TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Anisotrope Ausbreitung und Fokussierung von Beschleunigungswellen in vorgespannten nichtlinearelastischen Scheiben JF - Wellenfokussierung, Kolloquium des SFB 27, RWTH Aachen Y1 - 1985 SP - 140 EP - 158 CY - Aachen ER - TY - THES A1 - Staat, Manfred T1 - Nichtlineare Wellen in elastischen Scheiben Y1 - 1987 N1 - Aachen, Techn. Hochsch., Diss., 1987 CY - Aachen ER - TY - JOUR A1 - Staat, Manfred T1 - Anisotrope Wellenausbreitung in isotropen hyperelastischen Scheiben JF - Zeitschrift für angewandte Mathematik und Mechanik : ZAMM. 67 (1987), H. 4 Y1 - 1987 SN - 0946-8463 SP - T241 EP - T243 ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Wave Propagation and Focussing in Plates JF - Impact loading and dynamic behaviour of materials : Papers presented at the International Conference on Impact Loading and Dynamic Behaviour of Materials, Vol. 2 / Chiem, C. Y.; Kunze, L. (u.a.) [eds] Y1 - 1988 PB - DGM Informationsges. CY - Oberursel ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Zur Problematik tensorieller Verallgemeinerungen einachsiger nichtlinearer Materialgesetze JF - Zeitschrift für angewandte Mathematik und Mechanik : ZAMM. 69 (1989), H. 2 Y1 - 1989 SN - 0946-8463 U6 - http://dx.doi.org/10.1515/9783112553169-006 SP - 73 EP - 81 ER - TY - JOUR A1 - Staat, Manfred A1 - Wolters, J A1 - Bongarts, W. A1 - Hennings, W. (u.a.) T1 - Überarbeitete probabilistisch orientierte Sicherheitsanalyse für den HTR-Modul JF - Jahrestagung Kerntechnik '90 / Kerntechnische Gesellschaft e.V. ; Deutsches Atomforum e.V Y1 - 1990 SP - 143 EP - 146 PB - INFORUM CY - Bonn ER - TY - JOUR A1 - Staat, Manfred T1 - Versagenswahrscheinlichkeit der Primärkreisdruckumschließung eines HTR-Moduls zur Prozeßwärmegewinnung unter Störfallbedingungen bei verschiedenen Versagensmoden Y1 - 1991 N1 - 17. MPA-Seminar : Sicherheit und Verfügbarkeit in der Anlagentechnik mit dem Schwerpunkt Kerntechnik, Stuttgart (1991), 22.1-22.20 ER - TY - JOUR A1 - Staat, Manfred T1 - Versagenswahrscheinlichkeit der Primärkreisdruckumschließung eines HTR-Moduls zur Prozeßwärmegewinnung unter Störfallbedingungen JF - Jahrestagung Kerntechnik '91 / Kerntechnische Gesellschaft e.V. ; Deutsches Atomforum e.V Y1 - 1991 SP - 123 EP - 126 PB - INFORUM CY - Bonn ER - TY - JOUR A1 - Staat, Manfred T1 - Probabilistische Bewertung des bruchmechanischen Verhaltens der Primärkreisdruckumschließung eines HTR-Moduls Y1 - 1992 N1 - 18. MPA-Seminar : Sicherheit und Verfügbarkeit in der Anlagentechnik mit dem Schwerpunkt Kernenergie. Stuttgart (1992), 27.1-27.18 ER - TY - JOUR A1 - Staat, Manfred T1 - Sensitivity of and Influences on the Reliability of an HTR-Module Primary Circuit Pressure Boundary JF - Transactions of the 12th International Conference on Structural Mechanics in Reactor Technology (SMiRT-12) / Kussmaul, K. [ed] Y1 - 1993 SN - 0-444-81515-5 N1 - Vol. M, Paper MG10/2 SP - 147 EP - 152 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Staat, Manfred T1 - Reliability of the Primary Circuit Pressure Boundary of an HTR-Module under Accident Conditions JF - Safety and reliability assessment : an integral approach ; ESREL'93 ; proceedings of the European Safety and Reliability Conference, Munich, Germany, May 10th - 12th 1993 / Kafka, P. [ed] Y1 - 1993 SN - 0-444-81561-9 SP - 331 EP - 342 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Staat, Manfred T1 - Failure probabilities of the primary circuit pressure boundary of an HTR-Module for process heat generation under accident conditions for different failure modes JF - Nuclear Engineering and Design. 144 (1993), H. 1 Y1 - 1993 SN - 0029-5493 SP - 53 EP - 67 ER - TY - JOUR A1 - Staat, Manfred T1 - Reliability of an HTR-module primary circuit pressure boundary Influences, sensitivity, and comparison with a PWR JF - Nuclear Engineering and Design. 158 (1995), H. 2-3 Y1 - 1995 SN - 0029-5493 SP - 333 EP - 340 ER - TY - JOUR A1 - Staat, Manfred T1 - Problems and Chances for Probabilistic Fracture Mechanics in the Analysis of Steel Pressure Boundary Reliability JF - Technical feasibility and reliability of passive safety systems for nuclear power plants. Proceedings of an Advisory Group Meeting held in Jülich, 21-24 November 1994 Y1 - 1996 N1 - IAEA-TECDOC-920 ; Onlinezugriff erfolgt auf die überarb. Ausg. 2006 SP - 43 EP - 55 CY - Vienna ER - TY - JOUR A1 - Staat, Manfred T1 - Probabilistic assessment of the fracture mechanics behaviour of an HTR-module primary circuit pressure boundary JF - Nuclear Engineering and Design. 160 (1996), H. 1-2 Y1 - 1996 SN - 0029-5493 SP - 221 EP - 236 ER - TY - JOUR A1 - Staat, Manfred A1 - Fiorini, G. L. A1 - Lensa, W. von A1 - Burgazzi, L. T1 - Reliability Methods for Passive Safety Functions JF - Proceedings of the SMiRT 14 Post Conference Seminar No 18 on Passive Safety Features in Nuclear Installations Y1 - 1997 CY - Pisa ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis for Plastic Safety of Complex Structures JF - Transactions of the 14th International Conference on Structural Dynamics in Reactor Technology (SMiRT-14) / Livolant, M. [ed] Y1 - 1997 N1 - Vol. B, Paper B02/2 SP - 33 EP - 40 CY - Lyon ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. A1 - Hicken, E.F. T1 - LISA, ein europäisches Projekt zur direkten Berechnung der Tragfähigkeit duktiler Strukturen. Y1 - 1998 N1 - PERMAS–Benutzertagung, 8.–9.10.1998, Stuttgart (1998) ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Structural Reliability Analysis of Elasto-Plastic Structures JF - Safety and reliability : proceedings of ESREL '99, the Tenth European Conference on Safety and Reliability, Munich-Garching, Germany, 13 - 17 September 1999 / Schuëller, G. I.; Kafka, P. [eds] Y1 - 1999 SN - 90-5809-109-0 SP - 513 EP - 518 PB - Balkema CY - Rotterdam ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - FEM-computation of load carrying capacity of highly loaded passive components by direct methods. Heitzer, M. ; Staat, M. JF - Nuclear Engineering and Design. 193 (1999), H. 3 Y1 - 1999 SN - 0029-5493 SP - 349 EP - 358 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Traglastanalyse - ein strukturmechanisches Verfahren zur Beurteilung von gerissenen Bauteilen und Verbindungen JF - Festigkeits- und Bruchverhalten von Fügeverbindungen : 32. Tagung des DVM-Arbeitskreises Bruchvorgänge ; 22. und 23. Februar 2000 in Berlin / Richard, H. A. [Hrsg] Y1 - 2000 N1 - DVM-Bericht 232 SP - 183 EP - 192 PB - Deutscher Verband für Materialforschung und -prüfung CY - Berlin ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Reliability Analysis of Elasto-Plastic Structures under Variable Loads JF - Inelastic analysis of structures under variable loads : theory and engineering applications / Maier, G.; Weichert, D. [ed] Y1 - 2000 SN - 0-7923-6645-X SP - 269 EP - 288 PB - Kluwer Academic Publ. CY - Dordrecht ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Direct FEM approach to design-by-analysis of pressurized components JF - Achema 2000 : Sonderausgabe / Linde. [Hrsg.: Linde AG. Red.: Volker R. Leski] Y1 - 2000 SP - 79 EP - 81 PB - Linde AG CY - Wiesbaden ER - TY - BOOK A1 - Staat, Manfred A1 - Heitzer, M. A1 - Yan, Ai-Min A1 - Khoi, Vu Duc A1 - Nguyen, Dang Hung A1 - Valdoire, F. A1 - Lahousse, A. T1 - Limit Analysis of Defects Y1 - 2000 SN - 0944-2952 N1 - Bericht des Forschungszentrums, Jül-3746, Jülich (2000) PB - Forschungszentrum Jülich CY - Jülich ER - TY - JOUR A1 - Staat, Manfred T1 - Some Achievements of the European Project LISA for FEM Based Limit and Shakedown Analysis JF - Computational mechanics : developments and applications, 2002 : presented at the 2002 ASME Pressure Vessels and Piping Conference, Vancouver, British Columbia, Canada, August 5 - 9. / Badie, N. [ed] Y1 - 2002 SN - 0791846520 N1 - Serie PVP ; vol. 441. SP - 177 EP - 185 PB - American Society of Mechanical Engineers CY - New York ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis with Uncertain Data JF - Stochastic optimization techniques : numerical methods and technical applications / Marti, K. [ed] Y1 - 2002 SN - 3-540-42889-5 SP - 241 EP - 254 PB - Springer CY - Heidelberg 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 - Staat, Manfred A1 - Heitzer, M. A1 - Reiners, H. A1 - Schubert, F. T1 - Shakedown and ratchetting under tension–torsion loadings: analysis and experiments JF - Nuclear Engineering and Design. 225 (2003), H. 1 Y1 - 2003 SN - 0029-5493 SP - 11 EP - 26 ER - TY - JOUR A1 - Staat, Manfred A1 - Schwartz, M. A1 - Lang, H. A1 - Wirtz, K. A1 - Heitzer, M. T1 - Design by Analysis of Pressure Components by non-linear Optimization JF - The 10th International Conference on Pressure Vessel Technology, July 7-10, 2003, Vienna, Austria, Proceedings ICPVT-10 / Zeman, J. L. [ed] Y1 - 2003 SN - 3950152814 SP - 59 EP - 65 PB - ÖGS, Österreichische Gesellschaft für Schweißtechnik CY - Wien ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Probabilistic limit and shakedown problems JF - Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M. Y1 - 2003 SN - 3-00-010001-6 SP - 217 EP - 268 PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - CHAP A1 - Staat, Manfred A1 - Heitzer, M. T1 - Basis reduction technique for limit and shakedown problems T2 - Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M.; Heitzer, M. Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0001-2018112115 SN - 3-00-010001-6 SP - 1 EP - 55 PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - CHAP A1 - Staat, Manfred A1 - Heitzer, Michael ED - Staat, Manfred ED - Heitzer, Michael T1 - Probabilistic limit and shakedown problems T2 - Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems Y1 - 2003 SN - 3-00-010001-6 N1 - NIC Series VL - 15 SP - 217 EP - 268 PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - BOOK A1 - Staat, Manfred A1 - Heitzer, Michael T1 - Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems. Y1 - 2003 SN - 3-00-010001-6 N1 - NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M. PB - John von Neumann Institute for Computing (NIC) CY - Jülich ER - TY - JOUR A1 - Staat, Manfred T1 - Plastic collapse analysis of longitudinally flawed pipes and vessels JF - Nuclear Engineering and Design. 234 (2004), H. 1-3 Y1 - 2004 SN - 0029-5493 SP - 25 EP - 43 ER - TY - JOUR A1 - Staat, Manfred A1 - Kühn, R. A1 - Hauger, W. A1 - Sponagel, Stefan T1 - An Interpretation of Wolff’s Law JF - Biomedizinische Technik. 49 (2004) Y1 - 2004 SN - 0932-4666 N1 - Ergänzungsband 2, Teil 2 SP - 1020 EP - 1021 ER - TY - JOUR A1 - Staat, Manfred A1 - Vu, Duc-Khoi T1 - An Algorithm for Shakedown Analysis for Materials with Temperature Dependent Yield Stress JF - Proceedings in Applied Mathematics and Mechanics (PAMM). 4 (2004), H. 1 Y1 - 2004 SN - 1617-7061 SP - 231 EP - 233 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. A1 - Lang, H. A1 - Wirtz, K. T1 - Direct Finite Element Route for Design-by-Analysis of Pressure Components JF - International Journal of Pressure Vessels and Piping. 82 (2005), H. 1 Y1 - 2005 SN - 0308-0161 SP - 61 EP - 67 ER - TY - JOUR A1 - Staat, Manfred T1 - Local and global collapse pressure of longitudinally flawed pipes and cylindrical vessels JF - International Journal of Pressure Vessels and Piping. 82 (2005), H. 3 Y1 - 2005 SN - 0308-0161 SP - 217 EP - 225 ER - TY - JOUR A1 - Staat, Manfred A1 - Vu, Khoi Duc T1 - Limit loads of circumferentially flawed pipes and cylindrical vessels under internal pressure JF - International Journal of Pressure Vessels and Piping. 83 (2006), H. 3 Y1 - 2006 SN - 0308-0161 SP - 188 EP - 196 ER - TY - JOUR A1 - Staat, Manfred A1 - Vu, Duc-Khoi T1 - Limit analysis of flaws in pressurized pipes and cylindrical vessels. Part I: Axial defects JF - Engineering Fracture Mechanics. 74 (2007), H. 3 Y1 - 2007 SN - 0013-7944 SP - 431 EP - 450 ER - TY - JOUR A1 - Vu, Duc Khoi A1 - Staat, Manfred A1 - Tran, Ich Thinh T1 - Analysis of pressure equipment by application of the primal-dual theory of shakedown JF - Communications in Numerical Methods in Engineering. 23 (2007), H. 3 Y1 - 2007 SN - 1069-8299 SP - 213 EP - 225 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 - Eschweiler, J. A1 - Laack, Walter van A1 - Staat, Manfred T1 - Elektromyographische Untersuchungen zur Kräftigung der Oberschenkelmuskulatur mit einem myoelektrischen Stimulator nach arthroskopischen Eingriffen am Kniegelenk JF - Orthopädische Praxis. 43 (2007), H. 10 Y1 - 2007 SN - 0030-588x SP - 539 EP - 542 ER - TY - JOUR A1 - Staat, Manfred A1 - Baroud, G. A1 - Topcu, M. A1 - Sponagel, Stefan T1 - Soft Materials in Technology and Biology – Characteristics, Properties, and Parameter Identification JF - Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) Y1 - 2008 SN - 978-3-540-75408-4 SP - 253 EP - 315 PB - Springer CY - Berlin ER - TY - JOUR A1 - Vant, Christianne A1 - Staat, Manfred A1 - Baroud, Gamal T1 - Percutaneous Vertebroplasty: A Review of Two Intraoperative Complications JF - Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) Y1 - 2008 SN - 978-3-540-75408-4 SP - 527 EP - 539 PB - Springer CY - Berlin ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Kreißig, R. A1 - Vu, Duc Khoi A1 - Staat, Manfred T1 - Upper bound limit and shakedown analysis of shells using the exact Ilyushin yield surface JF - Computer & Structures. 86 (2008) Y1 - 2008 SN - 0045-7949 SP - 1683 EP - 1695 ER - TY - JOUR A1 - Staat, Manfred A1 - Tran, Thanh Ngoc A1 - Kreißig, R. T1 - Load bearing capacity of thin shell structures made of elastoplastic material by direct methods JF - Technische Mechanik. 28 (2008), H. 3-4 Y1 - 2008 SP - 299 EP - 309 ER - TY - JOUR A1 - Ciobanu, Octavian A1 - Staat, Manfred A1 - Rahimi, Alireza T1 - The use of open source software in biomechanical finite element analysis JF - Buletinul Institutului Politehnic din Iaşi / Universitatea Tehnică Gh. Asachi, Iaşi Secţia 5, Construcţii de maşini = Machine construction = Bulletin of the Polytechnic Institute of Jassy = Izvestija Jasskogo Politechničeskogo Instituta Y1 - 2008 SN - 1011-2855 VL - 54 IS - 7/8 SP - 213 EP - 220 ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Kreißig, R. A1 - Staat, Manfred T1 - Probabilistic limit and shakedown analysis of thin plates and shells JF - Structural safety. 31 (2009), H. 1 Y1 - 2009 SN - 0167-4730 SP - 1 EP - 18 PB - - ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Pham, Phu Tinh A1 - Vu, D. K. A1 - Staat, Manfred T1 - Reliability Analysis of Inelastic Shell Structures Under Variable Loads JF - Limit States of Materials and Structures : Direct Methods / Hrsg. Dieter Weichert; Hrsg. Alan Ponter Y1 - 2009 SN - 978-1-4020-9633-4 SP - 135 EP - 156 PB - Springer Netherland CY - Berlin ER - TY - JOUR A1 - Ullrich, Sebastian A1 - Grottke, Oliver A1 - Rossaint, Rolf A1 - Staat, Manfred A1 - Deserno, Thomas M. A1 - Kuhlen, Torsten T1 - Virtual Needle Simulation with Haptics for Regional Anaesthesia Y1 - 2010 N1 - IEEE Virtual Reality 2010, Workshop on Medical Virtual Environments, Waltham, MA, USA, March 21, 2010 SP - 1 EP - 3 ER - TY - JOUR A1 - Nguyen, N.-H. A1 - Raatschen, Hans-Jürgen A1 - Staat, Manfred T1 - A hyperelastic model of biological tissue materials in tubular organs Y1 - 2010 N1 - ECCM 2010, IV European Conference on Computational Mechanics, Paris, France, May 16-21, 2010. SP - 1 EP - 12 ER - TY - JOUR A1 - Pham, Phu Tinh A1 - Vu, Khoi Duc A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - A primal-dual algorithm for shakedown analysis of elastic-plastic bounded linearly kinematic hardening bodies Y1 - 2010 N1 - ECCM 2010, IV European Conference on Computational Mechanics, Paris, France, May 16-21, 2010. SP - 1 EP - 7 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 - JOUR A1 - Grottke, O. A1 - Braunschweig, T. A1 - Philippen, B. A1 - Gatzweiler, Karl-Heinz A1 - Gronloh, N. A1 - Staat, Manfred A1 - Rossaint, R. A1 - Tolba, R. T1 - A New Model for Blunt Liver Injuries in the Swine JF - European Surgical Research. 44 (2010), H. 2 Y1 - 2010 SN - 1421-9921 SP - 65 EP - 73 ER - TY - JOUR A1 - Staat, Manfred A1 - Sponagel, Stefan A1 - Nguyen, Nhu Huynh T1 - Experiment and material model for soft tissue materials JF - Constitutive models for rubber VI : proceedings of the sixth European Conference on Constitutive Models for Rubber, Dresden, Germany, 7 - 10 September 2009 / eds. Gert Heinrich ... Y1 - 2010 SN - 978-0-415-56327-7 SP - 465 EP - 470 PB - CRC Press CY - Boca Raton [u.a.] ER - TY - JOUR A1 - Doorschodt, B. M. A1 - Schreinemachers, M. C. J. M. A1 - Behbahani, Mehdi A1 - Florquin, S. A1 - Weis, J. A1 - Staat, Manfred A1 - Tolba, R. H. T1 - Hypothermic machine perfusion of kidney grafts: which pressure is preferred JF - Annals of Biomedical Engineering. 39 (2011), H. 3 Y1 - 2011 SN - 1573-9686 SP - 1051 EP - 1059 PB - Springer CY - Berlin ER - TY - JOUR A1 - Staat, Manfred A1 - Vu, Duc Khoi T1 - Limit analysis of flaws in pressurized pipes and cylindrical vessels Part II: Circumferential defects JF - Engineering Fracture Mechanics ; 97(2013), H. 1 N2 - Upper and lower bound theorems of limit analyses have been presented in part I of the paper. Part II starts with the finite element discretization of these theorems and demonstrates how both can be combined in a primal–dual optimization problem. This recently proposed numerical method is used to guide the development of a new class of closed-form limit loads for circumferential defects, which show that only large defects contribute to plastic collapse with a rapid loss of strength with increasing crack sizes. The formulae are compared with primal–dual FEM limit analyses and with burst tests. Even closer predictions are obtained with iterative limit load solutions for the von Mises yield function and for the Tresca yield function. Pressure loading of the faces of interior cracks in thick pipes reduces the collapse load of circumferential defects more than for axial flaws. Axial defects have been treated in part I of the paper. Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.engfracmech.2012.05.017 SN - 0013-7944 VL - 97 SP - 314 EP - 333 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Staat, Manfred A1 - Trenz, Eva A1 - Lohmann, Philipp A1 - Frotscher, Ralf A1 - Klinge, Uwe A1 - Tabaza, Ruth A1 - Kirschner-Hermanns, Ruth T1 - New measurements to compare soft tissue anchoring systems in pelvic floor surgery JF - Journal of Biomedical Materials Research Part B: Applied Biomaterials N2 - Suburethral slings as well as different meshes are widely used treating stress urinary incontinence and prolaps in women. With the development of MiniSlings and special meshes using less alloplastic material anchorage systems become more important to keep devices in place and to put some tension especially on the MiniSlings. To date, there are many different systems of MiniSlings of different companies on the market which differ in the structure of the used meshes and anchors. A new objective measurement method to compare different properties of MiniSling systems (mesh and anchor) is presented in this article. Ballistic gelatine acts as soft tissue surrogate. Significant differences in parameters like pull-out strength of anchors or shrinkage of meshes under loading conditions have been determined. The form and size of the anchors as well as the structural stability of the meshes are decisive for a proper integration. The tested anchorings sytems showed markedly different mechanical function at their respective load bearing capacity. As the stable fixation of the device in tissue is a prerequisite for a permanet reinforcement, the proposed test system permits further optimisation of anchor and mesh devices to improve the success of the surgical treatment Y1 - 2012 U6 - http://dx.doi.org/10.1002/jbm.b.32654 SN - 1552-4981 VL - 100B IS - 4 SP - 924 EP - 933 PB - Wiley CY - Hoboken, NJ ER - TY - JOUR A1 - Novacek, V. A1 - Tran, Thanh Ngoc A1 - Klinge, U. A1 - Tolba, R. H. A1 - Staat, Manfred A1 - Bronson, D. G. A1 - Miesse, A. M. A1 - Whiffen, J. A1 - Turquier, F. T1 - Finite element modelling of stapled colorectal end-to-end anastomosis : Advantages of variable height stapler design JF - Journal of Biomechanics N2 - The impact of surgical staplers on tissues has been studied mostly in an empirical manner. In this paper, finite element method was used to clarify the mechanics of tissue stapling and associated phenomena. Various stapling modalities and several designs of circular staplers were investigated to evaluate the impact of the device on tissues and mechanical performance of the end-to-end colorectal anastomosis. Numerical simulations demonstrated that a single row of staples is not adequate to resist leakage due to non-linear buckling and opening of the tissue layers between two adjacent staples. Compared to the single staple row configuration, significant increase in stress experienced by the tissue at the inner staple rows was observed in two and three rows designs. On the other hand, adding second and/or third staple row had no effect on strain in the tissue inside the staples. Variable height design with higher staples in outer rows significantly reduced the stresses and strains in outer rows when compared to the same configuration with flat cartridge. KW - Variable height stapler design KW - Anastomotic leakage KW - Finite element modelling KW - End-to-end colorectal anastomosis KW - Surgical staplers Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.jbiomech.2012.07.021 SN - 1873-2380 VL - 45 IS - 115 SP - 2693 EP - 2697 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Nguyen, Nhu Huynh A1 - Duong, Minh Tuan A1 - Tran, Thanh Ngoc A1 - Pham, Phu Tinh A1 - Grottke, O. A1 - Tolba, R. A1 - Staat, Manfred T1 - Influence of a freeze–thaw cycle on the stress–stretch curves of tissues of porcine abdominal organs JF - Journal of Biomechanics N2 - The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze–thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze–thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines. KW - Autolysis KW - Decomposition KW - Freeze–thaw process KW - Spleen KW - Liver Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.jbiomech.2012.07.008 SN - 1873-2380 VL - 45 IS - 14 SP - 2382 EP - 2386 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Hasan, Istabrak A1 - Keil, Ludger A1 - Staat, Manfred A1 - Wahl, Gerhard A1 - Bourauel, Christoph T1 - Determination of the frictional coefficient of the implant-antler interface : experimental approach JF - Biomedical Engineering / Biomedizinische Technik N2 - The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5–0.7 and 0.3–0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens. Y1 - 2012 SN - 1862-278X VL - 57 IS - 5 SP - 359 EP - 363 PB - De Gruyter CY - Berlin ER - TY - CHAP A1 - Nix, Yvonne A1 - Frotscher, Ralf A1 - Staat, Manfred ED - Eberhardsteiner, J. T1 - Implementation of the edge-based smoothed extended finite element method T2 - Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012 Y1 - 2012 ER - TY - CHAP A1 - Frotscher, Ralf A1 - Raatschen, Hans-Jürgen A1 - Staat, Manfred ED - Eberhardsteiner, J. T1 - Application of an edge-based smoothed finite element method on geometrically non-linear plates of non-linear material T2 - Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Y1 - 2012 N1 - 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012 ER - TY - CHAP A1 - Duong, Minh Tuan A1 - Nguyen, Nhu Huynh A1 - Staat, Manfred ED - Eberhardsteiner, J. T1 - Numerical stability enhancement of modeling hyperelastic materials T2 - Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Y1 - 2012 N1 - 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012 ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred ED - Eberhardsteiner, J. T1 - A primal-dual shakedown analysis of 3D structures using the face-based smoothed finite element method T2 - Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Y1 - 2012 N1 - 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012 ER - TY - CHAP A1 - Pham, Phu Tinh A1 - Nguyen, Thanh Ngoc A1 - Staat, Manfred T1 - FEM based shakedown analysis of hardening structures T2 - Proceedings International Conference on Advances in Computational Mechanics (ACOME) Y1 - 2012 N1 - International Conference on Advances in Computational Mechanics (ACOME), August 14-16, 2012, Ho Chi Minh City, Vietnam SP - 870 EP - 882 ER - TY - CHAP A1 - Staat, Manfred T1 - Limit and shakedown analysis under uncertainty T2 - Proceedings International Conference on Advances in Computational Mechanics (ACOME) Y1 - 2012 N1 - International Conference on Advances in Computational Mechanics (ACOME), August 14-16, 2012, Ho Chi Minh City, Vietnam SP - 837 EP - 861 ER - TY - CHAP A1 - Frotscher, Ralf A1 - Raatschen, Hans-Jürgen A1 - Staat, Manfred ED - Holzapfel, Gerhard A. T1 - Effectiveness of the edge-based smoothed finite element method applied to soft biological tissues T2 - ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012 Y1 - 2012 SN - 978-3-85125-223-1 PB - Verlag d. Technischen Universität Graz CY - Graz ER - TY - CHAP A1 - Duong, Minh Tuan A1 - Nguyen, Nhu Hunyh A1 - Staat, Manfred T1 - Finite Element Implementation of a 3D Fung-type Model T2 - ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012 Y1 - 2012 SN - 978-3-85125-223-1 PB - Verlag d. Technischen Universität Graz CY - Graz ER - TY - JOUR A1 - Staat, Manfred T1 - Limit and shakedown analysis under uncertainty JF - Tap chi Khoa hoc & ung dung - Dai hoc Ton Duc Thang Y1 - 2012 N1 - = Journal of Applied Sciences - Ton Duc Thang University VL - 19 SP - 45 EP - 47 ER - TY - JOUR A1 - Pham, Phu Tinh A1 - Staat, Manfred T1 - An Upper Bound Algorithm for Limit and Shakedown Analysis of Bounded Linearly Kinematic Hardening Structures JF - Limit State of Materials and Structures : Direct Methods 2. Saxcé, Géry de (Hrsg.) Y1 - 2013 SN - 978-94-007-5424-9 SP - 71 EP - 87 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - An Edge-Based Smoothed Finite Element Method for Primal-Dual Shakedown Analysis of Structures Under Uncertainties JF - Limit State of Materials and Structures : Direct Methods 2. Saxcé, Géry de (Hrsg.) Y1 - 2013 SN - 978-94-007-5424-9 SP - 89 EP - 102 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Linden, A. A1 - Fischöder, M. A1 - Laack, Walter van A1 - Staat, Manfred T1 - Einschränkung von Taluskippung und -vorschub durch Sprunggelenkorthesen nach fibularer Bandruptur JF - OUP Zeitschrift für die orthopädische und unfallchirurgische Praxis N2 - Die fibulare Bandruptur zählt zu einer der am häufigsten auftretenden Verletzungen des Bewegungsapparats. In den meisten Fällen wird heute die konservativ frühfunktionelle Therapie mit Sprunggelenkorthesen allgemein bevorzugt. Im Rahmen der vorliegenden Studie wurden 14 verschiedene Sprunggelenkorthesen im Hinblick auf ihre Einschränkung von Taluskippung und Talusvorschub untersucht. Zur Simulation einer fibularen Bandruptur wurde ein Unterschenkelmodell aus Holz mit Fußteil, mit angelegten Orthesen in einen Scheuba-Halteapparat eingespannt und mit 150 N seitlich sowie anterior-posterior belastet. Anhand der erstellten "gehaltenen" Röntgenaufnahmen konnten Taluskippung und Talusvorschub jeder einzelnen Orthese eindeutig bestimmt werden. Die meisten Orthesen erreichten zufriedenstellende Ergebnisse. Es stellte sich heraus, dass vor allem eine eng anliegende, im Gelenkbereich anatomisch angepasste Form vorteilhaft zu sein scheint. N2 - The ankle sprain is actually one of the most common injuries. Nowadays the conservative pre-functional therapy with ankle braces is generally preferred. In the present study 14 different ankle braces were tested with regard to their ability to constrict the talar tilt and anterior drawer displacement. As part of the tests a wooden model of a foot was used in order to simulate an ankle sprain. This model was clamped in a Scheuba-device with different ankle braces and a force of 150 N was applied to it. The stress radiographs showed different talar tilts and anterior drawers of each brace. Most ankle braces achieved a satisfying result. It has become obvious that a tight fitting and an anatomically designed shape seem to be favourable. T2 - Constraint of talar tilt and anterior drawer by different ankle braces after the rupture of fibular ligaments KW - Sprunggelenkorthesen KW - fibulare Bandruptur KW - Distorsion des oberen Sprunggelenks KW - ankle sprain KW - rupture of the fibular ligament KW - ankle braces Y1 - 2013 SN - 2193-5785 U6 - http://dx.doi.org/10.3238/oup.2013.0306-0309 VL - 2 IS - 6 SP - 306 EP - 309 PB - Deutscher Ärzte-Verl. CY - Köln ER - TY - JOUR A1 - Laack, Walter van A1 - Levers, A. A1 - Staat, Manfred T1 - Gonarthrosetherapie auf Kernspinresonanzbasis mit MBST-Vierjahresbeobachtungen JF - Orthopädische Nachrichten : Zeitung für Orthopädie und Unfallchirurgie. 2013, H. 7/8 Y1 - 2013 SN - 1437-2193 SP - 13 PB - Biermann CY - Köln ER - TY - JOUR A1 - Staat, Manfred T1 - Limit and shakedown analysis under uncertainty JF - International journal of computational methods : IJCM Y1 - 2013 SN - 0219-8762 SP - Publ. online PB - World Scientific Publishing CY - Singapore ER - TY - CHAP A1 - Frotscher, Ralf A1 - Goßmann, Matthias A1 - Temiz Artmann, Aysegül A1 - Staat, Manfred T1 - Simulation of cardiac cell-seeded membranes using the edge-based smoothed FEM T2 - 1st International Conference "Shell and Membrane Theories in Mechanics and Biology: From Macro- to Nanoscale Structures", Minsk, Belarus, Sept. 16-20, 2013 Y1 - 2013 SN - 978-985-553-135-8 SP - 165 EP - 167 PB - Verl. d. Weißruss. Staatl. Univ. CY - Minsk ER - TY - JOUR A1 - Jung, Alexander A1 - Staat, Manfred A1 - Müller, Wolfram T1 - Flight style optimization in ski jumping on normal, large, and ski flying hills JF - Journal of biomechanics Y1 - 2013 SN - 1873-2380 (E-Journal); 0021-9290 (Print) N1 - Corrigendum to “Flight style optimization in ski jumping on normal, large, and ski flying hills” [J. Biomech 47 (2014) 716-722] Journal of Biomechanics, 2018;71:313. VL - Vol. 47 IS - Iss. 3 SP - 716 EP - 722 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Anding, Ralf A1 - Tabaza, Ruth A1 - Staat, Manfred A1 - Trenz, Eva A1 - Lohmann, Philipp A1 - Klinge, Uwe A1 - Kirschner-Hermanns, Ruth T1 - Introducing a method of in vitro testing of different anchoring systems used for female incontinence and prolapse surgery JF - BioMed research international Y1 - 2013 SN - 1110-7251 (E-Journal); 2314-6141 (E-Journal); 1110-7243 (Print); 2314-6133 (Print) VL - Vol. 2013 SP - Article ID 401417 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 - Pham, Phu Tinh A1 - Staat, Manfred T1 - FEM-based shakedown analysis of hardening structures JF - Asia Pacific journal on computational engineering N2 - This paper develops a new finite element method (FEM)-based upper bound algorithm for limit and shakedown analysis of hardening structures by a direct plasticity method. The hardening model is a simple two-surface model of plasticity with a fixed bounding surface. The initial yield surface can translate inside the bounding surface, and it is bounded by one of the two equivalent conditions: (1) it always stays inside the bounding surface or (2) its centre cannot move outside the back-stress surface. The algorithm gives an effective tool to analyze the problems with a very high number of degree of freedom. Our numerical results are very close to the analytical solutions and numerical solutions in literature. Y1 - 2014 U6 - http://dx.doi.org/10.1186/2196-1166-1-4 SN - 2196-1166 (E-Journal) IS - 1 SP - Article No. 4 PB - SpringerOpen CY - Berlin ER - TY - JOUR A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - Stresses produced by different textile mesh implants in a tissue equivalent JF - BioNanoMaterials N2 - Two single-incision mini-slings used for treating urinary incontinence in women are compared with respect to the stresses they produce in their surrounding tissue. In an earlier paper we experimentally observed that these implants produce considerably different stress distributions in a muscle tissue equivalent. Here we perform 2D finite element analyses to compare the shear stresses and normal stresses in the tissue equivalent for the two meshes and to investigate their failure behavior. The results clearly show that the Gynecare TVT fails for increasing loads in a zipper-like manner because it gradually debonds from the surrounding tissue. Contrary to that, the tissue at the ends of the DynaMesh-SIS direct may rupture but only at higher loads. The simulation results are in good agreement with the experimental observations thus the computational model helps to interpret the experimental results and provides a tool for qualitative evaluation of mesh implants. Y1 - 2014 U6 - http://dx.doi.org/10.1515/bnm-2014-0003 SN - 2191-4672 (E-Journal); 2193-066X (E-Journal); 0011-8656 (Print); 1616-0177 (Print); 2193-0651 (Print) VL - 15 IS - 1-2 SP - 25 EP - 30 PB - De Gruyter CY - Berlin ER - TY - CHAP A1 - Knott, Thomas C. A1 - Sofronia, Raluca E. A1 - Gerressen, Marcus A1 - Law, Yuen A1 - Davidescu, Arjana A1 - Savii, George G. A1 - Gatzweiler, Karl-Heinz A1 - Staat, Manfred A1 - Kuhlen, Torsten W. T1 - Preliminary bone sawing model for a virtual reality-based training simulator of bilateral sagittal split osteotomy T2 - Biomedical simulation : 6th International Symposium, ISBMS 2014, Strasbourg, France, October 16-17, 2014 : proceedings (Lecture notes in computer science : vol. 8789) N2 - Successful bone sawing requires a high level of skill and experience, which could be gained by the use of Virtual Reality-based simulators. A key aspect of these medical simulators is realistic force feedback. The aim of this paper is to model the bone sawing process in order to develop a valid training simulator for the bilateral sagittal split osteotomy, the most often applied corrective surgery in case of a malposition of the mandible. Bone samples from a human cadaveric mandible were tested using a designed experimental system. Image processing and statistical analysis were used for the selection of four models for the bone sawing process. The results revealed a polynomial dependency between the material removal rate and the applied force. Differences between the three segments of the osteotomy line and between the cortical and cancellous bone were highlighted. KW - Bone sawing KW - virtual reality KW - training simulator Y1 - 2014 SN - 978-3-319-12057-7 (Online) SN - 978-3-319-12056-0 (Print) U6 - http://dx.doi.org/10.1007/978-3-319-12057-7_1 SP - 1 EP - 10 PB - Springer CY - Cham ER - TY - CHAP A1 - Frotscher, Ralf A1 - Goßmann, Matthias A1 - Raatschen, Hans-Jürgen A1 - Temiz Artmann, Aysegül A1 - Staat, Manfred T1 - Simulation of cardiac cell-seeded membranes using the edge-based smoothed FEM T2 - Shell and membrane theories in mechanics and biology. (Advanced structured materials ; 45) N2 - We present an electromechanically coupled Finite Element model for cardiac tissue. It bases on the mechanical model for cardiac tissue of Hunter et al. that we couple to the McAllister-Noble-Tsien electrophysiological model of purkinje fibre cells. The corresponding system of ordinary differential equations is implemented on the level of the constitutive equations in a geometrically and physically nonlinear version of the so-called edge-based smoothed FEM for plates. Mechanical material parameters are determined from our own pressure-deflection experimental setup. The main purpose of the model is to further examine the experimental results not only on mechanical but also on electrophysiological level down to ion channel gates. Moreover, we present first drug treatment simulations and validate the model with respect to the experiments. Y1 - 2015 SN - 978-3-319-02534-6 ; 978-3-319-02535-3 SP - 187 EP - 212 PB - Springer CY - Heidelberg ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - Uncertainty multimode failure and shakedown analysis of shells T2 - Direct methods for limit and shakedown analysis of structures / eds. Paolo Fuschi ... N2 - This paper presents a numerical procedure for reliability analysis of thin plates and shells with respect to plastic collapse or to inadaptation. The procedure involves a deterministic shakedown analysis for each probabilistic iteration, which is based on the upper bound approach and the use of the exact Ilyushin yield surface. Probabilistic shakedown analysis deals with uncertainties originated from the loads, material strength and thickness of the shell. Based on a direct definition of the limit state function, the calculation of the failure probability may be efficiently solved by using the First and Second Order Reliability Methods (FORM and SORM). The problem of reliability of structural systems (series systems) is handled by the application of a special technique which permits to find all the design points corresponding to all the failure modes. Studies show, in this case, that it improves considerably the FORM and SORM results. KW - Limit analysis KW - Shakedown analysis KW - Reliability analysis KW - Multimode failure KW - Non-linear optimization Y1 - 2015 SN - 978-3-319-12927-3 (print) ; 978-3-319-12928-0 (online) U6 - http://dx.doi.org/10.1007/978-3-319-12928-0_14 SP - 279 EP - 298 PB - Springer CY - Cham ER - TY - JOUR A1 - Frotscher, Ralf A1 - Koch, Jan-Peter A1 - Staat, Manfred T1 - Computational investigation of drug action on human-induced stem cell derived cardiomyocytes JF - Journal of biomechanical engineering Y1 - 2015 U6 - http://dx.doi.org/10.1115/1.4030173 SN - 1528-8951 (E-Journal); 0148-0731 (Print) VL - Vol. 137 IS - iss. 7 SP - 071002-1 EP - 071002-7 PB - ASME CY - New York ER - TY - JOUR A1 - Duong, Minh Tuan A1 - Nguyen, Nhu Huynh A1 - Tran, Thanh Ngoc A1 - Tolba, R. H. A1 - Staat, Manfred T1 - Influence of refrigerated storage on tensile mechanical properties of porcine liver and spleen JF - International biomechanics Y1 - 2015 U6 - http://dx.doi.org/10.1080/23335432.2015.1049295 SN - 2333-5432 VL - Vol. 2 IS - Iss. 1 SP - 79 EP - 88 PB - Taylor & Francis CY - London ER - TY - CHAP A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - An electromechanical model for cardiac tissue constructs T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - CHAP A1 - Bhattarai, Aroj A1 - Frotscher, Ralf A1 - Staat, Manfred T1 - Biomechanical study of the female pelvic floor dysfunction using the finite element method T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - CHAP A1 - Duong, Minh Tuan A1 - Nguyen, N. H. A1 - Staat, Manfred T1 - Modeling and simulation of a growing mass by the Smoothed Finite Element Method (SFEM) T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen, Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - CHAP A1 - Pham, Phu Tinh A1 - Staat, Manfred T1 - A simplification for shakedown analysis of hardening structures T2 - Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon Y1 - 2015 SP - 1 EP - 4 PB - RWTH Aachen University CY - Aachen ER - TY - JOUR A1 - Duong, Minh Tuan A1 - Nguyen, Nhu Huynh A1 - Staat, Manfred T1 - Physical response of hyperelastic models for composite materials and soft tissues JF - Asia pacific journal on computational engineering Y1 - 2015 U6 - http://dx.doi.org/10.1186/s40540-015-0015-x SN - 2196-1166 VL - 2 IS - 3 (December 2015) SP - 1 EP - 18 ER - TY - JOUR A1 - Goßmann, Matthias A1 - Frotscher, Ralf A1 - Linder, Peter A1 - Bayer, Robin A1 - Epple, U. A1 - Staat, Manfred A1 - Temiz Artmann, Aysegül A1 - Artmann, Gerhard T1 - Mechano-pharmacological characterization of cardiomyocytes derived from human induced pluripotent stem cells JF - Cellular physiology and biochemistry N2 - Background/Aims: Common systems for the quantification of cellular contraction rely on animal-based models, complex experimental setups or indirect approaches. The herein presented CellDrum technology for testing mechanical tension of cellular monolayers and thin tissue constructs has the potential to scale-up mechanical testing towards medium-throughput analyses. Using hiPS-Cardiac Myocytes (hiPS-CMs) it represents a new perspective of drug testing and brings us closer to personalized drug medication. Methods: In the present study, monolayers of self-beating hiPS-CMs were grown on ultra-thin circular silicone membranes and deflect under the weight of the culture medium. Rhythmic contractions of the hiPS-CMs induced variations of the membrane deflection. The recorded contraction-relaxation-cycles were analyzed with respect to their amplitudes, durations, time integrals and frequencies. Besides unstimulated force and tensile stress, we investigated the effects of agonists and antagonists acting on Ca²⁺ channels (S-Bay K8644/verapamil) and Na⁺ channels (veratridine/lidocaine). Results: The measured data and simulations for pharmacologically unstimulated contraction resembled findings in native human heart tissue, while the pharmacological dose-response curves were highly accurate and consistent with reference data. Conclusion: We conclude that the combination of the CellDrum with hiPS-CMs offers a fast, facile and precise system for pharmacological, toxicological studies and offers new preclinical basic research potential. KW - Inotropic compounds KW - Pharmacology KW - Ion channels KW - CellDrum KW - Heart tissue culture KW - Induced pluripotent stem cells KW - Cardiac myocytes Y1 - 2016 U6 - http://dx.doi.org/10.1159/000443124 SN - 1421-9778 (Online) SN - 1015-8987 (Print) VL - 38 IS - 3 SP - 1182 EP - 1198 PB - Karger CY - Basel 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 - CHAP A1 - Jung, Alexander A1 - Staat, Manfred A1 - Müller, Wolfram T1 - Effect of wind on flight style optimisation in ski jumping T2 - 15th International Symposium on Computer Simulation in Biomechanics ; July 9th-11th 2015, Edinburgh, UK Y1 - 2016 SP - 53 EP - 54 PB - The University of Edinburgh ; Loughborough University CY - Edinburgh ER - TY - JOUR A1 - Hackl, Michael A1 - Müller, Lars-Peter A1 - Staat, Manfred A1 - Kahmann, Stephanie Lucina A1 - Wegmann, Kilian T1 - Proximal phalangeal neck fractures of the hand — a biomechanical comparison of three fixation techniques JF - Knee surgery, sports traumatology, arthroscopy N2 - Plate osteosynthesis of displaced proximal phalangeal neck fractures of the hand allows early mobilization due to a stable internal fixation. Nevertheless, joint stiffness—because of soft tissue irritation—represents a common complication leading to high complication rates. Del Pinal et al. recently reported promising clinical results for a new, minimally invasive fixation technique with a cannulated headless intramedullary compression screw. Hence, the aim of this study was to compare plate fixation of proximal phalangeal neck fractures to less two less invasive techniques: Crossed k-wire fixation and intramedullary screw fixation. We hypothesized that these fixation techniques provide inferior stability when compared to plate osteosynthesis. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4080-7 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 148 EP - 149 PB - Springer CY - Berlin ER - TY - JOUR A1 - Hackl, Michael A1 - Kahmann, Stephanie Lucina A1 - Wegmann, Kilian A1 - Ries, Christian A1 - Staat, Manfred A1 - Müller, Lars-Peter T1 - Shortening osteotomy of the proximal radius — a treatment option for isolated osteoarthritis of the lateral column of the elbow joint? JF - Knee surgery, sports traumatology, arthroscopy N2 - Treatment of posttraumatic osteoarthritis of the radial column of the elbow joint remains a challenging yet common issue. While partial joint replacement leads to high revision rates, radial head excision has shown to severely increase joint instability. Shortening osteotomy of the radius could be an option to decrease the contact pressure of the radiohumeral joint and thereby pain levels without causing valgus instability. Hence, the aim of this biomechanical study was to evaluate the effects of radial shortening on axial load distribution and valgus stability of the elbow joint. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4080-7 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 128 EP - 129 PB - Springer CY - Berlin ER - TY - JOUR A1 - Hackl, Michael A1 - Leschinger, T. A1 - Staat, Manfred A1 - Müller, Lars-Peter A1 - Wegmann, Kilian T1 - Reconstruction of the interosseous membrane in the Essex Lopresti lesion — a biomechanical evaluation JF - Knee surgery, sports traumatology, arthroscopy N2 - Surgical reconstruction of the interosseous membrane (IOM) could restore longitudinal forearm stability to avoid persisting disability due to capituloradial and ulnocarpal impingement in Essex Lopresti lesions. This biomechanical study aimed to assess longitudinal forearm stability of intact specimens, after sectioning of the IOM and after reconstruction with a TightRope construct using either a single or double bundle technique. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4080-7 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 130 EP - 131 PB - Springer CY - Berlin ER - TY - JOUR A1 - Wegmann, Kilian A1 - Hackl, Michael A1 - Staat, Manfred A1 - Mayer, Katharina A1 - Müller, Lars-Peter T1 - Double plate osteosynthesis of proximal ulna fractures: biomechanical and clinical results JF - Knee surgery, sports traumatology, arthroscopy N2 - While plate fixation of proximal ulna fractures might lead to superior clinical results compared to tension band wiring, regular plates represent an established risk factor for wound complications. The olecranon double plates (Medartis, Basel, CH) might decrease complications related to the osteosynthesis because of their low profile and better anatomical fit. This study aimed to evaluate the biomechanical performance and clinical results of the olecranon double plates. Y1 - 2016 U6 - http://dx.doi.org/10.1007/s00167-016-4079-0 SN - 0942-2056 VL - Volume 24 IS - Supplement 1 SP - 58 EP - 59 PB - Springer CY - Berlin ER - TY - CHAP A1 - Bhattarai, Aroj A1 - Staat, Manfred ED - Erni, Daniel T1 - Female pelvic floor dysfunction: progress weakening of the support system T2 - 1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen N2 - The structure of the female pelvic floor (PF) is an inter-related system of bony pelvis,muscles, pelvic organs, fascias, ligaments, and nerves with multiple functions. Mechanically, thepelvic organ support system are of two types: (I) supporting system of the levator ani (LA) muscle,and (II) the suspension system of the endopelvic fascia condensation [1], [2]. Significantdenervation injury to the pelvic musculature, depolimerization of the collagen fibrils of the softvaginal hammock, cervical ring and ligaments during pregnancy and vaginal delivery weakens thenormal functions of the pelvic floor. Pelvic organ prolapse, incontinence, sexual dysfunction aresome of the dysfunctions which increases progressively with age and menopause due toweakened support system according to the Integral theory [3]. An improved 3D finite elementmodel of the female pelvic floor as shown in Fig. 1 is constructed that: (I) considers the realisticsupport of the organs to the pelvic side walls, (II) employs the improvement of our previous FEmodel [4], [5] along with the patient based geometries, (III) incorporates the realistic anatomy andboundary conditions of the endopelvic (pubocervical and rectovaginal) fascia, and (IV) considersvarying stiffness of the endopelvic fascia in the craniocaudal direction [3]. Several computationsare carried out on the presented computational model with healthy and damaged supportingtissues, and comparisons are made to understand the physiopathology of the female PF disorders. Y1 - 2016 U6 - http://dx.doi.org/10.17185/duepublico/40821 SP - 11 EP - 12 PB - Universität Duisburg-Essen CY - Duisburg ER -