TY - JOUR A1 - Valero, Daniel A1 - Bung, Daniel B. T1 - Artificial Neural Networks and pattern recognition for air-water flow velocity estimation using a single-tip optical fibre probe JF - Journal of Hydro-environment Research Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.jher.2017.08.004 SN - 1570-6443 VL - 19 IS - 3 SP - 150 EP - 159 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Valero, Daniel A1 - Bung, Daniel B. T1 - Reformulating self-aeration in hydraulic structures: Turbulent growth of free surface perturbations leading to air entrainment JF - International Journal of Multiphase Flow N2 - A new formulation for the prediction of free surface dynamics related to the turbulence occurring nearby is proposed. This formulation, altogether with a breakup criterion, can be used to compute the inception of self-aeration in high velocity flows like those occurring in hydraulic structures. Assuming a simple perturbation geometry, a kinematic and a non-linear momentum-based dynamic equation are formulated and forces acting on a control volume are approximated. Limiting steepness is proposed as an adequate breakup criterion. Role of the velocity fluctuations normal to the free surface is shown to be the main turbulence quantity related to self-aeration and the role of the scales contained in the turbulence spectrum are depicted. Surface tension force is integrated accounting for large displacements by using differential geometry for the curvature estimation. Gravity and pressure effects are also contemplated in the proposed formulation. The obtained equations can be numerically integrated for each wavelength, hence resulting in different growth rates and allowing computation of the free surface roughness wavelength distribution. Application to a prototype scale spillway (at the Aviemore dam) revealed that most unstable wavelength was close to the Taylor lengthscale. Amplitude distributions have been also obtained observing different scaling for perturbations stabilized by gravity or surface tension. The proposed theoretical framework represents a new conceptualization of self-aeration which explains the characteristic rough surface at the non-aerated region as well as other previous experimental observations which remained unresolved for several decades. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.ijmultiphaseflow.2017.12.011 SN - 0301-9322 VL - 100 SP - 127 EP - 142 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Laumann, Jörg A1 - Mainz, Stefan A1 - Krahwinkel, Manuel T1 - Traglastuntersuchungen an Koppelpfetten bei Biegung um die schwache Achse und Torsion JF - Stahlbau Y1 - 2017 U6 - http://dx.doi.org/10.1002/stab.201710544 SN - 0038-9145 VL - 86 IS - 11 SP - 1005 EP - 1016 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schäfer, Johannes A1 - Wilms, Konrad A1 - Schleser, Markus T1 - Aufmischungsarmes, dickschichtiges MSG-Auftragschweißen mit entkoppelter Zweidrahttechnik JF - Schweißen und Schneiden N2 - Für Auftragschweißaufgaben existiert eine Vielzahl an verfahrenstechnischen Prozessvarianten, die je nach Charakteristik und Anwendungsfall ausgewählt werden. Ein Nachteil der vorwiegend verwendeten Metall- Schutzgasschweißprozesse (MSG) für das Auftragschweißen ist durch die direkte Kopplung von Drahtvorschub zu Energieeintrag gegeben. Die vorgestellte Zweidraht-Prozessvariante kann durch die Ausbildung eines übertragenen und eines nicht-übertragenen Lichtbogens die elektrische Leistung beider Lichtbögen variieren und damit einen direkten Einfluss auf die Prozessgrößen Abschmelzleistung und Aufschmelzgrad nehmen. Im Speziellen besteht über die Entkopplung von Drahtvorschub zu Schweißstromstärke die Möglichkeit eines niederenergetischen Betriebs trotz hoher Drahtvorschubgeschwindigkeit. Damit lassen sich Aufschmelzgrade unter 2% umsetzen und Abschmelzleistungen bis zu 15 kg/h realisieren. Y1 - 2017 SN - 0036-7184 VL - 69 IS - 12 SP - 838 EP - 843 PB - DVS Verlag CY - Düsseldorf ER - TY - JOUR A1 - Reifenberg, Dirk A1 - Jörissen, Jörg A1 - Peters, David T1 - Ausgewählte Ergebnisse einer kooperativen Studie zu Hochschulwechsel und Studienabbruch JF - Qualität in der Wissenschaft (QiW) Y1 - 2015 SN - 1860-3041 VL - 9 IS - 3+4 SP - 99 EP - 105 PB - UVW Universitätsverlag Webler CY - Bielefeld ER - TY - JOUR A1 - Jörissen, Jörg A1 - Heger, Michael T1 - Zur Wirkung hochschuldidaktisch fundierter und in den Fachbereichen verankerter Lehrveranstaltungsevaluation JF - Qualität in der Wissenschaft (QiW) Y1 - 2014 SN - 1860-3041 VL - 8 IS - 2+3 SP - 70 EP - 80 PB - Universitätsverlag Webler CY - Bielefeld ER - TY - JOUR A1 - Bhattarai, Aroj A1 - Staat, Manfred T1 - Modelling of Soft Connective Tissues to Investigate Female Pelvic Floor Dysfunctions JF - Computational and Mathematical Methods in Medicine N2 - After menopause, decreased levels of estrogen and progesterone remodel the collagen of the soft tissues thereby reducing their stiffness. Stress urinary incontinence is associated with involuntary urine leakage due to pathological movement of the pelvic organs resulting from lax suspension system, fasciae, and ligaments. This study compares the changes in the orientation and position of the female pelvic organs due to weakened fasciae, ligaments, and their combined laxity. A mixture theory weighted by respective volume fraction of elastin-collagen fibre compound (5%), adipose tissue (85%), and smooth muscle (5%) is adopted to characterize the mechanical behaviour of the fascia. The load carrying response (other than the functional response to the pelvic organs) of each fascia component, pelvic organs, muscles, and ligaments are assumed to be isotropic, hyperelastic, and incompressible. Finite element simulations are conducted during Valsalva manoeuvre with weakened tissues modelled by reduced tissue stiffness. A significant dislocation of the urethrovesical junction is observed due to weakness of the fascia (13.89 mm) compared to the ligaments (5.47 mm). The dynamics of the pelvic floor observed in this study during Valsalva manoeuvre is associated with urethral-bladder hypermobility, greater levator plate angulation, and positive Q-tip test which are observed in incontinent females. Y1 - 2018 U6 - http://dx.doi.org/10.1155/2018/9518076 SN - 1748-6718 VL - 2018 IS - Article ID 9518076 SP - 1 EP - 16 PB - Hindawi CY - New York, NY ER - TY - JOUR A1 - Oberländer, Jan A1 - Mayer, Marlena A1 - Greeff, Anton A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Spore-based biosensor to monitor the microbicidal efficacy of gaseous hydrogen peroxide sterilization processes JF - Biosensors and Bioelectronics N2 - In this work, a spore-based biosensor is evaluated to monitor the microbicidal efficacy of sterilization processes applying gaseous hydrogen peroxide (H2O2). The sensor is based on interdigitated electrode structures (IDEs) that have been fabricated by means of thin-film technologies. Impedimetric measurements are applied to study the effect of sterilization process on spores of Bacillus atrophaeus. This resilient microorganism is commonly used in industry to proof the sterilization efficiency. The sensor measurements are accompanied by conventional microbiological challenge tests, as well as morphological characterizations with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The sensor measurements are correlated with the microbiological test routines. In both methods, namely the sensor-based and microbiological one, a tailing effect has been observed. The results are evaluated and discussed in a three-dimensional calibration plot demonstrating the sensor's suitability to enable a rapid process decision in terms of a successfully performed sterilization. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.bios.2017.12.045 SN - 0956-5663 VL - 104 SP - 87 EP - 94 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Moorkamp, Wilfried A1 - Peterson, Leif Arne A1 - Uibel, Thomas T1 - Mit guten Aussichten. Bericht über den Studiengang Holzingenieurwesen an der FH Aachen JF - Bauen mit Holz Y1 - 2016 SN - 0005-6545 N1 - gedruckte Zeitschrift in der Bereichsbibliothek Bayernallee IS - 5 SP - 33 EP - 36 PB - Rudolf Müller CY - Köln ER - TY - JOUR A1 - Uibel, Thomas T1 - Untersuchungen zum Spaltverhalten von Holzschrauben. Teil 1 JF - Bauen mit Holz Y1 - 2016 SN - 0005-6545 N1 - gedruckte Zeitschrift in der Bereichsbibliothek Bayernallee IS - 10 SP - 40 EP - 42 PB - Rudolf Müller CY - Köln ER - TY - JOUR A1 - Peterson, Leif Arne A1 - Röth, Thilo A1 - Uibel, Thomas T1 - Einsatz von Holzwerkstoffen in Fahrzeugstrukturen JF - Bauen mit Holz Y1 - 2017 SN - 0005-6545 N1 - gedruckt in der Bereichsbibliothek Bayernallee IS - 3 SP - 32 EP - 38 PB - Bruderverlag CY - Köln ER - TY - JOUR A1 - Rieke, Christian A1 - Stollenwerk, Dominik A1 - Dahmen, Markus A1 - Pieper, Martin T1 - Modeling and optimization of a biogas plant for a demand-driven energy supply JF - Energy N2 - Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process. This paper provides a new model of a biogas plant, which is as accurate as the standard ADM1 model. The advantage compared to ADM1 is that it is based on only four parameters compared to 28. Applying this model, an optimization was installed, which allows a demand-driven supply by biogas plants. Finally the results are confirmed by several experiments and measurements with a real test plant. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.energy.2017.12.073 SN - 0360-5442 VL - 145 SP - 657 EP - 664 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wollert, Jörg T1 - Echtzeit-Ethernet - Basis für Industrie 4.0 JF - Design & Elektronik Y1 - 2017 SN - 0933-8667 N1 - Echtzeit für Industrie 4.0. - Teil 1 IS - 12 SP - 38 EP - 41 PB - WEKA-Fachmedien CY - Haar, München ER - TY - JOUR A1 - Reichert, Walter T1 - Berufseinstieg für Wirtschaftsingenieure - Bachelor oder Master? JF - Berufsstart Y1 - 2017 ER - TY - JOUR A1 - Pfaff, Raphael A1 - Enning, Manfred T1 - Die nachhaltige Alternative zum autonomen Lastwagen JF - Deine Bahn Y1 - 2017 IS - 10 SP - 22 EP - 26 ER - TY - JOUR A1 - Pfaff, Raphael T1 - Apps für den Güterwagen? Wie der Güterwagen 4.0 die effiziente Integration der Güterbahn in ERTMS ermöglicht JF - Ingenieurspiegel Y1 - 2017 IS - 2 SP - 1 EP - 2 ER - TY - JOUR A1 - Pfaff, Raphael T1 - Einsatz von offenen Onlinekursen in der Eisenbahnlehre JF - Deine Bahn N2 - Eigene positive Erfahrungen mit Onlinekursen sowie die geringen Studierendenzahlen in der Präsenzlehre gaben den Anstoß zu einem Experiment mit einem offenen Onlinekurs auf der Plattform Udemy. Die Erfahrungen sowohl bei der Erstellung und als auch im Lehrbetrieb waren positiv und führten zu einer neuen Beschäftigung mit Inhalten und Lernenden, getrieben durch die Anforderungen der Lernplattform. Y1 - 2017 SN - 0948-7263 IS - 1 SP - 12 EP - 16 PB - Bahn-Fachverlag CY - Berlin ER - TY - JOUR A1 - Schiffer, Stefan A1 - Ferrein, Alexander T1 - Decision-Theoretic Planning with Fuzzy Notions in GOLOG JF - International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems N2 - In this paper we present an extension of the action language Golog that allows for using fuzzy notions in non-deterministic argument choices and the reward function in decision-theoretic planning. Often, in decision-theoretic planning, it is cumbersome to specify the set of values to pick from in the non-deterministic-choice-of-argument statement. Also, even for domain experts, it is not always easy to specify a reward function. Instead of providing a finite domain for values in the non-deterministic-choice-of-argument statement in Golog, we now allow for stating the argument domain by simply providing a formula over linguistic terms and fuzzy uents. In Golog’s forward-search DT planning algorithm, these formulas are evaluated in order to find the agent’s optimal policy. We illustrate this in the Diner Domain where the agent needs to calculate the optimal serving order. Y1 - 2016 U6 - http://dx.doi.org/10.1142/S0218488516400134 SN - 1793-6411 VL - 24 IS - Issue Suppl. 2 SP - 123 EP - 143 PB - World Scientific CY - Singapur ER - TY - JOUR A1 - Ferrein, Alexander A1 - Steinbauer, Gerald T1 - Looking back on 20 Years of RoboCup JF - KI - Künstliche Intelligenz Y1 - 2016 U6 - http://dx.doi.org/10.1007/s13218-016-0443-y SN - 1610-1987 VL - 30 IS - 3-4 SP - 321 EP - 323 PB - Springer CY - Berlin ER - TY - JOUR A1 - Steinbauer, Gerald A1 - Ferrein, Alexander T1 - 20 Years of RoboCup JF - KI - Künstliche Intelligenz Y1 - 2016 U6 - http://dx.doi.org/10.1007/s13218-016-0442-z SN - 1610-1987 VL - 30 IS - 3-4 SP - 221 EP - 224 PB - Springer CY - Berlin ER - TY - JOUR A1 - Ferrein, Alexander A1 - Steinbauer, Gerald T1 - The Interplay of Aldebaran and RoboCup JF - KI - Künstliche Intelligenz Y1 - 2016 U6 - http://dx.doi.org/10.1007/s13218-016-0440-1 SN - 1610-1987 VL - 30 IS - 3-4 SP - 325 EP - 326 PB - Springer CY - Berlin ER - TY - JOUR A1 - Niemueller, Tim A1 - Karras, Ulrich A1 - Ferrein, Alexander T1 - Meisterschaft der Maschinen: Die Industrial Logistic Liga JF - C´t Magazin für Computertechnik Y1 - 2017 IS - 26 ER - TY - JOUR A1 - Werkhausen, Amelie A1 - Albracht, Kirsten A1 - Cronin, Neil J. A1 - Meier, Rahel A1 - Mojsen-Moeller, Jens A1 - Seynnes, Olivier R. T1 - Modulation of muscle-tendon interaction in the human triceps surae during an energy dissipation task JF - Journal of Experimental Biology Y1 - 2017 U6 - http://dx.doi.org/10.1242/jeb.164111 SN - 0022-0949 VL - 220 IS - 22 SP - 4141 EP - 4149 ER - TY - JOUR A1 - Demmer, Julius K. A1 - Chowdhury, Nilanjan Pal A1 - Selmer, Thorsten A1 - Ermler, Ulrich A1 - Buckel, Wolfgang T1 - The semiquinone swing in the bifurcating electron transferring flavoprotein/butyryl-CoA dehydrogenase complex from Clostridium difficile JF - Nature Communications Y1 - 2017 U6 - http://dx.doi.org/10.1038/s41467-017-01746-3 SN - 2041-1723 N1 - Article number 1577 VL - 8 IS - 1 SP - 1 EP - 10 ER - TY - JOUR A1 - Breuer, Lars A1 - Mang, Thomas A1 - Schöning, Michael Josef A1 - Thoelen, Ronald A1 - Wagner, Torsten T1 - Investigation of the spatial resolution of a laser-based stimulation process for light-addressable hydrogels with incorporated graphene oxide by means of IR thermography JF - Sensors and Actuators A: Physical Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.sna.2017.11.031 SN - 0924-4247 VL - 268 SP - 126 EP - 132 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kotliar, Konstantin A1 - Hauser, Christine A1 - Ortner, Marion A1 - Muggenthaler, Claudia A1 - Diehl-Schmid, Janine A1 - Angermann, Susanne A1 - Hapfelmeier, Alexander A1 - Schmaderer, Christoph A1 - Grimmer, Timo T1 - Altered neurovascular coupling as measured by optical imaging: a biomarker for Alzheimer’s disease JF - Scientific Reports Y1 - 2017 U6 - http://dx.doi.org/10.1038/s41598-017-13349-5 SN - 2045-2322 N1 - Article 12906 VL - 7 IS - 1 SP - 1 EP - 11 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Ulber, Roland A1 - Tippkötter, Nils T1 - Nitratfreie Molke JF - Rundschau für Fleischhygiene und Lebensmittelüberwachung Y1 - 2009 IS - 4 SP - 150 EP - 152 ER - TY - JOUR A1 - Rietsch, Stefan H. G. A1 - Pfaffenrot, Viktor A1 - Bitz, Andreas A1 - Orzada, Stephan A1 - Brunheim, Sascha A1 - Lazik-Palm, Andrea A1 - Theysohn, Jens M. A1 - Ladd, Mark E. A1 - Quick, Harald H. A1 - Kraff, Oliver T1 - An 8-channel transceiver 7-channel receive RF coil setup for high SNR ultrahigh-field MRI of the shoulder at 7T JF - Medical Physics Y1 - 2017 U6 - http://dx.doi.org/10.1002/mp.12612 SN - 0094-2405 IS - Article in press PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Tippkötter, Nils A1 - Stückmann, Henning A1 - Kroll, Stephen A1 - Winkelmann, Gunda A1 - Noack, Udo A1 - Scheper, Thomas A1 - Ulber, Roland T1 - A semi-quantitative dipstick assay for microcystin JF - Analytical and Bioanalytical Chemistry N2 - An immunochromatographic lateral flow dipstick assay for the fast detection of microcystin-LR was developed. Colloid gold particles with diameters of 40 nm were used as red-colored antibody labels for the visual detection of the antigen. The new dipstick sensor is capable of detecting down to 5 µg·l−1 (ppb; total inversion of the color signal) or 1 ppb (observation of color grading) of microcystin-LR. The course of the labeling reaction was observed via spectrometric wave shifts caused by the change of particle size during the binding of antibodies. Different stabilizing reagents showed that especially bovine serum albumin (BSA) and casein increase the assays sensitivity and the conjugate stability. Performance of the dipsticks was quantified by pattern processing of capture zone CCD images. Storage stability of dipsticks and conjugate suspensions over 115 days under different conditions were monitored. The ready-to-use dipsticks were successfully tested with microcystin-LR-spiked samples of outdoor drinking- and salt water and applied to the tissue of microcystin-fed mussels. Y1 - 2009 U6 - http://dx.doi.org/10.1007/s00216-009-2750-8 SN - 1618-2650 VL - 394 IS - 3 SP - 863 EP - 869 PB - springer CY - Berlin ER - TY - JOUR A1 - Ulber, R. A1 - Tippkötter, Nils A1 - Buchholz, H. A1 - Demmer, W. A1 - Scheper, T. T1 - Innovative Verfahren in der Molkeaufarbeitung zur Gewinnung neuer Produkte JF - Deutsche Milchwirtschaft Y1 - 2008 SN - 0012-0480 VL - 59 IS - 19 SP - 704 EP - 706 ER - TY - JOUR A1 - Tippkötter, Nils A1 - Roikaew, W. A1 - Ulber, R. T1 - Nitrate removal from whey concentrate with biotechnological regeneration of the waste water JF - European dairy magazine : EDM Y1 - 2008 SN - 0936-6318 IS - 1 SP - 30 EP - 32 ER - TY - JOUR A1 - Tippkötter, Nils A1 - Roikaew, N. A1 - Ulber, R. T1 - Nitratentfernung aus Molkekonzentrat mit biotechnologischer Regeneration der Abwässer JF - Deutsche Milchwirtschaft Y1 - 2007 SN - 0012-0480 VL - 58 IS - 15 SP - 540 EP - 542 ER - TY - JOUR A1 - Balzer, Hermann A1 - Streit, Daniel A1 - Heinze, Marcel ED - Krause, Stefan T1 - Implikationen der Digitalisierung für den Finanzbereich der Unternehmung und das Rollenbild des CFO JF - Betriebswirtschaftliche Implikationen der digitalen Transformation. ZfbF - Schmalenbachs Zeitschrift für betriebswirtschaftliche Forschung, Sonderheft 72 Y1 - 2017 U6 - http://dx.doi.org/10.1007/978-3-658-18751-4_14 N1 - ZfbF - Schmalenbachs Zeitschrift für betriebswirtschaftliche Forschung. Sonderheft 72. Arbeitskreis Finanzierung der Schmalenbach-Gesellschaft e.V. IS - 72 SP - 267 EP - 283 PB - Springer CY - Berlin ER - TY - JOUR A1 - Orzada, Stephan A1 - Bitz, Andreas A1 - Johst, Sören A1 - Gratz, Marcel A1 - Völker, Maximilian N. A1 - Kraff, Oliver A1 - Abuelhaija, Ashraf A1 - Fiedler, Thomas M. A1 - Solbach, Klaus A1 - Quick, Harald H. A1 - Ladd, Mark E. T1 - Analysis of an integrated 8-Channel Tx/Rx body array for use as a body coil in 7-Tesla MRI JF - Frontiers in Physics Y1 - 2017 U6 - http://dx.doi.org/10.3389/fphy.2017.00017 SN - 2296-424X N1 - Article number 17 VL - 5 IS - Jun ER - TY - JOUR A1 - Garibaldi, F. A1 - Beging, Stefan A1 - Canese, R. A1 - Carpinelli, G. A1 - Clinthorne, N. A1 - Colilli, S. A1 - Cosentino, L. A1 - Finocchiaro, P. A1 - Giuliani, F. A1 - Gricia, M. A1 - Lucentini, M. A1 - Majewski, S. A1 - Monno, E. A1 - Musico, P. A1 - Santavenere, F. A1 - Tödter, J. A1 - Wegener, Hans-Peter A1 - Ziemons, Karl T1 - A novel TOF-PET MRI detector for diagnosis and follow up of the prostate cancer JF - European Physical Journal Plus Y1 - 2017 U6 - http://dx.doi.org/10.1140/epjp/i2017-11662-x SN - 2190-5444 VL - 132 IS - 9 PB - Springer CY - Berlin ER - TY - JOUR A1 - Srivastava, A. A1 - Chahar, V. A1 - Sharma, V. A1 - Sun, Y. A1 - Bol, R. A1 - Knolle, F. A1 - Schnug, E. A1 - Hoyler, Friedrich A1 - Naskar, N. A1 - Lahiri, S. A1 - Patnaik, R. T1 - Study of uranium toxicity using low-background gamma-ray spectrometry JF - Journal of Radioanalytical and Nuclear Chemistry Y1 - 2017 U6 - http://dx.doi.org/10.1007/s10967-017-5466-9 SN - 1588-2780 IS - Online first SP - 1 EP - 7 PB - Springer CY - Berlin ER - TY - JOUR A1 - Höttges, Jörg T1 - QKan - Management of drainage system data with QGIS JF - Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings Y1 - 2017 VL - 17 IS - Article 13 SP - 95 EP - 100 ER - TY - JOUR A1 - Seifarth, Volker A1 - Grosse, Joachim O. A1 - Grossmann, Matthias A1 - Janke, Heinz Peter A1 - Arndt, Patrick A1 - Koch, Sabine A1 - Epple, Matthias A1 - Artmann, Gerhard A1 - Temiz Artmann, Aysegül T1 - Mechanical induction of bi-directional orientation of primary porcine bladder smooth muscle cells in tubular fibrin-poly(vinylidene fluoride) scaffolds for ureteral and urethral repair using cyclic and focal balloon catheter stimulation JF - Journal of Biomaterials Applications Y1 - 2017 U6 - http://dx.doi.org/10.1177/0885328217723178 SN - 1530-8022 VL - 32 IS - 3 SP - 321 EP - 330 PB - Sage CY - London ER - TY - JOUR A1 - Albanna, Walid A1 - Lueke, Jan Niklas A1 - Sjapic, Volha A1 - Kotliar, Konstantin A1 - Hescheler, Jürgen A1 - Clusmann, Hans A1 - Sjapic, Sergej A1 - Alpdogan, Serdan A1 - Schneider, Toni A1 - Schubert, Gerrit Alexander A1 - Neumaier, Felix T1 - Electroretinographic Assessment of Inner Retinal Signaling in the Isolated and Superfused Murine Retina JF - Current Eye Research Y1 - 2017 U6 - http://dx.doi.org/10.1080/02713683.2017.1339807 SN - 1460-2202 IS - Article in press SP - 1 EP - 9 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Schopp, Christoph A1 - Doll, Timo A1 - Gräser, Ulrich A1 - Harzheim, Thomas A1 - Heuermann, Holger A1 - Kling, Rainer A1 - Marso, Michael T1 - Capacitively Coupled High-Pressure Lamp Using Coaxial Line Networks JF - IEEE Transactions on Microwave Theory and Techniques N2 - This paper describes the development of a capacitively coupled high-pressure lamp with input power between 20 and 43 W at 2.45 GHz, using a coaxial line network. Compared with other electrodeless lamp systems, no cavity has to be used and a reduction in the input power is achieved. Therefore, this lamp is an alternative to the halogen incandescent lamp for domestic lighting. To serve the demands of domestic lighting, the filling of the lamp is optimized over all other resulting requirements, such as high efficacy at low induced powers and fast startups. A workflow to develop RF-driven plasma applications is presented, which makes use of the hot S-parameter technique. Descriptions of the fitting process inside a circuit and FEM simulator are given. Results of the combined ignition and operation network from simulations and measurements are compared. An initial prototype is built and measurements of the lamp's lighting properties are presented along with an investigation of the efficacy optimizations using large signal amplitude modulation. With this lamp, an efficacy of 135 lmW -1 is achieved. Y1 - 2016 U6 - http://dx.doi.org/10.1109/TMTT.2016.2600326 SN - 0018-9480 VL - 64 IS - 10 SP - 3363 EP - 3368 PB - IEEE CY - New York, NY ER - TY - JOUR A1 - Pilas, Johanna A1 - Yazici, Yasemen A1 - Selmer, Thorsten A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Optimization of an amperometric biosensor array for simultaneous measurement of ethanol, formate, d- and l-lactate JF - Electrochimica Acta N2 - The immobilization of NAD+-dependent dehydrogenases, in combination with a diaphorase, enables the facile development of multiparametric sensing devices. In this work, an amperometric biosensor array for simultaneous determination of ethanol, formate, d- and l-lactate is presented. Enzyme immobilization on platinum thin-film electrodes was realized by chemical cross-linking with glutaraldehyde. The optimization of the sensor performance was investigated with regard to enzyme loading, glutaraldehyde concentration, pH, cofactor concentration and temperature. Under optimal working conditions (potassium phosphate buffer with pH 7.5, 2.5 mmol L-1 NAD+, 2.0 mmol L-1 ferricyanide, 25 °C and 0.4% glutaraldehyde) the linear working range and sensitivity of the four sensor elements was improved. Simultaneous and cross-talk free measurements of four different metabolic parameters were performed successfully. The reliable analytical performance of the biosensor array was demonstrated by application in a clarified sample of inoculum sludge. Thereby, a promising approach for on-site monitoring of fermentation processes is provided. KW - Simultaneous determination KW - Enzymatic biosensor KW - Diaphorase KW - Dehydrogenase Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.electacta.2017.07.119 SN - 0013-4686 VL - 251 SP - 256 EP - 262 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Röhlen, Desiree A1 - Pilas, Johanna A1 - Schöning, Michael Josef A1 - Selmer, Thorsten T1 - Development of an amperometric biosensor platform for the combined determination of l-Malic, Fumaric, and l-Aspartic acid JF - Applied Biochemistry and Biotechnology N2 - Three amperometric biosensors have been developed for the detection of L-malic acid, fumaric acid, and L -aspartic acid, all based on the combination of a malate-specific dehydrogenase (MDH, EC 1.1.1.37) and diaphorase (DIA, EC 1.8.1.4). The stepwise expansion of the malate platform with the enzymes fumarate hydratase (FH, EC 4.2.1.2) and aspartate ammonia-lyase (ASPA, EC 4.3.1.1) resulted in multi-enzyme reaction cascades and, thus, augmentation of the substrate spectrum of the sensors. Electrochemical measurements were carried out in presence of the cofactor β-nicotinamide adenine dinucleotide (NAD+) and the redox mediator hexacyanoferrate (III) (HCFIII). The amperometric detection is mediated by oxidation of hexacyanoferrate (II) (HCFII) at an applied potential of + 0.3 V vs. Ag/AgCl. For each biosensor, optimum working conditions were defined by adjustment of cofactor concentrations, buffer pH, and immobilization procedure. Under these improved conditions, amperometric responses were linear up to 3.0 mM for L-malate and fumarate, respectively, with a corresponding sensitivity of 0.7 μA mM−1 (L-malate biosensor) and 0.4 μA mM−1 (fumarate biosensor). The L-aspartate detection system displayed a linear range of 1.0–10.0 mM with a sensitivity of 0.09 μA mM−1. The sensor characteristics suggest that the developed platform provides a promising method for the detection and differentiation of the three substrates. Y1 - 2017 U6 - http://dx.doi.org/10.1007/s12010-017-2578-1 SN - 1559-0291 VL - 183 SP - 566 EP - 581 PB - Springer CY - Berlin ER - TY - JOUR A1 - Honarvarfard, Elham A1 - Gamella, Maria A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Katz, Evgeny T1 - An enzyme-based reversible Controlled NOT (CNOT) logic gate operating on a semiconductor transducer JF - Applied Materials Today N2 - An enzyme-based biocatalytic system mimicking operation of a logically reversible Controlled NOT (CNOT) gate has been interfaced with semiconductor electronic transducers. Electrolyte–insulator–semiconductor (EIS) structures have been used to transduce chemical changes produced by the enzyme system to an electronically readable capacitive output signal using field-effect features of the EIS device. Two enzymes, urease and esterase, were immobilized on the insulating interface of EIS structure producing local pH changes performing XOR logic operation controlled by various combinations of the input signals represented by urea and ethyl butyrate. Another EIS transducer was functionalized with esterase only, thus performing Identity (ID) logic operation for the ethyl butyrate input. Both semiconductor devices assembled in parallel operated as a logically reversible CNOT gate. The present system, despite its simplicity, demonstrated for the first time logically reversible function of the enzyme system transduced electronically with the semiconductor devices. The biomolecular realization of a CNOT gate interfaced with semiconductors is promising for integration into complex biomolecular networks and future biosensor/biomedical applications. KW - Electrolyte–insulator–semiconductor KW - Capacitive field-effect KW - CNOT KW - XOR KW - Enzyme logic gate Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.apmt.2017.08.003 SN - 2352-9407 VL - 9 SP - 266 EP - 270 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Lambers, Andreas A1 - Bragard, Michael T1 - Kinetische Skulptur - Treffen sich ein E-Techniker und ein Künstler ... JF - Elektor : learn, design, share N2 - Die Verbindung der Welten dressierter Elektronen und grenzenloser Kreativität bietet ein großes Potential; zum Beispiel bei modernen Skulpturen, deren Form sich durch Motoren verändern kann. An der FH Aachen wurde ein solches Projekt verwirklicht: Eine Matrix aus Holzkugeln kann Piktogramme anzeigen, aber auch mathematische Funktionen visualisieren. In diesem Artikel beschreiben wir die clevere Ansteuerung der Motoren. Y1 - 2017 SN - 0932-5468 VL - 48 IS - 9 SP - 78 EP - 83 PB - Elektor-Verlag CY - Aachen ER - TY - JOUR A1 - Tran, Linda A1 - Mottaghy, K. A1 - Arlt-Körfer, Sabine A1 - Waluga, Christian A1 - Behbahani, Mehdi T1 - An experimental study of shear-dependent human platelet adhesion and underlying protein-binding mechanisms in a cylindrical Couette system JF - Biomedizinische Technik Y1 - 2017 U6 - http://dx.doi.org/10.1515/bmt-2015-0034 SN - 0013-5585 VL - 62 IS - 4 SP - 383 EP - 392 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Scholl, Fabio A1 - Morais, Paulo A1 - Gabriel, Rayla A1 - Schöning, Michael Josef A1 - Siqueira, Jose Roberto, Jr. A1 - Caseli, Luciano T1 - Carbon nanotubes arranged as smart interfaces in lipid Langmuir-Blodgett films enhancing the enzymatic properties of penicillinase for biosensing applications JF - Applied Materials & Interfaces N2 - In this paper, carbon nanotubes (CNTs) were incorporated in penicillinase-phospholipid Langmuir and Langmuir–Blodgett (LB) films to enhance the enzyme catalytic properties. Adsorption of the penicillinase and CNTs at dimyristoylphosphatidic acid (DMPA) monolayers at the air–water interface was investigated by surface pressure–area isotherms, vibrational spectroscopy, and Brewster angle microscopy. The floating monolayers were transferred to solid supports through the LB technique, forming mixed DMPA-CNTs-PEN films, which were investigated by quartz crystal microbalance, vibrational spectroscopy, and atomic force microscopy. Enzyme activity was studied with UV–vis spectroscopy and the feasibility of the supramolecular device nanostructured as ultrathin films were essayed in a capacitive electrolyte–insulator–semiconductor (EIS) sensor device. The presence of CNTs in the enzyme–lipid LB film not only tuned the catalytic activity of penicillinase but also helped conserve its enzyme activity after weeks, showing increased values of activity. Viability as penicillin sensor was demonstrated with capacitance/voltage and constant capacitance measurements, exhibiting regular and distinctive output signals over all concentrations used in this work. These results may be related not only to the nanostructured system provided by the film, but also to the synergism between the compounds on the active layer, leading to a surface morphology that allowed a fast analyte diffusion because of an adequate molecular accommodation, which also preserved the penicillinase activity. This work therefore demonstrates the feasibility of employing LB films composed of lipids, CNTs, and enzymes as EIS devices for biosensing applications. Y1 - 2017 U6 - http://dx.doi.org/10.1021/acsami.7b08095 SN - 1944-8252 VL - 9 IS - 36 SP - 31054 EP - 31066 PB - ACS CY - Washington ER - TY - JOUR A1 - Werner, Frederik A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Lateral resolution enhancement of pulse-driven light-addressable potentiometric sensor JF - Sensor and Actuators B: Chemical N2 - To study chemical and biological processes, spatially resolved determination of the concentrations of one or more analyte species is of distinct interest. With a light-addressable potentiometric sensor (LAPS), chemical images can be created, which visualize the concentration distribution above the sensor plate. One important challenge is to achieve a good lateral resolution in order to detect events that take place in a small and limited region. LAPS utilizes a focused light spot to address the measurement region. By moving this light spot along the semiconductor sensor plate, the concentration distribution can be observed. In this study, we show that utilizing a pulse as light excitation instead of a traditionally used continuously modulated light excitation, the lateral resolution can be improved by a factor of 6 or more. KW - Chemical images KW - LAPS KW - Light-addressable potentiometric sensor Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.snb.2017.02.057 SN - 0925-4005 VL - 248 SP - 961 EP - 965 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Hayashi, Kosuke A1 - Sakamoto, Azuma A1 - Werner, Frederik A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - A high-Q resonance-mode measurement of EIS capacitive sensor by elimination of series resistance JF - Sensor and Actuators B: Chemical N2 - An EIS capacitive sensor is a semiconductor-based potentiometric sensor, which is sensitive to the ion concentration or pH value of the solution in contact with the sensing surface. To detect a small change in the ion concentration or pH, a small capacitance change must be detected. Recently, a resonance-mode measurement was proposed, in which an inductor was connected to the EIS capacitive sensor and the resonant frequency was correlated with the pH value. In this study, the Q factor of the resonant circuit was enhanced by canceling the internal resistance of the reference electrode and the internal resistance of the inductor coil with the help of a bypass capacitor and a negative impedance converter, respectively. 1% variation of the signal in the developed system corresponded to a pH change of 3.93 mpH, which was about 1/12 of the conventional method, suggesting a better performance in detection of a small pH change. KW - Negative impedance convertor KW - Resonance-mode measurement KW - Chemical sensor KW - EIS capacitive sensor Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.snb.2017.03.002 SN - 0925-4005 VL - 248 SP - 1006 EP - 1010 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Arreola, Julio A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Effect of O2 plasma on properties of electrolyte-insulator-semiconductor structures JF - physica status solidi a : applications and materials sciences N2 - Prior to immobilization of biomolecules or cells onto biosensor surfaces, the surface must be physically or chemically activated for further functionalization. Organosilanes are a versatile option as they facilitate the immobilization through their terminal groups and also display self-assembly. Incorporating hydroxyl groups is one of the important methods for primary immobilization. This can be done, for example, with oxygen plasma treatment. However, this treatment can affect the performance of the biosensors and this effect is not quite well understood for surface functionalization. In this work, the effect of O2 plasma treatment on EIS sensors was investigated by means of electrochemical characterizations: capacitance–voltage (C–V) and constant capacitance (ConCap) measurements. After O2 plasma treatment, the potential of the EIS sensor dramatically shifts to a more negative value. This was successfully reset by using an annealing process. KW - surface functionalization KW - O2 plasma KW - hydroxylation KW - electrolyte-insulator semiconductor sensor (EIS) KW - annealing Y1 - 2017 U6 - http://dx.doi.org/10.1002/pssa.201700025 SN - 1862-6319 VL - 214 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Molinnus, Denise A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Katz, Evgeny A1 - Schöning, Michael Josef T1 - Coupling of Biomolecular Logic Gates with Electronic Transducers: From Single Enzyme Logic Gates to Sense/Act/Treat Chips JF - Electroanalysis N2 - The integration of biomolecular logic principles with electronic transducers allows designing novel digital biosensors with direct electrical output, logically triggered drug-release, and closed-loop sense/act/treat systems. This opens new opportunities for advanced personalized medicine in the context of theranostics. In the present work, we will discuss selected examples of recent developments in the field of interfacing enzyme logic gates with electrodes and semiconductor field-effect devices. Special attention is given to an enzyme OR/Reset logic gate based on a capacitive field-effect electrolyte-insulator-semiconductor sensor modified with a multi-enzyme membrane. Further examples are a digital adrenaline biosensor based on an AND logic gate with binary YES/NO output and an integrated closed-loop sense/act/treat system comprising an amperometric glucose sensor, a hydrogel actuator, and an insulin (drug) sensor. Y1 - 2017 U6 - http://dx.doi.org/10.1002/elan.201700208 SN - 1521-4109 VL - 29 IS - 8 SP - 1840 EP - 1849 PB - Wiley CY - Weinheim ER -