TY - JOUR A1 - Waldvogel, Janice A1 - Ritzmann, Ramona A1 - Freyler, Kathrin A1 - Helm, Michael A1 - Monti, Elena A1 - Albracht, Kirsten A1 - Stäudle, Benjamin A1 - Gollhofer, Albert A1 - Narici, Marco T1 - The Anticipation of Gravity in Human Ballistic Movement JF - Frontiers in Physiology N2 - Stretch-shortening type actions are characterized by lengthening of the pre-activated muscle-tendon unit (MTU) in the eccentric phase immediately followed by muscle shortening. Under 1 g, pre-activity before and muscle activity after ground contact, scale muscle stiffness, which is crucial for the recoil properties of the MTU in the subsequent push-off. This study aimed to examine the neuro-mechanical coupling of the stretch-shortening cycle in response to gravity levels ranging from 0.1 to 2 g. During parabolic flights, 17 subjects performed drop jumps while electromyography (EMG) of the lower limb muscles was combined with ultrasound images of the gastrocnemius medialis, 2D kinematics and kinetics to depict changes in energy management and performance. Neuro-mechanical coupling in 1 g was characterized by high magnitudes of pre-activity and eccentric muscle activity allowing an isometric muscle behavior during ground contact. EMG during pre-activity and the concentric phase systematically increased from 0.1 to 1 g. Below 1 g the EMG in the eccentric phase was diminished, leading to muscle lengthening and reduced MTU stretches. Kinetic energy at take-off and performance were decreased compared to 1 g. Above 1 g, reduced EMG in the eccentric phase was accompanied by large MTU and muscle stretch, increased joint flexion amplitudes, energy loss and reduced performance. The energy outcome function established by linear mixed model reveals that the central nervous system regulates the extensor muscles phase- and load-specifically. In conclusion, neuro-mechanical coupling appears to be optimized in 1 g. Below 1 g, the energy outcome is compromised by reduced muscle stiffness. Above 1 g, loading progressively induces muscle lengthening, thus facilitating energy dissipation. Y1 - 2021 U6 - http://dx.doi.org/10.3389/fphys.2021.614060 SN - 1664-042X PB - Frontiers CY - Lausanne ER - TY - JOUR A1 - Waldvogel, Janice A1 - Freyler, Kathrin A1 - Helm, Michael A1 - Monti, Elena A1 - Stäudle, Benjamin A1 - Gollhofer, Albert A1 - Narici, Marco V. A1 - Ritzmann, Ramona A1 - Albracht, Kirsten T1 - Changes in gravity affect neuromuscular control, biomechanics, and muscle-tendon mechanics in energy storage and dissipation tasks JF - Journal of Applied Physiology N2 - This study evaluates neuromechanical control and muscle-tendon interaction during energy storage and dissipation tasks in hypergravity. During parabolic flights, while 17 subjects performed drop jumps (DJs) and drop landings (DLs), electromyography (EMG) of the lower limb muscles was combined with in vivo fascicle dynamics of the gastrocnemius medialis, two-dimensional (2D) kinematics, and kinetics to measure and analyze changes in energy management. Comparisons were made between movement modalities executed in hypergravity (1.8 G) and gravity on ground (1 G). In 1.8 G, ankle dorsiflexion, knee joint flexion, and vertical center of mass (COM) displacement are lower in DJs than in DLs; within each movement modality, joint flexion amplitudes and COM displacement demonstrate higher values in 1.8 G than in 1 G. Concomitantly, negative peak ankle joint power, vertical ground reaction forces, and leg stiffness are similar between both movement modalities (1.8 G). In DJs, EMG activity in 1.8 G is lower during the COM deceleration phase than in 1 G, thus impairing quasi-isometric fascicle behavior. In DLs, EMG activity before and during the COM deceleration phase is higher, and fascicles are stretched less in 1.8 G than in 1 G. Compared with the situation in 1 G, highly task-specific neuromuscular activity is diminished in 1.8 G, resulting in fascicle lengthening in both movement modalities. Specifically, in DJs, a high magnitude of neuromuscular activity is impaired, resulting in altered energy storage. In contrast, in DLs, linear stiffening of the system due to higher neuromuscular activity combined with lower fascicle stretch enhances the buffering function of the tendon, and thus the capacity to safely dissipate energy. KW - electromyography KW - locomotion KW - overload KW - stretch-shortening cycle KW - ultrasound Y1 - 2023 U6 - http://dx.doi.org/10.1152/japplphysiol.00279.2022 SN - 1522-1601 (Onlineausgabe) SN - 8750-7587 (Druckausgabe) VL - 134 IS - 1 SP - 190 EP - 202 PB - American Physiological Society CY - Bethesda, Md. ER - TY - CHAP A1 - Waldmann, Christoph A1 - Vera, Jean-Pierre de A1 - Dachwald, Bernd A1 - Strasdeit, Henry A1 - Sohl, Frank A1 - Hanff, Hendrik A1 - Kowalski, Julia A1 - Heinen, Dirk A1 - Macht, Sabine A1 - Bestmann, Ulf A1 - Meckel, Sebastian A1 - Hildebrandt, Marc A1 - Funke, Oliver A1 - Gehrt, Jan-Jöran T1 - Search for life in ice-covered oceans and lakes beyond Earth T2 - 2018 IEEE/OES Autonomous Underwater Vehicle Workshop, Proceedings November 2018, Article number 8729761 N2 - The quest for life on other planets is closely connected with the search for water in liquid state. Recent discoveries of deep oceans on icy moons like Europa and Enceladus have spurred an intensive discussion about how these waters can be accessed. The challenge of this endeavor lies in the unforeseeable requirements on instrumental characteristics both with respect to the scientific and technical methods. The TRIPLE/nanoAUV initiative is aiming at developing a mission concept for exploring exo-oceans and demonstrating the achievements in an earth-analogue context, exploring the ocean under the ice shield of Antarctica and lakes like Dome-C on the Antarctic continent. KW - Planetary exploration KW - Jupiter KW - ice moons KW - underwater vehicle KW - Antarctica Y1 - 2018 U6 - http://dx.doi.org/10.1109/AUV.2018.8729761 ER - TY - JOUR A1 - Vu, Duc-Khoi A1 - Staat, Manfred T1 - An algorithm for shakedown analysis of structure with temperature dependent yield stress N2 - This work is an attempt to answer the question: How to use convex programming in shakedown analysis of structures made of materials with temperature-dependent properties. Based on recently established shakedown theorems and formulations, a dual relationship between upper and lower bounds of the shakedown limit load is found, an algorithmfor shakedown analysis is proposed. While the original problem is neither convex nor concave, the algorithm presented here has the advantage of employing convex programming tools. KW - Einspielen KW - Temperaturabhängigkeit KW - Fließgrenze KW - Shakedown KW - shakedown analysis KW - yield stress Y1 - 2004 ER - TY - JOUR A1 - Vu, Duc Khoi A1 - Staat, Manfred A1 - Tran, Ich Thinh T1 - Analysis of pressure equipment by application of the primal-dual theory of shakedown JF - Communications in Numerical Methods in Engineering. 23 (2007), H. 3 Y1 - 2007 SN - 1069-8299 SP - 213 EP - 225 ER - TY - JOUR A1 - Vu, Duc Khoi A1 - Staat, Manfred T1 - Shakedown analysis of structures made of materials with temperature-dependent yield stress JF - International Journal of Solids and Structures. 44 (2007), H. 13 Y1 - 2007 SN - 0020-7683 SP - 4524 EP - 4540 ER - TY - CHAP A1 - Voronkova, Eva B. A1 - Bauer, Svetlana M. A1 - Kotliar, Konstantin T1 - Computer simulation of the cornea-scleral shell as applied to pressure-volume relationship in the human eye T2 - 2014 International Conference on Computer Technologies in Physical and Engineering Applications : ICCTPEA 2014 : proceedings : June 30 2014-July 4 2014, St. Petersburg Y1 - 2014 SN - 978-1-4799-5315-8 SP - 204 EP - 205 ER - TY - JOUR A1 - Vant, Christianne A1 - Staat, Manfred A1 - Baroud, Gamal T1 - Percutaneous Vertebroplasty: A Review of Two Intraoperative Complications JF - Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) Y1 - 2008 SN - 978-3-540-75408-4 SP - 527 EP - 539 PB - Springer CY - Berlin ER - TY - JOUR A1 - Uysal, Karya A1 - Firat, Ipek Serat A1 - Creutz, Till A1 - Aydin, Inci Cansu A1 - Artmann, Gerhard A1 - Teusch, Nicole A1 - Temiz Artmann, Aysegül T1 - A novel in vitro wound healing assay using free-standing, ultra-thin PDMS membranes JF - membranes N2 - Advances in polymer science have significantly increased polymer applications in life sciences. We report the use of free-standing, ultra-thin polydimethylsiloxane (PDMS) membranes, called CellDrum, as cell culture substrates for an in vitro wound model. Dermal fibroblast monolayers from 28- and 88-year-old donors were cultured on CellDrums. By using stainless steel balls, circular cell-free areas were created in the cell layer (wounding). Sinusoidal strain of 1 Hz, 5% strain, was applied to membranes for 30 min in 4 sessions. The gap circumference and closure rate of un-stretched samples (controls) and stretched samples were monitored over 4 days to investigate the effects of donor age and mechanical strain on wound closure. A significant decrease in gap circumference and an increase in gap closure rate were observed in trained samples from younger donors and control samples from older donors. In contrast, a significant decrease in gap closure rate and an increase in wound circumference were observed in the trained samples from older donors. Through these results, we propose the model of a cell monolayer on stretchable CellDrums as a practical tool for wound healing research. The combination of biomechanical cell loading in conjunction with analyses such as gene/protein expression seems promising beyond the scope published here. Y1 - 2022 U6 - http://dx.doi.org/10.3390/membranes13010022 N1 - This article belongs to the Special Issue "Latest Scientific Discoveries in Polymer Membranes" VL - 2023 IS - 13(1) PB - MDPI CY - Basel ER - TY - JOUR A1 - Uysal, Karya A1 - Creutz, Till A1 - Firat, Ipek Seda A1 - Artmann, Gerhard A1 - Teusch, Nicole A1 - Temiz Artmann, Aysegül T1 - Bio-functionalized ultra-thin, large-area and waterproof silicone membranes for biomechanical cellular loading and compliance experiments JF - Polymers N2 - Biocompatibility, flexibility and durability make polydimethylsiloxane (PDMS) membranes top candidates in biomedical applications. CellDrum technology uses large area, <10 µm thin membranes as mechanical stress sensors of thin cell layers. For this to be successful, the properties (thickness, temperature, dust, wrinkles, etc.) must be precisely controlled. The following parameters of membrane fabrication by means of the Floating-on-Water (FoW) method were investigated: (1) PDMS volume, (2) ambient temperature, (3) membrane deflection and (4) membrane mechanical compliance. Significant differences were found between all PDMS volumes and thicknesses tested (p < 0.01). They also differed from the calculated values. At room temperatures between 22 and 26 °C, significant differences in average thickness values were found, as well as a continuous decrease in thicknesses within a 4 °C temperature elevation. No correlation was found between the membrane thickness groups (between 3–4 µm) in terms of deflection and compliance. We successfully present a fabrication method for thin bio-functionalized membranes in conjunction with a four-step quality management system. The results highlight the importance of tight regulation of production parameters through quality control. The use of membranes described here could also become the basis for material testing on thin, viscous layers such as polymers, dyes and adhesives, which goes far beyond biological applications. Y1 - 2022 SN - 2073-4360 VL - 14 IS - 11 SP - 2213 PB - MDPI CY - Basel ER - TY - JOUR A1 - Ullrich, Sebastian A1 - Grottke, Oliver A1 - Rossaint, Rolf A1 - Staat, Manfred A1 - Deserno, Thomas M. A1 - Kuhlen, Torsten T1 - Virtual Needle Simulation with Haptics for Regional Anaesthesia Y1 - 2010 N1 - IEEE Virtual Reality 2010, Workshop on Medical Virtual Environments, Waltham, MA, USA, March 21, 2010 SP - 1 EP - 3 ER - TY - JOUR A1 - Turlybekuly, Amanzhol A1 - Pogrebnjak, Alexander A1 - Sukhodub, L. F. A1 - Sukhodub, Liudmyla B. A1 - Kistaubayeva, A. S. A1 - Savitskaya, Irina A1 - Shokatayeva, D. H. A1 - Bondar, Oleksandr V. A1 - Shaimardanov, Z. K. A1 - Plotnikov, Sergey V. A1 - Shaimardanova, B. H. A1 - Digel, Ilya T1 - Synthesis, characterization, in vitro biocompatibility and antibacterial properties study of nanocomposite materials based on hydroxyapatite-biphasic ZnO micro- and nanoparticles embedded in Alginate matrix JF - Materials Science and Engineering C Y1 - 2019 U6 - http://dx.doi.org/10.1016/j.msec.2019.109965 VL - 104 IS - Article number 109965 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Turaliyeva, M. A1 - Yeshibaev, A. A1 - Saparbekova, A. A1 - Akynova, L. A1 - Abildayeva, R. A1 - Sadenova, M. A1 - Sartayeva, K. A1 - Schieffer, Andre A1 - Digel, Ilya T1 - Species composition and injuriousness of stranger xylophilous fauna affecting indigenous urban dendroflora of Central Asia JF - Asian journal of microbiology, biotechnology & environmental sciences : AJMBES N2 - At the present time, one of the most serious environmental problems of Central Asia and South Kazakhstan is the ongoing large-scale deterioration of principal urban tree populations. Several major centers of massive spread of invasive plant pests have been found in urban dendroflora of this region. The degree of damage of seven most wide-spread aboriginal tree species was found to range from 21.4±1.1 to 85.4±1.8%. In particular, the integrity of the native communities of sycamore (Platanus spp.), willow (Salix spp.), poplar (Populus spp.) and elm (Ulmus spp.) is highly endangered. Our taxonomic analysis of the most dangerous tree pests of the region has revealed them as neobiontic xylophilous insects such as Cossus cossus L. (Order: Lepidoptera L.) Monochamus urussovi Fisch., Monochamus sutor L., Acanthocinus aedelis L. and Ñetonia aureate L. (Order: Coleoptera L.). We relate the origin of this threatening trend with the import of industrial wood in the mid 90’s of the last century that was associated with high degree of the constructional work in the region. Because of the absence of efficient natural predators of the pest species, the application of microbiological methods of the pest control and limitation is suggested. Y1 - 2016 SN - 0972-3005 VL - 18 IS - 2 SP - 359 EP - 366 PB - EM International ER - TY - JOUR A1 - Turaliyeva, M. A1 - Yeshibaev, A. A1 - Digel, Ilya A1 - Elibayeva, G. A1 - Sydykova, A. A1 - Uspabayeva, A. A1 - Dosybayeva, G. A1 - Zhylysbayeva, A. A1 - Lakhanova, K. T1 - Molecular-genetic identification of emerged novel invasive pathogens of Asiatic Elm Ulmus pumila L JF - Life science journal N2 - The dwarf elm Ulmus pumila L. (Ulmaceae) is one of indigenous species of flora in Kazakhstan and forms a basis of dendroflora in virtually all settlements of the region. In the past decade, multiple outbreaks of previously unknown diseases of the small-leaved elm have been registered. In our study, by the molecular-genetic analysis it was found that the pathogens responsible for the outbreaks are microfungi belonging to the genus Fusarium – F. solani and F. oxysporum. The nucleotide sequences (ITS regions) isolated from the diseased trees showed very high similarity with the GenBank control numbers EU625403.1 and FJ478128.1 (100.0 and 99.0 % respectively). Oncoming research will focus on the search of natural microbial antagonists of the discovered phytopathogens. Y1 - 2014 U6 - http://dx.doi.org/10.7537/marslsj1105s14.33 SN - 1097-8135 VL - 11 IS - Spec. iss. 5s SP - 171 EP - 175 PB - Marsland Press CY - New York ER - TY - JOUR A1 - Trzewik, Jürgen A1 - Temiz Artmann, Aysegül A1 - Linder, Peter A1 - Demirci, T. A1 - Digel, Ilya A1 - Artmann, Gerhard T1 - Evaluation of lateral mechanical tension in thin-film tissue constructs JF - Annals of Biomedical Engineering. 32 (2004), H. 9 Y1 - 2004 SN - 1573-9686 SP - 1243 EP - 1251 ER - TY - THES A1 - Trzewik, Jürgen T1 - Experimental analysis of biaxial mechanical tension in cell monolayers and cultured three-dimensional tissues: the celldrum technology Y1 - 2007 N1 - Zugl.: Ilmenau, Techn. Univ., Diss., 2007 PB - Univeristätsverlg Ilmenau CY - Ilmenau ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred A1 - Kreißig, R. T1 - Calculation of load carrying capacity of shell structures with elasto-plastic material by direct methods N2 - Proceedings of the International Conference on Material Theory and Nonlinear Dynamics. MatDyn. Hanoi, Vietnam, Sept. 24-26, 2007, 8 p. In this paper, a method is introduced to determine the limit load of general shells using the finite element method. The method is based on an upper bound limit and shakedown analysis with elastic-perfectly plastic material model. A non-linear constrained optimisation problem is solved by using Newton’s method in conjunction with a penalty method and the Lagrangean dual method. Numerical investigation of a pipe bend subjected to bending moments proves the effectiveness of the algorithm. KW - Finite-Elemente-Methode Y1 - 2007 ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Staat, Manfred A1 - Kreißig, R. T1 - Finite element shakedown and limit reliability analysis of thin shells N2 - A procedure for the evaluation of the failure probability of elastic-plastic thin shell structures is presented. The procedure involves a deterministic limit and shakedown analysis for each probabilistic iteration which is based on the kinematical approach and the use the exact Ilyushin yield surface. Based on a direct definition of the limit state function, the non-linear problems may be efficiently solved by using the First and Second Order Reliabiblity Methods (Form/SORM). This direct approach reduces considerably the necessary knowledge of uncertain technological input data, computing costs and the numerical error. In: Computational plasticity / ed. by Eugenio Onate. Dordrecht: Springer 2007. VII, 265 S. (Computational Methods in Applied Sciences ; 7) (COMPLAS IX. Part 1 . International Center for Numerical Methods in Engineering (CIMNE)). ISBN 978-1-402-06576-7 S. 186-189 KW - Finite-Elemente-Methode KW - Limit analysis KW - shakedown analysis KW - Exact Ilyushin yield surface KW - Random variable KW - First Order Reliabiblity Method Y1 - 2007 ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - Shakedown analysis of two dimensional structures by an edge-based smoothed finite element method Y1 - 2010 N1 - ECCM 2010, IV European Conference on Computational Mechanics, Paris, France, May 16-21, 2010. SP - 1 EP - 7 ER - TY - JOUR A1 - Tran, Thanh Ngoc A1 - Staat, Manfred T1 - An Edge-Based Smoothed Finite Element Method for Primal-Dual Shakedown Analysis of Structures Under Uncertainties JF - Limit State of Materials and Structures : Direct Methods 2. Saxcé, Géry de (Hrsg.) Y1 - 2013 SN - 978-94-007-5424-9 SP - 89 EP - 102 PB - Springer CY - Dordrecht ER -