TY - GEN A1 - Singh, Max Diamond T1 - Zusätzliche Anforderungen an Produktdaten und technische Dokumentation durch die MDR T2 - Medizintechnik Kongress 2018: Effizienz in der Medizinprodukteentwicklung vor dem Hintergrund von MDR und IVDR ; Frankfurt am Main, 08.11.2018, [Veranstalter: Velten Consulting & ILC Consulting] Y1 - 2018 ER - TY - GEN A1 - Singh, Max Diamond T1 - EU-MDR from a Notified Body Perspective - aktuelle Situation hinsichtlich der Anforderungen zum Lieferantenmanagement BT - Tuttlingen, Technology Mountains / Medical Mountains, 2019 Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - EU Medical Device Regulation: Top Challenges of Orthopedic Manufacturers T2 - OMTEC 2019 : 15th Annual Orthopedic Manufacturing & Technology Exposition and Conference, Chicago, 11.6.2019 Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Conformity Assessment Procedure MDR BT - [Vortrag gehalten am 24.02.2020] T2 - MDR Training: Person Responsible for Regulatory Compliance Course, 24.-25.02.2020, Tel Aviv, Obelis Academy Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Managing Innovation from the Notified Body Perspective - Understanding the 3 C’s of EU Regulations to Ensure Product Compliance: Changes, Challenges and Contributions T2 - 3rd annual european medical device and diagnostic product development and management meeting, 12-13 February 2019, Brussels Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Notified body feedback: PSUR Forms. Post Market Surveillance & Vigilance BT - [Vortrag gehalten am 24.06.2020] T2 - MedTech Summit 2020: EU MDR & IVDR: the end is in sight, Dublin/virtual, 20.-26.06.2020 Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - MDR - Die neuen rechtlichen Bedingungen für Händler und Hersteller: aus der Sicht einer benannten Stelle T2 - MEGRA Jahrestagung. - Wien, 18.05.2020 [Veranstalter: Mitteleuropäische Gesellschaft für Regulatory Affairs] Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Innovation challenges for orthopedic device manufacturers under the new EU MDR BT - a notified body perspective T2 - ORS (Orthopaedic Research Society) Annual Meeting. - Phoenix, Arizona, 08. - 11.02.2020 Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - KARL STORZ Navigation Panel Unit - Navigation for ENT surgery T2 - FESS 2010 : International Workshop on FESS ; Lectures & Live Surgery. - Royal Pearl Hospital, Tiruchirappalli (Indien), 10.-11.04.2010 Y1 - 2010 ER - TY - GEN A1 - Singh, Max Diamond T1 - Medical Device Regulation BT - Kurzer Überblick zur Zulassung von Medizinprodukten T2 - Forum MedTech Pharma: Start-ups in der Medizintechnik: Besonderheiten und Fallbeispiele, München, 17.7.2019 Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Market Access for Devices under MDD and MDR: Obligations for Manufacturers T2 - OSMA - Orthopedic Surgical Manufacturers Association, Winter Educational Program - virtual Y1 - 2021 ER - TY - GEN A1 - Singh, Max Diamond T1 - Innovationsmanagement BT - Sitzung des Ulmer Arbeitskreises Innovationsmanagement, Ulm, 03.11.2011 Y1 - 2011 ER - TY - GEN A1 - Singh, Max Diamond T1 - General Overview of the Medical Device Regulation T2 - MDR-Roadshow - TÜV SÜD MHS, India Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Stakeholder view on Post Market Surveillance under the EU MDR: Timelines, Compliance and Requirements ; Post Market Surveillance & Vigilance BT - [Vortrag gehalten am: 23.6.2020] T2 - MedTech summit 2020: EU MDR & IVDR: the end ist in sight, 22.-26.06.2020, Dublin/virtual Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Quality in Medical Device Innovation for Start-ups, SME, and large enterprises through the new Medical Device Regulation T2 - 3rd European QA Conference, Dublin, 06. - 08.11.2019 Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Technical Documentation MDR / IVDR, including the Declaration of Conformity BT - [Vortrag gehalten am 24.02.2020] T2 - MDR Training: Person Responsible for Regulatory Compliance, 24.-25.02.2020, Tel Aviv, Obelis Academy Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Notified Body Viewpoint : Preparing for MDR/IVDR T2 - MDR/IVDR - Status Report from Stakeholders. Where are we now in November 2018? - Bern, 22.11.2018 - [Veranstalter: RAPS : Regulatory Affairs Professionals Society] Y1 - 2018 ER - TY - GEN A1 - Singh, Max Diamond T1 - Reclassification of Orthopedic Devices per the Medical Device Regulation T2 - OSMA Winter Educational Program, St. Petersburg/USA, 2019. - [Veranstalter: Orthopedic Surgical Manufacturers Association (OSMA)] Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Strategies to Navigate to the EU MDR and Clinical Requirements T2 - Regulatory Affairs Professionals Society (RAPS): Session 1 - Tampa, Florida 2019 Y1 - 2019 ER - TY - GEN A1 - Singh, Max Diamond T1 - Herausforderungen der Medizinprodukteindustrie bei der Internationalisierung T2 - Studienwoche an der HNU (Hochschule Neu-Ulm) 2020 Y1 - 2020 ER - TY - GEN A1 - Singh, Max Diamond T1 - Technical Aspects for Navigated Sinus Surgery T2 - 4th Workshop on Endoscopic Surgery of the Maxillary Sinus and Navigation, Tübingen University Hospital, 2009 Y1 - 2009 ER - TY - GEN A1 - Singh, Max Diamond T1 - Overview of the Medical Device Regulation (MDR) BT - MDR-Roadshow TÜV SÜD MHS, San Diego & Minneapolis, 2018 Y1 - 2018 ER - TY - JOUR A1 - Singh, Max Diamond T1 - Orthopedic Medical Devices Under The Scope of The EU MDR JF - MedTech Outlook Y1 - 2019 UR - https://embedded-solutions.medicaltechoutlook.com/cxoinsight/orthopedic-medical-devices-under-the-scope-of-the-eu-mdr-nwid-921.html ER - TY - GEN A1 - Singh, Max Diamond T1 - Joint NB-Position Paper on Spinal Classification per the MDR Y1 - 2019 UR - https://www.team-nb.org/wp-content/uploads/2019/01/Joint-NB-Spinal-Classification-Decision-Tree_final.pdf ER - TY - THES A1 - Singh, Max Diamond T1 - Aspects of the Dynamics of Spine Surgery Technologies: Assessing the Reality of Innovation and Entrepreneurship in the U.S. Medical Device Industry Y1 - 2016 PB - Karlsruhe Institute of Technology CY - Karlsruhe ER - TY - CHAP A1 - Singh, Max Diamond ED - Schwegel, Philipp ED - Da-Cruz, Patrick ED - Hemel, Ulrich ED - Oberender, Peter T1 - Produktmanagement in der Medizintechnik T2 - Medizinprodukte Management N2 - Das Management in der Medizinprodukteindustrie steht vor vielfältigen Herausforderungen. So sinken einerseits die Produktpreise, anderseits wird auch für die kommenden Jahre in vielen Segmenten ein Mengenwachstum erwartet. Dies stellt die internen Prozesse, vom Customer Service bis hin zur Forschung & Entwicklung, auf den Prüfstand. Die Entscheidungsträger auf Kundenseite verändern sich, weg vom Produktanwender hin zu professionellen Einkaufsgemeinschaften mit immer größerer Verhandlungsmacht. Der hohe Internationalisierungsgrad der Unternehmen führt zu einer steigenden Komplexität bei der Implementierung von Marketing-, Vertriebs- und Produktentwicklungsstrategien auf Länderebene. Darüber hinaus werden zunehmend neue Geschäftsmodelle mit hohem Dienstleistungsanteil entwickelt, die mit der traditionellen Lieferantenrolle wenig zu tun haben und von Managern eine neue Fähigkeiten für die Umsetzung erfordern. Die Autoren des Sammelbands greifen die genannten Herausforderungen auf und bieten mit ihren Beiträgen Lösungsansätze, die sowohl für Manager im Medizinprodukteunternehmen als auch für Wissenschaftler und Studierende relevant sind. Y1 - 2014 SN - 978-3-941678-47-7 SP - 148 EP - 161 PB - PCO-Verlag CY - Bayreuth ER - TY - CHAP A1 - Singh, Max Diamond A1 - Capanni, Felix ED - Pfannstiel Mario A., ED - Da-Cruz, Patrick ED - Rasche, Christoph T1 - Medizintechnik-Spin-offs aus der Hochschule - Ein Prozessbeispiel T2 - Entrepreneurship im Gesundheitswesen II N2 - Die Aufmerksamkeit für Unternehmensgründungen hat in den letzten Jahren extrem zugenommen. Grundsätzlich muss ein Start-up in einem kompetitiven Umfeld erfolgreich sein, um bestehen zu können. Der Weg dorthin wird maßgeblich beeinflusst durch Planung und finanzielle Ressourcen, die die Gründer bereitstellen müssen. In der Medizinprodukteindustrie kommen zusätzlich große Hürden hinzu, die u. a. einen kurzen Produktlebenszyklus, lange Projektlaufzeiten, aufwendige klinische Studien und aktuell neue gesetzliche Verordnungen betreffen. Dieser Beitrag konzentriert sich zunächst auf mögliche Fördermittel und Beratung von Start-up-Projekten aus dem Hochschulbereich. Aus einer Analyse derzeit existierender Gründerwettbewerbe im Hinblick auf das Gesundheitswesen werden dem Leser entsprechende Adressen zum Einwerben von Fördermitteln geliefert. Darüber hinaus wird ein Pilot-Prozess vorgestellt, wie eine Ausgründungsberatung an der Hochschule Ulm im Studiengang Medizintechnik derzeit verläuft. Dies kann möglicherweise ein Anknüpfungspunkt für eine zukünftige Institutionalisierung von Spin-off-Vorhaben aus dem Hochschulbereich sein. Y1 - 2018 SN - 978-3-658-14781-5 SN - 978-3-658-14780-8 PB - Springer Gabler CY - Wiesbaden ER - TY - JOUR A1 - Singh, Max Diamond A1 - Russ, Jochen A1 - Terzidis, Orestis T1 - The Impact of the ObamaCare Excise Tax on Innovation and Entrepreneurship – Early Empirical Findings JF - International Journal of Innovation Science N2 - This study addresses aspects of governmental influence on innovation by analyzing the impact of the ObamaCare excise tax on the medical device industry. We initially give an overview of common approaches to measuring innovativeness and entrepreneurship, empirically assess whether existing metrics are suitable for investigating the innovation performance of the U.S. medical device industry, and define a new measure (firm innovation activity) for entrepreneurship. Then we perform a quantitative analysis to explore the impact of the tax. We analyze more than 60,000 product clearances from 1996 to 2013, using the FDA database. We find a significant relationship between product counts and revenues for one segment. Contrary to the present criticism of the excise tax, we find hardly any noteworthy response in either firm innovation activity or number of products launched in the year after the tax was introduced. The 2013 reduction of new product submissions is well within the limits of typical annual fluctuations observed in previous years. This provides a first indication that the excise tax act did not have a strong impact on innovative activities through the present. Y1 - 2015 U6 - https://doi.org/10.1260/1757-2223.7.2.75 VL - 7 IS - 2 SP - 75 EP - 90 PB - Emerald ER - TY - GEN A1 - Singh, Max Diamond A1 - Schlagintweit, S. A1 - Reischle, G. T1 - Additive-Manufactured Orthopedic Implants Under MDR Y1 - 2020 UR - https://www.odtmag.com/contents/view_online-exclusives/2020-08-11/additive-manufactured-orthopedic-implants-under-mdr/ IS - 08.11.20 ER - TY - JOUR A1 - Singh, Max Diamond A1 - Terzidis, O. T1 - Introducing Innovation Phase Transition JF - International Journal of Innovation Science N2 - Innovation diffusion points toward how innovations spread into the market after launch. This paper investigates diffusion dynamics at market entry time and proposes a new evolution pattern at the intersection between inventions and innovations. With this in mind, we initially prove that patent filings correlate with new product introductions in the U.S. spine market. Then we test our new theory supposing that certain patent filing threshold numbers accelerate strong economic returns in terms of innovations. We find that firms hitting certain patent filing thresholds significantly increase their product launches in the mentioned market. Moreover, the results seem to indicate that economic returns of inventions may be measured substantially. Thus, this paper suggests a new research area by utilizing our proposed concept about an Innovation Outcome Trigger Value (IOTV). Furthermore, the implications may also be interesting for practitioners, since we empirically prove that inventive activities turn out to be worthwhile, indeed. Y1 - 2015 U6 - https://doi.org/10.1108/IJIS-07-04-2015-B003 SN - 1757-2223 VL - 7 IS - 4 SP - 249 EP - 262 PB - Emerald ER - TY - CHAP A1 - Spreiter, G. A1 - Galibarov, Pavel E. A1 - Dendorfer, Sebastian A1 - Ferguson, Stephen J. T1 - Influence of kyphosis on spinal loading T2 - 10th International Symposium Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) Meeting, 11. - 14. April 2012, Berlin Y1 - 2012 ER - TY - JOUR A1 - Steiger, Tamara A1 - Foltan, Maik A1 - Philipp, Alois A1 - Mueller, Thomas A1 - Gruber, Michael Andreas A1 - Bredthauer, Andre A1 - Krenkel, Lars A1 - Birkenmaier, Clemens A1 - Lehle, Karla T1 - Accumulations of von Willebrand factor within ECMO oxygenators: Potential indicator of coagulation abnormalities in critically ill patients? JF - Artificial Organs N2 - Clot formation within membrane oxygenators (MOs) remains a critical problem during extracorporeal membrane oxygenation (ECMO). The composition of the clots-in particular, the presence of von Willebrand factor (vWF)-may be an indicator for prevalent nonphysiological flow conditions, foreign body reactions, or coagulation abnormalities in critically ill patients. Mats of interwoven gas exchange fibers from randomly collected MOs (PLS, Maquet, Rastatt, Germany) of 21 patients were stained with antibodies (anti-vWF and anti-P-selectin) and counterstained with 4 ',6-diamidino-2-phenylindole. The extent of vWF-loading was correlated with patient and technical data. While 12 MOs showed low vWF-loadings, 9 MOs showed high vWF-loading with highest accumulations close to crossing points of adjacent gas fibers. The presence and the extent of vWF-fibers/"cobwebs," leukocytes, platelet-leukocyte aggregates (PLAs), and P-selectin-positive platelet aggregates were independent of the extent of vWF-loading. However, the highly loaded MOs were obtained from patients with a significantly elevated SOFA score, severe thrombocytopenia, and persistent liver dysfunction. The coagulation abnormalities of these critically ill patients may cause an accumulation of the highly thrombogenic and elongated high-molecular-weight vWF multimers in the plasma which will be trapped in the MOs during the ECMO therapy. KW - ECMO KW - PLATELET ACTIVATION KW - THROMBOSIS KW - BLOOD FLOW KW - INFLAMMATION Y1 - 2019 U6 - https://doi.org/10.1111/aor.13513 SN - 1525-1594 VL - 43 IS - 11 SP - 1065 EP - 1076 PB - Wiley CY - Hoboken ER - TY - RPRT A1 - Steiger, Tamara A1 - Foltan, Maik A1 - Philipp, Alois A1 - Müller, Thomas A1 - Gruber, Michael Andreas A1 - Bredthauer, Andre A1 - Krenkel, Lars A1 - Birkenmaier, Clemens A1 - Lehle, Karla T1 - Accumulations of von Willebrand factor within ECMO oxygenators: Potential indicator of coagulation abnormalities in critically ill patients? N2 - Clot formation within membrane oxygenators (MOs) remains a critical problem during extracorporeal membrane oxygenation (ECMO). The composition of the clots—in particular, the presence of von Willebrand factor (vWF)—may be an indicator for prevalent nonphysiological flow conditions, foreign body reactions, or coagulation abnormalities in critically ill patients. Mats of interwoven gas exchange fibers from randomly collected MOs (PLS, Maquet, Rastatt, Germany) of 21 patients were stained with antibodies (anti‐vWF and anti‐P‐selectin) and counterstained with 4′,6‐diamidino‐2‐phenylindole. The extent of vWF‐loading was correlated with patient and technical data. While 12 MOs showed low vWF‐loadings, 9 MOs showed high vWF‐loading with highest accumulations close to crossing points of adjacent gas fibers. The presence and the extent of vWF‐fibers/“cobwebs,” leukocytes, platelet–leukocyte aggregates (PLAs), and P‐selectin‐positive platelet aggregates were independent of the extent of vWF‐loading. However, the highly loaded MOs were obtained from patients with a significantly elevated SOFA score, severe thrombocytopenia, and persistent liver dysfunction. The coagulation abnormalities of these critically ill patients may cause an accumulation of the highly thrombogenic and elongated high‐molecular‐weight vWF multimers in the plasma which will be trapped in the MOs during the ECMO therapy. Y1 - 2019 ER - TY - JOUR A1 - Stelzer, Vera A1 - Krenkel, Lars T1 - 2D numerical investigations derived from a 3D dragonfly wing captured with a high-resolution micro-CT JF - Technology and health care : official journal of the European Society for Engineering and Medicine N2 - BACKGROUND: Due to their corrugated profile, dragonfly wings have special aerodynamic characteristics during flying and gliding. OBJECTIVE: The aim of this study was to create a realistic 3D model of a dragonfly wing captured with a high-resolution micro-CT. To represent geometry changes in span and chord length and their aerodynamic effects, numerical investigations are carried out at different wing positions. METHODS: The forewing of a Camacinia gigantea was captured using a micro-CT. After the wing was adapted an error-free 3D model resulted. The wing was cut every 5 mm and 2D numerical analyses were conducted in Fluent® 2020 R2 (ANSYS, Inc., Canonsburg, PA, USA). RESULTS: The highest lift coefficient, as well as the highest lift-to-drag ratio, resulted at 0 mm and an angle of attack (AOA) of 5∘. At AOAs of 10∘ or 15∘, the flow around the wing stalled and a Kármán vortex street behind the wing becomes CONCLUSIONS: The velocity is higher on the upper side of the wing compared to the lower side. The pressure acts vice versa. Due to the recirculation zones that are formed in valleys of the corrugation pattern the wing resembles the form of an airfoil. KW - aerodynamics KW - computational fluid dynamics KW - Dragonfly wing KW - gliding flight KW - insect flight Y1 - 2022 U6 - https://doi.org/10.3233/THC-219010 N1 - Corresponding author: Vera Stelzer VL - 30 IS - 1 SP - 283 EP - 289 PB - IOS Press ER - TY - GEN A1 - Stelzer, Vera A1 - Rütten, Markus A1 - Krenkel, Lars T1 - Numerical Investigation of a 3D Dragonfly Wing Captured with a High-Resolution Micro-CT T2 - 8th European Congress on Computational Methods in Applied Sciences and Engineering, ECCOMAS Congress 2022, 5-9 June 2022, Oslo, Norway N2 - The special wing geometry of dragonflies consisting of veins and a membrane forming a corrugated profile leads to special aerodynamic characteristics. To capture the governing flow regimes of a dragonfly wing in detail, a realistic wing model has to be investigated. Therefore, this study aimed to analyze the aerodynamic characteristics of a 3D dragonfly wing reconstructed from a high-resolution micro-CT scan. Afterwards, a spatially high discretized mesh was generated using the mesh generator CENTAUR™ 14.5.0.2 (CentaurSoft, Austin, TX, US) to finally conduct Computational Fluid Dynamics (CFD) investigations in Fluent® 2020 R2 (ANSYS, Inc., Canonsburg, PA, US). Due to the small dimensions of the wing membrane, only the vein structure of a Camacinia Gigantea was captured at a micro-CT voxel size of 7 microns. The membrane was adapted and connected to the vein structure using a Boolean union operation. Occurring nconsistencies after combining the veins and the membrane were corrected using an adapted pymesh script [1]. As an initial study, only one quarter of the wing (outer wing section) was investigated to reduce the required computational effort. The resulting hybrid mesh consisting of 10 pseudo-structured prism layers along the wing surface and tetrahedra in the farfield area has 43 mio. nodes. The flow around the wing was considered to be incompressible and laminar using transient calculations. When the flow passes the vein structures, steady vortices occur in the corrugation valleys leading to recirculation zones. Therefore, the dragonfly wing resembles the profile of an airfoil. This leads to comparable lift coefficients of dragonfly wings and airfoil profiles at significantly reduced structural weight. The reconstructed geometry also included naturally occurring triangular prismlike serrated structures at the leading edge of the wing, which have comparable effects to micro vortex generators and might stabilize the recirculation zones. Further work aims to investigate the aerodynamic properties of a complete dragonfly wing during wing flapping. KW - CFD KW - Dragonfly KW - Aerodynamics KW - Gliding Flight Y1 - 2022 ER - TY - GEN A1 - Stelzer, Vera A1 - Tauwald, Sandra Melina A1 - Vielsmeier, Veronika A1 - Cieplik, Fabian A1 - Kandulski, Arne A1 - Schneider-Brachert, Wulf A1 - Wuensch, Olaf A1 - Rütten, Markus A1 - Krenkel, Lars T1 - Generation, Distribution, and Contagiousness of Surgical Smoke during Tracheotomies T2 - 23. DGLR Fach-Symposium Strömungen mit Ablösung, 09./10. November 2022, Berlin, Deutschland N2 - Surgical smoke has been a little discussed topic in the context of the current pandemic. Surgical smoke is generated during the cauterization of tissue with heat-generating devices and consists of 95% water vapor and 5% cellular debris in the form of particulate matter. In-vivo investigations are performed during tracheotomies where surgical smoke is produced during tissue electrocautery. Furthermore, in-vitro parametric studies to investigate the particle number and size distribution and the spatial distribution of surgical smoke with laser light sheet technique are conducted. The higher the power of the high-frequency-device the larger the particles in size and the higher the resulting particle counts. The images taken show the densest smoke at 40W with artificial saliva. The resulting characteristic size distribution, which may include viruses and bacterial components, confirms that the risk arising from surgical smoke should be considered. Furthermore, the experiments will provide the database for further numerical investigations. Y1 - 2022 UR - https://www.dlr.de/as/Portaldata/5/Resources/dokumente/veranstaltungen/stab_workshop/Jahresbericht2022.pdf CY - Göttingen ER - TY - CHAP A1 - Stelzer, Vera A1 - Tauwald, Sandra Melina A1 - Vielsmeier, Veronika A1 - Cieplik, Fabian A1 - Kandulski, Arne A1 - Schneider-Brachert, Wulf A1 - Wünsch, Olaf A1 - Rütten, Markus A1 - Krenkel, Lars ED - Dillman, Andreas ED - Heller, Gerd ED - Kraemer, Ewald ED - Wagner, Claus ED - Weiss, Julien T1 - Generation and Distribution of Surgical Smoke During High Frequency Electrocauterization T2 - New Results in Numerical and Experimental Fluid Mechanics XIV. STAB/DGLR Symposium 2022 N2 - Surgical Smoke is generated during the cauterization of tissue with high-frequency (HF) devices and consists of 95% water vapor and 5% cellular debris. When the coagulation tweezers, which are supplied with HF voltage by the HF device, touch tissue, the electric circuit is closed, and smoke is generated by the heat. In-vivo investigations are performed during tracheotomies where surgical smoke is produced during coagulation of tissue. Furthermore, in-vitro parametric studies to investigate the particle number and size distribution and the spatial distribution of surgical smoke with laser light sheet technique are conducted. With higher power of the HF device, the particles generated are larger in size and the total number of particles generated is also higher. Adding artificial saliva to the tissue shows even higher particle counts. The study by laser light sheet also confirms this. The resulting characteristic size distribution, which may include viruses and bacterial components, confirms considering the risk arising from surgical smoke. Furthermore, the experiments will provide the database for further numerical investigations. KW - Surgical smoke KW - Fluid Mechanics KW - Aerosols KW - Tracheotomies Y1 - 2023 SN - 978-3-031-40481-8 U6 - https://doi.org/10.1007/978-3-031-40482-5_53 SP - 559 EP - 568 PB - Springer Nature Switzerland AG CY - Cham, Switzerland ER - TY - CHAP A1 - Striegl, B. A1 - Kujat, Richard A1 - Dendorfer, Sebastian T1 - Quantitative analysis of cartilage surface by confocal laser scanning microscopy T2 - Biomedizinische Technik Y1 - 2014 U6 - https://doi.org/10.1515/bmt-2014-4012 VL - 59 IS - s1-A SP - 24 ER - TY - GEN A1 - Suess, Franz A1 - Melzner, Maximilian A1 - Dendorfer, Sebastian T1 - Towards Ergonomic working - machine learning algorithms and musculoskeletal modeling T2 - RIM 2021, 13th International Scientific Conference on Manufacturing Engineering, 29 Sept. - 1 Oct 2021, Sarajevo, Bosnia and Herzegovina Y1 - 2021 ER - TY - CHAP A1 - Suess, Franz A1 - Melzner, Maximilian A1 - Dendorfer, Sebastian T1 - Towards ergonomics working - machine learning algorithms and musculoskeletal modeling T2 - IOP Conference Series: Materials Science and Engineering N2 - Ergonomic workplaces lead to fewer work-related musculoskeletal disorders and thus fewer sick days. There are various guidelines to help avoid harmful situations. However, these recommendations are often rather crude and often neglect the complex interaction of biomechanical loading and psychological stress. This study investigates whether machine learning algorithms can be used to predict mechanical and stress-related muscle activity for a standardized motion. For this purpose, experimental data were collected for trunk movement with and without additional psychological stress. Two different algorithms (XGBoost and TensorFlow) were used to model the experimental data. XGBoost in particular predicted the results very well. By combining it with musculoskeletal models, the method shown here can be used for workplace analysis but also for the development of real-time feedback systems in real workplace environments. Y1 - 2021 U6 - https://doi.org/10.1088/1757-899X/1208/1/012001 SN - 1757-899X N1 - Corresponding author: Sebastian Dendorfer VL - 1208 PB - IOP Publishing ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Rasmussen, John A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - The influence of cognitive stress on muscle activation and spinal disc load T2 - European Society of Biomechanics meeting 2019, Vienna, Austria Y1 - 2019 UR - https://owncloud.tuwien.ac.at/index.php/s/dovqqcj02VeZHze ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - The influence of stress on spinal loading T2 - ESEM webconference, Dez. 2017 Y1 - 2016 ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - The influence of mental stress on spinal disc loading and muscle activity T2 - 23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017 Y1 - 2017 ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - Investigation of cognitive stress induced changes in spinal disc forces due to altered kinematics and muscle activity T2 - World Congress Biomechanics, Dublin, 2018 Y1 - 2018 ER - TY - CHAP A1 - Süß, Franz A1 - Putzer, Michael A1 - Dendorfer, Sebastian T1 - Numerische und experimentelle Untersuchungen an der Wirbelsäule T2 - Forschungssymposium Bad Abbach, Germany, 2015 Y1 - 2015 ER - TY - JOUR A1 - Tauwald, Sandra Melina A1 - Erzinger, Florian A1 - Quadrio, Maurizio A1 - Rütten, Markus A1 - Stemmer, Christian A1 - Krenkel, Lars T1 - Tomo-PIV in a patient-specific model of human nasal cavities: a methodological approach JF - Measurement Science and Technology N2 - The human nose serves as the primary gateway for air entering the respiratory system and plays a vital role in breathing. Nasal breathing difficulties are a significant health concern, leading to substantial healthcare costs for patients. Understanding nasal airflow dynamics is crucial for comprehending respiratory mechanisms. This article presents a detailed study using tomo-Particle Image Velocimetry (PIV) to investigate nasal airflow dynamics while addressing its accuracy. Embedded in the OpenNose project, the work described aims to provide a validation basis for different numerical approaches to upper airway flow. The study includes the manufacturing of a transparent silicone model based on a clinical CT scan, refractive index matching to minimize optical distortions, and precise flow rate adjustments based on physiological breathing cycles. This method allows for spatial high-resolution investigations in different regions of interest within the nasopharynx during various phases of the breathing cycle. The results demonstrate the accuracy of the investigations, enabling detailed analysis of flow structures and gradients. This spatial high-resolution tomo-PIV approach provides valuable insights into the complex flow phenomena occurring during the physiological breathing cycle in the nasopharynx. The study's findings contribute to advancements in non-free-of-sight experimental flow investigation of complex cavities under nearly realistic conditions. Furthermore, reliable and accurate experimental data is crucial for properly validating numerical approaches that compute this patient-specific flow for clinical purposes. Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-70393 N1 - Corresponding author: Sandra Melina Tauwald VL - 35 IS - 5 PB - IOP Publishing ER - TY - GEN A1 - Tauwald, Sandra Melina A1 - Krenkel, Lars T1 - Elementary experimental setup for flow visualization in upper human respiratory tract T2 - 25th Congress of the European Society of Biomechanics, July 7-10, 2019, Vienna, Austria Y1 - 2019 UR - https://esbiomech.org/conference/archive/2019vienna/Contribution_195.pdf ER - TY - JOUR A1 - Tauwald, Sandra Melina A1 - Michel, Johanna A1 - Brandt, Marie A1 - Vielsmeier, Veronika A1 - Stemmer, Christian A1 - Krenkel, Lars T1 - Experimental studies and mathematical modeling of the viscoelastic rheology of tracheobronchial mucus from respiratory healthy patients JF - Multidisciplinary Respiratory Medicine N2 - BACKGROUND: Tracheobronchial mucus plays a crucial role in pulmonary function by providing protection against inhaled pathogens. Due to its composition of water, mucins, and other biomolecules, it has a complex viscoelastic rheological behavior. This interplay of both viscous and elastic properties has not been fully described yet. In this study, we characterize the rheology of human mucus using oscillatory and transient tests. Based on the transient tests, we describe the material behavior of mucus under stress and strain loading by mathematical models. METHODS: Mucus samples were collected from clinically used endotracheal tubes. For rheological characterization, oscillatory amplitude-sweep and frequency-sweep tests, and transient creep-recovery and stress-relaxation tests were performed. The results of the transient test were approximated using the Burgers model, the Weibull distribution, and the six-element Maxwell model. The three-dimensional microstructure of the tracheobronchial mucus was visualized using scanning electron microscope imaging. RESULTS: Amplitude-sweep tests showed storage moduli ranging from 0.1 Pa to 10000 Pa and a median critical strain of 4 %. In frequency-sweep tests, storage and loss moduli increased with frequency, with the median of the storage modulus ranging from 10 Pa to 30 Pa, and the median of the loss modulus from 5 Pa to 14 Pa. The Burgers model approximates the viscoelastic behavior of tracheobronchial mucus during a constant load of stress appropriately (R2 of 0.99), and the Weibull distribution is suitable to predict the recovery of the sample after the removal of this stress (R2 of 0.99). The approximation of the stress-relaxation test data by a six-element Maxwell model shows a larger fit error (R2 of 0.91). CONCLUSIONS: This study provides a detailed description of all process steps of characterizing the rheology of tracheobronchial mucus, including sample collection, microstructure visualization, and rheological investigation. Based on this characterization, we provide mathematical models of the rheological behavior of tracheobronchial mucus. These can now be used to simulate mucus flow in the respiratory system through numerical approaches. KW - tracheobronchial mucus KW - rheological model KW - viscoelasticity Y1 - 2023 U6 - https://doi.org/10.4081/mrm.2023.923 SN - 2049-6958 N1 - Corresponding author: Sandra Melina Tauwald VL - 18 IS - 1 PB - PAGEPress CY - Pavia, Italy ER - TY - GEN A1 - Tauwald, Sandra Melina A1 - Quadrio, Maurizio A1 - Rütten, Markus A1 - Stemmer, Christian A1 - Krenkel, Lars T1 - High Spatial Resolution Tomo-PIV of the Nasopharynx Focussing on the Physiological Breathing Cycle T2 - 23. DGLR Fach-Symposium Strömungen mit Ablösung, 09./10. November 2022, Berlin, Deutschland N2 - 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. KW - Tomographic PIV KW - Flow visualisation KW - Physiological Breathing KW - Nasal airflow Y1 - 2022 UR - https://www.dlr.de/as/Portaldata/5/Resources/dokumente/veranstaltungen/stab_workshop/Jahresbericht2022.pdf CY - Göttingen ER - TY - CHAP A1 - Tauwald, Sandra Melina A1 - Quadrio, Maurizio A1 - Rütten, Markus A1 - Stemmer, Christian A1 - Krenkel, Lars T1 - High Spatial Resolution Tomo-PIV of the Trachea Focussing on the Physiological Breathing Cycle T2 - New Results in Numerical and Experimental Fluid Mechanics XIV - Contributions to the 23nd STAB/DGLR Symposium N2 - 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. KW - Tomographic PIV KW - Flow visualisation KW - Breathing cycle KW - Nasal airflow Y1 - 2023 N1 - Accepted for publication, not yet published PB - Springer ER -