@article{AchtsnichtPourshahidiOffenhaeusseretal.2019, author = {Achtsnicht, Stefan and Pourshahidi, Ali Mohammad and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim}, title = {Multiplex detection of different magnetic beads using frequency scanning in magnetic frequency mixing technique}, series = {Sensors}, volume = {19}, journal = {Sensors}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s19112599}, pages = {13 Seiten}, year = {2019}, abstract = {In modern bioanalytical methods, it is often desired to detect several targets in one sample within one measurement. Immunological methods including those that use superparamagnetic beads are an important group of techniques for these applications. The goal of this work is to investigate the feasibility of simultaneously detecting different superparamagnetic beads acting as markers using the magnetic frequency mixing technique. The frequency of the magnetic excitation field is scanned while the lower driving frequency is kept constant. Due to the particles' nonlinear magnetization, mixing frequencies are generated. To record their amplitude and phase information, a direct digitization of the pickup-coil's signal with subsequent Fast Fourier Transformation is performed. By synchronizing both magnetic beads using frequency scanning in magnetic frequency mixing technique magnetic fields, a stable phase information is gained. In this research, it is shown that the amplitude of the dominant mixing component is proportional to the amount of superparamagnetic beads inside a sample. Additionally, it is shown that the phase does not show this behaviour. Excitation frequency scans of different bead types were performed, showing different phases, without correlation to their diverse amplitudes. Two commercially available beads were selected and a determination of their amount in a mixture is performed as a demonstration for multiplex measurements.}, language = {en} } @article{AchtsnichtSchoenenbornOffenhaeusseretal.2019, author = {Achtsnicht, Stefan and Sch{\"o}nenborn, Kristina and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim}, title = {Measurement of the magnetophoretic velocity of different superparamagnetic beads}, series = {Journal of Magnetism and Magnetic Materials}, volume = {477}, journal = {Journal of Magnetism and Magnetic Materials}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0304-8853}, doi = {10.1016/j.jmmm.2018.10.066}, pages = {244 -- 248}, year = {2019}, abstract = {The movement of magnetic beads due to a magnetic field gradient is of great interest in different application fields. In this report we present a technique based on a magnetic tweezers setup to measure the velocity factor of magnetically actuated individual superparamagnetic beads in a fluidic environment. Several beads can be tracked simultaneously in order to gain and improve statistics. Furthermore we show our results for different beads with hydrodynamic diameters between 200 and 1000 nm from diverse manufacturers. These measurement data can, for example, be used to determine design parameters for a magnetic separation system, like maximum flow rate and minimum separation time, or to select suitable beads for fixed experimental requirements.}, language = {en} } @article{AchtsnichtToedterNiehuesetal.2019, author = {Achtsnicht, Stefan and T{\"o}dter, Julia and Niehues, Julia and Tel{\"o}ken, Matthias and Offenh{\"a}usser, Andreas and Krause, Hans-Joachim and Schr{\"o}per, Florian}, title = {3D printed modular immunofiltration columns for frequency mixing-based multiplex magnetic immunodetection}, series = {Sensors}, volume = {19}, journal = {Sensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {10.3390/s19010148}, pages = {15 Seiten}, year = {2019}, abstract = {For performing point-of-care molecular diagnostics, magnetic immunoassays constitute a promising alternative to established enzyme-linked immunosorbent assays (ELISA) because they are fast, robust and sensitive. Simultaneous detection of multiple biomolecular targets from one body fluid sample is desired. The aim of this work is to show that multiplex magnetic immunodetection based on magnetic frequency mixing by means of modular immunofiltration columns prepared for different targets is feasible. By calculations of the magnetic response signal, the required spacing between the modules was determined. Immunofiltration columns were manufactured by 3D printing and antibody immobilization was performed in a batch approach. It was shown experimentally that two different target molecules in a sample solution could be individually detected in a single assaying step with magnetic measurements of the corresponding immobilization filters. The arrangement order of the filters and of a negative control did not influence the results. Thus, a simple and reliable approach to multi-target magnetic immunodetection was demonstrated.}, language = {en} } @article{Ackermann1996, author = {Ackermann, Hans-Josef}, title = {Single chip hardware support for rasterization and texture mapping}, series = {Computers \& graphics : CAG ; an international journal of applications in computer graphics. 20 (1996), H. 4}, journal = {Computers \& graphics : CAG ; an international journal of applications in computer graphics. 20 (1996), H. 4}, isbn = {0097-8493}, pages = {503 -- 514}, year = {1996}, language = {en} } @book{Ackermann1996, author = {Ackermann, Hans-Josef}, title = {Hardware-Unterst{\"u}tzung f{\"u}r effiziente Dreiecksrasterisierung und texture mapping}, publisher = {Shaker}, address = {Aachen}, isbn = {3826512081}, pages = {III, 162 S : Ill., graph. Darst.}, year = {1996}, language = {de} } @article{Ackermann1997, author = {Ackermann, Hans-Josef}, title = {Morphing- und Level-of-Detail-Techniken zur Reduzierung des Darstellungsaufwands bei Echtzeit-Sichtsimulationen}, series = {Digital controls for high resolution display : JESSI Europrojekt No. 3203000, AE-36 ; Abschlußbericht ; Laufzeit u. Berichtszeitraum: 01.01.1995 bis 31.12.1996.}, journal = {Digital controls for high resolution display : JESSI Europrojekt No. 3203000, AE-36 ; Abschlußbericht ; Laufzeit u. Berichtszeitraum: 01.01.1995 bis 31.12.1996.}, address = {Erlangen}, year = {1997}, language = {en} } @article{AckermannJaegerOsterfeldetal.1993, author = {Ackermann, Hans-Josef and J{\"a}ger, Michael and Osterfeld, Utz and Hornung, Christoph}, title = {Building a Multimedia ISDN PC / J{\"a}ger, Michael ; Osterfeld, Utz ; Ackermann, Hans-Josef ; Hornung, Christoph}, series = {Institute of Electrical and Electronics Engineers: IEEE computer graphics and applications. 13 (1993), H. 5}, journal = {Institute of Electrical and Electronics Engineers: IEEE computer graphics and applications. 13 (1993), H. 5}, isbn = {0272-1716}, pages = {24 -- 33}, year = {1993}, language = {en} } @book{AckermannMehlPeischl1990, author = {Ackermann, Hans-Josef and Mehl, Max and Peischl, Markus}, title = {Modulares Graphik-Subsystem f{\"u}r die Echtzeitdarstellung von 3D-Anwendungen : Abschlußbericht ; Contract NT 2815-A-8 / Hans-Josef Ackermann; Max Mehl; Markus Peischl. Fachbereich Informatik, Technische Hochschule Darmstadt; Bundesministerium f{\"u}r Forschung und Technologie, Bonn}, publisher = {Techn. Hochschule}, address = {Darmstadt}, pages = {ca. 100 S.}, year = {1990}, language = {de} } @masterthesis{Ackermann2024, type = {Bachelor Thesis}, author = {Ackermann, Vincent}, title = {Filos : Design eines Front-Ends f{\"u}r das robotergef{\"u}hrte Laser-Osteotom-System STELLA.}, publisher = {FH Aachen}, address = {Aachen}, pages = {70 Seiten}, year = {2024}, abstract = {In der Abschlussarbeit „FILOS" wurde in Zusammenarbeit mit dem Fraunhofer-Institut f{\"u}r Lasertechnik (ILT) ein Front-End f{\"u}r das laserbasierte Osteotom STELLA entwickelt. STELLA soll Kraniotomie (das Er{\"o}ffnen des Sch{\"a}dels) im wachen Zustand erm{\"o}glichen und erfordert eine benutzerfreundliche Bedienungsplattform sowie ein funktionales und {\"a}sthetisches Design. Das Ziel von „FILOS" war es, ein Geh{\"a}use zu entwerfen, das den medizinischen Anforderungen entspricht, und ein Bedienkonzept zu entwickeln, dass die Akzeptanz bei Patient:innen und Anwender:innen f{\"o}rdert. Durch Expert:innen-Interviews mit Neurochirurg:innen und enge Zusammenarbeit mit dem ILT wurde ein durchdachtes Design entwickelt. Dieses soll den Anforderungen der Anwender:innen gerecht werden, das zuk{\"u}nftige Operationssystem repr{\"a}sentieren und somit einen Mehrwert in der Medizin schaffen.}, language = {de} } @inproceedings{AdamsLosekammCzupalla2020, author = {Adams, Moritz and Losekamm, Martin J. and Czupalla, Markus}, title = {Development of the Thermal Control System for the RadMap Telescope Experiment on the International Space Station}, series = {International Conference on Environmental Systems}, booktitle = {International Conference on Environmental Systems}, pages = {1 -- 10}, year = {2020}, language = {en} }