@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{NguyenXuanRabczukNguyenThoietal.2011, author = {Nguyen-Xuan, H. and Rabczuk, T. and Nguyen-Thoi, T. and Tran, Thanh Ngoc and Nguyen-Thanh, N.}, title = {Computation of limit and shakedown loads using a node-based smoothed finite element method}, series = {International Journal for Numerical Methods in Engineering}, volume = {90}, journal = {International Journal for Numerical Methods in Engineering}, number = {3}, publisher = {Wiley}, address = {Weinheim}, issn = {1097-0207}, doi = {10.1002/nme.3317}, pages = {287 -- 310}, year = {2011}, abstract = {This paper presents a novel numerical procedure for computing limit and shakedown loads of structures using a node-based smoothed FEM in combination with a primal-dual algorithm. An associated primal-dual form based on the von Mises yield criterion is adopted. The primal-dual algorithm together with a Newton-like iteration are then used to solve this associated primal-dual form to determine simultaneously both approximate upper and quasi-lower bounds of the plastic collapse limit and the shakedown limit. The present formulation uses only linear approximations and its implementation into finite element programs is quite simple. Several numerical examples are given to show the reliability, accuracy, and generality of the present formulation compared with other available methods.}, language = {en} } @article{StaatTrenzLohmannetal.2012, author = {Staat, Manfred and Trenz, Eva and Lohmann, Philipp and Frotscher, Ralf and Klinge, Uwe and Tabaza, Ruth and Kirschner-Hermanns, Ruth}, title = {New measurements to compare soft tissue anchoring systems in pelvic floor surgery}, series = {Journal of Biomedical Materials Research Part B: Applied Biomaterials}, volume = {100B}, journal = {Journal of Biomedical Materials Research Part B: Applied Biomaterials}, number = {4}, publisher = {Wiley}, address = {Hoboken, NJ}, issn = {1552-4981}, doi = {10.1002/jbm.b.32654}, pages = {924 -- 933}, year = {2012}, abstract = {Suburethral slings as well as different meshes are widely used treating stress urinary incontinence and prolaps in women. With the development of MiniSlings and special meshes using less alloplastic material anchorage systems become more important to keep devices in place and to put some tension especially on the MiniSlings. To date, there are many different systems of MiniSlings of different companies on the market which differ in the structure of the used meshes and anchors. A new objective measurement method to compare different properties of MiniSling systems (mesh and anchor) is presented in this article. Ballistic gelatine acts as soft tissue surrogate. Significant differences in parameters like pull-out strength of anchors or shrinkage of meshes under loading conditions have been determined. The form and size of the anchors as well as the structural stability of the meshes are decisive for a proper integration. The tested anchorings sytems showed markedly different mechanical function at their respective load bearing capacity. As the stable fixation of the device in tissue is a prerequisite for a permanet reinforcement, the proposed test system permits further optimisation of anchor and mesh devices to improve the success of the surgical treatment}, language = {en} } @article{BassamHeschelerTemizArtmannetal.2012, author = {Bassam, Rasha and Hescheler, J{\"u}rgen and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard and Digel, Ilya}, title = {Effects of spermine NONOate and ATP on the thermal stability of hemoglobin}, series = {BMC Biophysics}, volume = {5}, journal = {BMC Biophysics}, publisher = {BioMed Central}, address = {London}, issn = {2046-1682}, doi = {10.1186/2046-1682-5-16}, pages = {Art. 16}, year = {2012}, abstract = {Background Minor changes in protein structure induced by small organic and inorganic molecules can result in significant metabolic effects. The effects can be even more profound if the molecular players are chemically active and present in the cell in considerable amounts. The aim of our study was to investigate effects of a nitric oxide donor (spermine NONOate), ATP and sodium/potassium environment on the dynamics of thermal unfolding of human hemoglobin (Hb). The effect of these molecules was examined by means of circular dichroism spectrometry (CD) in the temperature range between 25°C and 70°C. The alpha-helical content of buffered hemoglobin samples (0.1 mg/ml) was estimated via ellipticity change measurements at a heating rate of 1°C/min. Results Major results were: 1) spermine NONOate persistently decreased the hemoglobin unfolding temperature T u irrespectively of the Na + /K + environment, 2) ATP instead increased the unfolding temperature by 3°C in both sodium-based and potassium-based buffers and 3) mutual effects of ATP and NO were strongly influenced by particular buffer ionic compositions. Moreover, the presence of potassium facilitated a partial unfolding of alpha-helical structures even at room temperature. Conclusion The obtained data might shed more light on molecular mechanisms and biophysics involved in the regulation of protein activity by small solutes in the cell.}, language = {en} } @article{NomdedeuWillenSchiefferetal.2012, author = {Nomdedeu, Mar Monsonis and Willen, Christine and Schieffer, Andre and Arndt, Hartmut}, title = {Temperature-dependent ranges of coexistence in a model of a two-prey-one-predator microbial food web}, series = {Marine Biology}, volume = {159}, journal = {Marine Biology}, number = {11}, publisher = {Springer}, address = {Berlin}, issn = {1432-1793}, doi = {10.1007/s00227-012-1966-x}, pages = {2423 -- 2430}, year = {2012}, abstract = {The objective of our study was to analyze the effects of temperature on the population dynamics of a three-species food web consisting of two prey bacteria (Pedobacter sp. and Acinetobacter johnsonii) and a protozoan predator (Tetrahymena pyriformis) as model organisms. We assessed the effects of temperature on the growth rates of all three species with the objective of developing a model with four differential equations based on the experimental data. The following hypotheses were tested at a theoretical level: Firstly, temperature changes can affect the dynamic behavior of a system by temperature-dependent parameters and interactions and secondly, food web response to temperature cannot be derived from the single species temperature response. The main outcome of the study is that temperature changes affect the parameter range where coexistence is possible within all three species. This has significant consequences on our ideas regarding the evaluation of effects of global warming.}, language = {en} } @article{HasanKeilStaatetal.2012, author = {Hasan, Istabrak and Keil, Ludger and Staat, Manfred and Wahl, Gerhard and Bourauel, Christoph}, title = {Determination of the frictional coefficient of the implant-antler interface : experimental approach}, series = {Biomedical Engineering / Biomedizinische Technik}, volume = {57}, journal = {Biomedical Engineering / Biomedizinische Technik}, number = {5}, publisher = {De Gruyter}, address = {Berlin}, issn = {1862-278X}, pages = {359 -- 363}, year = {2012}, abstract = {The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5-0.7 and 0.3-0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens.}, language = {en} } @article{StadlerGarveyBocahutetal.2012, author = {Stadler, Andreas M. and Garvey, G. J. and Bocahut, A. and Sacquin-Mora, S. and Digel, Ilya and Schneider, G. J. and Natali, F. and Artmann, Gerhard and Zaccai, G.}, title = {Thermal fluctuations of haemoglobin from different species : adaptation to temperature via conformational dynamics}, series = {Journal of the Royal Society Interface}, volume = {9}, journal = {Journal of the Royal Society Interface}, number = {76}, publisher = {The Royal Society}, address = {London}, issn = {1742-5689}, doi = {10.1098/rsif.2012.0364}, pages = {2845 -- 2855}, year = {2012}, abstract = {Thermodynamic stability, configurational motions and internal forces of haemoglobin (Hb) of three endotherms (platypus, Ornithorhynchus anatinus; domestic chicken, Gallus gallus domesticus and human, Homo sapiens) and an ectotherm (salt water crocodile, Crocodylus porosus) were investigated using circular dichroism, incoherent elastic neutron scattering and coarse-grained Brownian dynamics simulations. The experimental results from Hb solutions revealed a direct correlation between protein resilience, melting temperature and average body temperature of the different species on the 0.1 ns time scale. Molecular forces appeared to be adapted to permit conformational fluctuations with a root mean square displacement close to 1.2 {\AA} at the corresponding average body temperature of the endotherms. Strong forces within crocodile Hb maintain the amplitudes of motion within a narrow limit over the entire temperature range in which the animal lives. In fully hydrated powder samples of human and chicken, Hb mean square displacements and effective force constants on the 1 ns time scale showed no differences over the whole temperature range from 10 to 300 K, in contrast to the solution case. A complementary result of the study, therefore, is that one hydration layer is not sufficient to activate all conformational fluctuations of Hb in the pico- to nanosecond time scale which might be relevant for biological function. Coarse-grained Brownian dynamics simulations permitted to explore residue-specific effects. They indicated that temperature sensing of human and chicken Hb occurs mainly at residues lining internal cavities in the β-subunits.}, language = {en} } @article{StaatVu2012, author = {Staat, Manfred and Vu, Duc Khoi}, title = {Limit analysis of flaws in pressurized pipes and cylindrical vessels Part II: Circumferential defects}, series = {Engineering Fracture Mechanics ; 97(2013), H. 1}, volume = {97}, journal = {Engineering Fracture Mechanics ; 97(2013), H. 1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0013-7944}, doi = {10.1016/j.engfracmech.2012.05.017}, pages = {314 -- 333}, year = {2012}, abstract = {Upper and lower bound theorems of limit analyses have been presented in part I of the paper. Part II starts with the finite element discretization of these theorems and demonstrates how both can be combined in a primal-dual optimization problem. This recently proposed numerical method is used to guide the development of a new class of closed-form limit loads for circumferential defects, which show that only large defects contribute to plastic collapse with a rapid loss of strength with increasing crack sizes. The formulae are compared with primal-dual FEM limit analyses and with burst tests. Even closer predictions are obtained with iterative limit load solutions for the von Mises yield function and for the Tresca yield function. Pressure loading of the faces of interior cracks in thick pipes reduces the collapse load of circumferential defects more than for axial flaws. Axial defects have been treated in part I of the paper.}, 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{NovacekTranKlingeetal.2012, author = {Novacek, V. and Tran, Thanh Ngoc and Klinge, U. and Tolba, R. H. and Staat, Manfred and Bronson, D. G. and Miesse, A. M. and Whiffen, J. and Turquier, F.}, title = {Finite element modelling of stapled colorectal end-to-end anastomosis : Advantages of variable height stapler design}, series = {Journal of Biomechanics}, volume = {45}, journal = {Journal of Biomechanics}, number = {115}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380}, doi = {10.1016/j.jbiomech.2012.07.021}, pages = {2693 -- 2697}, year = {2012}, abstract = {The impact of surgical staplers on tissues has been studied mostly in an empirical manner. In this paper, finite element method was used to clarify the mechanics of tissue stapling and associated phenomena. Various stapling modalities and several designs of circular staplers were investigated to evaluate the impact of the device on tissues and mechanical performance of the end-to-end colorectal anastomosis. Numerical simulations demonstrated that a single row of staples is not adequate to resist leakage due to non-linear buckling and opening of the tissue layers between two adjacent staples. Compared to the single staple row configuration, significant increase in stress experienced by the tissue at the inner staple rows was observed in two and three rows designs. On the other hand, adding second and/or third staple row had no effect on strain in the tissue inside the staples. Variable height design with higher staples in outer rows significantly reduced the stresses and strains in outer rows when compared to the same configuration with flat cartridge.}, language = {en} } @article{NguyenDuongTranetal.2012, author = {Nguyen, Nhu Huynh and Duong, Minh Tuan and Tran, Thanh Ngoc and Pham, Phu Tinh and Grottke, O. and Tolba, R. and Staat, Manfred}, title = {Influence of a freeze-thaw cycle on the stress-stretch curves of tissues of porcine abdominal organs}, series = {Journal of Biomechanics}, volume = {45}, journal = {Journal of Biomechanics}, number = {14}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380}, doi = {10.1016/j.jbiomech.2012.07.008}, pages = {2382 -- 2386}, year = {2012}, abstract = {The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze-thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze-thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines.}, language = {en} } @article{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{Staat2012, author = {Staat, Manfred}, title = {Limit and shakedown analysis under uncertainty}, series = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, volume = {19}, journal = {Tap chi Khoa hoc \& ung dung - Dai hoc Ton Duc Thang}, pages = {45 -- 47}, year = {2012}, language = {en} } @article{MansurovDigelBiisenbaevetal.2012, author = {Mansurov, Z. and Digel, Ilya and Biisenbaev, M. and Savistkaya, I. and Kistaubaeva, A. and Akimbekov, Nuraly S. and Zhubanova, A.}, title = {Bio-composite material on the basis of carbonized rice husk in biomedicine and environmental applications}, series = {Eurasian Chemico-Technological Journal}, volume = {14}, journal = {Eurasian Chemico-Technological Journal}, number = {2}, publisher = {Institute of Combustion Problems}, address = {Almaty}, issn = {2522-4867}, doi = {10.18321/ectj105}, pages = {115 -- 131}, year = {2012}, 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} } @article{AkimbekovMansurovJandosovetal.2013, author = {Akimbekov, Nuraly S. and Mansurov, Zulkhair and Jandosov, J. and Digel, Ilya and Gossmann, Matthias and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l and Zhubanova, Azhar A.}, title = {Wound healing activity of carbonized rice husk}, publisher = {Trans Tech Publications, Switzerland}, address = {B{\"a}ch}, year = {2013}, abstract = {The carbonized rice husk (CRH) was evaluated for its wound healing activity in rats using excision models. In this study, the influences of CRH on wound healing in rat skin in vivo and cellular behavior of human dermal fibroblasts in vitro were investigated. The obtained results showed that the CRH treatment promoted wound epithelization in rats and exhibited moderate inhibition of cell proliferation in vitro. CRH with lanolin oil treated wounds were found to epithelize faster as compared to controls.}, subject = {Wundheilung}, language = {en} } @article{PhamStaat2013, author = {Pham, Phu Tinh and Staat, Manfred}, title = {An Upper Bound Algorithm for Limit and Shakedown Analysis of Bounded Linearly Kinematic Hardening Structures}, series = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)}, journal = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-94-007-5424-9}, pages = {71 -- 87}, year = {2013}, language = {en} } @article{TranStaat2013, author = {Tran, Thanh Ngoc and Staat, Manfred}, title = {An Edge-Based Smoothed Finite Element Method for Primal-Dual Shakedown Analysis of Structures Under Uncertainties}, series = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)}, journal = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-94-007-5424-9}, pages = {89 -- 102}, year = {2013}, 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{FeuchtSchoenbachLanzletal.2013, author = {Feucht, Nikolaus and Sch{\"o}nbach, Etienne Michael and Lanzl, Ines and Kotliar, Konstantin and Lohmann, Chris Patrick and Maier, Mathias}, title = {Changes in the foveal microstructure after intravitreal bevacizumab application in patients with retinal vascular disease}, series = {Clinical Ophthalmology}, volume = {7}, journal = {Clinical Ophthalmology}, publisher = {Dove Medical Press}, address = {Auckland, New Zealand}, issn = {1177-5483}, pages = {173 -- 178}, year = {2013}, language = {en} } @article{BassamDigelHescheleretal.2013, author = {Bassam, Rasha and Digel, Ilya and Hescheler, J{\"u}rgen and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard}, title = {Effects of spermine NONOate and ATP on protein aggregation: light scattering evidences}, series = {BMC Biophysics}, journal = {BMC Biophysics}, publisher = {BioMed Central}, address = {London}, isbn = {2046-1682}, url = {http://nbn-resolving.de/10.1186/2046-1682-6-1}, pages = {1 -- 14}, year = {2013}, language = {en} } @article{Staat2013, author = {Staat, Manfred}, title = {Limit and shakedown analysis under uncertainty}, series = {International journal of computational methods : IJCM}, journal = {International journal of computational methods : IJCM}, publisher = {World Scientific Publishing}, address = {Singapore}, issn = {0219-8762}, pages = {Publ. online}, year = {2013}, language = {en} } @article{JungStaatMueller2013, author = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram}, title = {Flight style optimization in ski jumping on normal, large, and ski flying hills}, series = {Journal of biomechanics}, volume = {Vol. 47}, journal = {Journal of biomechanics}, number = {Iss. 3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2380 (E-Journal); 0021-9290 (Print)}, pages = {716 -- 722}, year = {2013}, language = {en} } @article{MiciliValterOflazetal.2013, author = {Micili, Serap C. and Valter, Markus and Oflaz, Hakan and Ozogul, Candan and Linder, Peter and F{\"o}ckler, Nicole and Artmann, Gerhard and Digel, Ilya and Temiz Artmann, Ayseg{\"u}l}, title = {Optical coherence tomography : a potential tool to predict premature rupture of fetal membranes}, series = {Proceedings of the Institution of Mechanical Engineers. Part H : Journal of engineering in medicine}, volume = {Vol. 227}, journal = {Proceedings of the Institution of Mechanical Engineers. Part H : Journal of engineering in medicine}, number = {No. 4}, publisher = {Sage}, address = {London}, issn = {0046-2039 (Print) ; 2041-3033 (E-Journal)}, pages = {393 -- 401}, year = {2013}, 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{JiminezGermanBehbahaniMiettinenetal.2013, author = {Jiminez German, Salvador and Behbahani, Mehdi and Miettinen, Susanna and Grijpma, Dirk W. and Haimi, Suvi P.}, title = {Proliferation and differentiation of adipose stem cells towards smooth muscle cells on poly(trimethylene carbonate) membranes}, series = {Macromolecular symposia}, volume = {Vol. 334}, journal = {Macromolecular symposia}, number = {Iss. 1}, publisher = {Wiley}, address = {Weinheim}, issn = {0258-0322}, pages = {133 -- 142}, year = {2013}, language = {en} } @article{AndingTabazaStaatetal.2013, author = {Anding, Ralf and Tabaza, Ruth and Staat, Manfred and Trenz, Eva and Lohmann, Philipp and Klinge, Uwe and Kirschner-Hermanns, Ruth}, title = {Introducing a method of in vitro testing of different anchoring systems used for female incontinence and prolapse surgery}, series = {BioMed research international}, volume = {Vol. 2013}, journal = {BioMed research international}, issn = {1110-7251 (E-Journal); 2314-6141 (E-Journal); 1110-7243 (Print); 2314-6133 (Print)}, pages = {Article ID 401417}, year = {2013}, language = {en} } @article{AlbrachtArampatzis2013, author = {Albracht, Kirsten and Arampatzis, Adamantios}, title = {Exercise-induced changes in triceps surae tendon stiffness and muscle strength affect running economy in humans}, series = {European Journal of Applied Physiology}, volume = {113}, journal = {European Journal of Applied Physiology}, number = {6}, publisher = {Springer}, address = {Berlin}, issn = {1439-6327}, doi = {10.1007/s00421-012-2585-4}, pages = {1605 -- 1615}, year = {2013}, language = {en} } @article{DigelAkimbekovTuralievaetal.2013, author = {Digel, Ilya and Akimbekov, Nuraly S. and Turalieva, M. and Mansurov, Z. and Temiz Artmann, Ayseg{\"u}l and Eshibaev, A. and Zhubanova, A.}, title = {Usage of Carbonized Plant Wastes for Purification of Aqueous Solutions}, series = {Journal of Industrial Technology and Engineering}, volume = {2}, journal = {Journal of Industrial Technology and Engineering}, number = {07}, pages = {47 -- 54}, year = {2013}, language = {en} } @article{AkimbekovDigelZhubanova2013, author = {Akimbekov, Nuraly S. and Digel, Ilya and Zhubanova, A. A.}, title = {Investigation the Influence of Carbonized Material Based On Rice Husk on Viability and Migration of Fibroblasts in T3B3 Cell Culture}, series = {KazNU Bulletin. Biology series}, volume = {59}, journal = {KazNU Bulletin. Biology series}, number = {3/1}, issn = {1563-0218}, pages = {20 -- 23}, year = {2013}, language = {en} } @article{AkimbekovDigelTastambeketal.2013, author = {Akimbekov, Nuraly S. and Digel, Ilya and Tastambek, K. T. and Zhubanova, A. A.}, title = {Biocompatibility of carbonized rice husk with a rat heart cells line H9c2}, series = {Experimental Biology}, volume = {59}, journal = {Experimental Biology}, number = {3/1}, issn = {1563-0218}, pages = {23 -- 25}, year = {2013}, language = {en} } @article{AkimbekovDigelSavitkayaetal.2013, author = {Akimbekov, Nuraly S. and Digel, Ilya and Savitkaya, I.S. and Zhubanova, A.A. and Tastambek, K.T.}, title = {Investigations of LPS endotoxin elimination in the flowing column conditions with the sorbent on the basis of carbonized rice husk}, series = {KazNU Bulletin. Biology series}, volume = {57}, journal = {KazNU Bulletin. Biology series}, number = {1}, issn = {1563-0218}, pages = {124 -- 127}, year = {2013}, language = {en} } @article{ArinkinDigelPorstetal.2014, author = {Arinkin, Vladimir and Digel, Ilya and Porst, Dariusz and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard}, title = {Phenotyping date palm varieties via leaflet cross-sectional imaging and artificial neural network application}, series = {BMC bioinformatics}, volume = {15}, journal = {BMC bioinformatics}, number = {55}, issn = {1471-2105}, doi = {10.1186/1471-2105-15-55}, pages = {1 -- 8}, year = {2014}, abstract = {Background True date palms (Phoenix dactylifera L.) are impressive trees and have served as an indispensable source of food for mankind in tropical and subtropical countries for centuries. The aim of this study is to differentiate date palm tree varieties by analysing leaflet cross sections with technical/optical methods and artificial neural networks (ANN). Results Fluorescence microscopy images of leaflet cross sections have been taken from a set of five date palm tree cultivars (Hewlat al Jouf, Khlas, Nabot Soltan, Shishi, Um Raheem). After features extraction from images, the obtained data have been fed in a multilayer perceptron ANN with backpropagation learning algorithm. Conclusions Overall, an accurate result in prediction and differentiation of date palm tree cultivars was achieved with average prediction in tenfold cross-validation is 89.1\% and reached 100\% in one of the best ANN.}, language = {en} } @article{PhamStaat2014, author = {Pham, Phu Tinh and Staat, Manfred}, title = {FEM-based shakedown analysis of hardening structures}, series = {Asia Pacific journal on computational engineering}, journal = {Asia Pacific journal on computational engineering}, number = {1}, publisher = {SpringerOpen}, address = {Berlin}, issn = {2196-1166 (E-Journal)}, doi = {10.1186/2196-1166-1-4}, pages = {Article No. 4}, year = {2014}, abstract = {This paper develops a new finite element method (FEM)-based upper bound algorithm for limit and shakedown analysis of hardening structures by a direct plasticity method. The hardening model is a simple two-surface model of plasticity with a fixed bounding surface. The initial yield surface can translate inside the bounding surface, and it is bounded by one of the two equivalent conditions: (1) it always stays inside the bounding surface or (2) its centre cannot move outside the back-stress surface. The algorithm gives an effective tool to analyze the problems with a very high number of degree of freedom. Our numerical results are very close to the analytical solutions and numerical solutions in literature.}, language = {en} } @article{FuestKotliarWalteretal.2014, author = {Fuest, Matthias and Kotliar, Konstantin and Walter, Peter and Plange, Niklas}, title = {Monitoring intraocular pressure changes after intravitreal Ranibizumab injection using rebound tonometry}, series = {Ophthalmic and physiological optics}, volume = {34}, journal = {Ophthalmic and physiological optics}, number = {4}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1475-1313 (E-Journal); 0275-5408 (Print)}, doi = {10.1111/opo.12134}, pages = {438 -- 444}, year = {2014}, language = {en} } @article{TuraliyevaYeshibaevDigeletal.2014, author = {Turaliyeva, M. and Yeshibaev, A. and Digel, Ilya and Elibayeva, G. and Sydykova, A. and Uspabayeva, A. and Dosybayeva, G. and Zhylysbayeva, A. and Lakhanova, K.}, title = {Molecular-genetic identification of emerged novel invasive pathogens of Asiatic Elm Ulmus pumila L}, series = {Life science journal}, volume = {11}, journal = {Life science journal}, number = {Spec. iss. 5s}, publisher = {Marsland Press}, address = {New York}, issn = {1097-8135}, doi = {10.7537/marslsj1105s14.33}, pages = {171 -- 175}, year = {2014}, abstract = {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.}, language = {en} } @article{MansurovJandosovKerimkulovaetal.2014, author = {Mansurov, Z. A. and Jandosov, J. M. and Kerimkulova, A. R. and Azat, S. and Zhubanova, A. A. and Digel, Ilya and Savistkaya, I. S. and Akimbekov, Nuraly S. and Kistaubaeva, A. S.}, title = {Nanostructured carbon materials for biomedical use}, series = {Eurasian chemico-technological journal : quarterly journal of the International Higher Education Academy of Sciences}, volume = {15 (2013)}, journal = {Eurasian chemico-technological journal : quarterly journal of the International Higher Education Academy of Sciences}, number = {3}, publisher = {Institute of Combustion Problems}, address = {Almaty}, issn = {1562-3920}, doi = {10.18321/ectj224}, pages = {209 -- 217}, year = {2014}, abstract = {One of the priority trends of carbon nanotechnology is creation of nanocomposite systems. Such carbon nanostructured composites were produced using - raw materials based on the products of agricultural waste, such as grape stones, apricot stones, rice husk. These products have a - wide spectrum of application and can be obtained in large quantities. The Institute of Combustion Problems has carried out the work on synthesis of the nanostructured carbon sorbents for multiple applications including the field of biomedicine. The article presents the data on the synthesis and physico-chemical properties of carbonaceous sorbents using physicochemical methods of investigation: separation and purification of biomolecules; isolation of phytohormone - fusicoccin; adsorbent INGO-1 in the form of an adsorption column for blood detoxification, oral (entero) sorbent - INGO-2; the study of efferent and probiotic properties and sorption activity in regard to the lipopolysaccharide (LPS), new biocomposites - based on carbonized rice husk (CRH) and cellular microorganisms; the use of CRH in wound treatment. A new material for blood detoxication (INGO-1) has been obtained. Adsorption of p-cresyl sulfate and indoxyl sulfate has shown that active carbon adsorbent can remove clinically significant level of p-cresyl sulfate and indoxyl sulfate from human plasma. Enterosorbent INGO-2 possesses high adsorption activity in relation to Gram-negative bacteria and their endotoxins. INGO-2 slows down the growth of conditionally pathogenic microorganisms, without having a negative effect on bifido and lactobacteria. The use of enterosorbent INGO-2 for sorption therapy may provide a solution to a complex problem - detoxication of the digestive tract and normalization of the intestinal micro ecology. The immobilized probiotic called "Riso-lact" was registered at the Ministry of Health of the Republic of Kazakhstan as a biologically active food additive. The developed technology is patented and provides production of the medicine in the form of freeze-dried biomass immobilized in vials.}, language = {en} } @article{FrotscherStaat2014, author = {Frotscher, Ralf and Staat, Manfred}, title = {Stresses produced by different textile mesh implants in a tissue equivalent}, series = {BioNanoMaterials}, volume = {15}, journal = {BioNanoMaterials}, number = {1-2}, publisher = {De Gruyter}, address = {Berlin}, issn = {2191-4672 (E-Journal); 2193-066X (E-Journal); 0011-8656 (Print); 1616-0177 (Print); 2193-0651 (Print)}, doi = {10.1515/bnm-2014-0003}, pages = {25 -- 30}, year = {2014}, abstract = {Two single-incision mini-slings used for treating urinary incontinence in women are compared with respect to the stresses they produce in their surrounding tissue. In an earlier paper we experimentally observed that these implants produce considerably different stress distributions in a muscle tissue equivalent. Here we perform 2D finite element analyses to compare the shear stresses and normal stresses in the tissue equivalent for the two meshes and to investigate their failure behavior. The results clearly show that the Gynecare TVT fails for increasing loads in a zipper-like manner because it gradually debonds from the surrounding tissue. Contrary to that, the tissue at the ends of the DynaMesh-SIS direct may rupture but only at higher loads. The simulation results are in good agreement with the experimental observations thus the computational model helps to interpret the experimental results and provides a tool for qualitative evaluation of mesh implants.}, language = {en} } @article{StadlerGarveyEmbsetal.2014, author = {Stadler, Alexander Maximilian and Garvey, Christopher J. and Embs, Jan Peter and Koza, Michael Marek and Unruh, Tobias and Artmann, Gerhard and Zaccai, Guiseppe}, title = {Picosecond dynamics in haemoglobin from different species: A quasielastic neutron scattering study}, series = {Biochimica et biophysica acta (BBA): General Subjects}, volume = {1840}, journal = {Biochimica et biophysica acta (BBA): General Subjects}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-8006 (E-Journal); 0304-4165 (Print)}, doi = {10.1016/j.bbagen.2014.06.007}, pages = {2989 -- 2999}, year = {2014}, language = {en} } @article{DachwaldMikuckiTulaczyketal.2014, author = {Dachwald, Bernd and Mikucki, Jill and Tulaczyk, Slawek and Digel, Ilya and Espe, Clemens and Feldmann, Marco and Francke, Gero and Kowalski, Julia and Xu, Changsheng}, title = {IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems}, series = {Annals of Glaciology}, volume = {55}, journal = {Annals of Glaciology}, number = {65}, publisher = {Cambridge University Press}, address = {Cambridge}, issn = {1727-5644}, doi = {10.3189/2014AoG65A004}, pages = {14 -- 22}, year = {2014}, abstract = {There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample.}, language = {en} } @article{MartinGonzalezKotliarRiosMartinezetal.2014, author = {Martin-Gonzalez, Anabel and Kotliar, Konstantin and Rios-Martinez, Jorge and Lanzl, Ines and Navab, Nassir}, title = {Mediated-reality magnification for macular degeneration rehabilitation}, series = {Journal of Modern Optics}, volume = {61}, journal = {Journal of Modern Optics}, number = {17}, publisher = {Taylor \& Francis}, address = {London}, issn = {1362-3044}, doi = {10.1080/09500340.2014.936110}, pages = {1400 -- 1408}, year = {2014}, language = {en} } @article{AkimbekovDigelOHerasetal.2014, author = {Akimbekov, Nuraly S. and Digel, Ilya and O´Heras, C. and Tastambek, K.T. and Savitskaya, I.S. and Ualyeva, P.S. and Mansurov, Z.A. and Zhubanova, A.A.}, title = {Adsorption of bacterial lipopolysaccharides on carbonized rice husks obtained in the batch experiments}, series = {Experimental Biology}, volume = {60}, journal = {Experimental Biology}, number = {1/2}, publisher = {Al-Farabi Kazakh National University}, address = {Almaty}, issn = {1563-0218}, pages = {144 -- 148}, year = {2014}, abstract = {The scope of this study is the measurement of endotoxin adsorption rate for carbonized rice husk. It showed good adsorption properties for LPS. During the batch experiments, several techniques were used and optimized for improving the material's adsorption behavior. Also, with the results obtained it was possible to differentiate the materials according to their adsorption capacity and kinetic characteristics.}, language = {en} } @article{YangKriechbaumerAlbrachtetal.2014, author = {Yang, Peng-Fei and Kriechbaumer, Andreas and Albracht, Kirsten and Sanno, Maximilian and Ganse, Bergita and Koy, Timmo and Shang, Peng and br{\"u}ggemann, Gert-Peter and M{\"u}ller, Lars Peter and Rittweger, J{\"o}rn}, title = {A novel optical approach for assessing in vivo bone segment deformation and its application in muscle-bone relationship studies in humans}, series = {Journal of Orthopaedic Translation}, volume = {2}, journal = {Journal of Orthopaedic Translation}, number = {4}, publisher = {Elsevier}, address = {Singapore}, issn = {2214-0328}, doi = {10.1016/j.jot.2014.07.078}, pages = {238 -- 238}, year = {2014}, language = {en} } @article{SeifarthGossmannGrosseetal.2015, author = {Seifarth, Volker and Goßmann, Matthias and Grosse, J. O. and Becker, C. and Heschel, I. and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {Development of a Bioreactor to Culture Tissue Engineered Ureters Based on the Application of Tubular OPTIMAIX 3D Scaffolds}, series = {Urologia Internationalis}, volume = {2015}, journal = {Urologia Internationalis}, number = {95}, publisher = {Karger}, address = {Basel}, issn = {0042-1138}, doi = {10.1159/000368419}, pages = {106 -- 113}, year = {2015}, language = {en} } @article{CehreliAkpinarTemizArtmannetal.2015, author = {Cehreli, Ruksan and Akpinar, Hale and Temiz Artmann, Ayseg{\"u}l and Sagol, Ozgul}, title = {Effects of Glutamine and Omega-3 Fatty Acids on Erythrocyte Deformability and Oxidative Damage in Rat Model of Enterocolitis}, series = {Gastroenterology Research}, volume = {8}, journal = {Gastroenterology Research}, number = {5}, issn = {1918-2813}, doi = {10.14740/gr683w}, pages = {265 -- 273}, year = {2015}, language = {en} } @article{DuongNguyenStaat2015, author = {Duong, Minh Tuan and Nguyen, Nhu Huynh and Staat, Manfred}, title = {Physical response of hyperelastic models for composite materials and soft tissues}, series = {Asia pacific journal on computational engineering}, volume = {2}, journal = {Asia pacific journal on computational engineering}, number = {3 (December 2015)}, issn = {2196-1166}, doi = {10.1186/s40540-015-0015-x}, pages = {1 -- 18}, year = {2015}, 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} } @article{FrotscherKochStaat2015, author = {Frotscher, Ralf and Koch, Jan-Peter and Staat, Manfred}, title = {Computational investigation of drug action on human-induced stem cell derived cardiomyocytes}, series = {Journal of biomechanical engineering}, volume = {Vol. 137}, journal = {Journal of biomechanical engineering}, number = {iss. 7}, publisher = {ASME}, address = {New York}, issn = {1528-8951 (E-Journal); 0148-0731 (Print)}, doi = {10.1115/1.4030173}, pages = {071002-1 -- 071002-7}, year = {2015}, language = {en} } @article{DuongNguyenTranetal.2015, author = {Duong, Minh Tuan and Nguyen, Nhu Huynh and Tran, Thanh Ngoc and Tolba, R. H. and Staat, Manfred}, title = {Influence of refrigerated storage on tensile mechanical properties of porcine liver and spleen}, series = {International biomechanics}, volume = {Vol. 2}, journal = {International biomechanics}, number = {Iss. 1}, publisher = {Taylor \& Francis}, address = {London}, issn = {2333-5432}, doi = {10.1080/23335432.2015.1049295}, pages = {79 -- 88}, year = {2015}, language = {en} } @article{GrundmannDachwaldGrimmetal.2015, author = {Grundmann, Jan Thimo and Dachwald, Bernd and Grimm, Christian D. and Kahle, Ralph and Koch, Aaron Dexter and Krause, Christian and Lange, Caroline and Quantius, Dominik and Ulamec, Stephan}, title = {Spacecraft for Hypervelocity Impact Research - An Overview of Capabilities, Constraints and the Challenges of Getting There}, series = {Procedia Engineering}, volume = {Vol. 103}, journal = {Procedia Engineering}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1877-7058}, doi = {10.1016/j.proeng.2015.04.021}, pages = {151 -- 158}, year = {2015}, language = {en} } @article{YangKriechbaumerAlbrachtetal.2015, author = {Yang, Peng-Fei and Kriechbaumer, Andreas and Albracht, Kirsten and Sanno, Maximilian and Ganse, Bergita and Koy, Timmo and Shang, Peng and Br{\"u}ggemann, Gert-Peter and M{\"u}ller, Lars Peter and Rittweger, J{\"o}rn}, title = {On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo}, series = {Journal of Biomechanics}, volume = {48}, journal = {Journal of Biomechanics}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2014.12.031}, pages = {456 -- 464}, year = {2015}, language = {en} } @article{SeynnesBojsenMollerAlbrachtetal.2015, author = {Seynnes, O. R. and Bojsen-Moller, J. and Albracht, Kirsten and Arndt, A. and Cronin, N. J. and Finni, T. and Magnusson, S. P.}, title = {Ultrasound-based testing of tendon mechanical properties: a critical evaluation}, series = {Journal of Applied Physiology}, volume = {118}, journal = {Journal of Applied Physiology}, number = {2}, issn = {8750-7587}, doi = {10.1152/japplphysiol.00849.2014}, pages = {133 -- 141}, year = {2015}, language = {en} } @article{AkimbekovDigelO’Herasetal.2015, author = {Akimbekov, Nuraly S. and Digel, Ilya and O'Heras, C. and Tastambek, K.T. and Savitskaya, I.S. and Ualyeva, P.S. and Mansurov, Z.A. and Zhubanova, A.A.}, title = {Adsorption of bacterial lipopol ysaccharides on carbonized ri ce husks obtained in the batch experiments}, series = {KazNU Bulletin. Biology series}, volume = {60}, journal = {KazNU Bulletin. Biology series}, number = {No 1/2}, issn = {1563-0218}, pages = {144 -- 148}, year = {2015}, language = {en} } @article{GossmannFrotscherLinderetal.2016, author = {Goßmann, Matthias and Frotscher, Ralf and Linder, Peter and Bayer, Robin and Epple, U. and Staat, Manfred and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard}, title = {Mechano-pharmacological characterization of cardiomyocytes derived from human induced pluripotent stem cells}, series = {Cellular physiology and biochemistry}, volume = {38}, journal = {Cellular physiology and biochemistry}, number = {3}, publisher = {Karger}, address = {Basel}, issn = {1421-9778 (Online)}, doi = {10.1159/000443124}, pages = {1182 -- 1198}, year = {2016}, abstract = {Background/Aims: Common systems for the quantification of cellular contraction rely on animal-based models, complex experimental setups or indirect approaches. The herein presented CellDrum technology for testing mechanical tension of cellular monolayers and thin tissue constructs has the potential to scale-up mechanical testing towards medium-throughput analyses. Using hiPS-Cardiac Myocytes (hiPS-CMs) it represents a new perspective of drug testing and brings us closer to personalized drug medication. Methods: In the present study, monolayers of self-beating hiPS-CMs were grown on ultra-thin circular silicone membranes and deflect under the weight of the culture medium. Rhythmic contractions of the hiPS-CMs induced variations of the membrane deflection. The recorded contraction-relaxation-cycles were analyzed with respect to their amplitudes, durations, time integrals and frequencies. Besides unstimulated force and tensile stress, we investigated the effects of agonists and antagonists acting on Ca²⁺ channels (S-Bay K8644/verapamil) and Na⁺ channels (veratridine/lidocaine). Results: The measured data and simulations for pharmacologically unstimulated contraction resembled findings in native human heart tissue, while the pharmacological dose-response curves were highly accurate and consistent with reference data. Conclusion: We conclude that the combination of the CellDrum with hiPS-CMs offers a fast, facile and precise system for pharmacological, toxicological studies and offers new preclinical basic research potential.}, language = {en} } @article{FrotscherMuanghongDursunetal.2016, author = {Frotscher, Ralf and Muanghong, Danita and Dursun, G{\"o}zde and Goßmann, Matthias and Temiz Artmann, Ayseg{\"u}l and Staat, Manfred}, title = {Sample-specific adaption of an improved electro-mechanical model of in vitro cardiac tissue}, series = {Journal of Biomechanics}, volume = {49}, journal = {Journal of Biomechanics}, number = {12}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290 (Print)}, doi = {10.1016/j.jbiomech.2016.01.039}, pages = {2428 -- 2435}, year = {2016}, abstract = {We present an electromechanically coupled computational model for the investigation of a thin cardiac tissue construct consisting of human-induced pluripotent stem cell-derived atrial, ventricular and sinoatrial cardiomyocytes. The mechanical and electrophysiological parts of the finite element model, as well as their coupling are explained in detail. The model is implemented in the open source finite element code Code_Aster and is employed for the simulation of a thin circular membrane deflected by a monolayer of autonomously beating, circular, thin cardiac tissue. Two cardio-active drugs, S-Bay K8644 and veratridine, are applied in experiments and simulations and are investigated with respect to their chronotropic effects on the tissue. These results demonstrate the potential of coupled micro- and macroscopic electromechanical models of cardiac tissue to be adapted to experimental results at the cellular level. Further model improvements are discussed taking into account experimentally measurable quantities that can easily be extracted from the obtained experimental results. The goal is to estimate the potential to adapt the presented model to sample specific cell cultures.}, 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{HacklMuellerStaatetal.2016, author = {Hackl, Michael and M{\"u}ller, Lars-Peter and Staat, Manfred and Kahmann, Stephanie Lucina and Wegmann, Kilian}, title = {Proximal phalangeal neck fractures of the hand — a biomechanical comparison of three fixation techniques}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {148 -- 149}, year = {2016}, abstract = {Plate osteosynthesis of displaced proximal phalangeal neck fractures of the hand allows early mobilization due to a stable internal fixation. Nevertheless, joint stiffness—because of soft tissue irritation—represents a common complication leading to high complication rates. Del Pinal et al. recently reported promising clinical results for a new, minimally invasive fixation technique with a cannulated headless intramedullary compression screw. Hence, the aim of this study was to compare plate fixation of proximal phalangeal neck fractures to less two less invasive techniques: Crossed k-wire fixation and intramedullary screw fixation. We hypothesized that these fixation techniques provide inferior stability when compared to plate osteosynthesis.}, language = {en} } @article{HacklKahmannWegmannetal.2016, author = {Hackl, Michael and Kahmann, Stephanie Lucina and Wegmann, Kilian and Ries, Christian and Staat, Manfred and M{\"u}ller, Lars-Peter}, title = {Shortening osteotomy of the proximal radius — a treatment option for isolated osteoarthritis of the lateral column of the elbow joint?}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {128 -- 129}, year = {2016}, abstract = {Treatment of posttraumatic osteoarthritis of the radial column of the elbow joint remains a challenging yet common issue. While partial joint replacement leads to high revision rates, radial head excision has shown to severely increase joint instability. Shortening osteotomy of the radius could be an option to decrease the contact pressure of the radiohumeral joint and thereby pain levels without causing valgus instability. Hence, the aim of this biomechanical study was to evaluate the effects of radial shortening on axial load distribution and valgus stability of the elbow joint.}, language = {en} } @article{HacklLeschingerStaatetal.2016, author = {Hackl, Michael and Leschinger, T. and Staat, Manfred and M{\"u}ller, Lars-Peter and Wegmann, Kilian}, title = {Reconstruction of the interosseous membrane in the Essex Lopresti lesion — a biomechanical evaluation}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4080-7}, pages = {130 -- 131}, year = {2016}, abstract = {Surgical reconstruction of the interosseous membrane (IOM) could restore longitudinal forearm stability to avoid persisting disability due to capituloradial and ulnocarpal impingement in Essex Lopresti lesions. This biomechanical study aimed to assess longitudinal forearm stability of intact specimens, after sectioning of the IOM and after reconstruction with a TightRope construct using either a single or double bundle technique.}, language = {en} } @article{WegmannHacklStaatetal.2016, author = {Wegmann, Kilian and Hackl, Michael and Staat, Manfred and Mayer, Katharina and M{\"u}ller, Lars-Peter}, title = {Double plate osteosynthesis of proximal ulna fractures: biomechanical and clinical results}, series = {Knee surgery, sports traumatology, arthroscopy}, volume = {Volume 24}, journal = {Knee surgery, sports traumatology, arthroscopy}, number = {Supplement 1}, publisher = {Springer}, address = {Berlin}, issn = {0942-2056}, doi = {10.1007/s00167-016-4079-0}, pages = {58 -- 59}, year = {2016}, abstract = {While plate fixation of proximal ulna fractures might lead to superior clinical results compared to tension band wiring, regular plates represent an established risk factor for wound complications. The olecranon double plates (Medartis, Basel, CH) might decrease complications related to the osteosynthesis because of their low profile and better anatomical fit. This study aimed to evaluate the biomechanical performance and clinical results of the olecranon double plates.}, language = {en} } @article{PookhalilAmoabedinyTabeshetal.2016, author = {Pookhalil, Ali and Amoabediny, Ghassem and Tabesh, Hadi and Behbahani, Mehdi and Mottaghy, Khosrow}, title = {A new approach for semiempirical modeling of mechanical blood trauma}, series = {The international journal of artificial organs}, volume = {39}, journal = {The international journal of artificial organs}, number = {4}, publisher = {Sage}, address = {London}, issn = {1724-6040}, doi = {10.5301/ijao.5000474}, pages = {171 -- 177}, year = {2016}, abstract = {Purpose Two semi-empirical models were recently published, both making use of existing literature data, but each taking into account different physical phenomena that trigger hemolysis. In the first model, hemoglobin (Hb) release is described as a permeation procedure across the membrane, assuming a shear stress-dependent process (sublethal model). The second model only accounts for hemoglobin release that is caused by cell membrane breakdown, which occurs when red blood cells (RBC) undergo mechanically induced shearing for a period longer than the threshold time (nonuniform threshold model). In this paper, we introduce a model that considers the hemolysis generated by both these possible phenomena. Methods Since hemolysis can possibly be caused by permeation of hemoglobin through the RBC functional membrane as well as by release of hemoglobin from RBC membrane breakdown, our proposed model combines both these models. An experimental setup consisting of a Couette device was utilized for validation of our proposed model. Results A comparison is presented between the damage index (DI) predicted by the proposed model vs. the sublethal model vs. the nonthreshold model and experimental datasets. This comparison covers a wide range of shear stress for both human and porcine blood. An appropriate agreement between the measured DI and the DI predicted by the present model was obtained. Conclusions The semiempirical hemolysis model introduced in this paper aims for significantly enhanced conformity with experimental data. Two phenomenological outcomes become possible with the proposed approach: an estimation of the average time after which cell membrane breakdown occurs under the applied conditions, and a prediction of the ratio between the phenomena involved in hemolysis.}, language = {en} } @article{AlbannaConzenWeissetal.2016, author = {Albanna, W. and Conzen, C. and Weiss, M. and Clusmann, H. and Fuest, M. and Mueller, M. and Brockmann, M.A. and Vilser, W. and Schmidt-Trucks{\"a}ss, A. and Hoellig, A. and Seiz, M. and Thom{\´e}, C. and Kotliar, Konstantin and Schubert, G.A.}, title = {Retinal Vessel Analysis (RVA) in the context of subarachnoid hemorrhage: A proof of concept study}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {7}, publisher = {PLOS}, address = {San Francisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0158781}, pages = {13 Seiten}, year = {2016}, abstract = {Background Timely detection of impending delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is essential to improve outcome, but poses a diagnostic challenge. Retinal vessels as an embryological part of the intracranial vasculature are easily accessible for analysis and may hold the key to a new and non-invasive monitoring technique. This investigation aims to determine the feasibility of standardized retinal vessel analysis (RVA) in the context of SAH. Methods In a prospective pilot study, we performed RVA in six patients awake and cooperative with SAH in the acute phase (day 2-14) and eight patients at the time of follow-up (mean 4.6±1.7months after SAH), and included 33 age-matched healthy controls. Data was acquired using a manoeuvrable Dynamic Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and neurovascular coupling. Results Image quality was satisfactory in the majority of cases (93.3\%). In the acute phase after SAH, retinal arteries were significantly dilated when compared to the control group (124.2±4.3MU vs 110.9±11.4MU, p<0.01), a difference that persisted to a lesser extent in the later stage of the disease (122.7±17.2MU, p<0.05). Testing for neurovascular coupling showed a trend towards impaired primary vasodilation and secondary vasoconstriction (p = 0.08, p = 0.09 resp.) initially and partial recovery at the time of follow-up, indicating a relative improvement in a time-dependent fashion. Conclusion RVA is technically feasible in patients with SAH and can detect fluctuations in vessel diameter and autoregulation even in less severely affected patients. Preliminary data suggests potential for RVA as a new and non-invasive tool for advanced SAH monitoring, but clinical relevance and prognostic value will have to be determined in a larger cohort.}, language = {en} } @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{BelavyAlbrachtBruggemannetal.2016, author = {Belavy, Daniel L. and Albracht, Kirsten and Bruggemann, Gert-Peter and Vergroesen, Pieter-Paul A. and Dieen, Jaap H. van}, title = {Can exercise positively influence the intervertebral disc?}, series = {Sports Medicine}, volume = {46}, journal = {Sports Medicine}, number = {4}, publisher = {Springer}, address = {Berlin}, issn = {1179-2035}, doi = {10.1007/s40279-015-0444-2}, pages = {473 -- 485}, year = {2016}, abstract = {To better understand what kinds of sports and exercise could be beneficial for the intervertebral disc (IVD), we performed a review to synthesise the literature on IVD adaptation with loading and exercise. The state of the literature did not permit a systematic review; therefore, we performed a narrative review. The majority of the available data come from cell or whole-disc loading models and animal exercise models. However, some studies have examined the impact of specific sports on IVD degeneration in humans and acute exercise on disc size. Based on the data available in the literature, loading types that are likely beneficial to the IVD are dynamic, axial, at slow to moderate movement speeds, and of a magnitude experienced in walking and jogging. Static loading, torsional loading, flexion with compression, rapid loading, high-impact loading and explosive tasks are likely detrimental for the IVD. Reduced physical activity and disuse appear to be detrimental for the IVD. We also consider the impact of genetics and the likelihood of a 'critical period' for the effect of exercise in IVD development. The current review summarises the literature to increase awareness amongst exercise, rehabilitation and ergonomic professionals regarding IVD health and provides recommendations on future directions in research.}, language = {en} } @article{TuraliyevaYeshibaevSaparbekovaetal.2016, author = {Turaliyeva, M. and Yeshibaev, A. and Saparbekova, A. and Akynova, L. and Abildayeva, R. and Sadenova, M. and Sartayeva, K. and Schieffer, Andre and Digel, Ilya}, title = {Species composition and injuriousness of stranger xylophilous fauna affecting indigenous urban dendroflora of Central Asia}, series = {Asian journal of microbiology, biotechnology \& environmental sciences : AJMBES}, volume = {18}, journal = {Asian journal of microbiology, biotechnology \& environmental sciences : AJMBES}, number = {2}, publisher = {EM International}, issn = {0972-3005}, pages = {359 -- 366}, year = {2016}, abstract = {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 {\~N}etonia 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.}, language = {en} } @article{AimenovaDigelEshibaev2016, author = {Aimenova, Zh. E. and Digel, Ilya and Eshibaev, А. А.}, title = {Dynamics of accumulation of lagochirzin in Lagochilus setulosus phytomass during the growing season and also features of its cultivation in the conditions of a typical sierozem}, series = {KazNU Bulletin. Biology series}, volume = {69}, journal = {KazNU Bulletin. Biology series}, number = {4}, publisher = {Al-Farabi Kazakh National University}, address = {Almaty}, issn = {1563-0218}, pages = {4 -- 11}, year = {2016}, abstract = {L.setulosus is offered for creation of biopreparation «Setulin», possesing he- mostatic action, the basic reactant of biopreparation is diterpen - lagochirzin. Results under the maintenance and dynamics of diterpen lagochirzin accumula- tion in various parts of L.setulosus are presented: in roots, stalks, leaves, flowers and calyx lobes during the growing season, and also results on conditions of cultivation L.setulosus in the conditions of a typical sierozem are resulted. From the obtained data is visible, that the given species of a plant is endemic. It is established, that dynamics of accumulation of lagochirzin in phytomass accrues from the beginning to the middle of the growing season. The chemical analysis of L.setulosus on a localization of lagochirzin in various organs of a plant, has shown, that the greatest quantity of lagochirzin collects in calyx lobes of the plants. Also it is established, that L.setulosus can be cultivated in the conditions of the typical sierozem, a mineral food is necessary for the given species of plants of Lagochilus genus, except nitric fertilizers. Comparative studying of wild-growing and cultural forms of L.setulosus has shown, that in the cultivated phytomass of plants the maintenance of lagochirzin on 17-20 \% higher than in the wild-growing species.}, language = {en} } @article{PeloniCeriottiDachwald2016, author = {Peloni, Alessandro and Ceriotti, Matteo and Dachwald, Bernd}, title = {Solar-sail trajectory design for a multiple near-earth-asteroid rendezvous mission}, series = {Journal of Guidance, Control, and Dynamics}, volume = {39}, journal = {Journal of Guidance, Control, and Dynamics}, number = {12}, publisher = {AIAA}, address = {Reston, Va.}, issn = {0731-5090}, doi = {10.2514/1.G000470}, pages = {2712 -- 2724}, year = {2016}, abstract = {The scientific interest for near-Earth asteroids as well as the interest in potentially hazardous asteroids from the perspective of planetary defense led the space community to focus on near-Earth asteroid mission studies. A multiple near-Earth asteroid rendezvous mission with close-up observations of several objects can help to improve the characterization of these asteroids. This work explores the design of a solar-sail spacecraft for such a mission, focusing on the search of possible sequences of encounters and the trajectory optimization. This is done in two sequential steps: a sequence search by means of a simplified trajectory model and a set of heuristic rules based on astrodynamics, and a subsequent optimization phase. A shape-based approach for solar sailing has been developed and is used for the first phase. The effectiveness of the proposed approach is demonstrated through a fully optimized multiple near-Earth asteroid rendezvous mission. The results show that it is possible to visit five near-Earth asteroids within 10 years with near-term solar-sail technology.}, language = {en} } @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{NiedermeyerZhouDursunetal.2016, author = {Niedermeyer, Angela and Zhou, Bei and Dursun, G{\"o}zde and Temiz Artmann, Ayseg{\"u}l and Markert, Bernd}, title = {An examination of tissue engineered scaffolds in a bioreactor}, series = {Proceedings in Applied Mathematics and Mechanics PAMM}, volume = {16}, journal = {Proceedings in Applied Mathematics and Mechanics PAMM}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1617-7061}, doi = {10.1002/pamm.201610038}, pages = {99 -- 100}, year = {2016}, abstract = {Replacement tissues, designed to fill in articular cartilage defects, should exhibit the same properties as the native material. The aim of this study is to foster the understanding of, firstly, the mechanical behavior of the material itself and, secondly, the influence of cultivation parameters on cell seeded implants as well as on cell migration into acellular implants. In this study, acellular cartilage replacement material is theoretically, numerically and experimentally investigated regarding its viscoelastic properties, where a phenomenological model for practical applications is developed. Furthermore, remodeling and cell migration are investigated.}, language = {en} } @article{HacklAndermahrStaatetal.2017, author = {Hackl, M. and Andermahr, J. and Staat, Manfred and Bremer, I. and Borggrefe, J. and Prescher, A. and M{\"u}ller, L. P. and Wegmann, K.}, title = {Suture button reconstruction of the central band of the interosseous membrane in Essex-Lopresti lesions: a comparative biomechanical investigation}, series = {The Journal of Hand Surgery (European Volume)}, volume = {42}, journal = {The Journal of Hand Surgery (European Volume)}, number = {4}, publisher = {Sage}, address = {London}, issn = {2043-6289 (Online)}, doi = {10.1177/1753193416665943}, pages = {370 -- 376}, year = {2017}, language = {en} } @article{SavitskayaKistaubayevaDigeletal.2017, author = {Savitskaya, I. S. and Kistaubayeva, A. S. and Digel, Ilya and Shokatayeva, D. H.}, title = {Physicochemical and Antibacterial Properties of Composite Films Based on Bacterial Cellulose and Chitosan for Wound Dressing Materials}, series = {Eurasian Chemico-Technological Journal}, volume = {19}, journal = {Eurasian Chemico-Technological Journal}, number = {3}, issn = {2522-4867}, doi = {10.18321/ectj670}, pages = {255 -- 264}, year = {2017}, language = {en} } @article{HorbachDuongStaat2017, author = {Horbach, Andreas and Duong, Minh Tuan and Staat, Manfred}, title = {Modelling of compressible and orthotropic surgical mesh implants based on optical deformation measurement}, series = {Journal of the mechanical behavior of biomedical materials}, volume = {74}, journal = {Journal of the mechanical behavior of biomedical materials}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1751-6161}, doi = {10.1016/j.jmbbm.2017.06.012}, pages = {400 -- 410}, year = {2017}, language = {en} } @article{MichaelMayerWeberetal.2017, author = {Michael, Hackl and Mayer, Katharina and Weber, Mareike and Staat, Manfred and van Riet, Roger and Burkhart, Klau Josef and M{\"u}ller, Lars Peter and Wegmann, Kilian}, title = {Plate osteosynthesis of proximal ulna fractures : a biomechanical micromotion analysis}, series = {The journal of hand surgery}, volume = {42}, journal = {The journal of hand surgery}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0363-5023}, doi = {10.1016/j.jhsa.2017.05.014}, pages = {834.e1 -- 834.e7}, year = {2017}, language = {en} } @article{PeloniDachwaldCeriotti2017, author = {Peloni, Alessandro and Dachwald, Bernd and Ceriotti, Matteo}, title = {Multiple near-earth asteroid rendezvous mission: Solar-sailing options}, series = {Advances in Space Research}, journal = {Advances in Space Research}, number = {In Press, Corrected Proof}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2017.10.017}, year = {2017}, language = {en} } @article{TranMottaghyArltKoerferetal.2017, author = {Tran, Linda and Mottaghy, K. and Arlt-K{\"o}rfer, Sabine and Waluga, Christian and Behbahani, Mehdi}, title = {An experimental study of shear-dependent human platelet adhesion and underlying protein-binding mechanisms in a cylindrical Couette system}, series = {Biomedizinische Technik}, volume = {62}, journal = {Biomedizinische Technik}, number = {4}, publisher = {De Gruyter}, address = {Berlin}, issn = {0013-5585}, doi = {10.1515/bmt-2015-0034}, pages = {383 -- 392}, year = {2017}, language = {en} } @article{AlbannaLuekeSjapicetal.2017, author = {Albanna, Walid and Lueke, Jan Niklas and Sjapic, Volha and Kotliar, Konstantin and Hescheler, J{\"u}rgen and Clusmann, Hans and Sjapic, Sergej and Alpdogan, Serdan and Schneider, Toni and Schubert, Gerrit Alexander and Neumaier, Felix}, title = {Electroretinographic Assessment of Inner Retinal Signaling in the Isolated and Superfused Murine Retina}, series = {Current Eye Research}, journal = {Current Eye Research}, number = {Article in press}, publisher = {Taylor \& Francis}, address = {London}, issn = {1460-2202}, doi = {10.1080/02713683.2017.1339807}, pages = {1 -- 9}, year = {2017}, language = {en} } @article{SeifarthGrosseGrossmannetal.2017, author = {Seifarth, Volker and Grosse, Joachim O. and Grossmann, Matthias and Janke, Heinz Peter and Arndt, Patrick and Koch, Sabine and Epple, Matthias and Artmann, Gerhard and Temiz Artmann, Ayseg{\"u}l}, title = {Mechanical induction of bi-directional orientation of primary porcine bladder smooth muscle cells in tubular fibrin-poly(vinylidene fluoride) scaffolds for ureteral and urethral repair using cyclic and focal balloon catheter stimulation}, series = {Journal of Biomaterials Applications}, volume = {32}, journal = {Journal of Biomaterials Applications}, number = {3}, publisher = {Sage}, address = {London}, issn = {1530-8022}, doi = {10.1177/0885328217723178}, pages = {321 -- 330}, year = {2017}, 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{WerkhausenAlbrachtCroninetal.2017, author = {Werkhausen, Amelie and Albracht, Kirsten and Cronin, Neil J. and Meier, Rahel and Mojsen-Moeller, Jens and Seynnes, Olivier R.}, title = {Modulation of muscle-tendon interaction in the human triceps surae during an energy dissipation task}, series = {Journal of Experimental Biology}, volume = {220}, journal = {Journal of Experimental Biology}, number = {22}, issn = {0022-0949}, doi = {10.1242/jeb.164111}, pages = {4141 -- 4149}, year = {2017}, language = {en} } @article{MuellerJungAhammer2017, author = {M{\"u}ller, Wolfram and Jung, Alexander and Ahammer, Helmut}, title = {Advantages and problems of nonlinear methods applied to analyze physiological time signals: human balance control as an example}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, number = {Article number 2464}, publisher = {Springer Nature}, address = {Cham}, isbn = {2045-2322}, doi = {10.1038/s41598-017-02665-5}, pages = {1 -- 11}, year = {2017}, language = {en} } @article{ZangeSchopenAlbrachtetal.2017, author = {Zange, Jochen and Schopen, Kathrin and Albracht, Kirsten and Gerlach, Darius A. and Frings-Meuthen, Petra and Maffiuletti, Nicola A. and Bloch, Wilhelm and Rittweger, J{\"o}rn}, title = {Using the Hephaistos orthotic device to study countermeasure effectiveness of neuromuscular electrical stimulation and dietary lupin protein supplementation, a randomised controlled trial}, series = {Plos one}, volume = {12}, journal = {Plos one}, number = {2}, doi = {10.1371/journal.pone.0171562}, year = {2017}, language = {en} } @article{HacklWegmannKahmannetal.2017, author = {Hackl, Michael and Wegmann, Kilian and Kahmann, Stephanie Lucina and Heinze, Nicolai and Staat, Manfred and Neiss, Wolfram F. and Scaal, Martin and M{\"u}ller, Lars P.}, title = {Radial shortening osteotomy reduces radiocapitellar contact pressures while preserving valgus stability of the elbow}, series = {Knee Surgery, Sports Traumatology, Arthroscopy}, volume = {25}, journal = {Knee Surgery, Sports Traumatology, Arthroscopy}, number = {7}, publisher = {Springer}, address = {Berlin}, issn = {1433-7347}, doi = {10.1007/s00167-017-4468-z}, pages = {2280 -- 2288}, year = {2017}, language = {en} } @article{JungMuellerStaat2018, author = {Jung, Alexander and M{\"u}ller, Wolfram and Staat, Manfred}, title = {Wind and fairness in ski jumping: A computer modelling analysis}, series = {Journal of Biomechanics}, journal = {Journal of Biomechanics}, number = {75}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2018.05.001}, pages = {147 -- 153}, year = {2018}, abstract = {Wind is closely associated with the discussion of fairness in ski jumping. To counter-act its influence on the jump length, the International Ski Federation (FIS) has introduced a wind compensation approach. We applied three differently accurate computer models of the flight phase with wind (M1, M2, and M3) to study the jump length effects of various wind scenarios. The previously used model M1 is accurate for wind blowing in direction of the flight path, but inaccuracies are to be expected for wind directions deviating from the tangent to the flight path. M2 considers the change of airflow direction, but it does not consider the associated change in the angle of attack of the skis which additionally modifies drag and lift area time functions. M3 predicts the length effect for all wind directions within the plane of the flight trajectory without any mathematical simplification. Prediction errors of M3 are determined only by the quality of the input data: wind velocity, drag and lift area functions, take-off velocity, and weight. For comparing the three models, drag and lift area functions of an optimized reference jump were used. Results obtained with M2, which is much easier to handle than M3, did not deviate noticeably when compared to predictions of the reference model M3. Therefore, we suggest to use M2 in future applications. A comparison of M2 predictions with the FIS wind compensation system showed substantial discrepancies, for instance: in the first flight phase, tailwind can increase jump length, and headwind can decrease it; this is opposite of what had been anticipated before and is not considered in the current wind compensation system in ski jumping.}, 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} } @article{DigelWehlitzKayseretal.2018, author = {Digel, Ilya and Wehlitz, V. and Kayser, Peter and Figiel-Lange, A. and Bassam, R. and Rundstedt, F. von}, title = {Suspension depletion approach for exemption of infected Solanum jasminoides cells from pospiviroids}, series = {Plant Pathology}, volume = {67}, journal = {Plant Pathology}, number = {2}, publisher = {Wiley}, address = {Oxford}, issn = {1365-3059}, doi = {10.1111/ppa.12750}, pages = {358 -- 365}, year = {2018}, abstract = {Despite numerous studies, viroid elimination from infected plants remains a very challenging task. This study introduces for the first time a novel 'suspension depletion' approach for exemption of Solanum jasminoides plants from viroids. The proposed method implies initial establishment of suspension cultures of the infected plant cells. The suspended cells were then physically treated (mild thermotherapy, 33 °C), which presumably delayed the replication of the viroid. The viroid concentration in the treated biomass was monitored weekly using pospiviroid-specific PCR. After 10-12 weeks of continuous treatment, a sufficient decrease in viroid concentration was observed such that the infection became undetectable by PCR. The treated single cells then gave rise to microcolonies on a solid culture medium and the obtained viroid-negative clones were further promoted to regenerate into viroid-free plants. Three years of accumulated experimental data suggests feasibility, broad applicability, and good efficacy of the proposed approach.}, language = {en} } @article{ConzenAlbannaWeissetal.2018, author = {Conzen, Catharina and Albanna, Walid and Weiss, Miriam and K{\"u}rten, David and Vilser, Walthard and Kotliar, Konstantin and Z{\"a}ske, Charlotte and Clusmann, Hans and Schubert, Gerrit Alexander}, title = {Vasoconstriction and Impairment of Neurovascular Coupling after Subarachnoid Hemorrhage: a Descriptive Analysis of Retinal Changes}, series = {Translational Stroke Research}, journal = {Translational Stroke Research}, number = {9}, publisher = {Springer Nature}, address = {Cham}, issn = {1868-601X}, doi = {10.1007/s12975-017-0585-8}, pages = {284 -- 293}, year = {2018}, abstract = {Impaired cerebral autoregulation and neurovascular coupling (NVC) contribute to delayed cerebral ischemia after subarachnoid hemorrhage (SAH). Retinal vessel analysis (RVA) allows non-invasive assessment of vessel dimension and NVC hereby demonstrating a predictive value in the context of various neurovascular diseases. Using RVA as a translational approach, we aimed to assess the retinal vessels in patients with SAH. RVA was performed prospectively in 24 patients with acute SAH (group A: day 5-14), in 11 patients 3 months after ictus (group B: day 90 ± 35), and in 35 age-matched healthy controls (group C). Data was acquired using a Retinal Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and NVC using flicker-light excitation. Diameter of retinal vessels—central retinal arteriolar and venular equivalent—was significantly reduced in the acute phase (p < 0.001) with gradual improvement in group B (p < 0.05). Arterial NVC of group A was significantly impaired with diminished dilatation (p < 0.001) and reduced area under the curve (p < 0.01) when compared to group C. Group B showed persistent prolonged latency of arterial dilation (p < 0.05). Venous NVC was significantly delayed after SAH compared to group C (A p < 0.001; B p < 0.05). To our knowledge, this is the first clinical study to document retinal vasoconstriction and impairment of NVC in patients with SAH. Using non-invasive RVA as a translational approach, characteristic patterns of compromise were detected for the arterial and venous compartment of the neurovascular unit in a time-dependent fashion. Recruitment will continue to facilitate a correlation analysis with clinical course and outcome.}, language = {en} } @article{BhattaraiJabbariAndingetal.2018, author = {Bhattarai, Aroj and Jabbari, Medisa and Anding, Ralf and Staat, Manfred}, title = {Surgical treatment of vaginal vault prolapse using different prosthetic mesh implants: a finite element analysis}, series = {tm - Technisches Messen}, volume = {85}, journal = {tm - Technisches Messen}, number = {5}, publisher = {De Gruyter}, address = {Berlin}, issn = {2196-7113}, doi = {10.1515/teme-2017-0115}, pages = {331 -- 342}, year = {2018}, abstract = {Particularly multiparous elderly women may suffer from vaginal vault prolapse after hysterectomy due to weak support from lax apical ligaments. A decreased amount of estrogen and progesterone in older age is assumed to remodel the collagen thereby reducing tissue stiffness. Sacrocolpopexy is either performed as open or laparoscopic surgery using prosthetic mesh implants to substitute lax ligaments. Y-shaped mesh models (DynaMesh, Gynemesh, and Ultrapro) are implanted in a 3D female pelvic floor finite element model in the extraperitoneal space from the vaginal cuff to the first sacral (S1) bone below promontory. Numerical simulations are conducted during Valsalva maneuver with weakened tissues modeled by reduced tissue stiffness. Tissues are modeled as incompressible, isotropic hyperelastic materials whereas the meshes are modeled either as orthotropic linear elastic or as isotropic hyperlastic materials. The positions of the vaginal cuff and the bladder base are calculated from the pubococcygeal line for female pelvic floor at rest, for prolapse and after repair using the three meshes. Due to mesh mechanics and mesh pore deformation along the loaded direction, the DynaMesh with regular rectangular mesh pores is found to provide better mechanical support to the organs than the Gynemesh and the Ultrapro with irregular hexagonal mesh pores. Insbesondere {\"a}ltere, mehrgeb{\"a}hrende Frauen leiden h{\"a}ufiger an einem Scheidenvorfall nach einer Hysterektomie aufgrund der schwachen Unterst{\"u}tzung durch laxe apikale B{\"a}nder. Es wird angenommen, dass eine verringerte Menge an {\"O}strogen und Progesteron im h{\"o}heren Alter das Kollagen umformt, wodurch die Gewebesteifigkeit reduziert wird. Die Sakrokolpopexie ist eine offene oder laparoskopische Operation, die mit prothetischen Netzimplantaten durchgef{\"u}hrt wird, um laxe B{\"a}nder zu ersetzen. Y-f{\"o}rmige Netzmodelle (DynaMesh, Gynemesh und Ultrapro) werden in einem 3D-Modell des weiblichen Beckenbodens im extraperitonealen Raum vom Vaginalstumpf bis zum Promontorium implantiert. Numerische Simulationen werden w{\"a}hrend des Valsalva-Man{\"o}vers mit geschw{\"a}chtem Gewebe durchgef{\"u}hrt, das durch eine reduzierte Gewebesteifigkeit modelliert wird. Die Gewebe werden als inkompressible, isotrop hyperelastische Materialien modelliert, w{\"a}hrend die Netze entweder als orthotrope linear elastische oder als isotrope hyperlastische Materialien modelliert werden. Die Positionen des Vaginalstumpfs, der Blase und der Harnr{\"o}hrenachse werden anhand der Pubococcygeallinie aus der Ruhelage, f{\"u}r den Prolaps und nach der Reparatur unter Verwendung der drei Netze berechnet. Aufgrund der Netzmechanik und der Netzporenverformung bietet das DynaMesh mit regelm{\"a}ßigen rechteckigen Netzporen eine bessere mechanische Unterst{\"u}tzung und eine Neupositionierung des Scheidengew{\"o}lbes, der Blase und der Urethraachse als Gynemesh und Ultrapro mit unregelm{\"a}ßigen hexagonalen Netzporen.}, language = {en} } @article{BirgelLeschingerWegmannetal.2018, author = {Birgel, Stefan and Leschinger, Tim and Wegmann, Kilian and Staat, Manfred}, title = {Calculation of muscle forces and joint reaction loads in the shoulder area via an OpenSim based computer model}, series = {tm - Technisches Messen}, volume = {85}, journal = {tm - Technisches Messen}, number = {5}, publisher = {De Gruyter}, address = {Berlin}, issn = {2196-7113}, doi = {10.1515/teme-2017-0114}, pages = {321 -- 330}, year = {2018}, abstract = {Using the OpenSim software and verified anatomical data, a computer model for the calculation of biomechanical parameters is developed and used to determine the effect of a reattachment of the Supraspinatus muscle with a medial displacement of the muscle attachment point, which may be necessary for a rupture of the supraspinatus tendon. The results include the influence of the operation on basic biomechanical parameters such as the lever arm, as well as the calculated the muscle activations for the supraspinatus and deltoid. In addition, the influence on joint stability is examined by an analysis of the joint reaction force. The study provides a detailed description of the used model, as well as medical findings to a reattachment of the supraspinatus. Mit der Software OpenSim und {\"u}berpr{\"u}ften anatomischen Daten wird ein Computermodell zur Berechnung von biomechanischen Parametern entwickelt und genutzt, um den Effekt einer Refixierung des Supraspinatusmuskels mit einer medialen Verschiebung des Muskelansatzpunktes zu ermitteln, wie sie unter anderem nach einem Riss der Supraspinatussehne notwendig sein kann. Die Ergebnisse umfassen hierbei den Einfluss der Operation auf grundlegende biomechanische Parameter wie den Hebelarm sowie die berechneten Muskelaktivierungen f{\"u}r den Supraspinatus und Deltoideus. Zus{\"a}tzlich wird der Einfluss auf die Gelenkstabilit{\"a}t betrachtet und durch eine Analyse der Gelenkreaktionskraft untersucht. Die Studie bietet eine detaillierte Beschreibung des genutzten Modells, sowie medizinische Erkenntnisse zu einer Refixierung des Supraspinatus.}, language = {en} } @article{BhattaraiStaat2018, author = {Bhattarai, Aroj and Staat, Manfred}, title = {Modelling of Soft Connective Tissues to Investigate Female Pelvic Floor Dysfunctions}, series = {Computational and Mathematical Methods in Medicine}, volume = {2018}, journal = {Computational and Mathematical Methods in Medicine}, number = {Article ID 9518076}, publisher = {Hindawi}, address = {New York, NY}, issn = {1748-6718}, doi = {10.1155/2018/9518076}, pages = {1 -- 16}, year = {2018}, abstract = {After menopause, decreased levels of estrogen and progesterone remodel the collagen of the soft tissues thereby reducing their stiffness. Stress urinary incontinence is associated with involuntary urine leakage due to pathological movement of the pelvic organs resulting from lax suspension system, fasciae, and ligaments. This study compares the changes in the orientation and position of the female pelvic organs due to weakened fasciae, ligaments, and their combined laxity. A mixture theory weighted by respective volume fraction of elastin-collagen fibre compound (5\%), adipose tissue (85\%), and smooth muscle (5\%) is adopted to characterize the mechanical behaviour of the fascia. The load carrying response (other than the functional response to the pelvic organs) of each fascia component, pelvic organs, muscles, and ligaments are assumed to be isotropic, hyperelastic, and incompressible. Finite element simulations are conducted during Valsalva manoeuvre with weakened tissues modelled by reduced tissue stiffness. A significant dislocation of the urethrovesical junction is observed due to weakness of the fascia (13.89 mm) compared to the ligaments (5.47 mm). The dynamics of the pelvic floor observed in this study during Valsalva manoeuvre is associated with urethral-bladder hypermobility, greater levator plate angulation, and positive Q-tip test which are observed in incontinent females.}, language = {en} } @article{HeinkeKnickerAlbracht2018, author = {Heinke, Lars N. and Knicker, Axel J. and Albracht, Kirsten}, title = {Evaluation of passively induced shoulder stretch reflex using an isokinetic dynamometer in male overhead athletes}, series = {Isokinetics and Exercise Science}, volume = {26}, journal = {Isokinetics and Exercise Science}, number = {4}, publisher = {IOS Press}, address = {Amsterdam}, issn = {1878-5913}, doi = {10.3233/IES-184111}, pages = {265 -- 274}, year = {2018}, abstract = {BACKGROUND: Muscle stretch reflexes are widely considered to beneficially influence joint stability and power generation in the lower limbs. While in the upper limbs and especially in the muscles surrounding the shoulder joint such evidence is lacking. OBJECTIVE: To quantify the electromyographical response in the muscles crossing the shoulder of specifically trained overhead athletes to an anterior perturbation force. METHODS: Twenty healthy male participants performed six sets of different external shoulder rotation stretches on an isokinetic dynamometer over a range of amplitudes and muscle pre-activation moment levels. All stretches were applied with a dynamometer acceleration of 10,000∘/s2 and a velocity of 150∘/s. Electromyographical response was measured via sEMG. RESULTS: Consistent reflexes were not observed in all experimental conditions. The reflex latencies revealed a significant muscle main effect (F (2,228) = 99.31, p< 0.001; η2= 0.466; f= 0.934) and a pre-activation main effect (F (1,228) = 142.21, p< 0.001; η2= 0.384; f= 1.418). The stretch reflex amplitude yielded a significant pre-activation main effect (F (1,222) = 470.373, p< 0.001; η2= 0.679; f= 1.454). CONCLUSION: Short latency muscle reflexes showed a tendency to an anterior to posterior muscle recruitment whereby the main internal rotator muscles of the shoulder revealed the most consistent results.}, 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{AlbannaKotliarLuekeetal.2018, author = {Albanna, Walid and Kotliar, Konstantin and L{\"u}ke, Jan Niklas and Alpdogan, Serdar and Conzen, Catharina and Lindauer, Ute and Clusmann, Hans and Hescheler, J{\"u}rgen and Vilser, Walthard and Schneider, Toni and Schubert, Gerrit Alexander}, title = {Non-invasive evaluation of neurovascular coupling in the murine retina by dynamic retinal vessel analysis}, series = {Plos one}, volume = {13}, journal = {Plos one}, number = {10}, publisher = {PLOS}, address = {San Francisco}, doi = {10.1371/journal.pone.0204689}, pages = {e0204689}, year = {2018}, abstract = {Background Impairment of neurovascular coupling (NVC) was recently reported in the context of subarachnoid hemorrhage and may correlate with disease severity and outcome. However, previous techniques to evaluate NVC required invasive procedures. Retinal vessels may represent an alternative option for non-invasive assessment of NVC. Methods A prototype of an adapted retinal vessel analyzer was used to assess retinal vessel diameter in mice. Dynamic vessel analysis (DVA) included an application of monochromatic flicker light impulses in predefined frequencies for evaluating NVC. All retinae were harvested after DVA and electroretinograms were performed. Results A total of 104 retinal scans were conducted in 21 male mice (90 scans). Quantitative arterial recordings were feasible only in a minority of animals, showing an emphasized reaction to flicker light impulses (8 mice; 14 scans). A characteristic venous response to flicker light, however, could observed in the majority of animals. Repeated measurements resulted in a significant decrease of baseline venous diameter (7 mice; 7 scans, p < 0.05). Ex-vivo electroretinograms, performed after in-vivo DVA, demonstrated a significant reduction of transretinal signaling in animals with repeated DVA (n = 6, p < 0.001). Conclusions To the best of our knowledge, this is the first non-invasive study assessing murine retinal vessel response to flicker light with characteristic changes in NVC. The imaging system can be used for basic research and enables the investigation of retinal vessel dimension and function in control mice and genetically modified animals.}, language = {en} } @article{BalakirskiKotliarPaulyetal.2018, author = {Balakirski, Galina and Kotliar, Konstantin and Pauly, Karolin J. and Krings, Laura K. and R{\"u}bben, Albert and Baron, Jens M. and Schmitt, Laurenz}, title = {Surgical Site Infections After Dermatologic Surgery in Immunocompromised Patients: A Single-Center Experience}, series = {Dermatologic Surgery}, journal = {Dermatologic Surgery}, number = {44 (12)}, publisher = {Wolters Kluwer}, doi = {10.1097/DSS.0000000000001615}, pages = {1525 -- 1536}, year = {2018}, abstract = {BACKGROUND Immunosuppression is often considered as an indication for antibiotic prophylaxis to prevent surgical site infections (SSI) while performing skin surgery. However, the data on the risk of developing SSI after dermatologic surgery in immunosuppressed patients are limited. PATIENTS AND METHODS All patients of the Department of Dermatology and Allergology at the University Hospital of RWTH Aachen in Aachen, Germany, who underwent hospitalization for a dermatologic surgery between June 2016 and January 2017 (6 months), were followed up after surgery until completion of the wound healing process. The follow-up addressed the occurrence of SSI and the need for systemic antibiotics after the operative procedure. Immunocompromised patients were compared with immunocompetent patients. The investigation was conducted as a retrospective analysis of patient records. RESULTS The authors performed 284 dermatologic surgeries in 177 patients. Nineteen percent (54/284) of the skin surgery was performed on immunocompromised patients. The most common indications for surgical treatment were nonmelanoma skin cancer and malignant melanomas. Surgical site infections occurred in 6.7\% (19/284) of the cases. In 95\% (18/19), systemic antibiotic treatment was needed. Twenty-one percent of all SSI (4/19) were seen in immunosuppressed patients. CONCLUSION According to the authors' data, immunosuppression does not represent a significant risk factor for SSI after dermatologic surgery. However, larger prospective studies are needed to make specific recommendations on the use of antibiotic prophylaxis while performing skin surgery in these patients. The available data on complications after dermatologic surgery have improved over the past years. Particularly, additional risk factors have been identified for surgical site infections (SSI). Purulent surgical sites, older age, involvement of head, neck, and acral regions, and also the involvement of less experienced surgeons have been reported to increase the risk of the SSI after dermatologic surgeries.1 In general, the incidence of SSI after skin surgery is considered to be low.1,2 However, antibiotics in dermatologic surgeries, especially in the perioperative setting, seem to be overused,3,4 particularly regarding developing antibiotic resistances and side effects. Immunosuppression has been recommended to be taken into consideration as an additional indication for antibiotic prophylaxis to prevent SSI after skin surgery in special cases.5,6 However, these recommendations do not specify the exact dermatologic surgeries, and were not specifically developed for dermatologic surgery patients and treatments, but adopted from other surgical fields.6 According to the survey conducted on American College of Mohs Surgery members in 2012, 13\% to 29\% of the surgeons administered antibiotic prophylaxis to immunocompromised patients to prevent SSI while performing dermatologic surgery on noninfected skin,3 although this was not recommended by Journal of the American Academy of Dermatology Advisory Statement. Indeed, the data on the risk of developing SSI after dermatologic surgery in immunosuppressed patients are limited. However, it is possible that due to the insufficient evidence on the risk of SSI occurrence in this patient group, dermatologic surgeons tend to overuse perioperative antibiotic prophylaxis. To make specific recommendations on the use of antibiotic prophylaxis in immunosuppressed patients in the field of skin surgery, more information about the incidence of SSI after dermatologic surgery in these patients is needed. The aim of this study was to fill this data gap by investigating whether there is an increased risk of SSI after skin surgery in immunocompromised patients compared with immunocompetent patients.}, language = {en} } @article{RittwegerAlbrachtFluecketal.2018, author = {Rittweger, J{\"o}rn and Albracht, Kirsten and Fl{\"u}ck, Martin and Ruoss, Severin and Brocca, Lorenza and Longa, Emanuela and Moriggi, Manuela and Seynnes, Olivier and Di Giulio, Irene and Tenori, Leonardo and Vignoli, Alessia and Capri, Miriam and Gelfi, Cecilia and Luchinat, Claudio and Franceschi, Claudio and Bottinelli, Roberto and Cerretelli, Paolo and Narici, Marco}, title = {Sarcolab pilot study into skeletal muscle's adaptation to longterm spaceflight}, series = {npj Microgravity}, volume = {4}, journal = {npj Microgravity}, number = {1}, publisher = {Nature Portfolio}, issn = {2373-8065}, doi = {10.1038/s41526-018-0052-1}, pages = {1 -- 9}, year = {2018}, language = {en} } @article{CiritsisHorbachStaatetal.2018, author = {Ciritsis, Alexander and Horbach, Andreas and Staat, Manfred and Kuhl, Christiane K. and Kraemer, Nils Andreas}, title = {Porosity and tissue integration of elastic mesh implants evaluated in vitro and in vivo}, series = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials}, volume = {106}, journal = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials}, number = {2}, publisher = {Wiley}, address = {New York, NY}, issn = {1552-4981}, doi = {10.1002/jbm.b.33877}, pages = {827 -- 833}, year = {2018}, abstract = {Purpose In vivo, a loss of mesh porosity triggers scar tissue formation and restricts functionality. The purpose of this study was to evaluate the properties and configuration changes as mesh deformation and mesh shrinkage of a soft mesh implant compared with a conventional stiff mesh implant in vitro and in a porcine model. Material and Methods Tensile tests and digital image correlation were used to determine the textile porosity for both mesh types in vitro. A group of three pigs each were treated with magnetic resonance imaging (MRI) visible conventional stiff polyvinylidene fluoride meshes (PVDF) or with soft thermoplastic polyurethane meshes (TPU) (FEG Textiltechnik mbH, Aachen, Germany), respectively. MRI was performed with a pneumoperitoneum at a pressure of 0 and 15 mmHg, which resulted in bulging of the abdomen. The mesh-induced signal voids were semiautomatically segmented and the mesh areas were determined. With the deformations assessed in both mesh types at both pressure conditions, the porosity change of the meshes after 8 weeks of ingrowth was calculated as an indicator of preserved elastic properties. The explanted specimens were examined histologically for the maturity of the scar (collagen I/III ratio). Results In TPU, the in vitro porosity increased constantly, in PVDF, a loss of porosity was observed under mild stresses. In vivo, the mean mesh areas of TPU were 206.8 cm2 (± 5.7 cm2) at 0 mmHg pneumoperitoneum and 274.6 cm2 (± 5.2 cm2) at 15 mmHg; for PVDF the mean areas were 205.5 cm2 (± 8.8 cm2) and 221.5 cm2 (± 11.8 cm2), respectively. The pneumoperitoneum-induced pressure increase resulted in a calculated porosity increase of 8.4\% for TPU and of 1.2\% for PVDF. The mean collagen I/III ratio was 8.7 (± 0.5) for TPU and 4.7 (± 0.7) for PVDF. Conclusion The elastic properties of TPU mesh implants result in improved tissue integration compared to conventional PVDF meshes, and they adapt more efficiently to the abdominal wall. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 827-833, 2018.}, language = {en} } @article{HorbachStaat2018, author = {Horbach, Andreas and Staat, Manfred}, title = {Optical strain measurement for the modeling of surgical meshes and their porosity}, series = {Current Directions in Biomedical Engineering}, volume = {Band 4}, journal = {Current Directions in Biomedical Engineering}, number = {1}, publisher = {De Gruyter}, address = {Berlin}, issn = {2364-5504}, doi = {10.1515/cdbme-2018-0045}, pages = {181 -- 184}, year = {2018}, abstract = {The porosity of surgical meshes makes them flexible for large elastic deformation and establishes the healing conditions of good tissue in growth. The biomechanic modeling of orthotropic and compressible materials requires new materials models and simulstaneoaus fit of deformation in the load direction as well as trannsversely to to load. This nonlinear modeling can be achieved by an optical deformation measurement. At the same time the full field deformation measurement allows the dermination of the change of porosity with deformation. Also the socalled effective porosity, which has been defined to asses the tisssue interatcion with the mesh implants, can be determined from the global deformation of the surgical meshes.}, language = {en} } @article{BhattaraiStaat2018, author = {Bhattarai, Aroj and Staat, Manfred}, title = {Computational comparison of different textile implants to correct apical prolapse in females}, series = {Current Directions in Biomedical Engineering}, volume = {4}, journal = {Current Directions in Biomedical Engineering}, number = {1}, publisher = {De Gruyter}, address = {Berlin}, doi = {10.1515/cdbme-2018-0159}, pages = {661 -- 664}, year = {2018}, abstract = {Prosthetic textile implants of different shapes, sizes and polymers are used to correct the apical prolapse after hysterectomy (removal of the uterus). The selection of the implant before or during minimally invasive surgery depends on the patient's anatomical defect, intended function after reconstruction and most importantly the surgeon's preference. Weakness or damage of the supporting tissues during childbirth, menopause or previous pelvic surgeries may put females in higher risk of prolapse. Numerical simulations of reconstructed pelvic floor with weakened tissues and organ supported by textile product models: DynaMesh®-PRS soft, DynaMesh®-PRP soft and DynaMesh®-CESA from FEG Textiletechnik mbH, Germany are compared.}, 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} } @article{WerkhausenAlbrachtCroninetal.2018, author = {Werkhausen, Amelie and Albracht, Kirsten and Cronin, Neil J and Paulsen, G{\o}ran and Bojsen-M{\o}ller, Jens and Seynnes, Olivier R}, title = {Effect of training-induced changes in achilles tendon stiffness on muscle-tendon behavior during landing}, series = {Frontiers in physiology}, journal = {Frontiers in physiology}, number = {9}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2018.00794}, pages = {11 Seiten}, year = {2018}, abstract = {During rapid deceleration of the body, tendons buffer part of the elongation of the muscle-tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle-tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarflexion force, peak Achilles tendon strain and stiffness were measured during isometric contractions, using a combination of dynamometry, ultrasound and kinematics data. Additionally, testing included a step-landing task, during which joint mechanics and lengths of gastrocnemius and soleus fascicles, Achilles tendon, and MTU were determined using synchronized ultrasound, kinematics and kinetics data collection. After training, plantarflexion strength and Achilles tendon stiffness increased (15 and 18\%, respectively), and tendon strain during landing remained similar. Likewise, lengthening and negative work produced by the gastrocnemius MTU did not change detectably. However, in the training group, gastrocnemius fascicle length was offset (8\%) to a longer length at touch down and, surprisingly, fascicle lengthening and velocity were reduced by 27 and 21\%, respectively. These changes were not observed for soleus fascicles when accounting for variation in task execution between tests. These results indicate that a training-induced increase in tendon stiffness does not noticeably affect the buffering action of the tendon when the MTU is rapidly stretched. Reductions in gastrocnemius fascicle lengthening and lengthening velocity during landing occurred independently from tendon strain. Future studies are required to provide insight into the mechanisms underpinning these observations and their influence on energy dissipation.}, 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} }