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PSA Secretion from Single Circulating Tumor Cells of Metastatic Castration-Naïve Prostate Cancer Patients
No full textPSA is the most common biomarker used in the screening and monitoring of prostate cancer. However, changes in PSA do not always reflect disease dynamics in every patient, and antihormonal agents may modulate its levels without significant antitumor effects. Changes in circulating tumor cells (CTC) have been described as a more objective measure of treatment response. Differences between PSA and CTC may be explained by heterogeneity in tumor cells producing PSA. To explore this, we measured the PSA secretion from a single CTC to gain insights into the PSA secretion heterogeneity between tumor cells. CTCs were enriched using EpCAM-based immunomagnetic enrichment in diagnostic leukapheresis of 18 patients with metastatic castration-na¨ıve prostate cancer (mCNPC) not pretreated with any therapy, including androgen deprivation therapy. Calcein+ CD45 cells were sorted by flow cytometry and deposited as single cells on a nanowell array to measure the PSA secretion after 24 hours. In nine of 18 patients, PSA secretion was detectable and observed from both prostate-specific membrane antigen–positive and prostate-specific membrane antigen–negative CTCs. In these patients, 29% to 100% (mean, 52; median, 47) of CTCs secreted PSA, with average PSA secretion levels ranging from 4 to 11.68 pg/cell (mean, 6.38 ± 2.29; median, 6.05). Notably, a strong heterogeneity in PSA secretion was observed within each patient. Our study demonstrates that CTC in mCNPC, even before therapy, produces varying amounts of PSA and often no PSA. These findings may explain the shortcomings of PSA as a biomarker for therapy response.</p
Rayleigh wave induced cavitation bubble structures
No full textA localized energy deposition in a thin layer of liquid between two solid glass plates excites waves in the liquid, solids, and their interfaces. Of particular interest is an elastic surface wave (Rayleigh wave) on the liquid–solid interface that travels faster than the shock wave in the liquid. The surface deformation caused by the Rayleigh wave expands the layer of liquid, thereby locally reducing the pressure below the cavitation threshold. The created tension nucleates many cavitation bubbles, which later collapse due to the passage of the trailing shock wave in the liquid. Interestingly, the bubbles are not arranged homogeneously but on concentric rings centered on the location of the energy deposition. We explain the formation of the concentric rings with the interaction between neighboring bubbles. The fluid–structure interaction is modeled with a coupled finite volume solver that couples a multi-phase compressible fluid region (water and bubble gas) with an elastic solid (glass). We find that the nucleation of bubbles in such a geometry relaxes the tension in their immediate vicinity and thereby suppresses the growth of neighboring bubble nuclei. This idea is confirmed by a Rayleigh–Plesset model of a bubble driven by a far-field pressure obtained from the finite volume simulation. The observed ring patterns are thus the result of the successive activation of statistically distributed nucleation sites into explosively expanding cavitation bubbles in an axisymmetric geometry, whose strong interaction on short distances leads to a hindrance of bubble growth in radially distinct regions.</p
Mit KI Unterricht planen:Generative KI als persönlicher Assistent für die Unterrichtsvorbereitung
No full textPreparing lessons is a time-consuming and complex task. It involves combining specialist knowledge with educational concepts in order to create learning environments in which pupils can actively construct knowledge. Creative ideas are also needed to prepare learning content for heterogeneous learning groups.Generative AI (GKI), such as ChatGPT, is increasingly being discussed as a tool that can support this process. This article highlights practical applications and necessary critical skills
The Evolution of the Business Model Canvas for Digital Sustainability
No full textWith the rise of digitalization, traditional business models (BMs) are evolving to incorporate digital technologies. Innovations like the Internet of Things, platforms, and virtual reality are reshaping the business landscape, prompting organizations to integrate digitalization while addressing sustainability. The business model canvas (BMC) has become integral to modern business practices, offering a structured framework for conceptualizing, analyzing, and innovating BMs. Our systematic review of literature on sustainable BMCs and digital BMCs identifies 14 sustainable BMCs and ten digital BMCs, each integrating traditional BMC elements while introducing new components to meet sustainability or digital technology demands. We synthesize insights to develop a novel framework: the sustainable and digital BMC, comprising 18 elements essential for fostering sustainability and leveraging digital technologies in BMs. Additions such as ecosystem, co-creation, and capabilities underscore the importance of collaborative value creation. The differentiation of the value proposition dimension into economic, social, and environmental values aligns business objectives with sustainable development principles. Considerations of social and environmental impacts in the value capture dimension highlight the complexities of digital transformation. The extension of the value delivery dimension to include platform, supply chain, and potential competition reflects the evolving dynamics of digital business ecosystems and competitive landscapes. Our study emphasizes the significance of integrating sustainability and digitalization in contemporary business model innovation efforts, underscoring the need for further research to explore emerging challenges and opportunities in the digital era.</p
Disrupting the browsing experience:impact of sponsored social media content on affective flow without driving engagement
No full textIntroduction: Understanding how emotional experiences shape consumer behavior in digital environments is a central issue in decision-making neuroscience. While social media feeds are saturated with sponsored content, little is known about how such content modulates affective rhythms and influences engagement. Methods: Grounded in decision neuroscience frameworks and affective processing models, this study develops a three-layer analytical model to capture the emotional microstructure of scrolling behavior, conceptualized as the micro-customer journey. Participants navigate a simulated social media feed while responses were recorded via facial expression analysis, skin conductance, and real-time engagement tracking. Results: Browsing was predominantly neutral in affective tone, interrupted by brief spikes in arousal and positive valence. Sponsored content disrupted this baseline neutrality, producing a subtle shift in affective flow without amplifying emotional intensity. Contrary to common assumptions, biometric indicators of emotional arousal and valence did not predict engagement behavior. Discussion: Findings suggest that commercial content influences decision-making not by heightening emotional salience but by interrupting habitual affective continuity. This challenges conventional persuasion models that emphasize emotional intensity and highlights the need for revised frameworks that account for rhythm disruption, cognitive reappraisal, and trait-level variability in user responses.</p
Steerable Subarrays for Practical mmWave Massive MIMO:Algorithm Design and System-Level Analysis
No full textThis paper investigates the application of recently proposed practical subarray (SA)-based hybrid beamforming (HBF) architectures—implemented entirely with passive beamforming networks and switches—for millimeter wave (mmWave) multi-user (MU)-MIMO base stations. Building on this practical hardware platform, we propose a joint SA configuration and signal processing framework that exploits the natural non-uniformity of user locations in 3-D space via elevation domain subsectorization. Specifically, we adapt established channel estimation and HBF techniques to the constraints of switch-based SAs, and introduce a novel 2-stage channel estimator that leverages the unique properties of mmWave channels. System-level simulations in realistic line-of-sight (LoS) and non-line-of-sight (NLoS) propagation scenarios demonstrate that the proposed solution delivers strong performance with low complexity, providing a viable path toward practical, scalable mmWave MU-MIMO deployments. In LoS scenarios, using directions-of-arrival-based channel estimation, the proposed framework achieves up to 92.6% of the average spectral efficiency (SE) of a full-digital array antenna with the same number of elements but 4 times more radio frequency chains. In NLoS environments, using the novel 2-stage estimator, this increases up to 99.7%.</p
Co-designing climate-sensitive green and blue spaces with disadvantaged urban populations
No full textUrban blue and green spaces are known for mitigating pressing climate events such as heatwaves and floods, while offering co-benefits for human health and well-being. However, these benefits are not equitably distributed, with disadvantaged groups and deprived neighbourhoods often facing limited access to green and blue spaces. Additionally, these individuals are often excluded from planning processes. This project aims to counteract these barriers by addressing the needs and preferences of disadvantaged groups and including them into urban planning processes supported by geoinformation systems (GIS) and advanced technologies such as Artificial Intelligence (AI). Focusing on Enschede, a medium-size city in the Netherlands, this interdisciplinary project uses a participatory co-design approach to bring together diverse perspectives from disadvantaged groups and decision-makers to foster collaborative and inclusive urban planning. Based on a systematic scoping literature review we synthesized knowledge on the role of blue and green spaces in enhancing well-being for disadvantaged populations, particularly in the context of extreme weather events. Building on the resulting urban green and blue space for inclusive climate and health framework, we assessed needs, perceptions, and barriers faced by disadvantaged residents using mixed methods in Enschede. While conducting two participatory workshops in collaboration with UrbanistAI and the UT DesignLab - one imagining and designing spaces suitable for disadvantaged community members with students acting as personas, and one together with disadvantaged community members and decision-makers from the area - urban planning solutions supported by GIS and AI tools were collaboratively developed. The knowledge generated in this process is being disseminated through science communication pieces, and informs collaborative educational initiatives, and contributes to the development of climate-sensitive blue and green spaces co-designed to enhance inclusivity and well-being for disadvantaged urban populations. This project was funded by the collaboration of VU Amsterdam-University of Twente awarded to the impact program Creating Responsible Societies, and also supported by a UT DesignLab Research Fellows grant
Algorithmic Management in Limbo:Task-Driven Interweaving of Hierarchy and Market Management
No full textThe growing use of algorithmic management (AM) in human resource (HR) activities has attracted growing attention from HR scholars, as organizations increasingly rely on digital labor platforms to leverage external workers. This study examines how these platforms apply AM in human resource management (HRM) and how these algorithmic systems embed both market and hierarchy management principles for shaping worker control and autonomy. Specifically, we seek to examine how AM manifests in two distinct ways across these platforms: one involving hierarchy and control, and another involving matching and autonomy. Using an inductive qualitative design, we analyzed 33 semi-structured interviews with platform workers and documentary data from 23 digital labor platforms. Whereas prior research often frames AM in binary terms—that is, market/autonomy versus hierarchy/control—we explore how task characteristics influence the joint application of both market and hierarchy principles in AM for HRM activities of digital labor platforms. Our findings show how platforms dynamically calibrate market and hierarchy approaches to AM in response to task demands, balancing flexibility, oversight, discretion, and incentives. For HR scholars, this study highlights the flexible and conditional nature of AM systems that blend autonomy and control in nuanced ways. By moving beyond the dominant autonomy-versus-control dichotomy, we show how AM is configured to align with diverse forms of work across platforms, enhancing efficiency while sustaining worker engagement amid evolving task demands.</p
Analysis and Mitigation of Conducted Common-Mode Emissions in Solid-State Transformer
No full textSolid-state transformers are potential solutions for power conversion applications with multiple ports, enabling the linking of renewable energy sources and asynchronous systems. However, the high dV/dt and parasitics in the transformer and switching devices can cause ringing (oscillation) in the collectors of the switching devices and transformers. This paper analyses the main causes of conducted common-mode emissions of solid-state transformers, including experimental measurement techniques for leakage inductance and parasitic capacitances of a transformer. In addition, the impacts of snubber and decoupling capacitors on the conducted emission and switching losses, considering single-phase shift and triple-phase shift modulations, are presented in time and frequency domains. On top of that, the effect of DC-link capacitor type on conducted emissions is investigated. Based on the experimental results, the parasitic capacitances of the switching devices and the transformer are the main propagation paths of the conducted common-mode emission. Decoupling capacitors reduce the high-frequency oscillations, but the value should be selected carefully to avoid resonance in the low-frequency ranges. Triple phase-shift modulation reduces the AC link reactive current, but it increases both conducted CM emissions and switching losses, while single phase-shift modulation increases the reactive power and reduces the conducted CM emissions.</p