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Automating Lifecycle Compliance: A Continuous Assessment Framework for High-Risk and GPAI Obligations in the EU AI Act
No full text279301The EU AI Act specifies legal obligations for both providers of high-risk AI systems and providers of general-purpose AI (GPAI) models with systemic risk potential. Satisfying these obligations at scale requires an automated framework that can operationalize the Act’s key operational compliance clauses, risk management (Art. 9), technical documentation (Art. 11), quality management (Art. 17), conformity assessment (Art. 43), EU Declaration of Conformity (Art. 47), and post-market monitoring (Art. 72), as well as capability monitoring and transparency duties for GPAI providers (Arts. 53 & 55). We introduce Continuous Auditing-Based Conformity Assessment (CABCA), a framework that translates legal requirements into actionable, machine-readable metrics and continuously updated conformity declarations. CABCA first uses a Scoping process to define a formal Conformity Specification, which is then translated into a machine-readable Operationalization Specification containing quality dimensions, traceable risks, measurable controls, and automated evaluation pipelines. These components collectively support the assessment of both system-level risks in high-risk domains and model-level risks from GPAI deployment.
Once configured, the CABCA pipeline (i) gathers operational and behavioral data, (ii) evaluates capability and risk thresholds against declared objectives, and (iii) produces a continuously valid declaration of conformity or model compliance statement.
By integrating system-level conformity obligations and GPAI-specific oversight requirements into a single, continuous workflow, CABCA provides a scalable path to bring and keep high-risk AI systems and GPAI models into maintaining compliance throughout the model lifecycle
EUV ptychography: Material-Specific Imaging at the Nanoscale
No full textEUV ptychography combines high resolution, strong material contrast, reasonable penetration depth, and easy sample preparation. It thus has the potential to bridge the gap between visible light and electron microscopy. In this contribution, we present recent results on table-top ptychographic EUV microscopy. The experimental setup relies on a high photon flux 13.5 nm wavelength high-order harmonic source [1]. A simple amplitude mask upstream of the sample tailors the illumination. The sample is scanned by piezo-driven stages. Finally, far-field diffraction patterns are recorded by an EUV detector and fed into a ptychographic iterative engine to retrieve both the illumination and the sample transmission in amplitude and phase. The resolution of the EUV microscope (16 nm) was characterized using a Siemens star test sample. In the next step, a thin lamella of an integrated circuit was investigated. The resulting EUV images exhibit a rich diversity in amplitude and phase. We analyzed that the relative amplitude precision is better than 4% and the absolute phase precision as good as ~ 20 mrad. In this way, the microscope provides excellent input data for further analysis of the material composition. For this purpose, the projected scattering quotient is calculated from the reconstructed phase and amplitude and compared to tabulated material parameters. Here, materials like Al, Si3N4, and SiO2 were determined with high sensitivity. Finally, biological samples, namely germlings of the filamentous fungus Aspergillus nidulans were investigated. A similar scattering quotient analysis allowed us to clearly distinguish regions with low- and high lipid and phospholipid concentrations
Demonstration of E/D-Mode Logic Circuits in a Four-Pole 20-nm InGaAs HEMT-on-Silicon Technology using Back-Gate Biasing
No full textWe present enhancement- and depletion-mode digital logic gates and circuits with back-gate biasing in a Four-pole high-electron-mobility transistor on Silicon technology. This work uses a 20-nm gate-length InGaAs HEMT-on-Si with the option to place an electron-beam-lithography defined back-gate below the InGaAs channel by wafer bonding. By applying back-gate bias, the threshold voltage is modulated to convert normally depletion-mode devices into enhancement-mode devices, without altering the physical structure or processing steps. The back-gated RF transistors are used directly to implement digital logic gates such as NOT, NAND, and NOR, as well as a D-LATCH circuit, and are demonstrated using the E/D logic approach. Additionally, the effect of back-gate biasing on the power consumption of logic gates is analyzed. The proposed circuits provide the opportunity to integrate logic components with state-of-the-art RF circuits monolithically.Online Firs
Metal Binder Jetting - First design guidelines for boreholes and channels Metal Binder Jetting - Erste Konstruktionsempfehlungen für Bohrungen und Kanäle
No full text6166Metal binder jetting - a new additive manufacturing process - allows the production of components with a high degree of complexity. However, differences in the process chain lead to special requirements for component design. The comparatively low strength of the green parts makes it difficult to reliably remove loose powder that sinters together with the component in the further course of the process chain and thus results in a partly irreparable geometric deviation. Corresponding design guidelines are currently only available to a limited extent. The aim of this article is therefore to identify process limits for the reliable design of boreholes and channels.766-
Clinical importance of patient-reported outcome measures in severe asthma: results from U-BIOPRED
No full textRationale: Knowledge about the clinical importance of patient-reported outcome measures (PROMs) in severe asthma is limited. Objectives: To assess whether and to what extent asthma exacerbations affect changes in PROMS over time and asthma-specific PROMs can predict exacerbations in adult patients with severe asthma in usual care. Methods: Data of 421 patients with severe asthma (62% female; mean age 51.9 ± 13.4 years; mean FEV1 67.5 ± 21.3%pred) from the U-BIOPRED cohort were analyzed. The included PROMs were: Asthma Control Questionnaire (ACQ5); Asthma Quality of Life Questionnaire (AQLQ); Hospital Anxiety and Depression scale (HADS); Epworth Sleepiness Scale (ESS); Medication Adherence Report Scale (MARS); Sino-Nasal Outcomes Test (SNOT20). Participants were assessed at baseline and after 12–18 months of usual care. Results: PROMs showed very weak to weak correlations with clinical characteristics such as age, body mass index, FEV1, FeNO and eosinophilic cell count. Patients presenting no exacerbations during follow-up showed a statistically significant improvement in all PROMs (except for MARS), whereas individuals experiencing > 2 exacerbations showed a deterioration. Baseline ACQ5 was a predictor of exacerbations with an AUC of 0.590 (95%CI 0.514–0.666). Conclusions: The association of PROMs with clinical measures was poor in severe asthmatics. Moreover, PROMs were prone to changes in usual care, with exacerbations playing a key role. PROMs need to be systematically evaluated in severe asthma to improve clinical care based on specific patient’s needs.22
Evaluating the Effectiveness of Google Fact Check Explorer API for Automated Systematic Fact-Checking
No full textA T-Matrix Based Plant Stem Model for Inverse Scattering Applications
No full textAn efficient method to calculate the azimuthal monostatic radar cross section (RCS) of a plant stem is proposed. The method is based on the recursive aggregated centered T-matrix algorithm (RACTMA) which allows to efficiently calculate the T-matrix of a cluster of scatterers mimicking the internal structure of the plant stem. Due to the high efficiency of the method, it is suitable for the inverse scattering analysis to determine geometrical and material parameters of the internal structure of a plant stem. The method's efficiency and accuracy are demonstrated by the retrieval of unknown geometrical and material parameters, influenced by fabrication tolerances, from monostatic RCS measurements of a 3D-printed mockup of a plant stem. The measurement is conducted for TM polarization at frequencies ranging from 110 GHz to 170 GHz
Tailored strategies for improved control of CAR-T cells in multiple myeloma
No full textRecent advances in chimeric antigen receptor (CAR) T cell therapy have transformed the treatment landscape of multiple myeloma, yet almost all patients ultimately relapse. Chromosomal 1q gains are associated with a higher risk of disease progression and poor prognosis, suggesting that CAR-T targeting of chromosome 1–encoded antigens, such as SLAMF7, may be particularly relevant in advanced disease. However, novel CAR targets raise the risk of on-target, off-tumor toxicities, underscoring the need for controllable CAR-T systems. We systematically assessed pharmacologic and antibody-based strategies to modulate CD19- and SLAMF7-directed CAR-T cells. Tyrosine-kinase inhibitor dasatinib rapidly and reversibly inhibited CAR-T activation, serving as an efficient "on/off" switch with the limitation of also inhibiting unmodified T cells. To surpass this issue, we used antibody-dependent cell cytotoxicity to inhibit CAR-T cells. However, conditioning with fludarabine/cyclophosphamide profoundly depletes NK cells, limiting antibody-dependent CAR-T clearance in patients. Moreover, as NK cells express SLAMF7, they are susceptible to fratricidal cytotoxicity by SLAMF7 CAR-T cells, further reducing this potential off-switch mechanism. To bypass this immune effector cell dependence, we developed a novel strategy using antibody–drug conjugates (ADCs). In this work, we demonstrate that the BCMA-targeting ADC belantamab-mafodotin selectively eliminates BCMA co-expressing CAR-T cells without affecting unmodified T cells. These findings suggest ADCs as a potent, effector cell-independent safety mechanism for CAR-T therapies, potentially enhancing controllability and safety in future clinical applications.1
Uptake and Cellular Effects of Polymethylmethacrylate on Human Cell Lines
No full text205216The usage of plastic and its decomposition products leads to their ubiquitous distribution, resulting in their uptake by all living beings, including humans. Polymethylmethacrylate (PMMA) is known as a biocompatible polymer and is used widely in medicine and dentistry, although recent findings have shown its induction of oxidative stress within cells. Worryingly, hardly any data exist investigating the uptake of PMMA particles by cells, the potential effects of these particles on cells and cell signaling pathways and their contributing factors. We assessed the uptake of PMMA beads via confocal microscopy after their incubation with HEK293, A549 and MRC5 cells. Through cell staining, we localized multiple PMMA beads within the cytosol of cells. No alterations regarding cell growth, cell morphology or cell division were found, implying no short-term toxicity towards human cells. Using a cAMP response element binding protein (CREB)-mediated reporter assay, we assessed whether internalized PMMA nanobeads alter cell signaling pathways after stimulation of the cells. CREB was chosen as a well-described transcription factor involved in various cellular processes. Our data led to the assumption that PMMA nano- and microbeads are internalized via endocytosis and end up in lysosomes within the cell cytosol. We concluded that differences regarding the surface composition of the PMMA nanobeads affect their potential to alter cell signaling. These findings emphasize the key role the surface composition plays regarding microplastics and their risks for human health, whereas the usage of medical-grade PMMA remains safe.3
Lessons Learned during Preparation and Execution of the Satellite Operations of the E-band Technology Demonstration CubeSat EIVE
No full text213222The 6U CubeSat Exploratory In-orbit Verification of an E-band Link (EIVE) is the latest satellite of the University of Stuttgart. It was developed together with partners in industry and research since 2019 and was launched on June 12, 2023. EIVE’s main mission objective is the verification of an E-band downlink to Earth and is therefore equipped with a 71-76 GHz payload transmitter. The satellite is operated from the mission control centre at the University of Stuttgart’s Institute of Space Systems (IRS). Operations are largely carried out utilising the S- and E-band Ground Stations (GSs) at the University of Stuttgart and its newly developed Multi-Mission Operations System (MMOS) software. Three additional German Space Agency (DLR) GSs were used during the first two weeks to increase contact times. This paper discusses the EIVE operations during the pre-launch preparation and validation phases. Operational experiences during operator training and the in orbit phases are shared and discussed