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Nanostructuring of the titanium alloy Ti-13Nb-13Zr (NanoTNZ) for osteosynthesis implants by continuous multidirectional swaging
No full textBeitrag zum Grenzverformungsverhalten und zur Gebrauchstauglichkeit horizontaler mineralischer Deponiebarrieren
No full textMit dem Mitteilungsheft Nr. 40 publizieren das Institut und die Versuchsanstalt für Geotechnik der Technischen Universität Darmstadt die wissenschaftliche Arbeit von Herrn
Dr.-Ing. Lorenz Edelmann. Darin berichtet Dr. Edelmann über die von ihm im Maßstab
1:1 durchgeführten großmaßstäblichen Modellversuche im 4,20 m großen Darmstädter
Verformungssimulator für horizontale Deponiebarrieren
Rapid Scalable One‐step Production of Catalysts for Low‐Iridium Content Proton Exchange Membrane Water Electrolyzers
No full textProton exchange membrane water electrolysis (PEMWE) is a promising technology for green hydrogen production, although its widespread development with state‐of‐the‐art loadings is threatened by the scarcity of iridium (Ir). Homogeneous dispersion of Ir in an immiscible electro‐ceramic matrix can enhance catalytic mass activity and structural stability. The study presents IrySn₀.₉(₁₋y)Sb₀.₁(₁₋y)Oₓ solid solutions produced by highly scalable flame spray pyrolysis (FSP) process as efficient anode electrocatalysts for PEMWE, containing only 0.2 mg cm⁻² of Ir in the catalyst layer (CL). Intense mixing of metal vapor and large thermal gradients in the precursor‐derived high‐temperature flame aids stabilizing sub‐nanoscale entropic mixing within self‐preserved 4–6 nm particles. Detailed investigations confirm that the one‐step prepared solid solution electrocatalysts exhibit up to fourfold higher activity toward the oxygen evolution reaction (OER) compared to Ir black. The anode of a PEMWE utilizing this catalyst exhibits high performance and stability over 2000 h but with tenfold lower Ir loading than the state‐of‐art
Automation-aided construction and characterization of Bacillus subtilis PrsA strains for the secretion of amylases
No full textProteins face an obstacle race on their way to successful folding. Chaperones facilitate the proper folding of proteins by ensuring they remain on the correct path toward their final tertiary structure. In bacilli, the PrsA chaperone is essential for the correct folding and stabilization of proteins within the cell wall. Overexpression of the PrsA chaperone has been shown to improve the successful folding and secretion of many biotechnologically relevant secreted enzymes. This resulted in a double benefit: firstly, it promotes the efficient release of properly folded enzymes from the cell wall, and second, it reduces the folding stress for the cell, thereby enhancing the overall fitness of the production organism. This paper presents a workflow in which different wild-type PrsA molecules in Bacillus subtilis are co-expressed with different amylases having different signal peptides and promoters. To achieve this, six genome-reduced strains and nine PrsA proteins were systematically selected based on their cultivation performance and the production of two reference amylases. Following strain selection and deletion of major extracellular proteases, several hundred individual strains were created and screened using a stepwise and modular automation approach combined with amplicon sequencing. In addition to providing the key learnings from the workflow, it was revealed that no single PrsA molecule consistently improved amylase production, but genetic constructs combining different elements showed up to a 10-fold variation in yield. Among the screened constructs, the signal peptides YdjM and YvcE demonstrated the best performance
Rapid scalable one‐step production of catalysts for low‐iridium content proton exchange membrane water electrolyzers
No full textProton exchange membrane water electrolysis (PEMWE) is a promising technology for green hydrogen production, although its widespread development with state‐of‐the‐art loadings is threatened by the scarcity of iridium (Ir). Homogeneous dispersion of Ir in an immiscible electro‐ceramic matrix can enhance catalytic mass activity and structural stability. The study presents IrySn₀.₉(₁₋y)Sb₀.₁(₁₋y)Oₓ solid solutions produced by highly scalable flame spray pyrolysis (FSP) process as efficient anode electrocatalysts for PEMWE, containing only 0.2 mg cm⁻² of Ir in the catalyst layer (CL). Intense mixing of metal vapor and large thermal gradients in the precursor‐derived high‐temperature flame aids stabilizing sub‐nanoscale entropic mixing within self‐preserved 4–6 nm particles. Detailed investigations confirm that the one‐step prepared solid solution electrocatalysts exhibit up to fourfold higher activity toward the oxygen evolution reaction (OER) compared to Ir black. The anode of a PEMWE utilizing this catalyst exhibits high performance and stability over 2000 h but with tenfold lower Ir loading than the state‐of‐art
Model compression techniques in biometrics applications: A survey
No full textThe development of deep learning algorithms has extensively empowered humanity’s task automatization capacity. However, the huge improvement in the performance of these models is highly correlated with their increasing level of complexity, limiting their usefulness in human-oriented applications, which are usually deployed in resource-constrained devices. This led to the development of compression techniques that drastically reduce the computational and memory costs of deep learning models without significant performance degradation. These compressed models are especially essential when implementing multi-model fusion solutions where multiple models are required to operate simultaneously. This paper aims to systematize the current literature on this topic by presenting a comprehensive survey of model compression techniques in biometrics applications, namely quantization, knowledge distillation and pruning. We conduct a critical analysis of the comparative value of these techniques, focusing on their advantages and disadvantages and presenting suggestions for future work directions that can potentially improve the current methods. Additionally, we discuss and analyze the link between model bias and model compression, highlighting the need to direct compression research toward model fairness in future works
Entwicklung und Zuverlässigkeitsbewertung von Machine-Learningbasierten Interpretationsalgorithmen für Bewegungsmuster zur intuitiven Maschinensteuerung
No full textEnhancing Life Satisfaction through Eudaimonic, Hedonic, and Combined Interventions: New Training Approaches Relevant to Theory and Practice
No full textIn recent scientific debates, eudaimonia and hedonia have been discussed as either complementary or opposing pathways to well-being. If they are opposites, a combination of the two would not have a positive effect. If they are complementary, their combination is of particular interest. Research to date has often been based on correlational designs that do not allow any conclusions to be drawn about causality. Therefore, we used randomized control designs not only to demonstrate the effectiveness of interventions for eudaimoina and hedonia but also to see whether or not a combination of hedonia and eudaimonia will lead to life satisfaction (full-life effectivity) or even outperforms single-component interventions (full-life superiority). Two randomized controlled studies were conducted with pre-, post- and follow-up measurements. In Study 1 (N = 265), we compared four groups: hedonia training, eudaimonia training, combined training and a control group. In Study 2 (N = 76), we compared three groups: eudaimonia training, combined training and a control group. Results showed positive effects on life satisfaction in the eudaimonia and hedonia groups. The combined training worked (full-life effectivity), although not more so than the single-component trainings (no full-life superiority). The expected mediating role of the art-of-living (a set of individual behavioral strategies) for training effects on life satisfaction was also supported. Results are discussed with reference to the synergetic change model, which offers further ideas to improve combined trainings
Synthesis and application of a hydrophobic polyglutamate bearing a triphenylphosphine group for the orientation of pharmaceutically active compounds and the measurement of residual dipolar couplings
No full textFor structure elucidation purposes, it is highly desirable to partially retain anisotropic observables in high-resolution NMR spectra, as they provide valuable information about the relative configuration, conformation, and dynamics of compounds in solution. Alignment media based on lyotropic liquid crystalline phases formed by α-helical polypeptides can be used to achieve weak solute alignment. We present a novel homopolyglutamate bearing a bulky and hydrophobic triphenylphosphine side chain, which proved to be an excellent alignment medium using chloroform as a co-solvent. We successfully applied the alignment medium for the measurement of residual dipolar couplings (RDCs) of artemisinin, an antimalarial drug, galantamine, which is used to treat Alzheimer's disease, and vincamine, a cerebral vasodilator and potential anti-cancer agent. Excellent agreement between experimental and back-calculated RDCs is obtained, and the enantio-differentiating property of the new medium is demonstrated using the model compound isopinocampheol. Our results show that this alignment medium is of high interest for elucidating compounds characterized by high complexity and relevance in the research field of small molecule pharmaceuticals
Passive investing, active decisions: The DAX index inclusion effect
No full textThe rising popularity of index‐replicating Exchange Traded Funds (ETFs) reflects the broader shift toward passive investing. However, the DAX 40 index incorporates an active component through inclusions and deletions, which affect investor returns. While the short‐term “index inclusion effect” around announcement and inclusion dates is well‐documented, we focus on long‐term post‐rebalancing dynamics. We show that newly included stocks between 2010 and 2023 outperformed the DAX 40 by an average of 33.2% during the 12 months before inclusion but underperformed an average of 36.1% over the subsequent 24 months. This mean reversion can be leveraged via a market‐neutral strategy that shorts newly included stocks on the inclusion date and pairs this with a long DAX ETF position. Maintaining the short for 18 months generates a statistically significant alpha relative to a Fama–French six‐factor asset pricing model, even after accounting for transaction costs. Our study reveals a hidden performance drag in the DAX 40 index, with important implications for passive investors in the index