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Die digitale Transformation stellt uns beim DRK Neuss vor große Herausforderungen. Auf der einen Seite möchten wir in bewährten Strukturen weiterarbeiten, auf der anderen Seite verlangen Kunden, Mitglieder und Mitarbeitende den Schritt zu einem modernen Dienstleistungsverband. Daher hat der Vorstand des DRK Neuss Anfang 2020 eine Digitalstrategie aufgesetzt. Ein zentrales Element ist die „DRK Neuss App“.

Background RO7122290 (RO) is a potent next generation 4-1BB agonist simultaneously targeting fibroblast activation protein (FAP). FAP is highly expressed on cancer-associated fibroblasts in many solid tumors, while expression in healthy tissue is low. 4 1BB stimulation via FAP mediated cross linking augments the cytotoxicity, proliferation, and longevity of immune effector cells in FAP-positive tumors. RO was labelled with Zirconium-89 (89Zr) to visualize FAP-dependent tumor accumulation and assess the biodistribution in patients (pts) after successful proof of principle of 89Zr-based PET in preclinical pilot studies. Methods Pts with advanced and/or metastatic solid tumors were eligible for this sub-study of an ongoing Phase 1/1b trial (EUDRACT 2017-003961-83). RO was administered intravenously once at a total dose of 5, 45, 200 or 500 mg consisting of RO (cold) + 5 mg 89Zr-RO (hot, 37.0 [± 3.4] MBq).Up to three 89Zr-PET scans were performed over a period of nine days followed by a single tumor biopsy before pts could switch to Part A (single agent) and subsequently to Part B (combination with atezolizumab) of the main study to continue treatment. Tracer uptake was calculated as peak standardized uptake value (SUVPeak) of the lesion with the highest uptake. Results 14 pts were exposed to a total dose of 5, 45, 200 (all n=3) or 500 mg (n=5); median age was 60 years (range 26–74) with seven male and female pts each. Primary tumor sites included colon (n=4), lung (n=3), thymus (n=2), anus (n=1), breast (n=1), bile duct (n=1), pleura (n=1), and uvea (n=1). In healthy tissues, uptake of 89Zr-RO was predominantly observed in the liver and spleen across all doses and in non-malignant lymph nodes in 2/3 patients at 5 mg. Consistent with the target expression, tracer uptake was detected in FAP-positive scarring tissue and tissues with ongoing remodeling. Intra-tumoral accumulation of 89Zr-RO was observed at all doses. 96 hours p.i., SUVPeak values were 12.1 [± 4.1], 10.0 [± 4.9], and 7.0 [± 3.7] for the 5, 45 and 200 mg cohorts, respectively, while SUVPeak for the 500 mg cohort was even lower at 4.9 [± 0.5]. Conclusions 89Zr-PET confirmed tumor-specific uptake and expected biodistribution pattern of 89Zr-RO. The decrease in SUV with increasing doses suggest that more cold antibodies saturated FAP binding sites in the tumor. 89Zr-PET results supported together with clinical PK, PD, safety and response data the selection of the recommended phase 2 dose and schedule of RO in combination with atezolizumab.

Nature photonics 14(6), 391 - 397 (2020). doi:10.1038/s41566-020-0607-z, The European XFEL is a hard X-ray free-electron laser (FEL) based on a high-electron-energy superconducting linear accelerator. The superconducting technology allows for the acceleration of many electron bunches within one radio-frequency pulse of the accelerating voltage and, in turn, for the generation of a large number of hard X-ray pulses. We report on the performance of the European XFEL accelerator with up to 5,000 electron bunches per second and demonstrating a full energy of 17.5 GeV. Feedback mechanisms enable stabilization of the electron beam delivery at the FEL undulator in space and time. The measured FEL gain curve at 9.3 keV is in good agreement with predictions for saturated FEL radiation. Hard X-ray lasing was achieved between 7 keV and 14 keV with pulse energies of up to 2.0 mJ. Using the high repetition rate, an FEL beam with 6 W average power was created., Published by Nature Publ. Group, London [u.a.]

Accumulating evidence suggests that intranasal oxytocin (OXT; 24 IU) reduces amygdala responses to fear-related stimuli in men, while exerting inverse effects in women. However, OXT enhances activity of the brain reward system in both sexes. Importantly, a crucial and still open question is whether there are sex-specific dose-response relationships for the amygdala and striatal regions. To address this question, a total of 90 healthy women participated in a double-blind, placebo-controlled crossover functional magnetic resonance imaging (fMRI) study and the results were compared with our previous findings from men. Participants were randomly assigned to three doses of OXT (6 IU, 12 IU, and 24 IU) and completed an emotional face recognition task including fearful and happy faces of varying emotional intensities. Across doses, OXT enhanced amygdala reactivity to low fearful faces compared to placebo and increased responses to happy faces in the dorsal striatum in women. While treatment effects on amygdala reactivity were evident at each given dose, the OXT effect on striatal responses to social stimuli was more pronounced with higher doses, but this dose-dependent effect did not survive correction for multiple comparisons. Importantly, OXT effects on amygdala and striatal activation significantly differed between sexes and striatal baseline sexual-dimorphic response patterns were diminished after administration of OXT. Our findings suggest that OXT increases the salience of social signals by strengthening the sensitivity for these signals in the amygdala and in the striatum in women, while OXT may primarily induce anxiolysis by reducing amygdala responses in men.

We present a new generation of photoconductive (PC) terahertz (THz) near-field probes based on freestanding Beryllium-doped low-temperature-grown InGaAs/InAlAs cantilevers. The PC probes are compatible to optical gating with a femtosecond laser having a center wavelength of 1550 nm. Therefore, they are well suited for a cost-efficient direct integration with fiber-coupled THz time-domain spectroscopy (TDS) systems. The photoconductor material features electron lifetimes of 500 fs allowing for broadband detection up to 2 THz, which is comparable to existing LT-GaAs-based near-field detectors, which require 800-nm wavelength excitation. We demonstrate the detector operation in a state-of-the-art fiber-based TDS system with fast and coherent data acquisition and show obtained sheet-resistance mappings of conductive thin-films featuring subwavelength resolution.

Optical inspection of the inner surface of superconducting resonators was established during European XFEL cavity production by usage of the so called OBACHT optical inspection. In addition to the surface inspection by OBACHT a new optical inspection system with integrated high resolution camera is set up at DESY. It allows inspection of multi-cell resonators as well as gun cavity resonators with only single side accessibility to the inner surface. A prototype was commissioned and optical inspections were done with OBACHT and the new system in parallel. Two SRF gun cavities were inspected by this optical system and origin of limitations of the resonators were identified., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

Radio-frequency cavities made of bulk niobium are one of the components used in modern particle accelerators. The mechanical stability is an important aspect of cavity design, which typically relies on finite-element analysis simulations using material properties from tensile tests on sample. This contribution presents the results of strain and resonant frequency measurements as a function of a uniform pressure up to 620 kPa, applied to single-cell niobium cavities with different crystallographic structure, purity and treatments. In addition, burst tests of high-purity multi-cell cavities with different crystallographic structures have been conducted up to the tensile strength of the material. Finite-element analysis of the single-cell cavity geometry is in good agreement with the observed behavior in the elastic regime assuming a Young’s modulus value of 88.5 GPa and a Poisson’s ratio of 0.4, regardless of crystallographic structure, purity or treatment. However, the measured yield strength and tensile strength depend on crystallographic structure, material purity and treatment. In particular, the results from this study show that the mechanical properties of niobium cavities made from ingot material with large crystals are comparable to those of cavities made of fine-grain niobium.

Ligas de níquel têm atualmente uma vasta gama de aplicações, sendo a agressividade do meio e as elevadas temperaturas que estas ligas suportam, um diferencial excepcional. A liga UNS N07090, objeto deste trabalho, encontra aplicações muito diversas, entre elas turbocompressores, sistemas de exaustão e de pós-tratamento de motores a diesel. Nestas aplicações a liga está exposta a gases, que ao condensarem formam ácido sulfúrico (H2SO4). Torna-se, assim, importante, o conhecimento da resistência à corrosão da liga nesse meio. O presente trabalho tem como objetivo caracterizar o comportamento eletroquímico da liga através de curvas de polarização potenciodinâmica em diferentes concentrações de ácido sulfúrico. Observou-se que quanto maior a concentração de ácido, maior é a corrosão da liga. Este fato pode ser discutido pela adsorção do íon sulfato (SO42-), que prejudica tanto a formação quanto a cinética de crescimento da película passiva do níquel. Em contrapartida, a presença de Cr na liga UNS N07090 apresentou um benefício sobre a resistência à corrosão desta muito acima do esperado, influenciando de forma direta as curvas de polarização da liga e mantendo-a em condição de elevada resistência à corrosão em detrimento do pior desempenho observado em outros elementos pertecentes à liga, como Co, Al e Ti. Tempos de imersão de 24h em ácido sulfúrico elevam discretamente os parâmetros de corrosão da liga, mantendo-os, no entanto em patamares bastante baixos, permitindo finalmente concluir que a liga UNS N07090, quando exposta a concentrações que variam de 1M a 4M H2SO4, a 25°C, apresenta boa resistência à corrosão e que esta não se altera com o tempo de exposição. A análise dos resultados mostrou que o processo corrosivo é controlado por reações catódicas de sulfato e hidrogênio, as quais podem ter diferentes contribuições dependendo da concentração do ácido e do tempo de imersão da liga UNS N07090 no meio corrosivo. Nickel alloys have a wide range of application nowadays due to their excellent resistance to aggressive media and high temperatures. UNS N07090, the nickel alloy studied herein, is used for turbochargers, exhaust and after treatment systems of diesel engines. These applications expose the alloy to hot gases, which condensate forming sulfuric acid (H2SO4). It is thus important to know the corrosion resistance of the alloy in this media. The goal of this work is the characterization of the electrochemical behaviour of UNS N07090 alloy through potentiodynamic polarization curves in different sulfuric acid concentrations. On the one hand, higher acid concentrations were noticed to lead to higher corrosion of the alloy. This phenomenon can be discussed by sulfate (SO42-) adsorption, which negatively influences not only the formation but also the growth of the passive film on nickel. On the other hand, the presence of Cr in UNS N07090 composition, improves the corrosion resistance of the alloy far more than expected, directly affecting the shape of the polarization curves of the alloy, placing it in a condition of high corrosion resistance despite the worst performance shown by the other elements present in the chemical composition of the alloy, such as Co, Al and Ti. 24h immersion periods in sulfuric acid slightly raise corrosion parameters of UNS N07090 alloy, but still ranking the alloy in very good corrosion resistance. Finally, it can be concluded that UNS N07090 alloy exposed to 1M to 4M H2SO4 at 25°C presents good corrosion resistance and that this is not affected by longer immersion periods. The results showed that the corrosion process of alloy UNS N07090 is controlled by sulfate and hidrogen cathodic reactions, which have stronger or weaker contribution depending on acid concentration and immersion time on the corrosive media.

18th International Conference on RF Superconductivity, Lanzhou, China, 17 Jul 2017 - 21 Jul 2017; Geneva : Jacow, 1-4 (2017)., Optical inspection of the inner surface of superconducting resonators was established during European XFEL cavity production by usage of the so called OBACHT optical inspection [1]. In addition to the surface inspection by OBACHT a new optical inspection system with integrated high resolution camera is set up at DESY. It allows inspection of multi-cell resonators aswell as gun cavity resonators with only single side accessibility to the inner surface. A prototype was commissioned and optical inspections were done with OBACHT and the new system in parallel. Two SRF gun cavities were inspected by this optical system and origin f limitations of the resonators were identified., Published by Jacow, Geneva

TTC Meeting February 2017, East Lansing, Michigan State University, USA, 21 Feb 2017 - 24 Feb 2017

All components installed to the European XFEL cavity string modules underwent an intensive inspection and quality control before acceptance for installation to cavities or modules. Even though some RF feed throughs for HOM coupler- and Pick Up antennas showed leaks at the ceramic insulation after module test at 2 K. Due to time restriction and continuity of production the exchange of these parts needed to be done without reentering the cleanroom. Successful repair of these modules took place by setting up a local cleanroom onto the cavity string. In collaboration with Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a cavity string for the ELBE project was assembled at DESY and transported to HZDR for installation to the vacuum vessel. A spare module with 3.9 GHz Resonators for the European XFEL was set up at DESY and will be tested and qualified for the European XFEL. Due to delay in delivery of the power couplers, four power couplers were installed after string assembly., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

Helmholtz-Zentrum Berlin (HZB) is currently designing and building an high average current all superconducting CW driven ERL as a prototype to demonstrate low normalized beam emittance of 1 mm·mrad at 100mA and short pulses of about 2 ps. In order to achieve these demanding goals HZB started a staged program for developing this class of required high current, high brightness SRF electron sources. In this contribution we will present the current status of the module assembly and testing of the prototype SRF photo-injector cavity cold string. The steps taken to install the cathode insert system with the cavity in the cleanroom and the following horizontal test of the cold string as final acceptance test prior installation into its cryostat are shown. First beam in a dedicated diagnostics teststand called Gunlab are planned for this winter., Proceedings of the 28th Linear Accelerator Conf., LINAC2016, East Lansing, MI, USA

At DESY activities on surface treatment of superconducting RF gun cavity resonators at 1.3 GHz are ongoing. Due to the small opening on the endplate for insertion of cathodes, no reasonable acid flow can be realized with the existing set up for horizontal electro polishing. To benefit from electro polishing of Niobium surfaces, an adapter to the existing horizontal electro polishing bench at DESY was set up and is in operation now. Vertical EP was applied on 1.3 GHz SRF gun resonators with 1.6 and 3.5 cell geometry. Work flow, process conditions as well as test results of gun cavities treated so far at DESY are described., Proceedings of the 18th Int. Conf. on RF Superconductivity, SRF2017, Lanzhou, China

Physical review accelerators and beams 20(4), 042005 (2017). doi:10.1103/PhysRevAccelBeams.20.042005, A full test of the cavity package concept under realistic operating condition was a necessary step before the assembly of the European XFEL (EXFEL) 3.9 GHz superconducting system and its installation in the accelerator. One cavity, equipped with magnetic shielding, power coupler and frequency tuner has been tested in a specially designed single cavity cryostat in one of the test benches of the DESY Accelerator Module Test Facility (AMTF). The cavity was operated at high pulsed power up to an accelerating field of 24 MV/m, above the quench accelerating field of 21 MV/m achieved during the continuous wave (CW) vertical qualification test and with a large margin with respect to the EXFEL maximum operating specification of 15 MV/m for the 3.9 GHz system. All subsystems under test—coupler, tuner, waveguide tuners, low level radio-frequency (LLRF) system—were qualified to their design performances., Published by American Physical Society, College Park, MD

Optical data links are the backbone of today’s telecommunication infrastructure. The integration of electronic and optic components on one chip is one of the most attractive routes to further increase the system performance. Here, we present the fabrication of photodetectors based on CVD-grown graphene on silicon photonic waveguides. The devices operate bias-free in the C-band at 1550 nm and show an extrinsic −3 dB bandwidth of 41 GHz. We demonstrate that these detectors work at data rates up to 50 GBit/s with excellent signal integrity.

Helmholtz Zentrum Berlin HZB is currently designing and building an high average current all superconducting CW driven ERL as a prototype to demonstrate low normalized beam emittance of 1 mm mrad at 100 mA and short pulses of about 2 ps. In order to achieve these demanding goals HZB started a staged program for developing this class of required high current, high brightness SRF electron sources. In this contribution we will present the current status of the module assembly and testing of the prototype SRF photoinjector cavity cold string. The steps taken to install the cathode insert system with the cavity in the clean room and the following horizontal test of the cold string as final acceptance test prior installation into its cryostat are shown. First beam in a dedicated diagnostics test stand called Gunlab are planned for this winter

International audience

We present contact-free THz near-field measurements at large-area graphene covered by an ion gel top-gate. In dependence of the gate-voltage, we map the THz near-field transmission amplitude and the resulting sheet resistance distribution across the graphene layer. High-resolution access to the local charge carrier properties of the buried graphene enables the visualization of inhomogeneity and defects on a microscopic scale and the time-dependent evolution of the ion gel based doping process.

We present experimental results revealing new details of the resonant electromagnetic behavior of a single TiO 2 microsphere in the THz frequency range. In order to reduce background signal contributions and to increase the excitation efficiency, measurements are done using aperture-less photoconductive near-field microprobes in parallel and crossed alignment to the polarization of a free-space radiation pulse or a guided pulse on a coplanar stripline — both applied alternatively for sample excitation.

We have performed far-field extinction measurements and near electric field measurements on gold bowtie antennas resonant at THz frequencies. These measurements show a very large shift between the resonant frequencies of the near-field and the far-field spectra. We use the established damped-driven harmonic oscillator model for resonators to model the far-field response of the antennas from the near-field spectrum and show that there is a large discrepancy between the predicted and measured far-field response. We were able to explain this discrepancy by improving the oscillator model with a Fano model. This large shift makes the prediction of the near-field response of resonant structures at THz frequencies very imprecise, provided that only information of the far-field response is available and establishes the necessity of measuring near fields for a correct and accurate characterization of these structures.

Physical review accelerators and beams 19(9), 092001(2016). doi:10.1103/PhysRevAccelBeams.19.092001, The production of over 800 1.3-GHz superconducting (SC) cavities for the European X-ray Free Electron Laser (EXFEL), the largest in the history of cavity fabrication, has now been successfully completed. In the past, manufacturing of SC resonators was only partly industrialized; the main challenge for the EXFEL production was transferring the high-performance surface treatment to industry. The production was shared by the two companies RI Research Instruments GmbH (RI) and Ettore Zanon S.p.A. (EZ) on the principle of “build to print”. DESY provided the high-purity niobium and NbTi for the resonators. Conformity with the European Pressure Equipment Directive (PED) was developed together with the contracted notified body TUEV NORD. New or upgraded infrastructure has been established at both companies. Series production and delivery of fully-equipped cavities ready for cold rf testing was started in December 2012, and finished in December 2015. More than half the cavities delivered to DESY as specified (referred to “as received”) fulfilled the EXFEL specification. Further improvement of low-performing cavities was achieved by supplementary surface treatment at DESY or at the companies. The final achieved average gradient exceeded the EXFEL specification by approximately 25%. In the following paper, experience with the 1.3-GHz cavity production for EXFEL is reported and the main lessons learned are discussed., Published by American Physical Society, College Park, MD

We present a new generation of photoconductive (PC) terahertz (THz) near-field probes based on freestanding Beryllium-doped low-temperature-grown InGaAs/InAlAs cantilevers. The PC probes are compatible to optical gating with a femtosecond laser having a center wavelength of 1550 nm. Therefore, they are well suited for a cost-efficient direct integration with fiber-coupled THz time-domain spectroscopy (TDS) systems. The photoconductor material features electron lifetimes of 500 fs allowing for broadband detection up to 2 THz, which is comparable to existing LT-GaAs-based near-field detectors, which require 800-nm wavelength excitation. We demonstrate the detector operation in a state-of-the-art fiber-based TDS system with fast and coherent data acquisition and show obtained sheet-resistance mappings of conductive thin-films featuring subwavelength resolution.