computer vision in NISQ devices. The PyTorch code is made available on GitHub to reproduce the results reported in this manuscript.