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The role of policy mixes in enabling journalism innovation: a transnational study across five countries
No full textResearch has largely overlooked the macro-level conditions under which journalism innovation occurs. This study addresses the prevailing gap through a cross-country case study approach, critically examining the form, context, and nature of innovation policies for private media. Applying the policy mix framework, we analyze data from 30 semistructured interviews and 32 documents from Canada, Denmark, France, Norway, and the Netherlands. Our findings reveal that several countries have adopted a mix of different policy instruments to foster journalism innovation. They further show that innovation-policymaking for journalism often follows several uncoordinated, small events. However, despite societal trust in this type of public funding for journalism, inconsistency, incomprehensiveness, and incoherence persist in existing policy mixes. Our study yields significance for both academia and policymaking by underscoring the relevance of integrating innovation policy theory into journalism innovation research and providing practitioners with guidance for improving existing policy mixes in the future
Experimental study on efficient field measurement using ellipsoidal harmonics
No full textThis work demonstrates the application of ellipsoidal harmonic expansions for magnetic field representation in Magnetic Particle Imaging (MPI) using measured data. While previous studies focused on simulated fields, we validate the method with field data acquired from a selection field generator of an MPI head imaging system using an ellipsoidal t-design. The approach is validated by comparing the harmonic expansion results to dense principal axis measurements, confirming accurate field characterization. This study highlights the potential of ellipsoidal harmonics to improve the speed and accuracy of magnetic field measurements and representation in MPI
X-ray absorption spectroscopy reveals charge transfer in π-stacked aromatic amino acids
No full textX-ray absorption spectroscopy (XAS) and quantum mechanical calculations bear great potential to unravel π stacking side-chain interaction properties and structure in, e.g., proteins. However, core-excited state calculations for proteins and their associated interpretation for π-π interactions are challenging due to the complexity of the non-covalent interactions involved. A theoretical analysis is developed to decompose the core-to-valence transitions into their atomic contributions in order to characterize the π stacking of aromatic amino acids as a function of their non-covalent distance change. Three models were studied as a non-covalent mixed dimers of the phenylalanine, tyrosine and tryptophan amino acids. We found that there are carbon 1s → π* charge transfer transitions associated with the non-covalently paired aromatic amino acids through their side chains. The atomic-centered contributions to the electronic transition density quantify the excited state charge transfer of the pairing amino acid models, highlighting the π stacking interactions between their aromatic side chains
Vibratory and conventional impaction of acetabular components into porcine acetabula
No full textAims Sufficient primary implant stability with minimal bone damage is one of the challenges for uncemented implant fixation to prevent periprosthetic fractures and implant loosening. A pilot study on a non-viscoelastic material (polyurethane foam) showed a reduced impaction force when using vibratory implant insertion. This study assessed the effectiveness of vibratory implant insertion compared to an established implant insertion method in physiological viscoelastic bone from porcine hips. Methods Acetabular components were impacted line-to-line and into 1 mm nominal undersized cavities in porcine acetabula (n = 24 in total, n = 6 acetabula per group of study) using vibration (60 Hz) and 1 Hz (established) impaction methods. The impaction force, remaining polar gap, and lever-out moment were measured and compared between the impaction methods and different press-fits. Results The vibratory impaction method produced almost 40% lower impaction forces at both press-fit levels. However, complete seating at the nominal press-fit of 1 mm was not achieved, and primary stability was lower for the vibratory impaction for either press-fit. Conclusion Bone fracture risk due to high impaction forces could be reduced by vibrational implant insertion at the cost of a reduction in primary stability. The outcome of the vibratory impaction method in porcine bone was similar to a previous study using polyurethane foams, suggesting that the viscoelasticity of bone may not play a crucial role during press-fit implant impaction
Investigating engineering design tasks – iterative testing in large-scale engineering courses
No full textIn this research a study environment is presented that enables iterative design in large engineering lectures and show possibilities for investigations at two example lectures from German universities. The initial results show that it is possible for large lecture-hall-based courses to engage in in-depth tasks of engineering design. Design researchers can use the generated data to measure infuences, e.g. the applied methods on specifc design tasks. Two key insights include the potential for large courses to serve as large-scale research environments for design research and the observed effects of infuences on students’ decision-making processes. This approach offers a promising method to further explore the complexities of decision infuences and design optimization in educational settings
Towards reliable and high-frequency ultra-wideband ranging in agile swarms of micro aerial drones
No full textHighly agile drone swarms operating without GNSS require both high-frequency and reliable distance measurements to coordinate complex maneuvers and prevent collisions. Ultra- Wideband radios uniquely act as sensors by leveraging communication to provide centimeter-accurate localization information while simultaneously serving as a wireless medium for data exchange. However, today’s approaches to UWB swarm ranging do not provide sufficient update rates and the scalability required for complex maneuvers in large swarms. This paper presents a medium access control protocol designed for high-frequency and reliable distance measurements in highly mobile environments. Designed for mobile ad-hoc networks, it does not require static infrastructure and builds on the scalability of Many-to-Many ranging and precise time synchronization based on Glossy. Our evaluation on two testbeds shows that our proposed MAC achieves high update rates with up to 30 Hz per neighbor in a dense environment of 13 nodes
Simulation-based analysis of conflicting objectives of quay cranes and terminal trucks at container terminals
No full textQuay cranes are essential operating systems at container terminals. Their scheduling involves conflicting objectives, such as minimising vessel handling times, maximising productivity, and reducing the number of required terminal trucks. Logistic Operating Curves, known from production logistics, offer a suitable method for analysing such trade-offs and can be derived and validated through simulation. This paper proposes a simulation model of a container terminal to develop and parameterise characteristic Logistic Operating Curves. The analysis focuses on the
conflict between quay cranes productivity and number of terminal trucks. Different assignment procedures for terminal truck are considered to examine their impact on system productivity.Deutsche Forschungsgemeinschaft (DFG
NMR relaxometry for molecular structure analysis of stimuli-responsive lyogels in varied solvent polarities
No full textStimuli-responsive lyogels undergo significant macroscopic changes under external stimuli, making them ideal for applications like flow control valves or catalyst carriers in SMART reactors [1]. However, effective integration requires understanding their pore structure and diffusion behavior under various conditions, as this influences functionality. While several methods assess macroscopic swelling/shrinking, few provide microstructural insights into their swelling and shrinking state.
Nuclear Magnetic Resonance (NMR) is a suitable tool for the study of solvent dynamics inside macro, meso, and nanopores, through changes in their relaxation times and self-diffusion coefficients. Although 1H NMR relaxometry has been widely used to investigate the in-situ swelling behavior of hydrogels, microgels, and different polymer matrices [2, 3], there is still limited research on the dynamic swelling/shrinking behavior of lyogels in pure and/or mixtures of solvents of varying polarity.
In this work, we use 1H NMR relaxometry measurements (Spinsolve 60, Magritek) to investigate the microstructural changes of lyogels under different stimuli. By analyzing relaxation dynamics, we examine how molecular interactions and structural modifications respond to solvents of different polarity. These insights enhance our understanding of the physicochemical behavior of organic systems and their interactions with diverse environments.
References:
[1] K. M. Eckert, et al., Fluid Phase Equilibria 586 (2024) 114182.
[2] J. M. Giussi, et al., Soft Matter 11.45 (2015) 8879-8886.
[3] D. M. Gruber, M. S. Ferris, G. Zabow, Polymer 281 (2023) 126108.Deutsche Forschungsgemeinschaft (DFG
Automated district heating network expansion planning with resilience considerations
No full textThe use of carbon neutral heat sources such as industrial waste heat or large-scale heat pumps requires the existence of district heating networks (DHNs). The automated planning of new DHNs is a task frequently addressed in the scientific literature. Automated planning often uses the street network and geographic information system tools. Based on the potential routes for DHNs defined by the street network, the optimal DHN topology can be found using e.g. shortest path algorithms or a mixed-integer programming approach. However, to the best of the authors’ knowledge, all available approaches verify their algorithms with use cases ranging in size from villages to small cities. In addition, DHNs already exist in almost all metropolitan areas in Central Europe. The main challenge in metropolitan areas is to find the optimal DHN expansion to connect new consumers to the already existing DHN. The DHN expansion may lead to overloading of existing DHN pipes or producers, which has to be considered in the planning process. Furthermore, for larger DHNs with more than one producer, the proper operation of the DHN must be ensured even if an outtake occurs at one of the producers. Therefore, resilience has to be considered in the planning process. In this work, we present an algorithm for automated and optimal expansion planning of DHNs. The algorithm guarantees that the DHN expansion does not lead to overloads in the existing or in the added DHN pipes. In addition, a possible outtake of one producer is considered in the planning process, resulting in a resilient DHN. The algorithm is tested using a case study with more than 3000 consumers and ten generation units
Single molecule thermal gearing effect
No full textObservation of a thermally activated gearing effect between two hexa- tert -butyl-decacyclene (HBDC) molecule-gears is reported using the Au(111) surface to constrain lateral diffusion of the molecules at 77 K. An on-purpose selected small 2D HBDC nano-island is first destabilized using the tip of a scanning tunneling microscope (STM) in a soft-pulling mode of molecular manipulation. It follows a long sequence of thermally activated spontaneous molecular reconfigurations, leading up to a molecular gearing effect. Using coupled Langevin equations, a simulation of this thermal process is proposed to determine the conditions for this thermally activated gearing effect