@article{MaggakisKelemenBiselliArtmann2002, author = {Maggakis-Kelemen, Christina and Biselli, Manfred and Artmann, Gerhard}, title = {Determination of the elastic shear modulus of cultured human red blood cells}, series = {Biomedizinische Technik. 47 (2002), H. Suppl. 1 Pt. 1}, journal = {Biomedizinische Technik. 47 (2002), H. Suppl. 1 Pt. 1}, isbn = {0013-5585}, pages = {106 -- 109}, year = {2002}, language = {en} } @article{MaggakisKelemenBorkKayseretal.2003, author = {Maggakis-Kelemen, C. and Bork, M. and Kayser, Peter and Biselli, Manfred and Artmann, Gerhard}, title = {Biological and mechanical quality of red blood cells cultured from human umbilical cord blood stem cells}, series = {Medical and biological engineering and computing. 41 (2003), H. 3}, journal = {Medical and biological engineering and computing. 41 (2003), H. 3}, isbn = {0140-0118}, pages = {350 -- 356}, year = {2003}, language = {en} } @incollection{MacdonaldMcGrathAppourchauxetal.2014, author = {Macdonald, Malcolm and McGrath, C. and Appourchaux, T. and Dachwald, Bernd and Finsterle, W. and Gizon, L. and Liewer, P. C. and McInnes, Colin R. and Mengali, G. and Seboldt, W. and Sekii, T. and Solanki, S. K. and Velli, M. and Wimmer-Schweingruber, R. F. and Spietz, Peter and Reinhard, Ruedeger}, title = {Gossamer roadmap technology reference study for a solar polar mission}, series = {Advances in solar sailing}, booktitle = {Advances in solar sailing}, editor = {Macdonald, Malcolm}, publisher = {Springer}, address = {Berlin, Heidelberg}, isbn = {978-3-642-34906-5}, doi = {10.1007/978-3-642-34907-2_17}, pages = {243 -- 257}, year = {2014}, abstract = {A technology reference study for a solar polar mission is presented. The study uses novel analytical methods to quantify the mission design space including the required sail performance to achieve a given solar polar observation angle within a given timeframe and thus to derive mass allocations for the remaining spacecraft sub-systems, that is excluding the solar sail sub-system. A parametric, bottom-up, system mass budget analysis is then used to establish the required sail technology to deliver a range of science payloads, and to establish where such payloads can be delivered to within a given timeframe. It is found that a solar polar mission requires a solar sail of side-length 100-125 m to deliver a 'sufficient value' minimum science payload, and that a 2.5 μm sail film substrate is typically required, however the design is much less sensitive to the boom specific mass.}, language = {en} } @article{LyonsMikuckiGermanetal.2019, author = {Lyons, W. Berry and Mikucki, Jill A. and German, Laura A. and Welch, Kathleen A. and Welch, Susan A. and Gardener, Christopher B. and Tulaczyk, Slawek M. and Pettit, Erin C. and Kowalski, Julia and Dachwald, Bernd}, title = {The Geochemistry of Englacial Brine from Taylor Glacier, Antarctica}, series = {Journal of Geophysical Research: Biogeosciences}, journal = {Journal of Geophysical Research: Biogeosciences}, publisher = {Wiley}, address = {Hoboken}, issn = {2169-8961}, doi = {10.1029/2018JG004411}, year = {2019}, language = {en} } @inproceedings{LoebSchartnerDachwaldetal.2007, author = {Loeb, Horst Wolfgang and Schartner, Karl-Heinz and Dachwald, Bernd and Seboldt, Wolfgang}, title = {SEP-Sample return from a main belt asteroid}, series = {30th International Electric Propulsion Conference}, booktitle = {30th International Electric Propulsion Conference}, pages = {1 -- 11}, year = {2007}, abstract = {By DLR-contact, sample return missions to the large main-belt asteroid "19, Fortuna" have been studied. The mission scenario has been based on three ion thrusters of the RIT-22 model, which is presently under space qualification, and on solar arrays equipped with triple-junction GaAs solar cells. After having designed the spacecraft, the orbit-to-orbit trajectories for both, a one-way SEP mission with a chemical sample return and an all-SEP return mission, have been optimized using a combination of artificial neural networks with evolutionary algorithms. Additionally, body-to-body trajectories have been investigated within a launch period between 2012 and 2015. For orbit-to-orbit calculation, the launch masses of the hybrid mission and of the all-SEP mission resulted in 2.05 tons and 1.56 tons, respectively, including a scientific payload of 246 kg. For the related transfer durations 4.14 yrs and 4.62 yrs were obtained. Finally, a comparison between the mission scenarios based on SEP and on NEP have been carried out favouring clearly SEP.}, language = {en} } @article{LoebSchartnerDachwaldetal.2012, author = {Loeb, Horst Wolfgang and Schartner, Karl-Heinz and Dachwald, Bernd and Ohndorf, Andreas and Seboldt, Wolfgang}, title = {Interstellar heliopause probe}, series = {Труды МАИ}, journal = {Труды МАИ}, number = {60}, publisher = {Moskauer Staatliches Luftfahrtinstitut (МАИ)}, address = {Moskau}, pages = {2 -- 2}, year = {2012}, abstract = {There is common agreement within the scientific community that in order to understand our local galactic environment it will be necessary to send a spacecraft into the region beyond the solar wind termination shock. Considering distances of 200 AU for a new mission, one needs a spacecraft traveling at a speed of close to 10 AU/yr in order to keep the mission duration in the range of less than 25 yrs, a transfer time postulated by European Space Agency (ESA). Two propulsion options for the mission have been proposed and discussed so far: the solar sail propulsion and the ballistic/radioisotope-electric propulsion (REP). As a further alternative, we here investigate a combination of solar-electric propulsion (SEP) and REP. The SEP stage consists of six 22-cms diameter RIT-22 ion thrusters working with a high specific impulse of 7377 s corresponding to a positive grid voltage of 5 kV. Solar power of 53 kW at begin of mission (BOM) is provided by a lightweight solar array.}, language = {en} } @inproceedings{LoebSchartnerSeboldtetal.2006, author = {Loeb, Horst W. and Schartner, Karl-Heinz and Seboldt, Wolfgang and Dachwald, Bernd and Streppel, Joern and Meusemann, Hans and Sch{\"u}lke, Peter}, title = {SEP for a lander mission to the jovian moon europa}, series = {57th International Astronautical Congress}, booktitle = {57th International Astronautical Congress}, doi = {10.2514/6.IAC-06-C4.4.04}, pages = {1 -- 12}, year = {2006}, abstract = {Under DLR-contract, Giessen University and DLR Cologne are studying solar-electric propulsion missions (SEP) to the outer regions of the solar system. The most challenging reference mission concerns the transport of a 1.35-tons chemical lander spacecraft into an 80-RJ circular orbit around Jupiter, which would enable to place a 375 kg lander with 50 kg of scientific instruments on the surface of the icy moon "Europa". Thorough analyses show that the best solution in terms of SEP launch mass times thrusting time would be a two-stage EP module and a triple-junction solar array with concentrators which would be deployed step by step. Mission performance optimizations suggest to propel the spacecraft in the first EP stage by 6 gridded ion thrusters, running at 4.0 kV of beam voltage, which would save launch mass, and in the second stage by 4 thrusters with 1.25 to 1.5 kV of positive high voltage saving thrusting time. In this way, the launch mass of the spacecraft would be kept within 5.3 tons. Without a launcher's C3 and interplanetary gravity assists, Jupiter might be reached within about 4 yrs. The spiraling-down into the parking orbit would need another 1.8 yrs. This "large mission" can be scaled down to a smaller one, e.g., by halving all masses, the solar array power, and the number of thrusters. Due to their reliability, long lifetime and easy control, RIT-22 engines have been chosen for mission analysis. Based on precise tests, the thruster performance has been modeled.}, language = {en} } @inproceedings{LoebSchartnerDachwaldetal.2011, author = {Loeb, Horst W. and Schartner, Karl-Heinz and Dachwald, Bernd and Ohndorf, Andreas and Seboldt, Wolfgang}, title = {An Interstellar - Heliopause mission using a combination of solar/radioisotope electric propulsion}, series = {Presented at the 32nd International Electric Propulsion Conference}, booktitle = {Presented at the 32nd International Electric Propulsion Conference}, pages = {1 -- 7}, year = {2011}, abstract = {There is common agreement within the scientific community that in order to understand our local galactic environment it will be necessary to send a spacecraft into the region beyond the solar wind termination shock. Considering distances of 200 AU for a new mission, one needs a spacecraft travelling at a speed of close to 10 AU/yr in order to keep the mission duration in the range of less than 25 yrs, a transfer time postulated by ESA.Two propulsion options for the mission have been proposed and discussed so far: the solar sail propulsion and the ballistic/radioisotope electric propulsion. As a further alternative, we here investigate a combination of solar-electric propulsion and radioisotope-electric propulsion. The solar-electric propulsion stage consists of six 22 cm diameter "RIT-22"ion thrusters working with a high specific impulse of 7377 s corresponding to a positive grid voltage of 5 kV. Solar power of 53 kW BOM is provided by a light-weight solar array. The REP-stage consists of four space-proven 10 cm diameter "RIT-10" ion thrusters that will be operating one after the other for 9 yrs in total. Four advanced radioisotope generators provide 648 W at BOM. The scientific instrument package is oriented at earlier studies. For its mass and electric power requirement 35 kg and 35 W are assessed, respectively. Optimized trajectory calculations, treated in a separate contribution, are based on our "InTrance" method.The program yields a burn out of the REP stage in a distance of 79.6 AU for a usage of 154 kg of Xe propellant. With a C3 = 45,1 (km/s)2 a heliocentric probe velocity of 10 AU/yr is reached at this distance, provided a close Jupiter gravity assist adds a velocity increment of 2.7 AU/yr. A transfer time of 23.8 yrs results for this scenario requiring about 450 kg Xe for the SEP stage, jettisoned at 3 AU. We interpret the SEP/REP propulsion as a competing alternative to solar sail and ballistic/REP propulsion. Omiting a Jupiter fly-by even allows more launch flexibility, leaving the mission duration in the range of the ESA specification.}, language = {en} } @article{LiphardtFernandezGonzaloAlbrachtetal.2023, author = {Liphardt, Anna-Maria and Fernandez-Gonzalo, Rodrigo and Albracht, Kirsten and Rittweger, J{\"o}rn and Vico, Laurence}, title = {Musculoskeletal research in human space flight - unmet needs for the success of crewed deep space exploration}, series = {npj Microgravity}, volume = {9}, journal = {npj Microgravity}, number = {Article number: 9}, publisher = {Springer Nature}, issn = {2373-8065}, doi = {10.1038/s41526-023-00258-3}, pages = {1 -- 9}, year = {2023}, abstract = {Based on the European Space Agency (ESA) Science in Space Environment (SciSpacE) community White Paper "Human Physiology - Musculoskeletal system", this perspective highlights unmet needs and suggests new avenues for future studies in musculoskeletal research to enable crewed exploration missions. The musculoskeletal system is essential for sustaining physical function and energy metabolism, and the maintenance of health during exploration missions, and consequently mission success, will be tightly linked to musculoskeletal function. Data collection from current space missions from pre-, during-, and post-flight periods would provide important information to understand and ultimately offset musculoskeletal alterations during long-term spaceflight. In addition, understanding the kinetics of the different components of the musculoskeletal system in parallel with a detailed description of the molecular mechanisms driving these alterations appears to be the best approach to address potential musculoskeletal problems that future exploratory-mission crew will face. These research efforts should be accompanied by technical advances in molecular and phenotypic monitoring tools to provide in-flight real-time feedback.}, 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{LinderBecklerDoerretal.2019, author = {Linder, Peter and Beckler, Matthias and Doerr, Leo and Stoelzle-Feix, Sonja and Fertig, Niels and Jung, Alexander and Staat, Manfred and Gossmann, Matthias}, title = {A new in vitro tool to investigate cardiac contractility under physiological mechanical conditions}, series = {Journal of Pharmacological and Toxicological Methods}, volume = {99}, journal = {Journal of Pharmacological and Toxicological Methods}, number = {Article number 106595}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1056-8719}, doi = {10.1016/j.vascn.2019.05.162}, year = {2019}, language = {en} } @article{LindenFischoederLaacketal.2013, author = {Linden, A. and Fisch{\"o}der, M. and Laack, Walter van and Staat, Manfred}, title = {Einschr{\"a}nkung von Taluskippung und -vorschub durch Sprunggelenkorthesen nach fibularer Bandruptur}, series = {OUP Zeitschrift f{\"u}r die orthop{\"a}dische und unfallchirurgische Praxis}, volume = {2}, journal = {OUP Zeitschrift f{\"u}r die orthop{\"a}dische und unfallchirurgische Praxis}, number = {6}, publisher = {Deutscher {\"A}rzte-Verl.}, address = {K{\"o}ln}, isbn = {2193-5785}, doi = {10.3238/oup.2013.0306-0309}, pages = {306 -- 309}, year = {2013}, abstract = {Die fibulare Bandruptur z{\"a}hlt zu einer der am h{\"a}ufigsten auftretenden Verletzungen des Bewegungsapparats. In den meisten F{\"a}llen wird heute die konservativ fr{\"u}hfunktionelle Therapie mit Sprunggelenkorthesen allgemein bevorzugt. Im Rahmen der vorliegenden Studie wurden 14 verschiedene Sprunggelenkorthesen im Hinblick auf ihre Einschr{\"a}nkung 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" R{\"o}ntgenaufnahmen 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.}, language = {de} } @article{LeversStaatLaack2016, author = {Levers, A. and Staat, Manfred and Laack, Walter van}, title = {Analysis of the long-term effect of the MBST® nuclear magnetic resonance therapy on gonarthrosis}, series = {Orthopedic Practice}, volume = {47}, journal = {Orthopedic Practice}, number = {11}, pages = {521 -- 528}, year = {2016}, language = {en} } @article{LeschingerBirgelHackletal.2019, author = {Leschinger, Tim and Birgel, Stefan and Hackl, Michael and Staat, Manfred and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {A musculoskeletal shoulder simulation of moment arms and joint reaction forces after medialization of the supraspinatus footprint in rotator cuff repair}, series = {Computer Methods in Biomechanics and Biomedical Engineering}, journal = {Computer Methods in Biomechanics and Biomedical Engineering}, number = {Early view}, publisher = {Taylor \& Francis}, address = {London}, doi = {10.1080/10255842.2019.1572749}, year = {2019}, language = {en} } @article{LeschingerBeschAydinetal.2019, author = {Leschinger, Tim and Besch, Katharina and Aydin, Cansu and Staat, Manfred and Scaal, Martin and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {Irreparable rotator cuff tears: a biomechanical comparison of superior capsuloligamentous complex reconstruction techniques and an interposition graft technique}, series = {The Orthopaedic Journal of Sports Medicine}, volume = {7}, journal = {The Orthopaedic Journal of Sports Medicine}, number = {8}, doi = {10.1177/2325967119864590}, pages = {1 -- 5}, year = {2019}, 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{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{LeimenaArtmannDachwaldetal.2010, author = {Leimena, W. and Artmann, Gerhard and Dachwald, Bernd and Temiz Artmann, Ayseg{\"u}l and Gossmann, Matthias and Digel, Ilya}, title = {Feasibility of an in-situ microbial decontamination of an ice-melting probe}, series = {Eurasian Chemico-Technological Journal. 12 (2010), H. 2}, journal = {Eurasian Chemico-Technological Journal. 12 (2010), H. 2}, isbn = {1562-3920}, pages = {145 -- 150}, year = {2010}, language = {en} } @article{LapitanRogatkinPersheyevetal.2018, author = {Lapitan, Denis G. and Rogatkin, Dmitrii A. and Persheyev, Sydulla K. and Kotliar, Konstantin}, title = {False spectra formation in the differential two-channel scheme of the laser Doppler flowmeter}, series = {Biomedizinische Technik}, volume = {63}, journal = {Biomedizinische Technik}, number = {4}, publisher = {De Gruyter}, address = {Berlin}, issn = {0013-5585}, doi = {10.1515/bmt-2017-0060}, pages = {439 -- 444}, year = {2018}, abstract = {Noise in the differential two-channel scheme of a classic laser Doppler flowmetry (LDF) instrument was studied. Formation of false spectral components in the output signal due to beating of electrical signals in the differential amplifier was found out. The improved block-diagram of the flowmeter was developed allowing to reduce the noise.}, language = {en} } @article{LanzlSeidovaMaieretal.2011, author = {Lanzl, Ines M. and Seidova, Seid-Fatima and Maier, Mathias and Schmidt-Trucks{\"a}ss, Arno and Halle, Martin and Kotliar, Konstantin}, title = {Dynamic retinal vessel response to flicker in age-related macular degeneration patients before and after vascular endothelial growth factor inhibitor injection}, series = {Acta Ophthalmologica}, volume = {89}, journal = {Acta Ophthalmologica}, number = {5}, publisher = {Wiley}, address = {Weinheim}, isbn = {1755-3768}, pages = {472 -- 479}, year = {2011}, language = {en} } @article{LanzlSeidovaErbenetal.2010, author = {Lanzl, Ines M. and Seidova, Seid-Fatima and Erben, A. and Th{\"u}rmel, K. and Kotliar, Konstantin}, title = {Diffuse stromale Hornhauttr{\"u}bungen und Ver{\"a}nderungen der H{\"a}nde}, series = {Der Ophthalmologe}, volume = {107}, journal = {Der Ophthalmologe}, number = {4}, publisher = {Springer}, address = {Berlin}, issn = {1433-0423}, doi = {10.1007/s00347-009-2066-2}, pages = {363 -- 365}, year = {2010}, abstract = {Bilaterale stromale Hornhauttr{\"u}bungen sind f{\"u}r den Augenarzt eine differenzialdiagnostische Herausforderung. Im folgenden Beitrag werden 2 Patieninnen (30 und 36 Jahre) mit unterschiedlich stark ausgepr{\"a}gter stromaler diffuser Hornhauttr{\"u}bung vorgestellt. Patientin 1 war kleinw{\"u}chsig (114 cm) und Patientin 2 normal groß (172 cm). Beide Patientinnen wiesen ver{\"a}nderte Gelenkstrukturen an Hand und Fußgelenken sowie diffuse stromale Hornhauttr{\"u}bungen auf. Des Weiteren lagen eine Mitral- und Aorteninsuffizienz (Patientin 1) bzw. eine Aorteninsuffizienz (Patientin 2) vor. Die stromalen diffusen Hornhauttr{\"u}bungen ließen im Zusammenhang mit den Gelenkver{\"a}nderungen ein Scheie-Syndrom vermuten. Therapeutisch ist bei Patienten mit Visusminderung eine (lamell{\"a}re) Keratoplastik sinnvoll.}, language = {de} } @incollection{LanzlSeidovaDuehringetal.2009, author = {Lanzl, I. and Seidova, S.-F. and D{\"u}hring, C. von and Kotliar, Konstantin}, title = {Befunde der dynamischen Gef{\"a}ßanalyse am Auge bei Gesunden und Glaukom-Patienten mit praxisrelevanter Bedeutung}, series = {Mikrozirkulation beim Glaukom}, booktitle = {Mikrozirkulation beim Glaukom}, editor = {Erb, Carl}, publisher = {Elsevier}, address = {Amsterdam}, pages = {33 -- 39}, year = {2009}, language = {de} } @article{LanzlKotliar2017, author = {Lanzl, I. and Kotliar, Konstantin}, title = {K{\"o}nnen Anti-VEGF-Injektionen Glaukom oder okul{\"a}re Hypertension verursachen?}, series = {Klinische Monatsbl{\"a}tter f{\"u}r Augenheilkunde}, volume = {234}, journal = {Klinische Monatsbl{\"a}tter f{\"u}r Augenheilkunde}, number = {2}, publisher = {Thieme}, address = {Stuttgart}, issn = {0023-2165}, doi = {10.1055/s-0043-101819}, pages = {191 -- 193}, year = {2017}, language = {de} } @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{KurzLinderTrzewiketal.2010, author = {Kurz, R. and Linder, Peter and Trzewik, J{\"u}rgen and R{\"u}ffer, M. and Artmann, Gerhard and Digel, Ilya and Rothermel, A. and Robitzki, A. and Temiz Artmann, Ayseg{\"u}l}, title = {Contractile tension and beating rates of self-exciting monolayers and 3D-tissue constructs of neonatal rat cardiomyocytes}, series = {Medical and Biological Engineering and Computing}, volume = {48}, journal = {Medical and Biological Engineering and Computing}, number = {1}, publisher = {Springer Nature}, address = {Cham}, issn = {1741-0444}, doi = {10.1007/s11517-009-0552-y}, pages = {59 -- 65}, year = {2010}, abstract = {The CellDrum technology (The term 'CellDrum technology' includes a couple of slightly different technological setups for measuring lateral mechanical tension in various types of cell monolayers or 3D-tissue constructs) was designed to quantify the contraction rate and mechanical tension of self-exciting cardiac myocytes. Cells were grown either within flexible, circular collagen gels or as monolayer on top of respective 1-mum thin silicone membranes. Membrane and cells were bulged outwards by air pressure. This biaxial strain distribution is rather similar the beating, blood-filled heart. The setup allowed presetting the mechanical residual stress level externally by adjusting the centre deflection, thus, mimicking hypertension in vitro. Tension was measured as oscillating differential pressure change between chamber and environment. A 0.5-mm thick collagen-cardiac myocyte tissue construct induced after 2 days of culturing (initial cell density 2 x 10(4) cells/ml), a mechanical tension of 1.62 +/- 0.17 microN/mm(2). Mechanical load is an important growth regulator in the developing heart, and the orientation and alignment of cardiomyocytes is stress sensitive. Therefore, it was necessary to develop the CellDrum technology with its biaxial stress-strain distribution and defined mechanical boundary conditions. Cells were exposed to strain in two directions, radially and circumferentially, which is similar to biaxial loading in real heart tissues. Thus, from a biomechanical point of view, the system is preferable to previous setups based on uniaxial stretching.}, language = {en} } @article{KurulganDemirciLinderDemircietal.2009, author = {Kurulgan Demirci, Eylem and Linder, Peter and Demirci, Taylan and Trzewik, J{\"u}rgen and Digel, Ilya and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {Contractile tension of endothelial cells: An LPS based in-vitro sepsis model}, series = {IUBMB Life. 61 (2009), H. 3}, journal = {IUBMB Life. 61 (2009), H. 3}, publisher = {Wiley}, address = {Weinheim}, isbn = {1521-6543}, pages = {307 -- 308}, year = {2009}, language = {en} } @article{KurulganDemirciDemirciLinderetal.2012, author = {Kurulgan Demirci, Eylem and Demirci, Taylan and Linder, Peter and Trzewik, J{\"u}rgen and Gierkowski, Jessica Ricarda and Gossmann, Matthias and Kayser, Peter and Porst, Dariusz and Digel, Ilya and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {rhAPC reduces the endothelial cell permeability via a decrease of contractile tensions induced by endothelial cells}, series = {Journal of Bioscience and Bioengineering}, volume = {113}, journal = {Journal of Bioscience and Bioengineering}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1347-4421}, doi = {10.1016/j.jbiosc.2012.03.019}, pages = {212 -- 219}, year = {2012}, abstract = {All cells generate contractile tension. This strain is crucial for mechanically controlling the cell shape, function and survival. In this study, the CellDrum technology quantifying cell's (the cellular) mechanical tension on a pico-scale was used to investigate the effect of lipopolysaccharide (LPS) on human aortic endothelial cell (HAoEC) tension. The LPS effect during gram-negative sepsis on endothelial cells is cell contraction causing endothelium permeability increase. The aim was to finding out whether recombinant activated protein C (rhAPC) would reverse the endothelial cell response in an in-vitro sepsis model. In this study, the established in-vitro sepsis model was confirmed by interleukin 6 (IL-6) levels at the proteomic and genomic levels by ELISA, real time-PCR and reactive oxygen species (ROS) activation by florescence staining. The thrombin cellular contraction effect on endothelial cells was used as a positive control when the CellDrum technology was applied. Additionally, the Ras homolog gene family, member A (RhoA) mRNA expression level was checked by real time-PCR to support contractile tension results. According to contractile tension results, the mechanical predominance of actin stress fibers was a reason of the increased endothelial contractile tension leading to enhanced endothelium contractility and thus permeability enhancement. The originality of this data supports firstly the basic measurement principles of the CellDrum technology and secondly that rhAPC has a beneficial effect on sepsis influenced cellular tension. The technology presented here is promising for future high-throughput cellular tension analysis that will help identify pathological contractile tension responses of cells and prove further cell in-vitro models.}, 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} } @phdthesis{KurulganDemirci2012, author = {Kurulgan Demirci, Eylem}, title = {The effect of rhAPC on contractile tension : an in-vitro sepsis model of cardiomyocytes and endothelial cells}, year = {2012}, language = {en} } @inproceedings{KuhlenDigel2017, author = {Kuhlen, Max and Digel, Ilya}, title = {Fluorescence signatures and detection limits of ubiquitous terrestrial bio-compounds}, series = {2nd YRA MedTech Symposium 2017 : June 8th - 9th / 2017 / Hochschule Ruhr-West}, booktitle = {2nd YRA MedTech Symposium 2017 : June 8th - 9th / 2017 / Hochschule Ruhr-West}, editor = {Erni, Daniel and Fischerauer, Alice and Himmel, J{\"o}rg and Seeger, Thomas and Thelen, Klaus}, publisher = {Universit{\"a}t Duisburg-Essen}, address = {Duisburg}, organization = {MedTech Symposium}, isbn = {978-3-9814801-9-1}, doi = {10.17185/duepublico/43984}, pages = {102 -- 103}, year = {2017}, language = {en} } @article{KuertenKotliarFuestetal.2021, author = {Kuerten, David and Kotliar, Konstantin and Fuest, Matthias and Walter, Peter and Hollstein, Muriel and Plange, Niklas}, title = {Does hemispheric vascular regulation differ significantly in glaucoma patients with altitudinal visual field asymmetry? A single-center, prospective study}, series = {International Ophthalmology}, volume = {41}, journal = {International Ophthalmology}, number = {41}, editor = {Neri, Piergiorgio}, publisher = {Springer}, address = {Berlin}, isbn = {1573-2630}, doi = {10.1007/s10792-021-01876-0}, pages = {3109 -- 3119}, year = {2021}, abstract = {Purpose Vascular risk factors and ocular perfusion are heatedly discussed in the pathogenesis of glaucoma. The retinal vessel analyzer (RVA, IMEDOS Systems, Germany) allows noninvasive measurement of retinal vessel regulation. Significant differences especially in the veins between healthy subjects and patients suffering from glaucoma were previously reported. In this pilot-study we investigated if localized vascular regulation is altered in glaucoma patients with altitudinal visual field defect asymmetry. Methods 15 eyes of 12 glaucoma patients with advanced altitudinal visual field defect asymmetry were included. The mean defect was calculated for each hemisphere separately (-20.99 ± 10.49 pro- found hemispheric visual field defect vs -7.36 ± 3.97 dB less profound hemisphere). After pupil dilation, RVA measurements of retinal arteries and veins were conducted using the standard protocol. The superior and inferior retinal vessel reactivity were measured consecutively in each eye. Results Significant differences were recorded in venous vessel constriction after flicker light stimulation and overall amplitude of the reaction (p \ 0.04 and p \ 0.02 respectively) in-between the hemispheres spheres. Vessel reaction was higher in the hemisphere corresponding to the more advanced visual field defect. Arterial diameters reacted similarly, failing to reach statistical significance. Conclusion Localized retinal vessel regulation is significantly altered in glaucoma patients with asymmetri altitudinal visual field defects. Veins supplying the hemisphere concordant to a less profound visual field defect show diminished diameter changes. Vascular dysregulation might be particularly important in early glaucoma stages prior to a significant visual field defect.}, language = {en} } @article{KuchlerGuenthnerRibeiroetal.2023, author = {Kuchler, Timon and G{\"u}nthner, Roman and Ribeiro, Andrea and Hausinger, Renate and Streese, Lukas and W{\"o}hnl, Anna and Kesseler, Veronika and Negele, Johanna and Assali, Tarek and Carbajo-Lozoya, Javier and Lech, Maciej and Adorjan, Kristina and Stubbe, Hans Christian and Hanssen, Henner and Kotliar, Konstantin and Haller, Berhard and Heemann, Uwe and Schmaderer, Christoph}, title = {Persistent endothelial dysfunction in post-COVID-19 syndrome and its associations with symptom severity and chronic inflammation}, volume = {26}, publisher = {Springer Nature}, address = {Dordrecht}, doi = {10.1007/s10456-023-09885-6}, pages = {547 -- 563}, year = {2023}, abstract = {Background Post-COVID-19 syndrome (PCS) is a lingering disease with ongoing symptoms such as fatigue and cognitive impairment resulting in a high impact on the daily life of patients. Understanding the pathophysiology of PCS is a public health priority, as it still poses a diagnostic and treatment challenge for physicians. Methods In this prospective observational cohort study, we analyzed the retinal microcirculation using Retinal Vessel Analysis (RVA) in a cohort of patients with PCS and compared it to an age- and gender-matched healthy cohort (n = 41, matched out of n = 204). Measurements and main results PCS patients exhibit persistent endothelial dysfunction (ED), as indicated by significantly lower venular flicker-induced dilation (vFID; 3.42\% ± 1.77\% vs. 4.64\% ± 2.59\%; p = 0.02), narrower central retinal artery equivalent (CRAE; 178.1 [167.5-190.2] vs. 189.1 [179.4-197.2], p = 0.01) and lower arteriolar-venular ratio (AVR; (0.84 [0.8-0.9] vs. 0.88 [0.8-0.9], p = 0.007). When combining AVR and vFID, predicted scores reached good ability to discriminate groups (area under the curve: 0.75). Higher PCS severity scores correlated with lower AVR (R = - 0.37 p = 0.017). The association of microvascular changes with PCS severity were amplified in PCS patients exhibiting higher levels of inflammatory parameters. Conclusion Our results demonstrate that prolonged endothelial dysfunction is a hallmark of PCS, and impairments of the microcirculation seem to explain ongoing symptoms in patients. As potential therapies for PCS emerge, RVA parameters may become relevant as clinical biomarkers for diagnosis and therapy management.}, language = {en} } @article{KraemerDaabMuelleretal.2013, author = {Kr{\"a}mer, Stefan and Daab, Dominique Jonas and M{\"u}ller, Brigitte and Wagner, Tobias and Baader, Fabian and Hessel, Joana and Gdalewitsch, Georg and Plescher, Engelbert and Dachwald, Bernd and Wahle, Michael and Gierse, Andreas and Vetter, Rudolf and Pf{\"u}tzenreuter, Lysan}, title = {Development and flight-testing of a system to isolate vibrations for microgravity experiments on sounding rockets}, series = {21st ESA Symposium on Rocket and Balloon Research}, journal = {21st ESA Symposium on Rocket and Balloon Research}, pages = {1 -- 8}, year = {2013}, language = {en} } @article{KozhalakovaZhubanovaMansurovetal.2010, author = {Kozhalakova, A. A. and Zhubanova, Azhar A. and Mansurov, Z. A. and Digel, Ilya and Tazhibayeva, S. M. and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {Adsorption of bacterial lipopolysaccharides on carbonized rice shell}, series = {Science of Central Asia (2010)}, journal = {Science of Central Asia (2010)}, pages = {50 -- 54}, year = {2010}, language = {en} } @article{KowalskiLinderZierkeetal.2016, author = {Kowalski, Julia and Linder, Peter and Zierke, S. and Wulfen, B. van and Clemens, J. and Konstantinidis, K. and Ameres, G. and Hoffmann, R. and Mikucki, J. and Tulaczyk, S. and Funke, O. and Blandfort, D. and Espe, Clemens and Feldmann, Marco and Francke, Gero and Hiecker, S. and Plescher, Engelbert and Sch{\"o}ngarth, Sarah and Dachwald, Bernd and Digel, Ilya and Artmann, Gerhard and Eliseev, D. and Heinen, D. and Scholz, F. and Wiebusch, C. and Macht, S. and Bestmann, U. and Reineking, T. and Zetzsche, C. and Schill, K. and F{\"o}rstner, R. and Niedermeier, H. and Szumski, A. and Eissfeller, B. and Naumann, U. and Helbing, K.}, title = {Navigation technology for exploration of glacier ice with maneuverable melting probes}, series = {Cold Regions Science and Technology}, journal = {Cold Regions Science and Technology}, number = {123}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0165-232X}, doi = {10.1016/j.coldregions.2015.11.006}, pages = {53 -- 70}, year = {2016}, abstract = {The Saturnian moon Enceladus with its extensive water bodies underneath a thick ice sheet cover is a potential candidate for extraterrestrial life. Direct exploration of such extraterrestrial aquatic ecosystems requires advanced access and sampling technologies with a high level of autonomy. A new technological approach has been developed as part of the collaborative research project Enceladus Explorer (EnEx). The concept is based upon a minimally invasive melting probe called the IceMole. The force-regulated, heater-controlled IceMole is able to travel along a curved trajectory as well as upwards. Hence, it allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. The development of such a navigational system has been the focal part of the EnEx project. The original IceMole has been further developed to include relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection integrated through a high-level sensor fusion. This paper describes the EnEx technology and discusses implications for an actual extraterrestrial mission concept.}, language = {en} } @article{KotliarVilserNageletal.2004, author = {Kotliar, Konstantin and Vilser, Walthatd and Nagel, Edgar and Lanzl, Ines M.}, title = {Retinal vessel reaction in response to chromatic flickering light / Kotliar, Konstantin E. ; Vilser, Walthard ; Nagel, Edgar ; Lanzl, Ines M.}, series = {Graefe's Archive for Clinical and Experimental Ophthalmology. 242 (2004), H. 5}, journal = {Graefe's Archive for Clinical and Experimental Ophthalmology. 242 (2004), H. 5}, publisher = {-}, isbn = {1435-702X}, pages = {377 -- 392}, year = {2004}, language = {en} } @article{KotliarVilserSchmidtTrucksaessetal.2009, author = {Kotliar, Konstantin and Vilser, W. and Schmidt-Trucks{\"a}ss, A. and Halle, M. and Lanzl, I. M.}, title = {Zeitliche Schwingungen retinaler Gef{\"a}ßdurchmesser bei Gesunden unterschiedlichen Alters : Kreuz- und Autokorrelation f{\"u}r dynamische Gef{\"a}ßanalyse}, series = {Der Ophthalmologe}, volume = {106}, journal = {Der Ophthalmologe}, number = {7}, publisher = {-}, isbn = {1433-0423}, pages = {609 -- 618}, year = {2009}, language = {de} } @article{KotliarSvetlovaStegaevetal.2004, author = {Kotliar, Konstantin and Svetlova, O. V. and Stegaev, V. A. and Parkhomov, S. D.}, title = {Biomechanical substantiation of relatively low efficiency of recurrent laser trabeculoplasty / Svetlova, O. V. ; Stagaev, V. A. ; Parkhomov, S. D. ; Kotliar, K. E. ; Makarov, F. N. ; Smolnikov, B. A. ; Koshitz, I. N.}, series = {Glaukoma (2004)}, journal = {Glaukoma (2004)}, publisher = {-}, pages = {29 -- 39}, year = {2004}, language = {en} } @article{KotliarSvetlovaSourjikovetal.2004, author = {Kotliar, Konstantin and Svetlova, O. V. and Sourjikov, A. V. and Zaseeva, M. V.}, title = {Biomechanical peculiarities of aqueous humor production system and outflow regulation system / Svetlova, O. V. ; Sourjikov, A. V. ; Kotliar, K. E. ; Zaseeva, M. V. ; Shukhaev, S. V. ; Koshitz, I. N.}, series = {Glaukoma (2004)}, journal = {Glaukoma (2004)}, publisher = {-}, pages = {66 -- 76}, year = {2004}, language = {en} } @article{KotliarSvetlovaMakarovetal.2003, author = {Kotliar, Konstantin and Svetlova, O. V. and Makarov, F. N. and Zaseeva, M. V.}, title = {Morfologicheskie i funktsional'nye osobennosti resnichnogo poiaska khrustalika kak kliuchevogo ispolnitel'nogo zvena v mekhanizme akkommodatsii glaza cheloveka = Morpho-functional characteristics of lens ciliary body as a key mechanism of accommodation in}, series = {Morfologiia (Saint Petersburg, Russia). 123 (2003), H. 3}, journal = {Morfologiia (Saint Petersburg, Russia). 123 (2003), H. 3}, publisher = {-}, isbn = {1026-3543}, pages = {7 -- 16}, year = {2003}, language = {en} } @article{KotliarOrtnerConradietal.2022, author = {Kotliar, Konstantin and Ortner, Marion and Conradi, Anna and Hacker, Patricia and Hauser, Christine and G{\"u}nthner, Roman and Moser, Michaela and Muggenthaler, Claudia and Diehl-Schmid, Janine and Priller, Josef and Schmaderer, Christoph and Grimmer, Timo}, title = {Altered retinal cerebral vessel oscillation frequencies in Alzheimer's disease compatible with impaired amyloid clearance}, series = {Neurobiology of Aging}, volume = {120}, journal = {Neurobiology of Aging}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0197-4580}, doi = {10.1016/j.neurobiolaging.2022.08.012}, pages = {117 -- 127}, year = {2022}, abstract = {Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis.}, language = {en} } @article{KotliarNagelVilseretal.2010, author = {Kotliar, Konstantin and Nagel, Edgar and Vilser, Walthard and Seidova, Seid-Fatima and Lanzl, Ines}, title = {Microstructural alterations of retinal arterial blood column along the vessel axis in systemic hypertension}, series = {Investigative Ophthalmology \& Visual Science, IOVS}, volume = {51}, journal = {Investigative Ophthalmology \& Visual Science, IOVS}, number = {4}, publisher = {ARVO}, address = {Rockville, Md.}, issn = {0146-0404}, doi = {10.1167/iovs.09-3649}, pages = {2165 -- 2172}, year = {2010}, abstract = {Purpose: Image analysis by the retinal vessel analyzer (RVA) observes retinal vessels in their dynamic state online noninvasively along a chosen vessel segment. It has been found that high-frequency diameter changes in the retinal artery blood column along the vessel increase significantly in anamnestically healthy volunteers with increasing age and in patients with glaucoma during vascular dilation. This study was undertaken to investigate whether longitudinal sections of the retinal artery blood column are altered in systemic hypertension. Methods: Retinal arteries of 15 untreated patients with essential arterial hypertension (age, 50.9 ± 11.9 years) and of 15 age-matched anamnestically healthy volunteers were examined by RVA. After baseline assessment, a monochromatic luminance flicker (530-600 nm; 12.5 Hz; 20 s) was applied to evoke retinal vasodilation. Differences in amplitude and frequency of spatial artery blood column diameter change along segments (longitudinal arterial profiles) of 1 mm in length were measured and analyzed using Fourier transformation. Results: In the control group, average reduced power spectra (ARPS) of longitudinal arterial profiles did not differ when arteries changed from constriction to dilation. In the systemic hypertension group, ARPS during constriction, baseline, and restoration were identical and differed from ARPS during dilation (P < 0.05). Longitudinal arterial profiles in both groups showed significant dissimilitude at baseline and restoration (P < 0.05). Conclusions: The retinal artery blood column demonstrates microstructural alterations in systemic hypertension and is less irregular along the vessel axis during vessel dilation. These microstructural changes may be an indication of alterations in vessel wall rigidity, vascular endothelial function, and smooth muscle cells in this disease, leading to impaired perfusion and regulation.}, 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{KotliarMueckeVilseretal.2008, author = {Kotliar, Konstantin and M{\"u}cke, Bruno and Vilser, Walthard and Schilling, Rudolf}, title = {Effect of aging on retinal artery blood column diameter measured along the vessel axis / Kotliar, Konstantin E. ; M{\"u}cke, Bruno ; Vilser, Walthard ; Schilling, Rudolf ; Lanzl, Ines M.}, series = {Investigative Ophthalmology \& Visual Science, IOVS. 49 (2008), H. 5}, journal = {Investigative Ophthalmology \& Visual Science, IOVS. 49 (2008), H. 5}, publisher = {-}, isbn = {0146-0404}, pages = {2094 -- 2102}, year = {2008}, language = {en} } @article{KotliarMogilevskiĭShiloetal.2008, author = {Kotliar, Konstantin and Mogilevskiĭ, A. Ia. and Shilo, A. V. and Panchekha, A. P.}, title = {[Chaotic non-linear dynamics of alpha-band of the EEg and organization of the cortical activity of P300 wave] / Mogilevskiĭ, A. Ia. ; Kotliar, K. E. ; Shilo, A. V. ; Panchekha, A. P.}, series = {Zhurnal vyssheĭ nervnoĭ deiatelnosti imeni I P Pavlova. 58 (2008), H. 5}, journal = {Zhurnal vyssheĭ nervnoĭ deiatelnosti imeni I P Pavlova. 58 (2008), H. 5}, publisher = {-}, isbn = {0044-4677}, pages = {562 -- 575}, year = {2008}, language = {en} } @article{KotliarMaierBaueretal.2008, author = {Kotliar, Konstantin and Maier, Mathias and Bauer, Svetlana and Feucht, Nikolaus and Lohmann, Chris and Lanzl, Ines}, title = {Intravitreal injection of triamcinolone acetonide and intraocular pressure: author's reply}, series = {Acta Ophthalmologica}, volume = {86}, journal = {Acta Ophthalmologica}, number = {6}, publisher = {-}, isbn = {1755-3768}, pages = {692 -- 693}, year = {2008}, language = {en} } @article{KotliarMaierBaueretal.2007, author = {Kotliar, Konstantin and Maier, Mathias and Bauer, Svetlana and Feucht, Nikolaus}, title = {Effect of intravitreal injections and volume changes on intraocular pressure: clinical results and biomechanical model / Kotliar, Konstantin ; Maier, Mathias ; Bauer, Svetlana ; Feucht, Nikolaus ; Lohmann, Chris ; Lanzl, Ines}, series = {Acta Ophthalmologica Scandinavica. 85 (2007), H. 7}, journal = {Acta Ophthalmologica Scandinavica. 85 (2007), H. 7}, publisher = {-}, isbn = {1755-3768}, pages = {777 -- 781}, year = {2007}, language = {en} } @article{KotliarLanzlSchmidtTrucksaessetal.2011, author = {Kotliar, Konstantin and Lanzl, Ines M. and Schmidt-Trucks{\"a}ss, A. and Sitnikova, Diana and Ali, Mohammad and Blume, Katharina and Halle, Martin and Hansser, Henner}, title = {Dynamic retinal vessel response to flicker in obesity: A methodological approach}, series = {Microvascular Research}, volume = {81}, journal = {Microvascular Research}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0026-2862}, pages = {123 -- 128}, year = {2011}, language = {en} } @article{KotliarLanzlMaieretal.2008, author = {Kotliar, Konstantin and Lanzl, Ines M. and Maier, Mathias and Feucht, Nikolaus}, title = {Intraocular pressure effects of pegaptanib (macugen) injections in patients with and without glaucoma / Lanzl, Ines M. ; Maier, Mathias ; Feucht, Nikolaus ; Lohmann, Chris P. ; Kotliar, Konstantin E.}, series = {American Journal of Ophthalmology . 145 (2008), H. 1}, journal = {American Journal of Ophthalmology . 145 (2008), H. 1}, publisher = {-}, isbn = {1879-1891}, pages = {185 -- 185}, year = {2008}, language = {en} } @article{KotliarLanzlHanssenetal.2012, author = {Kotliar, Konstantin and Lanzl, Ines M. and Hanssen, Henner and Eberhardt, Karla and Vilser, Walthard and Halle, Martin and Heemann, Uwe and Schmidt-Trucks{\"a}ss, Arno and Baumann, Marcus}, title = {Does increased blood pressure rather than aging influence retinal pulse wave velocity?}, series = {Investigative Ophthalmology \& Visual Science, IOVS}, volume = {53}, journal = {Investigative Ophthalmology \& Visual Science, IOVS}, number = {4}, publisher = {ARVO}, address = {Rockville, Md.}, issn = {0146-0404}, doi = {10.1167/iovs.11-8815}, pages = {2119 -- 2126}, year = {2012}, abstract = {Purpose: It was demonstrated previously that retinal pulse wave velocity (rPWV) as a measure of retinal arterial stiffness is increased in aged anamnestically healthy volunteers compared with young healthy subjects. Using novel methodology of rPWV assessment this finding was confirmed and investigated whether it might relate to the increased blood pressure usually accompanying the aging process, rather than to the aging itself. Methods: A total of 12 young 25.5-year-old (24.0-28.8) [median(1st quartile-3rd quartile)] and 12 senior 68.5-year-old (63.8-71.8) anamnestically healthy volunteers; and 12 senior 63.0-year-old (60.8-65.0) validated healthy volunteers and 12 young 33.0-year-old (29.5-35.0) hypertensive patients were examined. Time-dependent alterations of vessel diameter were assessed by the Dynamic Vessel Analyzer in a retinal artery of each subject. The data were filtered and processed using mathematical signal analysis and rPWVs were calculated. Results: rPWV amounted to 1200 (990-1470) RU (relative units)/s in the hypertensive group and to 1040 (700-2230) RU/s in anamnestically healthy seniors. These differed significantly from rPWVs in young healthy group (410 [280-500] RU/s) and in validated healthy seniors (400 [320-510] RU/s). rPWV associated with age and mean arterial pressure (MAP) in the pooled cohort excluded validated healthy seniors. In a regression model these associations remain when alternately adjusted for MAP and age. When including validated healthy seniors in the pooled cohort only association with MAP remains. Conclusions: Both aging (with not excluded cardiovascular risk factors) and mild hypertension are associated with elevated rPWV. rPWV increases to a similar extent both in young mildly hypertensive subjects and in aged anamnestically healthy persons. Healthy aging is not associated with increased rPWV.}, language = {en} } @article{KotliarLanzl2011, author = {Kotliar, Konstantin and Lanzl, Ines M.}, title = {Can vascular function be assessed by the interpretation of retinal vascular diameter changes?}, series = {Investigative Ophthalmology \& Visual Science, IOVS. 52 (2011), H. 1}, journal = {Investigative Ophthalmology \& Visual Science, IOVS. 52 (2011), H. 1}, publisher = {ARVO}, address = {Rockville, Md.}, isbn = {0146-0404}, pages = {635 -- 636}, year = {2011}, language = {en} } @article{KotliarLanzl2018, author = {Kotliar, Konstantin and Lanzl, Ines}, title = {Vaskul{\"a}re Biomarker der retinalen Gef{\"a}βanalyse}, series = {Klinische Monatsbl{\"a}tter fur Augenheilkunde}, volume = {235}, journal = {Klinische Monatsbl{\"a}tter fur Augenheilkunde}, number = {12}, publisher = {Thieme}, address = {Stuttgart}, issn = {0023-2165}, doi = {10.1055/a-0774-7987}, pages = {1352 -- 1359}, year = {2018}, abstract = {Mit modernen nicht invasiven bildgebenden Verfahren lassen sich anhand der Fundusfotografie bzw. der optischen Verfilmung Aspekte der funktionellen und strukturellen retinalen Gef{\"a}ßver{\"a}nderungen objektiv untersuchen. Der Zustand und das Verhalten retinaler Gef{\"a}ße beeinflussen im pr{\"a}-, post- und kapillaren Bereich den Blutfluss und str{\"o}mungsbedingte Stoffwechselverh{\"a}ltnisse passiv und aktiv {\"u}ber den Gef{\"a}ßdurchmesser. Retinale Gef{\"a}ße gleichen von Aufbau und Funktion den zerebralen Gef{\"a}ßen und spiegeln den Zustand der Mikrozirkulation wider. Mithilfe von aus den Gef{\"a}ßweiten berechneten Biomarkern soll eine Aussage {\"u}ber die Prognose von systemischen vaskul{\"a}r bedingten Erkrankungen getroffen werden. Die statische retinale Gef{\"a}ßanalyse befasst sich mit der Untersuchung des Zustandes der pr{\"a}- und postkapillaren Gef{\"a}ßdurchmesser der retinalen Mikrozirkulation anhand einer optischen Fundusaufnahme. Bei der dynamischen retinalen Gef{\"a}ßanalyse wird der L{\"a}ngsschnitt eines retinalen Gef{\"a}ßes nicht invasiv funktionell und strukturell {\"u}ber einen Zeitraum vor, w{\"a}hrend und nach einer spezifischen vaskul{\"a}ren Stimulation untersucht. Die genaue Methodologie der Auswertung und die Bezeichnung der Parameter variieren bei unterschiedlichen Ans{\"a}tzen. Mittels retinaler Gef{\"a}ßanalyse wurden bislang mehrere klinische Querschnitts- und Interventionsstudien in der Augenheilkunde und anderen Fachgebieten, inkl. Kardiologie, Neurologie, Neurochirurgie, Nephrologie, Gyn{\"a}kologie, Sportmedizin, Diabetologie, Hypertensiologie usw. durchgef{\"u}hrt. Mit der statischen retinalen Gef{\"a}ßanalyse steht eine kosteng{\"u}nstige, reproduzierbare, nicht invasive Screeningtechnik zur Verf{\"u}gung, um eine prognostische Aussage {\"u}ber die Gef{\"a}ßgesundheit eines individuellen Patienten zu treffen. Die dynamische retinale Gef{\"a}ßanalyse besitzt ein weiteres diagnostisches Anwendungsspektrum als die statische, da sie das Verhalten retinaler Gef{\"a}ße zeitkontinuierlich untersucht. Die Evaluation vaskul{\"a}rer Erkrankungen sowie zerebro- bzw. kardiovaskul{\"a}rer Morbidit{\"a}t und Mortalit{\"a}t mittels mehrerer methodologischer Modalit{\"a}ten retinaler Gef{\"a}ßanalyse mit ihren jeweiligen quantitativen Biomarkern bietet eine zukunftstr{\"a}chtige diagnostische Perspektive. Die interdisziplin{\"a}re klinische Anwendung dieser vaskul{\"a}ren Biomarker gewinnt zunehmend an Bedeutung, sowohl in der Augenheilkunde als auch in anderen Fachgebieten.}, language = {de} } @article{KotliarLanzl2002, author = {Kotliar, Konstantin and Lanzl, I. M.}, title = {Biomechanical modeling of the aqueous humor outflow after non-penetrating glaucoma filtration surgery in the human eye}, series = {Acta of bioengineering and biomechanics}, volume = {Vol. 4}, journal = {Acta of bioengineering and biomechanics}, number = {Suppl. 1}, issn = {1509-409X}, pages = {728 -- 729}, year = {2002}, language = {de} } @article{KotliarLanzl2016, author = {Kotliar, Konstantin and Lanzl, I. M.}, title = {Mit Statistik gemeistert: perfekte Augentropfen und idealer Screeningtest : M{\"o}glichkeiten und Grenzen statistischer Methoden beim Glaukom}, series = {Der Ophthalmologe: Zeitschrift Der Deutschen Ophthalmologischen Gesellschaft}, journal = {Der Ophthalmologe: Zeitschrift Der Deutschen Ophthalmologischen Gesellschaft}, number = {113}, publisher = {Springer}, address = {Berlin}, issn = {0941-293X}, doi = {10.1007/s00347-016-0312-y}, pages = {838 -- 843}, year = {2016}, abstract = {Hintergrund Die Anwendung und das Verst{\"a}ndnis von Statistik sind sehr wichtig f{\"u}r die biomedizinische Forschung und f{\"u}r die klinische Praxis. Dies gilt insbesondere auch zur Absch{\"a}tzung der M{\"o}glichkeiten unterschiedlichster Diagnostik- und Therapieoptionen beim Glaukom. Die scheinbare Komplexit{\"a}t der Statistik, die zum Teil dem „gesunden Menschenverstand" zu widersprechen scheint, zusammen mit der nur vorsichtigen Akzeptanz der Statistik bei vielen Medizinern k{\"o}nnen zu bewussten und unbewussten Manipulationen bei der Datendarstellung und -interpretation f{\"u}hren. Ziel der Arbeit Ziel ist die verst{\"a}ndliche Darstellung einiger typischer Fehler in der medizinisch-statistischen Datenbehandlung. Material und Methoden Anhand hypothetischer Beispiele aus der Glaukomdiagnostik erfolgen die Darstellung der Wirkung eines hypotensiven Medikamentes sowie die Beurteilung der Ergebnisse eines diagnostischen Tests. Es werden die typischsten statistischen Einsatzbereiche und Irrtumsquellen ausf{\"u}hrlich und verst{\"a}ndlich analysiert Ergebnisse Mechanismen von Datenmanipulation und falscher Dateninterpretation werden aufgekl{\"a}rt. Typische Irrtumsquellen bei der statistischen Auswertung und Datendarstellung werden dabei erl{\"a}utert. Schlussfolgerungen Die erl{\"a}uterten praktischen Beispiele zeigen die Notwendigkeit, die Grundlagen der Statistik zu verstehen und korrekt anwenden zu k{\"o}nnen. Fehlendes Grundlagenwissen und Halbwissen der medizinischen Statistik k{\"o}nnen zu folgenschweren Missverst{\"a}ndnissen und falschen Entscheidungen in der medizinischen Forschung, aber auch in der klinischen Praxis f{\"u}hren.}, language = {de} } @article{KotliarKozlovaLanzl2009, author = {Kotliar, Konstantin and Kozlova, Tatiana V. and Lanzl, Ines M.}, title = {Postoperative aqueous outflow in the human eye after glaucoma filtration surgery: biofluidmechanical considerations}, series = {Biomedizinische Technik = Biomedical Engineering}, volume = {54}, journal = {Biomedizinische Technik = Biomedical Engineering}, number = {1}, publisher = {-}, isbn = {1862-278X}, pages = {14 -- 22}, year = {2009}, language = {en} } @article{KotliarKoshitzSvetlowaetal.2006, author = {Kotliar, Konstantin and Koshitz, I. N. and Svetlowa, O. V. and Zaseeva, M. V.}, title = {Physiological principles of hypotensive therapy of open-angle glaucoma during presbyopic period. Part II Promising algorithms of practical sparing applications / Koshitz, I. N. ; Svetlova, O. V. ; Zaseeva, M. V. ; Shuhaev, S. V. ; Makarov, F. N. ; Kotliar}, series = {Glaukoma (2006)}, journal = {Glaukoma (2006)}, publisher = {-}, pages = {51 -- 70}, year = {2006}, language = {en} } @article{KotliarKoshitzSvetlowaetal.2005, author = {Kotliar, Konstantin and Koshitz, I. N. and Svetlowa, O. V. and Makarov, F. N.}, title = {Biomechanical analysis of traditional and contemporary conceptions on pathogenesis of the primary open angle glaucoma / Koshitz, I. N. ; Svetlova, O. V. ; Kotliar, K. E. ; Makarov, F. N. ; Smolnikov, B. A.}, series = {Glaukoma (2005)}, journal = {Glaukoma (2005)}, publisher = {-}, pages = {41 -- 63}, year = {2005}, language = {en} } @article{KotliarKoshitzSvetlovaetal.2006, author = {Kotliar, Konstantin and Koshitz, I. N. and Svetlova, O. V. and Zaseeva, M. V.}, title = {Physiological principles of hypotensive therapy of open-angle glaucoma during presbyopic period. Part I Initial theoretical presuppositions, hypotheses and facts / Koshitz, I. N. ; Svetlova, O. V. ; Zaseeva, M. V. ; Shuhaev, S. V. ; Makarov, F. N. ; Kotli}, series = {Glaukoma (2006)}, journal = {Glaukoma (2006)}, publisher = {-}, pages = {35 -- 53}, year = {2006}, language = {en} } @article{KotliarKharoubiSchmidtTrucksaessetal.2009, author = {Kotliar, Konstantin and Kharoubi, A. and Schmidt-Trucks{\"a}ß, A. and Halle, M. and Lanzl, I.}, title = {Does internal longitudinal microstructure of retinal veins change with age in medically healthy persons?}, series = {Acta Ophthalmologica}, volume = {Vol. 87}, journal = {Acta Ophthalmologica}, number = {Suppl. S244}, publisher = {Wiley}, address = {Weinheim}, issn = {1600-0420 (E-Journal); 1755-3768 (E-Journal); 0001-639X (Print); 1395-3907 (Print); 1755-375X (Print)}, pages = {0}, year = {2009}, language = {en} } @article{KotliarHauserOrtneretal.2017, author = {Kotliar, Konstantin and Hauser, Christine and Ortner, Marion and Muggenthaler, Claudia and Diehl-Schmid, Janine and Angermann, Susanne and Hapfelmeier, Alexander and Schmaderer, Christoph and Grimmer, Timo}, title = {Altered neurovascular coupling as measured by optical imaging: a biomarker for Alzheimer's disease}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, number = {1}, publisher = {Springer Nature}, address = {Cham}, issn = {2045-2322}, doi = {10.1038/s41598-017-13349-5}, pages = {1 -- 11}, year = {2017}, language = {en} } @article{KotliarHanssenEberhardtetal.2013, author = {Kotliar, Konstantin and Hanssen, Henner and Eberhardt, Karla and Vilser, Walthard and Schmaderer, Christoph and Halle, Martin and Heemann, Uwe and Baumann, M.}, title = {Retinal pulse wave velocity in young male normotensive and mildly hypertensive subjects}, series = {Microcirculation}, journal = {Microcirculation}, publisher = {Wiley}, address = {Malden}, issn = {1549-8719}, year = {2013}, language = {en} } @article{KotliarDrozdovaShamshinova2006, author = {Kotliar, Konstantin and Drozdova, G. A. and Shamshinova, A. M.}, title = {Ocular hemodinamics and contemporary methods of its assessment.
 Part I. Ocular blood circulation and its quantitative estimation}, series = {National journal Glaucoma}, volume = {Vol. 5}, journal = {National journal Glaucoma}, number = {No. 3}, issn = {2078-4104}, pages = {62 -- 73}, year = {2006}, language = {ru} } @article{KotliarDrozdovaShamshinova2007, author = {Kotliar, Konstantin and Drozdova, G. A. and Shamshinova, A. M.}, title = {Ocular hemodinamics and contemporary methods of its assessment. Part III. Non-invasive methods of assessment of ocular blood flow. 2. Static and dynamic assessment of retinal vessel reaction to stimuli}, series = {National Journal Glaucoma}, volume = {Vol. 6}, journal = {National Journal Glaucoma}, number = {No. 2}, issn = {2078-4104}, pages = {64 -- 71}, year = {2007}, language = {ru} } @article{KotliarDrozdovaShamshinova2007, author = {Kotliar, Konstantin and Drozdova, G. A. and Shamshinova, A. M.}, title = {Ocular hemodinamics and contemporary methods of its assessment. Part III. Non-invasive methods of assessment of ocular blood flow. 1. Assessment of blood cell velocities and flow rates in intraocular vessels and vascular beds}, series = {Journal of Glaucoma}, volume = {Vol. 6}, journal = {Journal of Glaucoma}, number = {1}, issn = {2078-4104}, pages = {61 -- 68}, year = {2007}, language = {ru} } @article{KotliarDrozdovaShamshinova2006, author = {Kotliar, Konstantin and Drozdova, G. A. and Shamshinova, A. M.}, title = {Ocular hemodinamics and contemporary methods of its assessment. Part II. Invasive methods of assessment of ocular blood flow}, series = {National Journal Glaucoma}, volume = {Vol. 5}, journal = {National Journal Glaucoma}, number = {No. 4}, issn = {2078-4104}, pages = {37 -- 49}, year = {2006}, language = {ru} } @article{KotliarBaumannVilseretal.2011, author = {Kotliar, Konstantin and Baumann, Marcus and Vilser, Walthard and Lanzl, Ines M.}, title = {Pulse wave velocity in retinal arteries of healthy volunteers}, series = {British Journal of Ophthalmology (eBJO)}, volume = {95}, journal = {British Journal of Ophthalmology (eBJO)}, number = {11}, publisher = {BMJ Publ. Group}, address = {London}, isbn = {1468-2079}, pages = {675 -- 679}, year = {2011}, language = {en} } @article{KotliarBauerZamuraev2006, author = {Kotliar, Konstantin and Bauer, S. M. and Zamuraev, L. A.}, title = {Model of the transversely isotropic spherical layer for estimation of intraocular pressure changes after intravitreal injections / Bauer, S. M. ; Zamuraev, L. A. ; Kotliar, K. E.}, series = {Rossiiskii zhurnal biomekhaniki = Russian Journal of biomechanics. 10 (2006), H. 2}, journal = {Rossiiskii zhurnal biomekhaniki = Russian Journal of biomechanics. 10 (2006), H. 2}, publisher = {-}, isbn = {1812-5123}, pages = {41 -- 47}, year = {2006}, language = {en} } @phdthesis{Kotliar2012, author = {Kotliar, Konstantin}, title = {Pathophysiologische Beurteilung und h{\"a}modynamische Analyse von mikrostrukturellen Ver{\"a}nderungen des retinalen Gef{\"a}ßl{\"a}ngsschnittsprofils}, pages = {328 S.}, year = {2012}, language = {ru} } @phdthesis{Kotliar2008, author = {Kotliar, Konstantin}, title = {Functional in-vivo assessment and biofluidmechanical analysis of age-related and pathological microstructural changes in retinal vessels [Elektronische Ressource]}, publisher = {-}, year = {2008}, language = {en} } @phdthesis{Kotliar2013, author = {Kotliar, Konstantin}, title = {Dynamische retinale Gef{\"a}ßanalyse f{\"u}r die Diagnostik und Fr{\"u}herkennung von System- und Augenerkrankungen vaskul{\"a}rer Genese}, pages = {128 Bl.}, year = {2013}, language = {de} } @incollection{Kotliar2021, author = {Kotliar, Konstantin}, title = {Ocular rigidity: clinical approach}, series = {Ocular Rigidity, Biomechanics and Hydrodynamics of the Eye}, booktitle = {Ocular Rigidity, Biomechanics and Hydrodynamics of the Eye}, editor = {Pallikaris, I. and Tsilimbaris, M. K. and Dastiridou, A. I.}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-64422-2}, doi = {10.1007/978-3-030-64422-2_2}, pages = {15 -- 43}, year = {2021}, abstract = {The term ocular rigidity is widely used in clinical ophthalmology. Generally it is assumed as a resistance of the whole eyeball to mechanical deformation and relates to biomechanical properties of the eye and its tissues. Basic principles and formulas for clinical tonometry, tonography and pulsatile ocular blood flow measurements are based on the concept of ocular rigidity. There is evidence for altered ocular rigidity in aging, in several eye diseases and after eye surgery. Unfortunately, there is no consensual view on ocular rigidity: it used to make a quite different sense for different people but still the same name. Foremost there is no clear consent between biomechanical engineers and ophthalmologists on the concept. Moreover ocular rigidity is occasionally characterized using various parameters with their different physical dimensions. In contrast to engineering approach, clinical approach to ocular rigidity claims to characterize the total mechanical response of the eyeball to its deformation without any detailed considerations on eye morphology or material properties of its tissues. Further to the previous chapter this section aims to describe clinical approach to ocular rigidity from the perspective of an engineer in an attempt to straighten out this concept, to show its advantages, disadvantages and various applications.}, 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{KoppSchmeetsGosauetal.2019, author = {Kopp, Alexander and Schmeets, Ralf and Gosau, Martin and Friedrich, Reinhard E. and Fuest, Sandra and Behbahani, Mehdi and Barbeck, Mike and Rutkowski, Rico and Burg, Simon and Kluwe, Lan and Henningsen, Anders}, title = {Production and Characterization of Porous Fibroin Scaffolds for Regenerative Medical Application}, series = {In Vivo}, volume = {33}, journal = {In Vivo}, number = {3}, issn = {1791-7549}, doi = {10.21873/invivo.11536}, pages = {757 -- 762}, year = {2019}, language = {en} } @article{KonstantinidisFloresMartinezDachwaldetal.2015, author = {Konstantinidis, Konstantinos and Flores Martinez, Claudio and Dachwald, Bernd and Ohndorf, Andreas and Dykta, Paul and Bowitz, Pascal and Rudolph, Martin and Digel, Ilya and Kowalski, Julia and Voigt, Konstantin and F{\"o}rstner, Roger}, title = {A lander mission to probe subglacial water on Saturn's moon enceladus for life}, series = {Acta astronautica}, volume = {Vol. 106}, journal = {Acta astronautica}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2030 (E-Journal); 0094-5765 (Print)}, pages = {63 -- 89}, year = {2015}, language = {en} } @inproceedings{KonstantinidisKowalskiMartinezetal.2015, author = {Konstantinidis, K. and Kowalski, Julia and Martinez, C. F. and Dachwald, Bernd and Ewerhart, D. and F{\"o}rstner, R.}, title = {Some necessary technologies for in-situ astrobiology on enceladus}, series = {Proceedings of the International Astronautical Congress}, booktitle = {Proceedings of the International Astronautical Congress}, isbn = {978-151081893-4}, pages = {1354 -- 1372}, year = {2015}, language = {en} } @inproceedings{KonstantinidisDachwaldOhndorfetal.2013, author = {Konstantinidis, K. and Dachwald, Bernd and Ohndorf, A. and Dykta, P. and Voigt, K. and F{\"o}rstner, R.}, title = {Enceladus explorer (ENEX): A lander mission to probe subglacial water pockets on Saturn's moon enceladus for life}, series = {64th International Astronautical Congress 2013 (IAC 2013) : Beijing, China, 23 - 27 September 2013. (Proceedings of the International Astronautical Congress, IAC ; 2)}, booktitle = {64th International Astronautical Congress 2013 (IAC 2013) : Beijing, China, 23 - 27 September 2013. (Proceedings of the International Astronautical Congress, IAC ; 2)}, publisher = {Curran}, address = {Red Hook, NY}, organization = {International Astronautical Congress <64, 2013, Beijing>}, isbn = {978-1-62993-909-4}, pages = {1340 -- 1350}, year = {2013}, language = {en} } @inproceedings{KolditzAlbrachtFasseetal.2015, author = {Kolditz, Melanie and Albracht, Kirsten and Fasse, Alessandro and Albin, Thivaharan and Br{\"u}ggemann, Gert-Peter and Abel, Dirk}, title = {Evaluation of an industrial robot as a leg press training device}, series = {XV International Symposium on Computer Simulation in Biomechanics July 9th - 11th 2015, Edinburgh, UK}, booktitle = {XV International Symposium on Computer Simulation in Biomechanics July 9th - 11th 2015, Edinburgh, UK}, pages = {41 -- 42}, year = {2015}, language = {en} } @inproceedings{KolditzAlbinFasseetal.2015, author = {Kolditz, Melanie and Albin, Thivaharan and Fasse, Alessandro and Br{\"u}ggemann, Gert-Peter and Abel, Dirk and Albracht, Kirsten}, title = {Simulative Analysis of Joint Loading During Leg Press Exercise for Control Applications}, series = {IFAC-PapersOnLine}, volume = {48}, booktitle = {IFAC-PapersOnLine}, number = {20}, doi = {10.1016/j.ifacol.2015.10.179}, pages = {435 -- 440}, year = {2015}, language = {en} } @article{KolditzAlbinBrueggemannetal.2016, author = {Kolditz, Melanie and Albin, Thivaharan and Br{\"u}ggemann, Gert-Peter and Abel, Dirk and Albracht, Kirsten}, title = {Robotergest{\"u}tztes System f{\"u}r ein verbessertes neuromuskul{\"a}res Aufbautraining der Beinstrecker}, series = {at - Automatisierungstechnik}, volume = {64}, journal = {at - Automatisierungstechnik}, number = {11}, publisher = {De Gruyter}, address = {Berlin}, issn = {2196-677X}, doi = {10.1515/auto-2016-0044}, pages = {905 -- 914}, year = {2016}, abstract = {Neuromuskul{\"a}res Aufbautraining der Beinstrecker ist ein wichtiger Bestandteil in der Rehabilitation und Pr{\"a}vention von Muskel-Skelett-Erkrankungen. Effektives Training erfordert hohe Muskelkr{\"a}fte, die gleichzeitig hohe Belastungen von bereits gesch{\"a}digten Strukturen bedeuten. Um trainingsinduzierte Sch{\"a}digungen zu vermeiden, m{\"u}ssen diese Kr{\"a}fte kontrolliert werden. Mit heutigen Trainingsger{\"a}ten k{\"o}nnen diese Ziele allerdings nicht erreicht werden. F{\"u}r ein sicheres und effektives Training sollen durch den Einsatz der Robotik, Sensorik, eines Regelkreises sowie Muskel-Skelett-Modellen Belastungen am Zielgewebe direkt berechnet und kontrolliert werden. Auf Basis zweier Vorstudien zu m{\"o}glichen Stellgr{\"o}ßen wird der Aufbau eines robotischen Systems vorgestellt, das sowohl f{\"u}r Forschungszwecke als auch zur Entwicklung neuartiger Trainingsger{\"a}te verwendet werden kann.}, language = {de} } @inproceedings{KolditzAlbinAlbrachtetal.2016, author = {Kolditz, Melanie and Albin, Thivaharan and Albracht, Kirsten and Br{\"u}ggemann, Gert-Peter and Abel, Dirk}, title = {Isokinematic leg extension training with an industrial robot}, series = {6th IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob) June 26-29, 2016. UTown, Singapore}, booktitle = {6th IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob) June 26-29, 2016. UTown, Singapore}, doi = {10.1109/BIOROB.2016.7523750}, pages = {950 -- 955}, year = {2016}, language = {de} } @article{KolditzAlbinAbeletal.2016, author = {Kolditz, Melanie and Albin, Thivaharan and Abel, Dirk and Fasse, Alessandro and Br{\"u}ggemann, Gert-Peter and Albracht, Kirsten}, title = {Evaluation of foot position and orientation as manipulated variables to control external knee adduction moments in leg extension training}, series = {Computer methods and programs in biomedicine}, volume = {171}, journal = {Computer methods and programs in biomedicine}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0169-2607}, doi = {10.1016/j.cmpb.2016.09.005}, pages = {81 -- 86}, year = {2016}, abstract = {Background and Objective Effective leg extension training at a leg press requires high forces, which need to be controlled to avoid training-induced damage. In order to avoid high external knee adduction moments, which are one reason for unphysiological loadings on knee joint structures, both training movements and the whole reaction force vector need to be observed. In this study, the applicability of lateral and medial changes in foot orientation and position as possible manipulated variables to control external knee adduction moments is investigated. As secondary parameters both the medio-lateral position of the center of pressure and the frontal-plane orientation of the reaction force vector are analyzed. Methods Knee adduction moments are estimated using a dynamic model of the musculoskeletal system together with the measured reaction force vector and the motion of the subject by solving the inverse kinematic and dynamic problem. Six different foot conditions with varying positions and orientations of the foot in a static leg press are evaluated and compared to a neutral foot position. Results Both lateral and medial wedges under the foot and medial and lateral shifts of the foot can influence external knee adduction moments in the presented study with six healthy subjects. Different effects are observed with the varying conditions: the pose of the leg is changed and the direction and center of pressure of the reaction force vector is influenced. Each effect results in a different direction or center of pressure of the reaction force vector. Conclusions The results allow the conclusion that foot position and orientation can be used as manipulated variables in a control loop to actively control knee adduction moments in leg extension training.}, language = {en} } @article{KohlerKirschnerHermannsStaatetal.2018, author = {Kohler, Annette and Kirschner-Hermanns, Ruth and Staat, Manfred and Brehmer, Bernhard}, title = {Pathogenese, funktionelle und anatomische Aspekte der weiblichen Belastungsinkontinenz}, series = {Aktuelle Urologie}, volume = {49}, journal = {Aktuelle Urologie}, number = {1}, publisher = {Thieme}, address = {Stuttgart}, issn = {1438-8820}, doi = {10.1055/s-0043-120616}, pages = {47 -- 51}, year = {2018}, abstract = {Der vorliegende Artikel fokussiert sich auf die weibliche Belastungsinkontinenz als Insuffizienz der Speicherfunktion der Blase, auch wenn im klinischen Alltag die Harninkontinenz der Frau h{\"a}ufig verschiedene Ursachen hat und insbesondere eine Belastungsinkontinenz im Alter und bei neurologischer Komorbidit{\"a}t nur selten isoliert vorkommt. Das kleine Becken der Frau ist sowohl als Funktions- als auch als strukturelle Einheit zu betrachten. Dabei unterliegen bei der Frau Blase, Harnr{\"o}hre, Geb{\"a}rmutter und Enddarm sowie die muskul{\"a}ren und ligament{\"o}sen Strukturen des kleinen Beckens durch Fertilit{\"a}tsphase, m{\"o}gliche Schwangerschaften, Geburten und Menopausen-Phase, {\"u}ber das „normale Altern" hinaus, gravierenden Ver{\"a}nderungen. This article focuses on female stress incontinence in the form of pelvic floor dysfunction and urethral sphincter deficiency, although isolated stress incontinence accounts for less than half of all incontinence cases. Especially in women of old age and those with neurological comorbidities, the causes of incontinence are mostly multifactorial. Also it has to be considered that the female bladder, urethra, uterus and rectum as well as the muscular and ligamentous structures of the female pelvis minor are affected by phases of fertility, possible pregnancies, births and menopause in addition to the normal ageing process.}, language = {de} } @article{KodomskoiKotliarSchroederetal.2019, author = {Kodomskoi, Leonid and Kotliar, Konstantin and Schr{\"o}der, Andreas and Weiss, Michael and Hille, Konrad}, title = {Suture-Probe Canaloplasty as an Alternative to Canaloplasty using the iTrack™ Microcatheter}, series = {Journal of Glaucoma}, journal = {Journal of Glaucoma}, number = {Epub ahead of print}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {1057-0829}, doi = {10.1097/IJG.0000000000001321}, year = {2019}, language = {en} } @article{KnoxBruggemannGossmannetal.2020, author = {Knox, Ronald and Bruggemann, Andrea and Gossmann, Matthias and Thomas, Ulrich and Horv{\´a}th, Andr{\´a}s and Dragicevic, Elena and Stoelzle-Feix, Sonja and Fertig, Niels and Jung, Alexander and Raman, Aravind Hariharan and Staat, Manfred and Linder, Peter}, title = {Combining physiological relevance and throughput for in vitro cardiac contractility measurement}, series = {Biophysical Journal}, volume = {118}, journal = {Biophysical Journal}, number = {Issue 3, Supplement 1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0006-3495}, doi = {10.1016/j.bpj.2019.11.3104}, pages = {570a}, year = {2020}, abstract = {Despite increasing acceptance of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in safety pharmacology, controversy remains about the physiological relevance of existing in vitro models for their mechanical testing. We hypothesize that existing signs of immaturity of the cell models result from an improper mechanical environment. We cultured hiPSC-CMs in a 96-well format on hyperelastic silicone membranes imitating their native mechanical environment, resulting in physiological responses to compound stimuli.We validated cell responses on the FLEXcyte 96, with a set of reference compounds covering a broad range of cellular targets, including ion channel modulators, adrenergic receptor modulators and kinase inhibitors. Acute (10 - 30 min) and chronic (up to 7 days) effects were investigated. Furthermore, the measurements were complemented with electromechanical models based on electrophysiological recordings of the used cell types.hiPSC-CMs were cultured on freely-swinging, ultra-thin and hyperelastic silicone membranes. The weight of the cell culture medium deflects the membranes downwards. Rhythmic contraction of the hiPSC-CMs resulted in dynamic deflection changes which were quantified by capacitive distance sensing. The cells were cultured for 7 days prior to compound addition. Acute measurements were conducted 10-30 minutes after compound addition in standard culture medium. For chronic treatment, compound-containing medium was replaced daily for up to 7 days. Electrophysiological properties of the employed cell types were recorded by automated patch-clamp (Patchliner) and the results were integrated into the electromechanical model of the system.Calcium channel agonist S Bay K8644 and beta-adrenergic stimulator isoproterenol induced significant positive inotropic responses without additional external stimulation. Kinase inhibitors displayed cardiotoxic effects on a functional level at low concentrations. The system-integrated analysis detected alterations in beating shape as well as frequency and arrhythmic events and we provide a quantitative measure of these.}, language = {en} } @incollection{KnottSofroniaGerressenetal.2014, author = {Knott, Thomas C. and Sofronia, Raluca E. and Gerressen, Marcus and Law, Yuen and Davidescu, Arjana and Savii, George G. and Gatzweiler, Karl-Heinz and Staat, Manfred and Kuhlen, Torsten W.}, title = {Preliminary bone sawing model for a virtual reality-based training simulator of bilateral sagittal split osteotomy}, series = {Biomedical simulation : 6th International Symposium, ISBMS 2014, Strasbourg, France, October 16-17, 2014 : proceedings (Lecture notes in computer science : vol. 8789)}, booktitle = {Biomedical simulation : 6th International Symposium, ISBMS 2014, Strasbourg, France, October 16-17, 2014 : proceedings (Lecture notes in computer science : vol. 8789)}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-12057-7 (Online)}, doi = {10.1007/978-3-319-12057-7_1}, pages = {1 -- 10}, year = {2014}, abstract = {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.}, language = {en} } @article{KezerashviliDachwald2021, author = {Kezerashvili, Roman Ya and Dachwald, Bernd}, title = {Preface: Solar sailing: Concepts, technology, and missions II}, series = {Advances in Space Research}, volume = {67}, journal = {Advances in Space Research}, number = {9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2021.01.037}, pages = {2559 -- 2560}, year = {2021}, language = {en} } @article{KeutmannStaatLaack2018, author = {Keutmann, Sabine and Staat, Manfred and Laack, Walter van}, title = {Untersuchung der thermischen Auswirkung von therapeutischem Ultraschall}, volume = {7}, number = {10}, publisher = {Deutscher {\"A}rzte-Verl.}, address = {K{\"o}ln}, issn = {2193-5793}, pages = {518 -- 522}, year = {2018}, abstract = {Zusammenfassung: In der Orthop{\"a}die z{\"a}hlt der therapeutische Ultraschall als Mittel zur Pr{\"a}vention und Therapiebegleitung. Er hat mechanische, thermische und physiko-chemische Auswirkungen auf den menschlichen K{\"o}rper. Um mehr Erkenntnisse {\"u}ber die thermischen Auswirkungen zu erlangen, wurden Versuche an einem Hydrogel-Phantom und an Probanden durchgef{\"u}hrt. Dabei entstand eine signifikante Erw{\"a}rmung des Gewebes, welche beim Probandenversuch an der Oberfl{\"a}che und beim Hydrogelversuch in der Tiefe gemessen wurde. Summary: In orthopaedics, therapeutic ultrasound is a tool of prevention and therapy support. It has mechanical, thermal and physico-chemical effects on the human body. Tests with a hydrogel phantom and with human probands have been performed in order to obtain more knowledge about their thermal effects. Both tests measured temperature increases in cell tissue, on the surface with the human proband test and in depth with the hydrogel phantom test.}, language = {de} } @article{KetelhutKolditzGoelletal.2019, author = {Ketelhut, Maike and Kolditz, Melanie and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Admittance control of an industrial robot during resistance training}, series = {IFAC-PapersOnLine}, volume = {52}, journal = {IFAC-PapersOnLine}, number = {19}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2019.12.102}, pages = {223 -- 228}, year = {2019}, abstract = {Neuromuscular strength training of the leg extensor muscles plays an important role in the rehabilitation and prevention of age and wealth related diseases. In this paper, we focus on the design and implementation of a Cartesian admittance control scheme for isotonic training, i.e. leg extension and flexion against a predefined weight. For preliminary testing and validation of the designed algorithm an experimental research and development platform consisting of an industrial robot and a force plate mounted at its end-effector has been used. Linear, diagonal and arbitrary two-dimensional motion trajectories with different weights for the leg extension and flexion part are applied. The proposed algorithm is easily adaptable to trajectories consisting of arbitrary six-dimensional poses and allows the implementation of individualized trajectories.}, language = {en} } @article{KetelhutGoellBraunsteinetal.2018, author = {Ketelhut, Maike and G{\"o}ll, Fabian and Braunstein, Bj{\"o}rn and Albracht, Kirsten and Abel, Dirk}, title = {Comparison of different training algorithms for the leg extension training with an industrial robot}, series = {Current Directions in Biomedical Engineering}, volume = {4}, journal = {Current Directions in Biomedical Engineering}, number = {1}, publisher = {De Gruyter}, address = {Berlin}, issn = {2364-5504}, doi = {10.1515/cdbme-2018-0005}, pages = {17 -- 20}, year = {2018}, abstract = {In the past, different training scenarios have been developed and implemented on robotic research platforms, but no systematic analysis and comparison have been done so far. This paper deals with the comparison of an isokinematic (motion with constant velocity) and an isotonic (motion against constant weight) training algorithm. Both algorithms are designed for a robotic research platform consisting of a 3D force plate and a high payload industrial robot, which allows leg extension training with arbitrary six-dimensional motion trajectories. In the isokinematic as well as the isotonic training algorithm, individual paths are defined i n C artesian s pace by sufficient s upport p oses. I n t he i sotonic t raining s cenario, the trajectory is adapted to the measured force as the robot should only move along the trajectory as long as the force applied by the user exceeds a minimum threshold. In the isotonic training scenario however, the robot's acceleration is a function of the force applied by the user. To validate these findings, a simulative experiment with a simple linear trajectory is performed. For this purpose, the same force path is applied in both training scenarios. The results illustrate that the algorithms differ in the force dependent trajectory adaption.}, language = {en} } @inproceedings{KetelhutGoellBraunsteinetal.2019, author = {Ketelhut, Maike and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Iterative learning control of an industrial robot for neuromuscular training}, series = {2019 IEEE Conference on Control Technology and Applications}, booktitle = {2019 IEEE Conference on Control Technology and Applications}, publisher = {IEEE}, address = {New York}, isbn = {978-1-7281-2767-5 (ePub)}, doi = {10.1109/CCTA.2019.8920659}, pages = {7 Seiten}, year = {2019}, abstract = {Effective training requires high muscle forces potentially leading to training-induced injuries. Thus, continuous monitoring and controlling of the loadings applied to the musculoskeletal system along the motion trajectory is required. In this paper, a norm-optimal iterative learning control algorithm for the robot-assisted training is developed. The algorithm aims at minimizing the external knee joint moment, which is commonly used to quantify the loading of the medial compartment. To estimate the external knee joint moment, a musculoskeletal lower extremity model is implemented in OpenSim and coupled with a model of an industrial robot and a force plate mounted at its end-effector. The algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee. The results show that the algorithm is able to minimize the external knee joint moment in all three cases and converges after less than seven iterations.}, language = {en} } @article{KetelhutBrueggeGoelletal.2020, author = {Ketelhut, Maike and Br{\"u}gge, G. M. and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Adaptive iterative learning control of an industrial robot during neuromuscular training}, series = {IFAC PapersOnLine}, volume = {53}, journal = {IFAC PapersOnLine}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2020.12.741}, pages = {16468 -- 16475}, year = {2020}, abstract = {To prevent the reduction of muscle mass and loss of strength coming along with the human aging process, regular training with e.g. a leg press is suitable. However, the risk of training-induced injuries requires the continuous monitoring and controlling of the forces applied to the musculoskeletal system as well as the velocity along the motion trajectory and the range of motion. In this paper, an adaptive norm-optimal iterative learning control algorithm to minimize the knee joint loadings during the leg extension training with an industrial robot is proposed. The response of the algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee and compared to the results of a higher-order iterative learning control algorithm, a robust iterative learning control and a recently proposed conventional norm-optimal iterative learning control algorithm. Although significant improvements in performance are made compared to the conventional norm-optimal iterative learning control algorithm with a small learning factor, for the developed approach as well as the robust iterative learning control algorithm small steady state errors occur.}, language = {en} } @article{KaulKoshkaryevArtmannetal.2008, author = {Kaul, D. K. and Koshkaryev, A. and Artmann, Gerhard and Barshtein, G. and Yedgar, S.}, title = {Additive effect of red blood cell rigidity and adherence to endothelial cells in inducing vascular resistance}, series = {American Journal of Physiology : Heart and Circulation Physiology . 295 (2008), H. 4}, volume = {295}, journal = {American Journal of Physiology : Heart and Circulation Physiology . 295 (2008), H. 4}, number = {4}, issn = {1522-1539}, pages = {H1788 -- H1793}, year = {2008}, language = {en} } @article{KaramanidisAlbrachtBraunsteinetal.2011, author = {Karamanidis, Kiros and Albracht, Kirsten and Braunstein, Bjoern and Catala, Maria Moreno and Goldmann, Jan-Peter and Br{\"u}ggemann, Gert-Peter}, title = {Lower leg musculoskeletal geometry and sprint performance}, series = {Gait and Posture}, volume = {34}, journal = {Gait and Posture}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0966-6362}, doi = {10.1016/j.gaitpost.2011.03.009}, pages = {138 -- 141}, year = {2011}, abstract = {The purpose of this study was to investigate whether sprint performance is related to lower leg musculoskeletal geometry within a homogeneous group of highly trained 100-m sprinters. Using a cluster analysis, eighteen male sprinters were divided into two groups based on their personal best (fast: N = 11, 10.30 ± 0.07 s; slow: N = 7, 10.70 ± 0.08 s). Calf muscular fascicle arrangement and Achilles tendon moment arms (calculated by the gradient of tendon excursion versus ankle joint angle) were analyzed for each athlete using ultrasonography. Achilles tendon moment arm, foot and ankle skeletal geometry, fascicle arrangement as well as the ratio of fascicle length to Achilles tendon moment arm showed no significant (p > 0.05) correlation with sprint performance, nor were there any differences in the analyzed musculoskeletal parameters between the fast and slow sprinter group. Our findings provide evidence that differences in sprint ability in world-class athletes are not a result of differences in the geometrical design of the lower leg even when considering both skeletal and muscular components.}, language = {en} } @article{KappmeyerKotliarLanzl2009, author = {Kappmeyer, K. and Kotliar, Konstantin and Lanzl, I. M.}, title = {Spielen von Blasinstrumenten und Augeninnendruck}, series = {Zeitschrift f{\"u}r praktische Augenheilkunde \& augen{\"a}rztliche Fortbildung : ZPA}, volume = {Bd. 30}, journal = {Zeitschrift f{\"u}r praktische Augenheilkunde \& augen{\"a}rztliche Fortbildung : ZPA}, issn = {1436-0322}, pages = {169 -- 171}, year = {2009}, language = {de} } @inproceedings{KahmannUschokWegmannetal.2018, author = {Kahmann, Stephanie Lucina and Uschok, Stephan and Wegmann, Kilian and M{\"u}ller, Lars-P. and Staat, Manfred}, title = {Biomechanical multibody model with refined kinematics of the elbow}, series = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, booktitle = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, pages = {11 Seiten}, year = {2018}, abstract = {The overall objective of this study is to develop a new external fixator, which closely maps the native kinematics of the elbow to decrease the joint force resulting in reduced rehabilitation time and pain. An experimental setup was designed to determine the native kinematics of the elbow during flexion of cadaveric arms. As a preliminary study, data from literature was used to modify a published biomechanical model for the calculation of the joint and muscle forces. They were compared to the original model and the effect of the kinematic refinement was evaluated. Furthermore, the obtained muscle forces were determined in order to apply them in the experimental setup. The joint forces in the modified model differed slightly from the forces in the original model. The muscle force curves changed particularly for small flexion angles but their magnitude for larger angles was consistent.}, language = {en} } @inproceedings{KahmannHacklWegmannetal.2016, author = {Kahmann, Stephanie and Hackl, Michael and Wegmann, Kilian and M{\"u}ller, Lars-Peter and Staat, Manfred}, title = {Impact of a proximal radial shortening osteotomy on the distribution of forces and the stability of the elbow}, series = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, booktitle = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, editor = {Erni, Daniel}, publisher = {Universit{\"a}t Duisburg-Essen}, address = {Duisburg}, organization = {MedTech Symposium}, doi = {10.17185/duepublico/40821}, pages = {7 -- 8}, year = {2016}, abstract = {The human arm consists of the humerus (upper arm), the medial ulna and the lateral radius (forearm). The joint between the humerus and the ulna is called humeroulnar joint and the joint between the humerus and the radius is called humeroradial joint. Lateral and medial collateral ligaments stabilize the elbow. Statistically, 2.5 out of 10,000 people suffer from radial head fractures [1]. In these fractures the cartilage is often affected. Caused by the injured cartilage, degenerative diseases like posttraumatic arthrosis may occur. The resulting pain and reduced range of motion have an impact on the patient's quality of life. Until now, there has not been a treatment which allows typical loads in daily life activities and offers good long-term results. A new surgical approach was developed with the motivation to reduce the progress of the posttraumatic arthrosis. Here, the radius is shortened by 3 mm in the proximal part [2]. By this means, the load of the radius is intended to be reduced due to a load shift to the ulna. Since the radius is the most important stabilizer of the elbow it has to be confirmed that the stability is not affected. In the first test (Fig. 1 left), pressure distributions within the humeroulnar and humeroradial joints a native and a shortened radius were measured using resistive pressure sensors (I5076 and I5027, Tekscan, USA). The humerus was loaded axially in a tension testing machine (Z010, Zwick Roell, Germany) in 50 N steps up to 400 N. From the humerus the load is transmitted through both the radius and the ulna into the hand which is fixed on the ground. In the second test (Fig. 1 right), the joint stability was investigated using a digital image correlation system to measure the displacement of the ulna. Here, the humerus is fixed with a desired flexion angle and the unconstrained forearm lies on the ground. A rope connects the load actuator with a hook fixed in the ulna. A guide roller is used so that the rope pulls the ulna horizontally when a tensile load is applied. This creates a moment about the elbow joint with a maximum value of 7.5 Nm. Measurements were performed with varying flexion angles (0°, 30°, 60°, 90°, 120°). For both tests and each measurement, seven specimens were used. Student's t-test was employed to determine whether the mean values of the measurements in native specimen and operated specimens differ significantly.}, 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} } @inproceedings{JungStaatMueller2016, author = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram}, title = {Effect of wind on flight style optimisation in ski jumping}, series = {15th International Symposium on Computer Simulation in Biomechanics ; July 9th-11th 2015, Edinburgh, UK}, booktitle = {15th International Symposium on Computer Simulation in Biomechanics ; July 9th-11th 2015, Edinburgh, UK}, publisher = {The University of Edinburgh ; Loughborough University}, address = {Edinburgh}, pages = {53 -- 54}, year = {2016}, language = {en} } @article{JungStaatMueller2018, author = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram}, title = {Corrigendum to "Flight style optimization in ski jumping on normal, large, and ski flying hills" [J. Biomech 47 (2014) 716-722]}, series = {Journals of Biomechanics}, journal = {Journals of Biomechanics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2018.02.001}, pages = {313}, year = {2018}, language = {en} } @inproceedings{JungStaat2016, author = {Jung, Alexander and Staat, Manfred}, title = {Computing olympic gold: Ski jumping as an example}, series = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, booktitle = {1st YRA MedTech Symposium 2016 : April 8th / 2016 / University of Duisburg-Essen}, editor = {Erni, Daniel}, publisher = {Universit{\"a}t Duisburg-Essen}, address = {Duisburg}, organization = {MedTech Symposium}, isbn = {978-3-940402-06-6}, doi = {10.17185/duepublico/40821}, pages = {54 -- 55}, year = {2016}, language = {en} }