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When deep hole drilling problematic aluminum materials, the high ductility and adhesion tendency of these materials lead to the formation of built-up edges, long chips and material adhesions on the tool. This can not only cause rapid tool breakage, but also lead to significant damage to the borehole wall surface. In previous work, it has already been shown that these problems were avoided during vibration-assisted drilling with short tools. Compared to conventional drilling, in vibration-assisted drilling the feed motion is superimposed with a sinusoidal oscillation with a high amplitude and a low frequency resulting in a kinematic cut interruption and the generation of separated chips. The aim of this work is to investigate the extent to which the above mentioned problems encountered in conventional deep hole drilling of aluminum materials can be reduced by vibration-assisted deep hole drilling. To achieve this aim, experiments were carried out in conventional and vibration-assisted deep hole drilling. The chip geometry, feed forces, straightness deviation, surface temperatures and the surface quality of the borehole wall were used as evaluation criteria to compare both processes. It was demonstrated that the formation of built-up edges and material adhesions is avoided by vibration-assisted deep hole drilling. This results in a better surface quality of the borehole wall, what indicates less friction within the borehole due to the generation of small and separated instead of long chips. Since heat generation in vibration-assisted drilling is much lower than in conventional deep hole drilling, boreholes close to the workpiece surface were realized.

Zusammenfassung Kühlschmierstoff (KSS)-strömungen werden in Schleifprozessen eingesetzt, um Schleifbrand am Werkstück zu verhindern. Bislang wurde die KSS-Zufuhr heuristisch optimiert. Um eine zielgerichtete KSS-Strömungsoptimierung zu ermöglichen, wird erstmals die optische schleifscheibennahe Messung von KSS-Strömungsfeldern mittels Particle Image Velocimetry (PIV) und durch Nachverfolgung von Mustern in Schattenwurfbildern untersucht. Als erster Schritt wird an der rotierenden Schleifscheibe, jedoch ohne die Bearbeitung eines Werkstücks, gemessen. Beide Messmethoden liefern vergleichbare Ergebnisse, wobei nahe der Schleifscheibenoberfläche mittels PIV Messwerte mit geringerer Messunsicherheit erzielt werden. Mit dem verwendeten Messaufbau lassen sich mittels PIV Geschwindigkeiten in einem Abstand zwischen 0 cm bis 2 cm und mittels Schattenwurf zwischen 0 cm bis 5 cm zur Schleifscheibenoberfläche messen. Im Ergebnis konnte erstmals der für die Kühlleistung relevante Parameter des Geschwindigkeitsverhältnisses zwischen KSS-Anströmung und Schleifscheibenoberflächengeschwindigkeit in situ gemessen werden. Es wurde festgestellt, dass eine aus der Literatur bekannte Verringerung der Kühleffizienz ab einem Geschwindigkeitsverhältnis von 0,8 mit einem Abprallen des KSS-Strahls beim Auftreffen auf die Schleifscheibe korreliert. In zukünftigen Untersuchungen ist zu klären, wie sich die hier gewonnenen Erkenntnisse zur Messfähigkeit und zum Strömungsverhalten auf den Schleifprozess mit Werkstück übertragen lassen.

Low frequency vibration assisted drilling (LFVAD) is an important cutting process, especially for hard-to-machine materials and materials that tend to produce long chips. In LFVAD the continuous axial tool movement in feed direction is superimposed with a sinusoidal oscillation of the tool. Due to the vibratory movement in axial direction an interrupted cut is enforced leading to the generation of comparatively small chips. In the present study, a chip formation simulation utilizing DEFORM for predicting thrust force and drilling torque was set up aiming at an optimization of LFVAD of the titanium alloy Ti6Al4V by means of modifications of the vibratory tool movement. In order to reduce computation times an initial borehole topography was generated utilizing a kinematic model of the process prior to the chip formation simulation. The simulation results regarding the time-dependent thrust force and drilling torque are compared with measurements. The results show that the modification of the oscillation mode can significantly decrease the maximum thrust force and the torque. Thus the finite element simulation of the process enables a predictive optimization of oscillation modes in LFVAD.

Graphical abstract, Highlights • Intrinsically disordered proteins/protein regions (IDPs/IDPRs) are emerging drug targets. • Lack of fast methods hinders the discovery of inhibitors for IDPs/ IDPRs. • Fast and inexpensive structure-based approaches have been developed. • The developed methods were applied to succesfully design inhibitors targeting the disordered tail of histone H4 and H2A. • The presented methods can be widely used to identify inhibitors for other IDPs/IDPRs., A growing body of research has demonstrated that targeting intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs) is feasible and represents a new trending strategy in drug discovery. However, the number of inhibitors targeting IDPs/IDPRs is increasing slowly due to limitations of the methods that can be used to accelerate the discovery process. We have applied structure-based methods to successfully develop the first peptidic inhibitor (HIPe - Histone Inhibitory Peptide) that targets histone H4 that are released from NETs (Neutrophil Extracellular Traps). HIPe binds stably to the disordered N-terminal tail of histone H4, thereby preventing histone H4-induced cell death. Recently, by utilisation of the same state-of-the-art approaches, we have developed a novel peptidic inhibitor (CHIP - Cyclical Histone H2A Interference Peptide) that binds to NET-resident histone H2A, which results in a blockade of monocyte adhesion and consequently reduction in atheroprogression. Here, we present comprehensive details on the computational methods utilised to design and develop HIPe and CHIP. We have exploited protein–protein complexes as starting structures for rational peptide design and then applied binding free energy methods to predict and prioritise binding strength of the designed peptides with histone H4 and H2A. By doing this way, we have modelled only around 20 peptides and from these were able to select 4–5 peptides, from a total of more than a trillion candidate peptides, for functional characterisation in different experiments. The developed computational protocols are generic and can be widely used to design and develop novel inhibitors for other disordered proteins.

During the past years “rock batteries” have become increasingly relevant for the storage of renewable energy sources, such as wind and solar energy, because of their economic and ecological advantages with respect to previously more common materials for thermal energy storage (TES) such as salt. In rock-based TES systems, thermal energy is stored in packed-bed rock using air as heat transfer fluid. We investigated three different rock types with respect to changes in thermomechanical properties after different numbers of thermal cycles, Ruhr sandstone (Oberste quarry in Dortmund - Germany), basalt (commercial MTV basalt) and Calanca gneiss. Cylindrical samples were heated to 800°C within 11,5 h before temperature was kept constant for another 30 min and then decreased within 11,5 h. Samples were thermomechanically investigated before thermal treatment, and again after 1, 3, 7 and 15 cycles. Additionally, two samples of each rock type were subjected to a thermal cycle with a maximum temperature of 450°C and to 1000°C, respectively, at a heating/cooling rate corresponding to that of the samples heated to 800°C. Samples were characterised with respect to ultrasound wave velocity, bulk density, thermal conductivity, thermal diffusivity, uniaxial compressive strength, splitting tensile strength, mineral content (X-ray powder diffraction) and microstructure (thin section analysis). Samples of basalt could not withstand the standard heating rate. The samples crushed into small pieces also when heating rates were reduced and at a maximum heating temperature of 800°C. For sandstone and gneiss, the ultrasound wave velocity, bulk density, thermal conductivity, thermal diffusivity, uniaxial compressive strength and splitting tensile strength decreased systematically with increasing number of cycles, while the maximum reduction occurred after the first cycle and the relative reduction was similar between both rocks. Microstructural analysis indicated an increase in crack density and minor mineralogical changes upon heating. Both rocks, Ruhr sandstone and Calanca gneiss, appear suitable for TES, but Calanca gneiss is less suitable for temperatures above 800°C due to a significant reduction in bulk density and uniaxial compressive strength when heated to 1000°C. Also, its anisotropy and anisotropic response to heating can lead to preferred flow paths of the heat transfer fluid. Ruhr sandstone maintains a high uniaxial compressive strength of about 100 MPa even after 15 cycles while thermal capacity was only slightly reduced or even increased, and can be recommended for use in high temperature TES. This study is the outcome of a research-oriented teaching program at Ruhr-University Bochum within the Geoscience curriculum for students with focus on Engineering Geology. Student authors (Fränzer to Thomas) are listed in alphabetical order.

The present study examines cross-cultural differences in people’s concept of lying with regard to the question of whether lying requires an agent to say something they believe to be false. While prominent philosophical views maintain that lying entails that a person explicitly expresses a believed-false claim, recent research suggests that people’s concept of lying might also include certain kinds of deception that are communicated more indirectly. An important drawback of previous empirical work on this topic is that only few studies have investigated people’s concept of lying in non-Western samples. In the present study, we compare people’s intuitions about lying with indirect deceptions (i.e., presuppositions, conversational implicatures, and non-verbal actions) in a sample of N = 255 participants from Russia and N = 300 participants from the United Kingdom. Our findings show a strong degree of similarity between lie ratings of participants from Russia and the United Kingdom, with both samples holding it possible for agents to lie with deceptive statements and actions that do not involve the agent saying something they believe to be false.

For industrial grinding processes, the workpiece cooling by metalworking fluids, which strongly influences the workpiece surface layer quality, is not yet fully understood. This leads to high efforts for the empirical determination of suitable cooling parameters, increasing the part manufacturing costs. To close the knowledge gap, a measurement method for the metalworking fluid flow field near the grinding wheel is desired. However, the varying curved surfaces of the liquid phase result in unpredictable light deflections and reflections, which impede optical flow measurements. In order to investigate the yet unknown optical measurement capabilities achievable under these conditions, shadowgraphy in combination with a pattern correlation technique and particle image velocimetry (PIV) are applied in a grinding machine. The results show that particle image velocimetry enables flow field measurements inside the laminar metalworking fluid jet, whereby the shadowgraph imaging velocimetry complements these measurements since it is in particular suitable for regions with spray-like flow regimes. As a conclusion, optical flow field measurements of the metalworking fluid flow in a running grinding machine are shown to be feasible.

Im DFG-Schwerpunktprogramm SPP 2231 „FluSimPro – Effizientes Kühlen, Schmieren, Transportieren“ steht die Entwicklung effizienter Kühlkonzepte im Vordergrund. Die Forschungspartner – das Institut für Spanende Fertigung (ISF) und Leibniz-Institut für Werkstofforientierte Technologien (IWT) – wollen damit zur Weiterentwicklung industrierelevanter Fertigungsverfahren wie dem Wendel- und Ejektortiefbohren beitragen.

Since the cooling mechanism of industrial grinding is not yet fully understood, a measurement of the coolant liquid flow field near the grinding wheel is desired. However, the curved surfaces of the liquid phase result in unpredictable light deflections and reflections, which impedes optical flow measurements. In order to obtain qualitative and quantitative information regarding the flow velocity field of the coolant liquid, shadowgraphy in combination with a pattern correlation technique as well as particle image velocimetry are applied in a grinding machine and studied with respect to their measurement capabilities. Particle image velocimetry enables flow measurements inside the laminar coolant jet, whereby the shadowgraph imaging velocimetry complements these measurements and is in particular suitable for spray-like flow regimes. As a result, optical flow field measurements of the coolant flow in a grinding machine are shown to be feasible, which is required to understand the flow mechanisms that affect the grinding cooling process.

International audience; The perpetuation of inflammation is an important pathophysiological contributor to the global medical burden. Chronic inflammation is promoted by non-programmed cell death1,2; however, how inflammation is instigated, its cellular and molecular mediators, and its therapeutic value are poorly defined. Here we use mouse models of atherosclerosis-a major underlying cause of mortality worldwide-to demonstrate that extracellular histone H4-mediated membrane lysis of smooth muscle cells (SMCs) triggers arterial tissue damage and inflammation. We show that activated lesional SMCs attract neutrophils, triggering the ejection of neutrophil extracellular traps that contain nuclear proteins. Among them, histone H4 binds to and lyses SMCs, leading to the destabilization of plaques; conversely, the neutralization of histone H4 prevents cell death of SMCs and stabilizes atherosclerotic lesions. Our data identify a form of cell death found at the core of chronic vascular disease that is instigated by leukocytes and can be targeted therapeutically.

In her seminal attack on modern moral philosophy, G. E. M. Anscombe claims that Kant's ‘rule about universalizable maxims is useless without stipulations as to what shall count as a relevant description of an action with a view to constructing a maxim about it’. Although this so-called problem of relevant descriptions has received considerable attention in the literature, there is little agreement on how it should be understood or solved. My aim in this paper is, first, to clarify the problem by clearing up several misunderstandings, and, second, to show that the problem is rooted in a standard assumption about Kant's stance on the scope of moral principles—an assumption that precludes its solution. I argue that the problem consists in the fact that Kant's formula of universal law seems to stand in need of an account of moral sensibility that does not render the formula superfluous. But, as my discussion of existing solutions reveals, there can be no such account. Instead, I propose a dissolution: we should think of the formula of universal law itself as Kant's account of moral sensibility. In order to do so, we must reject the standard assumption that a principle is universal if and only if it holds for all instances of the action type that it specifies.