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Collaboration between civil society and state authorities in preventing radicalization has often been met with scepticism in academic debates, particularly due to concerns about power asymmetries, structural inequalities, and the risk of co-optation. While existing literature offers critical insights into national institutional frameworks and their implications for civil society, it frequently overlooks the local dynamics that shape prevention practices on the ground. The paper addresses this gap by examining cooperation between municipal officials and civil society organizations (CSOs) in local preventive efforts, focusing on the relatively understudied case of Germany. Specifically, this pilot study centres on the perspectives of municipal actors rather than directly capturing CSO voices. Drawing on 14 semi-structured interviews with municipal officers in Germany, it explores how collaboration is influenced not only by their formal mandates, but also by individual professional trajectories and locally embedded networks. The findings show that local cooperation in the prevention field is more contingent and negotiated than commonly acknowledged. Enabling factors and persistent challenges - such as lack of trust, divergent expectations, and the limited capacities of smaller CSOs - affect the quality and sustainability of these partnerships. By foregrounding lived experience and first-person perspectives of municipal officials, the paper advances a more grounded and relational understanding of state-civil society collaboration, one that accounts for the hybrid arrangements and interpersonal dynamics through which preventive efforts unfold at the local level.
Silicon nanowire field emitters were fabricated on top of microtubes on a silicon chip (dimensions including contact pads: 8 × 8 mm). There are 2437 microtubes (diameter: 8 μm, height: 30 μm, spacing: 40 μm) in the array over an area of 3.38 mm2. A process was developed to create an integrated metal gate for the extraction electrode. This involved coating the emitters with a uniform benzocyclobutene layer and fabricating a titanium/nickel extraction gate using lift-off. A plasma etching process was used to selectively remove the benzocyclobutene anisotropically around the microtubes, ensuring the preservation of the emitters and the extraction gate. The design reduces the capacitance between the cathode and gate and maximizes the length of the leakage paths between the cathode and gate. This reduces the overall risk of discharges between the two electrodes as well as the energy stored in the system for a given extraction voltage. The electron sources demonstrated transmission rates exceeding 96%, with currents reaching 0.4 mA at extraction voltages of 250 V for several hours under voltage-controlled operation. Investigations after the measurements showed that isolated discharges destroyed individual emitters during operation, but the electron sources remained functional. Consequently, these cathodes demonstrated resilience to failure caused by discharge-related damage due to the low capacity of the system. At higher voltages (300 V) and currents (2 mA); however, these samples exhibited catastrophic arcing, as at these voltages, the energy stored in the capacitance was large enough to result in the destruction of larger areas of the arrays and the formation of conductive paths between the cathode and the gate.
A major challenge in cochlear implant (CI) therapy is postoperative inflammation, which can compromise long-term electrode function. Conventional interleukin-6 (IL-6) detection is challenging due to factors such as its inherent instability. In this study, we present a cost-effective detection strategy using epitope-specific molecularly imprinted polymer nanoparticles (nanoMIPs). These nanoMIPs enable sensitive detection of both IL-6 and its epitope, representing a scalable and economical alternative for inflammation monitoring. NanoMIPs were embedded in a biodegradable chitosan matrix and sprayed onto electrodes. To detect the biomarker, electrochemical impedance spectroscopy was used, a functionality which is already embedded in CI circuits. The sensors enabled reliable detection of IL-6 down to 29 pg/mL, which represents the lowest concentration investigated in this study, with improved sensitivity to the small epitope, as the larger protein causes higher impedance changes due to steric hindrance. Additionally, the sensors enabled concentration-dependent IL-6 detection in human perilymph samples down to 2 pg/mL, with higher signal responses for IL-6 relative to other perilymph components. Comparison with an immunoassay supported analytical accuracy and diagnostic relevance. The sensors were subsequently tested weekly for functionality over four weeks under physiological conditions, with nanoMIP:chitosan ratios of 1:6 and 1:8 being optimal for long-term monitoring. Moreover, the nanoMIPs have a diameter of 56 nm (a parameter that can influence physiological excretion) and cytotoxicity tests demonstrated their biocompatibility. This work presents an epitope-based nanoMIP sensor platform that overcomes economic and biochemical limitations of protein-based biosensors, enabling advanced, real-time self-monitoring CI systems for in-vivo inflammation tracking to reduce implant failure.
This project is funded by the German Research Foundation (DFG) under Germany's Excellence Strategysingle bondEXC2177/1-Project ID 390895286 (“Cluster of Excellence Hearing4All”). Funding was also provided by the Research Foundation Flanders (FWO) under the project name “Catheter-based sensors for the intestinal detection of molecular biomarkers in the context of functional bowel disorders” and the project ID G0A6821N. Additional funding was provided by the USDA National Institute of Food and Agriculture, AFRI project 2022–67,021-36,408 and project EP/W031590/2 from the Engineering and Physical Sciences Research Council.
Metal-organic frameworks (MOFs), such as Zeolitic Imidazolate Framework-8 (ZIF-8), are increasingly explored for sensing applications. In this field, the formation of uniform thin films is often essential. This study details the deposition and stepwise characterization of covalently bonded ZIF-8 thin films for methane sensing on two types of silica-based substrates: silicon wafers with native oxide and optical fibers. We emphasize practical and accessible methods to verify each step of the deposition process. Surface preparation was tailored to each substrate. Silicon wafer substrates were cleaned using Caro’s acid, while optical fibers were activated via oxygen plasma to account for handling constraints. Both substrate types were subsequently functionalized with a monolayer of isopropyltrimethoxysilane (IPTES) to promote covalent bonding of ZIF-8. Particles of ZIF-8 were deposited using a seeded growth approach. Solvothermal synthesis of ZIF-8 was performed, while simultaneously immersing the substrates in the synthesis solution, promoting the formation of a continuous thin film. The deposition process was characterized at each stage. Free ZIF-8 powder obtained from the synthesis was centrifuged, washed with ethanol and analyzed by attenuated total reflection infrared (ATR-IR) spectroscopy. Silicon wafers enabled contact angle measurements to assess IPTES functionalization, as well as spectroscopic ellipsometry for analysis of the formed ZIF-8 thin film. Scanning electron microscopy (SEM) was used to examine film morphology on both substrate types. To evaluate methane sensitivity, optical fibers coated with ZIF-8 were exposed to vacuum and methane atmospheres, while changes in transmitted optical power were monitored to probe refractive index variations.
We introduce a compact model for the prediction of performance figures of CMUTs prospectively used in airborne applications such as flow meters. The model comprises both a mechanical and an electrical approach resulting in a set of four parameters: resonance frequency, Q-factor, static capacitance and pull-in voltage. A small set of exemplary CMUTs has been intensively characterized by means of LDV and LCR measurements, eventually confirming the precision of the proposed prediction model.
The choice of wireless technology for a pest monitoring setup is crucial for energy efficiency and reliability. We analysed 48 different modules with regards to bitwise energy consumption theoretically and evaluated the best modules in real-life scenarios. It was found that the choice of module can be inferred from a thorough market analysis and Narrowband Internet of things (NB-IoT) and Long Range (LoRa) are the most promising candidates for deployment in industrial environments. Regarding the tested site NB-IoT showed a coverage of over 97 % with good signal quality. For LoRa a calculation of the coverage percentage is not reasonable, as it strongly depends on the amount and location of the gate-ways. It was determined that one gateway can cover more than 10,000 m(exp 2). The results indicate that NB-IoT is suitable for wireless transmission in industrial environments and that LoRa with an individual gateway setup is ideal as a backup solution.
This work provides insight into the potential of camera-based surface plasmon resonance sensors when utilising the spatial sensor by modulating the sensor response through lateral modification of surface parameters or input illumination. These modifications have to be coupled with adequate signal processing. Modelling the sensor response using Fresnel formulae allows for accurate representation of the sensor surface state, increasing confidence in measured values. Alternatively, data-based modelling approaches can be utilised which eliminate the need for approximation of a physical model to observed data but are limited by the data they are trained on.
It has been explored how, especially, deep learning models that are specialised in image processing (CNNs) can be utilised for qualitative or quantitative assessment of analytes with the help of a receptor array on an SPR surface. Notably, this approach demonstrates strong generalization capabilities, performing effectively on unseen sensors used for the same task. Preliminary experiments indicate that performance enhancements are feasible when data from different points in time during binding or debinding are used during processing.
In conclusion, deep learning-assisted spatial SPR sensors hold immense potential for diverse applications, including online quality control, anomaly detection, and biofouling quantification. However, realizing this potential hinges on carefully designed experiments that yield high-quality data. Furthermore, incorporating orthogonal data sources is crucial for more precise determination of the surface state during calibration. Suitable surface-sensitive techniques include Raman spectroscopy, ellipsometry, and impedance spectroscopy. Coupling these methods can improve knowledge on the observed state during training. This information together with the presented methods can simplify sensor development and improve performance.
Diese Arbeit gibt einen Einblick in das Potenzial kamerabasierter Oberflächenplasmonenresonanzsensoren, wenn der räumliche Sensor durch die Modulation von Sensorreaktionen durch laterale Modifikation der Oberflächenparameter oder der Eingangsbeleuchtung genutzt wird. Diese Modifikationen erzeugen eine komplexe Sensorantwort und müssen daher mit einer geeigneten Signalverarbeitung gekoppelt werden. Die Modellierung der Sensorantwort mit Hilfe von Fresnel-Formeln ermöglicht eine genaue Bestimmung des Sensoroberflächenzustands und erhöht so die Konfidenz in gemessene Werte. Alternativ können datenbasierte Modellierungsansätze angewandt werden, die eine Annäherung eines physikalischen Modells an aufgenommene Daten ersetzen können, aber durch die Daten, auf denen sie trainiert werden, begrenzt sind.
Es wurde untersucht, wie insbesondere tiefe neuronale Netze, die auf die Bildverarbeitung spezialisiert sind (CNNs), für die qualitative oder quantitative Bewertung von Analyten mit Hilfe eines Rezeptor-Arrays auf einer SPR-Oberfläche eingesetzt werden können. Insbesondere zeigt dieser Ansatz starke Generalisierungsfähigkeiten, die auch bei unbekannten (unkalibrierten) Sensoren, die für dieselbe Aufgabe verwendet werden, wirksam sind. Vorläufige Experimente deuten darauf hin, dass Genauigkeitssteigerungen möglich sind, wenn bei der Verarbeitung Daten von verschiedenen Zeitpunkten während der Bindung verwendet werden.
Zusammenfassend lässt sich sagen, dass räumliche SPR-Sensoren mit Hilfe von tiefen neuronalen Netzen immenses Potenzial für verschiedene Anwendungen haben, darunter Online-Qualitätskontrolle, Erkennung von Anomalien und Quantifizierung von Biofouling. Die Realisierung dieses Potenzials hängt jedoch von sorgfältig geplanten Experimenten ab, die qualitativ hochwertige Daten liefern. Darüber hinaus ist die Einbeziehung orthogonaler Datenquellen entscheidend für eine genauere Bestimmung des Oberflächenzustands während der Kalibrierung. Zu geeigneten oberflächensensitiven Techniken gehören Raman-Spektroskopie, Ellipsometrie und Impedanzspektroskopie. Die Kopplung dieser Methoden kann das Wissen über den beobachteten Zustand während des Trainings verbessern. Diese Informationen können zusammen mit den vorgestellten Methoden die Sensorentwicklung vereinfachen und die Leistung des Sensors in der Anwedung verbessern.