TY  - GEN
A1  - Topcu, Murat
A1  - Madabhushi, Gopal Santana Phani
A1  - Staat, Manfred
T1  - Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster
N2  - Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster for an elastic stress transfer between matrix and fibres having a variable radius.
KW  - Natural fibres
KW  - Polymer-matrix composites
KW  - Biocomposites
KW  - Stress concentrations
KW  - Finite element analysis (FEA)
Y1  - 2022
U6  - https://doi.org/10.6084/m9.figshare.19333295.v2
ER  - 
TY  - JOUR
A1  - Thiebes, Anja Lena
A1  - Klein, Sarah
A1  - Zingsheim, Jonas
A1  - Möller, Georg H.
A1  - Gürzing, Stefanie
A1  - Reddemann, Manuel A.
A1  - Behbahani, Mehdi
A1  - Cornelissen, Christian G.
T1  - Effervescent atomizer as novel cell spray technology to decrease the gas-to-liquid ratio
JF  - pharmaceutics
N2  - Cell spraying has become a feasible application method for cell therapy and tissue engineering approaches. Different devices have been used with varying success. Often, twin-fluid atomizers are used, which require a high gas velocity for optimal aerosolization characteristics. To decrease the amount and velocity of required air, a custom-made atomizer was designed based on the effervescent principle. Different designs were evaluated regarding spray characteristics and their influence on human adipose-derived mesenchymal stromal cells. The arithmetic mean diameters of the droplets were 15.4–33.5 µm with decreasing diameters for increasing gas-to-liquid ratios. The survival rate was >90% of the control for the lowest gas-to-liquid ratio. For higher ratios, cell survival decreased to approximately 50%. Further experiments were performed with the design, which had shown the highest survival rates. After seven days, no significant differences in metabolic activity were observed. The apoptosis rates were not influenced by aerosolization, while high gas-to-liquid ratios caused increased necrosis levels. Tri-lineage differentiation potential into adipocytes, chondrocytes, and osteoblasts was not negatively influenced by aerosolization. Thus, the effervescent aerosolization principle was proven suitable for cell applications requiring reduced amounts of supplied air. This is the first time an effervescent atomizer was used for cell processing.
KW  - tri-lineage differentiation
KW  - survival
KW  - twin-fluid atomizer
KW  - adipose-derived stromal cells (ASCs)
KW  - cell atomization
KW  - cell aerosolization
Y1  - 2022
U6  - https://doi.org/10.3390/pharmaceutics14112421
N1  - This article belongs to the Special Issue "Stromal, Stem, Signaling Cells: The Multiple Roles and Applications of Mesenchymal Cells"
VL  - 14
IS  - 11
PB  - MDPI
CY  - Basel
ER  - 
TY  - BOOK
A1  - Laack, Walter van
T1  - Greater Than the Entire Universe
Y1  - 2022
SN  - 978-3-936624-52-6
PB  - van Laack GmbH
CY  - Aachen
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Tran, Ngoc Trinh
T1  - Strain based brittle failure criteria for rocks
T2  - Proceedings of (NACOME2022) The 11th National Conference on Mechanics, Vol. 1. Solid Mechanics, Rock Mechanics, Artificial Intelligence, Teaching and Training
N2  - When confining pressure is low or absent, extensional fractures are typical, with fractures occurring on unloaded planes in rock. These “paradox” fractures 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. But this criterion makes unrealistic strength predictions in biaxial compression and tension. A new extension strain criterion overcomes this limitation by adding a weighted principal shear component. The 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 failure modes, which are unexpected in the 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. 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 P. Examples show that the enriched extension strain criterion predicts much lower volumes of damaged rock mass compared to the simple extension strain criterion.
KW  - Extension fracture
KW  - Extension strain criterion
KW  - Mohr–Coulomb criterion
KW  - Evolution of damage
Y1  - 2023
SN  - 978-604-357-084-7
N1  - 11th National Conference on Mechanics (NACOME 2022), December 2-3, 2022, VNU University of Engineering and Technology, Hanoi, Vietnam
SP  - 500
EP  - 509
PB  - Nha xuat ban Khoa hoc tu nhien va Cong nghe (Verlag Naturwissenschaft und Technik)
CY  - Hanoi
ER  - 
TY  - CHAP
A1  - Gaigall, Daniel
T1  - On Consistent Hypothesis Testing In General Hilbert Spaces
T2  - Proceedings of the 4th International Conference on Statistics: Theory and Applications (ICSTA’22)
N2  - Inference on the basis of high-dimensional and functional data are two topics which are discussed frequently in the current statistical literature. A possibility to include both topics in a single approach is working on a very general space for the underlying observations, such as a separable Hilbert space. We propose a general method for consistently hypothesis testing on the basis of random variables with values in separable Hilbert spaces. We avoid concerns with the curse of dimensionality due to a projection idea. We apply well-known test statistics from nonparametric inference to the projected data and integrate over all projections from a specific set and with respect to suitable probability measures. In contrast to classical methods, which are applicable for real-valued random variables or random vectors of dimensions lower than the sample size, the tests can be applied to random vectors of dimensions larger than the sample size or even to functional and high-dimensional data. In general, resampling procedures such as bootstrap or permutation are suitable to determine critical values. The idea can be extended to the case of incomplete observations. Moreover, we develop an efficient algorithm for implementing the method. Examples are given for testing goodness-of-fit in a one-sample situation in [1] or for testing marginal homogeneity on the basis of a paired sample in [2]. Here, the test statistics in use can be seen as generalizations of the well-known Cramérvon-Mises test statistics in the one-sample and two-samples case. The treatment of other testing problems is possible as well. By using the theory of U-statistics, for instance, asymptotic null distributions of the test statistics are obtained as the sample size tends to infinity. Standard continuity assumptions ensure the asymptotic exactness of the tests under the null hypothesis and that the tests detect any alternative in the limit. Simulation studies demonstrate size and power of the tests in the finite sample case, confirm the theoretical findings, and are used for the comparison with concurring procedures. A possible application of the general approach is inference for stock market returns, also in high data frequencies. In the field of empirical finance, statistical inference of stock market prices usually takes place on the basis of related log-returns as data. In the classical models for stock prices, i.e., the exponential Lévy model, Black-Scholes model, and Merton model, properties such as independence and stationarity of the increments ensure an independent and identically structure of the data. Specific trends during certain periods of the stock price processes can cause complications in this regard. In fact, our approach can compensate those effects by the treatment of the log-returns as random vectors or even as functional data.
Y1  - 2022
U6  - https://doi.org/10.11159/icsta22.157
N1  - 4th International Conference on Statistics: Theory and Applications (ICSTA’22), Prague, Czech Republic – July 28- 30
SP  - Paper No. 157
PB  - Avestia Publishing
CY  - Orléans, Kanada
ER  - 
TY  - INPR
A1  - Ringers, Christa
A1  - Bialonski, Stephan
A1  - Solovev, Anton
A1  - Hansen, Jan N.
A1  - Ege, Mert
A1  - Friedrich, Benjamin M.
A1  - Jurisch-Yaksi, Nathalie
T1  - Preprint: Local synchronization of cilia and tissue-scale cilia alignment are sufficient for global metachronal waves
T2  - bioRxiv
N2  - Motile cilia are hair-like cell extensions present in multiple organs of the body. How cilia coordinate their regular beat in multiciliated epithelia to move fluids remains insufficiently understood, particularly due to lack of rigorous quantification. We combine here experiments, novel analysis tools, and theory to address this knowledge gap. We investigate collective dynamics of cilia in the zebrafish nose, due to its conserved properties with other ciliated tissues and its superior accessibility for non-invasive imaging. We revealed that cilia are synchronized only locally and that the size of local synchronization domains increases with the viscosity of the surrounding medium. Despite the fact that synchronization is local only, we observed global patterns of traveling metachronal waves across the multiciliated epithelium. Intriguingly, these global wave direction patterns are conserved across individual fish, but different for left and right nose, unveiling a chiral asymmetry of metachronal coordination. To understand the implications of synchronization for fluid pumping, we used a computational model of a regular array of cilia. We found that local metachronal synchronization prevents steric collisions and improves fluid pumping in dense cilia carpets, but hardly affects the direction of fluid flow. In conclusion, we show that local synchronization together with tissue-scale cilia alignment are sufficient to generate metachronal wave patterns in multiciliated epithelia, which enhance their physiological function of fluid pumping.
Y1  - 2021
U6  - https://doi.org/10.1101/2021.11.23.469646
N1  - Veröffentlicht in eLife 12:e77701 (https://doi.org/10.7554/eLife.77701).
ER  - 
TY  - JOUR
A1  - Akimbekov, Nuraly S.
A1  - Digel, Ilya
A1  - Abdieva, Gulzhamal
A1  - Ualieva, Perizat
A1  - Tastambek, Kuanysh
T1  - Lignite biosolubilization and bioconversion by Bacillus sp.: the collation of analytical data
JF  - Biofuels
N2  - The vast metabolic potential of microbes in brown coal (lignite) processing and utilization can greatly contribute to innovative approaches to sustainable production of high-value products from coal. In this study, the multi-faceted and complex coal biosolubilization process by Bacillus sp. RKB 7 isolate from the Kazakhstan coal-mining soil is reported, and the derived products are characterized. Lignite solubilization tests performed for surface and suspension cultures testify to the formation of numerous soluble lignite-derived substances. Almost 24% of crude lignite (5% w/v) was solubilized within 14 days under slightly alkaline conditions (pH 8.2). FTIR analysis revealed various functional groups in the obtained biosolubilization products. Analyses of the lignite-derived humic products by UV-Vis and fluorescence spectrometry as well as elemental analysis yielded compatible results indicating the emerging products had a lower molecular weight and degree of aromaticity. Furthermore, XRD and SEM analyses were used to evaluate the biosolubilization processes from mineralogical and microscopic points of view. The findings not only contribute to a deeper understanding of microbe–mineral interactions in coal environments, but also contribute to knowledge of coal biosolubilization and bioconversion with regard to sustainable production of humic substances. The detailed and comprehensive analyses demonstrate the huge biotechnological potential of Bacillus sp. for agricultural productivity and environmental health.
KW  - humic acid
KW  - Bacillus sp
KW  - lignite
KW  - Biosolubilization
Y1  - 2021
SN  - 1759-7277
VL  - 12
IS  - 3
SP  - 247
EP  - 258
PB  - Taylor & Francis
CY  - London
ER  - 
TY  - JOUR
A1  - Hunker, Jan L.
A1  - Gossmann, Matthias
A1  - Raman, Aravind Hariharan
A1  - Linder, Peter
T1  - Artificial neural networks in cardiac safety assessment: Classification of chemotherapeutic compound effects on hiPSC-derived cardiomyocyte contractility
JF  - Journal of Pharmacological and Toxicological Methods
Y1  - 2021
U6  - https://doi.org/10.1016/j.vascn.2021.107044
SN  - 1056-8719
VL  - 111
IS  - Article number 107044
PB  - Elsevier
CY  - New York
ER  - 
TY  - JOUR
A1  - Jablonski, Melanie
A1  - Münstermann, Felix
A1  - Nork, Jasmina
A1  - Molinnus, Denise
A1  - Muschallik, Lukas
A1  - Bongaerts, Johannes
A1  - Wagner, Torsten
A1  - Keusgen, Michael
A1  - Siegert, Petra
A1  - Schöning, Michael Josef
T1  - Capacitive field‐effect biosensor applied for the detection of acetoin in alcoholic beverages and fermentation broths
JF  - physica status solidi (a) applications and materials science
N2  - An acetoin biosensor based on a capacitive electrolyte–insulator–semiconductor (EIS) structure modified with the enzyme acetoin reductase, also known as butane-2,3-diol dehydrogenase (Bacillus clausii DSM 8716ᵀ), is applied for acetoin detection in beer, red wine, and fermentation broth samples for the first time. The EIS sensor consists of an Al/p-Si/SiO₂/Ta₂O₅ layer structure with immobilized acetoin reductase on top of the Ta₂O₅ transducer layer by means of crosslinking via glutaraldehyde. The unmodified and enzyme-modified sensors are electrochemically characterized by means of leakage current, capacitance–voltage, and constant capacitance methods, respectively.
KW  - acetoin
KW  - acetoin reductase
KW  - alcoholic beverages
KW  - biosensors
KW  - capacitive field-effect sensors
Y1  - 2021
U6  - https://doi.org/10.1002/pssa.202000765
SN  - 1862-6319
N1  - Corresponding author: Melanie Jablonski
VL  - 218
IS  - 13
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Tran, Ngoc Trinh
A1  - Staat, Manfred
T1  - FEM shakedown analysis of Kirchhoff-Love plates under uncertainty of strength
T2  - Proceedings of UNCECOMP 2021
N2  - A new formulation to calculate the shakedown limit load of Kirchhoff plates under stochastic conditions of strength is developed. Direct structural reliability design by chance con-strained programming is based on the prescribed failure probabilities, which is an effective approach of stochastic programming if it can be formulated as an equivalent deterministic optimization problem. We restrict uncertainty to strength, the loading is still deterministic. A new formulation is derived in case of random strength with lognormal distribution. Upper bound and lower bound shakedown load factors are calculated simultaneously by a dual algorithm.
Y1  - 2021
SN  - 978-618-85072-6-5
U6  - https://doi.org/10.7712/120221.8041.19047
N1  - UNCECOMP 2021, 4th International Conference on Uncertainty Quantification in Computational Sciences and Engineering, streamed from Athens, Greece, 28–30 June 2021.
SP  - 323
EP  - 338
ER  - 
TY  - JOUR
A1  - Hackl, Michael
A1  - Nacov, Julia
A1  - Kammerlohr, Sandra
A1  - Staat, Manfred
A1  - Buess, Eduard
A1  - Leschinger, Tim
A1  - Müller, Lars P.
A1  - Wegmann, Kilian
T1  - Intratendinous Strain Variations of the Supraspinatus Tendon Depending on Repair Technique: A Biomechanical Analysis Regarding the Cause of Medial Cuff Failure
JF  - The American Journal of Sports Medicine
Y1  - 2021
U6  - https://doi.org/10.1177/03635465211006138
SN  - 1552-3365
SN  - 0363-5465
VL  - 49
IS  - 7
SP  - 1847
EP  - 1853
PB  - Sage
CY  - London
ER  - 
TY  - JOUR
A1  - Tran, Ngoc Trinh
A1  - Staat, Manfred
T1  - Direct plastic structural design under random strength and random load by chance constrained programming
JF  - European Journal of Mechanics - A/Solids
Y1  - 2021
U6  - https://doi.org/10.1016/j.euromechsol.2020.104106
SN  - 0997-7538
VL  - 85
IS  - Article 104106
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hugenroth, Kristin
A1  - Borchardt, Ralf
A1  - Ritter, Philine
A1  - Groß‑Hardt, Sascha
A1  - Meyns, Bart
A1  - Verbelen, Tom
A1  - Steinseifer, Ulrich
A1  - Kaufmann, Tim A. S.
A1  - Engelmann, Ulrich M.
T1  - Optimizing cerebral perfusion and hemodynamics during cardiopulmonary bypass through cannula design combining in silico, in vitro and in vivo input
JF  - Scientific Reports
N2  - Cardiopulmonary bypass (CPB) is a standard technique for cardiac surgery, but comes with the risk of severe neurological complications (e.g. stroke) caused by embolisms and/or reduced cerebral perfusion. We report on an aortic cannula prototype design (optiCAN) with helical outflow and jet-splitting dispersion tip that could reduce the risk of embolic events and restores cerebral perfusion to 97.5% of physiological flow during CPB in vivo, whereas a commercial curved-tip cannula yields 74.6%. In further in vitro comparison, pressure loss and hemolysis parameters of optiCAN remain unaffected. Results are reproducibly confirmed in silico for an exemplary human aortic anatomy via computational fluid dynamics (CFD) simulations. Based on CFD simulations, we firstly show that optiCAN design improves aortic root washout, which reduces the risk of thromboembolism. Secondly, we identify regions of the aortic intima with increased risk of plaque release by correlating areas of enhanced plaque growth and high wall shear stresses (WSS). From this we propose another easy-to-manufacture cannula design (opti2CAN) that decreases areas burdened by high WSS, while preserving physiological cerebral flow and favorable hemodynamics. With this novel cannula design, we propose a cannulation option to reduce neurological complications and the prevalence of stroke in high-risk patients after CPB.
Y1  - 2021
U6  - https://doi.org/10.1038/s41598-021-96397-2
SN  - 2045-2322
VL  - 11
IS  - Art. No. 16800
SP  - 1
EP  - 12
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Brockhaus, Moritz K.
A1  - Behbahani, Mehdi
A1  - Muris, Farina
A1  - Jansen, Sebastian V.
A1  - Schmitz- Rode, Thomas
A1  - Steinseifer, Ulrich
A1  - Clauser, Johanna C.
T1  - In vitro thrombogenicity testing of pulsatile mechanical circulatory support systems: Design and proof-of-concept
JF  - Artificial Organs
N2  - Thrombogenic complications are a main issue in mechanical circulatory support (MCS). There is no validated in vitro method available to quantitatively assess the thrombogenic performance of pulsatile MCS devices under realistic hemodynamic conditions. The aim of this study is to propose a method to evaluate the thrombogenic potential of new designs without the use of complex in-vivo trials. This study presents a novel in vitro method for reproducible thrombogenicity testing of pulsatile MCS systems using low molecular weight heparinized porcine blood. Blood parameters are continuously measured with full blood thromboelastometry (ROTEM; EXTEM, FIBTEM and a custom-made analysis HEPNATEM). Thrombus formation is optically observed after four hours of testing. The results of three experiments are presented each with two parallel loops. The area of thrombus formation inside the MCS device was reproducible. The implantation of a filter inside the loop catches embolizing thrombi without a measurable increase of platelet activation, allowing conclusions of the place of origin of thrombi inside the device. EXTEM and FIBTEM parameters such as clotting velocity (α) and maximum clot firmness (MCF) show a total decrease by around 6% with a characteristic kink after 180 minutes. HEPNATEM α and MCF rise within the first 180 minutes indicate a continuously increasing activation level of coagulation. After 180 minutes, the consumption of clotting factors prevails, resulting in a decrease of α and MCF. With the designed mock loop and the presented protocol we are able to identify thrombogenic hot spots inside a pulsatile pump and characterize their thrombogenic potential.
Y1  - 2021
U6  - https://doi.org/10.1111/aor.14046
SN  - 1525-1594
VL  - 45
IS  - 12
SP  - 1513
EP  - 1521
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Olderog, M.
A1  - Mohr, P.
A1  - Beging, Stefan
A1  - Tsoumpas, C.
A1  - Ziemons, Karl
T1  - Simulation study on the role of tissue-scattered events in improving sensitivity for a compact time of flight compton positron emission tomograph
T2  - 2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)
N2  - In positron emission tomography improving time, energy and spatial detector resolutions and using Compton kinematics introduces the possibility to reconstruct a radioactivity distribution image from scatter coincidences, thereby enhancing image quality. The number of single scattered coincidences alone is in the same order of magnitude as true coincidences. In this work, a compact Compton camera module based on monolithic scintillation material is investigated as a detector ring module. The detector interactions are simulated with Monte Carlo package GATE. The scattering angle inside the tissue is derived from the energy of the scattered photon, which results in a set of possible scattering trajectories or broken line of response. The Compton kinematics collimation reduces the number of solutions. Additionally, the time of flight information helps localize the position of the annihilation. One of the questions of this investigation is related to how the energy, spatial and temporal resolutions help confine the possible annihilation volume. A comparison of currently technically feasible detector resolutions (under laboratory conditions) demonstrates the influence on this annihilation volume and shows that energy and coincidence time resolution have a significant impact. An enhancement of the latter from 400 ps to 100 ps leads to a smaller annihilation volume of around 50%, while a change of the energy resolution in the absorber layer from 12% to 4.5% results in a reduction of 60%. The inclusion of single tissue-scattered data has the potential to increase the sensitivity of a scanner by a factor of 2 to 3 times. The concept can be further optimized and extended for multiple scatter coincidences and subsequently validated by a reconstruction algorithm.
Y1  - 2021
SN  - 978-1-7281-7693-2
U6  - https://doi.org/10.1109/NSS/MIC42677.2020.9507901
N1  - 2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 31 Oct.-7 Nov. 2020, Boston, MA, USA
PB  - IEEE
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - Grundlach, Michael
A1  - Baumann, Martin
A1  - Engelmann, Ulrich M.
ED  - Dössel, Olaf
T1  - How Multimodal Examinations Can Increase Sustainable Student Gain by Aligning Teaching and Assessment
JF  - Current Directions in Biomedical Engineering
N2  - Modern industry and multi-discipline projects require highly trained individuals with resilient science and engineering back-grounds. Graduates must be able to agilely apply excellent theoretical knowledge in their subject matter as well as essential practical “hands-on” knowledge of diverse working processes to solve complex problems. To meet these demands, university education follows the concept of Constructive Alignment and thus increasingly adopts the teaching of necessary practical skills to the actual industry requirements and assessment routines. However, a systematic approach to coherently align these three central teaching demands is strangely absent from current university curricula. We demonstrate the feasibility of implementing practical assessments in a regular theory-based examination, thus defining the term “blended assessment”. We assessed a course for natural science and engineering students pursuing a career in biomedical engineering, and evaluated the benefit of blended assessment exams for students and lecturers. Our controlled study assessed the physiological background of electrocardiograms (ECGs), the practical measurement of ECG curves, and their interpretation of basic pathologic alterations. To study on long time effects, students have been assessed on the topic twice with a time lag of 6 months. Our findings suggest a significant improvement in student gain with respect to practical skills and theoretical knowledge. The results of the reassessments support these outcomes. From the lecturers ́ point of view, blended assessment complements practical training courses while keeping organizational effort manageable. We consider blended assessment a viable tool for providing an improved student gain, industry-ready education format that should be evaluated and established further to prepare university graduates optimally for their future careers.
KW  - constructive alignment
KW  - examination
KW  - long-term retention
KW  - multimodal
KW  - practical learning
Y1  - 2021
SN  - 2364-5504
U6  - https://doi.org/10.1515/cdbme-2021-2019
VL  - 7
IS  - 7/2
SP  - 73
EP  - 76
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Oliveira, Danilo A.
A1  - Molinnus, Denise
A1  - Beging, Stefan
A1  - Siqueira Jr, José R.
A1  - Schöning, Michael Josef
T1  - Biosensor Based on Self-Assembled Films of Graphene Oxide and Polyaniline Using a Field-Effect Device Platform
JF  - physica status solidi (a) applications and materials science
N2  - A new functionalization method to modify capacitive electrolyte–insulator–semiconductor (EIS) structures with nanofilms is presented. Layers of polyallylamine hydrochloride (PAH) and graphene oxide (GO) with the compound polyaniline:poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PANI:PAAMPSA) are deposited onto a p-Si/SiO2 chip using the layer-by-layer technique (LbL). Two different enzymes (urease and penicillinase) are separately immobilized on top of a five-bilayer stack of the PAH:GO/PANI:PAAMPSA-modified EIS chip, forming a biosensor for detection of urea and penicillin, respectively. Electrochemical characterization is performed by constant capacitance (ConCap) measurements, and the film morphology is characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). An increase in the average sensitivity of the modified biosensors (EIS–nanofilm–enzyme) of around 15% is found in relation to sensors, only carrying the enzyme but without the nanofilm (EIS–enzyme). In this sense, the nanofilm acts as a stable bioreceptor onto the EIS chip improving the output signal in terms of sensitivity and stability.
KW  - capacitive electrolyte–insulator–semiconductor sensors
KW  - graphene oxide
KW  - layer-by-layer technique
KW  - nanomaterials
KW  - polyaniline
Y1  - 2021
U6  - https://doi.org/10.1002/pssa.202000747
SN  - 1862-6319
N1  - Corresponding author: José R. Siqueira Jr & Michael J. Schöning
VL  - 218
IS  - 13
SP  - 1
EP  - 9
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Welden, Rene
A1  - Nagamine Komesu, Cindy A.
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
T1  - Photoelectrochemical enzymatic penicillin biosensor: A proof-of-concept experiment
JF  - Electrochemical Science Advances
N2  - Photoelectrochemical (PEC) biosensors are a rather novel type of biosensors thatutilizelighttoprovideinformationaboutthecompositionofananalyte,enablinglight-controlled multi-analyte measurements. For enzymatic PEC biosensors,amperometric detection principles are already known in the literature. In con-trast, there is only a little information on H+-ion sensitive PEC biosensors. Inthis work, we demonstrate the detection of H+ions emerged by H+-generatingenzymes, exemplarily demonstrated with penicillinase as a model enzyme on atitanium dioxide photoanode. First, we describe the pH sensitivity of the sensorand study possible photoelectrocatalytic reactions with penicillin. Second, weshow the enzymatic PEC detection of penicillin.
KW  - enzymatic biosensor
KW  - penicillin
KW  - penicillinase
KW  - photoelectrochemistry
KW  - titanium dioxide photoanode
Y1  - 2021
U6  - https://doi.org/10.1002/elsa.202100131
SN  - 2698-5977
N1  - Corresponding author: Michael J. Schöning
VL  - 2
IS  - 4
SP  - 1
EP  - 5
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Richter, Charlotte
A1  - Braunstein, Bjoern
A1  - Staeudle, Benjamin
A1  - Attias, Julia
A1  - Suess, Alexander
A1  - Weber, Tobias
A1  - Mileva, Katya N.
A1  - Rittweger, Joern
A1  - Green, David A.
A1  - Albracht, Kirsten
T1  - Contractile behavior of the gastrocnemius medialis muscle during running in simulated hypogravity
JF  - npj Microgravity
N2  - Vigorous exercise countermeasures in microgravity can largely attenuate muscular degeneration, albeit the extent of applied loading is key for the extent of muscle wasting. Running on the International Space Station is usually performed with maximum loads of 70% body weight (0.7 g). However, it has not been investigated how the reduced musculoskeletal loading affects muscle and series elastic element dynamics, and thereby force and power generation. Therefore, this study examined the effects of running on the vertical treadmill facility, a ground-based analog, at simulated 0.7 g on gastrocnemius medialis contractile behavior. The results reveal that fascicle−series elastic element behavior differs between simulated hypogravity and 1 g running. Whilst shorter peak series elastic element lengths at simulated 0.7 g appear to be the result of lower muscular and gravitational forces acting on it, increased fascicle lengths and decreased velocities could not be anticipated, but may inform the development of optimized running training in hypogravity. However, whether the alterations in contractile behavior precipitate musculoskeletal degeneration warrants further study.
Y1  - 2021
U6  - https://doi.org/10.1038/s41526-021-00155-7
SN  - 2373-8065
N1  - Corresponding author: Charlotte Richter
VL  - 7
IS  - Article number: 32
PB  - Springer Nature
CY  - New York
ER  - 
TY  - CHAP
A1  - Mandekar, Swati
A1  - Jentsch, Lina
A1  - Lutz, Kai
A1  - Behbahani, Mehdi
A1  - Melnykowycz, Mark
T1  - Earable design analysis for sleep EEG measurements
T2  - UbiComp '21
N2  - Conventional EEG devices cannot be used in everyday life and hence, past decade research has been focused on Ear-EEG for mobile, at-home monitoring for various applications ranging from emotion detection to sleep monitoring. As the area available for electrode contact in the ear is limited, the electrode size and location play a vital role for an Ear-EEG system. In this investigation, we present a quantitative study of ear-electrodes with two electrode sizes at different locations in a wet and dry configuration. Electrode impedance scales inversely with size and ranges from 450 kΩ to 1.29 MΩ for dry and from 22 kΩ to 42 kΩ for wet contact at 10 Hz. For any size, the location in the ear canal with the lowest impedance is ELE (Left Ear Superior), presumably due to increased contact pressure caused by the outer-ear anatomy. The results can be used to optimize signal pickup and SNR for specific applications. We demonstrate this by recording sleep spindles during sleep onset with high quality (5.27 μVrms).
KW  - EEG
KW  - sensors
KW  - Impedance Spectroscopy
KW  - Sleep EEG
KW  - biopotential electrodes
Y1  - 2021
U6  - https://doi.org/10.1145/3460418.3479328
N1  - UbiComp '21: Adjunct Proceedings of the 2021 ACM International Joint Conference on Pervasive and Ubiquitous Computing and Proceedings of the 2021 ACM International Symposium on Wearable Computers, September 21–26, 2021, Virtual, USA
SP  - 171
EP  - 175
ER  -