Untersuchung des Einflusses verschiedener Testparameter auf die Wirksamkeit ausgewählter antimikrobieller Peptide

Die sich permanent verschlechternde Resistenzlage im Bereich der Antibiotika führt zu einem wachsenden Bedarf an Alternativen zur Bekämpfung pathogener Bakterien (Schroeder et al., 2017). Eine Möglichkeit kann der Einsatz von antimikrobiellen Peptiden sein, die ihr hohes Potential in der Natur bereits unter Beweis gestellt haben. Dementsprechend wird auch schon seit einigen Jahren an Möglichkeiten der pharmazeutischen Anwendung geforscht (Kosikowska & Lesner, 2016). Diese bergen neben neuen Chancen natürlich auch neue Gefahren, zu denen die Entwicklung von Resistenzen gegen antimikrobielle Peptide der körpereigenen Abwehr zählt (Dobson et al., 2014). Zur Resistenztestung von antimikrobiellen Peptiden gibt es noch keine standardisierten MHK-Tests. Vor diesem Hintergrund befasste sich diese Arbeit mit verschiedenen Testparametern, die die Etablierung eines solchen MHK-Tests beeinflussen können. Es wurde nachgewiesen, dass die mit steigender Konzentration von Bakterienmedium in den Ansätzen sinkende antimikrobielle Aktivität von hBD-2 und RNase 7 mit dem Bakterieninokulum zusammenhängt. Darüber hinaus konnte nachgewiesen werden, dass im Fertigungsprozess oder in der Lagerung oxidierte RNase 7 eine, im Gegensatz zu nicht oxidierter RNase 7, geringere antibakterielle Aktivität besitzt. Letztlich konnte noch eine mögliche Umsetzung eines adaptierten MHK-Tests von hBD-2 gegen Staphylococcus aureus entwickelt und eine Empfehlung zur Nutzung von Polystyrol-Mikrotiterplatten ausgesprochen werden

Calibration and evaluation of optical systems for full-field strain measurement

The design and testing of a reference material for the calibration of optical systems for strain measurement is described, together with the design and testing of a standardized test material that allows the evaluation and assessment of fitness for purpose of the most sophisticated optical system for strain measurement. A classification system for the steps in the measurement process is also proposed and allows the development of a unified approach to diagnostic testing of components or sub-systems in an optical system for strain measurement based on any optical technique. The results described arise from a European study known as SPOTS whose objectives were to begin to fill the gap caused by a lack of standards

Comparison of ICP-AlOx and ALD-Al2O3 layers for the rear surface passivation of c-Si solar cells

The deposition rate of the standard (i.e. sequential) atomic layer deposition (ALD) process is very low compared to the plasma-enhanced chemical vapour deposition (PECVD) process. Therefore, as a short- and medium-term perspective, PECVD aluminium oxide (AlOx) films might be better suited for the implementation into industrial-type solar cells than ALD-Al 2O3 films. In this paper, we report results achieved with a newly developed PECVD deposition process for AlOx using an inductively coupled plasma (ICP). We compare the results to high-quality ALDAl2O3 films. We examine a stack consisting of a thin AlOx passivation layer and a PECVD silicon nitride (SiNy) capping layer. Surface recombination velocities below 9 cm/s were measured on low-resistivity (1.4 Ωcm) p-type crystalline silicon wafers passivated either by ICP-PECVD-AlOx films or by ALD-Al2O3 films after annealing at 425°C. Both passivation schemes provide an excellent thermal stability during firing at 910°C with SRVs below 12 cm/s for both, Al2O3/SiNy stacks and single Al 2O3 layers. A fixed negative charge of -4×10 12 cm-2 is measured for ICP-AlOx and ALD-Al2O3, whereas the interface state density is higher for the ICP-AlOx layer with values of 11.0×1011 eV-1cm-2 compared to 1.3×1011 eV -1cm-2 for ALD-Al2O3. Implemented into large-area screen-printed PERC solar cells, an independently confirmed efficiency of 20.1% for ICP-AlOx and an efficiency of 19.6% for ALD-Al2O3 are achieved.BMU/0325296Solland Solar Cells BVSolarWorld Innovations GmbHSCHOTT Solar AGRENA GmbHSINGULUS TECHNOLOGIES A

Steps Towards Industrial Validation Experiments

Imaging systems for measuring surface displacement and strain fields such as stereoscopic Digital Image Correlation (DIC) are increasingly used in industry to validate model simulations. Recently, CEN has published a guideline for validation that is based on image decomposition to compare predicted and measured data fields. The CEN guideline was evaluated in an inter-laboratory study that demonstrated its usefulness in laboratory environments. This paper addresses the incorporation of the CEN methodology into an industrial environment and reports progress of the H2020 Clean Sky 2 project MOTIVATE. First, while DIC is a well-established technique, the estimation of its measurement uncertainty in an industrial environment is still being discussed, as the current approach to rely on the calibration uncertainty is insufficient. Second, in view of the push towards virtual testing it is important to harvest existing data in the course of the V&V activities before requesting a dedicated validation experiment, specifically at higher levels of the test pyramid. Finally, it is of uttermost importance to ensure compatibility and comparability of the simulation and measurement data so as to optimize the test matrix for maximum reliability and credibility of the simulations and a quantification of the model quality