TY - JOUR A1 - Reger, Vitali A1 - Kuhnhenne, Markus A1 - Ebbert, Thiemo A1 - Hachul, Helmut A1 - Blanke, Tobias A1 - Döring, Bernd T1 - Nutzung erneuerbarer Energien durch thermische Aktivierung von Komponenten aus Stahl JF - Stahlbau N2 - Die Versorgung von Neubauten soll möglichst weitgehend unabhängig von fossilen Energieträgern erfolgen. Erneuerbare Energien spielen dafür eine gewichtige Rolle. Eine gute Möglichkeit, erneuerbare Energien ohne viel zusätzlichen Aufwand nutzbar zu machen, ist, bereits vorhandenen Komponenten im Gebäude zusätzliche Funktionen zu geben. Hier kann bspw. die Fassade oder das Dach solarthermisch aktiviert oder durch Fotovoltaikmodule ergänzt werden. Auch Tiefgründungen können neben der statischen Funktion noch eine geothermische Funktion zur Aufnahme oder Abgabe von Wärme erhalten. Neben der Erzeugung bietet sich auch für die Verteilung der Wärme oder Kälte im Gebäude die Integration in Bauteile an. Hier kann bspw. der Boden durch eine Fußbodenheizung oder die Decke durch Deckenstrahlplatten aktiviert werden. Im Rahmen der Veröffentlichung wird auf die thermische Aktivierung von Stahlkomponenten eingegangen. Es wird eine Lösung vorgestellt, die vorgehängte hinterlüftete Stahlfassade (VHF) solarthermisch zu aktivieren. Außerdem werden zwei Möglichkeiten zur geothermischen Aktivierung von Tiefgründungen mittels Stahlpfählen gezeigt. Zuletzt wird ein System zur thermischen Aktivierung von Stahltrapezprofilen an der Decke erläutert, welches Wärme zuführen oder bei Bedarf abführen kann. Y1 - 2020 U6 - https://doi.org/10.1002/stab.202000031 SN - 1437-1049 VL - 2020 IS - Volume 89, Issue 6512-519 SP - 512 EP - 519 PB - Ernst & Sohn CY - Berlin ER - TY - JOUR A1 - Wild, Dominik A1 - Schrezenmeier, Johannes A1 - Czupalla, Markus A1 - Förstner, Roger T1 - Thermal Characterization of additive manufactured Integral Structures for Phase Change Applications JF - 2020 International Conference on Environmental Systems N2 - “Infused Thermal Solutions” (ITS) introduces a method for passive thermal control to stabilize structural components thermally without active heating and cooling systems, by using phase change material (PCM) in combination with lattice – both embedded into an additive manufactured integral structure. The technology is currently under development. This paper presents the results of the thermal property measurements performed on additive manufactured ITS breadboards. Within the breadboard campaigns key characteristics of the additive manufactured specimens were derived: Mechanical parameters: specimen impermeability, minimum wall thickness, lattice structure, subsequent heat treatment. Thermal properties: thermo-optical surface properties of the additive manufactured raw material, thermal conductivity and specific heat capacity measurements. As a conclusion the paper introduces an overview of potential ITS hardware applications, expected to increase the thermal performance. Y1 - 2020 PB - Texas Tech University ER - TY - JOUR A1 - Raffeis, Iris A1 - Adjei-Kyeremeh, Frank A1 - Vroomen, Uwe A1 - Westhoff, Elmar A1 - Bremen, Sebastian A1 - Hohoi, Alexandru A1 - Bührig-Polaczek, Andreas T1 - Qualification of a Ni-Cu alloy for the laser powder bed fusion process (LPBF): Its microstructure and mechanical properties JF - Applied Sciences N2 - As researchers continue to seek the expansion of the material base for additive manufacturing, there is a need to focus attention on the Ni–Cu group of alloys which conventionally has wide industrial applications. In this work, the G-NiCu30Nb casting alloy, a variant of the Monel family of alloys with Nb and high Si content is, for the first time, processed via the laser powder bed fusion process (LPBF). Being novel to the LPBF processes, optimum LPBF parameters were determined, and hardness and tensile tests were performed in as-built conditions and after heat treatment at 1000 °C. Microstructures of the as-cast and the as-built condition were compared. Highly dense samples (99.8% density) were achieved after varying hatch distance (80 µm and 140 µm) with scanning speed (550 mm/s–1500 mm/s). There was no significant difference in microhardness between varied hatch distance print sets. Microhardness of the as-built condition (247 HV0.2) exceeded the as-cast microhardness (179 HV0.2.). Tensile specimens built in vertical (V) and horizontal (H) orientations revealed degrees of anisotropy and were superior to conventionally reported figures. Post heat treatment increased ductility from 20% to 31% (V), as well as from 16% to 25% (H), while ultimate tensile strength (UTS) and yield strength (YS) were considerably reduced. Y1 - 2020 U6 - https://doi.org/10.3390/app10103401 SN - 2076-3417 N1 - Special Issue Materials Development by Additive Manufacturing Techniques VL - 10 IS - Art. 3401 SP - 1 EP - 15 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bayer, Robin A1 - Temiz Artmann, Aysegül A1 - Digel, Ilya A1 - Falkenstein, Julia A1 - Artmann, Gerhard A1 - Creutz, Till A1 - Hescheler, Jürgen T1 - Mechano-pharmacological testing of L-Type Ca²⁺ channel modulators via human vascular celldrum model JF - Cellular Physiology and Biochemistry N2 - Background/Aims: This study aimed to establish a precise and well-defined working model, assessing pharmaceutical effects on vascular smooth muscle cell monolayer in-vitro. It describes various analysis techniques to determine the most suitable to measure the biomechanical impact of vasoactive agents by using CellDrum technology. Methods: The so-called CellDrum technology was applied to analyse the biomechanical properties of confluent human aorta muscle cells (haSMC) in monolayer. The cell generated tensions deviations in the range of a few N/m² are evaluated by the CellDrum technology. This study focuses on the dilative and contractive effects of L-type Ca²⁺ channel agonists and antagonists, respectively. We analyzed the effects of Bay K8644, nifedipine and verapamil. Three different measurement modes were developed and applied to determine the most appropriate analysis technique for the study purpose. These three operation modes are called, particular time mode" (PTM), "long term mode" (LTM) and "real-time mode" (RTM). Results: It was possible to quantify the biomechanical response of haSMCs to the addition of vasoactive agents using CellDrum technology. Due to the supplementation of 100nM Bay K8644, the tension increased approximately 10.6% from initial tension maximum, whereas, the treatment with nifedipine and verapamil caused a significant decrease in cellular tension: 10nM nifedipine decreased the biomechanical stress around 6,5% and 50nM verapamil by 2,8%, compared to the initial tension maximum. Additionally, all tested measurement modes provide similar results while focusing on different analysis parameters. Conclusion: The CellDrum technology allows highly sensitive biomechanical stress measurements of cultured haSMC monolayers. The mechanical stress responses evoked by the application of vasoactive calcium channel modulators were quantified functionally (N/m²). All tested operation modes resulted in equal findings, whereas each mode features operation-related data analysis. Y1 - 2020 U6 - https://doi.org/10.33594/000000225 SN - 1421-9778 VL - 54 SP - 371 EP - 383 PB - Cell Physiol Biochem Press CY - Düsseldorf ER - TY - JOUR A1 - Digel, Ilya A1 - Kern, Inna A1 - Geenen, Eva-Maria A1 - Akimbekov, Nuraly S. T1 - Dental plaque removal by ultrasonic toothbrushes JF - dentistry journal N2 - With the variety of toothbrushes on the market, the question arises, which toothbrush is best suited to maintain oral health? This thematic review focuses first on plaque formation mechanisms and then on the plaque removal effectiveness of ultrasonic toothbrushes and their potential in preventing oral diseases like periodontitis, gingivitis, and caries. We overviewed the physical effects that occurred during brushing and tried to address the question of whether ultrasonic toothbrushes effectively reduced the microbial burden by increasing the hydrodynamic forces. The results of published studies show that electric toothbrushes, which combine ultrasonic and sonic (or acoustic and mechanic) actions, may have the most promising effect on good oral health. Existing ultrasonic/sonic toothbrush models do not significantly differ regarding the removal of dental biofilm and the reduction of gingival inflammation compared with other electrically powered toothbrushes, whereas the manual toothbrushes show a lower effectiveness. Y1 - 2020 U6 - https://doi.org/10.3390/dj8010028 SN - 2304-6767 VL - 8 IS - 28 SP - 1 EP - 13 PB - MDPI CY - Basel ER - TY - JOUR A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Marino, Matthew A1 - Bil, Cees T1 - Wind-tunnel and CFD investigations of UAV landing gears and turrets – Improvements in empirical drag estimation JF - Aerospace Science and Technology N2 - This paper analyzes the drag characteristics of several landing gear and turret configurations that are representative of unmanned aircraft tricycle landing gears and sensor turrets. A variety of these components were constructed via 3D-printing and analyzed in a wind-tunnel measurement campaign. Both turrets and landing gears were attached to a modular fuselage that supported both isolated components and multiple components at a time. Selected cases were numerically investigated with a Reynolds-averaged Navier-Stokes approach that showed good accuracy when compared to wind-tunnel data. The drag of main gear struts could be significantly reduced via streamlining their cross-sectional shape and keeping load carrying capabilities similar. The attachment of wheels introduced interference effects that increased strut drag moderately but significantly increased wheel drag compared to isolated cases. Very similar behavior was identified for front landing gears. The drag of an electro-optical and infrared sensor turret was found to be much higher than compared to available data of a clean hemisphere-cylinder combination. This turret drag was merely influenced by geometrical features like sensor surfaces and the rotational mechanism. The new data of this study is used to develop simple drag estimation recommendations for main and front landing gear struts and wheels as well as sensor turrets. These recommendations take geometrical considerations and interference effects into account. Y1 - 2020 U6 - https://doi.org/10.1016/j.ast.2020.106306 SN - 1270-9638 VL - 107 IS - Art. 106306 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Akimbekov, Nuraly S. A1 - Digel, Ilya A1 - Sherelkhan, Dinara K. A1 - Lutfor, Afzalunnessa B. A1 - Razzaque, Mohammed S. T1 - Vitamin D and the Host-Gut Microbiome: A Brief Overview JF - Acta Histochemica et Cytochemica N2 - There is a growing body of evidence for the effects of vitamin D on intestinal host-microbiome interactions related to gut dysbiosis and bowel inflammation. This brief review highlights the potential links between vitamin D and gut health, emphasizing the role of vitamin D in microbiological and immunological mechanisms of inflammatory bowel diseases. A comprehensive literature search was carried out in PubMed and Google Scholar using combinations of keywords “vitamin D,” “intestines,” “gut microflora,” “bowel inflammation”. Only articles published in English and related to the study topic are included in the review. We discuss how vitamin D (a) modulates intestinal microbiome function, (b) controls antimicrobial peptide expression, and (c) has a protective effect on epithelial barriers in the gut mucosa. Vitamin D and its nuclear receptor (VDR) regulate intestinal barrier integrity, and control innate and adaptive immunity in the gut. Metabolites from the gut microbiota may also regulate expression of VDR, while vitamin D may influence the gut microbiota and exert anti-inflammatory and immune-modulating effects. The underlying mechanism of vitamin D in the pathogenesis of bowel diseases is not fully understood, but maintaining an optimal vitamin D status appears to be beneficial for gut health. Future studies will shed light on the molecular mechanisms through which vitamin D and VDR interactions affect intestinal mucosal immunity, pathogen invasion, symbiont colonization, and antimicrobial peptide expression. Y1 - 2020 U6 - https://doi.org/10.1267/ahc.20011 SN - 1347-5800 VL - 53 IS - 3 SP - 33 EP - 42 PB - Japan Society of Histochemistry and Cytochemistry CY - Osaka ER - TY - JOUR A1 - Köhler, Klemens A1 - Wolf, Martin R. T1 - Organisatorische Maßnahmen zu Erhöhung der IT Sicherheit – Empfehlungen aus der Perspektive der Konflikttheorie N2 - Die NATO definiert den Cyberspace als die "Umgebung, die durch physische und nicht-physische Bestandteile zum Speichern, Ändern, und Austauschen von Daten mit Hilfe von Computer-Netzwerken" [NATO CCDCOE]. Darüber hinaus ist es ein Medium menschlicher Interaktion. IT Angriffe sind feindselige, nichtkooperative Interaktionen, die mittels Konflikttheorie beschrieben werden können. Durch die Anwendung dieses Gedankengebäudes auf IT Sicherheit von Organisationen können eine Reihe von Verbesserungen in Unternehmen identifiziert werden. Y1 - 2020 IS - Preprint ER - TY - JOUR A1 - Bung, Daniel Bernhard A1 - Crookston, Brian M. A1 - Valero, Daniel T1 - Turbulent free-surface monitoring with an RGB-D sensor: the hydraulic jump case JF - Journal of Hydraulic Research Y1 - 2020 U6 - https://doi.org/10.1080/00221686.2020.1844810 SN - 1814-2079 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Marinkovic, Marko A1 - Butenweg, Christoph T1 - Earthquake-proof system for masonry infills in RC frame structures JF - International Journal of Masonry Research and Innovation Y1 - 2020 U6 - https://doi.org/10.1504/IJMRI.2020.106328 SN - 2056-9467 VL - 5 IS - 2 SP - 185 EP - 208 PB - Inderscience Enterprises CY - Olney, Bucks ER -