TY - JOUR A1 - Smith, Wayne A1 - Kotliar, Konstantin A1 - Lammertyn, Leandi A1 - Ramoshaba, Nthai E. A1 - Vilser, Walthard A1 - Huisman, Hugo W. A1 - Schutte, Aletta E. T1 - Retinal vessel caliber and caliber responses in true normotensive black and white adults: The African-PREDICT study JF - Microvascular Research N2 - Purpose Globally, a detrimental shift in cardiovascular disease risk factors and a higher mortality level are reported in some black populations. The retinal microvasculature provides early insight into the pathogenesis of systemic vascular diseases, but it is unclear whether retinal vessel calibers and acute retinal vessel functional responses differ between young healthy black and white adults. Methods We included 112 black and 143 white healthy normotensive adults (20–30 years). Retinal vessel calibers (central retinal artery and vein equivalent (CRAE and CRVE)) were calculated from retinal images and vessel caliber responses to flicker light induced provocation (FLIP) were determined. Additionally, ambulatory blood pressure (BP), anthropometry and blood samples were collected. Results The groups displayed similar 24 h BP profiles and anthropometry (all p > .24). Black participants demonstrated a smaller CRAE (158 ± 11 vs. 164 ± 11 MU, p < .001) compared to the white group, whereas CRVE was similar (p = .57). In response to FLIP, artery maximal dilation was greater in the black vs. white group (5.6 ± 2.1 vs. 3.3 ± 1.8%; p < .001). Conclusions Already at a young age, healthy black adults showed narrower retinal arteries relative to the white population. Follow-up studies are underway to show if this will be related to increased risk for hypertension development. The reason for the larger vessel dilation responses to FLIP in the black population is unclear and warrants further investigation. Y1 - 2020 U6 - http://dx.doi.org/10.1016/j.mvr.2019.103937 SN - 0026-2862 VL - 128 IS - Article 103937 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kotliar, Konstantin A1 - Vilser, Walthatd A1 - Nagel, Edgar A1 - Lanzl, Ines M. T1 - Retinal vessel reaction in response to chromatic flickering light / Kotliar, Konstantin E. ; Vilser, Walthard ; Nagel, Edgar ; Lanzl, Ines M. JF - Graefe's Archive for Clinical and Experimental Ophthalmology. 242 (2004), H. 5 Y1 - 2004 SN - 1435-702X SP - 377 EP - 392 PB - - ER - TY - JOUR A1 - Neumaier, Felix A1 - Kotliar, Konstantin A1 - Haeren, Roel Hubert Louis A1 - Temel, Yasin A1 - Lüke, Jan Niklas A1 - Seyam, Osama A1 - Lindauer, Ute A1 - Clusmann, Hans A1 - Hescheler, Jürgen A1 - Schubert, Gerrit Alexander A1 - Schneider, Toni A1 - Albanna, Walid T1 - Retinal Vessel Responses to Flicker Stimulation Are Impaired in Ca v 2.3-Deficient Mice—An in- vivo Evaluation Using Retinal Vessel Analysis (RVA) JF - Frontiers in Neurology Y1 - 2021 U6 - http://dx.doi.org/10.3389/fneur.2021.659890 VL - 12 SP - 1 EP - 11 PB - Frontiers ER - TY - JOUR A1 - Menzel, C. A1 - Kotliar, Konstantin A1 - Lanzl, I. T1 - Retrospektive Untersuchung jahreszeitlich bedingter Einflussfaktoren auf den Augeninnendruck therapierter Glaukompatienten JF - Der Ophthalmologe Y1 - 2009 SN - 1433-0423 VL - 106 IS - 11 SP - 1006 EP - 1011 PB - - ER - TY - JOUR A1 - Staat, Manfred T1 - Rezension zu: K. Zimmermann, Technische Mechanik – multimedial. Fachbuch Verlag Leipzig (2000) JF - Technische Mechanik Y1 - 2002 SN - 0232-3869 VL - 22 IS - 1 SP - 76 EP - 77 ER - TY - JOUR A1 - Kurulgan Demirci, Eylem A1 - Demirci, Taylan A1 - Linder, Peter A1 - Trzewik, Jürgen A1 - Gierkowski, Jessica Ricarda A1 - Gossmann, Matthias A1 - Kayser, Peter A1 - Porst, Dariusz A1 - Digel, Ilya A1 - Artmann, Gerhard A1 - Temiz Artmann, Aysegül T1 - rhAPC reduces the endothelial cell permeability via a decrease of contractile tensions induced by endothelial cells JF - Journal of Bioscience and Bioengineering N2 - All cells generate contractile tension. This strain is crucial for mechanically controlling the cell shape, function and survival. In this study, the CellDrum technology quantifying cell's (the cellular) mechanical tension on a pico-scale was used to investigate the effect of lipopolysaccharide (LPS) on human aortic endothelial cell (HAoEC) tension. The LPS effect during gram-negative sepsis on endothelial cells is cell contraction causing endothelium permeability increase. The aim was to finding out whether recombinant activated protein C (rhAPC) would reverse the endothelial cell response in an in-vitro sepsis model. In this study, the established in-vitro sepsis model was confirmed by interleukin 6 (IL-6) levels at the proteomic and genomic levels by ELISA, real time-PCR and reactive oxygen species (ROS) activation by florescence staining. The thrombin cellular contraction effect on endothelial cells was used as a positive control when the CellDrum technology was applied. Additionally, the Ras homolog gene family, member A (RhoA) mRNA expression level was checked by real time-PCR to support contractile tension results. According to contractile tension results, the mechanical predominance of actin stress fibers was a reason of the increased endothelial contractile tension leading to enhanced endothelium contractility and thus permeability enhancement. The originality of this data supports firstly the basic measurement principles of the CellDrum technology and secondly that rhAPC has a beneficial effect on sepsis influenced cellular tension. The technology presented here is promising for future high-throughput cellular tension analysis that will help identify pathological contractile tension responses of cells and prove further cell in-vitro models. KW - Cell permeability KW - Cellular force KW - Endothelial cells KW - Recombinant activated protein C KW - Lipopolysaccharide KW - Contractile tension KW - CellDrum Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.jbiosc.2012.03.019 SN - 1347-4421 VL - 113 IS - 2 SP - 212 EP - 219 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kolditz, Melanie A1 - Albin, Thivaharan A1 - Brüggemann, Gert-Peter A1 - Abel, Dirk A1 - Albracht, Kirsten T1 - Robotergestütztes System für ein verbessertes neuromuskuläres Aufbautraining der Beinstrecker JF - at - Automatisierungstechnik N2 - Neuromuskuläres Aufbautraining der Beinstrecker ist ein wichtiger Bestandteil in der Rehabilitation und Prävention von Muskel-Skelett-Erkrankungen. Effektives Training erfordert hohe Muskelkräfte, die gleichzeitig hohe Belastungen von bereits geschädigten Strukturen bedeuten. Um trainingsinduzierte Schädigungen zu vermeiden, müssen diese Kräfte kontrolliert werden. Mit heutigen Trainingsgeräten können diese Ziele allerdings nicht erreicht werden. Für ein sicheres und effektives Training sollen durch den Einsatz der Robotik, Sensorik, eines Regelkreises sowie Muskel-Skelett-Modellen Belastungen am Zielgewebe direkt berechnet und kontrolliert werden. Auf Basis zweier Vorstudien zu möglichen Stellgrößen wird der Aufbau eines robotischen Systems vorgestellt, das sowohl für Forschungszwecke als auch zur Entwicklung neuartiger Trainingsgeräte verwendet werden kann. Y1 - 2016 U6 - http://dx.doi.org/10.1515/auto-2016-0044 SN - 2196-677X VL - 64 IS - 11 SP - 905 EP - 914 PB - De Gruyter CY - Berlin ER - TY - CHAP A1 - Akimbekov, Nuraly S. A1 - Digel, Ilya A1 - Razzaque, Mohammed S. T1 - Role of vitamins in maintaining structure and function of intestinal microbiome T2 - Comprehensive Gut Microbiota N2 - The recent advances in microbiology have shed light on understanding the role of vitamins beyond the nutritional range. Vitamins are critical in contributing to healthy biodiversity and maintaining the proper function of gut microbiota. The sharing of vitamins among bacterial populations promotes stability in community composition and diversity; however, this balance becomes disturbed in various pathologies. Here, we overview and analyze the ability of different vitamins to selectively and specifically induce changes in the intestinal microbial community. Some schemes and regularities become visible, which may provide new insights and avenues for therapeutic management and functional optimization of the gut microbiota. KW - Vitamin A KW - Vitamin B KW - Thiamine KW - Riboflavin KW - Niacin Y1 - 2022 SN - 978-0-12-822036-8 U6 - http://dx.doi.org/10.1016/B978-0-12-819265-8.00043-7 SP - 320 EP - 334 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Frank, T. A1 - Buchwald, D. A1 - Pennekamp, W. A1 - Reber, D. A1 - Sponagel, Stefan A1 - Laszkovics, A. A1 - Weber, Hans-Joachim T1 - Röntgenologische Untersuchung der Strömungseigenschaften funktioneller Komponenten der Herz-Lungen-Maschine JF - Kardiotechnik. 18 (2009), H. 2 Y1 - 2009 SN - 0941-2670 N1 - gedruckt in der Bibliothek unter der Signatur 63 Z 629 SP - 31 EP - 35 ER - TY - JOUR A1 - Frotscher, Ralf A1 - Muanghong, Danita A1 - Dursun, Gözde A1 - Goßmann, Matthias A1 - Temiz Artmann, Aysegül A1 - Staat, Manfred T1 - Sample-specific adaption of an improved electro-mechanical model of in vitro cardiac tissue JF - Journal of Biomechanics N2 - We present an electromechanically coupled computational model for the investigation of a thin cardiac tissue construct consisting of human-induced pluripotent stem cell-derived atrial, ventricular and sinoatrial cardiomyocytes. The mechanical and electrophysiological parts of the finite element model, as well as their coupling are explained in detail. The model is implemented in the open source finite element code Code_Aster and is employed for the simulation of a thin circular membrane deflected by a monolayer of autonomously beating, circular, thin cardiac tissue. Two cardio-active drugs, S-Bay K8644 and veratridine, are applied in experiments and simulations and are investigated with respect to their chronotropic effects on the tissue. These results demonstrate the potential of coupled micro- and macroscopic electromechanical models of cardiac tissue to be adapted to experimental results at the cellular level. Further model improvements are discussed taking into account experimentally measurable quantities that can easily be extracted from the obtained experimental results. The goal is to estimate the potential to adapt the presented model to sample specific cell cultures. KW - hiPS cardiomyocytes KW - Homogenization KW - Hodgkin–Huxley models KW - Frequency adaption KW - Electromechanical modeling KW - Drug simulation KW - Computational biomechanics KW - Cardiac tissue Y1 - 2016 U6 - http://dx.doi.org/10.1016/j.jbiomech.2016.01.039 SN - 0021-9290 (Print) SN - 1873-2380 (Online) VL - 49 IS - 12 SP - 2428 EP - 2435 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rittweger, Jörn A1 - Albracht, Kirsten A1 - Flück, Martin A1 - Ruoss, Severin A1 - Brocca, Lorenza A1 - Longa, Emanuela A1 - Moriggi, Manuela A1 - Seynnes, Olivier A1 - Di Giulio, Irene A1 - Tenori, Leonardo A1 - Vignoli, Alessia A1 - Capri, Miriam A1 - Gelfi, Cecilia A1 - Luchinat, Claudio A1 - Franceschi, Claudio A1 - Bottinelli, Roberto A1 - Cerretelli, Paolo A1 - Narici, Marco T1 - Sarcolab pilot study into skeletal muscle’s adaptation to longterm spaceflight JF - npj Microgravity Y1 - 2018 U6 - http://dx.doi.org/10.1038/s41526-018-0052-1 SN - 2373-8065 VL - 4 IS - 1 SP - 1 EP - 9 PB - Nature Portfolio ER - TY - RPRT A1 - Bhattarai, Aroj A1 - Frotscher, Ralf A1 - Durong, Minh Tuán A1 - Staat, Manfred T1 - Schlussbericht zu BINGO. Optimierung des Systems Netzimplantat-Beckenboden zur therapeutischen Gewebeverstärkung nach der Integraltheorie. Y1 - 2016 N1 - Förderkennzeichen BMBF 03FH073PX2 CY - Aachen ER - TY - CHAP A1 - Waldmann, Christoph A1 - Vera, Jean-Pierre de A1 - Dachwald, Bernd A1 - Strasdeit, Henry A1 - Sohl, Frank A1 - Hanff, Hendrik A1 - Kowalski, Julia A1 - Heinen, Dirk A1 - Macht, Sabine A1 - Bestmann, Ulf A1 - Meckel, Sebastian A1 - Hildebrandt, Marc A1 - Funke, Oliver A1 - Gehrt, Jan-Jöran T1 - Search for life in ice-covered oceans and lakes beyond Earth T2 - 2018 IEEE/OES Autonomous Underwater Vehicle Workshop, Proceedings November 2018, Article number 8729761 N2 - The quest for life on other planets is closely connected with the search for water in liquid state. Recent discoveries of deep oceans on icy moons like Europa and Enceladus have spurred an intensive discussion about how these waters can be accessed. The challenge of this endeavor lies in the unforeseeable requirements on instrumental characteristics both with respect to the scientific and technical methods. The TRIPLE/nanoAUV initiative is aiming at developing a mission concept for exploring exo-oceans and demonstrating the achievements in an earth-analogue context, exploring the ocean under the ice shield of Antarctica and lakes like Dome-C on the Antarctic continent. KW - Planetary exploration KW - Jupiter KW - ice moons KW - underwater vehicle KW - Antarctica Y1 - 2018 U6 - http://dx.doi.org/10.1109/AUV.2018.8729761 ER - TY - CHAP A1 - Loeb, Horst W. A1 - Schartner, Karl-Heinz A1 - Seboldt, Wolfgang A1 - Dachwald, Bernd A1 - Streppel, Joern A1 - Meusemann, Hans A1 - Schülke, Peter T1 - SEP for a lander mission to the jovian moon europa T2 - 57th International Astronautical Congress N2 - Under DLR-contract, Giessen University and DLR Cologne are studying solar-electric propulsion missions (SEP) to the outer regions of the solar system. The most challenging reference mission concerns the transport of a 1.35-tons chemical lander spacecraft into an 80-RJ circular orbit around Jupiter, which would enable to place a 375 kg lander with 50 kg of scientific instruments on the surface of the icy moon "Europa". Thorough analyses show that the best solution in terms of SEP launch mass times thrusting time would be a two-stage EP module and a triple-junction solar array with concentrators which would be deployed step by step. Mission performance optimizations suggest to propel the spacecraft in the first EP stage by 6 gridded ion thrusters, running at 4.0 kV of beam voltage, which would save launch mass, and in the second stage by 4 thrusters with 1.25 to 1.5 kV of positive high voltage saving thrusting time. In this way, the launch mass of the spacecraft would be kept within 5.3 tons. Without a launcher's C3 and interplanetary gravity assists, Jupiter might be reached within about 4 yrs. The spiraling-down into the parking orbit would need another 1.8 yrs. This "large mission" can be scaled down to a smaller one, e.g., by halving all masses, the solar array power, and the number of thrusters. Due to their reliability, long lifetime and easy control, RIT-22 engines have been chosen for mission analysis. Based on precise tests, the thruster performance has been modeled. Y1 - 2006 U6 - http://dx.doi.org/10.2514/6.IAC-06-C4.4.04 N1 - 57th International Astronautical Congress, 02 October 2006 - 06 October 2006, Valencia, Spain. SP - 1 EP - 12 ER - TY - CHAP A1 - Loeb, Horst Wolfgang A1 - Schartner, Karl-Heinz A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - SEP-Sample return from a main belt asteroid T2 - 30th International Electric Propulsion Conference N2 - By DLR-contact, sample return missions to the large main-belt asteroid “19, Fortuna” have been studied. The mission scenario has been based on three ion thrusters of the RIT-22 model, which is presently under space qualification, and on solar arrays equipped with triple-junction GaAs solar cells. After having designed the spacecraft, the orbit-to-orbit trajectories for both, a one-way SEP mission with a chemical sample return and an all-SEP return mission, have been optimized using a combination of artificial neural networks with evolutionary algorithms. Additionally, body-to-body trajectories have been investigated within a launch period between 2012 and 2015. For orbit-to-orbit calculation, the launch masses of the hybrid mission and of the all-SEP mission resulted in 2.05 tons and 1.56 tons, respectively, including a scientific payload of 246 kg. For the related transfer durations 4.14 yrs and 4.62 yrs were obtained. Finally, a comparison between the mission scenarios based on SEP and on NEP have been carried out favouring clearly SEP. Y1 - 2007 SP - 1 EP - 11 ER - TY - CHAP A1 - Tran, Ngoc Trinh A1 - Tran, Thanh Ngoc A1 - Matthies, H. G. A1 - Stavroulakis, G. E. A1 - Staat, Manfred ED - Papadrakakis, M. T1 - Shakedown analysis of plate bending analysis under stochastic uncertainty by chance constrained programming T2 - ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5–10 June 2016 Y1 - 2016 ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - Shakedown analysis of Reissner-Mindlin plates using the edge-based smoothed finite element method T2 - Direct methods for limit states in structures and materials / Dieter Weichert ; Alan Ponter, ed. N2 - This paper concerns the development of a primal-dual algorithm for limit and shakedown analysis of Reissner-Mindlin plates made of von Mises material. At each optimization iteration, the lower bound of the shakedown load multiplier is calculated simultaneously with the upper bound using the duality theory. An edge-based smoothed finite element method (ES-FEM) combined with the discrete shear gap (DSG) technique is used to improve the accuracy of the solutions and to avoid the transverse shear locking behaviour. The method not only possesses all inherent features of convergence and accuracy from ES-FEM, but also ensures that the total number of variables in the optimization problem is kept to a minimum compared with the standard finite element formulation. Numerical examples are presented to demonstrate the effectiveness of the present method. Y1 - 2014 SN - 978-94-007-6826-0 (Print) 978-94-007-6827-7 (Online) U6 - http://dx.doi.org/10.1007/978-94-007-6827-7_5 SP - 101 EP - 117 PB - Springer CY - Dordrecht [u.a.] ER - TY - JOUR A1 - Vu, Duc Khoi A1 - Staat, Manfred T1 - Shakedown analysis of structures made of materials with temperature-dependent yield stress JF - International Journal of Solids and Structures. 44 (2007), H. 13 Y1 - 2007 SN - 0020-7683 SP - 4524 EP - 4540 ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - Shakedown analysis of two dimensional structures by an edge-based smoothed finite element method Y1 - 2010 N1 - ECCM 2010, IV European Conference on Computational Mechanics, Paris, France, May 16-21, 2010. SP - 1 EP - 7 ER - TY - CHAP A1 - Tran, N. T. A1 - Tran, Thanh Ngoc A1 - Matthies, M. G. A1 - Stavroulakis, G. E. A1 - Staat, Manfred T1 - Shakedown Analysis Under Stochastic Uncertainty by Chance Constrained Programming T2 - Advances in Direct Methods for Materials and Structures N2 - In this paper we propose a stochastic programming method to analyse limit and shakedown of structures under uncertainty condition of strength. Based on the duality theory, the shakedown load multiplier formulated by the kinematic theorem is proved actually to be the dual form of the shakedown load multiplier formulated by static theorem. In this investigation a dual chance constrained programming algorithm is developed to calculate simultaneously both the upper and lower bounds of the plastic collapse limit and the shakedown limit. The edge-based smoothed finite element method (ES-FEM) with three-node linear triangular elements is used for structural analysis. Y1 - 2017 SN - 978-3-319-59810-9 U6 - http://dx.doi.org/10.1007/978-3-319-59810-9_6 SP - 85 EP - 103 PB - Springer CY - Cham ER -