TY - JOUR A1 - Dienst, Karl-Jakob T1 - Bewegungsgruppen projektiv-metrischer Ebenen von Char. 2 JF - Journal für die reine und angewandte Mathematik Y1 - 1971 SN - 0075-4102 U6 - https://doi.org/10.1515/crll.1971.250.130 VL - 250 SP - 130 EP - 140 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Behbahani, Mehdi A1 - Spillner, Jan A1 - Kopp, Rüdiger A1 - Finocchiaro, Thomas T1 - Assistierte Zirkulation : ein Überblick aus klinischer Sicht = Assisted circulation: an overview from a clinical perspective / Spillner, Jan ; Kopp, Rüdiger ; Finocchiaro, Thomas ; Behbahani, Mehdi ; Rossaint, Rolf ; Steinseifer, Ulrich ; Behr, Marek ; Au JF - Biomedizinische Technik / Biomedical Engineering. 54 (2009), H. 5 Y1 - 2009 SN - 0013-5585 N1 - Printausgabe in der Bereichsbibliothek Jülich vorhanden : 63 Z 471 SP - 255 EP - 267 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Meliß, Michael A1 - Oesterwind, Dieter A1 - Voß, Alfred T1 - Non-nuclear and non-fossil energy resources and their possibilities for future power generation JF - Kerntechnik N2 - It must be stressed that the assessment of the exploitation possibilities of the energy resources discussed in this paper requires further studies. With this proviso, the situation can be provisionally summarised as follows: The total potential of known geothermal steam sources is only 64 GW. Geothermal energy could therefore only make a significant contribution to covering the worldwide power needs if we succeed in exploiting dry geothermal reservoirs. Exploitation of tidal energy is limited to a few geographically favourable locations. The power generation potential at these locations is only about 64 GW. An important drawback of tidal power is discontinuous power generation. Large scale exploitation of wind, wave and glacier energy, and of ocean heat, requires solution of a number of technological problems. The environmental effects of exploitation of these energy resources are to some extent of a qualitatively different nature from those of operation of fossil-fuel-fired and of nuclear power plants. The scanty knowledge in this area often results in these effects being underestimated. In any case, however, it would be deliberately misleading to postulate that any form of power generation is possible without some detrimental effects on the environment. It may be stated in conclusion that, owing to their small potential or to the as yet insufficiently advanced technological development, none of the energy resources discussed in this paper can make a significant contribution to the solution of middle-term energy supply problems, i.e., to a rapid replacement of mineral oil and natural gas. Y1 - 1975 U6 - https://doi.org/10.18419/opus-8093 SN - 0932-3902 N1 - Printausg. in der Bibliothek vorhanden: 63 ZS 010-1975 VL - 17 IS - 7 SP - 301 EP - 306 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Meißen, Ralf A1 - Krischer, C. T1 - Elektronische Fernsehlesehilfe für hochgradig sehbehinderte JF - Biomedical Engineering / Biomedizinische Technik Y1 - 1978 U6 - https://doi.org/10.1515/bmte.1978.23.s1.220 VL - 23 IS - s1 SP - 220 EP - 221 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Fissabre, Anke T1 - Dachterrassen der Renaissance – „Cosa più maravigliosa che gl’orti pensili di Babbilonia“ JF - Architectura : Zeitschrift für Geschichte der Baukunst Y1 - 2011 SN - 0044-863X VL - 41 IS - 1 SP - 27 EP - 46 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Bhattarai, Aroj A1 - Jabbari, Medisa A1 - Anding, Ralf A1 - Staat, Manfred T1 - Surgical treatment of vaginal vault prolapse using different prosthetic mesh implants: a finite element analysis JF - tm - Technisches Messen N2 - Particularly multiparous elderly women may suffer from vaginal vault prolapse after hysterectomy due to weak support from lax apical ligaments. A decreased amount of estrogen and progesterone in older age is assumed to remodel the collagen thereby reducing tissue stiffness. Sacrocolpopexy is either performed as open or laparoscopic surgery using prosthetic mesh implants to substitute lax ligaments. Y-shaped mesh models (DynaMesh, Gynemesh, and Ultrapro) are implanted in a 3D female pelvic floor finite element model in the extraperitoneal space from the vaginal cuff to the first sacral (S1) bone below promontory. Numerical simulations are conducted during Valsalva maneuver with weakened tissues modeled by reduced tissue stiffness. Tissues are modeled as incompressible, isotropic hyperelastic materials whereas the meshes are modeled either as orthotropic linear elastic or as isotropic hyperlastic materials. The positions of the vaginal cuff and the bladder base are calculated from the pubococcygeal line for female pelvic floor at rest, for prolapse and after repair using the three meshes. Due to mesh mechanics and mesh pore deformation along the loaded direction, the DynaMesh with regular rectangular mesh pores is found to provide better mechanical support to the organs than the Gynemesh and the Ultrapro with irregular hexagonal mesh pores. Insbesondere ältere, mehrgebährende Frauen leiden häufiger an einem Scheidenvorfall nach einer Hysterektomie aufgrund der schwachen Unterstützung durch laxe apikale Bänder. Es wird angenommen, dass eine verringerte Menge an Östrogen und Progesteron im höheren Alter das Kollagen umformt, wodurch die Gewebesteifigkeit reduziert wird. Die Sakrokolpopexie ist eine offene oder laparoskopische Operation, die mit prothetischen Netzimplantaten durchgeführt wird, um laxe Bänder zu ersetzen. Y-förmige Netzmodelle (DynaMesh, Gynemesh und Ultrapro) werden in einem 3D-Modell des weiblichen Beckenbodens im extraperitonealen Raum vom Vaginalstumpf bis zum Promontorium implantiert. Numerische Simulationen werden während des Valsalva-Manövers mit geschwächtem Gewebe durchgeführt, das durch eine reduzierte Gewebesteifigkeit modelliert wird. Die Gewebe werden als inkompressible, isotrop hyperelastische Materialien modelliert, während die Netze entweder als orthotrope linear elastische oder als isotrope hyperlastische Materialien modelliert werden. Die Positionen des Vaginalstumpfs, der Blase und der Harnröhrenachse werden anhand der Pubococcygeallinie aus der Ruhelage, für den Prolaps und nach der Reparatur unter Verwendung der drei Netze berechnet. Aufgrund der Netzmechanik und der Netzporenverformung bietet das DynaMesh mit regelmäßigen rechteckigen Netzporen eine bessere mechanische Unterstützung und eine Neupositionierung des Scheidengewölbes, der Blase und der Urethraachse als Gynemesh und Ultrapro mit unregelmäßigen hexagonalen Netzporen. Y1 - 2018 U6 - https://doi.org/10.1515/teme-2017-0115 SN - 2196-7113 VL - 85 IS - 5 SP - 331 EP - 342 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Birgel, Stefan A1 - Leschinger, Tim A1 - Wegmann, Kilian A1 - Staat, Manfred T1 - Calculation of muscle forces and joint reaction loads in the shoulder area via an OpenSim based computer model JF - tm - Technisches Messen N2 - Using the OpenSim software and verified anatomical data, a computer model for the calculation of biomechanical parameters is developed and used to determine the effect of a reattachment of the Supraspinatus muscle with a medial displacement of the muscle attachment point, which may be necessary for a rupture of the supraspinatus tendon. The results include the influence of the operation on basic biomechanical parameters such as the lever arm, as well as the calculated the muscle activations for the supraspinatus and deltoid. In addition, the influence on joint stability is examined by an analysis of the joint reaction force. The study provides a detailed description of the used model, as well as medical findings to a reattachment of the supraspinatus. Mit der Software OpenSim und überprüften anatomischen Daten wird ein Computermodell zur Berechnung von biomechanischen Parametern entwickelt und genutzt, um den Effekt einer Refixierung des Supraspinatusmuskels mit einer medialen Verschiebung des Muskelansatzpunktes zu ermitteln, wie sie unter anderem nach einem Riss der Supraspinatussehne notwendig sein kann. Die Ergebnisse umfassen hierbei den Einfluss der Operation auf grundlegende biomechanische Parameter wie den Hebelarm sowie die berechneten Muskelaktivierungen für den Supraspinatus und Deltoideus. Zusätzlich wird der Einfluss auf die Gelenkstabilität betrachtet und durch eine Analyse der Gelenkreaktionskraft untersucht. Die Studie bietet eine detaillierte Beschreibung des genutzten Modells, sowie medizinische Erkenntnisse zu einer Refixierung des Supraspinatus. Y1 - 2018 U6 - https://doi.org/10.1515/teme-2017-0114 SN - 2196-7113 VL - 85 IS - 5 SP - 321 EP - 330 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Weigand, Christoph T1 - Defining Precisions for Reliable Measurement and Estimation Procedures JF - Economic Quality Control. 24 (2009), H. 1 Y1 - 2009 SN - 0940-5151 SP - 5 EP - 33 PB - De Gruyter 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 - https://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 - JOUR A1 - Engelmann, Ulrich M. A1 - Buhl, Eva Miriam A1 - Baumann, Martin A1 - Schmitz-Rode, Thomas A1 - Slabu, Ioana T1 - Agglomeration of magnetic nanoparticles and its effects on magnetic hyperthermia JF - Current Directions in Biomedical Engineering Y1 - 2017 U6 - https://doi.org/10.1515/cdbme-2017-0096 SN - 2364-5504 VL - 3 IS - 2 SP - 457 EP - 460 PB - De Gruyter CY - Berlin ER -