@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{KotliarOrtnerConradietal.2022, author = {Kotliar, Konstantin and Ortner, Marion and Conradi, Anna and Hacker, Patricia and Hauser, Christine and G{\"u}nthner, Roman and Moser, Michaela and Muggenthaler, Claudia and Diehl-Schmid, Janine and Priller, Josef and Schmaderer, Christoph and Grimmer, Timo}, title = {Altered retinal cerebral vessel oscillation frequencies in Alzheimer's disease compatible with impaired amyloid clearance}, series = {Neurobiology of Aging}, volume = {120}, journal = {Neurobiology of Aging}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0197-4580}, doi = {10.1016/j.neurobiolaging.2022.08.012}, pages = {117 -- 127}, year = {2022}, abstract = {Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis.}, language = {en} } @article{SchaelAtanasyanBerdugoetal.2019, author = {Schael, S. and Atanasyan, A. and Berdugo, J. and Bretz, T. and Czupalla, Markus and Dachwald, Bernd and Doetinchem, P. von and Duranti, M. and Gast, H. and Karpinski, W. and Kirn, T. and L{\"u}belsmeyer, K. and Ma{\~n}a, C. and Marrocchesi, P.S. and Mertsch, P. and Moskalenko, I.V. and Schervan, T. and Schluse, M. and Schr{\"o}der, K.-U. and Schultz von Dratzig, A. and Senatore, C. and Spies, L. and Wakely, S.P. and Wlochal, M. and Uglietti, D. and Zimmermann, J.}, title = {AMS-100: The next generation magnetic spectrometer in space - An international science platform for physics and astrophysics at Lagrange point 2}, series = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, volume = {944}, journal = {Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment}, number = {162561}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0168-9002}, doi = {10.1016/j.nima.2019.162561}, year = {2019}, language = {en} } @article{StaatVu2004, author = {Staat, Manfred and Vu, Duc-Khoi}, title = {An Algorithm for Shakedown Analysis for Materials with Temperature Dependent Yield Stress}, series = {Proceedings in Applied Mathematics and Mechanics (PAMM). 4 (2004), H. 1}, journal = {Proceedings in Applied Mathematics and Mechanics (PAMM). 4 (2004), H. 1}, isbn = {1617-7061}, pages = {231 -- 233}, year = {2004}, language = {en} } @article{VuStaat2004, author = {Vu, Duc-Khoi and Staat, Manfred}, title = {An algorithm for shakedown analysis of structure with temperature dependent yield stress}, year = {2004}, abstract = {This work is an attempt to answer the question: How to use convex programming in shakedown analysis of structures made of materials with temperature-dependent properties. Based on recently established shakedown theorems and formulations, a dual relationship between upper and lower bounds of the shakedown limit load is found, an algorithmfor shakedown analysis is proposed. While the original problem is neither convex nor concave, the algorithm presented here has the advantage of employing convex programming tools.}, subject = {Einspielen }, 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{ColomboDriraFrotscheretal.2022, author = {Colombo, Daniele and Drira, Slah and Frotscher, Ralf and Staat, Manfred}, title = {An element-based formulation for ES-FEM and FS-FEM models for implementation in standard solid mechanics finite element codes for 2D and 3D static analysis}, series = {International Journal for Numerical Methods in Engineering}, volume = {124}, journal = {International Journal for Numerical Methods in Engineering}, number = {2}, publisher = {Wiley}, address = {Chichester}, issn = {1097-0207}, doi = {10.1002/nme.7126}, pages = {402 -- 433}, year = {2022}, abstract = {Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element.}, 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{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{Staat2021, author = {Staat, Manfred}, title = {An extension strain type Mohr-Coulomb criterion}, series = {Rock mechanics and rock engineering}, volume = {54}, journal = {Rock mechanics and rock engineering}, number = {12}, publisher = {Springer Nature}, address = {Cham}, issn = {1434-453X}, doi = {10.1007/s00603-021-02608-7}, pages = {6207 -- 6233}, year = {2021}, abstract = {Extension fractures are typical for the deformation under low or no confining pressure. They can be explained by a phenomenological extension strain failure criterion. In the past, a simple empirical criterion for fracture initiation in brittle rock has been developed. In this article, it is shown that the simple extension strain criterion makes unrealistic strength predictions in biaxial compression and tension. To overcome this major limitation, a new extension strain criterion is proposed by adding a weighted principal shear component to the simple criterion. The shear weight is chosen, such that the enriched extension strain criterion represents the same failure surface as the Mohr-Coulomb (MC) criterion. Thus, the MC criterion has been derived as an extension strain criterion predicting extension failure modes, which are unexpected in the classical understanding of the failure of cohesive-frictional materials. In progressive damage of rock, the most likely fracture direction is orthogonal to the maximum extension strain leading to dilatancy. The enriched extension strain criterion is proposed as a threshold surface for crack initiation CI and crack damage CD and as a failure surface at peak stress CP. Different from compressive loading, tensile loading requires only a limited number of critical cracks to cause failure. Therefore, for tensile stresses, the failure criteria must be modified somehow, possibly by a cut-off corresponding to the CI stress. Examples show that the enriched extension strain criterion predicts much lower volumes of damaged rock mass compared to the simple extension strain criterion.}, language = {en} } @article{StaatKuehnHaugeretal.2004, author = {Staat, Manfred and K{\"u}hn, R. and Hauger, W. and Sponagel, Stefan}, title = {An Interpretation of Wolff's Law}, series = {Biomedizinische Technik. 49 (2004)}, journal = {Biomedizinische Technik. 49 (2004)}, isbn = {0932-4666}, pages = {1020 -- 1021}, year = {2004}, language = {de} } @article{AbelKahmannMellonetal.2020, author = {Abel, Alexander and Kahmann, Stephanie Lucina and Mellon, Stephen and Staat, Manfred and Jung, Alexander}, title = {An open-source tool for the validation of finite element models using three-dimensional full-field measurements}, series = {Medical Engineering \& Physics}, volume = {77}, journal = {Medical Engineering \& Physics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1350-4533}, doi = {10.1016/j.medengphy.2019.10.015}, pages = {125 -- 129}, year = {2020}, abstract = {Three-dimensional (3D) full-field measurements provide a comprehensive and accurate validation of finite element (FE) models. For the validation, the result of the model and measurements are compared based on two respective point-sets and this requires the point-sets to be registered in one coordinate system. Point-set registration is a non-convex optimization problem that has widely been solved by the ordinary iterative closest point algorithm. However, this approach necessitates a good initialization without which it easily returns a local optimum, i.e. an erroneous registration. The globally optimal iterative closest point (Go-ICP) algorithm has overcome this drawback and forms the basis for the presented open-source tool that can be used for the validation of FE models using 3D full-field measurements. The capability of the tool is demonstrated using an application example from the field of biomechanics. Methodological problems that arise in real-world data and the respective implemented solution approaches are discussed.}, 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{LeversStaatLaack2011, author = {Levers, A. and Staat, Manfred and Laack, Walter van}, title = {Analyse der Langzeitwirkung der MBST® KernspinResonanzTherapie bei Gonarthrose}, year = {2011}, abstract = {Originalausgabe: Orthop{\"a}dische Praxis Jg. 47. 2011 H. 11; S. 536-543. Mit freundlicher Genehmigung des Verlags Zusammenfassung: Auf der Basis von Patientenabfragen mittels Fragebogen zum Schmerzempfinden und zur Einschr{\"a}nkung bei Aktivit{\"a}ten des allt{\"a}glichen Lebens wird die Langzeitwirkung der MBST® KernspinResonanz-Therapie bei Gonarthrose untersucht. An der Studie nahmen 39 Patienten teil, bei denen die Therapie bis zu vier Jahre zur{\"u}ckliegt. Neben einer Gesamtbetrachtung wird der Erfolg auch in Abh{\"a}ngigkeit von Alter, Geschlecht und sportlicher Aktivit{\"a}t analysiert. Insgesamt weist die Studie auf eine anhaltende Verbesserung des Gesundheitszustands mit zum Teil deutlicher Schmerzlinderung auch noch nach vier Jahren hin, jedoch mit einer leichten Schmerzzunahme gegen Ende des Untersuchungszeitraums von vier Jahren. Eine tendenziell positivere Wirkung bei Frauen, {\"a}lteren Menschen oder auch sportlich nicht-aktiven Patienten l{\"a}sst auf eine m{\"o}gliche Beeinflussung des Erfolgs der Therapie durch ({\"U}ber-)Belastung im Alltag schließen. Ein zus{\"a}tzlich positiver Effekt der Therapie auf die Knochendichte ist ebenfalls denkbar, dies bleibt jedoch offen.}, subject = {Kniegelenkarthrose}, language = {de} } @article{VuStaatTran2007, author = {Vu, Duc Khoi and Staat, Manfred and Tran, Ich Thinh}, title = {Analysis of pressure equipment by application of the primal-dual theory of shakedown}, series = {Communications in Numerical Methods in Engineering. 23 (2007), H. 3}, journal = {Communications in Numerical Methods in Engineering. 23 (2007), H. 3}, isbn = {1069-8299}, pages = {213 -- 225}, year = {2007}, 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{Sponagel1987, author = {Sponagel, Stefan}, title = {Analytische Berechnung von Gummi- Metall- Verbindungen}, series = {Konstruktion : Zeitschrift f{\"u}r Produktentwicklung. 39 (1987), H. 4}, journal = {Konstruktion : Zeitschrift f{\"u}r Produktentwicklung. 39 (1987), H. 4}, isbn = {0373-3300}, pages = {151 -- 158}, year = {1987}, language = {de} } @article{StaatBallmann1985, author = {Staat, Manfred and Ballmann, J.}, title = {Anisotrope Ausbreitung und Fokussierung von Beschleunigungswellen in vorgespannten nichtlinearelastischen Scheiben}, series = {Wellenfokussierung, Kolloquium des SFB 27, RWTH Aachen}, journal = {Wellenfokussierung, Kolloquium des SFB 27, RWTH Aachen}, address = {Aachen}, pages = {140 -- 158}, year = {1985}, language = {de} } @article{Staat1987, author = {Staat, Manfred}, title = {Anisotrope Wellenausbreitung in isotropen hyperelastischen Scheiben}, series = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik : ZAMM. 67 (1987), H. 4}, journal = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik : ZAMM. 67 (1987), H. 4}, isbn = {0946-8463}, pages = {T241 -- T243}, year = {1987}, language = {de} } @article{SavitskayaKistaubayevaIgnatovaetal.2019, author = {Savitskaya, I.S. and Kistaubayeva, A.S. and Ignatova, L.V. and Digel, Ilya}, title = {Antimicrobial and wound healing properties of a bacterial cellulose based material containing B. subtilis cells}, series = {Heliyon}, volume = {5}, journal = {Heliyon}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2405-8440}, doi = {10.1016/j.heliyon.2019.e02592}, pages = {Artikelnummer e02592}, year = {2019}, language = {en} } @article{MurganBeyerKotliaretal.2013, author = {Murgan, Ilina and Beyer, Sonja and Kotliar, Konstantin and Weber, Lutz and Bechtold-Dalla Pozza, Susanne and Dalla Pozza, Robert and Wegner, Aharon and Sitnikova, Diana and Stock, Konrad and Heemann, Uwe and Schmaderer, Christoph and Baumann, M.}, title = {Arterial and Retinal Vascular Changes in Hypertensive and Prehypertensive Adolescents}, series = {American Journal of Hypertension}, volume = {26}, journal = {American Journal of Hypertension}, number = {3}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1941-7225}, pages = {400 -- 408}, year = {2013}, language = {de} } @article{ErmolaevErichevAntonovetal.2019, author = {Ermolaev, AP and Erichev, VP and Antonov, AA and Grigoryan, GL and Kotliar, Konstantin and Levitsky, YV and Hderi, K and Mazurova, YV}, title = {Assessing retinal photosensitivity in patients with central vision impairment using a portable perimeter (a preliminary report)}, series = {Vestnik oftalmologii}, volume = {135}, journal = {Vestnik oftalmologii}, number = {3}, doi = {10.17116/oftalma201913503146}, pages = {46 -- 54}, year = {2019}, language = {ru} } @article{BogoyavlenskiyDigelBerezin1997, author = {Bogoyavlenskiy, A. P. and Digel, Ilya and Berezin, V. E.}, title = {Assessment of dot-blot ELISA sensitivity on membrane sorbent using various peroxidase substrates}, year = {1997}, abstract = {The sensitivity of the peroxidase reaction in dot-blot ELISA significantly depends on the substrate. The highest sensitivity is observed using benzidine and diamine- phenol combinations as the substrates due to the reaction of the coupled oxidation (NADI)}, subject = {Enzyme-linked immunosorbent assay}, language = {en} } @article{AlbrachtArampatzisBaltzopoulos2008, author = {Albracht, Kirsten and Arampatzis, A. and Baltzopoulos, V.}, title = {Assessment of muscle volume and physiological cross-sectional area of the human triceps surae muscle in vivo}, series = {Journal of Biomechanics}, volume = {41}, journal = {Journal of Biomechanics}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2008.04.020}, pages = {2211 -- 2218}, year = {2008}, language = {en} } @article{BehbahaniSpillnerKoppetal.2009, author = {Behbahani, Mehdi and Spillner, Jan and Kopp, R{\"u}diger and Finocchiaro, Thomas}, title = {Assistierte Zirkulation : ein {\"U}berblick aus klinischer Sicht = Assisted circulation: an overview from a clinical perspective / Spillner, Jan ; Kopp, R{\"u}diger ; Finocchiaro, Thomas ; Behbahani, Mehdi ; Rossaint, Rolf ; Steinseifer, Ulrich ; Behr, Marek ; Au}, series = {Biomedizinische Technik / Biomedical Engineering. 54 (2009), H. 5}, journal = {Biomedizinische Technik / Biomedical Engineering. 54 (2009), H. 5}, publisher = {De Gruyter}, address = {Berlin}, isbn = {0013-5585}, pages = {255 -- 267}, year = {2009}, language = {de} } @article{PogorelovaRogachevDigeletal.2020, author = {Pogorelova, Natalia and Rogachev, Evgeniy and Digel, Ilya and Chernigova, Svetlana and Nardin, Dmitry}, title = {Bacterial Cellulose Nanocomposites: Morphology and Mechanical Properties}, series = {Materials}, volume = {13}, journal = {Materials}, number = {12}, publisher = {MDPI}, address = {Basel}, isbn = {1996-1944}, doi = {10.3390/ma13122849}, pages = {1 -- 16}, year = {2020}, abstract = {Bacterial cellulose (BC) is a promising material for biomedical applications due to its unique properties such as high mechanical strength and biocompatibility. This article describes the microbiological synthesis, modification, and characterization of the obtained BC-nanocomposites originating from symbiotic consortium Medusomyces gisevii. Two BC-modifications have been obtained: BC-Ag and BC-calcium phosphate (BC-Ca3(PO4)2). Structure and physicochemical properties of the BC and its modifications were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), and infrared Fourier spectroscopy as well as by measurements of mechanical and water holding/absorbing capacities. Topographic analysis of the surface revealed multicomponent thick fibrils (150-160 nm in diameter and about 15 µm in length) constituted by 50-60 nm nanofibrils weaved into a left-hand helix. Distinctive features of Ca-phosphate-modified BC samples were (a) the presence of 500-700 nm entanglements and (b) inclusions of Ca3(PO4)2 crystals. The samples impregnated with Ag nanoparticles exhibited numerous roundish inclusions, about 110 nm in diameter. The boundaries between the organic and inorganic phases were very distinct in both cases. The Ag-modified samples also showed a prominent waving pattern in the packing of nanofibrils. The obtained BC gel films possessed water-holding capacity of about 62.35 g/g. However, the dried (to a constant mass) BC-films later exhibited a low water absorption capacity (3.82 g/g). It was found that decellularized BC samples had 2.4 times larger Young's modulus and 2.2 times greater tensile strength as compared to dehydrated native BC films. We presume that this was caused by molecular compaction of the BC structure.}, language = {en} } @article{DigelAkimbekovRogachevetal.2023, author = {Digel, Ilya and Akimbekov, Nuraly and Rogachev, Evgeniy and Pogorelova, Natalia}, title = {Bacterial cellulose produced by Medusomyces gisevii on glucose and sucrose: biosynthesis and structural properties}, series = {Cellulose}, journal = {Cellulose}, publisher = {Springer Science + Business Media}, address = {Dordrecht}, issn = {1572-882X (Online)}, doi = {10.1007/s10570-023-05592-z}, pages = {15 Seiten}, year = {2023}, abstract = {In this work, the effects of carbon sources and culture media on the production and structural properties of bacterial cellulose (BC) synthesized by Medusomyces gisevii have been studied. The culture medium was composed of different initial concentrations of glucose or sucrose dissolved in 0.4\% extract of plain green tea. Parameters of the culture media (titratable acidity, substrate conversion degree etc.) were monitored daily for 20 days of cultivation. The BC pellicles produced on different carbon sources were characterized in terms of biomass yield, crystallinity and morphology by field emission scanning electron microscopy (FE-SEM), atomic force microscopy and X-ray diffraction. Our results showed that Medusomyces gisevii had higher BC yields in media with sugar concentrations close to 10 g L-1 after a 18-20 days incubation period. Glucose in general lead to a higher BC yield (173 g L-1) compared to sucrose (163.5 g L-1). The BC crystallinity degree and surface roughness were higher in the samples synthetized from sucrose. Obtained FE-SEM micrographs show that the BC pellicles synthesized in the sucrose media contained densely packed tangles of cellulose fibrils whereas the BC produced in the glucose media displayed rather linear geometry of the BC fibrils without noticeable aggregates.}, language = {en} } @article{DigelTemizArtmannNishikawaetal.2005, author = {Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Nishikawa, K. and Cook, M.}, title = {Bactericidal effects of plasma-generated cluster ions}, series = {Medical and Biological Engineering and Computing. 43 (2005), H. 6}, journal = {Medical and Biological Engineering and Computing. 43 (2005), H. 6}, isbn = {1741-0444}, pages = {800 -- 807}, year = {2005}, language = {en} } @article{Staat2000, author = {Staat, Manfred}, title = {Basis Reduction for the Shakedown Problem for Bounded Kinematic Hardening Material}, year = {2000}, abstract = {Limit and shakedown analysis are effective methods for assessing the load carrying capacity of a given structure. The elasto-plastic behavior of the structure subjected to loads varying in a given load domain is characterized by the shakedown load factor, defined as the maximum factor which satisfies the sufficient conditions stated in the corresponding static shakedown theorem. The finite element dicretization of the problem may lead to very large convex optimization. For the effective solution a basis reduction method has been developed that makes use of the special problem structure for perfectly plastic material. The paper proposes a modified basis reduction method for direct application to the two-surface plasticity model of bounded kinematic hardening material. The considered numerical examples show an enlargement of the load carrying capacity due to bounded hardening.}, subject = {Finite-Elemente-Methode}, language = {en} } @article{MansurovDigelBiisenbaevetal.2012, author = {Mansurov, Z. and Digel, Ilya and Biisenbaev, M. and Savistkaya, I. and Kistaubaeva, A. and Akimbekov, N. 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{UysalCreutzFiratetal.2022, author = {Uysal, Karya and Creutz, Till and Firat, Ipek Seda and Artmann, Gerhard and Teusch, Nicole and Temiz Artmann, Ayseg{\"u}l}, title = {Bio-functionalized ultra-thin, large-area and waterproof silicone membranes for biomechanical cellular loading and compliance experiments}, series = {Polymers}, volume = {14}, journal = {Polymers}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, pages = {2213}, year = {2022}, abstract = {Biocompatibility, flexibility and durability make polydimethylsiloxane (PDMS) membranes top candidates in biomedical applications. CellDrum technology uses large area, <10 µm thin membranes as mechanical stress sensors of thin cell layers. For this to be successful, the properties (thickness, temperature, dust, wrinkles, etc.) must be precisely controlled. The following parameters of membrane fabrication by means of the Floating-on-Water (FoW) method were investigated: (1) PDMS volume, (2) ambient temperature, (3) membrane deflection and (4) membrane mechanical compliance. Significant differences were found between all PDMS volumes and thicknesses tested (p < 0.01). They also differed from the calculated values. At room temperatures between 22 and 26 °C, significant differences in average thickness values were found, as well as a continuous decrease in thicknesses within a 4 °C temperature elevation. No correlation was found between the membrane thickness groups (between 3-4 µm) in terms of deflection and compliance. We successfully present a fabrication method for thin bio-functionalized membranes in conjunction with a four-step quality management system. The results highlight the importance of tight regulation of production parameters through quality control. The use of membranes described here could also become the basis for material testing on thin, viscous layers such as polymers, dyes and adhesives, which goes far beyond biological applications.}, language = {en} } @article{AkimbekovDigelTastambeketal.2013, author = {Akimbekov, N. 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{MaggakisKelemenBorkKayseretal.2003, author = {Maggakis-Kelemen, C. and Bork, M. and Kayser, Peter and Biselli, Manfred and Artmann, Gerhard}, title = {Biological and mechanical quality of red blood cells cultured from human umbilical cord blood stem cells}, series = {Medical and biological engineering and computing. 41 (2003), H. 3}, journal = {Medical and biological engineering and computing. 41 (2003), H. 3}, isbn = {0140-0118}, pages = {350 -- 356}, year = {2003}, language = {en} } @article{KotliarKoshitzSvetlowaetal.2005, author = {Kotliar, Konstantin and Koshitz, I. N. and Svetlowa, O. V. and Makarov, F. N.}, title = {Biomechanical analysis of traditional and contemporary conceptions on pathogenesis of the primary open angle glaucoma / Koshitz, I. N. ; Svetlova, O. V. ; Kotliar, K. E. ; Makarov, F. N. ; Smolnikov, B. A.}, series = {Glaukoma (2005)}, journal = {Glaukoma (2005)}, publisher = {-}, pages = {41 -- 63}, year = {2005}, language = {en} } @article{HorbachStaatPerezVianaetal.2020, author = {Horbach, Andreas and Staat, Manfred and Perez-Viana, Daniel and Simmen, Hans-Peter and Neuhaus, Valentin and Pape, Hans-Christoph and Prescher, Andreas and Ciritsis, Bernhard}, title = {Biomechanical in vitro examination of a standardized low-volume tubular femoroplasty}, series = {Clinical Biomechanics}, volume = {80}, journal = {Clinical Biomechanics}, number = {Art. 105104}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.clinbiomech.2020.105104}, year = {2020}, abstract = {Background Osteoporosis is associated with the risk of fractures near the hip. Age and comorbidities increase the perioperative risk. Due to the ageing population, fracture of the proximal femur also proves to be a socio-economic problem. Preventive surgical measures have hardly been used so far. Methods 10 pairs of human femora from fresh cadavers were divided into control and low-volume femoroplasty groups and subjected to a Hayes fall-loading fracture test. The results of the respective localization and classification of the fracture site, the Singh index determined by computed tomography (CT) examination and the parameters in terms of fracture force, work to fracture and stiffness were evaluated statistically and with the finite element method. In addition, a finite element parametric study with different position angles and variants of the tubular geometry of the femoroplasty was performed. Findings Compared to the control group, the work to fracture could be increased by 33.2\%. The fracture force increased by 19.9\%. The used technique and instrumentation proved to be standardized and reproducible with an average poly(methyl methacrylate) volume of 10.5 ml. The parametric study showed the best results for the selected angle and geometry. Interpretation The cadaver studies demonstrated the biomechanical efficacy of the low-volume tubular femoroplasty. The numerical calculations confirmed the optimal choice of positioning as well as the inner and outer diameter of the tube in this setting. The standardized minimally invasive technique with the instruments developed for it could be used in further comparative studies to confirm the measured biomechanical results.}, language = {en} } @article{KotliarLanzl2002, author = {Kotliar, Konstantin and Lanzl, I. M.}, title = {Biomechanical modeling of the aqueous humor outflow after non-penetrating glaucoma filtration surgery in the human eye}, series = {Acta of bioengineering and biomechanics}, volume = {Vol. 4}, journal = {Acta of bioengineering and biomechanics}, number = {Suppl. 1}, issn = {1509-409X}, pages = {728 -- 729}, year = {2002}, language = {de} } @article{KotliarSvetlovaSourjikovetal.2004, author = {Kotliar, Konstantin and Svetlova, O. V. and Sourjikov, A. V. and Zaseeva, M. V.}, title = {Biomechanical peculiarities of aqueous humor production system and outflow regulation system / Svetlova, O. V. ; Sourjikov, A. V. ; Kotliar, K. E. ; Zaseeva, M. V. ; Shukhaev, S. V. ; Koshitz, I. N.}, series = {Glaukoma (2004)}, journal = {Glaukoma (2004)}, publisher = {-}, pages = {66 -- 76}, year = {2004}, language = {en} } @article{KotliarSvetlovaStegaevetal.2004, author = {Kotliar, Konstantin and Svetlova, O. V. and Stegaev, V. A. and Parkhomov, S. D.}, title = {Biomechanical substantiation of relatively low efficiency of recurrent laser trabeculoplasty / Svetlova, O. V. ; Stagaev, V. A. ; Parkhomov, S. D. ; Kotliar, K. E. ; Makarov, F. N. ; Smolnikov, B. A. ; Koshitz, I. N.}, series = {Glaukoma (2004)}, journal = {Glaukoma (2004)}, publisher = {-}, pages = {29 -- 39}, year = {2004}, language = {en} } @article{QuittmannAbelAlbrachtetal.2022, author = {Quittmann, Oliver J. and Abel, Thomas and Albracht, Kirsten and Str{\"u}der, Heiko K.}, title = {Biomechanics of all-out handcycling exercise: kinetics, kinematics and muscular activity of a 15-s sprint test in able-bodied participants}, series = {Sports Biomechanics}, volume = {21}, journal = {Sports Biomechanics}, number = {10}, publisher = {Taylor \& Francis}, address = {London}, issn = {1752-6116 (Onlineausgabe)}, doi = {10.1080/14763141.2020.1745266}, pages = {1200 -- 1223}, year = {2022}, abstract = {This study aims to quantify the kinematics, kinetics and muscular activity of all-out handcycling exercise and examine their alterations during the course of a 15-s sprint test. Twelve able-bodied competitive triathletes performed a 15-s all-out sprint test in a recumbent racing handcycle that was attached to an ergometer. During the sprint test, tangential crank kinetics, 3D joint kinematics and muscular activity of 10 muscles of the upper extremity and trunk were examined using a power metre, motion capturing and surface electromyography (sEMG), respectively. Parameters were compared between revolution one (R1), revolution two (R2), the average of revolution 3 to 13 (R3) and the average of the remaining revolutions (R4). Shoulder abduction and internal-rotation increased, whereas maximal shoulder retroversion decreased during the sprint. Except for the wrist angles, angular velocity increased for every joint of the upper extremity. Several muscles demonstrated an increase in muscular activation, an earlier onset of muscular activation in crank cycle and an increased range of activation. During the course of a 15-s all-out sprint test in handcycling, the shoulder muscles and the muscles associated to the push phase demonstrate indications for short-duration fatigue. These findings are helpful to prevent injuries and improve performance in all-out handcycling.}, language = {en} } @article{QuittmannAbelAlbrachtetal.2020, author = {Quittmann, Oliver J. and Abel, Thomas and Albracht, Kirsten and Meskemper, Joshua and Foitschik, Tina and Str{\"u}der, Heiko K.}, title = {Biomechanics of handcycling propulsion in a 30-min continuous load test at lactate threshold: Kinetics, kinematics, and muscular activity in able-bodied participants}, series = {European Journal of Applied Physiology}, journal = {European Journal of Applied Physiology}, number = {120}, publisher = {Springer}, address = {Heidelberg}, issn = {1439-6327}, doi = {10.1007/s00421-020-04373-x}, pages = {1403 -- 1415}, year = {2020}, abstract = {Purpose This study aims to investigate the biomechanics of handcycling during a continuous load trial (CLT) to assess the mechanisms underlying fatigue in upper body exercise. Methods Twelve able-bodied triathletes performed a 30-min CLT at a power output corresponding to lactate threshold in a racing recumbent handcycle mounted on a stationary ergometer. During the CLT, ratings of perceived exertion (RPE), tangential crank kinetics, 3D joint kinematics, and muscular activity of ten muscles of the upper extremity and trunk were examined using motion capturing and surface electromyography. Results During the CLT, spontaneously chosen cadence and RPE increased, whereas crank torque decreased. Rotational work was higher during the pull phase. Peripheral RPE was higher compared to central RPE. Joint range of motion decreased for elbow-flexion and radial-duction. Integrated EMG (iEMG) increased in the forearm flexors, forearm extensors, and M. deltoideus (Pars spinalis). An earlier onset of activation was found for M. deltoideus (Pars clavicularis), M. pectoralis major, M. rectus abdominis, M. biceps brachii, and the forearm flexors. Conclusion Fatigue-related alterations seem to apply analogously in handcycling and cycling. The most distal muscles are responsible for force transmission on the cranks and might thus suffer most from neuromuscular fatigue. The findings indicate that peripheral fatigue (at similar lactate values) is higher in handcycling compared to leg cycling, at least for inexperienced participants. An increase in cadence might delay peripheral fatigue by a reduced vascular occlusion. We assume that the gap between peripheral and central fatigue can be reduced by sport-specific endurance training.}, language = {en} } @article{KotliarVolkovKoshitsetal.1997, author = {Kotliar, Konstantin and Volkov, V. V. and Koshits, I. N. and Svetlova, O. V.}, title = {Biomekhanicheskie osobennosti vzaimodeĭstviia drenazhno i akkomodatsionnoĭ reguliatornykh sistem glaza v norme i pri kontuzionnom podvyvikhe khrustalika / Volkov, V. V. ; Kotliar, K. E. ; Koshits, I. n. ; Svetlova, O. V. ; Smol´nikov, B. A.}, series = {Vestnik oftalmologii. 113 (1997), H. 3}, journal = {Vestnik oftalmologii. 113 (1997), H. 3}, publisher = {-}, isbn = {0042-465X}, pages = {5 -- 7}, year = {1997}, language = {en} } @article{BorkKelemenBisellietal.2000, author = {Bork, M. and Kelemen, C. and Biselli, Manfred and Artmann, Gerhard}, title = {Biophysikalische Charakterisierung ex vivo kultivierter menschlicher Erythrozythen}, series = {Biomedizinische Technik = Biomedical Engineering. 45 (2000), H. s1}, journal = {Biomedizinische Technik = Biomedical Engineering. 45 (2000), H. s1}, isbn = {1862-278X}, pages = {471 -- 472}, year = {2000}, language = {de} } @article{AkimbekovDigelTastambeketal.2022, author = {Akimbekov, Nuraly S. and Digel, Ilya and Tastambek, Kuanysh T. and Marat, Adel K. and Turaliyeva, Moldir A. and Kaiyrmanova, Gulzhan K.}, title = {Biotechnology of Microorganisms from Coal Environments: From Environmental Remediation to Energy Production}, series = {Biology}, volume = {11}, journal = {Biology}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2079-7737}, doi = {10.3390/biology11091306}, pages = {47 Seiten}, year = {2022}, abstract = {It was generally believed that coal sources are not favorable as live-in habitats for microorganisms due to their recalcitrant chemical nature and negligible decomposition. However, accumulating evidence has revealed the presence of diverse microbial groups in coal environments and their significant metabolic role in coal biogeochemical dynamics and ecosystem functioning. The high oxygen content, organic fractions, and lignin-like structures of lower-rank coals may provide effective means for microbial attack, still representing a greatly unexplored frontier in microbiology. Coal degradation/conversion technology by native bacterial and fungal species has great potential in agricultural development, chemical industry production, and environmental rehabilitation. Furthermore, native microalgal species can offer a sustainable energy source and an excellent bioremediation strategy applicable to coal spill/seam waters. Additionally, the measures of the fate of the microbial community would serve as an indicator of restoration progress on post-coal-mining sites. This review puts forward a comprehensive vision of coal biodegradation and bioprocessing by microorganisms native to coal environments for determining their biotechnological potential and possible applications.}, language = {en} } @article{DigelMaggakisKelemenZerlinetal.2006, author = {Digel, Ilya and Maggakis-Kelemen, Christina and Zerlin, Kay and Linder, Peter}, title = {Body temperature-related structural transitions of monotremal and human hemoglobin}, series = {Biophysical Journal. 91 (2006), H. 8}, journal = {Biophysical Journal. 91 (2006), H. 8}, isbn = {1542-0086}, pages = {3014 -- 3021}, year = {2006}, 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{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{KotliarLanzl2011, author = {Kotliar, Konstantin and Lanzl, Ines M.}, title = {Can vascular function be assessed by the interpretation of retinal vascular diameter changes?}, series = {Investigative Ophthalmology \& Visual Science, IOVS. 52 (2011), H. 1}, journal = {Investigative Ophthalmology \& Visual Science, IOVS. 52 (2011), H. 1}, publisher = {ARVO}, address = {Rockville, Md.}, isbn = {0146-0404}, pages = {635 -- 636}, year = {2011}, language = {en} } @article{TemizArtmannYalcinResmietal.2002, author = {Temiz Artmann, Ayseg{\"u}l and Yalcin, Ozlem and Resmi, Halil and Baskurt, Oguz K.}, title = {Can white blood cell activation be one of the major factors that affect hemorheological parameters during and after exercise?}, series = {Clinical Hemorheology and Microcirculation. 26 (2002), H. 3}, journal = {Clinical Hemorheology and Microcirculation. 26 (2002), H. 3}, isbn = {1386-0291}, pages = {189 -- 193}, year = {2002}, language = {en} } @article{JanThimoBauerBieleetal.2019, author = {Jan Thimo, Grundmann and Bauer, Waldemar and Biele, Jens and Boden, Ralf and Ceriotti, Matteo and Cordero, Federico and Dachwald, Bernd and Dumont, Etienne and Grimm, Christian D. and Hercik, David}, title = {Capabilities of Gossamer-1 derived small spacecraft solar sails carrying Mascot-derived nanolanders for in-situ surveying of NEAs}, series = {Acta Astronautica}, volume = {156}, journal = {Acta Astronautica}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0094-5765}, doi = {10.1016/j.actaastro.2018.03.019}, pages = {330 -- 362}, year = {2019}, language = {en} } @article{Artmann2000, author = {Artmann, Gerhard}, title = {Cellular engineering - a challenge for engineers? / Artmann, G. M.}, series = {Biomedizinische Technik = Biomedical Engineering. 45 (2000), H. s1}, journal = {Biomedizinische Technik = Biomedical Engineering. 45 (2000), H. s1}, isbn = {1862-278X}, pages = {449}, year = {2000}, language = {en} }