@article{StaatHeitzer1999, author = {Staat, Manfred and Heitzer, M.}, title = {FEM-computation of load carrying capacity of highly loaded passive components by direct methods. Heitzer, M. ; Staat, M.}, series = {Nuclear Engineering and Design. 193 (1999), H. 3}, journal = {Nuclear Engineering and Design. 193 (1999), H. 3}, isbn = {0029-5493}, pages = {349 -- 358}, year = {1999}, language = {en} } @article{BaaderBoxbergChenetal.2023, author = {Baader, Fabian and Boxberg, Marc S. and Chen, Qian and F{\"o}rstner, Roger and Kowalski, Julia and Dachwald, Bernd}, title = {Field-test performance of an ice-melting probe in a terrestrial analogue environment}, series = {Icarus}, journal = {Icarus}, number = {409}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.icarus.2023.115852}, pages = {Artikel 115852}, year = {2023}, abstract = {Melting probes are a proven tool for the exploration of thick ice layers and clean sampling of subglacial water on Earth. Their compact size and ease of operation also make them a key technology for the future exploration of icy moons in our Solar System, most prominently Europa and Enceladus. For both mission planning and hardware engineering, metrics such as efficiency and expected performance in terms of achievable speed, power requirements, and necessary heating power have to be known. Theoretical studies aim at describing thermal losses on the one hand, while laboratory experiments and field tests allow an empirical investigation of the true performance on the other hand. To investigate the practical value of a performance model for the operational performance in extraterrestrial environments, we first contrast measured data from terrestrial field tests on temperate and polythermal glaciers with results from basic heat loss models and a melt trajectory model. For this purpose, we propose conventions for the determination of two different efficiencies that can be applied to both measured data and models. One definition of efficiency is related to the melting head only, while the other definition considers the melting probe as a whole. We also present methods to combine several sources of heat loss for probes with a circular cross-section, and to translate the geometry of probes with a non-circular cross-section to analyse them in the same way. The models were selected in a way that minimizes the need to make assumptions about unknown parameters of the probe or the ice environment. The results indicate that currently used models do not yet reliably reproduce the performance of a probe under realistic conditions. Melting velocities and efficiencies are constantly overestimated by 15 to 50 \% in the models, but qualitatively agree with the field test data. Hence, losses are observed, that are not yet covered and quantified by the available loss models. We find that the deviation increases with decreasing ice temperature. We suspect that this mismatch is mainly due to the too restrictive idealization of the probe model and the fact that the probe was not operated in an efficiency-optimized manner during the field tests. With respect to space mission engineering, we find that performance and efficiency models must be used with caution in unknown ice environments, as various ice parameters have a significant effect on the melting process. Some of these are difficult to estimate from afar.}, language = {en} } @article{NovacekTranKlingeetal.2012, author = {Novacek, V. and Tran, Thanh Ngoc and Klinge, U. and Tolba, R. H. and Staat, Manfred and Bronson, D. G. and Miesse, A. M. and Whiffen, J. and Turquier, F.}, title = {Finite element modelling of stapled colorectal end-to-end anastomosis : Advantages of variable height stapler design}, series = {Journal of Biomechanics}, volume = {45}, journal = {Journal of Biomechanics}, number = {115}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380}, doi = {10.1016/j.jbiomech.2012.07.021}, pages = {2693 -- 2697}, year = {2012}, abstract = {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.}, language = {en} } @article{DachwaldSchmidtSeboldtetal.2003, author = {Dachwald, Bernd and Schmidt, Tanja D. and Seboldt, Wolfgang and Auweter-Kurtz,}, title = {Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika}, publisher = {-}, pages = {1 -- 9}, year = {2003}, language = {en} } @article{ScholzLeyDachwaldetal.2010, author = {Scholz, A. and Ley, Wilfried and Dachwald, Bernd and Miau, J. J. and Juang, J. C.}, title = {Flight results of the COMPASS-1 picosatellite mission}, series = {Acta Astronautica. 67 (2010), H. 9-10}, journal = {Acta Astronautica. 67 (2010), H. 9-10}, isbn = {0094-5765}, pages = {1289 -- 1298}, year = {2010}, language = {en} } @article{JungStaatMueller2013, author = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram}, title = {Flight style optimization in ski jumping on normal, large, and ski flying hills}, series = {Journal of biomechanics}, volume = {Vol. 47}, journal = {Journal of biomechanics}, number = {Iss. 3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380 (E-Journal); 0021-9290 (Print)}, pages = {716 -- 722}, year = {2013}, language = {en} } @article{ArtmannHueckRossiteretal.2008, author = {Artmann, Gerhard and Hueck, Isgard S. and Rossiter, Katharine and Schmid-Sch{\"o}nbein, Geert W.}, title = {Fluid Shear Attenuates Endothelial Pseudopodia Formation into the Capillary Lumen / Hueck, Isgard S. ; Rossiter, Katharine ; Artman, Gerhard M. ; Schmid-Sch{\"o}nbein, Geert W.}, series = {Microcirculation. 15 (2008), H. 6}, journal = {Microcirculation. 15 (2008), H. 6}, isbn = {1549-8719}, pages = {531 -- 542}, year = {2008}, language = {en} } @article{DigelDemirciTemizArtmannetal.2004, author = {Digel, Ilya and Demirci, Taylan and Temiz Artmann, Ayseg{\"u}l and Nishikawa, K.}, title = {Free Radical Nature of the Bactericidal Effect of Plasma-Generated Cluster Ions (PCIs)}, series = {Biomedizinische Technik. 49 (2004), H. Erg.-Bd. 2}, journal = {Biomedizinische Technik. 49 (2004), H. Erg.-Bd. 2}, isbn = {0932-4666}, pages = {982 -- 983}, year = {2004}, language = {en} } @article{StadlerDigelEmbsetal.2009, author = {Stadler, Andreas M. and Digel, Ilya and Embs, Jan P. and Unruh, Tobias and Tehei, M. and Zaccai, G. and B{\"u}ldt, G. and Artmann, Gerhard}, title = {From powder to solution : Hydration dependence of human hemoglobin dynamics correlated to body temperature}, series = {Biophysical Journal. 96 (2009), H. 12}, journal = {Biophysical Journal. 96 (2009), H. 12}, publisher = {Cell Press}, address = {Cambridge, Mass.}, isbn = {0006-3495}, pages = {5073 -- 5081}, year = {2009}, language = {en} } @article{ArtmannZang1990, author = {Artmann, Gerhard and Zang, Werner}, title = {Fully automatic measurement of rheologic parameters of red blood cells = Laborautomat zur Messung mechanischer Eigenschaften roter Blutzellen}, series = {Biomedizinische Technik = Biomedical engineering. 35 (1990), H. Suppl. 3}, journal = {Biomedizinische Technik = Biomedical engineering. 35 (1990), H. Suppl. 3}, isbn = {0013-5585}, pages = {94 -- 96}, year = {1990}, language = {en} } @article{KotliarNagelVilseretal.2008, author = {Kotliar, Konstantin and Nagel, Edgar and Vilser, Walthard and Lanzl, Ines M.}, title = {Functional in vivo assessment of retinal artery microirregularities in glaucoma / Kotliar, Konstantin E. ; Nagel, Edgar ; Vilser, Walthard ; Lanzl, Ines M.}, series = {Acta Ophthalmologica. 86 (2008), H. 4}, journal = {Acta Ophthalmologica. 86 (2008), H. 4}, publisher = {-}, isbn = {1755-3768}, pages = {424 -- 433}, year = {2008}, language = {en} } @article{SeidovaKotliarFoergeretal.2009, author = {Seidova, Seid-Fatima and Kotliar, Konstantin and Foerger, Frauke and Klopfer, Matthias and Lanzl, Ines}, title = {Functional retinal changes in Gaucher disease}, series = {Documenta Ophthalmologica}, volume = {118}, journal = {Documenta Ophthalmologica}, number = {2}, publisher = {Springer}, address = {Berlin}, isbn = {1573-2622}, pages = {151 -- 154}, year = {2009}, language = {en} } @article{DachwaldTuryshevDittusetal.2005, author = {Dachwald, Bernd and Turyshev, Slava G. and Dittus, H. and Shao, M. [u.a.]}, title = {Fundamental Physics with the Laser Astrometric Test Of Relativity / S.G. Turyshev ; H. Dittus ; M. Shao ... B.Dachwald ...}, series = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, journal = {Proceedings of the 39th ESLAB Symposium "Trends in Space Science and Cosmic Vision 2020" : 19 - 21 April 2005, ESTEC, Noordwijk, the Netherlands / European Space Agency. [Comp. by: F. Favata ...] . - (ESA SP ; 588)}, publisher = {ESA Publ. Div.}, address = {Noordwijk}, isbn = {9290928999}, pages = {8 -- 11}, year = {2005}, language = {en} } @article{RichterBraunsteinStaeudleetal.2021, author = {Richter, Charlotte and Braunstein, Bj{\"o}rn and St{\"a}udle, Benjamin and Attias, Julia and S{\"u}ss, Alexander and Weber, Tobias and Mileva, Katya N. and Rittweger, J{\"o}rn and Green, David A. and Albracht, Kirsten}, title = {Gastrocnemius medialis contractile behavior during running differs between simulated Lunar and Martian gravities}, series = {Scientific reports}, volume = {11}, journal = {Scientific reports}, number = {Article number: 22555}, publisher = {Springer Nature}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-021-00527-9}, pages = {13 Seiten}, year = {2021}, abstract = {The international partnership of space agencies has agreed to proceed forward to the Moon sustainably. Activities on the Lunar surface (0.16 g) will allow crewmembers to advance the exploration skills needed when expanding human presence to Mars (0.38 g). Whilst data from actual hypogravity activities are limited to the Apollo missions, simulation studies have indicated that ground reaction forces, mechanical work, muscle activation, and joint angles decrease with declining gravity level. However, these alterations in locomotion biomechanics do not necessarily scale to the gravity level, the reduction in gastrocnemius medialis activation even appears to level off around 0.2 g, while muscle activation pattern remains similar. Thus, it is difficult to predict whether gastrocnemius medialis contractile behavior during running on Moon will basically be the same as on Mars. Therefore, this study investigated lower limb joint kinematics and gastrocnemius medialis behavior during running at 1 g, simulated Martian gravity, and simulated Lunar gravity on the vertical treadmill facility. The results indicate that hypogravity-induced alterations in joint kinematics and contractile behavior still persist between simulated running on the Moon and Mars. This contrasts with the concept of a ceiling effect and should be carefully considered when evaluating exercise prescriptions and the transferability of locomotion practiced in Lunar gravity to Martian gravity.}, language = {en} } @article{RichterBraunsteinStaeudleetal.2021, author = {Richter, Charlotte and Braunstein, Bjoern and St{\"a}udle, Benjamin and Attias, Julia and Suess, Alexander and Weber, Tobias and Mileva, Katja N. and Rittweger, Joern and Green, David A. and Albracht, Kirsten}, title = {Gastrocnemius medialis contractile behavior is preserved during 30\% body weight supported gait training}, series = {Frontiers in Sports and Active Living}, volume = {2021}, journal = {Frontiers in Sports and Active Living}, number = {2}, publisher = {Frontiers}, address = {Lausanne}, issn = {2624-9367}, doi = {10.3389/fspor.2020.614559}, pages = {Artikel 614559}, year = {2021}, abstract = {Rehabilitative body weight supported gait training aims at restoring walking function as a key element in activities of daily living. Studies demonstrated reductions in muscle and joint forces, while kinematic gait patterns appear to be preserved with up to 30\% weight support. However, the influence of body weight support on muscle architecture, with respect to fascicle and series elastic element behavior is unknown, despite this having potential clinical implications for gait retraining. Eight males (31.9 ± 4.7 years) walked at 75\% of the speed at which they typically transition to running, with 0\% and 30\% body weight support on a lower-body positive pressure treadmill. Gastrocnemius medialis fascicle lengths and pennation angles were measured via ultrasonography. Additionally, joint kinematics were analyzed to determine gastrocnemius medialis muscle-tendon unit lengths, consisting of the muscle's contractile and series elastic elements. Series elastic element length was assessed using a muscle-tendon unit model. Depending on whether data were normally distributed, a paired t-test or Wilcoxon signed rank test was performed to determine if body weight supported walking had any effects on joint kinematics and fascicle-series elastic element behavior. Walking with 30\% body weight support had no statistically significant effect on joint kinematics and peak series elastic element length. Furthermore, at the time when peak series elastic element length was achieved, and on average across the entire stance phase, muscle-tendon unit length, fascicle length, pennation angle, and fascicle velocity were unchanged with respect to body weight support. In accordance with unchanged gait kinematics, preservation of fascicle-series elastic element behavior was observed during walking with 30\% body weight support, which suggests transferability of gait patterns to subsequent unsupported walking.}, language = {en} } @article{DemirciKurulganDemirciTrzewiketal.2009, author = {Demirci, Taylan and Kurulgan Demirci, Eylem and Trzewik, J{\"u}rgen and Linder, Peter and Digel, Ilya and Artmann, Gerhard and Sakizli, Meral and Temiz Artmann, Ayseg{\"u}l}, title = {Gene expression profile analysis of 3T3/NIH fibroblasts after one hour mechanical stress}, series = {IUBMB Life. 61 (2009), H. 3}, journal = {IUBMB Life. 61 (2009), H. 3}, publisher = {Wiley-VCH}, address = {Weinheim}, isbn = {1521-6543}, pages = {311 -- 312}, year = {2009}, language = {en} } @article{KurulganDemirciDemirciTrzewiketal.2011, author = {Kurulgan Demirci, Eylem and Demirci, T. and Trzewik, J{\"u}rgen and Linder, Peter and Karakulah, G. and Artmann, Gerhard and Sakizli, M. and Temiz Artmann, Ayseg{\"u}l}, title = {Genome-Wide Gene Expression Analysis of NIH 3T3 Cell Line Under Mechanical Stimulation}, series = {Cellular and molecular bioengineering. 4 (2011), H. 1}, journal = {Cellular and molecular bioengineering. 4 (2011), H. 1}, publisher = {Springer}, address = {Berlin}, isbn = {1865-5025}, pages = {46 -- 55}, year = {2011}, language = {en} } @article{ArtmannSchikarsky1993, author = {Artmann, Gerhard and Schikarsky, C.}, title = {Ginkgo Biloba extract (EGb 761) protects red blood cells from oxidative damage. Artmann, Gerhard Michael; Schikarsky, C.}, series = {Clinical Hemorheology. 13 (1993), H. 4}, journal = {Clinical Hemorheology. 13 (1993), H. 4}, isbn = {0271-5198}, pages = {529 -- 539}, year = {1993}, language = {en} } @article{LaackLeversStaat2013, author = {Laack, Walter van and Levers, A. and Staat, Manfred}, title = {Gonarthrosetherapie auf Kernspinresonanzbasis mit MBST-Vierjahresbeobachtungen}, series = {Orthop{\"a}dische Nachrichten : Zeitung f{\"u}r Orthop{\"a}die und Unfallchirurgie. 2013, H. 7/8}, journal = {Orthop{\"a}dische Nachrichten : Zeitung f{\"u}r Orthop{\"a}die und Unfallchirurgie. 2013, H. 7/8}, publisher = {Biermann}, address = {K{\"o}ln}, issn = {1437-2193}, pages = {13}, year = {2013}, language = {de} } @article{DachwaldMacDonaldMcInnes2007, author = {Dachwald, Bernd and MacDonald, Malcolm and McInnes, Colin R.}, title = {Heliocentric Solar Sail Orbit Transfers with Locally Optimal Control Laws / Malcolm Macdonald ; Colin McInnes ; Bernd Dachwald}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 1}, isbn = {0022-4650}, pages = {273 -- 276}, year = {2007}, language = {en} } @article{LeipoldFichtnerHeberetal.2006, author = {Leipold, M. and Fichtner, H. and Heber, B. and Groepper, P. and Lascar, S. and Burger, F. and Eiden, M. and Niederstadt, T. and Sickinger, C. and Herbeck, L. and Dachwald, Bernd and Seboldt, W.}, title = {Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System}, series = {Acta Astronautica. 59 (2006), H. 8-11}, journal = {Acta Astronautica. 59 (2006), H. 8-11}, isbn = {0094-5765}, pages = {786 -- 796}, year = {2006}, language = {en} } @article{DachwaldLeipoldFichtner2003, author = {Dachwald, Bernd and Leipold, M. and Fichtner, H.}, title = {Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System / M. Leipold ; H. Fichtner ; B. Heber ... B. Dachwald ...}, series = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, journal = {Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]}, publisher = {ESA}, address = {Noordwijk}, isbn = {92-9092-853-0}, pages = {367 -- 375}, year = {2003}, language = {en} } @article{ProbstBehbahaniBorrmannetal.2010, author = {Probst, M. and Behbahani, Mehdi and Borrmann, E. and Elgeti, S. and Nicolai, M. and Behr, M.}, title = {Hemodynamic Modeling for Numerical Analysis and Design of Medical Devices}, year = {2010}, language = {en} } @article{StadlerDigelArtmannetal.2008, author = {Stadler, A. M. and Digel, Ilya and Artmann, Gerhard and Embs, Jan P. and Zaccai, Joe and B{\"u}ldt, Georg}, title = {Hemoglobin Dynamics in Red Blood Cells: Correlation to Body Temperature}, series = {Biophysical Journal. 95 (2008), H. 11}, journal = {Biophysical Journal. 95 (2008), H. 11}, isbn = {1542-0086}, pages = {5449 -- 5461}, year = {2008}, language = {en} } @article{ArtmannZerlinDigel2008, author = {Artmann, Gerhard and Zerlin, Kay and Digel, Ilya}, title = {Hemoglobin Senses Body Temperature}, series = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, journal = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-75408-4}, pages = {415 -- 447}, year = {2008}, language = {en} } @article{ArtmannDigelZerlinetal.2009, author = {Artmann, Gerhard and Digel, Ilya and Zerlin, Kay and Maggakis-Kelemen, Christina and Linder, Peter and Porst, Dariusz and Kayser, Peter and Stadler, David and Dikta, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {Hemoglobin senses body temperature}, series = {European Biophysics Journal}, volume = {38}, journal = {European Biophysics Journal}, number = {5}, isbn = {0175-7571}, pages = {589 -- 600}, year = {2009}, language = {en} } @article{LiShiLandsmannetal.1998, author = {Li, Anlan and Shi, Young de and Landsmann, B. and Schankowski-Bouvier, P. and Dikta, Gerhard and Bauer, U. and Artmann, Gerhard}, title = {Hemorheology and walking distance of Peripheral Arterial Occlusive Disease patients during treatment with Ginkgo-biloba extract}, series = {Acta Pharmacologica Sinica = ZHONGUO YAOLI XUEBAO. 19 (1998), H. 5}, journal = {Acta Pharmacologica Sinica = ZHONGUO YAOLI XUEBAO. 19 (1998), H. 5}, isbn = {1745-7254}, pages = {417 -- 421}, year = {1998}, language = {en} } @article{LinderDigelTemizArtmannetal.2007, author = {Linder, Peter and Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Kayser, Peter and Porst, Dariusz and Artmann, Gerhard}, title = {High-throughput testing of mechanical forces generated in thin cell and tissue layers}, series = {Tissue Engineering. 13 (2007), H. 7}, journal = {Tissue Engineering. 13 (2007), H. 7}, isbn = {1076-3279}, pages = {1778 -- 1778}, year = {2007}, language = {en} } @article{SponagelSpaltofskiSteinhilper1988, author = {Sponagel, Stefan and Spaltofski, R. and Steinhilper, W.}, title = {Hochmolekulare Additive f{\"u}r die Gleitlagerschmierung. Spaltofski, R.; Sponagel, S.; Steinhilper, W.}, series = {Tribologie und Schmierungstechnik. 35 (1988), H. 5}, journal = {Tribologie und Schmierungstechnik. 35 (1988), H. 5}, isbn = {0036-6218}, pages = {236 -- 241}, year = {1988}, language = {de} } @article{SponagelSpaltofski1987, author = {Sponagel, Stefan and Spaltofski, R.}, title = {Hochmolekulare Zus{\"a}tze verbessern die Leichtlaufeigenschaft und die Tragf{\"a}higkeit von Schmierfilmen / Sponagel, S. ; Spaltofski, R.}, series = {Mineral{\"o}ltechnik. 32 (1987), H. 3}, journal = {Mineral{\"o}ltechnik. 32 (1987), H. 3}, isbn = {0341-1893}, pages = {28 S.}, year = {1987}, language = {de} } @article{BaroudWuBohneretal.2003, author = {Baroud, G. and Wu, J.Z. and Bohner, M and Sponagel, Stefan and Steffen, T.}, title = {How to determine the permeability for cement infiltration into osteoporotic cancellous bone}, series = {Medical Engineering \& Physics. 25 (2003), H. 4}, journal = {Medical Engineering \& Physics. 25 (2003), H. 4}, issn = {1350-4533}, pages = {283 -- 288}, year = {2003}, abstract = {Cement augmentation is an emerging surgical procedure in which bone cement is used to infiltrate and reinforce osteoporotic vertebrae. Although this infiltration procedure has been widely applied, it is performed empirically and little is known about the flow characteristics of cement during the injection process. We present a theoretical and experimental approach to investigate the intertrabecular bone permeability during the infiltration procedure. The cement permeability was considered to be dependent on time, bone porosity, and cement viscosity in our analysis. In order to determine the time-dependent permeability, ten cancellous bone cores were harvested from osteoporotic vertebrae, infiltrated with acrylic cement at a constant flow rate, and the pressure drop across the cores during the infiltration was measured. The viscosity dependence of the permeability was determined based on published experimental data. The theoretical model for the permeability as a function of bone porosity and time was then fit to the testing data. Our findings suggest that the intertrabecular bone permeability depends strongly on time. For instance, the initial permeability (60.89 mm4/N.s) reduced to approximately 63\% of its original value within 18 seconds. This study is the first to analyze cement flow through osteoporotic bone. The theoretical and experimental models provided in this paper are generic. Thus, they can be used to systematically study and optimize the infiltration process for clinical practice.}, subject = {Osteoporose}, language = {en} } @article{ArtmannGorbatenkovaPanasenko2000, author = {Artmann, Gerhard and Gorbatenkova, E. A. and Panasenko, O. M.}, title = {Hypochlorous acid and human blood low density lipoproteins modified by hypochlorous acid increase erythrocyte adhesion to endothelial cells. Gorbatenkova, E. A.; Artmann, Gerhard Michael; Panasenko, O. M.}, series = {Membrane and cell biology. 13 (2000), H. 4}, journal = {Membrane and cell biology. 13 (2000), H. 4}, isbn = {1023-6597}, pages = {537 -- 546}, year = {2000}, language = {en} } @article{DoorschodtSchreinemachersBehbahanietal.2011, author = {Doorschodt, B. M. and Schreinemachers, M. C. J. M. and Behbahani, Mehdi and Florquin, S. and Weis, J. and Staat, Manfred and Tolba, R. H.}, title = {Hypothermic machine perfusion of kidney grafts: which pressure is preferred}, series = {Annals of Biomedical Engineering. 39 (2011), H. 3}, journal = {Annals of Biomedical Engineering. 39 (2011), H. 3}, publisher = {Springer}, address = {Berlin}, isbn = {1573-9686}, pages = {1051 -- 1059}, year = {2011}, language = {en} } @article{SponagelUngerSpies2003, author = {Sponagel, Stefan and Unger, J. and Spies, K. H.}, title = {H{\"a}rtebegriff im Zusammenhang mit Vernetzung, Bruchdehnung und Dauerfestigkeit eines Elastomers}, series = {Kautschuk Gummi Kunststoffe. 56 (2003), H. 11}, journal = {Kautschuk Gummi Kunststoffe. 56 (2003), H. 11}, isbn = {0948-3276}, pages = {608 -- 613}, year = {2003}, language = {de} } @article{DachwaldMikuckiTulaczyketal.2014, author = {Dachwald, Bernd and Mikucki, Jill and Tulaczyk, Slawek and Digel, Ilya and Espe, Clemens and Feldmann, Marco and Francke, Gero and Kowalski, Julia and Xu, Changsheng}, title = {IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems}, series = {Annals of Glaciology}, volume = {55}, journal = {Annals of Glaciology}, number = {65}, publisher = {Cambridge University Press}, address = {Cambridge}, issn = {1727-5644}, doi = {10.3189/2014AoG65A004}, pages = {14 -- 22}, year = {2014}, abstract = {There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample.}, language = {en} } @article{WerfelGuenthnerHapfelmeieretal.2022, author = {Werfel, Stanislas and G{\"u}nthner, Roman and Hapfelmeier, Alexander and Hanssen, Henner and Kotliar, Konstantin and Heemann, Uwe and Schmaderer, Christoph}, title = {Identification of cardiovascular high-risk groups from dynamic retinal vessel signals using untargeted machine learning}, series = {Cardiovascular Research}, volume = {118}, journal = {Cardiovascular Research}, number = {2}, editor = {Guzik, Tomasz J.}, publisher = {Oxford University Press}, address = {Oxford}, issn = {0008-6363}, doi = {10.1093/cvr/cvab040}, pages = {612 -- 621}, year = {2022}, abstract = {Dynamic retinal vessel analysis (DVA) provides a non-invasive way to assess microvascular function in patients and potentially to improve predictions of individual cardiovascular (CV) risk. The aim of our study was to use untargeted machine learning on DVA in order to improve CV mortality prediction and identify corresponding response alterations.}, language = {en} } @article{BogoyavlenskiyBerezinOgnevaetal.1999, author = {Bogoyavlenskiy, A. P. and Berezin, V. E. and Ogneva, A. V. and Tolmacheva, V. P. and Digel, Ilya and Khudyakova, S. S.}, title = {Immunostimulating activity of a saponin-containing extract of Saponaria officinalis}, series = {Voprosy virusologii}, volume = {44}, journal = {Voprosy virusologii}, number = {5}, issn = {0507-4088}, pages = {229 -- 232}, year = {1999}, language = {en} } @article{DachwaldMcDonaldMcInnesetal.2007, author = {Dachwald, Bernd and McDonald, Malcolm and McInnes, Colin R. and Mengali, Giovanni}, title = {Impact of Optical Degradation on Solar Sail Mission Performance}, series = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, journal = {Journal of Spacecraft and Rockets. 44 (2007), H. 4}, isbn = {0022-4650}, pages = {740 -- 749}, year = {2007}, language = {en} } @article{TemizArtmannResmiAkhunlaretal.2005, author = {Temiz Artmann, Ayseg{\"u}l and Resmi, Halil and Akhunlar, H{\"u}lya and G{\"u}ner, G{\"u}l}, title = {In vitro effects of high glucose concentrations on membrane protein sulfhydryl oxidation, G-actin and deformability of human erythrocytes. Resmi, Halil ; Akhunlar, H{\"u}lya ; Temiz Artmann, Ayseg{\"u}l ; G{\"u}ner, G{\"u}l}, series = {Cell biochemistry and function. 23 (2005), H. 3}, journal = {Cell biochemistry and function. 23 (2005), H. 3}, isbn = {0263-6484}, pages = {163 -- 168}, year = {2005}, language = {en} } @article{TemizArtmannBaskurtEdremitlioglu1994, author = {Temiz Artmann, Ayseg{\"u}l and Baskurt, O. K. and Edremitlioglu, M.}, title = {In vitro effects of in vivo activated leukocytes on red blood cell filterability and lipid peroxidation. Baskurt, O.K.; Edremitlioglu, M.; Temiz, A.}, series = {Clinical Hemorheology. 14 (1994), H. 4}, journal = {Clinical Hemorheology. 14 (1994), H. 4}, pages = {591 -- 596}, year = {1994}, language = {en} } @article{BrockhausBehbahaniMurisetal.2021, author = {Brockhaus, Moritz K. and Behbahani, Mehdi and Muris, Farina and Jansen, Sebastian V. and Schmitz- Rode, Thomas and Steinseifer, Ulrich and Clauser, Johanna C.}, title = {In vitro thrombogenicity testing of pulsatile mechanical circulatory support systems: Design and proof-of-concept}, series = {Artificial Organs}, volume = {45}, journal = {Artificial Organs}, number = {12}, publisher = {Wiley}, address = {Weinheim}, issn = {1525-1594}, doi = {10.1111/aor.14046}, pages = {1513 -- 1521}, year = {2021}, abstract = {Thrombogenic complications are a main issue in mechanical circulatory support (MCS). There is no validated in vitro method available to quantitatively assess the thrombogenic performance of pulsatile MCS devices under realistic hemodynamic conditions. The aim of this study is to propose a method to evaluate the thrombogenic potential of new designs without the use of complex in-vivo trials. This study presents a novel in vitro method for reproducible thrombogenicity testing of pulsatile MCS systems using low molecular weight heparinized porcine blood. Blood parameters are continuously measured with full blood thromboelastometry (ROTEM; EXTEM, FIBTEM and a custom-made analysis HEPNATEM). Thrombus formation is optically observed after four hours of testing. The results of three experiments are presented each with two parallel loops. The area of thrombus formation inside the MCS device was reproducible. The implantation of a filter inside the loop catches embolizing thrombi without a measurable increase of platelet activation, allowing conclusions of the place of origin of thrombi inside the device. EXTEM and FIBTEM parameters such as clotting velocity (α) and maximum clot firmness (MCF) show a total decrease by around 6\% with a characteristic kink after 180 minutes. HEPNATEM α and MCF rise within the first 180 minutes indicate a continuously increasing activation level of coagulation. After 180 minutes, the consumption of clotting factors prevails, resulting in a decrease of α and MCF. With the designed mock loop and the presented protocol we are able to identify thrombogenic hot spots inside a pulsatile pump and characterize their thrombogenic potential.}, language = {en} } @article{Digel2010, author = {Digel, Ilya}, title = {In-situ biological decontamination of an ice melting probe}, year = {2010}, language = {en} } @article{HeinkeKnickerAlbracht2020, author = {Heinke, Lars N. and Knicker, Axel J. and Albracht, Kirsten}, title = {Increased shoulder muscle stretch reflex elicitability in supine subject posture}, series = {Isokinetics and Exercise Science}, volume = {28}, journal = {Isokinetics and Exercise Science}, number = {2}, publisher = {IOS Press}, address = {Amsterdam}, issn = {1878-5913}, doi = {10.3233/IES-192219}, pages = {139 -- 146}, year = {2020}, abstract = {BACKGROUND: Muscle stretch reflexes are widely used to examine neural muscle function. The knowledge of reflex response in muscles crossing the shoulder is limited. OBJECTIVE: To quantify reflex modulation according to various subject postures and different procedures of muscle pre-activation steering. METHODS: Thirteen healthy male participants performed two sets of external shoulder rotation stretches in various positions and with different procedures of muscle pre-activation steering on an isokinetic dynamometer over a range of two different pre-activation levels. All stretches were applied with a dynamometer acceleration of 104∘/s2 and a velocity of 150∘/s. Electromyographical response was measured via sEMG. RESULTS: Consistent reflexive response was observed in all tested muscles in all experimental conditions. The reflex elicitation rate revealed a significant muscle main effect (F (5,288) = 2.358, ρ= 0.040; η2= 0.039; f= 0.637) and a significant test condition main effect (F (1,288) = 5.884, ρ= 0.016; η2= 0.020; f= 0.143). Reflex latency revealed a significant muscle pre-activation level main effect (F (1,274) = 5.008, ρ= 0.026; η2= 0.018; f= 0.469). CONCLUSION: Muscular reflexive response was more consistent in the primary internal rotators of the shoulder. Supine posture in combination with visual feedback of muscle pre-activation level enhanced the reflex elicitation rate.}, language = {en} } @article{NguyenDuongTranetal.2012, author = {Nguyen, Nhu Huynh and Duong, Minh Tuan and Tran, Thanh Ngoc and Pham, Phu Tinh and Grottke, O. and Tolba, R. and Staat, Manfred}, title = {Influence of a freeze-thaw cycle on the stress-stretch curves of tissues of porcine abdominal organs}, series = {Journal of Biomechanics}, volume = {45}, journal = {Journal of Biomechanics}, number = {14}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380}, doi = {10.1016/j.jbiomech.2012.07.008}, pages = {2382 -- 2386}, year = {2012}, abstract = {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.}, language = {en} } @article{ArtmannSchmidSchoenbeinSchroederetal.1988, author = {Artmann, Gerhard and Schmid-Sch{\"o}nbein, H. and Schr{\"o}der, Susanne and Grebe, R. [u.a.]}, title = {Influence of Moxaverine-HCL on Membrane Curvature and Microsieve Filterability of Red Cells after Exposure to Hyperosmolarity and Lactacidosis. Schmid-Sch{\"o}nbein, H.; Schr{\"o}der, Susanne; Grebe, R.; Artmann, Gerhard Michael, Eschweiler, H; Teitel, P.}, series = {Arzneimittelforschung. 38 (1988), H. 5}, journal = {Arzneimittelforschung. 38 (1988), H. 5}, isbn = {0004-4172}, pages = {710 -- 716}, year = {1988}, language = {en} } @article{DuongNguyenTranetal.2015, author = {Duong, Minh Tuan and Nguyen, Nhu Huynh and Tran, Thanh Ngoc and Tolba, R. H. and Staat, Manfred}, title = {Influence of refrigerated storage on tensile mechanical properties of porcine liver and spleen}, series = {International biomechanics}, volume = {Vol. 2}, journal = {International biomechanics}, number = {Iss. 1}, publisher = {Taylor \& Francis}, address = {London}, issn = {2333-5432}, doi = {10.1080/23335432.2015.1049295}, pages = {79 -- 88}, year = {2015}, language = {en} } @article{LenzKahmannBehbahanietal.2022, author = {Lenz, Maximilian and Kahmann, Stephanie Lucina and Behbahani, Mehdi and Pennig, Lenhard and Hackl, Michael and Leschinger, Tim and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {Influence of rotator cuff preload on fracture configuration in proximal humerus fractures: a proof of concept for fracture simulation}, series = {Archives of Orthopaedic and Trauma Surgery}, journal = {Archives of Orthopaedic and Trauma Surgery}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1434-3916}, doi = {10.1007/s00402-022-04471-9}, year = {2022}, abstract = {Introduction In regard of surgical training, the reproducible simulation of life-like proximal humerus fractures in human cadaveric specimens is desirable. The aim of the present study was to develop a technique that allows simulation of realistic proximal humerus fractures and to analyse the influence of rotator cuff preload on the generated lesions in regards of fracture configuration. Materials and methods Ten cadaveric specimens (6 left, 4 right) were fractured using a custom-made drop-test bench, in two groups. Five specimens were fractured without rotator cuff preload, while the other five were fractured with the tendons of the rotator cuff preloaded with 2 kg each. The humeral shaft and the shortened scapula were potted. The humerus was positioned at 90° of abduction and 10° of internal rotation to simulate a fall on the elevated arm. In two specimens of each group, the emergence of the fractures was documented with high-speed video imaging. Pre-fracture radiographs were taken to evaluate the deltoid-tuberosity index as a measure of bone density. Post-fracture X-rays and CT scans were performed to define the exact fracture configurations. Neer's classification was used to analyse the fractures. Results In all ten cadaveric specimens life-like proximal humerus fractures were achieved. Two III-part and three IV-part fractures resulted in each group. The preloading of the rotator cuff muscles had no further influence on the fracture configuration. High-speed videos of the fracture simulation revealed identical fracture mechanisms for both groups. We observed a two-step fracture mechanism, with initial impaction of the head segment against the glenoid followed by fracturing of the head and the tuberosities and then with further impaction of the shaft against the acromion, which lead to separation of the tuberosities. Conclusion A high energetic axial impulse can reliably induce realistic proximal humerus fractures in cadaveric specimens. The preload of the rotator cuff muscles had no influence on initial fracture configuration. Therefore, fracture simulation in the proximal humerus is less elaborate. Using the presented technique, pre-fractured specimens are available for real-life surgical education.}, language = {en} } @article{KoppSchunckGosauetal.2020, author = {Kopp, Alexander and Schunck, Laura and Gosau, Martin and Smeets, Ralf and Burg, Simon and Fuest, Sandra and Kr{\"o}ger, Nadja and Zinser, Max and Krohn, Sebastian and Behbahani, Mehdi and K{\"o}pf, Marius and Lauts, Lisa and Rutkowski, Rico}, title = {Influence of the casting concentration on the mechanical and optical properties of Fa/CaCl2-derived silk fibroin membranes}, series = {International Journal of Molecular Sciences}, volume = {21}, journal = {International Journal of Molecular Sciences}, number = {18 art. no. 6704}, publisher = {MDPI}, address = {Basel}, issn = {1422-0067}, doi = {10.3390/ijms21186704}, year = {2020}, abstract = {In this study, we describe the manufacturing and characterization of silk fibroin membranes derived from the silkworm Bombyx mori. To date, the dissolution process used in this study has only been researched to a limited extent, although it entails various potential advantages, such as reduced expenses and the absence of toxic chemicals in comparison to other conventional techniques. Therefore, the aim of this study was to determine the influence of different fibroin concentrations on the process output and resulting membrane properties. Casted membranes were thus characterized with regard to their mechanical, structural and optical assets via tensile testing, SEM, light microscopy and spectrophotometry. Cytotoxicity was evaluated using BrdU, XTT, and LDH assays, followed by live-dead staining. The formic acid (FA) dissolution method was proven to be suitable for the manufacturing of transparent and mechanically stable membranes. The fibroin concentration affects both thickness and transparency of the membranes. The membranes did not exhibit any signs of cytotoxicity. When compared to other current scientific and technical benchmarks, the manufactured membranes displayed promising potential for various biomedical applications. Further research is nevertheless necessary to improve reproducible manufacturing, including a more uniform thickness, less impurity and physiological pH within the membranes.}, language = {en} } @article{AlbrachtArampatzis2006, author = {Albracht, Kirsten and Arampatzis, Adamantios}, title = {Influence of the mechanical properties of the muscle-tendon unit on force generation in runners with different running economy}, series = {Biological Cybernetics}, volume = {95}, journal = {Biological Cybernetics}, number = {1}, issn = {1432-0770}, doi = {10.1007/s00422-006-0070-z}, pages = {87 -- 96}, year = {2006}, language = {en} } @article{ArtmannZhouStacheBuettneretal.2002, author = {Artmann, Gerhard and Zhou-Stache, J. and Buettner, R. and Mittermayer, C. [u.a.]}, title = {Inhibition of TNF-alpha induced cell death in HUVEC and Jurkat cells by protocatechuic acid. Zhou-Stache, J.; Buettner, R.; Artmann, Gerhard Michael; Mittermayer, C.; Bosserhoff, A. K.}, series = {Medical and Biological Engineering and Computing. 40 (2002), H. 6}, journal = {Medical and Biological Engineering and Computing. 40 (2002), H. 6}, isbn = {0140-0118}, pages = {698 -- 703}, year = {2002}, language = {en} }