In this letter, an additively manufactured 3$,$dB hybrid coupler is presented. While the geometrical structure is generated by a stereolithography (SLA) printer from UV curable photopolymer resin as one single part, conductive coating is provided by an electroless silverplating process. The utilized slotted waveguide approach improves the solvent flow during metal plating and therefore enables the fabrication of complex waveguide structures. Measured imbalance between the through and coupling ports stays below 1.5$,$dB over the entire E-band, while the respective phase difference ranges only between 87$° and 91$° despite the challenges of additive manufacturing in such frequency regions.

This work evaluates different metal deposition approaches for a two staged additive manufacturing process for 3D horn antennas, divided into the deposition of plastic and conductive material. The demonstrated fabrication work-flow allows for antennas of low cost, low weight and therefore demonstrates the vast benefit of additive manufacturing. The comparison of a commercially available cast aluminum horn to the fabricated prototypes reveals a deviation of up to 3 dB in terms of transmission losses in co-polarization over a distance of 1.85 m. Cross-polarization measurements are presented revealing a larger variation among the different metalization approaches. The results shown in this paper demonstrate a successful application of additive manufacturing in radio frequency engineering. Moreover, one of the presented approaches makes only use of 3D printing systems and is therefore, potentially suitable for totally automated manufacturing.

Digitisation is considered as a key transformation in urban development and retail. However, in academia, a strong focus is laid on large cities, as they are considered to be at the front line of this transformation. Second-tier cities are often neglected, although digitisation is seen as a process that offers both challenges and opportunities. This paper has two research objectives. First, it investigates the German city hierarchy using social, economic and retail data. Based on a cluster analysis of the 14 largest German cities, two clusters have been identified, revealing a stark contrast between more innovative and faster-growing areas (cluster 1) and cities with rather moderate dynamics (cluster 2). Second, Leipzig is chosen as a representative of German second-tier cities. By means of an urban living lab, the aim is to investigate the ongoing process of digitisation bringing together relevant stakeholders such as retailers, citizens, logisticians, researchers and the municipality. Different digital tools are put to the test. On that basis, living labs are discussed as a scientific approach, bridging the gap between theory and practice and adding further evidence of how digitisation takes place aside from first-tier cities.

Superparamagnetic iron oxide nanoparticles (SPIONs) have shown promise across a wide range of biomedical applications, including targeted drug delivery, magnetic hyperthermia, magnetic resonance imaging, and regenerative medicine. In the context of local tumor therapy (Magnetic Drug Targeting, MDT) SPIONs can be functionalized with chemotherapeutic agents and accumulated at tumor sites using an externally applied magnetic field. To achieve effective drug accumulation and therapeutic efficacy, precise positioning of the accumulation magnet relative to the tumor is essential. To address this need, we propose a dual-modality ultrasound imaging approach combining magnetomotive ultrasound (MMUS) and passive cavitation mapping (PCM). MMUS detects magnetically induced displacements to localize SPIONs embedded in elastic tissue, while PCM monitors cavitation emissions from circulating SPIONs under focused ultrasound exposure. In addition to detection, PCM has the potential to enable feedback-based control of cavitation exposure, allowing cavitation parameters to be kept within a safe regime. The dual imaging modality approach was validated using standard phantoms and a complex carotid bifurcation tumor flow phantom fabricated via 3D printing. Experimental results demonstrate the first coordinated spatiotemporal imaging of MMUS and PCM within the same anatomical model, resolving the key bottleneck of SPIONs monitoring in blood vessels/tissue. This demonstrates the strong potential of complementary MMUS and PCM imaging for monitoring in preclinical and clinical MDT settings.

Superparamagnetic iron oxide nanoparticles (SPIONs) have shown promise across a wide range of biomedical applications, including targeted drug delivery, magnetic hyperthermia, magnetic resonance imaging, and regenerative medicine. In the context of local tumor therapy (Magnetic Drug Targeting, MDT) SPIONs can be functionalized with chemotherapeutic agents and accumulated at tumor sites using an externally applied magnetic field. To achieve effective drug accumulation and therapeutic efficacy, precise positioning of the accumulation magnet relative to the tumor is essential. To address this need, we propose a dual-modality ultrasound imaging approach combining Magnetomotive Ultrasound (MMUS) and Passive Cavitation Mapping (PCM). MMUS detects magnetically induced tissue displacements, allowing localization of SPIONs embedded in tissue. However, MMUS is ineffective in vascular regions where no tissue displacement occurs. To overcome this, we use PCM to image circulating SPIONs, which are engineered to emit cavitation signals under focused ultrasound exposure. This complementary method enables SPIONs monitoring within tissue and flow. Validation was performed using standard phantoms and a custom-designed carotid bifurcation tumor flow phantom fabricated with 3D printing. Experimental results confirm that this hybrid strategy effectively images SPIONs in both tumor tissue and vasculature. This demonstrates the strong potential of complementary MMUS and PCM imaging for monitoring in preclinical and clinical MDT settings.