TY - JOUR A1 - Heel, Mareike van A1 - Dikta, Gerhard A1 - Braekers, Roel T1 - Bootstrap based goodness‑of‑fit tests for binary multivariate regression models JF - Journal of the Korean Statistical Society N2 - We consider a binary multivariate regression model where the conditional expectation of a binary variable given a higher-dimensional input variable belongs to a parametric family. Based on this, we introduce a model-based bootstrap (MBB) for higher-dimensional input variables. This test can be used to check whether a sequence of independent and identically distributed observations belongs to such a parametric family. The approach is based on the empirical residual process introduced by Stute (Ann Statist 25:613–641, 1997). In contrast to Stute and Zhu’s approach (2002) Stute & Zhu (Scandinavian J Statist 29:535–545, 2002), a transformation is not required. Thus, any problems associated with non-parametric regression estimation are avoided. As a result, the MBB method is much easier for users to implement. To illustrate the power of the MBB based tests, a small simulation study is performed. Compared to the approach of Stute & Zhu (Scandinavian J Statist 29:535–545, 2002), the simulations indicate a slightly improved power of the MBB based method. Finally, both methods are applied to a real data set. Y1 - 2021 U6 - https://doi.org/10.1007/s42952-021-00142-4 SN - 2005-2863 (Online) SN - 1226-3192 (Print) N1 - Corresponding author: Mareike van Heel VL - 51 PB - Springer Nature CY - Singapur ER - TY - CHAP A1 - Klöser, Lars A1 - Kohl, Philipp A1 - Kraft, Bodo A1 - Zündorf, Albert T1 - Multi-attribute relation extraction (MARE): simplifying the application of relation extraction T2 - Proceedings of the 2nd International Conference on Deep Learning Theory and Applications DeLTA - Volume 1 N2 - Natural language understanding’s relation extraction makes innovative and encouraging novel business concepts possible and facilitates new digitilized decision-making processes. Current approaches allow the extraction of relations with a fixed number of entities as attributes. Extracting relations with an arbitrary amount of attributes requires complex systems and costly relation-trigger annotations to assist these systems. We introduce multi-attribute relation extraction (MARE) as an assumption-less problem formulation with two approaches, facilitating an explicit mapping from business use cases to the data annotations. Avoiding elaborated annotation constraints simplifies the application of relation extraction approaches. The evaluation compares our models to current state-of-the-art event extraction and binary relation extraction methods. Our approaches show improvement compared to these on the extraction of general multi-attribute relations. Y1 - 2021 SN - 978-989-758-526-5 U6 - https://doi.org/10.5220/0010559201480156 N1 - 2nd International Conference on Deep Learning Theory and Applications, DeLTA2021, July 7-9, 2021 SP - 148 EP - 156 PB - SciTePress CY - Setúbal ER - TY - CHAP A1 - Kohl, Philipp A1 - Schmidts, Oliver A1 - Klöser, Lars A1 - Werth, Henri A1 - Kraft, Bodo A1 - Zündorf, Albert T1 - STAMP 4 NLP – an agile framework for rapid quality-driven NLP applications development T2 - Quality of Information and Communications Technology. QUATIC 2021 N2 - The progress in natural language processing (NLP) research over the last years, offers novel business opportunities for companies, as automated user interaction or improved data analysis. Building sophisticated NLP applications requires dealing with modern machine learning (ML) technologies, which impedes enterprises from establishing successful NLP projects. Our experience in applied NLP research projects shows that the continuous integration of research prototypes in production-like environments with quality assurance builds trust in the software and shows convenience and usefulness regarding the business goal. We introduce STAMP 4 NLP as an iterative and incremental process model for developing NLP applications. With STAMP 4 NLP, we merge software engineering principles with best practices from data science. Instantiating our process model allows efficiently creating prototypes by utilizing templates, conventions, and implementations, enabling developers and data scientists to focus on the business goals. Due to our iterative-incremental approach, businesses can deploy an enhanced version of the prototype to their software environment after every iteration, maximizing potential business value and trust early and avoiding the cost of successful yet never deployed experiments. KW - Machine learning KW - Process model KW - Natural language processing Y1 - 2021 SN - 978-3-030-85346-4 SN - 978-3-030-85347-1 U6 - https://doi.org/10.1007/978-3-030-85347-1_12 N1 - International Conference on the Quality of Information and Communications Technology, QUATIC 2021, 8-11 September, Algarve, Portugal SP - 156 EP - 166 PB - Springer CY - Cham ER - TY - CHAP A1 - Schmidts, Oliver A1 - Kraft, Bodo A1 - Winkens, Marvin A1 - Zündorf, Albert T1 - Catalog integration of heterogeneous and volatile product data T2 - DATA 2020: Data Management Technologies and Applications N2 - The integration of frequently changing, volatile product data from different manufacturers into a single catalog is a significant challenge for small and medium-sized e-commerce companies. They rely on timely integrating product data to present them aggregated in an online shop without knowing format specifications, concept understanding of manufacturers, and data quality. Furthermore, format, concepts, and data quality may change at any time. Consequently, integrating product catalogs into a single standardized catalog is often a laborious manual task. Current strategies to streamline or automate catalog integration use techniques based on machine learning, word vectorization, or semantic similarity. However, most approaches struggle with low-quality or real-world data. We propose Attribute Label Ranking (ALR) as a recommendation engine to simplify the integration process of previously unknown, proprietary tabular format into a standardized catalog for practitioners. We evaluate ALR by focusing on the impact of different neural network architectures, language features, and semantic similarity. Additionally, we consider metrics for industrial application and present the impact of ALR in production and its limitations. Y1 - 2021 SN - 978-3-030-83013-7 U6 - https://doi.org/10.1007/978-3-030-83014-4_7 N1 - International Conference on Data Management Technologies and Applications, DATA 2020, 7-9 July SP - 134 EP - 153 PB - Springer CY - Cham ER - TY - JOUR A1 - Jahnke, Siegfried A1 - Roussel, Johanna A1 - Hombach, Thomas A1 - Kochs, Johannes A1 - Fischbach, Andreas A1 - Huber, Gregor A1 - Scharr, Hanno T1 - phenoSeeder - A robot system for automated handling and phenotyping of individual seeds JF - Plant physiology N2 - The enormous diversity of seed traits is an intriguing feature and critical for the overwhelming success of higher plants. In particular, seed mass is generally regarded to be key for seedling development but is mostly approximated by using scanning methods delivering only two-dimensional data, often termed seed size. However, three-dimensional traits, such as the volume or mass of single seeds, are very rarely determined in routine measurements. Here, we introduce a device named phenoSeeder, which enables the handling and phenotyping of individual seeds of very different sizes. The system consists of a pick-and-place robot and a modular setup of sensors that can be versatilely extended. Basic biometric traits detected for individual seeds are two-dimensional data from projections, three-dimensional data from volumetric measures, and mass, from which seed density is also calculated. Each seed is tracked by an identifier and, after phenotyping, can be planted, sorted, or individually stored for further evaluation or processing (e.g. in routine seed-to-plant tracking pipelines). By investigating seeds of Arabidopsis (Arabidopsis thaliana), rapeseed (Brassica napus), and barley (Hordeum vulgare), we observed that, even for apparently round-shaped seeds of rapeseed, correlations between the projected area and the mass of seeds were much weaker than between volume and mass. This indicates that simple projections may not deliver good proxies for seed mass. Although throughput is limited, we expect that automated seed phenotyping on a single-seed basis can contribute valuable information for applications in a wide range of wild or crop species, including seed classification, seed sorting, and assessment of seed quality. Y1 - 2016 U6 - https://doi.org/10.1104/pp.16.01122 SN - 0032-0889 VL - 172 IS - 3 SP - 1358 EP - 1370 PB - Oxford University Press CY - Oxford ER - TY - GEN A1 - Schreiber, Marc T1 - Mit Maximum-Entropie das Parsing natürlicher Sprache erlernen N2 - Für die Verarbeitung von natürlicher Sprache ist ein wichtiger Zwischenschritt das Parsing, bei dem für Sätze der natürlichen Sprache Ableitungsbäume bestimmt werden. Dieses Verfahren ist vergleichbar zum Parsen formaler Sprachen, wie z. B. das Parsen eines Quelltextes. Die Parsing-Methoden der formalen Sprachen, z. B. Bottom-up-Parser, können nicht auf das Parsen der natürlichen Sprache übertragen werden, da keine Formalisierung der natürlichen Sprachen existiert [3, 12, 23, 30]. In den ersten Programmen, die natürliche Sprache verarbeiten [32, 41], wurde versucht die natürliche Sprache mit festen Regelmengen zu verarbeiten. Dieser Ansatz stieß jedoch schnell an seine Grenzen, da die Regelmenge nicht vollständig sowie nicht minimal ist und wegen der benötigten Menge an Regeln schwer zu verwalten ist. Die Korpuslinguistik [22] bot die Möglichkeit, die Regelmenge durch Supervised-Machine-Learning-Verfahren [2] abzulösen. Teil der Korpuslinguistik ist es, große Textkorpora zu erstellen und diese mit sprachlichen Strukturen zu annotieren. Zu diesen Strukturen gehören sowohl die Wortarten als auch die Ableitungsbäume der Sätze. Vorteil dieser Methodik ist es, dass repräsentative Daten zur Verfügung stehen. Diese Daten werden genutzt, um mit Supervised-Machine-Learning-Verfahren die Gesetzmäßigkeiten der natürliche Sprachen zu erlernen. Das Maximum-Entropie-Verfahren ist ein Supervised-Machine-Learning-Verfahren, das genutzt wird, um natürliche Sprache zu erlernen. Ratnaparkhi [25] nutzt Maximum-Entropie, um Ableitungsbäume für Sätze der natürlichen Sprache zu erlernen. Dieses Verfahren macht es möglich, die natürliche Sprache (abgebildet als Σ∗) trotz einer fehlenden formalen Grammatik zu parsen. Y1 - 2016 N1 - Aufsatz zu einem Seminar (Theoretische Informatik) an der FH Aachen, 2016. PB - FH Aachen CY - Aachen ER - TY - JOUR A1 - Lanzl, I. A1 - Kotliar, Konstantin T1 - Können Anti-VEGF-Injektionen Glaukom oder okuläre Hypertension verursachen? T1 - Can Anti-VEGF Injections Cause Glaucoma or Ocular Hypertension? JF - Klinische Monatsblätter für Augenheilkunde Y1 - 2017 U6 - https://doi.org/10.1055/s-0043-101819 SN - 0023-2165 VL - 234 IS - 2 SP - 191 EP - 193 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Zange, Jochen A1 - Schopen, Kathrin A1 - Albracht, Kirsten A1 - Gerlach, Darius A. A1 - Frings-Meuthen, Petra A1 - Maffiuletti, Nicola A. A1 - Bloch, Wilhelm A1 - Rittweger, Jörn T1 - Using the Hephaistos orthotic device to study countermeasure effectiveness of neuromuscular electrical stimulation and dietary lupin protein supplementation, a randomised controlled trial JF - Plos one Y1 - 2017 U6 - https://doi.org/10.1371/journal.pone.0171562 VL - 12 IS - 2 ER - TY - CHAP A1 - Goldmann, Jan-Peter A1 - Braunstein, Bjoern A1 - Heinrich, Kai A1 - Sanno, Maximilian A1 - Stäudle, Benjamin A1 - Ritzdorf, Wolfgang A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Joint work of the take-off leg during elite high jump T2 - Proceedings of the 33th International Conference on Biomechanics in Sports (ISBS) Y1 - 2015 ER - TY - CHAP A1 - Droszez, Anna A1 - Sanno, Maximilian A1 - Goldmann, Jan-Peter A1 - Albracht, Kirsten A1 - Brüggemann, Gerd-Peter A1 - Braunstein, Bjoern T1 - Differences between take-off behavior during vertical jumps and two artistic elements T2 - 34th International Conference of Biomechanics in Sport, Tsukuba, Japan, July 18-22, 2016 Y1 - 2016 SN - 1999-4168 SP - 577 EP - 580 ER - TY - CHAP A1 - Abel, Thomas A1 - Bonin, Dominik A1 - Albracht, Kirsten A1 - Zeller, Sebastian A1 - Brüggemann, Gert-Peter A1 - Burkett, Brendan A1 - Strüder, Heiko K. T1 - Kinematic profile of the elite handcyclist T2 - 28th International Conference on Biomechanics in Sports, Marquette, Michigan, USA, July 19 – 23, 2010 Y1 - 2017 SN - 1999-4168 SP - 140 EP - 141 ER - TY - CHAP A1 - Braunstein, Bjoern A1 - Goldmann, Jan-Peter A1 - Albracht, Kirsten A1 - Sanno, Maximilian A1 - Willwacher, Steffen A1 - Heinrich, Kai A1 - Herrmann, Volker A1 - Brüggemann, Gert-Peter T1 - Joint specific contribution of mechanical power and work during acceleration and top speed in elite sprinters T2 - 31 International Conference on Biomechanics in Sports, Taipei, Taiwan, July 07 - July 22, 2013 Y1 - 2013 SN - 1999-4168 ER - TY - THES A1 - Albracht, Kirsten T1 - Influence of mechanical properties of the leg extensor muscletendon units on running economy Y1 - 2010 N1 - Cologne, German Sport Univ., Diss., 2010 PB - Deutsche Sporthochschule Köln CY - Köln ER - TY - JOUR A1 - Kolditz, Melanie A1 - Albin, Thivaharan A1 - Brüggemann, Gert-Peter A1 - Abel, Dirk A1 - Albracht, Kirsten T1 - Robotergestütztes System für ein verbessertes neuromuskuläres Aufbautraining der Beinstrecker JF - at - Automatisierungstechnik N2 - Neuromuskuläres Aufbautraining der Beinstrecker ist ein wichtiger Bestandteil in der Rehabilitation und Prävention von Muskel-Skelett-Erkrankungen. Effektives Training erfordert hohe Muskelkräfte, die gleichzeitig hohe Belastungen von bereits geschädigten Strukturen bedeuten. Um trainingsinduzierte Schädigungen zu vermeiden, müssen diese Kräfte kontrolliert werden. Mit heutigen Trainingsgeräten können diese Ziele allerdings nicht erreicht werden. Für ein sicheres und effektives Training sollen durch den Einsatz der Robotik, Sensorik, eines Regelkreises sowie Muskel-Skelett-Modellen Belastungen am Zielgewebe direkt berechnet und kontrolliert werden. Auf Basis zweier Vorstudien zu möglichen Stellgrößen wird der Aufbau eines robotischen Systems vorgestellt, das sowohl für Forschungszwecke als auch zur Entwicklung neuartiger Trainingsgeräte verwendet werden kann. Y1 - 2016 U6 - https://doi.org/10.1515/auto-2016-0044 SN - 2196-677X VL - 64 IS - 11 SP - 905 EP - 914 PB - De Gruyter CY - Berlin ER - TY - CHAP A1 - Kolditz, Melanie A1 - Albracht, Kirsten A1 - Fasse, Alessandro A1 - Albin, Thivaharan A1 - Brüggemann, Gert-Peter A1 - Abel, Dirk T1 - Evaluation of an industrial robot as a leg press training device T2 - XV International Symposium on Computer Simulation in Biomechanics July 9th – 11th 2015, Edinburgh, UK Y1 - 2015 SP - 41 EP - 42 ER - TY - CHAP A1 - Kolditz, Melanie A1 - Albin, Thivaharan A1 - Fasse, Alessandro A1 - Brüggemann, Gert-Peter A1 - Abel, Dirk A1 - Albracht, Kirsten T1 - Simulative Analysis of Joint Loading During Leg Press Exercise for Control Applications T2 - IFAC-PapersOnLine Y1 - 2015 U6 - https://doi.org/10.1016/j.ifacol.2015.10.179 N1 - IFAC-PapersOnLine 48-20; Conference Paper Archive VL - 48 IS - 20 SP - 435 EP - 440 ER - TY - CHAP A1 - Behbahani, Mehdi A1 - Rible, Sebastian A1 - Moulinec, Charles A1 - Fournier, Yvan A1 - Nicolai, Mike A1 - Crosetto, Paolo T1 - Simulation of the FDA Centrifugal Blood Pump Using High Performance Computing T2 - World Academy of Science, Engineering and Technology International Journal of Mechanical and Mechatronics Engineering Y1 - 2015 VL - 9 IS - 5 ER - TY - JOUR A1 - Jildeh, Zaid B. A1 - Wagner, Patrick H. A1 - Schöning, Michael Josef T1 - Sterilization of Objects, Products, and Packaging Surfaces and Their Characterization in Different Fields of Industry: The Status in 2020 JF - physica status solidi (a) applications and materials science N2 - The treatment method to deactivate viable microorganisms from objects or products is termed sterilization. There are multiple forms of sterilization, each intended to be applied for a specific target, which depends on—but not limited to—the thermal, physical, and chemical stability of that target. Herein, an overview on the currently used sterilization processes in the global market is provided. Different sterilization techniques are grouped under a category that describes the method of treatment: radiation (gamma, electron beam, X-ray, and ultraviolet), thermal (dry and moist heat), and chemical (ethylene oxide, ozone, chlorine dioxide, and hydrogen peroxide). For each sterilization process, the typical process parameters as defined by regulations and the mode of antimicrobial activity are summarized. Finally, the recommended microorganisms that are used as biological indicators to validate sterilization processes in accordance with the rules that are established by various regulatory agencies are summarized. KW - bioburdens KW - sterility tests KW - sterilization efficacy KW - sterilization methods KW - validation methods Y1 - 2021 U6 - https://doi.org/10.1002/pssa.202000732 SN - 1862-6319 N1 - Corresponding author: Michael J. Schöning VL - 218 IS - 13 PB - Wiley-VCH CY - Weinheim ER - TY - THES A1 - Bayer, Robin T1 - Development of a novel in-vitro vascular model for determination of physiological and pathophysiological mechanobiology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:38-362212 N1 - Dissertation, Universität zu Köln, 2021 PB - Universität zu Köln CY - Köln ER - TY - JOUR A1 - Molinnus, Denise A1 - Drinic, Aleksander A1 - Iken, Heiko A1 - Kröger, Nadja A1 - Zinser, Max A1 - Smeets, Ralf A1 - Köpf, Marius A1 - Kopp, Alexander A1 - Schöning, Michael Josef T1 - Towards a flexible electrochemical biosensor fabricated from biocompatible Bombyx mori silk JF - Biosensors and Bioelectronics Y1 - 2021 U6 - https://doi.org/10.1016/j.bios.2021.113204 SN - 0956-5663 VL - 183 IS - Art. 113204 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Yoshinobu, Tatsuo A1 - Schöning, Michael Josef T1 - Light-addressable potentiometric sensors (LAPS) for cell monitoring and biosensing JF - Current Opinion in Electrochemistry Y1 - 2021 U6 - https://doi.org/10.1016/j.coelec.2021.100727 SN - 2451-9103 IS - In Press, Journal Pre-proof PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wert, Stefan A1 - Iken, Heiko A1 - Schöning, Michael Josef A1 - Matysik, Frank-Michael T1 - Development of a temperature‐pulse enhanced electrochemical glucose biosensor and characterization of its stability via scanning electrochemical microscopy JF - Electroanalysis N2 - Glucose oxidase (GOx) is an enzyme frequently used in glucose biosensors. As increased temperatures can enhance the performance of electrochemical sensors, we investigated the impact of temperature pulses on GOx that was drop-coated on flattened Pt microwires. The wires were heated by an alternating current. The sensitivity towards glucose and the temperature stability of GOx was investigated by amperometry. An up to 22-fold increase of sensitivity was observed. Spatially resolved enzyme activity changes were investigated via scanning electrochemical microscopy. The application of short (<100 ms) heat pulses was associated with less thermal inactivation of the immobilized GOx than long-term heating. Y1 - 2021 U6 - https://doi.org/10.1002/elan.202100089 SN - 1521-4109 IS - Early View PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Waldvogel, Janice A1 - Ritzmann, Ramona A1 - Freyler, Kathrin A1 - Helm, Michael A1 - Monti, Elena A1 - Albracht, Kirsten A1 - Stäudle, Benjamin A1 - Gollhofer, Albert A1 - Narici, Marco T1 - The Anticipation of Gravity in Human Ballistic Movement JF - Frontiers in Physiology N2 - Stretch-shortening type actions are characterized by lengthening of the pre-activated muscle-tendon unit (MTU) in the eccentric phase immediately followed by muscle shortening. Under 1 g, pre-activity before and muscle activity after ground contact, scale muscle stiffness, which is crucial for the recoil properties of the MTU in the subsequent push-off. This study aimed to examine the neuro-mechanical coupling of the stretch-shortening cycle in response to gravity levels ranging from 0.1 to 2 g. During parabolic flights, 17 subjects performed drop jumps while electromyography (EMG) of the lower limb muscles was combined with ultrasound images of the gastrocnemius medialis, 2D kinematics and kinetics to depict changes in energy management and performance. Neuro-mechanical coupling in 1 g was characterized by high magnitudes of pre-activity and eccentric muscle activity allowing an isometric muscle behavior during ground contact. EMG during pre-activity and the concentric phase systematically increased from 0.1 to 1 g. Below 1 g the EMG in the eccentric phase was diminished, leading to muscle lengthening and reduced MTU stretches. Kinetic energy at take-off and performance were decreased compared to 1 g. Above 1 g, reduced EMG in the eccentric phase was accompanied by large MTU and muscle stretch, increased joint flexion amplitudes, energy loss and reduced performance. The energy outcome function established by linear mixed model reveals that the central nervous system regulates the extensor muscles phase- and load-specifically. In conclusion, neuro-mechanical coupling appears to be optimized in 1 g. Below 1 g, the energy outcome is compromised by reduced muscle stiffness. Above 1 g, loading progressively induces muscle lengthening, thus facilitating energy dissipation. Y1 - 2021 U6 - https://doi.org/10.3389/fphys.2021.614060 SN - 1664-042X PB - Frontiers CY - Lausanne ER - TY - JOUR A1 - Hugenroth, Kristin A1 - Neidlin, Michael A1 - Engelmann, Ulrich M. A1 - Kaufmann, Tim A. S. A1 - Steinseifer, Ulrich A1 - Heilmann, Torsten T1 - Tipless Transseptal Cannula Concept Combines Improved Hemodynamic Properties and Risk‐Reduced Placement: an In Silico Proof‐of‐Concept JF - Artificial Organs Y1 - 2021 U6 - https://doi.org/10.1111/aor.13964 SN - 1525-1594 IS - Accepted Article PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Morat, Mareike A1 - Faude, Oliver A1 - Hanssen, Henner A1 - Ludyga, Sebastian A1 - Zacher, Jonas A1 - Eibl, Angi A1 - Albracht, Kirsten A1 - Donath, Lars T1 - Agility Training to Integratively Promote Neuromuscular, Cognitive, Cardiovascular and Psychosocial Function in Healthy Older Adults: A Study Protocol of a One-Year Randomized-Controlled Trial JF - International Journal of Environmental Research and Public Health N2 - Exercise training effectively mitigates aging-induced health and fitness impairments. Traditional training recommendations for the elderly focus separately on relevant physiological fitness domains, such as balance, flexibility, strength and endurance. Thus, a more holistic and functional training framework is needed. The proposed agility training concept integratively tackles spatial orientation, stop and go, balance and strength. The presented protocol aims at introducing a two-armed, one-year randomized controlled trial, evaluating the effects of this concept on neuromuscular, cardiovascular, cognitive and psychosocial health outcomes in healthy older adults. Eighty-five participants were enrolled in this ongoing trial. Seventy-nine participants completed baseline testing and were block-randomized to the agility training group or the inactive control group. All participants undergo pre- and post-testing with interim assessment after six months. The intervention group currently receives supervised, group-based agility training twice a week over one year, with progressively demanding perceptual, cognitive and physical exercises. Knee extension strength, reactive balance, dual task gait speed and the Agility Challenge for the Elderly (ACE) serve as primary endpoints and neuromuscular, cognitive, cardiovascular, and psychosocial meassures serve as surrogate secondary outcomes. Our protocol promotes a comprehensive exercise training concept for older adults, that might facilitate stakeholders in health and exercise to stimulate relevant health outcomes without relying on excessively time-consuming physical activity recommendations. KW - agility KW - prevention KW - healthy aging KW - community dwelling KW - psychosocial Y1 - 2020 U6 - https://doi.org/10.3390/ijerph17061853 SN - 1660-4601 VL - 17 IS - 6 SP - 1 EP - 14 PB - MDPI CY - Basel ER - TY - JOUR A1 - Givanoudi, Stella A1 - Cornelis, Peter A1 - Rasschaert, Geertrui A1 - Wackers, Gideon A1 - Iken, Heiko A1 - Rolka, David A1 - Yongabi, Derick A1 - Robbens, Johan A1 - Schöning, Michael Josef A1 - Heyndrickx, Marc A1 - Wagner, Patrick T1 - Selective Campylobacter detection and quantification in poultry: A sensor tool for detecting the cause of a common zoonosis at its source JF - Sensors and Actuators B: Chemical Y1 - 2021 U6 - https://doi.org/10.1016/j.snb.2021.129484 SN - 0925-4005 IS - In Press, Journal Pre-proof SP - Article 129484 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Malinowski, Daniel A1 - Fournier, Yvan A1 - Horbach, Andreas A1 - Frick, Michael A1 - Magliani, Mirko A1 - Kalverkamp, Sebastian A1 - Hildinger, Martin A1 - Spillner, Jan A1 - Behbahani, Mehdi A1 - Hima, Flutura T1 - Computational fluid dynamics analysis of endoluminal aortic perfusion JF - Perfusion N2 - Introduction: In peripheral percutaneous (VA) extracorporeal membrane oxygenation (ECMO) procedures the femoral arteries perfusion route has inherent disadvantages regarding poor upper body perfusion due to watershed. With the advent of new long flexible cannulas an advancement of the tip up to the ascending aorta has become feasible. To investigate the impact of such long endoluminal cannulas on upper body perfusion, a Computational Fluid Dynamics (CFD) study was performed considering different support levels and three cannula positions. Methods: An idealized literature-based- and a real patient proximal aortic geometry including an endoluminal cannula were constructed. The blood flow was considered continuous. Oxygen saturation was set to 80% for the blood coming from the heart and to 100% for the blood leaving the cannula. 50% and 90% venoarterial support levels from the total blood flow rate of 6 l/min were investigated for three different positions of the cannula in the aortic arch. Results: For both geometries, the placement of the cannula in the ascending aorta led to a superior oxygenation of all aortic blood vessels except for the left coronary artery. Cannula placements at the aortic arch and descending aorta could support supra-aortic arteries, but not the coronary arteries. All positions were able to support all branches with saturated blood at 90% flow volume. Conclusions: In accordance with clinical observations CFD analysis reveals, that retrograde advancement of a long endoluminal cannula can considerably improve the oxygenation of the upper body and lead to oxygen saturation distributions similar to those of a central cannulation. KW - computational fluid dynamics analysis KW - simulation KW - endoluminal KW - aortic perfusion KW - extracorporeal membrane oxygenation Y1 - 2022 U6 - https://doi.org/10.1177/02676591221099809 SN - 1477-111X VL - 0 IS - 0 SP - 1 EP - 8 PB - Sage CY - London ER - TY - JOUR A1 - Lenz, Maximilian A1 - Kahmann, Stephanie Lucina A1 - Behbahani, Mehdi A1 - Pennig, Lenhard A1 - Hackl, Michael A1 - Leschinger, Tim A1 - Müller, Lars Peter A1 - Wegmann, Kilian T1 - Influence of rotator cuff preload on fracture configuration in proximal humerus fractures: a proof of concept for fracture simulation JF - Archives of Orthopaedic and Trauma Surgery N2 - Introduction In regard of surgical training, the reproducible simulation of life-like proximal humerus fractures in human cadaveric specimens is desirable. The aim of the present study was to develop a technique that allows simulation of realistic proximal humerus fractures and to analyse the influence of rotator cuff preload on the generated lesions in regards of fracture configuration. Materials and methods Ten cadaveric specimens (6 left, 4 right) were fractured using a custom-made drop-test bench, in two groups. Five specimens were fractured without rotator cuff preload, while the other five were fractured with the tendons of the rotator cuff preloaded with 2 kg each. The humeral shaft and the shortened scapula were potted. The humerus was positioned at 90° of abduction and 10° of internal rotation to simulate a fall on the elevated arm. In two specimens of each group, the emergence of the fractures was documented with high-speed video imaging. Pre-fracture radiographs were taken to evaluate the deltoid-tuberosity index as a measure of bone density. Post-fracture X-rays and CT scans were performed to define the exact fracture configurations. Neer’s classification was used to analyse the fractures. Results In all ten cadaveric specimens life-like proximal humerus fractures were achieved. Two III-part and three IV-part fractures resulted in each group. The preloading of the rotator cuff muscles had no further influence on the fracture configuration. High-speed videos of the fracture simulation revealed identical fracture mechanisms for both groups. We observed a two-step fracture mechanism, with initial impaction of the head segment against the glenoid followed by fracturing of the head and the tuberosities and then with further impaction of the shaft against the acromion, which lead to separation of the tuberosities. Conclusion A high energetic axial impulse can reliably induce realistic proximal humerus fractures in cadaveric specimens. The preload of the rotator cuff muscles had no influence on initial fracture configuration. Therefore, fracture simulation in the proximal humerus is less elaborate. Using the presented technique, pre-fractured specimens are available for real-life surgical education. KW - Proximal humerus fracture KW - Biomechanical simulation KW - Fracture configuration KW - Fracture simulation KW - Rotator cuff Y1 - 2022 U6 - https://doi.org/10.1007/s00402-022-04471-9 SN - 1434-3916 PB - Springer CY - Berlin, Heidelberg ER - TY - JOUR A1 - Chloé, Radermacher A1 - Malyaran, Hanna A1 - Craveiro, Rogerio Bastos A1 - Peglow, Sarah A1 - Behbahani, Mehdi A1 - Pufe, Thomas A1 - Wolf, Michael A1 - Neuss, Sabine T1 - Mechanical loading on cementoblasts: a mini review JF - Osteologie N2 - Orthodontic treatments are concomitant with mechanical forces and thereby cause teeth movements. The applied forces are transmitted to the tooth root and the periodontal ligaments which is compressed on one side and tensed up on the other side. Indeed, strong forces can lead to tooth root resorption and the crown-to-tooth ratio is reduced with the potential for significant clinical impact. The cementum, which covers the tooth root, is a thin mineralized tissue of the periodontium that connects the periodontal ligament with the tooth and is build up by cementoblasts. The impact of tension and compression on these cells is investigated in several in vivo and in vitro studies demonstrating differences in protein expression and signaling pathways. In summary, osteogenic marker changes indicate that cyclic tensile forces support whereas static tension inhibits cementogenesis. Furthermore, cementogenesis experiences the same protein expression changes in static conditions as static tension, but cyclic compression leads to the exact opposite of cyclic tension. Consistent with marker expression changes, the singaling pathways of Wnt/ß-catenin and RANKL/OPG show that tissue compression leads to cementum degradation and tension forces to cementogenesis. However, the cementum, and in particular its cementoblasts, remain a research area which should be explored in more detail to understand the underlying mechanism of bone resorption and remodeling after orthodontic treatments. KW - Cementoblast KW - Compression KW - Tension KW - Mechanotransduction KW - Forces Y1 - 2022 U6 - https://doi.org/10.1055/a-1826-0777 SN - 1019-1291 VL - 31 IS - 2 SP - 111 EP - 118 PB - Thieme CY - Stuttgart ER - TY - THES A1 - Gaigall, Daniel T1 - Vergleich von statistischen Tests im verbundenen und unabhängigen Stichprobenfall N2 - Es werden Effizienzbegriffe zum Vergleich von statistischen Tests basierend auf verschiedenen statistischen Experimenten eingeführt. Dabei handelt es sich um die schon aus dem Vergleich von statistischen Tests in je demselben Modell bekannten asymptotischen relativen Effizienzen wie die Hodges-Lehmann-Effizienz, die Bahadur-Effizienz und die Pitman-Effizienz sowie um Kriterien basierend auf Volumina von Konfidenzbereichen. Effizienzaussagen werden unter anderem für Likelihood-Quotienten-Tests und Waldsche Tests im Rahmen eines allgemeinen multivariaten parametrischen Modells erhalten. Statistische Tests zur Prüfung von Hypothesen über die relative Wirksamkeit zweier Experimente werden vorgeschlagen. Auf der Grundlage der erhaltenen Ergebnisse erfolgt ein Vergleich der Wirksamkeit von korrespondierenden Verfahren bei verbundener Stichprobenerhebung und unabhängiger Stichprobenerhebung. Die Rolle der Kovarianzmatrix bei verbundener Stichprobenerhebung wird insbesondere unter der Annahme, dass die zugrunde liegenden Verteilungen durch k-parametrische Exponentialfamilien modellierbar sind, herausgearbeitet. Verbindungen zu Effizienzbegriffen bei Punkt- und Konfidenzbereichsschätzverfahren werden aufgezeigt. Ausführlichere Untersuchungen betreffen die korrespondierenden Hotellingschen T²-Tests im multivariaten Normalverteilungsfall, die klassischen Homogenitatstests bei k × k-Kontingenztafeln und die Wilcoxon Tests in nichtparametrischen Lagealternativmodellen KW - Vergleich von Experimenten KW - Hypothesentests KW - Effizienz KW - testing hypotheses KW - efficiency Y1 - 2016 U6 - https://doi.org/10.15488/8678 N1 - Dissertation, Gottfried Wilhelm Leibniz Universität Hannover, 2016 PB - Gottfried Wilhelm Leibniz Universität Hannover CY - Hannover ER - TY - CHAP A1 - Engelmann, Ulrich M. A1 - Baumann, Martin ED - Herbig, Nicola ED - Poppelreuter, Stefan T1 - Moderationsexpertise für QMBs – Onlinemoderation T2 - Qualitätsmanagement im Gesundheitswesen N2 - Damit Sie auch in den immer häufiger werdenden Onlineveranstaltungen als Moderator gut bestehen, sollten Sie wissen, was bei der Onlinemoderation im Besonderen zu beachten ist. In diesem dritten Teil der Beitragsserie erfahren Sie, warum online anders als offline ist. Die technischen Möglichkeiten werden vorgestellt und auch wie diese zu nutzen sind. Schließlich erhalten Sie Tipps, die Sie beim Sprechen online beachten sollten. Y1 - 2023 SN - 978-3-8249-0714-4 SP - Kapitel 10816 PB - TÜV-Verlag CY - Köln ER - TY - CHAP A1 - Engelmann, Ulrich M. ED - Lindinger, Markus ED - Bartsch, Oliver T1 - Moderationsexpertise – Onlinemoderation T2 - IT-Servicemanagement N2 - Damit Sie auch in den immer häufiger werdenden Onlineveranstaltungen als Moderator gut bestehen, sollten Sie wissen, was bei der Onlinemoderation im Besonderen zu beachten ist. In diesem dritten Teil der Beitragsserie erfahren Sie, warum online anders als offline ist. Die technischen Möglichkeiten werden vorgestellt und auch wie diese zu nutzen sind. Schließlich erhalten Sie Tipps, die Sie beim Sprechen online beachten sollten. Y1 - 2023 SN - 978-3-8249-1154-7 SP - Kapitel 05532 PB - TÜV-Verlag CY - Köln ER - TY - JOUR A1 - Herssens, Nolan A1 - Cowburn, James A1 - Albracht, Kirsten A1 - Braunstein, Bjoern A1 - Cazzola, Dario A1 - Colyer, Steffi A1 - Minetti, Alberto E. A1 - Pavei, Gaspare A1 - Rittweger, Jörn A1 - Weber, Tobias A1 - Green, David A. ED - Cattaneo, Luigi T1 - Movement in low gravity environments (MoLo) programme – the MoLo-L.O.O.P. study protocol JF - PLOS ONE / Public Library of Science N2 - Exposure to prolonged periods in microgravity is associated with deconditioning of the musculoskeletal system due to chronic changes in mechanical stimulation. Given astronauts will operate on the Lunar surface for extended periods of time, it is critical to quantify both external (e.g., ground reaction forces) and internal (e.g., joint reaction forces) loads of relevant movements performed during Lunar missions. Such knowledge is key to predict musculoskeletal deconditioning and determine appropriate exercise countermeasures associated with extended exposure to hypogravity. Y1 - 2022 U6 - https://doi.org/10.1371/journal.pone.0278051 SN - 1932-6203 VL - 17 IS - 11 PB - Plos CY - San Francisco ER - TY - JOUR A1 - Morais, Paulo V. A1 - Suman, Pedro H. A1 - Schöning, Michael Josef A1 - Siqueira Junior, José R. A1 - Orlandi, Marcelo O. T1 - Layer-by-layer film based on Sn₃O₄ nanobelts as sensing units to detect heavy metals using a capacitive field-effect sensor platform JF - Chemosensors N2 - Lead and nickel, as heavy metals, are still used in industrial processes, and are classified as “environmental health hazards” due to their toxicity and polluting potential. The detection of heavy metals can prevent environmental pollution at toxic levels that are critical to human health. In this sense, the electrolyte–insulator–semiconductor (EIS) field-effect sensor is an attractive sensing platform concerning the fabrication of reusable and robust sensors to detect such substances. This study is aimed to fabricate a sensing unit on an EIS device based on Sn₃O₄ nanobelts embedded in a polyelectrolyte matrix of polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) using the layer-by-layer (LbL) technique. The EIS-Sn₃O₄ sensor exhibited enhanced electrochemical performance for detecting Pb²⁺ and Ni²⁺ ions, revealing a higher affinity for Pb²⁺ ions, with sensitivities of ca. 25.8 mV/decade and 2.4 mV/decade, respectively. Such results indicate that Sn₃O₄ nanobelts can contemplate a feasible proof-of-concept capacitive field-effect sensor for heavy metal detection, envisaging other future studies focusing on environmental monitoring. KW - Sn₃O₄ KW - nanobelts KW - field-effect sensor KW - LbL films KW - heavy metals Y1 - 2023 U6 - https://doi.org/10.3390/chemosensors11080436 SN - 2227-9040 N1 - This article belongs to the Special Issue The Application of Electrochemical Sensors or Biosensors Based on Nanomaterials VL - 11 IS - 8 PB - MDPI CY - Basel ER - TY - THES A1 - Gaigall, Daniel T1 - On selected problems in multivariate analysis N2 - Selected problems in the field of multivariate statistical analysis are treated. Thereby, one focus is on the paired sample case. Among other things, statistical testing problems of marginal homogeneity are under consideration. In detail, properties of Hotelling‘s T² test in a special parametric situation are obtained. Moreover, the nonparametric problem of marginal homogeneity is discussed on the basis of possibly incomplete data. In the bivariate data case, properties of the Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic on the basis of partly not identically distributed data are investigated. Similar testing problems are treated within the scope of the application of a result for the empirical process of the concomitants for partly categorial data. Furthermore, testing changes in the modeled solvency capital requirement of an insurance company by means of a paired sample from an internal risk model is discussed. Beyond the paired sample case, a new asymptotic relative efficiency concept based on the expected volumes of multidimensional confidence regions is introduced. Besides, a new approach for the treatment of the multi-sample goodness-of-fit problem is presented. Finally, a consistent test for the treatment of the goodness-of-fit problem is developed for the background of huge or infinite dimensional data. KW - Paired sample KW - Marginal homogeneity KW - Incomplete data KW - Asymptotic relative efficiency KW - Volumes of confidence regions Y1 - 2023 U6 - https://doi.org/10.15488/14304 N1 - Gottfried Wilhelm Leibniz Universität Hannover ER - TY - CHAP A1 - Büsgen, André A1 - Klöser, Lars A1 - Kohl, Philipp A1 - Schmidts, Oliver A1 - Kraft, Bodo A1 - Zündorf, Albert ED - Cuzzocrea, Alfredo ED - Gusikhin, Oleg ED - Hammoudi, Slimane ED - Quix, Christoph T1 - From cracked accounts to fake IDs: user profiling on German telegram black market channels T2 - Data Management Technologies and Applications N2 - Messenger apps like WhatsApp and Telegram are frequently used for everyday communication, but they can also be utilized as a platform for illegal activity. Telegram allows public groups with up to 200.000 participants. Criminals use these public groups for trading illegal commodities and services, which becomes a concern for law enforcement agencies, who manually monitor suspicious activity in these chat rooms. This research demonstrates how natural language processing (NLP) can assist in analyzing these chat rooms, providing an explorative overview of the domain and facilitating purposeful analyses of user behavior. We provide a publicly available corpus of annotated text messages with entities and relations from four self-proclaimed black market chat rooms. Our pipeline approach aggregates the extracted product attributes from user messages to profiles and uses these with their sold products as features for clustering. The extracted structured information is the foundation for further data exploration, such as identifying the top vendors or fine-granular price analyses. Our evaluation shows that pretrained word vectors perform better for unsupervised clustering than state-of-the-art transformer models, while the latter is still superior for sequence labeling. KW - Clustering KW - Natural language processing KW - Information extraction KW - Profile extraction KW - Text mining Y1 - 2023 SN - 978-3-031-37889-8 (Print) SN - 978-3-031-37890-4 (Online) U6 - https://doi.org/10.1007/978-3-031-37890-4_9 N1 - 10th International Conference, DATA 2021, Virtual Event, July 6–8, 2021, and 11th International Conference, DATA 2022, Lisbon, Portugal, July 11-13, 2022 SP - 176 EP - 202 PB - Springer CY - Cham ER - TY - CHAP A1 - Kohl, Philipp A1 - Freyer, Nils A1 - Krämer, Yoka A1 - Werth, Henri A1 - Wolf, Steffen A1 - Kraft, Bodo A1 - Meinecke, Matthias A1 - Zündorf, Albert ED - Conte, Donatello ED - Fred, Ana ED - Gusikhin, Oleg ED - Sansone, Carlo T1 - ALE: a simulation-based active learning evaluation framework for the parameter-driven comparison of query strategies for NLP T2 - Deep Learning Theory and Applications N2 - Supervised machine learning and deep learning require a large amount of labeled data, which data scientists obtain in a manual, and time-consuming annotation process. To mitigate this challenge, Active Learning (AL) proposes promising data points to annotators they annotate next instead of a subsequent or random sample. This method is supposed to save annotation effort while maintaining model performance. However, practitioners face many AL strategies for different tasks and need an empirical basis to choose between them. Surveys categorize AL strategies into taxonomies without performance indications. Presentations of novel AL strategies compare the performance to a small subset of strategies. Our contribution addresses the empirical basis by introducing a reproducible active learning evaluation (ALE) framework for the comparative evaluation of AL strategies in NLP. The framework allows the implementation of AL strategies with low effort and a fair data-driven comparison through defining and tracking experiment parameters (e.g., initial dataset size, number of data points per query step, and the budget). ALE helps practitioners to make more informed decisions, and researchers can focus on developing new, effective AL strategies and deriving best practices for specific use cases. With best practices, practitioners can lower their annotation costs. We present a case study to illustrate how to use the framework. KW - Active learning KW - Query learning KW - Natural language processing KW - Deep learning KW - Reproducible research Y1 - 2023 SN - 978-3-031-39058-6 (Print) SN - 978-3-031-39059-3 (Online) U6 - https://doi.org/10.1007/978-3-031-39059-3_16 N1 - 4th International Conference, DeLTA 2023, Rome, Italy, July 13–14, 2023. SP - 235 EP - 253 PB - Springer CY - Cham ER - TY - JOUR A1 - Waldvogel, Janice A1 - Freyler, Kathrin A1 - Helm, Michael A1 - Monti, Elena A1 - Stäudle, Benjamin A1 - Gollhofer, Albert A1 - Narici, Marco V. A1 - Ritzmann, Ramona A1 - Albracht, Kirsten T1 - Changes in gravity affect neuromuscular control, biomechanics, and muscle-tendon mechanics in energy storage and dissipation tasks JF - Journal of Applied Physiology N2 - This study evaluates neuromechanical control and muscle-tendon interaction during energy storage and dissipation tasks in hypergravity. During parabolic flights, while 17 subjects performed drop jumps (DJs) and drop landings (DLs), electromyography (EMG) of the lower limb muscles was combined with in vivo fascicle dynamics of the gastrocnemius medialis, two-dimensional (2D) kinematics, and kinetics to measure and analyze changes in energy management. Comparisons were made between movement modalities executed in hypergravity (1.8 G) and gravity on ground (1 G). In 1.8 G, ankle dorsiflexion, knee joint flexion, and vertical center of mass (COM) displacement are lower in DJs than in DLs; within each movement modality, joint flexion amplitudes and COM displacement demonstrate higher values in 1.8 G than in 1 G. Concomitantly, negative peak ankle joint power, vertical ground reaction forces, and leg stiffness are similar between both movement modalities (1.8 G). In DJs, EMG activity in 1.8 G is lower during the COM deceleration phase than in 1 G, thus impairing quasi-isometric fascicle behavior. In DLs, EMG activity before and during the COM deceleration phase is higher, and fascicles are stretched less in 1.8 G than in 1 G. Compared with the situation in 1 G, highly task-specific neuromuscular activity is diminished in 1.8 G, resulting in fascicle lengthening in both movement modalities. Specifically, in DJs, a high magnitude of neuromuscular activity is impaired, resulting in altered energy storage. In contrast, in DLs, linear stiffening of the system due to higher neuromuscular activity combined with lower fascicle stretch enhances the buffering function of the tendon, and thus the capacity to safely dissipate energy. KW - electromyography KW - locomotion KW - overload KW - stretch-shortening cycle KW - ultrasound Y1 - 2023 U6 - https://doi.org/10.1152/japplphysiol.00279.2022 SN - 1522-1601 (Onlineausgabe) SN - 8750-7587 (Druckausgabe) VL - 134 IS - 1 SP - 190 EP - 202 PB - American Physiological Society CY - Bethesda, Md. ER - TY - JOUR A1 - Heieis, Jule A1 - Böcker, Jonas A1 - D'Angelo, Olfa A1 - Mittag, Uwe A1 - Albracht, Kirsten A1 - Schönau, Eckhard A1 - Meyer, Andreas A1 - Voigtmann, Thomas A1 - Rittweger, Jörn T1 - Curvature of gastrocnemius muscle fascicles as function of muscle–tendon complex length and contraction in humans JF - Physiological Reports N2 - It has been shown that muscle fascicle curvature increases with increasing contraction level and decreasing muscle–tendon complex length. The analyses were done with limited examination windows concerning contraction level, muscle–tendon complex length, and/or intramuscular position of ultrasound imaging. With this study we aimed to investigate the correlation between fascicle arching and contraction, muscle–tendon complex length and their associated architectural parameters in gastrocnemius muscles to develop hypotheses concerning the fundamental mechanism of fascicle curving. Twelve participants were tested in five different positions (90°/105°*, 90°/90°*, 135°/90°*, 170°/90°*, and 170°/75°*; *knee/ankle angle). They performed isometric contractions at four different contraction levels (5%, 25%, 50%, and 75% of maximum voluntary contraction) in each position. Panoramic ultrasound images of gastrocnemius muscles were collected at rest and during constant contraction. Aponeuroses and fascicles were tracked in all ultrasound images and the parameters fascicle curvature, muscle–tendon complex strain, contraction level, pennation angle, fascicle length, fascicle strain, intramuscular position, sex and age group were analyzed by linear mixed effect models. Mean fascicle curvature of the medial gastrocnemius increased with contraction level (+5 m−1 from 0% to 100%; p = 0.006). Muscle–tendon complex length had no significant impact on mean fascicle curvature. Mean pennation angle (2.2 m−1 per 10°; p < 0.001), inverse mean fascicle length (20 m−1 per cm−1; p = 0.003), and mean fascicle strain (−0.07 m−1 per +10%; p = 0.004) correlated with mean fascicle curvature. Evidence has also been found for intermuscular, intramuscular, and sex-specific intramuscular differences of fascicle curving. Pennation angle and the inverse fascicle length show the highest predictive capacities for fascicle curving. Due to the strong correlations between pennation angle and fascicle curvature and the intramuscular pattern of curving we suggest for future studies to examine correlations between fascicle curvature and intramuscular fluid pressure. KW - biomechanics KW - connective tissue KW - physiology KW - ultrasound Y1 - 2023 U6 - https://doi.org/10.14814/phy2.15739 SN - 2051-817X VL - 11 IS - 11 SP - e15739, Seite 1-11 PB - Wiley ER - TY - CHAP A1 - Klöser, Lars A1 - Büsgen, André A1 - Kohl, Philipp A1 - Kraft, Bodo A1 - Zündorf, Albert ED - Conte, Donatello ED - Fred, Ana ED - Gusikhin, Oleg ED - Sansone, Carlo T1 - Explaining relation classification models with semantic extents T2 - Deep Learning Theory and Applications N2 - In recent years, the development of large pretrained language models, such as BERT and GPT, significantly improved information extraction systems on various tasks, including relation classification. State-of-the-art systems are highly accurate on scientific benchmarks. A lack of explainability is currently a complicating factor in many real-world applications. Comprehensible systems are necessary to prevent biased, counterintuitive, or harmful decisions. We introduce semantic extents, a concept to analyze decision patterns for the relation classification task. Semantic extents are the most influential parts of texts concerning classification decisions. Our definition allows similar procedures to determine semantic extents for humans and models. We provide an annotation tool and a software framework to determine semantic extents for humans and models conveniently and reproducibly. Comparing both reveals that models tend to learn shortcut patterns from data. These patterns are hard to detect with current interpretability methods, such as input reductions. Our approach can help detect and eliminate spurious decision patterns during model development. Semantic extents can increase the reliability and security of natural language processing systems. Semantic extents are an essential step in enabling applications in critical areas like healthcare or finance. Moreover, our work opens new research directions for developing methods to explain deep learning models. KW - Relation classification KW - Natural language processing KW - Natural language understanding KW - Information extraction KW - Trustworthy artificial intelligence Y1 - 2023 SN - 978-3-031-39058-6 (Print) SN - 978-3-031-39059-3 (Online) U6 - https://doi.org/10.1007/978-3-031-39059-3_13 N1 - 4th International Conference, DeLTA 2023, Rome, Italy, July 13–14, 2023. SP - 189 EP - 208 PB - Springer CY - Cham ER - TY - RPRT A1 - Göll, Fabian A1 - Braunstein, Björn A1 - Albracht, Kirsten T1 - Lernende roboterassistierte Systeme für das neuromuskuläre Training - RoSylerNT; Teilvorhaben: Entwicklung eines neuromuskuloskelettalen Modells als Basis für die Interaktionsfähigkeiten autonomer Assistenzsysteme KW - Robotik KW - Rehabilitationsmedizin KW - Neuromuskuläres System KW - Rehabilitatives Training KW - Trainingsgerät Y1 - 2021 U6 - https://doi.org/10.2314/KXP:1855318741 N1 - Förderkennzeichen BMBF 16SV7853 Schlussbericht der Deutschen Sporthochschule Köln für das Vorhaben RoSylerNT Laufzeit: 01.08.2017-31.07.2021 PB - Deutsche Sporthochschule Köln CY - Köln ER - TY - JOUR A1 - Özsoylu, Dua A1 - Aliazizi, Fereshteh A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Template bacteria-free fabrication of surface imprinted polymer-based biosensor for E. coli detection using photolithographic mimics: Hacking bacterial adhesion JF - Biosensors and Bioelectronics N2 - As one class of molecular imprinted polymers (MIPs), surface imprinted polymer (SIP)-based biosensors show great potential in direct whole-bacteria detection. Micro-contact imprinting, that involves stamping the template bacteria immobilized on a substrate into a pre-polymerized polymer matrix, is the most straightforward and prominent method to obtain SIP-based biosensors. However, the major drawbacks of the method arise from the requirement for fresh template bacteria and often non-reproducible bacteria distribution on the stamp substrate. Herein, we developed a positive master stamp containing photolithographic mimics of the template bacteria (E. coli) enabling reproducible fabrication of biomimetic SIP-based biosensors without the need for the “real” bacteria cells. By using atomic force and scanning electron microscopy imaging techniques, respectively, the E. coli-capturing ability of the SIP samples was tested, and compared with non-imprinted polymer (NIP)-based samples and control SIP samples, in which the cavity geometry does not match with E. coli cells. It was revealed that the presence of the biomimetic E. coli imprints with a specifically designed geometry increases the sensor E. coli-capturing ability by an “imprinting factor” of about 3. These findings show the importance of geometry-guided physical recognition in bacterial detection using SIP-based biosensors. In addition, this imprinting strategy was employed to interdigitated electrodes and QCM (quartz crystal microbalance) chips. E. coli detection performance of the sensors was demonstrated with electrochemical impedance spectroscopy (EIS) and QCM measurements with dissipation monitoring technique (QCM-D). KW - Surface imprinted polymer KW - E. coli detection KW - Photolithographic mimics KW - Master stamp KW - Quartz crystal microbalance Y1 - 2024 U6 - https://doi.org/10.1016/j.bios.2024.116491 SN - 1873-4235 (eISSN) SN - 0956-5663 N1 - Corresponding author: Michael J. Schöning VL - 261 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ketelhut, Maike A1 - Brügge, G. M. A1 - Göll, Fabian A1 - Braunstein, Bjoern A1 - Albracht, Kirsten A1 - Abel, Dirk T1 - Adaptive iterative learning control of an industrial robot during neuromuscular training JF - IFAC PapersOnLine N2 - To prevent the reduction of muscle mass and loss of strength coming along with the human aging process, regular training with e.g. a leg press is suitable. However, the risk of training-induced injuries requires the continuous monitoring and controlling of the forces applied to the musculoskeletal system as well as the velocity along the motion trajectory and the range of motion. In this paper, an adaptive norm-optimal iterative learning control algorithm to minimize the knee joint loadings during the leg extension training with an industrial robot is proposed. The response of the algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee and compared to the results of a higher-order iterative learning control algorithm, a robust iterative learning control and a recently proposed conventional norm-optimal iterative learning control algorithm. Although significant improvements in performance are made compared to the conventional norm-optimal iterative learning control algorithm with a small learning factor, for the developed approach as well as the robust iterative learning control algorithm small steady state errors occur. KW - Iterative learning control KW - Robotic rehabilitation KW - Adaptive control Y1 - 2020 U6 - https://doi.org/10.1016/j.ifacol.2020.12.741 SN - 2405-8963 VL - 53 IS - 2 SP - 16468 EP - 16475 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ketelhut, Maike A1 - Kolditz, Melanie A1 - Göll, Fabian A1 - Braunstein, Bjoern A1 - Albracht, Kirsten A1 - Abel, Dirk T1 - Admittance control of an industrial robot during resistance training JF - IFAC-PapersOnLine N2 - Neuromuscular strength training of the leg extensor muscles plays an important role in the rehabilitation and prevention of age and wealth related diseases. In this paper, we focus on the design and implementation of a Cartesian admittance control scheme for isotonic training, i.e. leg extension and flexion against a predefined weight. For preliminary testing and validation of the designed algorithm an experimental research and development platform consisting of an industrial robot and a force plate mounted at its end-effector has been used. Linear, diagonal and arbitrary two-dimensional motion trajectories with different weights for the leg extension and flexion part are applied. The proposed algorithm is easily adaptable to trajectories consisting of arbitrary six-dimensional poses and allows the implementation of individualized trajectories. KW - Assistive technology KW - Rehabilitation engineering KW - Human-Computer interaction KW - Automatic control Y1 - 2019 U6 - https://doi.org/10.1016/j.ifacol.2019.12.102 SN - 2405-8963 N1 - 14th IFAC Symposium on Analysis, Design, and Evaluation of Human Machine Systems HMS 2019 Tallinn, Estonia, 16–91 September 2019 VL - 52 IS - 19 SP - 223 EP - 228 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Ketelhut, Maike A1 - Göll, Fabian A1 - Braunstein, Bjoern A1 - Albracht, Kirsten A1 - Abel, Dirk T1 - Iterative learning control of an industrial robot for neuromuscular training T2 - 2019 IEEE Conference on Control Technology and Applications N2 - Effective training requires high muscle forces potentially leading to training-induced injuries. Thus, continuous monitoring and controlling of the loadings applied to the musculoskeletal system along the motion trajectory is required. In this paper, a norm-optimal iterative learning control algorithm for the robot-assisted training is developed. The algorithm aims at minimizing the external knee joint moment, which is commonly used to quantify the loading of the medial compartment. To estimate the external knee joint moment, a musculoskeletal lower extremity model is implemented in OpenSim and coupled with a model of an industrial robot and a force plate mounted at its end-effector. The algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee. The results show that the algorithm is able to minimize the external knee joint moment in all three cases and converges after less than seven iterations. KW - Knee KW - Training KW - Load modeling KW - Force KW - Iterative learning control Y1 - 2019 SN - 978-1-7281-2767-5 (ePub) SN - 978-1-7281-2766-8 (USB) SN - 978-1-7281-2768-2 (PoD) U6 - https://doi.org/10.1109/CCTA.2019.8920659 N1 - 2019 IEEE Conference on Control Technology and Applications (CCTA) Hong Kong, China, August 19-21, 2019 PB - IEEE CY - New York ER - TY - GEN A1 - Blottner, Dieter A1 - Hastermann, Maria A1 - Muckelt, Paul A1 - Albracht, Kirsten A1 - Schoenrock, Britt A1 - Salanova, Michele A1 - Warner, Martin A1 - Gunga, Hans-Christian A1 - Stokes, Maria T1 - MYOTONES - Inflight muscle health status monitoring during long-duration space missions onboard the International Space Station: a single case study T2 - IAC Papers Archive N2 - The MYOTONES experiment is the first to monitor changes in the basic biomechanical properties (tone, elasticity and stiffness) of the resting human myofascial system due to microgravity with a oninvasive, portable device on board the ISS. The MyotonPRO device applies several brief mechanical stimuli to the surface of the skin, and the natural oscillation signals of the tissue beneath are detected and computed by the MyotonPRO. Thus, an objective, quick and easy determination of the state of the underlying tissue is possible. Two preflight, four inflight and four post flight measurements were performed on a male astronaut using the same 10 measurement points (MP) for each session. MPs were located on the plantar fascia, Achilles tendon, M. soleus, M. gastrocnemius, M. multifidus, M. splenius capitis, M. deltoideus anterior, M. rectus femoris, infrapatellar tendon, M. tibialis anterior. Subcutaneous tissues thickness above the MPs was measured using ultrasound imaging. Magnetic resonance images (MRI) of lower limb muscles and functional tests were also performed pre- and postflight. Our first measurements on board the ISS confirmed increased tone and stiffness of the lumbar multifidus muscle, an important trunk stabilizer, dysfunction of which is known to be associated with back pain. Furthermore, reduced tone and stiffness of Achilles tendon and plantar fascia were observed inflight vs. preflight, confirming previous findings from terrestrial analog studies and parabolic flights. Unexpectedly, the deltoid showed negative inflight changes in tone and stiffness, and increased elasticity, suggesting a potential risk of muscle atrophy in longer spaceflight that should be addressed by adequate inflight countermeasure protocols. Most values from limb and back MPS showed deflected patterns (in either directions) from inflight shortly after the re-entry phase on the landing day and one week later. Most parameter values then normalized to baseline after 3 weeks likely due to 1G re-adaptation and possible outcome of the reconditioning protocol. No major changes in subcutaneous tissues thickness above the MPs were found inflight vs preflight, suggesting no bias (i.e., fluid shift, extreme tissue thickening or loss). Pre- and postflight MRI and functional tests showed negligible changes in calf muscle size, power and force, which is likely due to training effects from current inflight exercise protocols. The MYOTONES experiment is currently ongoing to collect data from further crew members. The potential impact of this research is to better understand the effects of microgravity and countermeasures over the time course of an ISS mission cycle. This will enable exercise countermeasures to be tailored Y1 - 2019 SN - 00741795 N1 - International Astronautical Congress: space: the power of the past, the promise of the future - Washington DC, USA/Vereinigte Staaten von Amerika Dauer: 21.10.2019 → 25.10.2019 PB - Pergamon CY - Oxford ER - TY - JOUR A1 - Werkhausen, Amelie A1 - Cronin, Neil J. A1 - Albracht, Kirsten A1 - Paulsen, Gøran A1 - Larsen, Askild V. A1 - Bojsen-Møller, Jens A1 - Seynnes, Olivier R. T1 - Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running JF - PeerJ N2 - Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric singleleg plantarflexion contractions three times per week for ten weeks, and another ten subjects formed a control group. Before and after the training period, Achilles tendon stiffness was estimated, and muscle-tendon mechanics were assessed during running at preferred speed using ultrasonography, kinematics and kinetics. Results Achilles tendon stiffness increased by 18% (P <0:01) in the training group, but the associated reduction in strain seen during isometric contractions was not statistically significant. Tendon elongation during the stance phase of running was similar after training, but tendon recoil was reduced by 30% (P <0:01), while estimated tendon force remained unchanged. Neither gastrocnemius medialis nor soleus fascicle shortening during stance was affected by training. Discussion These results show that a training-induced increase in Achilles tendon stiffness altered tendon behaviour during running. Despite training-induced changes in tendon mechanical properties and recoil behaviour, the data suggest that fascicle shortening patterns were preserved for the running speed that we examined. The asymmetrical changes in tendon strain patterns supports the notion that simple inseries models do not fully explain the mechanical output of the muscle-tendon unit during a complex task like running. KW - Achilles tendon KW - Stiffness KW - Running KW - Tendon properties KW - Architectural gear ratio Y1 - 2019 U6 - https://doi.org/10.7717/peerj.6764 SN - 21678359 PB - Peer CY - London ER - TY - JOUR A1 - Ketelhut, Maike A1 - Göll, Fabian A1 - Braunstein, Björn A1 - Albracht, Kirsten A1 - Abel, Dirk T1 - Comparison of different training algorithms for the leg extension training with an industrial robot JF - Current Directions in Biomedical Engineering N2 - In the past, different training scenarios have been developed and implemented on robotic research platforms, but no systematic analysis and comparison have been done so far. This paper deals with the comparison of an isokinematic (motion with constant velocity) and an isotonic (motion against constant weight) training algorithm. Both algorithms are designed for a robotic research platform consisting of a 3D force plate and a high payload industrial robot, which allows leg extension training with arbitrary six-dimensional motion trajectories. In the isokinematic as well as the isotonic training algorithm, individual paths are defined i n C artesian s pace by sufficient s upport p oses. I n t he i sotonic t raining s cenario, the trajectory is adapted to the measured force as the robot should only move along the trajectory as long as the force applied by the user exceeds a minimum threshold. In the isotonic training scenario however, the robot’s acceleration is a function of the force applied by the user. To validate these findings, a simulative experiment with a simple linear trajectory is performed. For this purpose, the same force path is applied in both training scenarios. The results illustrate that the algorithms differ in the force dependent trajectory adaption. KW - Rehabilitation Technology and Prosthetics KW - Surgical Navigation and Robotics Y1 - 2018 U6 - https://doi.org/10.1515/cdbme-2018-0005 SN - 2364-5504 VL - 4 IS - 1 SP - 17 EP - 20 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Stäudle, Benjamin A1 - Seynnes, Olivier A1 - Laps, Guido A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Altered gastrocnemius contractile behavior in former achilles tendon rupture patients during walking JF - Frontiers in Physiology N2 - Achilles tendon rupture (ATR) remains associated with functional limitations years after injury. Architectural remodeling of the gastrocnemius medialis (GM) muscle is typically observed in the affected leg and may compensate force deficits caused by a longer tendon. Yet patients seem to retain functional limitations during—low-force—walking gait. To explore the potential limits imposed by the remodeled GM muscle-tendon unit (MTU) on walking gait, we examined the contractile behavior of muscle fascicles during the stance phase. In a cross-sectional design, we studied nine former patients (males; age: 45 ± 9 years; height: 180 ± 7 cm; weight: 83 ± 6 kg) with a history of complete unilateral ATR, approximately 4 years post-surgery. Using ultrasonography, GM tendon morphology, muscle architecture at rest, and fascicular behavior were assessed during walking at 1.5 m⋅s–1 on a treadmill. Walking patterns were recorded with a motion capture system. The unaffected leg served as control. Lower limbs kinematics were largely similar between legs during walking. Typical features of ATR-related MTU remodeling were observed during the stance sub-phases corresponding to series elastic element (SEE) lengthening (energy storage) and SEE shortening (energy release), with shorter GM fascicles (36 and 36%, respectively) and greater pennation angles (8° and 12°, respectively). However, relative to the optimal fascicle length for force production, fascicles operated at comparable length in both legs. Similarly, when expressed relative to optimal fascicle length, fascicle contraction velocity was not different between sides, except at the time-point of peak series elastic element (SEE) length, where it was 39 ± 49% lower in the affected leg. Concomitantly, fascicles rotation during contraction was greater in the affected leg during the whole stance-phase, and architectural gear ratios (AGR) was larger during SEE lengthening. Under the present testing conditions, former ATR patients had recovered a relatively symmetrical walking gait pattern. Differences in seen AGR seem to accommodate the profound changes in MTU architecture, limiting the required fascicle shortening velocity. Overall, the contractile behavior of the GM fascicles does not restrict length- or velocity-dependent force potentials during this locomotor task. KW - tendon rupture KW - muscle fascicle behavior KW - walking gait KW - force generation KW - ultrasound imaging Y1 - 2022 U6 - https://doi.org/10.3389/fphys.2022.792576 SN - 1664-042X VL - 13 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Quittmann, Oliver J. A1 - Abel, Thomas A1 - Albracht, Kirsten A1 - Strüder, Heiko K. T1 - Biomechanics of all-out handcycling exercise: kinetics, kinematics and muscular activity of a 15-s sprint test in able-bodied participants JF - Sports Biomechanics N2 - This study aims to quantify the kinematics, kinetics and muscular activity of all-out handcycling exercise and examine their alterations during the course of a 15-s sprint test. Twelve able-bodied competitive triathletes performed a 15-s all-out sprint test in a recumbent racing handcycle that was attached to an ergometer. During the sprint test, tangential crank kinetics, 3D joint kinematics and muscular activity of 10 muscles of the upper extremity and trunk were examined using a power metre, motion capturing and surface electromyography (sEMG), respectively. Parameters were compared between revolution one (R1), revolution two (R2), the average of revolution 3 to 13 (R3) and the average of the remaining revolutions (R4). Shoulder abduction and internal-rotation increased, whereas maximal shoulder retroversion decreased during the sprint. Except for the wrist angles, angular velocity increased for every joint of the upper extremity. Several muscles demonstrated an increase in muscular activation, an earlier onset of muscular activation in crank cycle and an increased range of activation. During the course of a 15-s all-out sprint test in handcycling, the shoulder muscles and the muscles associated to the push phase demonstrate indications for short-duration fatigue. These findings are helpful to prevent injuries and improve performance in all-out handcycling. KW - Handbike KW - sEMG KW - Paralympic sport KW - performance testing KW - high-intensity exercise Y1 - 2022 U6 - https://doi.org/10.1080/14763141.2020.1745266 SN - 1752-6116 (Onlineausgabe) SN - 1476-3141 (Druckausgabe) VL - 21 IS - 10 SP - 1200 EP - 1223 PB - Taylor & Francis CY - London ER -