@inproceedings{BirkenmaierKrenkel, author = {Birkenmaier, Clemens and Krenkel, Lars}, title = {Convolutional Neural Networks for Approximation of Blood Flow in Artificial Lungs}, series = {New Results in Numerical and Experimental Fluid Mechanics XIII: Contributions to the 22nd STAB/DGLR Symposium}, booktitle = {New Results in Numerical and Experimental Fluid Mechanics XIII: Contributions to the 22nd STAB/DGLR Symposium}, number = {1. Auflage}, editor = {Dillmann, Andreas and Heller, Gerd and Kr{\"a}mer, Ewald and Wagner, Claus}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-030-79560-3}, doi = {10.1007/978-3-030-79561-0_43}, pages = {451 -- 460}, abstract = {Blood flow in channels of varying diameters <500μm exhibits strong non-linear effects. Multiphase finite volume approaches are feasible, but still computationally costly. Here, the feasibility of applying convolutional neural networks for blood flow prediction in artificial lungs is investigated. Training targets are precomputed using an Eulerian two-phase approach. To match with experimental data, the interphase drag and lift, as well as intraphase shear-thinning are adapted. A recursively branching regression network and convolution/deconvolution networks with plain skip connections and densely connected skips are investigated. A priori knowledge is incorporated in the loss functional to prevent the network from learning non-physical solutions. Inference from neural networks is approximately six orders of magnitude faster than the classical finite volume approach. Even if resulting in comparably coarse flow fields, the neural network predictions can be used as close to convergence initial solutions greatly accelerating classical flow computations.}, language = {en} } @inproceedings{TauwaldQuadrioRuettenetal., author = {Tauwald, Sandra Melina and Quadrio, Maurizio and R{\"u}tten, Markus and Stemmer, Christian and Krenkel, Lars}, title = {High Spatial Resolution Tomo-PIV of the Trachea Focussing on the Physiological Breathing Cycle}, series = {New Results in Numerical and Experimental Fluid Mechanics XIV - Contributions to the 23nd STAB/DGLR Symposium}, booktitle = {New Results in Numerical and Experimental Fluid Mechanics XIV - Contributions to the 23nd STAB/DGLR Symposium}, publisher = {Springer}, abstract = {Investigations of complex patient-specific flow in the nasopharynx requires high resolution numerical calculations validated by reliable experiments. When building the validation base and the benchmark of computational fluid dynamics, an experimental setup of the nasal airways was developed. The applied optical measurement technique of tomo-PIV supplies information on the governing flow field in three dimensions. This paper presents tomo-PIV measurements of the highly complex patient-specific geometry of the human trachea. A computertomographic scan of a person's head builds the basis of the experimental silicone model of the nasal airways. An optimised approach for precise refractive index matching avoids optical distortions even in highly complex non-free-of-sight 3D geometries. A linear-motor-driven pump generates breathing scenarios, based on measured breathing cycles. Adjusting of the CCD cameras' double-frame-rate PIV-Δt enables the detailed analysis of flow structures during different cycle phases. Merging regions of interest enables high spatial resolution acquisition of the flow field.}, language = {en} } @misc{Krenkel, author = {Krenkel, Lars}, title = {Relevanz von Aerosolen im klinischen Kontext}, series = {Innovationstag Hygiene 2021, Continental Arena, Regensburg, Deutschland}, journal = {Innovationstag Hygiene 2021, Continental Arena, Regensburg, Deutschland}, language = {de} } @incollection{Raptis, author = {Raptis, Georgios}, title = {Gew{\"a}hrleistung der IT-Sicherheit bei vernetzten Implantaten}, series = {Biomedizinische Technik: Vernetzte und intelligente Implantate}, booktitle = {Biomedizinische Technik: Vernetzte und intelligente Implantate}, editor = {Marschner, Uwe and Clasbrummel, Bernhard and Dehm, Johannes}, publisher = {Walter de Gruyter}, isbn = {978-3-11-034927-6}, pages = {182 -- 192}, subject = {Implantat}, language = {de} } @article{EigenbergerFelthausSchratzenstalleretal., author = {Eigenberger, Andreas and Felthaus, Oliver and Schratzenstaller, Thomas and Haerteis, Silke and Utpatel, Kirsten and Prantl, Lukas}, title = {The Effects of Shear Force-Based Processing of Lipoaspirates on White Adipose Tissue and the Differentiation Potential of Adipose Derived Stem Cells}, series = {cells}, volume = {11}, journal = {cells}, number = {16}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/cells11162543}, pages = {13}, abstract = {Autologous lipotransfer is a promising method for tissue regeneration, because white adipose tissue contains a heterogeneous cell population, including mesenchymal stem cells, endothelial cells, immune cells, and adipocytes. In order to improve the outcome, adipose tissue can be processed before application. In this study, we investigated changes caused by mechanical processing. Lipoaspirates were processed using sedimentation, first-time centrifugation, shear-force homogenization, and second-time centrifugation. The average adipocyte size, stromal vascular cell count, and adipocyte depot size were examined histologically at every processing step. In addition, the adipose derived stem cells (ADSCs) were isolated and differentiated osteogenically and adipogenically. While homogenization causes a disruption of adipocyte depots, the shape of the remaining adipocytes is not changed. On average, these adipocytes are smaller than the depot adipocytes, they are surrounded by the ECM, and therefore mechanically more stable. The volume loss of adipocyte depots leads to a significant enrichment of stromal vascular cells such as ADSCs. However, the mechanical processing does not change the potential of the ADSCs to differentiate adipogenically or steogenically. It thus appears that mechanically processed lipoaspirates are promising for the reparation of even mechanically stressed tissue as that found in nasolabial folds. The changes resulting from the processing correspond more to a filtration of mechanically less stable components than to a manipulation of the tissue.}, language = {en} } @article{Pfingsten, author = {Pfingsten, Andrea}, title = {Genauigkeit des Lachman Tests zur Feststellung einer Ruptur des vorderen Kreuzbandes}, series = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, volume = {61}, journal = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, number = {2}, publisher = {Pflaum}, address = {M{\"u}nchen}, issn = {1614-0397}, pages = {108 -- 123}, abstract = {Die Ruptur des vorderen Kreuzbandes (ACL, anterior cruciate ligament) ist die h{\"a}ufigste Bandverletzung des Kniegelenks und kann zu schwerwiegenden Folgen f{\"u}hren. Um diese im Rahmen einer Behandlung oder eines Forschungsprojektes manuell zu diagnostizieren, werden geeignete Assessments ben{\"o}tigt. Der vorliegende systematische Review stellt die vorhandene Evidenz des Lachman-Tests als diagnostisches Verfahren zur Feststellung einer ACL-Ruptur dar.}, language = {de} } @article{PfingstenTrickesMaxetal., author = {Pfingsten, Andrea and Trickes, Claudia and Max, Susanne and Borgetto, Bernhard}, title = {Die Forschungspyramide. Ein Modell zur Bewertung der Evidenz durch Zusammenf{\"u}hrung verschiedener Forschungsans{\"a}tze in einem systematischen Review}, series = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, volume = {63}, journal = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, number = {10}, publisher = {Pflaum}, address = {M{\"u}nchen}, issn = {1614-0397}, pages = {16 -- 18}, language = {de} } @article{Pfingsten, author = {Pfingsten, Andrea}, title = {Untersuchung des vorderen Kreuzbandes. Indikation, Ausf{\"u}hrung und Interpretation des Lachman-Tests im Rahmen der Befunderhebung des Kniegelenks}, series = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, volume = {61}, journal = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, number = {2}, publisher = {Pflaum}, address = {M{\"u}nchen}, issn = {1614-0397}, pages = {38 -- 40}, language = {de} } @incollection{PfingstenBorgetto, author = {Pfingsten, Andrea and Borgetto, Bernhard}, title = {Akademisierung der therapeutischen Gesundheitsberufe}, series = {Perspektive Gesundheit 2030. Gesellschaft, Politik, Transformation}, booktitle = {Perspektive Gesundheit 2030. Gesellschaft, Politik, Transformation}, editor = {Baas, Jens}, publisher = {Medizinisch Wissenschaftliche Verlagsgesellschaft}, address = {Berlin}, isbn = {9783954666331}, pages = {173 -- 183}, subject = {Heilberuf}, language = {de} } @article{Pfingsten, author = {Pfingsten, Andrea}, title = {Bewertung der Gesamtevidenz in Reviews. Kombination beobachtender und experimenteller Studien}, series = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, volume = {63}, journal = {pt - Zeitschrift f{\"u}r Physiotherapeuten}, number = {12}, publisher = {Pflaum}, address = {M{\"u}nchen}, issn = {1614-0397}, pages = {18 -- 20}, language = {de} }