@phdthesis{Oflaz2012, author = {Oflaz, Hakan}, title = {Entwicklung eines Prototypen zur Prognose von Fr{\"u}hgeburten : ein biomedizintechnischer Ansatz}, publisher = {Deutsche Zentralbibliothek f{\"u}r Medizin}, address = {K{\"o}ln}, doi = {10.4126/38m-004639208}, year = {2012}, language = {en} } @phdthesis{Behbahani2011, author = {Behbahani, Mehdi}, title = {Modeling and Simulation of Shear-Dependent Platelet Reactions in Blood Vessels and Blood-Contacting Medical Devices}, publisher = {Verlag Dr. Hut}, address = {M{\"u}nchen}, isbn = {978-3-8439-0134-5}, year = {2011}, language = {en} } @phdthesis{KurulganDemirci2012, author = {Kurulgan Demirci, Eylem}, title = {The effect of rhAPC on contractile tension : an in-vitro sepsis model of cardiomyocytes and endothelial cells}, year = {2012}, language = {en} } @phdthesis{Trzewik2007, author = {Trzewik, J{\"u}rgen}, title = {Experimental analysis of biaxial mechanical tension in cell monolayers and cultured three-dimensional tissues: the celldrum technology}, publisher = {Univerist{\"a}tsverlg Ilmenau}, address = {Ilmenau}, year = {2007}, language = {en} } @phdthesis{Pham2011, author = {Pham, Phu Tinh}, title = {Upper bound limit and shakedown analysis of elastic-plastic bounded linearly kinematic hardening structures}, publisher = {RWTH Aachen University}, address = {Aachen}, pages = {140 S.}, year = {2011}, language = {en} } @phdthesis{Tran2008, author = {Tran, Thanh Ngoc}, title = {Limit and shakedown analysis of plates and shells including uncertainties}, year = {2008}, language = {en} } @book{StaatHeitzer2003, author = {Staat, Manfred and Heitzer, Michael}, title = {Numerical methods for limit and shakedown analysis. Deterministic and probabilistic problems.}, publisher = {John von Neumann Institute for Computing (NIC)}, address = {J{\"u}lich}, isbn = {3-00-010001-6}, pages = {2, xiii, 282 Seiten}, year = {2003}, 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{AkimbekovDigelSherelkhanetal.2020, author = {Akimbekov, Nuraly S. and Digel, Ilya and Sherelkhan, Dinara K. and Lutfor, Afzalunnessa B. and Razzaque, Mohammed S.}, title = {Vitamin D and the Host-Gut Microbiome: A Brief Overview}, series = {Acta Histochemica et Cytochemica}, volume = {53}, journal = {Acta Histochemica et Cytochemica}, number = {3}, publisher = {Japan Society of Histochemistry and Cytochemistry}, address = {Osaka}, issn = {1347-5800}, doi = {10.1267/ahc.20011}, pages = {33 -- 42}, year = {2020}, abstract = {There is a growing body of evidence for the effects of vitamin D on intestinal host-microbiome interactions related to gut dysbiosis and bowel inflammation. This brief review highlights the potential links between vitamin D and gut health, emphasizing the role of vitamin D in microbiological and immunological mechanisms of inflammatory bowel diseases. A comprehensive literature search was carried out in PubMed and Google Scholar using combinations of keywords "vitamin D," "intestines," "gut microflora," "bowel inflammation". Only articles published in English and related to the study topic are included in the review. We discuss how vitamin D (a) modulates intestinal microbiome function, (b) controls antimicrobial peptide expression, and (c) has a protective effect on epithelial barriers in the gut mucosa. Vitamin D and its nuclear receptor (VDR) regulate intestinal barrier integrity, and control innate and adaptive immunity in the gut. Metabolites from the gut microbiota may also regulate expression of VDR, while vitamin D may influence the gut microbiota and exert anti-inflammatory and immune-modulating effects. The underlying mechanism of vitamin D in the pathogenesis of bowel diseases is not fully understood, but maintaining an optimal vitamin D status appears to be beneficial for gut health. Future studies will shed light on the molecular mechanisms through which vitamin D and VDR interactions affect intestinal mucosal immunity, pathogen invasion, symbiont colonization, and antimicrobial peptide expression.}, language = {en} } @article{RamoshabaHuismanLammertynetal.2020, author = {Ramoshaba, Nthai E. and Huisman, Hugo W. and Lammertyn, Leandi and Kotliar, Konstantin and Schutte, Aletta E. and Smith, Wayne}, title = {Retinal microvasculature and masked hypertension in young adults: the African-PREDICT study}, series = {Hypertension Research}, journal = {Hypertension Research}, number = {43}, publisher = {Springer Nature}, address = {Osaka}, issn = {1348-4214}, doi = {10.1038/s41440-020-0487-0}, pages = {1231 -- 1238}, year = {2020}, abstract = {Masked hypertension is known to induce microvascular complications. However, it is unclear whether early microvascular changes are already occurring in young, otherwise healthy adults. We therefore investigated whether retinal microvascular calibers and acute responses to a flicker stimulus are related to masked hypertension. We used the baseline data of 889 participants aged 20-30 years who were taking part in the African Prospective study on the Early Detection and Identification of Cardiovascular Disease and Hypertension. Clinic and 24-h ambulatory blood pressure were measured. The central retinal artery equivalent (CRAE) and central retinal vein equivalent were calculated from fundus images, and retinal vessel dilation was determined in response to flicker light-induced provocation. A smaller CRAE was observed in those with masked hypertension vs. those with normotension (157.1 vs. 161.2 measuring units, P < 0.001). In forward multivariable-adjusted regression analysis, only CRAE was negatively related to masked hypertension [adjusted R² = 0.267, β = -0.097 (95\% CI = -0.165; -0.029), P = 0.005], but other retinal microvascular parameters were not associated with masked hypertension. In multivariable logistic regression analyses, masked hypertension [OR = 2.333, (95\% CI = 1.316; 4.241), P = 0.004] was associated with a narrower CRAE. In young healthy adults, masked hypertension was associated with retinal arteriolar narrowing, thereby reflecting early microvascular alterations known to predict cardiovascular outcomes in later life.}, language = {en} } @article{AkimbekovQiaoDigeletal.2020, author = {Akimbekov, Nuraly and Qiao, Xiaohui and Digel, Ilya and Abdieva, Gulzhamal and Ualieva, Perizat and Zhubanova, Azhar}, title = {The effect of leonardite-derived amendments on soil microbiome structure and potato yield}, series = {Agriculture}, volume = {10}, journal = {Agriculture}, number = {Art. 147}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/agriculture10050147}, pages = {1 -- 17}, year = {2020}, abstract = {Humic substances originating from various organic matters can ameliorate soil properties, stimulate plant growth, and improve nutrient uptake. Due to the low calorific heating value, leonardite is rather unsuitable as fuel. However, it may serve as a potential source of humic substances. This study was aimed at characterizing the leonardite-based soil amendments and examining the effect of their application on the soil microbial community, as well as on potato growth and tuber yield. A high yield (71.1\%) of humic acid (LHA) from leonardite has been demonstrated. Parental leonardite (PL) and LHA were applied to soil prior to potato cultivation. The 16S rRNA sequencing of soil samples revealed distinct relationships between microbial community composition and the application of leonardite-based soil amendments. Potato tubers were planted in pots in greenhouse conditions. The tubers were harvested at the mature stage for the determination of growth and yield parameters. The results demonstrated that the LHA treatments had a significant effect on increasing potato growth (54.9\%) and tuber yield (66.4\%) when compared to the control. The findings highlight the importance of amending leonardite-based humic products for maintaining the biogeochemical stability of soils, for keeping their healthy microbial community structure, and for increasing the agronomic productivity of potato plants.}, language = {en} } @article{DachwaldUlamecPostbergetal.2020, author = {Dachwald, Bernd and Ulamec, Stephan and Postberg, Frank and Sohl, Frank and Vera, Jean-Pierre de and Christoph, Waldmann and Lorenz, Ralph D. and Hellard, Hugo and Biele, Jens and Rettberg, Petra}, title = {Key technologies and instrumentation for subsurface exploration of ocean worlds}, series = {Space Science Reviews}, volume = {216}, journal = {Space Science Reviews}, number = {Art. 83}, publisher = {Springer}, address = {Dordrecht}, issn = {1572-9672}, doi = {10.1007/s11214-020-00707-5}, pages = {45}, year = {2020}, abstract = {In this chapter, the key technologies and the instrumentation required for the subsurface exploration of ocean worlds are discussed. The focus is laid on Jupiter's moon Europa and Saturn's moon Enceladus because they have the highest potential for such missions in the near future. The exploration of their oceans requires landing on the surface, penetrating the thick ice shell with an ice-penetrating probe, and probably diving with an underwater vehicle through dozens of kilometers of water to the ocean floor, to have the chance to find life, if it exists. Technologically, such missions are extremely challenging. The required key technologies include power generation, communications, pressure resistance, radiation hardness, corrosion protection, navigation, miniaturization, autonomy, and sterilization and cleaning. Simpler mission concepts involve impactors and penetrators or - in the case of Enceladus - plume-fly-through missions.}, language = {en} } @article{HeinkeKnickerAlbracht2020, author = {Heinke, Lars N. and Knicker, Axel J. and Albracht, Kirsten}, title = {Increased shoulder muscle stretch reflex elicitability in supine subject posture}, series = {Isokinetics and Exercise Science}, volume = {28}, journal = {Isokinetics and Exercise Science}, number = {2}, publisher = {IOS Press}, address = {Amsterdam}, issn = {1878-5913}, doi = {10.3233/IES-192219}, pages = {139 -- 146}, year = {2020}, abstract = {BACKGROUND: Muscle stretch reflexes are widely used to examine neural muscle function. The knowledge of reflex response in muscles crossing the shoulder is limited. OBJECTIVE: To quantify reflex modulation according to various subject postures and different procedures of muscle pre-activation steering. METHODS: Thirteen healthy male participants performed two sets of external shoulder rotation stretches in various positions and with different procedures of muscle pre-activation steering on an isokinetic dynamometer over a range of two different pre-activation levels. All stretches were applied with a dynamometer acceleration of 104∘/s2 and a velocity of 150∘/s. Electromyographical response was measured via sEMG. RESULTS: Consistent reflexive response was observed in all tested muscles in all experimental conditions. The reflex elicitation rate revealed a significant muscle main effect (F (5,288) = 2.358, ρ= 0.040; η2= 0.039; f= 0.637) and a significant test condition main effect (F (1,288) = 5.884, ρ= 0.016; η2= 0.020; f= 0.143). Reflex latency revealed a significant muscle pre-activation level main effect (F (1,274) = 5.008, ρ= 0.026; η2= 0.018; f= 0.469). CONCLUSION: Muscular reflexive response was more consistent in the primary internal rotators of the shoulder. Supine posture in combination with visual feedback of muscle pre-activation level enhanced the reflex elicitation rate.}, language = {en} } @article{HeinEubanksHibberdetal.2020, author = {Hein, Andreas M. and Eubanks, T. Marshall and Hibberd, Adam and Fries, Dan and Schneider, Jean and Lingam, Manasvi and Kennedy, Robert and Perakis, Nikolaos and Dachwald, Bernd and Kervella, Pierre}, title = {Interstellar Now! Missions to and sample returns from nearby interstellar objects}, publisher = {Elsevier}, address = {Amsterdam}, pages = {1 -- 8}, year = {2020}, abstract = {The recently discovered first high velocity hyperbolic objects passing through the Solar System, 1I/'Oumuamua and 2I/Borisov, have raised the question about near term missions to Interstellar Objects. In situ spacecraft exploration of these objects will allow the direct determination of both their structure and their chemical and isotopic composition, enabling an entirely new way of studying small bodies from outside our solar system. In this paper, we map various Interstellar Object classes to mission types, demonstrating that missions to a range of Interstellar Object classes are feasible, using existing or near-term technology. We describe flyby, rendezvous and sample return missions to interstellar objects, showing various ways to explore these bodies characterizing their surface, dynamics, structure and composition. Interstellar objects likely formed very far from the solar system in both time and space; their direct exploration will constrain their formation and history, situating them within the dynamical and chemical evolution of the Galaxy. These mission types also provide the opportunity to explore solar system bodies and perform measurements in the far outer solar system.}, language = {en} } @article{TranStaat2021, author = {Tran, Ngoc Trinh and Staat, Manfred}, title = {Direct plastic structural design under random strength and random load by chance constrained programming}, series = {European Journal of Mechanics - A/Solids}, volume = {85}, journal = {European Journal of Mechanics - A/Solids}, number = {Article 104106}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0997-7538}, doi = {10.1016/j.euromechsol.2020.104106}, year = {2021}, 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{SeefeldtDachwald2021, author = {Seefeldt, Patric and Dachwald, Bernd}, title = {Temperature increase on folded solar sail membranes}, series = {Advances in Space Research}, volume = {67}, journal = {Advances in Space Research}, number = {9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, doi = {10.1016/j.asr.2020.09.026}, pages = {2688 -- 2695}, year = {2021}, language = {en} } @article{AlexyukBogoyavlenskiyAlexyuketal.2021, author = {Alexyuk, Madina and Bogoyavlenskiy, Andrey and Alexyuk, Pavel and Moldakhanov, Yergali and Berezin, Vladimir and Digel, Ilya}, title = {Epipelagic microbiome of the Small Aral Sea: Metagenomic structure and ecological diversity}, series = {MicrobiologyOpen}, volume = {10}, journal = {MicrobiologyOpen}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2045-8827}, doi = {10.1002/mbo3.1142}, pages = {1 -- 10}, year = {2021}, abstract = {Microbial diversity studies regarding the aquatic communities that experienced or are experiencing environmental problems are essential for the comprehension of the remediation dynamics. In this pilot study, we present data on the phylogenetic and ecological structure of microorganisms from epipelagic water samples collected in the Small Aral Sea (SAS). The raw data were generated by massive parallel sequencing using the shotgun approach. As expected, most of the identified DNA sequences belonged to Terrabacteria and Actinobacteria (40\% and 37\% of the total reads, respectively). The occurrence of Deinococcus-Thermus, Armatimonadetes, Chloroflexi in the epipelagic SAS waters was less anticipated. Surprising was also the detection of sequences, which are characteristic for strict anaerobes—Ignavibacteria, hydrogen-oxidizing bacteria, and archaeal methanogenic species. We suppose that the observed very broad range of phylogenetic and ecological features displayed by the SAS reads demonstrates a more intensive mixing of water masses originating from diverse ecological niches of the Aral-Syr Darya River basin than presumed before.}, language = {en} } @article{HeinkeKnickerAlbracht2021, author = {Heinke, Lars N. and Knicker, Axel J. and Albracht, Kirsten}, title = {Test-retest reliability of the internal shoulder rotator muscles' stretch reflex in healthy men}, series = {Journal of Electromyography and Kinesiology}, volume = {62}, journal = {Journal of Electromyography and Kinesiology}, number = {Article 102611}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1050-6411}, doi = {10.1016/j.jelekin.2021.102611}, year = {2021}, abstract = {Until now the reproducibility of the short latency stretch reflex of the internal rotator muscles of the glenohumeral joint has not been identified. Twenty-three healthy male participants performed three sets of external shoulder rotation stretches with various pre-activation levels on two different dates of measurement to assess test-retest reliability. All stretches were applied with a dynamometer acceleration of 104°/s2 and a velocity of 150°/s. Electromyographical response was measured via surface EMG. Reflex latencies showed a pre-activation effect (ƞ2 = 0,355). ICC ranged from 0,735 to 0,909 indicating an overall "good" relative reliability. SRD 95\% lay between ±7,0 to ±12,3 ms.. The reflex gain showed overall poor test-retest reproducibility. The chosen methodological approach presented a suitable test protocol for shoulder muscles stretch reflex latency evaluation. A proof-of-concept study to validate the presented methodical approach in shoulder involvement including subjects with clinically relevant conditions is recommended.}, language = {en} } @article{TemizArtmannKurulgandemirciFıratetal.2021, author = {Temiz Artmann, Ayseg{\"u}l and Kurulgan demirci, Eylem and F{\i}rat, Ipek Seda and Oflaz, Hakan and Artmann, Gerhard}, title = {Recombinant activated protein C (rhAPC) affects lipopolysaccharide-induced mechanical compliance changes and beat frequency of mESC-derived cardiomyocyte monolayers}, series = {SHOCK}, journal = {SHOCK}, publisher = {Wolters Kluwer}, address = {K{\"o}ln}, issn = {1540-0514}, doi = {10.1097/SHK.0000000000001845}, year = {2021}, language = {en} }