@inproceedings{FrotscherStaat2015,
  author    = {Frotscher, Ralf and Staat, Manfred},
  title     = {An electromechanical model for cardiac tissue constructs},
  series = {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},
  booktitle = {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},
  publisher = {RWTH Aachen University},
  address   = {Aachen},
  organization    = {ECCOMAS Young Investigators Conference <3, 2015, Aachen>},
  pages     = {1 -- 4},
  year      = {2015},
  language  = {en}
}
@article{ColomboDriraFrotscheretal.2022,
  author    = {Colombo, Daniele and Drira, Slah and Frotscher, Ralf and Staat, Manfred},
  title     = {An element-based formulation for ES-FEM and FS-FEM models for implementation in standard solid mechanics finite element codes for 2D and 3D static analysis},
  series = {International Journal for Numerical Methods in Engineering},
  volume    = {124},
  journal   = {International Journal for Numerical Methods in Engineering},
  number    = {2},
  publisher = {Wiley},
  address   = {Chichester},
  issn      = {1097-0207},
  doi       = {10.1002/nme.7126},
  pages     = {402 -- 433},
  year      = {2022},
  abstract  = {Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element.},
  language  = {en}
}
@inproceedings{FrotscherRaatschenStaat2012,
  author    = {Frotscher, Ralf and Raatschen, Hans-J{\"u}rgen and Staat, Manfred},
  title     = {Application of an edge-based smoothed finite element method on geometrically non-linear plates of non-linear material},
  series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@inproceedings{BhattaraiFrotscherStaat2015,
  author    = {Bhattarai, Aroj and Frotscher, Ralf and Staat, Manfred},
  title     = {Biomechanical study of the female pelvic floor dysfunction using the finite element method},
  series = {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},
  booktitle = {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},
  publisher = {RWTH Aachen University},
  address   = {Aachen},
  organization    = {ECCOMAS Young Investigators Conference <3, 2015, Aachen>},
  pages     = {1 -- 4},
  year      = {2015},
  language  = {en}
}
@incollection{BhattaraiFrotscherStaat2018,
  author    = {Bhattarai, Aroj and Frotscher, Ralf and Staat, Manfred},
  title     = {Computational Analysis of Pelvic Floor Dysfunction},
  series = {Women's Health and Biomechanics},
  booktitle = {Women's Health and Biomechanics},
  publisher = {Springer},
  address   = {Cham},
  isbn      = {978-3-319-71574-2},
  doi       = {10.1007/978-3-319-71574-2_17},
  pages     = {217 -- 230},
  year      = {2018},
  abstract  = {Pelvic floor dysfunction (PFD) is characterized by the failure of the levator ani (LA) muscle to maintain the pelvic hiatus, resulting in the descent of the pelvic organs below the pubococcygeal line. This chapter adopts the modified Humphrey material model to consider the effect of the muscle fiber on passive stretching of the LA muscle. The deformation of the LA muscle subjected to intra-abdominal pressure during Valsalva maneuver is compared with the magnetic resonance imaging (MRI) examination of a nulliparous female. Numerical result shows that the fiber-based Humphrey model simulates the muscle behavior better than isotropic constitutive models. Greater posterior movement of the LA muscle widens the levator hiatus due to lack of support from the anococcygeal ligament and the perineal structure as a consequence of birth-related injury and aging. Old and multiparous females with uncontrolled urogenital and rectal hiatus tend to develop PFDs such as prolapse and incontinence.},
  language  = {en}
}
@article{FrotscherKochStaat2015,
  author    = {Frotscher, Ralf and Koch, Jan-Peter and Staat, Manfred},
  title     = {Computational investigation of drug action on human-induced stem cell derived cardiomyocytes},
  series = {Journal of biomechanical engineering},
  volume    = {Vol. 137},
  journal   = {Journal of biomechanical engineering},
  number    = {iss. 7},
  publisher = {ASME},
  address   = {New York},
  issn      = {1528-8951 (E-Journal); 0148-0731 (Print)},
  doi       = {10.1115/1.4030173},
  pages     = {071002-1 -- 071002-7},
  year      = {2015},
  language  = {en}
}
@inproceedings{FrotscherRaatschenStaat2012,
  author    = {Frotscher, Ralf and Raatschen, Hans-J{\"u}rgen and Staat, Manfred},
  title     = {Effectiveness of the edge-based smoothed finite element method applied to soft biological tissues},
  series = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  booktitle = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  editor    = {Holzapfel, Gerhard A.},
  publisher = {Verlag d. Technischen Universit{\"a}t Graz},
  address   = {Graz},
  isbn      = {978-3-85125-223-1},
  year      = {2012},
  language  = {en}
}
@phdthesis{Frotscher2016,
  author    = {Frotscher, Ralf},
  title     = {Electromechanical modeling and simulation of thin cardiac tissue constructs - smoothed FEM applied to a biomechanical plate problem},
  year      = {2016},
  language  = {en}
}
@inproceedings{NixFrotscherStaat2012,
  author    = {Nix, Yvonne and Frotscher, Ralf and Staat, Manfred},
  title     = {Implementation of the edge-based smoothed extended finite element method},
  series = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012},
  booktitle = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@article{GossmannFrotscherLinderetal.2016,
  author    = {Goßmann, Matthias and Frotscher, Ralf and Linder, Peter and Bayer, Robin and Epple, U. and Staat, Manfred and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard},
  title     = {Mechano-pharmacological characterization of cardiomyocytes derived from human induced pluripotent stem cells},
  series = {Cellular physiology and biochemistry},
  volume    = {38},
  journal   = {Cellular physiology and biochemistry},
  number    = {3},
  publisher = {Karger},
  address   = {Basel},
  issn      = {1421-9778 (Online)},
  doi       = {10.1159/000443124},
  pages     = {1182 -- 1198},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}