TY  - JOUR
A1  - Welden, Rene
A1  - Jablonski, Melanie
A1  - Wege, Christina
A1  - Keusgen, Michael
A1  - Wagner, Patrick Hermann
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase
JF  - Biosensors
N2  - The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte’s pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.
KW  - microfluidics
KW  - enzyme kinetics
KW  - actuator-sensor system
KW  - light-addressable electrode
KW  - light-addressable potentiometric sensor
Y1  - 2021
U6  - https://doi.org/10.3390/bios11060171
SN  - 2079-6374
N1  - This article belongs to the Special Issue "Selected Papers from the 1st International Electronic Conference on Biosensors (IECB 2020)"
VL  - 11
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Ferrein, Alexander
A1  - Calmes, Laurent
A1  - Lakemeyer, Gerhard
A1  - Wagner, Hermann
T1  - Von Schleiereulen und fussballspielenden Robotern / Calmes, Laurent ; Ferrein, Alexander ; Lakemeyer, Gerhard ; Wagner, Hermann
JF  - RWTH Themen (2006)
Y1  - 2006
SN  - 0179-079X
SP  - 30
EP  - 33
ER  - 
TY  - CHAP
A1  - Goeckel, Tom
A1  - Schiffer, Stefan
A1  - Wagner, Hermann
A1  - Lakemeyer, Gerhard
T1  - The Video Conference Tool Robot ViCToR
T2  - Intelligent Robotics and Applications : 8th International Conference, ICIRA 2015, Portsmouth, UK, August 24-27, 2015, Proceedings, Part II
N2  - We present a robotic tool that autonomously follows a conversation to enable remote presence in video conferencing. When humans participate in a meeting with the help of video conferencing tools, it is crucial that they are able to follow the conversation both with acoustic and visual input. To this end, we design and implement a video conferencing tool robot that uses binaural sound source localization as its main source to autonomously orient towards the currently talking speaker. To increase robustness of the acoustic cue against noise we supplement the sound localization with a source detection stage. Also, we include a simple onset detector to retain fast response times. Since we only use two microphones, we are confronted with ambiguities on whether a source is in front or behind the device. We resolve these ambiguities with the help of face detection and additional moves. We tailor the system to our target scenarios in experiments with a four minute scripted conversation. In these experiments we evaluate the influence of different system settings on the responsiveness and accuracy of the device.
Y1  - 2015
SN  - 978-3-319-22876-1
U6  - https://doi.org/10.1007/978-3-319-22876-1_6
N1  - Lecture Notes in Computer Science ; 9245
SP  - 61
EP  - 73
PB  - Springer
ER  -