Mechanical Characterisation of Cables in Different Loading Directions

The mechanical characterisation of cables can help improving the production and lifetime of various products, for example a robotic arm. Cables however form a class of composite structures, that is highly anisotropic and dissipates energy due to the reorientation of its constituents which is superimposed by the dissipation due to the deformation of the polymer components. Cables also have a degree of randomness in their structure. Moreover, the stiffness in one loading direction is coupled to the stiffness in another loading direction. In this work, experimental investigations on the mechanical properties of the cables are presented. An experimental setup has been constructed to test the cables in tensile, torsion and the bending directions individually as well as coupled to each other. Free bending tests were conducted where axial forces were compensated during the bending to dissociate the tensile and the bending properties of the cables. To apply larger tensile and torsional loads on cables a commercial testing device was also used. To characterise the influence of bending on torsion, free bending tests were conducted with a combination of torsional load. Thus, a complete mechanical characterisation of a cable is presented

Follow Me If You Want to Live - Understanding the Influence of Human-Like Design on Users’ Perception and Intention to Comply with COVID-19 Education Chatbots

Following recommendations and complying with behavioral attitudes is one major key in overcoming global pandemics, such as COVID-19. As the World Health Organization (WHO) highlights, there is an increased need to follow hygiene standards to prevent infections and in reducing the risk of infections transmissions (World-Health-Organization, 2021). This urgent need offers new use cases of digital services, such as conversational agents that educate and inform individuals about relevant counter measurements. Specifically, due to the increased fatigue in the population in the context of COVID-19, (Franzen and Wöhner, 2021), CAs can play a vital role in supporting and attaining user’s behavior. We conducted an experiment (n=116) to analyze the effect of a human-like-design CA on the intention to comply. Our results show a significant impact of a human-like design on the perception of humanness, source credibility, and trust, which are all (directly or indirectly) drivers of the intention to comply

Eng+ | Ethics For Sustainable Development In Engineering Programmes A Praxis Report Of Tu Berlin’s Think Tank Technology Reflection

Many technical universities alike, TU Berlin is in a future-oriented process of programme transformation to invite a holistic perspective on technology which includes critical thinking and ethical reflection. To this end, TU Berlin recently issued a general study guideline calling for an orientation of all programmes toward sustainable development. Accordingly, students should know about the historical, social and cultural contexts of science and technology and learn to reflect on the ethical consequences of their actions. Together with training in good scientific practice, this content should comprise 12 ECTS in each respective BA and MA programme. With only minor integration of this content in the current curricula to date, this transformation presents a significant challenge since courses need to be realigned as well as replaced. To find an answer, TU Berlin’s engineering faculty initiated a think tank in spring 2022, bringing together students, teachers and administration to search for ways of integrating ethics as well as science reflection and technology reflection to foster sustainable development. In our contribution we present a first outcome, namely the integration framework ENG+ for programme design which allows for the incorporation of ethics and strengthening of core values such as diversity, sustainability, and good scientific practice. In the ENG+ framework, we introduce the strategies of advancing and complementing as well as six corresponding measures for integration – emphasising, empowering, embedding, enabling, enriching, and encountering. We explain how they jointly contribute to the overarching ENG+ concept which brings together ethical reflection and sustainable development

Voltage-dependent structural changes of the membrane-bound anion channel hVDAC1 probed by SEIRA and electrochemical impedance spectroscopy

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The voltage-dependent anion channel (VDAC) is a transmembrane protein that regulates the transfer of metabolites between the cytosol and the mitochondrium. Opening and partial closing of the channel is known to be driven by the transmembrane potential viaa mechanism that is not fully understood. In this work, we employed a spectroelectrochemical approach to probe the voltage-induced molecular structure changes of human VDAC1 (hVDAC1) embedded in a tethered bilayer lipid membrane on a nanostructured Au electrode. The model membrane consisted of a mixed self-assembled monolayer of 6-mercaptohexanol and (cholesterylpolyethylenoxy)thiol, followed by the deposition of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine vesicles including hVDAC1. The stepwise assembly of the model membrane and the incorporation of hVDAC1 were monitored by surface enhanced infrared absorption and electrochemical impedance spectroscopy. Difference spectra allowed for identifying the spectral changes which may be associated with the transition from the open to the “closed” states by shifting the potential above or below the transmembrane potential determined to beca.0.0 Vvs.the open circuit potential. These spectral changes were interpreted on the basis of the orientation- and distance-dependent IR enhancement and indicate alterations of the inclination angle of the β-strands as crucial molecular events, reflecting an expansion or contraction of the β-barrel pore. These protein structural changes that do not confirm nor exclude the reorientation of the α-helix are either directly induced by the electric field or a consequence of a potential-dependent repulsion or attraction of the bilayer.DFG, EXC 314, Unifying Concepts in CatalysisDFG, SFB 803, Funktionalität kontrolliert durch Organisation in und zwischen Membrane