TY - CONF A1 - Riedel, Soraya A1 - Talke, A. A1 - Lisdat, F. T1 - Enzyme activity determination of human monoamine oxidase B (Mao B) by amperometric hydrogen peroxide detection N2 - Parkinson’s disease (PD) is one of the most common neurodegenerative disorders worldwide. About 0.3 % of the global population and approximately 2 % of people older than 80 years are affected by PD. Monoamine oxidase B (Mao B) is an enzyme, which is a drug target in Parkinson’s disease (PD), since it is involved in dopamine metabolism. Several Mao B inhibitors are well established as medication for PD patients. However, the medical treatment is only little personalized since the monitoring of the patients Mao B activity is complex and requires sophisticated laboratory equipment. Here a sensorial Mao B activity determination system has been developed which has potential in the personalization of the medical PD treatment. The enzyme activity is quantified by amperometric detection of enzymatically produced H2O2. Therefore, the enzyme is enriched from the solution via cellulose particles which are functionalized with antibodies against human Mao B. The successful capturing of the enzyme can be verified by SDS-PAGE. For activity determination the enzyme is brought in contact with a suitable substrate - here benzylamine. Selectivity of the amperometric hydrogen peroxide detection in the presence of co-reactants has been verified. Within the time span of 30 min, a linear dependency of enzymatically produced H2O2 with the substrate incubation time can be observed. This allows the evaluation of the Mao B activity. The results have been correlated to an optical detection method. Furthermore, the method has been tested for different amounts of enzyme used in the experiments and found to be sensitive enough for Mao B analysis in blood samples. T2 - European Biosensor Symposium 2021 CY - Online meeting DA - 09.03.2021 KW - Monoamine oxidase B KW - Amperometry KW - Prussian blue KW - Parkinsons's disease KW - Screen-printed electrodes PY - 2021 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. AN - OPUS4-52270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bulling, Jannis T1 - Numerical methods (part II) Finite element method (FEM), Spectral element method (SEM) and Scaled Boundary FEM (SBFEM) N2 - A general presentation on numerical methods. In particular, the Finite Element Method, the Spectral Element Method, and the Scaled Boundary Finite Element Method. T2 - ITN-Trainingsevent CY - Online meeting DA - 22.11.2020 KW - FEM KW - SBFEM KW - SEM PY - 2020 AN - OPUS4-52271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bulling, Jannis A1 - Gravenkamp, Hauke T1 - A Combination of the Scaled Boundary Finite Element Method with the Mortar Method N2 - The simulation of ultrasonic waves in a linearly elastic body can be computationally intensive. The reason is the relatively short wavelength compared to the body size for high frequencies. One possible approach to counteract the high computational costs is to decompose the domain into small parts and strive for parallelization. The Mortar Method is a well-established approach for domain decomposition. A rather new approach to discretize the emerging subdomains is the Scaled Boundary Finite Element Method. This semi-analytical method has many attractive properties. Some of these properties are listed subsequently. The grid consists of polygonal elements, which leaves much freedom in the meshing process. A variety of material distributions, including anisotropic materials, can be considered. High-order shape functions can be used for optimal convergence properties. The approach treats singularities at crack tips and corners analytically. Especially in the frequency domain, the Scaled Boundary Finite Element Method reduces the dimension of the approximation because only degrees of freedom which are associated with the boundary of a polygonal element are necessary. Those desirable properties make the method particularly suitable for calculating the dynamic responses in bodies with cracks, as it is essential for many non-destructive testing and structural health monitoring applications. In this contribution, we present a combination of the Scaled Boundary Finite Element Method with the Mortar Method in two dimensions. The presentation starts with a theoretical overview of both approaches. Subsequently, numerical examples demonstrate the stability of the combination for the polygonal boundary of the elements. The numerical examples increase in complexity and are compared to results computed on non-divided domains with the Finite Element Method. T2 - WCCM-ECCOMAS CONGRESS CY - Online meeting DA - 11.01.2021 KW - Ultrasound KW - Numerical Simulation KW - Scaled Boundary Finite Element Method, Mortar Method PY - 2021 AN - OPUS4-52275 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Melzer, Michael T1 - Seminar about the expression of uncertainty in measurement N2 - The evaluation of measurement uncertainty is essential for testing and calibration laboratories. This paper provides a general process description for the determination of the measurement uncertainty of quantitative data and its application to the conformity assessment with examples, and how to deal with the uncertainty of qualitative (Boolean) results, e. g. when "Alarm" or "No alarm" occours in an instrument display. T2 - GW4SHM - 1st Training Event CY - Online meeting DA - 23.11.2020 KW - Uncertainty KW - Conformity assessment KW - Boolean results PY - 2020 AN - OPUS4-52040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rühle, Bastian A1 - Krumrey, Julian Frederic A1 - Hodoroaba, Vasile-Dan T1 - Workflow towards automated segmentation of agglomerated, non‑spherical particles from electron microscopy images using artificial neural networks N2 - We present a workflow for obtaining fully trained artificial neural networks that can perform automatic particle segmentations of agglomerated, non-spherical nanoparticles from scanning electron microscopy images “from scratch”, without the need for large training data sets of manually annotated images. The whole process only requires about 15 minutes of hands-on time by a user and can typically be finished within less than 12 hours when training on a single graphics card (GPU). After training, SEM image analysis can be carried out by the artificial neural network within seconds. This is achieved by using unsupervised learning for most of the training dataset generation, making heavy use of generative adversarial networks and especially unpaired image-to-image translation via cycle-consistent adversarial networks. We compare the segmentation masks obtained with our suggested workflow qualitatively and quantitatively to state-of-the-art methods using various metrics. Finally, we used the segmentation masks for automatically extracting particle size distributions from the SEM images of TiO2 particles, which were in excellent agreement with particle size distributions obtained manually but could be obtained in a fraction of the time. KW - Electron microscopy KW - Neural networks KW - Artificial intelligence KW - Image segmentation KW - Automated image analysis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522454 DO - https://doi.org/10.1038/s41598-021-84287-6 VL - 11 IS - 1 SP - 4942 PB - Springer Nature AN - OPUS4-52245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rühle, Bastian A1 - Krumrey, Julian Frederic A1 - Hodoroaba, Vasile-Dan T1 - Dataset accompanying the publication "Workflow towards automated segmentation of agglomerated, non-spherical particles from electron microscopy images using artificial neural networks" N2 - This dataset accompanies the following publication, first published in Scientific Reports (www.nature.com/articles/s41598-021-84287-6): B. Ruehle, J. Krumrey, V.-D. Hodoroaba, Scientific Reports, Workflow towards Automated Segmentation of Agglomerated, Non-Spherical Particles from Electron Microscopy Images using Artificial Neural Networks, DOI: 10.1038/s41598-021-84287-6 It contains electron microscopy micrographs of TiO2 particles, the corresponding segmentation masks, and their classifications into different categories depending on their visibility/occlusion. Please refer to the publication and its supporting information for more details on the acquisition and contents of the dataset, as well as the GitHub repository at https://github.com/BAMresearch/automatic-sem-image-segmentation KW - Electron microscopy KW - Neural networks KW - Image segmentation KW - Automated image analysis PY - 2021 DO - https://doi.org/10.5281/zenodo.4563942 PB - Zenodo CY - Geneva AN - OPUS4-52246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Essig, W. A1 - Bernhardt, Y. A1 - Döring, D. A1 - Solodov, I. A1 - Gautzsch, T. A1 - Gaal, Mate A1 - Hufschläger, Daniel A1 - Sommerhuber, R. A1 - Marhenke, T. A1 - Hasener, J. A1 - Szewieczek, A. A1 - Hillger, W. T1 - Air-coupled ultrasound - emerging NDT method N2 - This paper deals with the state of the art of air-coupled ultrasonic testing. KW - Air-coupled KW - Ultrasonic testing KW - Transducers PY - 2021 SN - 1616-069X VL - 173 SP - 32 EP - 43 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-52231 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Plarre, Rüdiger A1 - Zocca, Andrea A1 - Spitzer, Andrea A1 - Benemann, Sigrid A1 - Gorbushina, Anna A1 - Li, Y. A1 - Waske, Anja A1 - Funk, Alexander A1 - Wilgig, Janka A1 - Günster, Jens T1 - Searching for biological feedstock material: 3D printing of wood particles from house borer and drywood termite frass N2 - Frass (fine powdery refuse or fragile perforated wood produced by the activity of boring insects) of larvae of the European house borer (EHB) and of drywood termites was tested as a natural and novel feedstock for 3D-printing of wood-based materials. Small particles produced by the drywood termite Incisitermes marginipennis and the EHB Hylotrupes bajulus during feeding in construction timber, were used. Frass is a powdery material of particularly consistent quality that is essentially biologically processed wood mixed with debris of wood and faeces. The filigree-like particles flow easily permitting the build-up of woodbased structures in a layer wise fashion using the Binder Jetting printing process. The Quality of powders produced by different insect species was compared along with the processing steps and properties of the printed parts. Drywood termite frass with a Hausner Ratio HR = 1.1 with ρBulk = 0.67 g/cm3 and ρTap = 0.74 g/cm3 was perfectly suited to deposition of uniformly packed layers in 3D printing. We suggest that a variety of naturally available feedstocks could be used in environmentally responsible approaches to scientific material sciences/additive manufacturing. KW - 3D printing KW - X-ray tomographic KW - SEM micrography KW - Drywood termite PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521517 DO - https://doi.org/10.1371/journal.pone.0246511 VL - 16 IS - 2 SP - e0246511 AN - OPUS4-52151 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos A1 - Stawski, Tomasz A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska T1 - Crystallisation of transition metal phosphate as precursors for mesoporous materials N2 - The influence of several precipitation parameters on the crystal morphology and size of transition metal struvite is poorly investigated. We reveal the effect of different reaction conditions on the crystal shape and crystallite size of M-struvites (NH4MPO4∙6H2O, M = Mg2+, Ni2+, Co2+). Furthermore, we characterize the coordination environment of the crystalline end products and their related phases [Co-dittmarite (COD) NH4CoPO4∙H2O and Co(II)phosphate octahydrate (CPO) Co3(PO4)2∙8H2O]. Mg- and Ni-struvite are stable in multiple concentrations of the educts and metal/phosphorus (M/P) ratios in contrast to Co-struvite which forms below M/P ratios of 0.4. A high M/P ratio with high concentrations of the educts decrease the crystallite size and idiomorphism of the crystals while low M/P ratios with low concentrations of the educts increase the crystallite size and the euhedral formation of the crystal planes. In the (Ni, Co)-solid solutions Ni and Co are homogenously distributed in the crystals with similar Ni# as in the aqueous solutions indicating no elemental fractionation in crystallization. Ni and Co-struvite exhibit a more centrosymmetric coordination environment compared to their related phases of COD and CPO determined by EXAFS. The CoO6 octahedron expands slightly the ideal size of the struvite structure and decomposes to Co-dittmarite. It is suggested that the crystallization of Ni- and Co-struvites follow a non-classical crystallization theory which consists of multiple nanophases on the way to the final crystal. T2 - SALSA Make and Measure... and Machines CY - Online meeting DA - 16.09.2021 KW - Crystal Engineering KW - Nucleation KW - Mesoporosity PY - 2021 AN - OPUS4-53444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos A1 - Stawski, Tomasz T1 - Crystallisation and nucleation study of transition metal struvite and related compounds N2 - The recycling of critical elements has crucial importance to maintain sustainable use of raw materials. Phosphorus(P) is a sought-after limited natural resource due to its wide use in modern agriculture mainly as P-fertilizers. But it causes major problems for the environment such as eutrophication of ecosystems. In the future it could be depleted due to the high demand and declining natural phosphorite ore deposits. Therefore, the phosphorus recovery from agricultural waste waters will be an important factor in preservation of the global consumption. The precipitation of M-struvite (NH4MPO4·6H2O, M2+= Mg2+, Ni2+, Co2+, Zn2+, Cu2+ etc.) from agricultural and mine waste waters is a promising P-recovery route. Besides avoidance of eutrophication due to extraction of excess phosphates and the restoration of the phosphorus resources the recovered M-struvites may be potentially be up-cycled for industrial applications e.g. Co and Ni-phosphate show excellent electrochemical properties for batteries or supercapacitors. The precipitation processes of M-struvites are strongly dependent on the degree of supersaturation, pH and on the exchange ions M2+.The impact of transition metals on the crystallization of M-struvite has been investigated only to a limited extent. An optimization of the reaction conditions could lead to more efficient M-struvite precipitation and significantly improved P-recovery method. In addition, these materials form transitional amorphous colloidal nanophases on the way to the crystalline product indicating a non-classical crystallization pathway. By interfering the crystallization process a potential highly reactive amorphous precursor material can be preserved for electrocatalysis. Here, we present hints on the crystallization mechanism and the kinetics of precipitation through analysis of the transitional phases. Furthermore, we reveal the effect of different reaction conditions on the crystal shape and crystallite size of M-struvites (NH4MPO4∙6H2O, M = Mg2+, Ni2+, Co2+). In addition, we could evaluate the stability of crystalline M-struvites and their related phases through characterization of the coordination environment [Co-dittmarite (COD) NH4CoPO4∙H2O and Cobalt(II)phosphate octahydrate (CPO) Co3(PO4)2∙8H2O].Due to the low solubility product and their controlled precipitation through adjusting the reaction conditions (c(educts), pH, multi metal solutions) M-struvite is a promising recovery material as it could extract NH4+, PO43- and heavy metals at the same time out of agricultural and mine waste waters. T2 - IUCr 25th International Union of Crystallography Congress CY - Online meeting DA - 14.08.2021 KW - Crystal Engineering KW - Nucleation KW - Amorphous Phases KW - Crystal mechanism PY - 2021 AN - OPUS4-53445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -