TY - JOUR A1 - Auer, Simon A1 - Schiebl, Jonas A1 - Iversen, Kristoffer A1 - Subhash Chander, Divyaksh A1 - Damsgaard, Michael A1 - Dendorfer, Sebastian T1 - Biomechanical assessment of the design and efficiency of occupational exoskeletons with the AnyBody Modeling System JF - Zeitschrift für Arbeitswissenschaften N2 - Exoskeletons were invented over 100 years ago but have only become popular in the last two decades, especially in the working industry as they can decrease work-related loads significantly. The most often used exoskeletons are for the lower back and shoulder since these are commonly affected body regions. All devices have in common that their purpose is to reduce internal loads of vulnerable body regions. Nevertheless, there is still little understanding on how biomechanical loading in the human body changes when exoskeletons are used. Therefore, further analyses are needed. A promising candidate for these are musculoskeletal models, which are based on an inverse dynamics approach and can calculate external parameters such as ground reaction forces or other interaction forces as well as internal parameters such as joint reaction forces or muscle activities. The various examples in the literature show that these models are increasingly used for assessing the biomechanical effects of exoskeletons on the human body. Furthermore, musculoskeletal models can calculate biomechanical loadings of humans with and without exoskeletons for all kinds of applications and allow an evaluation of their purpose. Practical Relevance: This article highlights the possibilities of musculoskeletal models for assessing the design and efficiency of occupational exoskeletons. Several practical use cases are described along with distinct descriptions of common implications of musculoskeletal and exoskeleton modeling. KW - Biomechanics KW - Ergonomics KW - Motion capture KW - Inverse dynamics Y1 - 2022 U6 - https://doi.org/10.1007/s41449-022-00336-4 N1 - Corresponding author: Sebastian Dendorfer VL - 76 IS - 4 SP - 440 EP - 449 PB - Springer Nature ER - TY - JOUR A1 - Weber, Markus A1 - Suess, Franz A1 - Jerabek, Seth A1 - Meyer, Matthias A1 - Grifka, Joachim A1 - Renkawitz, Tobias A1 - Dendorfer, Sebastian T1 - Kinematic pelvic tilt during gait alters functional cup position in total hip arthroplasty JF - Journal of Orthopaedic Research N2 - Static pelvic tilt impacts functional cup position in total hip arthroplasty (THA). In the current study we investigated the effect of kinematic pelvic changes on cup position. In the course of a prospective controlled trial postoperative 3D-computed tomography (CT) and gait analysis before and 6 and 12 months after THA were obtained in 60 patients. Kinematic pelvic motion during gait was measured using Anybody Modeling System. By fusion with 3D-CT, the impact of kinematic pelvic tilt alterations on cup anteversion and inclination was calculated. Furthermore, risk factors correlating with high pelvic mobility were evaluated. During gait a high pelvic range of motion up to 15.6° exceeding 5° in 61.7% (37/60) of patients before THA was found. After surgery, the pelvis tilted posteriorly by a mean of 4.0 ± 6.6° (p < .001). The pelvic anteflexion led to a mean decrease of −1.9 ± 2.2° (p < .001) for cup inclination and −15.1 ± 6.1° (p < .001) for anteversion in relation to the anterior pelvic plane (APP). Kinematic pelvic changes resulted in a further change up to 2.3° for inclination and up to 12.3° for anteversion. In relation to the preoperative situation differences in postoperative cup position ranged from −4.4 to 4.6° for inclination and from −7.8 to 17.9° for anteversion, respectively. Female sex (p < .001) and normal body weight (p < .001) correlated with high alterations in pelvic tilt. Kinematic pelvic changes highly impact cup anteversion in THA. Surgeons using the APP as reference should aim for a higher anteversion of about 15° due to the functional anteflexion of the pelvis during gait. KW - component position KW - gait analysis KW - kinematics KW - pelvic tilt KW - total hip arthroplasty KW - Hüftgelenkprothese KW - Haltungsfehler KW - Hüftgelenkpfanne Y1 - 2021 U6 - https://doi.org/10.1002/jor.25106 SN - 1554-527X VL - 40 IS - 4 SP - 846 EP - 853 PB - Wiley ER - TY - JOUR A1 - Melzner, Maximilian A1 - Suess, Franz A1 - Dendorfer, Sebastian T1 - The impact of anatomical uncertainties on the predictions of a musculoskeletal hand model – a sensitivity study JF - Computer Methods in Biomechanics and Biomedical Engineering N2 - Outputs of musculoskeletal models should be considered probabilistic rather than deterministic as they are affected by inaccuracies and estimations associated with the development of the model. One of these uncertainties being critical for modeling arises from the determination of the muscles' line of action and the physiological cross-sectional area. Therefore, the aim of this study was to evaluate the outcome sensitivity of model predictions from a musculoskeletal hand model in comparison to the uncertainty of these input parameters. For this purpose, the kinematics and muscle activities of different hand movements (abduction of the fingers, abduction of the thumb, and flexion of the thumb) were recorded. One thousand simulations were calculated for each movement using the Latin hypercube sampling method with a corresponding variation of the muscle origin/insertion points and the cross-sectional area. Comparing the standard hand to simulations incorporating uncertainties of input parameters shows no major deviations in on- and off-set time point of muscle activities. About 60% of simulations are located within a ± 30% interval around the standard model concerning joint reaction forces. The comparison with the variation of the input data leads to the conclusion that the standard hand model is able to provide not over-scattered outcomes and, therefore, can be considered relatively stable. These results are of practical importance to the personalization of a musculoskeletal model with subject-specific bone geometries and hence changed muscle line of action. KW - Biomechanik KW - Simulation Y1 - 2021 U6 - https://doi.org/10.1080/10255842.2021.1940974 SN - 1476-8259 N1 - Corresponding author: Maximilian Melzner VL - 25 IS - 2 SP - 156 EP - 164 PB - Taylor & Francis ER - TY - JOUR A1 - Melzner, Maximilian A1 - Pfeiffer, Christian A1 - Suess, Franz A1 - Dendorfer, Sebastian T1 - Musculoskeletal simulation of elbow stability for common injury patterns JF - Journal of Orthopaedic Research N2 - Elbow stability is derived from a combination of muscular, ligamentous, and bony structures. After an elbow trauma the stability of the joint is an important decision criterion for the subsequent treatment. The decision regarding non-operative/operative care depends mostly on subjective assessments of medical experts. Therefore, the aim of this study is to use musculoskeletal simulations as an objective assessment tool to investigate the extent to which failure of different stabilizers affects the elbow stability and how these observations correspond to the assessment from clinical practice. A musculoskeletal elbow simulation model was developed for this aim. To investigate the stability of the elbow, varus/valgus moments were applied under 0°, 45°and 90° flexion while the respective cubital angle was analyzed. This was performed for nine different injury scenarios, which were also evaluated for stability by clinical experts. With the results, it can be determined by which injury pattern and under which flexion angle the elbow stability is impaired regarding varus/valgus moments. The scenario with a complete failure of the medial and lateral ligaments and a fracture of the radial head was identified as having the greatest instability. The study presented a numerical determination of elbow stability against varus/valgus moments regarding clinical injury patterns, as well as a comparison of the numerical outcome with experience gained in clinical practice. The numerical predictions agree well with the assessments of the clinical specialists. Thus, the results from musculoskeletal simulation can make an important contribution to a more objective assessment of the elbow stability. KW - AnyBody KW - musculoskeletal simulation KW - elbow stability Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-54819 SN - 1554-527X N1 - Corresponding author: Maximilian Melzner VL - 41 IS - 6 SP - 1356 EP - 1364 PB - Wiley ER - TY - JOUR A1 - Melzner, Maximilian A1 - Engelhardt, Lucas A1 - Simon, Ulrich A1 - Dendorfer, Sebastian T1 - Electromyography-Based Validation of a Musculoskeletal Hand Model JF - Journal of Biomechanical Engineering N2 - Regarding the prevention of injuries and rehabilitation of the human hand, musculoskeletal simulations using an inverse dynamics approach allow for insights of the muscle recruitment and thus acting forces on the hand. Currently, several hand models from various research groups are in use, which are mainly validated by the comparison of numerical and anatomical moment arms. In contrast to this validation and model-building technique by cadaver studies, the aim of this study is to further validate a recently published hand model [1] by analyzing numerically calculated muscle activities in comparison to experimentally measured electromyographical signals of the muscles. Therefore, the electromyographical signals of 10 hand muscles of five test subjects performing seven different hand movements were measured. The kinematics of these tasks were used as input for the hand model, and the numerical muscle activities were computed. To analyze the relationship between simulated and measured activities, the time difference of the muscle on- and off-set points was calculated, which resulted in a mean on- and off-set time difference of 0.58 s between the experimental data and the model. The largest differences were detected for movements that mainly addressed the wrist. One major issue comparing simulated and measured muscle activities of the hand is cross-talk. Nevertheless, the results show that the hand model fits the experiment quite accurately despite some limitations and is a further step toward patient-specific modeling of the upper extremity. KW - Elektromyographie KW - Biomechanik KW - Simulation KW - Electromyography KW - Muscle KW - Musculoskeletal system KW - Signals KW - Simulation Y1 - 2021 U6 - https://doi.org/10.1115/1.4052115 VL - 144 IS - 2 PB - American Society of Mechanical Engineers, ASME ER - TY - JOUR A1 - Saffert, Anne-Sophie A1 - Melzner, Maximilian A1 - Dendorfer, Sebastian T1 - Biomechanical analysis of the right elevated glenohumeral joint in violinists during legato-playing JF - Technology and Health Care N2 - BACKGROUND: Many statistics reveal that violin players suffer most often from musculoskeletal disorders compared to musicians of other instrument groups. A common phenomenon, especially observed in violin beginners, is the tendency to elevate the right shoulder during playing the violin. This can probably lead to serious disorders in long-term practice with repetitive movements. OBJECTIVE: For this reason, this study investigated the relationship between the right shoulder elevation and the force in the right glenohumeral joint during violin playing. It was hypothesized that the forces in the right glenohumeral joint are higher during playing with the right shoulder raised compared to playing in normal posture. METHODS: Motion capture data from four experienced violinists was recorded and processed by means of musculoskeletal simulation to get the force and elevation angle while playing with raised shoulder and in normal position. RESULTS: The results indicate that the absolute values of the resulting force, as well as the forces in the mediolateral, inferosuperior, and anteroposterior directions, are higher in playing the violin with the shoulder raised than in a normal posture. CONCLUSIONS: Elevating the right shoulder while playing the violin may pose a potential problem. KW - Biomechanische Analyse KW - Schultergelenk KW - Verletzung KW - Violinspiel KW - biomechanics KW - violin KW - shoulder elevation KW - shoulder joint force KW - musculoskeletal disease Y1 - 2022 U6 - https://doi.org/10.3233/THC-219001 N1 - Corresponding author: Anne-Sophie Saffert VL - 30 IS - 1 SP - 177 EP - 186 PB - IOS Press ER - TY - JOUR A1 - Knödler, Samuel A1 - Schliermann, Rainer A1 - Knödler, Leonard A1 - Wu, Mengfan A1 - Hansen, Frederik J. A1 - Matar, Dany Y. A1 - Obed, Doha A1 - Vervoort, Dominique A1 - Haug, Valentin A1 - Hundeshagen, Gabriel A1 - Paik, Angie A1 - Kauke-Navarro, Martin A1 - Kneser, Ulrich A1 - Pomahac, Bohdan A1 - Orgill, Dennis P. A1 - Panayi, Adriana C. T1 - Impact of sarcopenia on outcomes in surgical patients: A systematic review and meta-analysis JF - International journal of surgery N2 - BACKGROUND Surgeons have historically used age as a preoperative predictor of postoperative outcomes. Sarcopenia, the loss of skeletal muscle mass due to disease or biological age, has been proposed as a more accurate risk predictor. The prognostic value of sarcopenia assessment in surgical patients remains poorly understood. Therefore, we aimed to synthesize the available literature and investigate the impact of sarcopenia on peri- and postoperative outcomes across all surgical specialties. METHODS We systematically assessed the prognostic value of sarcopenia on postoperative outcomes by conducting a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searching the PubMed/MEDLINE and EMBASE databases from inception to 1st October 2022. Our primary outcomes were complication occurrence, mortality, length of operation and hospital stay, discharge to home, and postdischarge survival rate at one, three, and five years. Subgroup analysis was performed by stratifying complications according to the Clavien-Dindo classification system. Sensitivity analysis was performed by focusing on studies with an oncological, cardiovascular, emergency, or transplant surgery population, and on those of higher quality or prospective study design. RESULTS A total of 294 studies comprising 97,643 patients, of which 33,070 had sarcopenia, were included in our analysis. Sarcopenia was associated with significantly poorer postoperative outcomes including greater mortality, complication occurrence, length of hospital stay, and lower rates of discharge to home (all P<0.00001). A significantly lower survival rate in patients with sarcopenia was noted at one, three, and five years (all P<0.00001) after surgery. Subgroup analysis confirmed higher rates of complications and mortality in oncological (both P<0.00001), cardiovascular (both P<0.00001), and emergency (P=0.03 and P=0.04, respectively) patients with sarcopenia. In the transplant surgery cohort, mortality was significantly higher in patients with sarcopenia (P<0.00001). Among all patients undergoing surgery for inflammatory bowel disease, the frequency of complications was significantly increased among sarcopenic patients (P=0.007). Sensitivity analysis based on higher-quality studies and prospective studies showed that sarcopenia remained a significant predictor of mortality and complication occurrence (all P<0.00001). CONCLUSION Sarcopenia is a significant predictor of poorer outcomes in surgical patients. Preoperative assessment of sarcopenia can help surgeons to identify patients at risk, critically balance eligibility, and refine perioperative management. Large-scale studies are required to further validate the importance of sarcopenia as a prognostic indicator of perioperative risk, especially in surgical sub-specialties. KW - Sarcopenia KW - Aging KW - Muscle Loss KW - Muscle KW - Surgical Outcomes KW - Surgery Y1 - 2023 U6 - https://doi.org/10.1097/JS9.0000000000000688 PB - Wolters Kluwer ET - accepted ER - TY - JOUR A1 - Knödler, Leonard A1 - Berkin, Özdemir A1 - Moog, Philipp A1 - Prantl, Lukas A1 - Broer, P. Niclas A1 - Knödler, Christoph A1 - Rieger, Ulrich M. A1 - Perl, Markus A1 - von Isenburg, Sarah A1 - Gassner, Ulrich M. A1 - Obed, Doha A1 - Haug, Valentin A1 - Panayi, Adriana C A1 - Knödler, Samuel T1 - Thinking like a Lawyer - Human Rights and Their Association with the Plastic Surgeon of Today JF - Aesthetic Plastic Surgery N2 - Plastic surgeons are trained to perform a wide repertoire of surgeries-ranging from standard local procedures to highly specialized operations. Therefore, plastic surgeons treat a plethora of clinical presentations and address multiple patient needs. Their daily workflow is increasingly entwined with legal topics. The concrete legal interpretation falls within the remit of legal experts. However, by understanding the legal basics of selected surgical procedures, plastic surgeons may generate synergies in patient care and clinical practice. The legal situation is to be elucidated based on the German Basic Law (GBL) and the European Convention on Human Rights (ECHR). KW - European Convention on Human Rights KW - European Law KW - German Basic Law KW - Human Rights KW - Reconstructive Surgery Y1 - 2022 U6 - https://doi.org/10.1007/s00266-022-02990-9 VL - 114 PB - Springer-Verlag GmbH CY - Heidelberg ER - TY - JOUR A1 - Heine, Norbert A1 - Eigenberger, Andreas A1 - Brebant, Vanessa A1 - Kempa, Sally A1 - Seitz, Stephan A1 - Prantl, Lukas A1 - Kuehlmann, Britta T1 - The effect of radiotherapy on fat engraftment for complete breast reconstruction using lipofilling only JF - Archives of Gynecology and Obstetrics N2 - Purpose Lipofilling has been established as a standard technique for contour enhancement following breast reconstruction. However, there is a paucity in current literature regarding the use of this technique for complete reconstruction of the female breast as an alternative to conventional techniques, such as expander or flap-based procedures. In particular, the influence of pre-operative irradiation for successful reconstruction has rarely been examined in published studies. Here, the authors describe their experience with successful fat injection in pre-radiated breasts in comparison with non-pre-radiated patients. Methods In this retrospective study, we examined a total of 95 lipofilling treatments on 26 patients (28 breasts). All of them experienced mastectomy following breast cancer; local breast defects after partial resection of the gland were not included in this study. In total, 47 lipofilling procedures in 12 non-irradiated patients (14 breasts) and 48 procedures in 14 irradiated women (also 14 breasts) were performed. Per session, approximately 297 +/- 112 cc of adipose tissue was grafted in group A (no radiotherapy) and approximately 259 +/- 93 cc was grafted in group B (radiotherapy). Results Among the group of women without pre-operative radiation, 71% of breast reconstructions limited to lipofilling only showed constant engraftment of fat tissue with a successful reconstructive result, whereas only 21% of the patients with pre-radiated breasts showed complete reconstruction of the breast with a permanent fat in-growth. Conclusion Preoperative radiotherapy significantly impedes successful completion of breast reconstructions planned only by autologous fat transfer. Patients should be selected individually and carefully for complete breast reconstruction using lipofilling only. KW - Breast augmentation KW - Breast cancer KW - CANCER KW - Fat graft KW - Lipofilling KW - OUTCOMES KW - PLATELET-RICH PLASMA KW - RADIATION-THERAPY KW - Radiotherapy KW - RECIPIENT-SITE KW - Reconstruction Y1 - 2022 U6 - https://doi.org/10.1007/s00404-022-06610-4 PB - Springer ER - TY - JOUR A1 - Förstl, Nikolas A1 - Süß, Franz A1 - Englert, Carsten A1 - Dendorfer, Sebastian T1 - Design of a reverse shoulder implant to measure shoulder stiffness during implant component positioning JF - Medical Engineering & Physics N2 - To avoid dislocation of the shoulder joint after reverse total shoulder arthroplasty, it is important to achieve sufficient shoulder stability when placing the implant components during surgery. One parameter for assessing shoulder stability can be shoulder stiffness. The aim of this research was to develop a temporary reverse shoulder implant prototype that would allow intraoperative measurement of shoulder stiffness while varying the position of the implant components. Joint angle and torque measurement techniques were developed to determine shoulder stiffness. Hall sensors were used to measure the joint angles by converting the magnetic flux densities into angles. The accuracy of the joint angle measurements was tested using a test bench. Torques were determined by using thin-film pressure sensors. Various mechanical mechanisms for variable positioning of the implant components were integrated into the prototype. The results of the joint angle measurements showed measurement errors of less than 5° in a deflection range of ±15° adduction/abduction combined with ±45° flexion/extension. The proposed design provides a first approach for intra-operative assessment of shoulder stiffness. The findings can be used as a technological basis for further developments. Y1 - 2023 U6 - https://doi.org/10.1016/j.medengphy.2023.104059 N1 - Corresponding author: Sebstian Dendorfer VL - 121 PB - Elsevier ET - Journal Pre-proof 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 - JOUR A1 - Milewski, Nadja A1 - Haug, Sonja T1 - At risk of reproductive disadvantage? Exploring fertility awareness among migrant women in Germany JF - Reproductive Biomedicine & Society Online N2 - This study examined awareness about fertility among immigrant women and non-migrants in Germany. The social relevance of infertility and fertility treatment is increasing in Western countries due to continually low overall birth rates, a high rate of childlessness, and a gap between the desired and actual numbers of children. While there is growing interest in infertility and reproductive medicine in general, previous studies have rarely included immigrant or ethnic minorities in Europe. This study investigated whether knowledge on the age-related fertility decline (ARFD) varies between migrant groups and the majority group, and the role of education. Working hypotheses were drawn from theoretical considerations on frameworks of migrant assimilation. The analysis was based on data collected in a social science pilot study on reproductive medicine, representative of the general population (‘NeWiRe’ 2014–2015). The sample included 962 women aged 18–50 years living in Germany. Approximately 81% of the sample were immigrants who originated from Turkey, Poland, the Balkan countries or countries of the (post-Soviet) Commonwealth of Independent States. While rather poor overall, knowledge on ARFD was found to be significantly lower in the migrant groups compared with the majority group. This minority-group disadvantage cannot be explained by sociodemographic or cultural variables. Future research should include minority groups in empirical studies on awareness about fertility in order to better understand the causes of this disadvantage, and the potential reproductive needs of migrants. KW - Age-related fertility decline KW - Fertility knowledge KW - Migrant assimilation KW - Minority groups KW - Non-patient sample Y1 - 2022 U6 - https://doi.org/10.1016/j.rbms.2021.11.007 VL - 14 SP - 226 EP - 238 PB - Elsevier ER - TY - CHAP A1 - Weber, Karsten T1 - Cybersecurity and Ethics BT - An uncommon yet indispensable combination of issues T2 - The Routledge Handbook of Smart Technologies N2 - The text aims to demonstrate that establishing cybersecurity is not only a technical challenge, but that legal, economic, or organizational aspects also play at least as important a role. The provision of cybersecurity raises ethical questions, since cybersecurity can affect moral values such as autonomy, freedom, or privacy. If measurements necessary for the provision of cybersecurity shall be accepted, it is essential to find a balance between the different claims of all stakeholders involved. This aim is achieved through a detailed ethical analysis accompanied by an extensive literature study. As the most important result of this analysis, it becomes obvious that cybersecurity is in competition or even conflict with other values and interests, and that establishing cybersecurity always involves a trade-off. Not only can there be no 100 percent cybersecurity for technical reasons, but if other values and interests are to be considered, this inevitably leads to compromises in cybersecurity. Y1 - 2022 SN - 9780429351921 U6 - https://doi.org/10.4324/9780429351921-36 SP - 608 EP - 622 PB - Routledge CY - New York ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Course Preparation Time Optimization System for Improved Didactic Outcome T2 - 2022 20th International Conference on Information Technology Based Higher Education and Training (ITHET), 07-09 November 2022, Antalya, Turkey N2 - Due to the various demands for lecturers, there is only a limited time to prepare lectures and lab courses. Therefore, it is necessary to invest the time target-oriented for optimal student learning success. A theoretic model is developed to structure course preparation work regarding scientific content, didactic preparation, and course presentation. Model parameters have to be chosen for each course depending on topic complexity, the lecturer’s prior knowledge, and the already available preparation from the prior semesters. With these parameters, a course preparation model for a complete semester is developed. Analytic models for different optimization strategies are introduced according to the overall goal of the lecturer. Numerical optimization is done to find the appropriate course preparation times to reach an optimal course preparation for high student learning success. It is seen that due to the different optimization strategies, the preparation time results vary and no single truth is given. But this optimization system gives hints on how to invest preparation time target-oriented for high student learning success. KW - Higher education KW - Engineering education KW - Course preparation KW - Curriculum development KW - Optimization Y1 - 2022 SN - 978-1-6654-8908-9 U6 - https://doi.org/10.1109/ITHET56107.2022.10031642 PB - IEEE ER - TY - JOUR A1 - Richter, Stefanie T1 - Integrated Care for People with Dementia BT - Results of a Social-Scientific Evaluation of an Established Dementia Care Model JF - Geriatrics N2 - This article presents results of the social-scientific evaluation of an established care model for people with dementia developed by the professionals as a result of acute problems in care in north-east Germany. In addition to the central elements of the model, the conditions of intersectoral and interprofessional cooperation as well as the qualification profile requirements of the professional groups involved are presented in detail. The results can give suggestions for the organization of integrated care for people with dementia in other countries. Further, the author would hereby like to highlight the gain from the scientific examination of solutions to problems in the field. KW - Demenz KW - Managed Care KW - Dementia KW - Integrated Care Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-22091 VL - 2 IS - 1 SP - 1 EP - 13 PB - MDPI CY - Basel ER - TY - JOUR A1 - Brébant, Vanessa A1 - Weiherer, Maximilian A1 - Noisser, Vivien A1 - Seitz, Stephan A1 - Prantl, Lukas A1 - Eigenberger, Andreas T1 - Implants Versus Lipograft: Analysis of Long-Term Results Following Congenital Breast Asymmetry Correction JF - Aesthetic Plastic Surgery N2 - Aims Congenital breast asymmetry represents a particular challenge to the classic techniques of plastic surgery given the young age of patients at presentation. This study reviews and compares the long-term results of traditional breast augmentation using silicone implants and the more innovative technique of lipografting. Methods To achieve this, we not only captured subjective parameters such as satisfaction with outcome and symmetry, but also objective parameters including breast vol-ume and anthropometric measurements. The objective examination was performed manually and by using the Vectra H2 photogrammetry scanning system. Results Differences between patients undergoing either implant augmentation or lipograft were revealed not to be significant with respect to patient satisfaction with surgical outcome (p= 0.55) and symmetry (p= 0.69). Furthermore, a breast symmetry of 93 % was reported in both groups. Likewise, no statistically significant volume difference between the left and right breasts was observed in both groups (p\0.41). However, lipograft patients needed on average 2.9 procedures to achieve the desired result, compared with 1.3 for implant augmentation. In contrast, patients treated with implant augmentation may require anumber of implant changes during their lifetime. Conclusion Both methods may be considered for patients presenting with congenital breast asymmetry. KW - Congenital Breast Asymmetry KW - 3D volumetry KW - Autologous fat injections KW - Three-dimensional imaging KW - Lipograft Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-32404 VL - 46 SP - 2228 EP - 2236 PB - Springer Nature ER - TY - JOUR A1 - Maier, Johannes A1 - Weiherer, Maximilian A1 - Huber, Michaela A1 - Palm, Christoph T1 - Imitating human soft tissue on basis of a dual-material 3D print using a support-filled metamaterial to provide bimanual haptic for a hand surgery training system JF - Quantitative Imaging in Medicine and Surgery N2 - Background: Currently, it is common practice to use three-dimensional (3D) printers not only for rapid prototyping in the industry, but also in the medical area to create medical applications for training inexperienced surgeons. In a clinical training simulator for minimally invasive bone drilling to fix hand fractures with Kirschner-wires (K-wires), a 3D-printed hand phantom must not only be geometrically but also haptically correct. Due to a limited view during an operation, surgeons need to perfectly localize underlying risk structures only by feeling of specific bony protrusions of the human hand. Methods: The goal of this experiment is to imitate human soft tissue with its haptic and elasticity for a realistic hand phantom fabrication, using only a dual-material 3D printer and support-material-filled metamaterial between skin and bone. We present our workflow to generate lattice structures between hard bone and soft skin with iterative cube edge (CE) or cube face (CF) unit cells. Cuboid and finger shaped sample prints with and without inner hard bone in different lattice thickness are constructed and 3D printed. Results: The most elastic available rubber-like material is too firm to imitate soft tissue. By reducing the amount of rubber in the inner volume through support material (SUP), objects become significantly softer. Without metamaterial, after disintegration, the SUP can be shifted through the volume and thus the body loses its original shape. Although the CE design increases the elasticity, it cannot restore the fabric form. In contrast to CE, the CF design increases not only the elasticity but also guarantees a local limitation of the SUP. Therefore, the body retains its shape and internal bones remain in its intended place. Various unit cell sizes, lattice thickening and skin thickness regulate the rubber material and SUP ratio. Test prints with higher SUP and lower rubber material percentage appear softer and vice versa. This was confirmed by an expert surgeon evaluation. Subjects adjudged pure rubber-like material as too firm and samples only filled with SUP or lattice structure in CE design as not suitable for imitating tissue. 3D-printed finger samples in CF design were rated as realistic compared to the haptic of human tissue with a good palpable bone structure. Conclusions: We developed a new dual-material 3D print technique to imitate soft tissue of the human hand with its haptic properties. Blowy SUP is trapped within a lattice structure to soften rubber-like 3D print material, which makes it possible to reproduce a realistic replica of human hand soft tissue. KW - Dual-material 3D printing KW - Hand surgery training KW - Metamaterial KW - Support material KW - Tissue-imitating hand phantom KW - Handchirurgie KW - 3D-Druck KW - Biomaterial KW - Lernprogramm Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-979 N1 - Corresponding author: Christoph Palm VL - 9 IS - 1 SP - 30 EP - 42 PB - AME Publishing Company ER - TY - CHAP A1 - Weber Nunes, Danilo A1 - Hammer, Michael A1 - Hammer, Simone A1 - Uller, Wibke A1 - Palm, Christoph T1 - Classification of Vascular Malformations Based on T2 STIR Magnetic Resonance Imaging T2 - Bildverarbeitung für die Medizin 2022: Proceedings, German Workshop on Medical Image Computing, Heidelberg, June 26-28, 2022 N2 - Vascular malformations (VMs) are a rare condition. They can be categorized into high-flow and low-flow VMs, which is a challenging task for radiologists. In this work, a very heterogeneous set of MRI images with only rough annotations are used for classification with a convolutional neural network. The main focus is to describe the challenging data set and strategies to deal with such data in terms of preprocessing, annotation usage and choice of the network architecture. We achieved a classification result of 89.47 % F1-score with a 3D ResNet 18. KW - Deep Learning KW - Magnetic Resonance Imaging KW - Vascular Malformations Y1 - 2022 U6 - https://doi.org/10.1007/978-3-658-36932-3_57 SP - 267 EP - 272 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Deserno, Thomas M. A1 - Handels, Heinz A1 - Maier-Hein, Klaus H. A1 - Mersmann, Sven A1 - Palm, Christoph A1 - Tolxdorff, Thomas A1 - Wagenknecht, Gudrun A1 - Wittenberg, Thomas T1 - Viewpoints on Medical Image Processing BT - From Science to Application JF - Current Medical Imaging Reviews N2 - Medical image processing provides core innovation for medical imaging. This paper is focused on recent developments from science to applications analyzing the past fifteen years of history of the proceedings of the German annual meeting on medical image processing (BVM). Furthermore, some members of the program committee present their personal points of views: (i) multi-modality for imaging and diagnosis, (ii) analysis of diffusion-weighted imaging, (iii) model-based image analysis, (iv) registration of section images, (v) from images to information in digital endoscopy, and (vi) virtual reality and robotics. Medical imaging and medical image computing is seen as field of rapid development with clear trends to integrated applications in diagnostics, treatment planning and treatment. KW - Medical imaging KW - Image processing KW - Image analysis KW - Vizualization KW - Multi-modal imaging KW - Diffusion-weighted imaging KW - Model-based imaging KW - Digital endoscopy KW - Bildgebendes Verfahren KW - Bildverarbeitung KW - Medizin Y1 - 2013 U6 - https://doi.org/10.2174/1573405611309020002 VL - 9 IS - 2 SP - 79 EP - 88 ER - TY - JOUR A1 - Noisser, Vivien A1 - Eigenberger, Andreas A1 - Weiherer, Maximilian A1 - Seitz, Stephan A1 - Prantl, Lukas A1 - Brébant, Vanessa T1 - Surgery of congenital breast asymmetry - which objective parameter influences the subjective satisfaction with long-term results JF - Archives of Gynecology and Obstetrics N2 - Purpose Congenital breast asymmetry is a serious gynecological malformation for affected patients. The condition hits young women in puberty and is associated with socio-esthetic handicap, depression, and psychosexual problems. Surgical treatment is usually early in the patient's lifetime, so a long-term sustainable solution is important. Although postoperative outcome has been evaluated in several studies before, this study is the first to analyze which objective parameters have the greatest influence on subjective satisfaction with long-term results. Methods Thirty-four patients diagnosed with congenital breast asymmetry that underwent either lipofilling or implant therapy between the years of 2008 to 2019 were examined. On average, our collective comprised patients seven years after surgery. Data were mainly gathered through manual measurements, patient-reported outcome measures (Breast Q™), and breast volumetry based on 3D scans (Vectra® H2, Canfield Scientific). Results Among all analyzed parameters, only areolar diameter correlated significantly negatively with the subjective outcome satisfaction of the patient. Regarding the subjective assessment of postoperative satisfaction with similarity of the breasts, again the mean areolar diameter, but also the difference in areolar diameter and breast volume between the right and left breasts correlated significantly negatively. Conclusion Areolar diameter was revealed as being a significant factor influencing subjective long-term satisfaction in breast asymmetry patients. Moreover, 3D volumetry proves to be an effective tool to substantiate subjective patient assessments. Our findings may lead to further improvements to surgical planning and will be expanded in further studies. KW - Congenital breast asymmetry KW - Poland syndrome KW - Lipofilling KW - Silicone implant KW - 3D volumetry Y1 - 2021 U6 - https://doi.org/10.1007/s00404-021-06218-0 PB - Springer Nature ER - TY - JOUR A1 - Hartmann, Robin A1 - Weiherer, Maximilian A1 - Schiltz, Daniel A1 - Seitz, Stephan A1 - Lotter, Luisa A1 - Anker, Alexandra A1 - Palm, Christoph A1 - Prantl, Lukas A1 - Brébant, Vanessa T1 - A Novel Method of Outcome Assessment in Breast Reconstruction Surgery: Comparison of Autologous and Alloplastic Techniques Using Three-Dimensional Surface Imaging JF - Aesthetic Plastic Surgery N2 - Background Breast reconstruction is an important coping tool for patients undergoing a mastectomy. There are numerous surgical techniques in breast reconstruction surgery (BRS). Regardless of the technique used, creating a symmetric outcome is crucial for patients and plastic surgeons. Three-dimensional surface imaging enables surgeons and patients to assess the outcome’s symmetry in BRS. To discriminate between autologous and alloplastic techniques, we analyzed both techniques using objective optical computerized symmetry analysis. Software was developed that enables clinicians to assess optical breast symmetry using three-dimensional surface imaging. Methods Twenty-seven patients who had undergone autologous (n = 12) or alloplastic (n = 15) BRS received three-dimensional surface imaging. Anthropomorphic data were collected digitally using semiautomatic measurements and automatic measurements. Automatic measurements were taken using the newly developed software. To quantify symmetry, a Symmetry Index is proposed. Results Statistical analysis revealed that there is no dif- ference in the outcome symmetry between the two groups (t test for independent samples; p = 0.48, two-tailed). Conclusion This study’s findings provide a foundation for qualitative symmetry assessment in BRS using automatized digital anthropometry. In the present trial, no difference in the outcomes’ optical symmetry was detected between autologous and alloplastic approaches. KW - Breast reconstruction KW - Breast symmetry KW - Digital anthropometry KW - Mammoplastik KW - Dreidimensionale Bildverarbeitung KW - Autogene Transplantation KW - Alloplastik Y1 - 2020 U6 - https://doi.org/10.1007/s00266-020-01749-4 VL - 44 SP - 1980 EP - 1987 PB - Springer CY - Heidelberg ER - TY - CHAP A1 - Weber, Joachim A1 - Doenitz, Christian A1 - Brawanski, Alexander A1 - Palm, Christoph T1 - Data-Parallel MRI Brain Segmentation in Clinicial Use BT - Porting FSL-Fastv4 to GPGPUs T2 - Bildverarbeitung für die Medizin 2015; Algorithmen - Systeme - Anwendungen; Proceedings des Workshops vom 15. bis 17. März 2015 in Lübeck N2 - Structural MRI brain analysis and segmentation is a crucial part in the daily routine in neurosurgery for intervention planning. Exemplarily, the free software FSL-FAST (FMRIB’s Segmentation Library – FMRIB’s Automated Segmentation Tool) in version 4 is used for segmentation of brain tissue types. To speed up the segmentation procedure by parallel execution, we transferred FSL-FAST to a General Purpose Graphics Processing Unit (GPGPU) using Open Computing Language (OpenCL) [1]. The necessary steps for parallelization resulted in substantially different and less useful results. Therefore, the underlying methods were revised and adapted yielding computational overhead. Nevertheless, we achieved a speed-up factor of 3.59 from CPU to GPGPU execution, as well providing similar useful or even better results. KW - Brain Segmentation KW - Magnetic Resonance Imaging KW - Parallel Execution KW - Voxel Spacing KW - General Purpose Graphic Processing Unit KW - Kernspintomografie KW - Gehirn KW - Bildsegmentierung KW - Parallelverarbeitung Y1 - 2015 U6 - https://doi.org/10.1007/978-3-662-46224-9_67 SP - 389 EP - 394 PB - Springer CY - Berlin ER - TY - JOUR A1 - Maier, Johannes A1 - Perret, Jerome A1 - Simon, Martina A1 - Schmitt-Rüth, Stephanie A1 - Wittenberg, Thomas A1 - Palm, Christoph T1 - Force-feedback assisted and virtual fixtures based K-wire drilling simulation JF - Computers in Biology and Medicine N2 - One common method to fix fractures of the human hand after an accident is an osteosynthesis with Kirschner wires (K-wires) to stabilize the bone fragments. The insertion of K-wires is a delicate minimally invasive surgery, because surgeons operate almost without a sight. Since realistic training methods are time consuming, costly and insufficient, a virtual-reality (VR) based training system for the placement of K-wires was developed. As part of this, the current work deals with the real-time bone drilling simulation using a haptic force-feedback device. To simulate the drilling, we introduce a virtual fixture based force-feedback drilling approach. By decomposition of the drilling task into individual phases, each phase can be handled individually to perfectly control the drilling procedure. We report about the related finite state machine (FSM), describe the haptic feedback of each state and explain, how to avoid jerking of the haptic force-feedback during state transition. The usage of the virtual fixture approach results in a good haptic performance and a stable drilling behavior. This was confirmed by 26 expert surgeons, who evaluated the virtual drilling on the simulator and rated it as very realistic. To make the system even more convincing, we determined real drilling feed rates through experimental pig bone drilling and transferred them to our system. Due to a constant simulation thread we can guarantee a precise drilling motion. Virtual fixtures based force-feedback calculation is able to simulate force-feedback assisted bone drilling with high quality and, thus, will have a great potential in developing medical applications. KW - Handchirurgie KW - Osteosynthese KW - Operationstechnik KW - Lernprogramm KW - Virtuelle Realität KW - Medical training system KW - Virtual fixtures KW - Virtual reality KW - Force-feedback haptic KW - Minimally invasive hand surgery KW - K-wire drilling Y1 - 2019 U6 - https://doi.org/10.1016/j.compbiomed.2019.103473 N1 - Corresponding author: Christoph Palm VL - 114 SP - 1 EP - 10 PB - Elsevier ER - TY - CHAP A1 - Middel, Luise A1 - Palm, Christoph A1 - Erdt, Marius T1 - Synthesis of Medical Images Using GANs T2 - Uncertainty for safe utilization of machine learning in medical imaging and clinical image-based procedures. First International Workshop, UNSURE 2019, and 8th International Workshop, CLIP 2019, held in conjunction with MICCAI 2019, Shenzhen, China, October 17, 2019 N2 - The success of artificial intelligence in medicine is based on the need for large amounts of high quality training data. Sharing of medical image data, however, is often restricted by laws such as doctor-patient confidentiality. Although there are publicly available medical datasets, their quality and quantity are often low. Moreover, datasets are often imbalanced and only represent a fraction of the images generated in hospitals or clinics and can thus usually only be used as training data for specific problems. The introduction of generative adversarial networks (GANs) provides a mean to generate artificial images by training two convolutional networks. This paper proposes a method which uses GANs trained on medical images in order to generate a large number of artificial images that could be used to train other artificial intelligence algorithms. This work is a first step towards alleviating data privacy concerns and being able to publicly share data that still contains a substantial amount of the information in the original private data. The method has been evaluated on several public datasets and quantitative and qualitative tests showing promising results. KW - Neuronale Netze KW - Deep Learning KW - Generative adversarial networks KW - Machine Learning KW - Artificial Intelligence KW - Data privacy KW - Deep Learning KW - Bilderzeugung KW - Datenschutz Y1 - 2019 SN - 978-3-030-32688-3 U6 - https://doi.org/10.1007/978-3-030-32689-0_13 SN - 0302-9743 SP - 125 EP - 134 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Ebigbo, Alanna A1 - Palm, Christoph A1 - Messmann, Helmut T1 - Barrett esophagus: What to expect from Artificial Intelligence? JF - Best Practice & Research Clinical Gastroenterology N2 - The evaluation and assessment of Barrett’s esophagus is challenging for both expert and nonexpert endoscopists. However, the early diagnosis of cancer in Barrett’s esophagus is crucial for its prognosis, and could save costs. Pre-clinical and clinical studies on the application of Artificial Intelligence (AI) in Barrett’s esophagus have shown promising results. In this review, we focus on the current challenges and future perspectives of implementing AI systems in the management of patients with Barrett’s esophagus. KW - Deep Learning KW - Künstliche Intelligenz KW - Computerunterstützte Medizin KW - Barrett KW - Adenocarcinoma KW - Artificial intelligence KW - Deep learning KW - Convolutional neural networks Y1 - 2021 U6 - https://doi.org/10.1016/j.bpg.2021.101726 SN - 1521-6918 VL - 52-53 IS - June-August PB - Elsevier ER - TY - JOUR A1 - Arribas, Julia A1 - Antonelli, Giulio A1 - Frazzoni, Leonardo A1 - Fuccio, Lorenzo A1 - Ebigbo, Alanna A1 - van der Sommen, Fons A1 - Ghatwary, Noha A1 - Palm, Christoph A1 - Coimbra, Miguel A1 - Renna, Francesco A1 - Bergman, Jacques J.G.H.M. A1 - Sharma, Prateek A1 - Messmann, Helmut A1 - Hassan, Cesare A1 - Dinis-Ribeiro, Mario J. T1 - Standalone performance of artificial intelligence for upper GI neoplasia: a meta-analysis JF - Gut N2 - Objective: Artificial intelligence (AI) may reduce underdiagnosed or overlooked upper GI (UGI) neoplastic and preneoplastic conditions, due to subtle appearance and low disease prevalence. Only disease-specific AI performances have been reported, generating uncertainty on its clinical value. Design: We searched PubMed, Embase and Scopus until July 2020, for studies on the diagnostic performance of AI in detection and characterisation of UGI lesions. Primary outcomes were pooled diagnostic accuracy, sensitivity and specificity of AI. Secondary outcomes were pooled positive (PPV) and negative (NPV) predictive values. We calculated pooled proportion rates (%), designed summary receiving operating characteristic curves with respective area under the curves (AUCs) and performed metaregression and sensitivity analysis. Results: Overall, 19 studies on detection of oesophageal squamous cell neoplasia (ESCN) or Barrett's esophagus-related neoplasia (BERN) or gastric adenocarcinoma (GCA) were included with 218, 445, 453 patients and 7976, 2340, 13 562 images, respectively. AI-sensitivity/specificity/PPV/NPV/positive likelihood ratio/negative likelihood ratio for UGI neoplasia detection were 90% (CI 85% to 94%)/89% (CI 85% to 92%)/87% (CI 83% to 91%)/91% (CI 87% to 94%)/8.2 (CI 5.7 to 11.7)/0.111 (CI 0.071 to 0.175), respectively, with an overall AUC of 0.95 (CI 0.93 to 0.97). No difference in AI performance across ESCN, BERN and GCA was found, AUC being 0.94 (CI 0.52 to 0.99), 0.96 (CI 0.95 to 0.98), 0.93 (CI 0.83 to 0.99), respectively. Overall, study quality was low, with high risk of selection bias. No significant publication bias was found. Conclusion: We found a high overall AI accuracy for the diagnosis of any neoplastic lesion of the UGI tract that was independent of the underlying condition. This may be expected to substantially reduce the miss rate of precancerous lesions and early cancer when implemented in clinical practice. KW - Artificial Intelligence Y1 - 2021 U6 - https://doi.org/10.1136/gutjnl-2020-321922 VL - 70 IS - 8 SP - 1458 EP - 1468 PB - BMJ CY - London ER - TY - JOUR A1 - Palm, Christoph A1 - Axer, Markus A1 - Gräßel, David A1 - Dammers, Jürgen A1 - Lindemeyer, Johannes A1 - Zilles, Karl A1 - Pietrzyk, Uwe A1 - Amunts, Katrin T1 - Towards ultra-high resolution fibre tract mapping of the human brain BT - registration of polarised light images and reorientation of fibre vectors JF - Frontiers in Human Neuroscience N2 - Polarised light imaging (PLI) utilises the birefringence of the myelin sheaths in order to visualise the orientation of nerve fibres in microtome sections of adult human post-mortem brains at ultra-high spatial resolution. The preparation of post-mortem brains for PLI involves fixation, freezing and cutting into 100-μm-thick sections. Hence, geometrical distortions of histological sections are inevitable and have to be removed for 3D reconstruction and subsequent fibre tracking. We here present a processing pipeline for 3D reconstruction of these sections using PLI derived multimodal images of post-mortem brains. Blockface images of the brains were obtained during cutting; they serve as reference data for alignment and elimination of distortion artefacts. In addition to the spatial image transformation, fibre orientation vectors were reoriented using the transformation fields, which consider both affine and subsequent non-linear registration. The application of this registration and reorientation approach results in a smooth fibre vector field, which reflects brain morphology. PLI combined with 3D reconstruction and fibre tracking is a powerful tool for human brain mapping. It can also serve as an independent method for evaluating in vivo fibre tractography. KW - Bildgebendes Verfahren KW - Dreidimensionale Bildverarbeitung KW - Polarisiertes Licht KW - Gehirnkarte Y1 - 2010 U6 - https://doi.org/10.3389/neuro.09.009.2010 VL - 4 ER - TY - CHAP A1 - Weiherer, Maximilian A1 - Zorn, Martin A1 - Wittenberg, Thomas A1 - Palm, Christoph ED - Tolxdorff, Thomas ED - Deserno, Thomas M. ED - Handels, Heinz ED - Maier, Andreas ED - Maier-Hein, Klaus H. ED - Palm, Christoph T1 - Retrospective Color Shading Correction for Endoscopic Images T2 - Bildverarbeitung für die Medizin 2020. Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. März 2020 in Berlin N2 - In this paper, we address the problem of retrospective color shading correction. An extension of the established gray-level shading correction algorithm based on signal envelope (SE) estimation to color images is developed using principal color components. Compared to the probably most general shading correction algorithm based on entropy minimization, SE estimation does not need any computationally expensive optimization and thus can be implemented more effciently. We tested our new shading correction scheme on artificial as well as real endoscopic images and observed promising results. Additionally, an indepth analysis of the stop criterion used in the SE estimation algorithm is provided leading to the conclusion that a fixed, user-defined threshold is generally not feasible. Thus, we present new ideas how to develop a non-parametric version of the SE estimation algorithm using entropy. KW - Endoskopie KW - Bildgebendes Verfahren KW - Farbenraum KW - Graustufe Y1 - 2020 SN - 978-3-658-29266-9 U6 - https://doi.org/10.1007/978-3-658-29267-6 SP - 14 EP - 19 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Wöhl, Rebecca A1 - Huber, Michaela A1 - Loibl, Markus A1 - Riebschläger, Birgit A1 - Nerlich, Michael A1 - Palm, Christoph T1 - The Impact of Semi-Automated Segmentation and 3D Analysis on Testing New Osteosynthesis Material T2 - Bildverarbeitung für die Medizin 2017; Algorithmen - Systeme - Anwendungen; Proceedings des Workshops vom 12. bis 14. März 2017 in Heidelberg N2 - A new protocol for testing osteosynthesis material postoperatively combining semi-automated segmentation and 3D analysis of surface meshes is proposed. By various steps of transformation and measuring, objective data can be collected. In this study the specifications of a locking plate used for mediocarpal arthrodesis of the wrist were examined. The results show, that union of the lunate, triquetrum, hamate and capitate was achieved and that the plate is comparable to coexisting arthrodesis systems. Additionally, it was shown, that the complications detected correlate to the clinical outcome. In synopsis, this protocol is considered beneficial and should be taken into account in further studies. KW - Osteosynthese KW - Implantatwerkstoff KW - Materialprüfung KW - Bildsegmentierung KW - Dreidimensionale Bildverarbeitung Y1 - 2017 U6 - https://doi.org/10.1007/978-3-662-54345-0_30 SP - 122 EP - 127 PB - Springer CY - Berlin ER - TY - JOUR A1 - Wöhl, Rebecca A1 - Maier, Johannes A1 - Gehmert, Sebastian A1 - Palm, Christoph A1 - Riebschläger, Birgit A1 - Nerlich, Michael A1 - Huber, Michaela T1 - 3D Analysis of Osteosyntheses Material using semi-automated CT Segmentation BT - a case series of a 4 corner fusion plate JF - BMC Musculoskeletal Disorders N2 - Backround Scaphoidectomy and midcarpal fusion can be performed using traditional fixation methods like K-wires, staples, screws or different dorsal (non)locking arthrodesis systems. The aim of this study is to test the Aptus four corner locking plate and to compare the clinical findings to the data revealed by CT scans and semi-automated segmentation. Methods: This is a retrospective review of eleven patients suffering from scapholunate advanced collapse (SLAC) or scaphoid non-union advanced collapse (SNAC) wrist, who received a four corner fusion between August 2011 and July 2014. The clinical evaluation consisted of measuring the range of motion (ROM), strength and pain on a visual analogue scale (VAS). Additionally, the Disabilities of the Arm, Shoulder and Hand (QuickDASH) and the Mayo Wrist Score were assessed. A computerized tomography (CT) of the wrist was obtained six weeks postoperatively. After semi-automated segmentation of the CT scans, the models were post processed and surveyed. Results During the six-month follow-up mean range of motion (ROM) of the operated wrist was 60°, consisting of 30° extension and 30° flexion. While pain levels decreased significantly, 54% of grip strength and 89% of pinch strength were preserved compared to the contralateral healthy wrist. Union could be detected in all CT scans of the wrist. While X-ray pictures obtained postoperatively revealed no pathology, two user related technical complications were found through the 3D analysis, which correlated to the clinical outcome. Conclusion Due to semi-automated segmentation and 3D analysis it has been proved that the plate design can keep up to the manufacturers’ promises. Over all, this case series confirmed that the plate can compete with the coexisting techniques concerning clinical outcome, union and complication rate. KW - Handchirurgie KW - Osteosynthese KW - Arthrodese KW - 4FC KW - SLAC wrist KW - SNAC wrist KW - Semi-automated segmentation KW - 3D analysis KW - Computertomographie KW - Bildsegmentierung KW - Dreidimensionale Bildverarbeitung Y1 - 2018 U6 - https://doi.org/10.1186/s12891-018-1975-0 VL - 19 SP - 1 EP - 8 PB - Springer Nature ER - TY - JOUR A1 - Hartmann, Robin A1 - Weiherer, Maximilian A1 - Schiltz, Daniel A1 - Baringer, Magnus A1 - Noisser, Vivien A1 - Hösl, Vanessa A1 - Eigenberger, Andreas A1 - Seitz, Stefan A1 - Palm, Christoph A1 - Prantl, Lukas A1 - Brébant, Vanessa T1 - New aspects in digital breast assessment: further refinement of a method for automated digital anthropometry JF - Archives of Gynecology and Obstetrics N2 - Purpose: In this trial, we used a previously developed prototype software to assess aesthetic results after reconstructive surgery for congenital breast asymmetry using automated anthropometry. To prove the consensus between the manual and automatic digital measurements, we evaluated the software by comparing the manual and automatic measurements of 46 breasts. Methods: Twenty-three patients who underwent reconstructive surgery for congenital breast asymmetry at our institution were examined and underwent 3D surface imaging. Per patient, 14 manual and 14 computer-based anthropometric measurements were obtained according to a standardized protocol. Manual and automatic measurements, as well as the previously proposed Symmetry Index (SI), were compared. Results: The Wilcoxon signed-rank test revealed no significant differences in six of the seven measurements between the automatic and manual assessments. The SI showed robust agreement between the automatic and manual methods. Conclusion: The present trial validates our method for digital anthropometry. Despite the discrepancy in one measurement, all remaining measurements, including the SI, showed high agreement between the manual and automatic methods. The proposed data bring us one step closer to the long-term goal of establishing robust instruments to evaluate the results of breast surgery. KW - digital anthropometry KW - reconstructive surgery KW - 3D surface imaging Y1 - 2021 U6 - https://doi.org/10.1007/s00404-020-05862-2 SN - 1432-0711 VL - 303 SP - 721 EP - 728 PB - Springer Nature CY - Heidelberg ER - TY - JOUR A1 - Brown, Peter A1 - Consortium, RELISH A1 - Zhou, Yaoqi A1 - Palm, Christoph T1 - Large expert-curated database for benchmarking document similarity detection in biomedical literature search JF - Database N2 - Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research. KW - Information Retrieval KW - Indexierung KW - Literaturdatenbank KW - Dokument KW - Ähnlichkeitssuche KW - Suchmaschine Y1 - 2019 U6 - https://doi.org/10.1093/database/baz085 VL - 2019 SP - 1 EP - 66 PB - Oxford University Pres ER - TY - JOUR A1 - Axer, Markus A1 - Amunts, Katrin A1 - Gräßel, David A1 - Palm, Christoph A1 - Dammers, Jürgen A1 - Axer, Hubertus A1 - Pietrzyk, Uwe A1 - Zilles, Karl T1 - Novel Approach to the Human Connectome BT - Ultra-High Resolution Mapping of Fiber Tracts in the Brain JF - NeuroImage N2 - Signal transmission between different brain regions requires connecting fiber tracts, the structural basis of the human connectome. In contrast to animal brains, where a multitude of tract tracing methods can be used, magnetic resonance (MR)-based diffusion imaging is presently the only promising approach to study fiber tracts between specific human brain regions. However, this procedure has various inherent restrictions caused by its relatively low spatial resolution. Here, we introduce 3D-polarized light imaging (3D-PLI) to map the three-dimensional course of fiber tracts in the human brain with a resolution at a submillimeter scale based on a voxel size of 100 μm isotropic or less. 3D-PLI demonstrates nerve fibers by utilizing their intrinsic birefringence of myelin sheaths surrounding axons. This optical method enables the demonstration of 3D fiber orientations in serial microtome sections of entire human brains. Examples for the feasibility of this novel approach are given here. 3D-PLI enables the study of brain regions of intense fiber crossing in unprecedented detail, and provides an independent evaluation of fiber tracts derived from diffusion imaging data. KW - Connectome KW - Human brain KW - Method KW - Polarized light imaging KW - Tractography KW - Systems biology KW - Bildgebendes Verfahren KW - Dreidimensionale Bildverarbeitung KW - Polarisiertes Licht KW - Gehirnkarte Y1 - 2011 U6 - https://doi.org/10.1016/j.neuroimage.2010.08.075 VL - 54 IS - 2 SP - 1091 EP - 1101 ER - TY - JOUR A1 - Ott, Tankred A1 - Palm, Christoph A1 - Vogt, Robert A1 - Oberprieler, Christoph T1 - GinJinn: An object-detection pipeline for automated feature extraction from herbarium specimens JF - Applications in Plant Sciences N2 - PREMISE: The generation of morphological data in evolutionary, taxonomic, and ecological studies of plants using herbarium material has traditionally been a labor-intensive task. Recent progress in machine learning using deep artificial neural networks (deep learning) for image classification and object detection has facilitated the establishment of a pipeline for the automatic recognition and extraction of relevant structures in images of herbarium specimens. METHODS AND RESULTS: We implemented an extendable pipeline based on state-of-the-art deep-learning object-detection methods to collect leaf images from herbarium specimens of two species of the genus Leucanthemum. Using 183 specimens as the training data set, our pipeline extracted one or more intact leaves in 95% of the 61 test images. CONCLUSIONS: We establish GinJinn as a deep-learning object-detection tool for the automatic recognition and extraction of individual leaves or other structures from herbarium specimens. Our pipeline offers greater flexibility and a lower entrance barrier than previous image-processing approaches based on hand-crafted features. KW - Deep Learning KW - herbarium specimens KW - object detection KW - visual recognition KW - Deep Learning KW - Objekterkennung KW - Maschinelles Sehen KW - Pflanzen Y1 - 2020 U6 - https://doi.org/10.1002/aps3.11351 SN - 2168-0450 VL - 8 IS - 6 SP - e11351 PB - Wiley, Botanical Society of America ER - TY - JOUR A1 - Becker, Johanna Sabine A1 - Matusch, Andreas A1 - Palm, Christoph A1 - Salber, Dagmar A1 - Morton, Kathryn A. A1 - Becker, Julia Susanne T1 - Bioimaging of metals in brain tissue by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and metallomics JF - Metallomics N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been developed and established as an emerging technique in the generation of quantitative images of metal distributions in thin tissue sections of brain samples (such as human, rat and mouse brain), with applications in research related to neurodegenerative disorders. A new analytical protocol is described which includes sample preparation by cryo-cutting of thin tissue sections and matrix-matched laboratory standards, mass spectrometric measurements, data acquisition, and quantitative analysis. Specific examples of the bioimaging of metal distributions in normal rodent brains are provided. Differences to the normal were assessed in a Parkinson’s disease and a stroke brain model. Furthermore, changes during normal aging were studied. Powerful analytical techniques are also required for the determination and characterization of metal-containing proteins within a large pool of proteins, e.g., after denaturing or non-denaturing electrophoretic separation of proteins in one-dimensional and two-dimensional gels. LA-ICP-MS can be employed to detect metalloproteins in protein bands or spots separated after gel electrophoresis. MALDI-MS can then be used to identify specific metal-containing proteins in these bands or spots. The combination of these techniques is described in the second section. KW - ICP-Massenspektrometrie KW - Metalle KW - Metallproteide KW - Elektrophorese KW - Gehirn Y1 - 2010 U6 - https://doi.org/10.1039/b916722f IS - 2 SP - 104 EP - 111 PB - Oxford Academic Press ER - TY - CHAP A1 - Maier, Johannes A1 - Huber, Michaela A1 - Katzky, Uwe A1 - Perret, Jerome A1 - Wittenberg, Thomas A1 - Palm, Christoph T1 - Force-Feedback-assisted Bone Drilling Simulation Based on CT Data T2 - Bildverarbeitung für die Medizin 2018; Algorithmen - Systeme - Anwendungen; Proceedings des Workshops vom 11. bis 13. März 2018 in Erlangen N2 - In order to fix a fracture using minimally invasive surgery approaches, surgeons are drilling complex and tiny bones with a 2 dimensional X-ray as single imaging modality in the operating room. Our novel haptic force-feedback and visual assisted training system will potentially help hand surgeons to learn the drilling procedure in a realistic visual environment. Within the simulation, the collision detection as well as the interaction between virtual drill, bone voxels and surfaces are important. In this work, the chai3d collision detection and force calculation algorithms are combined with a physics engine to simulate the bone drilling process. The chosen Bullet-Physics-Engine provides a stable simulation of rigid bodies, if the collision model of the drill and the tool holder is generated as a compound shape. Three haptic points are added to the K-wire tip for removing single voxels from the bone. For the drilling process three modes are proposed to emulate the different phases of drilling in restricting the movement of a haptic device. KW - Handchirurgie KW - Osteosynthese KW - Simulation KW - Lernprogramm Y1 - 2018 U6 - https://doi.org/10.1007/978-3-662-56537-7_78 SP - 291 EP - 296 PB - Springer CY - Berlin ER - TY - GEN A1 - Gräßel, David A1 - Axer, Markus A1 - Palm, Christoph A1 - Dammers, Jürgen A1 - Amunts, Katrin A1 - Pietrzyk, Uwe A1 - Zilles, Karl T1 - Visualization of Fiber Tracts in the Postmortem Human Brain by Means of Polarized Light T2 - NeuroImage KW - Gehirn KW - Bildgebendes Verfahren KW - Polarisiertes Licht KW - Pathologische Anatomie Y1 - 2009 U6 - https://doi.org/10.1016/S1053-8119(09)71415-6 VL - 47 IS - Suppl. 1 SP - 142 ER - TY - JOUR A1 - Osterholt, Tobias A1 - Salber, Dagmar A1 - Matusch, Andreas A1 - Becker, Johanna Sabine A1 - Palm, Christoph T1 - IMAGENA: Image Generation and Analysis BT - An Interactive Software Tool handling LA-ICP-MS Data JF - International Journal of Mass Spectrometry N2 - Metals are involved in many processes of life. They are needed for enzymatic reactions, are involved in healthy processes but also yield diseases if the metal homeostasis is disordered. Therefore, the interest to assess the spatial distribution of metals is rising in biomedical science. Imaging metal (and non-metal) isotopes by laser ablation mass spectrometry with inductively coupled plasma (LA-ICP-MS) requires a special software solution to process raw data obtained by scanning a sample line-by-line. As no software ready to use was available we developed an interactive software tool for Image Generation and Analysis (IMAGENA). Unless optimised for LA-ICP-MS, IMAGENA can handle other raw data as well. The general purpose was to reconstruct images from a continuous list of raw data points, to visualise these images, and to convert them into a commonly readable image file format that can be further analysed by standard image analysis software. The generation of the image starts with loading a text file that holds a data column of every measured isotope. Specifying general spatial domain settings like the data offset and the image dimensions is done by the user getting a direct feedback by means of a preview image. IMAGENA provides tools for calibration and to correct for a signal drift in the y-direction. Images are visualised in greyscale as well a pseudo-colours with possibilities for contrast enhancement. Image analysis is performed in terms of smoothed line plots in row and column direction. KW - LA-ICP-MS KW - ICP-Massenspektrometrie KW - Bilderzeugung KW - Graphische Benutzeroberfläche KW - Image generation KW - Image analysis KW - Graphical user interface Y1 - 2011 U6 - https://doi.org/10.1016/j.ijms.2011.03.010 VL - 307 IS - 1-3 SP - 232 EP - 239 ER - TY - JOUR A1 - Dammers, Jürgen A1 - Axer, Markus A1 - Gräßel, David A1 - Palm, Christoph A1 - Zilles, Karl A1 - Amunts, Katrin A1 - Pietrzyk, Uwe T1 - Signal enhancement in polarized light imaging by means of independent component analysis JF - NeuroImage N2 - Polarized light imaging (PLI) enables the evaluation of fiber orientations in histological sections of human postmortem brains, with ultra-high spatial resolution. PLI is based on the birefringent properties of the myelin sheath of nerve fibers. As a result, the polarization state of light propagating through a rotating polarimeter is changed in such a way that the detected signal at each measurement unit of a charged-coupled device (CCD) camera describes a sinusoidal signal. Vectors of the fiber orientation defined by inclination and direction angles can then directly be derived from the optical signals employing PLI analysis. However, noise, light scatter and filter inhomogeneities interfere with the original sinusoidal PLI signals. We here introduce a novel method using independent component analysis (ICA) to decompose the PLI images into statistically independent component maps. After decomposition, gray and white matter structures can clearly be distinguished from noise and other artifacts. The signal enhancement after artifact rejection is quantitatively evaluated in 134 histological whole brain sections. Thus, the primary sinusoidal signals from polarized light imaging can be effectively restored after noise and artifact rejection utilizing ICA. Our method therefore contributes to the analysis of nerve fiber orientation in the human brain within a micrometer scale. KW - Bildgebendes Verfahren KW - Polarisiertes Licht KW - Signalverarbeitung KW - Signaltrennung KW - Komponentenanalyse KW - Gehirn Y1 - 2010 U6 - https://doi.org/10.1016/j.neuroimage.2009.08.059 VL - 49 IS - 2 SP - 1241 EP - 1248 PB - Elsevier ER - TY - JOUR A1 - Maier, Johannes A1 - Weiherer, Maximilian A1 - Huber, Michaela A1 - Palm, Christoph T1 - Optically tracked and 3D printed haptic phantom hand for surgical training system JF - Quantitative Imaging in Medicine and Surgery N2 - Background: For surgical fixation of bone fractures of the human hand, so-called Kirschner-wires (K-wires) are drilled through bone fragments. Due to the minimally invasive drilling procedures without a view of risk structures like vessels and nerves, a thorough training of young surgeons is necessary. For the development of a virtual reality (VR) based training system, a three-dimensional (3D) printed phantom hand is required. To ensure an intuitive operation, this phantom hand has to be realistic in both, its position relative to the driller as well as in its haptic features. The softest 3D printing material available on the market, however, is too hard to imitate human soft tissue. Therefore, a support-material (SUP) filled metamaterial is used to soften the raw material. Realistic haptic features are important to palpate protrusions of the bone to determine the drilling starting point and angle. An optical real-time tracking is used to transfer position and rotation to the training system. Methods: A metamaterial already developed in previous work is further improved by use of a new unit cell. Thus, the amount of SUP within the volume can be increased and the tissue is softened further. In addition, the human anatomy is transferred to the entire hand model. A subcutaneous fat layer and penetration of air through pores into the volume simulate shiftability of skin layers. For optical tracking, a rotationally symmetrical marker attached to the phantom hand with corresponding reference marker is developed. In order to ensure trouble-free position transmission, various types of marker point applications are tested. Results: Several cuboid and forearm sample prints lead to a final 30 centimeter long hand model. The whole haptic phantom could be printed faultless within about 17 hours. The metamaterial consisting of the new unit cell results in an increased SUP share of 4.32%. Validated by an expert surgeon study, this allows in combination with a displacement of the uppermost skin layer a good palpability of the bones. Tracking of the hand marker in dodecahedron design works trouble-free in conjunction with a reference marker attached to the worktop of the training system. Conclusions: In this work, an optically tracked and haptically correct phantom hand was developed using dual-material 3D printing, which can be easily integrated into a surgical training system. KW - Handchirurgie KW - 3D-Druck KW - Lernprogramm KW - Zielverfolgung KW - HaptiVisT KW - Dual-material 3D printing KW - hand surgery training KW - metamaterial KW - tissue imitating phantom hand Y1 - 2020 U6 - https://doi.org/10.21037/qims.2019.12.03 N1 - Corresponding author: Christoph Palm VL - 10 IS - 02 SP - 340 EP - 455 PB - AME Publishing Company CY - Hong Kong, China ER - TY - CHAP A1 - Glémarec, Yann A1 - Hörmann, Amelie A1 - Lauer, Norina A1 - Buche, Cédric A1 - Lugrin, Jean-Luc A1 - Latoschik, Marc Erich T1 - Towards Virtual Audience Simulation For Speech Therapy T2 - Proceedings of the 23rd ACM International Conference on Intelligent Virtual Agents (IVA '23), Würzburg, September 19 - 22, 2023 N2 - The utilization of virtual reality (VR) technology has shown promise in various therapeutic applications, particularly in exposure therapy for reducing fear of certain situations objects or activities, e.g. fear of height, or negative evaluation of others in social situations. VR has been shown to yield positive outcomes in follow-up studies, and provides a safe and ecological therapeutic environment for therapists and their patients. This paper presents a collaborative effort to develop a VR speech therapy system which simulates a virtual audience for users to practice their public speaking skills. We describe a novel web-based graphica user interface that enables therapists to manage the therapy session using a simple timeline. Lastly, we present the results from a qualitative study with therapists and teachers with functional dysphonia, which highlight the potential of such an application to support and augment the therapists’ work and the remaining challenges regarding the design of natural interactions, agent behaviours and scenario customisation for patients. KW - Stimme KW - Virtuelle Realität Y1 - 2023 SN - 78-1-4503-9994-4 U6 - https://doi.org/10.1145/3570945.3607348 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Becker, Johanna Sabine A1 - Matusch, Andreas A1 - Becker, Julia Susanne A1 - Wu, Bei A1 - Palm, Christoph A1 - Becker, Albert Johann A1 - Salber, Dagmar T1 - Mass spectrometric imaging (MSI) of metals using advanced BrainMet techniques for biomedical research JF - International Journal of Mass Spectrometry N2 - Mass spectrometric imaging (MSI) is a young innovative analytical technique and combines different fields of advanced mass spectrometry and biomedical research with the aim to provide maps of elements and molecules, complexes or fragments. Especially essential metals such as zinc, copper, iron and manganese play a functional role in signaling, metabolism and homeostasis of the cell. Due to the high degree of spatial organization of metals in biological systems their distribution analysis is of key interest in life sciences. We have developed analytical techniques termed BrainMet using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) imaging to measure the distribution of trace metals in biological tissues for biomedical research and feasibility studies—including bioaccumulation and bioavailability studies, ecological risk assessment and toxicity studies in humans and other organisms. The analytical BrainMet techniques provide quantitative images of metal distributions in brain tissue slices which can be combined with other imaging modalities such as photomicrography of native or processed tissue (histochemistry, immunostaining) and autoradiography or with in vivo techniques such as positron emission tomography or magnetic resonance tomography. Prospective and instrumental developments will be discussed concerning the development of the metalloprotein microscopy using a laser microdissection (LMD) apparatus for specific sample introduction into an inductively coupled plasma mass spectrometer (LMD-ICP-MS) or an application of the near field effect in LA-ICP-MS (NF-LA-ICP-MS). These nano-scale mass spectrometric techniques provide improved spatial resolution down to the single cell level. KW - Bioimaging KW - Brain tissue KW - Laser ablation inductively coupled plasma mass spectrometry KW - Laser microdissection inductively coupled plasma mass spectrometry KW - Metals KW - Metallomics KW - Nano-LA-ICP-MS KW - Tumour KW - Massenspektrometrie KW - Bildgebendes Verfahren KW - Metalle KW - Metallproteide KW - Gehirn Y1 - 2011 U6 - https://doi.org/10.1016/j.ijms.2011.01.015 VL - 307 IS - 1-3 SP - 3 EP - 15 PB - eLSEVIER CY - Elsevier ER - TY - CHAP A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Work in Progress: Towards an Academic Secure Software Engineering Curriculum for Engineers T2 - 2020 IEEE Global Engineering Education Conference (EDUCON): 27-30 April 2020, Porto, Portugal N2 - In the age of the Internet of Things, it is becoming increasingly important to integrate knowledge about the development of secure systems (Secure Software Engineering) into academic teaching. However, teaching IT Security and Secure Software Engineering to non-computer scientists is rare. Therefore, we focus our research on the integration of IT Security into software engineering education of non-computer scientists, particularly electrical engineers, by means of inductive teaching- and learning-arrangements. After collecting students' preconceptions of IT Security and Secure Software Engineering in prior work, this paper now contributes with a first mapping of these preconceptions with corresponding learning content as well as suitable inductive teaching methods to be able to create new lecture and exercise units and improve academic learning and teaching in both areas. Y1 - 2020 U6 - https://doi.org/10.1109/EDUCON45650.2020.9125210 SP - 1713 EP - 1717 ER - TY - CHAP A1 - Kampmann, Matthias A1 - Mottok, Jürgen T1 - A ‘laboratory’ as an approach to foster writing skills at software engineering studies learning software engineering is easier when writing courses are directly dpplied to lecture’s content and the problems and examples enrolled in T2 - 2018 IEEE Global Engineering Education Conference, EDUCON 2018, Santa Cruz de Teneriffe, Spanien N2 - Writing, with no doubt, is besides reading a core competency which allows us to "exploit" knowledge in general. It also makes possible the exploration of software engineering's core issues. Especially within this context it is necessary to master the reading of complex texts as well as to be able to write in an appropriate academic expression. With regard to studies in software engineering this seems to be obvious, but in fact the opposite is the reality. Therefore measures to improve these skills seemed to be necessarily applied. At the Ostbayerische Technische Hochschule (OTH, University of Applied Sciences, Regensburg) a new format, the so called c*lab, was installed during the winter semester 2017. This was a course which followed the principle of "Writing Across the Curriculum" (WAC). Organized parallel to a lecture of learning how to program the language C, and addressing students of the first semester, the course was a complete voluntary offer in addition to the general standard courses and lectures of the faculty. Students who participated not only reflected on C and its principles, nor only on writing as a self purpose, but they also learned to express technical thoughts and ideas by the use of didactic methods. The idea to transfer also basic LTeX concepts to write a paper based on the IEEE bare_conf.tex-template were also planned. The course followed the idea of student's-centred learning. This paper presents the main structure, goals, and means of the c*lab, and the theory behind. It also embeds the course within the horizon of experiences of teaching writing skills at the Laboratory for Safe and Secure Systems (LaS 3 ) at the faculty of electronic and information engineering at the OTH Regensburg. First experiences have shown that participants increase writing skills and their idea of the importance of writing. Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363326 SP - 900 EP - 908 ER - TY - CHAP A1 - Tomer, Amir A1 - Hagel, Georg A1 - Mottok, Jürgen A1 - Alt, Dorit A1 - Barak, Miriam I. A1 - Hadar, Irit T1 - CAPELLA: A conceptual framework for adaptive life-long learning T2 - IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece N2 - In this paper we describe a proposed framework for Cooperative Adaptive Personalized Education for Life-long Learning and Activation (CAPELLA). CAPELLA comprises four models: A Knowledge Organization Model, a Learning Process Model, a Community Collaboration Model and a Gaming Model. The underlying pedagogical approach is based on the four pillars of learning: Learning to know, learning to do, learning to collaborate and learning to be. Based on these models and principles, CAPELLA provides a theoretical framework that may assist IT developers to develop state-of-the-art educational platforms and advanced learning applications. Using an example of a UML Diagramming Workshop we demonstrate how CAPELLA incorporates the principles of Adaptive Learning. Y1 - 2017 U6 - https://doi.org/10.1109/EDUCON.2017.7943041 SP - 1463 EP - 1472 ER - TY - CHAP A1 - Birkenmaier, Clemens A1 - Krenkel, Lars ED - Dillmann, Andreas ED - Heller, Gerd ED - Krämer, Ewald ED - Wagner, Claus T1 - Convolutional Neural Networks for Approximation of Blood Flow in Artificial Lungs T2 - New Results in Numerical and Experimental Fluid Mechanics XIII: Contributions to the 22nd STAB/DGLR Symposium N2 - Blood flow in channels of varying diameters <500μm exhibits strong non-linear effects. Multiphase finite volume approaches are feasible, but still computationally costly. Here, the feasibility of applying convolutional neural networks for blood flow prediction in artificial lungs is investigated. Training targets are precomputed using an Eulerian two-phase approach. To match with experimental data, the interphase drag and lift, as well as intraphase shear-thinning are adapted. A recursively branching regression network and convolution/deconvolution networks with plain skip connections and densely connected skips are investigated. A priori knowledge is incorporated in the loss functional to prevent the network from learning non-physical solutions. Inference from neural networks is approximately six orders of magnitude faster than the classical finite volume approach. Even if resulting in comparably coarse flow fields, the neural network predictions can be used as close to convergence initial solutions greatly accelerating classical flow computations. KW - Deep learning fluid mechanics KW - Multiphase blood flow Y1 - 2021 SN - 978-3-030-79560-3 U6 - https://doi.org/10.1007/978-3-030-79561-0_43 IS - 1. Auflage SP - 451 EP - 460 PB - Springer International Publishing CY - Cham ER - TY - JOUR A1 - Scheppach, Markus W. A1 - Rauber, David A1 - Stallhofer, Johannes A1 - Muzalyova, Anna A1 - Otten, Vera A1 - Manzeneder, Carolin A1 - Schwamberger, Tanja A1 - Wanzl, Julia A1 - Schlottmann, Jakob A1 - Tadic, Vidan A1 - Probst, Andreas A1 - Schnoy, Elisabeth A1 - Römmele, Christoph A1 - Fleischmann, Carola A1 - Meinikheim, Michael A1 - Miller, Silvia A1 - Märkl, Bruno A1 - Stallmach, Andreas A1 - Palm, Christoph A1 - Messmann, Helmut A1 - Ebigbo, Alanna T1 - Detection of duodenal villous atrophy on endoscopic images using a deep learning algorithm JF - Gastrointestinal Endoscopy N2 - Background and aims Celiac disease with its endoscopic manifestation of villous atrophy is underdiagnosed worldwide. The application of artificial intelligence (AI) for the macroscopic detection of villous atrophy at routine esophagogastroduodenoscopy may improve diagnostic performance. Methods A dataset of 858 endoscopic images of 182 patients with villous atrophy and 846 images from 323 patients with normal duodenal mucosa was collected and used to train a ResNet 18 deep learning model to detect villous atrophy. An external data set was used to test the algorithm, in addition to six fellows and four board certified gastroenterologists. Fellows could consult the AI algorithm’s result during the test. From their consultation distribution, a stratification of test images into “easy” and “difficult” was performed and used for classified performance measurement. Results External validation of the AI algorithm yielded values of 90 %, 76 %, and 84 % for sensitivity, specificity, and accuracy, respectively. Fellows scored values of 63 %, 72 % and 67 %, while the corresponding values in experts were 72 %, 69 % and 71 %, respectively. AI consultation significantly improved all trainee performance statistics. While fellows and experts showed significantly lower performance for “difficult” images, the performance of the AI algorithm was stable. Conclusion In this study, an AI algorithm outperformed endoscopy fellows and experts in the detection of villous atrophy on endoscopic still images. AI decision support significantly improved the performance of non-expert endoscopists. The stable performance on “difficult” images suggests a further positive add-on effect in challenging cases. KW - celiac disease KW - villous atrophy KW - endoscopy detection KW - artificial intelligence Y1 - 2023 U6 - https://doi.org/10.1016/j.gie.2023.01.006 PB - Elsevier ER - TY - GEN A1 - Birkenmaier, Clemens A1 - Krenkel, Lars T1 - Towards a realistic model of blood viscosity and coagulation in membrane oxygenators T2 - 6th European Conference on Computational Mechanics (Solids, Structures and Coupled Problems) - ECCM 6; 7th European Conference on Computational Fluid Dynamics - ECFD 7 : Glasgow, Scotland, UK, June 11-15, 2018 N2 - Modelling blood flow an shear induced coagulation in membraene oxygenators (MO) is challenging. The relevant geometry of oxygenator fibers (OF) and chaining threads is complex and spans several length scales. In relevant scales and regimes blood shows several significant non-Newtonian effects. Existing models are only capable of accounting for some, but not all relevant effects. Additionally, coagulation processes are influencing fluid properties and geometry significantly. Due to the enormous size of the discretised geometries highly detailed viscosity and coagulation properties of blodd flow in MOs. First step is to find a gemoetry dependent viscosity representation on basis of parametric micro channel experiments with anti-coagulated blood. Next step is a statistic coagulation model, based on micro channel experiments with human (re-calcified citrated) whole blood an evaluation of clinically used osygenators. Since shear rate dependent (i.e. viscosity dependet) coagulation in return influences the viscosity, a combined model with suitable implementation in a RANS framework is necessary. Towards this end, micro channel experiments with new and used single OFs triggering coagulation are performed. Structures of multimeric von Willebrand fibers (vWF), as indicator for shear induced coagulation, are compared to computed and measured flow conditions, using immunofluorescence microscopy, RANS-computations and µPIV, respectively. Preliminary examinations in clinically used MOs show good agreement between occurring structures of vWF, cell depositions and computed flow patterns (geometry form µCT-Scans). However, computed shear rates might be to low to actually trigger activation of vWF. The complex geometry of MOs results in huge meshes, which makes RANS with statistical modelling of viscosity and coagulation a reasonable approach. Towards this end, experimental data on micro channel level with evaluation on real application level is crucial. Especially regarding clotting processes, micro fluidic experiments are powerful research tool. KW - Blood Viscosity KW - Shear Raed Induced Coagulation KW - Membrane Oxygenator Y1 - 2018 ER - TY - JOUR A1 - Knoedler, Leonard A1 - Baecher, Helena A1 - Kauke-Navarro, Martin A1 - Prantl, Lukas A1 - Machens, Hans-Günther A1 - Scheuermann, Philipp A1 - Palm, Christoph A1 - Baumann, Raphael A1 - Kehrer, Andreas A1 - Panayi, Adriana C. A1 - Knoedler, Samuel T1 - Towards a Reliable and Rapid Automated Grading System in Facial Palsy Patients: Facial Palsy Surgery Meets Computer Science JF - Journal of Clinical Medicine N2 - Background: Reliable, time- and cost-effective, and clinician-friendly diagnostic tools are cornerstones in facial palsy (FP) patient management. Different automated FP grading systems have been developed but revealed persisting downsides such as insufficient accuracy and cost-intensive hardware. We aimed to overcome these barriers and programmed an automated grading system for FP patients utilizing the House and Brackmann scale (HBS). Methods: Image datasets of 86 patients seen at the Department of Plastic, Hand, and Reconstructive Surgery at the University Hospital Regensburg, Germany, between June 2017 and May 2021, were used to train the neural network and evaluate its accuracy. Nine facial poses per patient were analyzed by the algorithm. Results: The algorithm showed an accuracy of 100%. Oversampling did not result in altered outcomes, while the direct form displayed superior accuracy levels when compared to the modular classification form (n = 86; 100% vs. 99%). The Early Fusion technique was linked to improved accuracy outcomes in comparison to the Late Fusion and sequential method (n = 86; 100% vs. 96% vs. 97%). Conclusions: Our automated FP grading system combines high-level accuracy with cost- and time-effectiveness. Our algorithm may accelerate the grading process in FP patients and facilitate the FP surgeon’s workflow. Y1 - 2022 U6 - https://doi.org/10.3390/jcm11174998 VL - 11 IS - 17 PB - MDPI CY - Basel ER - TY - CHAP A1 - Mendel, Robert A1 - Rauber, David A1 - Palm, Christoph T1 - Exploring the Effects of Contrastive Learning on Homogeneous Medical Image Data T2 - Bildverarbeitung für die Medizin 2023: Proceedings, German Workshop on Medical Image Computing, July 2– 4, 2023, Braunschweig N2 - We investigate contrastive learning in a multi-task learning setting classifying and segmenting early Barrett’s cancer. How can contrastive learning be applied in a domain with few classes and low inter-class and inter-sample variance, potentially enabling image retrieval or image attribution? We introduce a data sampling strategy that mines per-lesion data for positive samples and keeps a queue of the recent projections as negative samples. We propose a masking strategy for the NT-Xent loss that keeps the negative set pure and removes samples from the same lesion. We show cohesion and uniqueness improvements of the proposed method in feature space. The introduction of the auxiliary objective does not affect the performance but adds the ability to indicate similarity between lesions. Therefore, the approach could enable downstream auto-documentation tasks on homogeneous medical image data. Y1 - 2023 U6 - https://doi.org/10.1007/978-3-658-41657-7 SP - 128 EP - 13 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Hauser, Florian A1 - Grabinger, Lisa A1 - Mottok, Jürgen A1 - Jahn, Sabrina A1 - Nadimpalli, Vamsi Krishna T1 - The Expert’s View: Eye Movement Modeling Examples in Software Engineering Education T2 - Proceedings of the 5th European Conference on Software Engineering Education, Seeon/Germany, June 19 - 21, 2023 N2 - This study investigates the impact of eye movement modeling examples in Software Engineering education. Software Engineering is a highly visual domain. The daily tasks of a software engineer (e.g., formulating requirements, creating UML diagrams, or conducting a code review) require in many cases the use of certain visual strategies. Although these strategies can be found for experts, it has been observed in different eye tracking studies that students have difficulties in learning and applying them. To familiarize students with these visual strategies and to provide them with a better understanding for the cognitive processes involved, a total of seven eye movement modeling examples was created. The seven eye movement modeling examples cover relevant parts of an introductory Software Engineering lecture; they are focused on typical situations in which visual strategies are applied. The results of a questionnaire-based evaluation shows that students consider the eye movement modeling examples as useful, feel supported in their learning process, and would like to see more use of them in the Software Engineering lecture. Furthermore, the students suggested that eye movement modeling examples should also be used in other lectures. Y1 - 2023 SN - 978-1-4503-9956-2 U6 - https://doi.org/10.1145/3593663.3593683 SP - 148 EP - 152 PB - ACM ER - TY - JOUR A1 - Schaeffer, Leon A1 - Herrmann, David A1 - Schratzenstaller, Thomas A1 - Dendorfer, Sebastian A1 - Böhm, Valter T1 - Preliminary theoretical considerations on the stiffness characteristics of a tensegrity joint for the use in dynamic orthoses JF - Journal of Medical Robotics Research N2 - Early motion therapy plays an important role for effective long-term healing of joint injuries. In many cases, conventional dynamic orthoses fail to address the intricate movement possibilities of the underlying joints, limited by their simplistic joint representations, often represented by revolute joints, enabling rotations by only one axis. In this paper, a two-dimensional compliant tensegrity joint for use in biomedical applications is investigated. It consists of two compressed members and five compliant tensioned members. Relative movement possibilities are realized by the intrinsic compliance of the structure. In the development of these systems, the first step is the determination of the static stable equilibrium. This analysis is conducted in this paper by considering the potential energy approach or by using the geometric nonlinear finite element method. The mechanical behavior of the structure is assessed with a specific emphasis on its mechanical compliance. The primary objective of this study is the investigation of the influence of structural parameters on the overall stiffness and movability of the structure. The results underscore the significant effect of member parameters on the stiffness and movability of the compliant tensegrity joint, particularly under varying load magnitudes. These findings provide insights for optimizing the joint’s performance, contributing to its potential application in advanced orthotic and exoskeleton devices. KW - mechanical compliance KW - flexibility ellipsis KW - form-finding KW - tensegrity joint Y1 - 2023 U6 - https://doi.org/10.1142/S2424905X23400081 PB - World Scientific ER - TY - JOUR A1 - Fuhrmann, Thomas A1 - Mandl, Roland A1 - Shamonin (Chamonine), Mikhail T1 - Analysis of learning improvement on changing lab course from single experiments to projects JF - International Journal of Electrical Engineering Education N2 - During recent years, there has been a trend to replace traditional lab courses by project-based learning activities. However, there is currently little scientific evidence for educational improvements through such changes. Some years ago, a lab course on electrical measurements in our bachelor Electrical Engineering and Information Technology was modified from single experiments to projects. This change led to a significant increase in the necessary manpower and lab costs. To justify these higher efforts, it is important to investigate if the learning success increased. We carried out the surveys and collected the statistical data from the students who attended this course. In order to see if the students appreciated this lab course and if there was an objective increase of the students' knowledge, these results were evaluated. Evaluation of the grades in the lecture and lab courses shows that the increase of the students' theoretical and practical knowledge is statistically significant. KW - Electrical engineering education KW - project-based learning KW - student experiments Y1 - 2015 U6 - https://doi.org/10.1177/0020720915583863 VL - 52 IS - 4 SP - 287 EP - 297 PB - SAGE ER - TY - GEN A1 - Rückert, Tobias A1 - Rieder, Maximilian A1 - Rauber, David A1 - Xiao, Michel A1 - Humolli, Eg A1 - Feussner, Hubertus A1 - Wilhelm, Dirk A1 - Palm, Christoph T1 - Augmenting instrument segmentation in video sequences of minimally invasive surgery by synthetic smoky frames T2 - International Journal of Computer Assisted Radiology and Surgery KW - Surgical instrument segmentation KW - smoke simulation KW - unpaired image-to-image translation KW - robot-assisted surgery Y1 - 2023 U6 - https://doi.org/10.1007/s11548-023-02878-2 VL - 18 IS - Suppl 1 SP - S54 EP - S56 PB - Springer Nature ER - TY - JOUR A1 - Kolev, Kalin A1 - Kirchgeßner, Norbert A1 - Houben, Sebastian A1 - Csiszár, Agnes A1 - Rubner, Wolfgang A1 - Palm, Christoph A1 - Eiben, Björn A1 - Merkel, Rudolf A1 - Cremers, Daniel T1 - A variational approach to vesicle membrane reconstruction from fluorescence imaging JF - Pattern Recognition N2 - Biological applications like vesicle membrane analysis involve the precise segmentation of 3D structures in noisy volumetric data, obtained by techniques like magnetic resonance imaging (MRI) or laser scanning microscopy (LSM). Dealing with such data is a challenging task and requires robust and accurate segmentation methods. In this article, we propose a novel energy model for 3D segmentation fusing various cues like regional intensity subdivision, edge alignment and orientation information. The uniqueness of the approach consists in the definition of a new anisotropic regularizer, which accounts for the unbalanced slicing of the measured volume data, and the generalization of an efficient numerical scheme for solving the arising minimization problem, based on linearization and fixed-point iteration. We show how the proposed energy model can be optimized globally by making use of recent continuous convex relaxation techniques. The accuracy and robustness of the presented approach are demonstrated by evaluating it on multiple real data sets and comparing it to alternative segmentation methods based on level sets. Although the proposed model is designed with focus on the particular application at hand, it is general enough to be applied to a variety of different segmentation tasks. KW - 3D segmentation KW - Convex optimization KW - Vesicle membrane analysis KW - Fluorescence imaging KW - Dreidimensionale Bildverarbeitung KW - Bildsegmentierung KW - Konvexe Optimierung Y1 - 2011 U6 - https://doi.org/10.1016/j.patcog.2011.04.019 VL - 44 IS - 12 SP - 2944 EP - 2958 PB - Elsevier ER - TY - CHAP A1 - Seebauer, Stefan A1 - Jahn, Sabrina A1 - Mottok, Jürgen T1 - Learning from Escape Rooms? A Study Design Concept Measuring the Effect of a Cryptography Educational Escape Room T2 - 2020 IEEE Global Engineering Education Conference (EDUCON): 27-30 April 2020, Porto, Portugal N2 - Experts predict that more IT-Security specialists will be needed in the coming years, but in current higher education in engineering disciplines, this topic is hardly addressed. Newer learning methods such as game-based learning (GBL) are enjoying an increasing popularity as their improvement in the education of subject specific topics can be proven by a variety of studies. We chose Educational Escape Rooms (EduER) as a GBL-tool to impart IT-Security in higher education of engineers. In our Escape Room (ER), the students try to solve puzzles and riddles with learned knowledge on the emphasis of cryptography. This paper first deals with a brief introduction to GBL and EduERs, followed by the design of our ER concept, containing different tasks with focus on the topic of cryptography. The tasks cover different cryptographic methods and hash algorithms, e.g. AES, RSA, SHA3. Afterwards the experimental study is presented. The study of the EduER was carried out with students from the bachelor's program in Electrical Engineering and Information Technology at the OTH Regensburg. The participants were divided into three groups of 5 to 8 persons each. They received a briefing with important information, followed by the ER execution, a debriefing afterwards and an exam-like evaluation sheet to test their learned knowledge. Finally, first basic results are presented. Y1 - 2020 U6 - https://doi.org/10.1109/EDUCON45650.2020.9125333 SP - 1684 EP - 1685 ER - TY - CHAP A1 - Klopp, Marco A1 - Gold-Veerkamp, Carolin A1 - Abke, Jörg A1 - Borgeest, Kai A1 - Reuter, Rebecca A1 - Jahn, Sabrina A1 - Mottok, Jürgen A1 - Sedelmaier, Yvonne A1 - Lehmann, Alexander A1 - Landes, Dieter T1 - Totally Different and yet so Alike: Three Concepts to Use Scrum in Higher Education T2 - Proceedings of the 4th European Conference on Software Engineering Education (ECSEE '20): June 2020, Seeon/Bavaria, Germany N2 - Software process models are important in software projects in order to give the work of a project guidelines or a framework. However, teaching process models in higher education seems to be quite challenging. This has to do with the fact that undergraduates have no experience with projects in which process models are used. The theoretical mediation of process models is initially on a very abstract level. For this reason, we chose to combine two didactic approaches, namely problem-based learning and project work. Various traditional plan-driven process models have been expanded in courses in Software Engineering with agile process models. The Scrum Framework is the focus of consideration of this paper. Three Universities of Applied Sciences which cooperate in the EVELIN project focused on Scrum as a process model and integrated it into their teaching. Since the respective concepts of implementation differ, they should be presented and compared in this article to presents some practice approaches. The goal of this presentation of is a uniform evaluation in order to obtain insights from different perspectives. This comparison can draw conclusions for possible necessary improvements of the respective concepts. Y1 - 2020 U6 - https://doi.org/10.1145/3396802.3396817 SP - 12 EP - 21 ER - TY - CHAP A1 - Hauser, Florian A1 - Reuter, Rebecca A1 - Gruber, Hans A1 - Mottok, Jürgen T1 - Research competence: Modification of a questionnaire to measure research competence at universities of applied sciences T2 - IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2018, Santa Cruz de Tenerife, Spain N2 - This paper deals with the validation and modification of the German questionnaire "F-Komp". In its original version, it was intended to measure university students' research competences. In the beginning of this study, there were only a few tools available which were reliable. For the purposes of this study, they were not suitable. At the same time, there was no validated version of the F-Komp available, which made the whole validation process for further usage necessary. This questionnaire is based on a structure, which consist of different skills and knowledge and is focused on measuring research competence in general. The validation and modification of the F-Komp is therefore the aim of our contribution as well as a revised version of the questionnaire. We proceeded an explorative factor and a reliability analysis to do a general evaluation of the tool. Some modifications were done in the questionnaire to make it more suitable to the requirements of technical oriented universities of applied sciences [5]. Our revised version is slightly longer and contains several items to gather data about the participants demographics. The modified questionnaire is based on a more appropriate factor structure. This structure is more practically oriented and pays attention to ethical issues. In future cases, this questionnaire will be used in research oriented courses to measure students' progress in acquiring the knowledge and methods which are necessary to perform as a scientist in different research areas. KW - research oriented teaching KW - research competence KW - competence model KW - modification of a questionnaire Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363216 SP - 109 EP - 117 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 - JOUR A1 - Schecklmann, Martin A1 - Schmausser, Maximilian A1 - Klinger, Felix A1 - Kreuzer, Peter M. A1 - Krenkel, Lars A1 - Langguth, Berthold T1 - Resting motor threshold and magnetic field output of the figure-of-8 and the double-cone coil JF - scientific reports N2 - The use of the double-cone (DC) coil in transcranial magnetic stimulation (TMS) is promoted with the notion that the DC coil enables stimulation of deeper brain areas in contrast to conventional figure-of-8 (Fo8) coils. However, systematic comparisons of these two coil types with respect to the spatial distribution of the magnetic field output and also to the induced activity in superficial and deeper brain areas are limited. Resting motor thresholds of the left and right first dorsal interosseous (FDI) and tibialis anterior (TA) were determined with the DC and the Fo8 coil in 17 healthy subjects. Coils were orientated over the corresponding motor area in an angle of 45 degrees for the hand area with the handle pointing in posterior direction and in medio-lateral direction for the leg area. Physical measurements were done with an automatic gantry table using a Gaussmeter. Resting motor threshold was higher for the leg area in contrast to the hand area and for the Fo8 in contrast to the DC coil. Muscle by coil interaction was also significant providing higher differences between leg and hand area for the Fo8 (about 27%) in contrast to the DC coil (about 15%). Magnetic field strength was higher for the DC coil in contrast to the Fo8 coil. The DC coil produces a higher magnetic field with higher depth of penetration than the figure of eight coil. KW - ANTERIOR CINGULATE CORTEX KW - CONNECTIVITY KW - Depression KW - FRONTAL-CORTEX KW - PREDICTOR KW - RTMS KW - STIMULATION KW - TMS Y1 - 2020 U6 - https://doi.org/10.1038/s41598-020-58034-2 VL - 10 IS - 1 PB - Nature ER - TY - JOUR A1 - Scherzinger, Stefanie T1 - Build your own SQL-on-Hadoop Query Engine A Report on a Term Project in a Master-level Database Course JF - ACM SIGMOD Record N2 - This is a report on a course taught at OTH Regensburg in the summer term of 2018. The students in this course built their own SQL-on-Hadoop engine as a term project in just 8 weeks. miniHive is written in Python and compiles SQL queries into MapReduce workflows. These are then executed on Hadoop. miniHive performs generic query optimizations (selection and projection pushdown, or cost-based join reordering), as well as MapReduce-specific optimizations. The course was taught in English, using a flipped classroom model. The course material was mainly compiled from third-party teaching videos. This report describes the course setup, the miniHive milestones, and gives a short review of the most successful student projects. Y1 - 2019 U6 - https://doi.org/10.1145/3377330.3377336 VL - 48 IS - 2 SP - 33 EP - 38 PB - ACM ER - TY - CHAP A1 - Frikel, Jürgen A1 - Göppel, Simon A1 - Haltmeier, Markus ED - Palm, Christoph T1 - Combining Reconstruction and Edge Detection in Computed Tomography T2 - Bildverarbeitung für die Medizin 2021 : Proceedings, German Workshop on Medical Image Computing: Regensburg, March 7-9, 2021 N2 - We present two methods that combine image reconstruction and edge detection in computed tomography (CT) scans. Our first method is as an extension of the prominent filtered backprojection algorithm. In our second method we employ l1-regularization for stable calculation of the gradient. As opposed to the first method, we show that this approach is able to compensate for undersampled CT data. Y1 - 2021 SN - 978-3-658-33197-9 U6 - https://doi.org/10.1007/978-3-658-33198-6_37 SP - 153 EP - 157 PB - Springer Vieweg CY - Wiesbaden, Germany ER - TY - CHAP A1 - Jahn, Sabrina A1 - Weiss, Nils A1 - Akcakoca, Ugur A1 - Mottok, Jürgen ED - Gómez Chova, L. ED - López Martínez, A. ED - Candel Torres, I. T1 - Under The Hood - A Concept for Virtualized Automotive Security Education T2 - EDULEARN21: Proceedings N2 - In recent years, our society faced a massive interconnection of computer-based everyday objects, which opens these items for cyber-attacks. Dependent on the physical capabilities, successful attacks can vary from data exposure or a loss of functionality to a threat to life and limb. Connected- and autonomous vehicles are extremely safety-critical systems with a huge damage potential. This global trend, together with existing and upcoming regulations (ISO 270xx, ISO 21434, UNECE WP.29, UNECE R155), and the lack of qualified professionals create a tension field for the entire automotive industry. Hence, new education concepts for engineers of safety-critical and connected systems are necessary to secure our daily and future systems against cyber-attacks and raise awareness and knowledge of the topic of IT-Security. Existing automotive security education systems have one common problem: All systems are hardware-based and therefore have very steep learning curves for beginners. Hardware-based systems, in general, are expensive in their initial costs, require regular maintenance, and add diverse operational difficulties independent of the aspired education goal. Additionally, the global pandemic increased the necessity of virtual education concepts for security training in cyber-physical systems. Therefore, we present a novel concept for the education of cyber-security professionals for automotive systems based on discovery and problem-based learning in a virtual learning environment (VLE). Our concept contains individual exercises focusing on the topics of vulnerabilities and attacks in automotive networks and systems. Each exercise relates those topics to the corresponding security goals and countermeasures for mitigation. The learners work collaboratively in a self-contained manner within the VLE to acquire the necessary information to answer questions or find a solution to the given problem. To consider the heterogeneous background (e.g. knowledge, experience, preconceptions) of the learners, the topics can be presented in different difficulties, enabling an adaptable learning environment and different learning trajectories within the exercises. The concept is based on a VLE, consisting of automotive networks and components, which simulate the behavior of a vehicle. This environment provides a hands-on, "real-life" scenario, which allows discovery and problem-based learning in a realistic, but cheap and scalable education environment. Furthermore, virtualization removes common difficulties, always present in training on real hardware. This aims to decrease complexity, prevent learning obstacles related to hardware handling, and enables a location-independent learning environment. The target group of our education concept is Bachelor and Master students of computer science, engineering (e.g. electrical engineering, mechatronics), or similar studies, and (experienced) engineers from the industry. In summary, our publication contains two contributions. We present an adaptable virtual learning environment for automotive security education, combined with an educational concept based on discovery and problem-based learning techniques. The goals of our concept are the education of cyber-security professionals for safety-critical, connected automotive systems and the support of life-long learning reaching from academic education to training in the industry. KW - automotive systems KW - discovery learning KW - higher education KW - inductive teaching KW - problem-based learning KW - security education KW - virtual learning environment Y1 - 2021 SN - 978-84-09-31267-2 U6 - https://doi.org/10.21125/edulearn.2021.1231 SN - 2340-1117 SP - 6109 EP - 6118 ER - TY - JOUR A1 - Kiesl, Hans T1 - Indirect Sampling: A Review of Theory and Recent Applications JF - AStA Wirtschafts- und Sozialstatistisches Archiv N2 - Survey practitioners regularly face the task to draw a sample from a (sub-) population for which no sampling frame exists. Indirect sampling might be a way out in such situations, given that connections exist between the target population and another population for which probability sampling is feasible. While the theory of indirect sampling originated in the context of household panel studies, a wider area of applications emerged during the last decade. We first give a short review of the theory of indirect sampling, show that estimators from indirect samples might have smaller variance than the corresponding direct estimators (contrary to some claims in the literature), summarize recent applications and discuss some issues that are relevant for applying indirect sampling in practice. We also present some theory for unbiased estimation after an additional subsampling stage that was necessary for sampling kindergarten children in the German National Educational Panel Study (NEPS). KW - Bildungserhebung KW - Indirekte Auswahl KW - Stichprobenverfahren Y1 - 2016 U6 - https://doi.org/10.1007/s11943-016-0183-3 VL - 10 IS - 4 SP - 289 EP - 303 PB - Springer ER - TY - JOUR A1 - Joseph, Saskia A1 - Schumm, Michael A1 - Rummel, Otmar A1 - Soska, Alexander A1 - Renschke, Michael A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Schroll-Decker, Irmgard T1 - Teaching finite state machines with case method and role play JF - 2014 IEEE Global Engineering Education Conference (EDUCON 2014) : Istanbul, Turkey, 3 - 5 April 2014 N2 - The professional requirements in Software Engineering have become highly volatile due to the complexities of project development and rapid and innovative changes occurring in the field. Therefore, the development of inter-personal and social competences has gained central importance in the training of software developers. This paper will present a concept allowing to acquire competences by using Case Method and Role Play as instruments in several lectures of Software Engineering. By approaching the issue of competence acquisition on a technical as well as on an educational and social level, life-long learning is facilitated and supported. KW - Case Method KW - competences KW - learning arrangement KW - life-long learning KW - Role Play Y1 - 2013 U6 - https://doi.org/10.1109/EduCon.2013.6530275 SP - 1302 EP - 1305 PB - IEEE ER - TY - JOUR A1 - Birkenmaier, Clemens A1 - Dornia, Christian A1 - Lehle, Karla A1 - Müller, Thomas A1 - Gruber, Michael Andreas A1 - Philipp, Alois A1 - Krenkel, Lars T1 - Analysis of Thrombotic Deposits in Extracorporeal Membrane Oxygenators by High-resolution Microcomputed Tomography: A Feasibility Study JF - ASAIO Journal / American Society for Artificial Internal Organs N2 - Coagulative disorders, especially clotting during extracorporeal membrane oxygenation, are frequent complications. Direct visualization and analysis of deposits in membrane oxygenators using computed tomography (CT) may provide an insight into the underlying mechanisms causing thrombotic events. However, the already established multidetector CT1 (MDCT) method shows major limitations. Here, we demonstrate the feasibility of applying industrial micro-CT (μCT) to circumvent these restrictions. Three clinically used membrane oxygenators were investigated applying both MDCT and μCT. The scans were analyzed in terms of clot volume and local clot distribution. As validation, the clot volume was also determined from the fluid volume, which could be filled into the respective used oxygenator compared to a new device. In addition, cross-sectional CT images were compared with crosscut oxygenators. Based on the μCT findings, a morphological measure (sphericity) for assessing clot structures in membrane oxygenators is introduced. Furthermore, by comparing MDCT and μCT results, an augmentation of the MDCT method is proposed, which allows for improved clot volume determination in a clinical setting. Y1 - 2020 U6 - https://doi.org/10.1097/MAT.0000000000001089 SN - 1538-943X VL - 66 IS - 8 SP - 922 EP - 928 PB - Lippincott Williams & Wilkins 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 - JOUR A1 - Süzeroglu-Melchiors, Sevim A1 - Gassmann, Oliver A1 - Palmié, Maximilian T1 - Friend or foe? The effects of patent attorney use on filing strategy vis-a-vis the effects of firm experience JF - Management Decision N2 - PurposeIn the intellectual property (IP) and management literature, the question of how external patent attorneys impact patent filings has been understudied. The purpose of this paper is to advance this area of research by examining how the use of external patent attorneys influences the patent filing strategies of firms and what impact firms? level of experience with the exclusive use of in-house resources has on filing strategies. This study, thus, provides insights into the strategic dimension behind patent filing, a process which is affected by patent attorneys? work and decision-making processes.Design/methodology/approachThe econometric analysis is based on a patent database of 922,553 patents which is combined with an EPO patent database covering applications from 1990 to 2010. The authors test the hypotheses for this study using patent indicators addressing the impact of in-house firm experience vs the use of external patent attorneys on firm?s filing strategy.FindingsThis research finds empirical evidence that external patent attorneys? work has an effect on patent scope, international scope, and patenting speed. Moreover, it can be shown that external patent attorneys have a positive impact on most filing dimensions, such as patent scope, international scope and the Patent Cooperation Treaty option, whereas the level of in-house firm experience has a negative impact on most filing dimensions. This implies that external patent attorneys seem to pursue a ?maximization approach? while experienced firms seem to pursue a more differentiated approach to filing patents, for instance, drafting narrower and more focused patents.Practical implicationsThe study suggests that effective filing strategies require an integrated approach between diverse IP stakeholders. More particularly, filing strategies should be communicated and aligned between all actors, including external patent attorneys in order to achieve the targeted patenting output.Originality/valueThe current study develops a patent filing typology, which accounts for patent attorneys? decision options. In providing insights into patent attorneys? work and their impacts on intellectual property rights management, the study is a useful complement to prior research, which has predominantly focused on applicants or examiners. KW - Patents KW - Filing strategy KW - Intellectual property management KW - IP Intermediaries KW - Patent attorney KW - Patent strategies KW - Strategic IP mnanagement Y1 - 2017 U6 - https://doi.org/10.1108/MD-01-2016-0047 SN - 0025-1747 VL - 55 IS - 6 SP - 1122 EP - 1142 PB - Emerald ER - TY - JOUR A1 - Rösl, Gerhard A1 - Seitz, Franz T1 - Central Bank Digital Currency and Cash in the Euro Area: Current Developments and one Specific Proposal JF - Credit and Capital Markets – Kredit und Kapital N2 - The present paper provides an overview on current developments of cash usage and issue of central bank digital currency (CBDC) in the euro area and proposes a possible design of a digital euro that allows for instant offline payments. Cash usage at the point-of-sale decreased perceptibly in the past years mainly due to the ongoing trend towards digitalization. However, we show that there are also indications that consumers were somewhat pushed into cashless payments by government regulations and supply-side restrictions by commercial banks. Nonetheless, overall demand for euro cash remained strong and even increased relative to GDP since the financial crisis in 2008. In this process, however, we observe a supply-driven shift towards lower banknote denominations. Central banks all over the world are intensively thinking about the potential issue of ­CBDC as a substitute or complement to cash. Based on some of its preferred characteristics, we propose a double pre-paid scheme combining central elements of TARGET Instant Payment Settlement and electronic money features enabling offline and online instant payments. Since anonymity is categorically discarded by the ECB and as cash has some special advantages from a consumer perspective, the digital euro will rather co-circulate with cash than replace it in transactions. Y1 - 2022 U6 - https://doi.org/10.3790/ccm.55.4.523 VL - 55 IS - 4 SP - 523 EP - 551 PB - Duncker & Humblot CY - Berlin ER - TY - JOUR A1 - Süzeroğlu-Melchiors, Sevim T1 - The supply side of IP management: Understanding firms’ choices regarding IP intermediaries JF - World Patent Information N2 - Studies focusing on the supply side of IP management, particularly on the outsourcing of patent related work, are relatively rare. This paper aims to contribute to the IP literature in two ways. First, a definition of the IP service provider is proposed. Second, I consider three main hypotheses that determine a firm's preference for outsourced IP work. Using data on the outsourcing of patent renewal payments, I found evidence that the choice of IP supplier is affected by: (1) the firm's own IP maintenance capabilities, (2) the firm's IP knowledge utilization, and (3) the IP complexity. KW - Intellectual property (IP) management KW - IP intermediaries KW - IP suppliers KW - Patents Y1 - 2017 U6 - https://doi.org/10.1016/j.wpi.2017.08.002 SN - 0172-2190 VL - 50 SP - 55 EP - 63 PB - Elsevier ER - TY - JOUR A1 - Lingel, Maximilian P. A1 - Haus, Moritz A1 - Paschke, Lukas A1 - Foltan, Maik A1 - Lubnow, Matthias A1 - Gruber, Michael A1 - Krenkel, Lars A1 - Lehle, Karla T1 - Clinical relevance of cell-free DNA during venovenous extracorporeal membrane oxygenation JF - Artificial organs N2 - BACKGROUND: Thrombosis remains a critical complication during venovenous extracorporeal membrane oxygenation (VV ECMO). The involvement of neutrophil extracellular traps (NETs) in thrombogenesis has to be discussed. The aim was to verify NETs in the form of cell-free DNA (cfDNA) in the plasma of patients during ECMO. METHODS: A fluorescent DNA-binding dye (QuantifFluor®, Promega) was used to detect cell-free DNA in plasma samples. cfDNA concentrations from volunteers (n = 21) and patients (n = 9) were compared and correlated with clinical/technical data before/during support, ECMO end and time of a system exchange. RESULTS: Before ECMO, patients with a median (IQR) age of 59 (51/63) years, SOFA score of 11 (10/15), and ECMO run time of 9.0 (7.0/19.5) days presented significantly higher levels of cfDNA compared to volunteers (6.4 (5.8/7.9) ng/μL vs. 5.9 (5.4/6.3) ng/μL; p = 0.044). Within 2 days after ECMO start, cfDNA, inflammatory, and hemolysis parameters remained unchanged, while platelets decreased (p = 0.005). After ECMO removal at the end of therapy, cfDNA, inflammation, and coagulation data (except antithrombin III) remained unchanged. The renewal of a system resulted in known alterations in fibrinogen, d-dimers, and platelets, while cfDNA remained unchanged. CONCLUSION: Detection of cfDNA in plasma of ECMO patients was not an indicator of acute and circuit-induced thrombogenesis. KW - blood KW - cell- free DNA KW - coagulation KW - ECMO KW - inflammation KW - neutrophil extracellular traps Y1 - 2023 U6 - https://doi.org/10.1111/aor.14616 SN - 1525-1594 VL - 47 IS - 11 SP - 1720 EP - 1731 PB - Wiley ER - TY - JOUR A1 - Rückert, Tobias A1 - Rückert, Daniel A1 - Palm, Christoph T1 - Methods and datasets for segmentation of minimally invasive surgical instruments in endoscopic images and videos: A review of the state of the art JF - Computers in Biology and Medicine N2 - In the field of computer- and robot-assisted minimally invasive surgery, enormous progress has been made in recent years based on the recognition of surgical instruments in endoscopic images and videos. In particular, the determination of the position and type of instruments is of great interest. Current work involves both spatial and temporal information, with the idea that predicting the movement of surgical tools over time may improve the quality of the final segmentations. The provision of publicly available datasets has recently encouraged the development of new methods, mainly based on deep learning. In this review, we identify and characterize datasets used for method development and evaluation and quantify their frequency of use in the literature. We further present an overview of the current state of research regarding the segmentation and tracking of minimally invasive surgical instruments in endoscopic images and videos. The paper focuses on methods that work purely visually, without markers of any kind attached to the instruments, considering both single-frame semantic and instance segmentation approaches, as well as those that incorporate temporal information. The publications analyzed were identified through the platforms Google Scholar, Web of Science, and PubMed. The search terms used were “instrument segmentation”, “instrument tracking”, “surgical tool segmentation”, and “surgical tool tracking”, resulting in a total of 741 articles published between 01/2015 and 07/2023, of which 123 were included using systematic selection criteria. A discussion of the reviewed literature is provided, highlighting existing shortcomings and emphasizing the available potential for future developments. KW - Deep Learning KW - Minimal-invasive Chirurgie KW - Bildsegmentierung KW - Surgical instrument segmentation KW - Surgical instrument tracking KW - Spatio-temporal information KW - Endoscopic surgery KW - Robot-assisted surgery Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-69830 N1 - Corresponding author: Tobias Rückert N1 - Corrigendum unter: https://opus4.kobv.de/opus4-oth-regensburg/frontdoor/index/index/docId/7033 VL - 169 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ruewe, Marc A1 - Eigenberger, Andreas A1 - Klein, Silvan A1 - von Riedheim, Antonia A1 - Gugg, Christine A1 - Prantl, Lukas A1 - Palm, Christoph A1 - Weiherer, Maximilian A1 - Zeman, Florian A1 - Anker, Alexandra T1 - Precise Monitoring of Returning Sensation in Digital Nerve Lesions by 3-D Imaging: A Proof-of-Concept Study JF - Plastic and Reconstructive Surgery N2 - Digital nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Yet, available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. However, the precise quantification of AA dynamics by three-dimensional (3-D) imaging could serve as an accurate surrogate to monitor recovery following digital nerve repair. For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. Three dimensional models were composed from raw images that had been acquired with a 3-D camera (Vectra H2) to precisely quantify relative AA for each digit (3-D models, n= 80). Operator properties varied regarding individual experience in 3-D imaging and image processing. Additionally, the concept was applied in a clinical case study. Images taken by experienced photographers were rated better quality (p< 0.001) and needed less processing time (p= 0.020). Quantification of the relative AA was neither altered significantly by experience levels of the photographer (p= 0.425) nor the image assembler (p= 0.749). The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3-D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress. KW - 3D imaging Y1 - 2023 U6 - https://doi.org/10.1097/PRS.0000000000010456 SN - 1529-4242 VL - 152 IS - 4 SP - 670e EP - 674e PB - Lippincott Williams & Wilkins CY - Philadelphia, Pa. ER - TY - GEN A1 - Markov-Glazer, Alon A1 - Schliermann, Rainer ED - Ng, K. ED - Rintala, P. ED - Kandzia, A. ED - Lindeman, A. T1 - Sport psychological Skills Training (PST) in Elite Deaf Sport BT - Diagnostic and other Intervention-related Challenges T2 - The 23rd International Symposium of Adapted Physical Activity (Online ISAPA 2021) and the Nordic Congress of Adapted Physical Activity: 15th-18th June 2021, Jyväskylä, Finland Y1 - 2021 SP - 57 PB - University of Jyväskylä CY - Jyväskylä ER - TY - CHAP A1 - Markov-Glazer, Alon A1 - Schliermann, Rainer ED - Schinke, Robert ED - Chang, Yu-Kai T1 - Psychological skills and techniques utility patterns in elite deaf sport T2 - International Society of Sport Psychology (ISSP), 15th World Congress, Proceedings, 30th September – 4th October 2021, Taipeh, China KW - Deaf sport KW - Deaflympics KW - Hearing impairments KW - Psychological skills Training (PST) Y1 - 2021 SP - 236 EP - 237 PB - Routledge 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 - 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 - 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 - TY - CHAP A1 - Fuhrmann, Thomas T1 - Semi-Structured Lab Projects in Communication Engineering Education T2 - 2023 IEEE Global Engineering Education Conference (EDUCON), 01-04 May 2023, Kuwait N2 - It is generally known that project-based learning is a very important part of engineering education to connect theoretical knowledge with practical work. Students learn to apply their knowledge to real-world challenges as it is the case in their later professional life. If students are not used to project work or the scientific topic is new and relatively complex, they may be overwhelmed. The consequence is that students achieve poor results, are frustrated, and therefore learning success is low. Semi-structured projects are introduced that combine the advantages of structured experiments with projects. The project work is structured into several parts with detailed descriptions of the tasks. In the end, students get similar results to doing a free project, but the success rate is higher due to higher guidance. Therefore, these semi-structured projects are seen to be an appropriate method to guide students to learn how to do project work. The feedback from most students is very positive. Some students with no previous lab experience complained about the project work and wished for more guidance to become familiar with lab work. In sum, the student feedback is encouraging to develop semi-structured projects further. KW - Knowledge engineering KW - Task analysis KW - Communication engineering education Y1 - 2023 U6 - https://doi.org/10.1109/EDUCON54358.2023.10125244 SP - 1 EP - 5 PB - IEEE ER - TY - CHAP A1 - Westner, Markus A1 - Fuhrmann, Thomas A1 - Waas, Thomas A1 - Skelton, David T1 - Internationalization of a Computer Science Faculty BT - Lessons learned from a regional german technical university of applied sciences T2 - 9th Annual International Conference on Computer Science Education: Innovation and Technology (CSEIT 2018), 2018, Singapore N2 - The paper at hand describes how a regional university of applied sciences tried to internationalize its learning and teaching environment. It describes the challenges encountered, the managerial approach taken, illustrates the implemented initiatives, and how effective they turned out. The results might be relevant to faculty staff in managerial positions at regional universities all over the world that face the challenge to internationalize their teaching and learning environment for the benefit of their domestic students. KW - Internationalization KW - Faculty development KW - Change management KW - PDCA KW - Internationalisierung KW - Hochschule für angewandte Wissenschaften KW - Lernumwelt Y1 - 2018 U6 - https://doi.org/10.5176/2251-2195_CSEIT18.118 SP - 33 EP - 38 ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Farmbauer, Michael A1 - Niemetz, Michael T1 - Integrating GNU Radio into a Virtual Course about Communication Systems T2 - 44th International Convention on Information, Communication and Electronic Technology (MIPRO): 27.09. - 01.10.2021, Opatija, Croatia N2 - Due to the COVID-19 pandemic, the course Communication Systems was transferred from presence to a virtual lecture. No hands-on lab experiments were possible. Therefore, a GNU Radio practical part was integrated into the lecture. A tutorial was written to guide students through the first steps with GNU Radio to decrease initial problems and increase student motivation. Several examples were given regarding digital signal processing, analogue and digital modulation and demodulation. Software Defined Radio receivers were set up in the amateur radio lab of the university and connected to the internet so that students were able to get real radio data to be analyzed and demodulated with their own GNU Radio models. This enables a knowledge transfer from simulated signal processing to the analysis and demodulation of real live signals. Students showed medium to high interest in practical examples during the lectures and tried their own GNU Radio simulations. Overall, the integration of GNU Radio and Software Defined Radio receivers into this virtual lecture gave additional benefits for the students to deal with signal processing and demodulation experiments. It is planned to use GNU Radio in the future for complementary practical examples to the hands-on experiments in the lab. KW - Communication engineering education KW - Communication systems KW - Data models KW - Digital modulation KW - Digital signal processing KW - GNU Radio KW - Pandemics KW - radio communication KW - Receivers KW - Software Defined Radio Y1 - 2021 SN - 978-953-233-101-1 U6 - https://doi.org/10.23919/MIPRO52101.2021.9596700 SP - 1565 EP - 1570 PB - IEEE ER - TY - CHAP A1 - Niemetz, Michael A1 - Fuhrmann, Thomas A1 - Farmbauer, Michael T1 - Comprehensive Amateur Radio Education including Public Outreach T2 - IEEE Integrated STEM Education Conference (ISEC), 16-16 March 2019, Princeton, NJ, USA N2 - An amateur radio lecture was developed and is conducted within the general education program of the Ostbayerische Technische Hochschule Regensburg. This course enables the students to participate in a variety of activities within the university. Different learning formats for communication engineering are carried out in combination with an amateur radio station of the university. Additionally, some of the projects serve as anchor points for increased visibility of the university in local society, e.g. by carrying out public events in connection with the local amateur radio community. It is seen that this course together with the amateur radio station have several positive effects for technical education and university visibility. KW - Amateur Radio KW - Antennas KW - Communication engineering education KW - Conferences KW - Education KW - Education Outreach KW - Licenses KW - PROPAGATION KW - radio communication KW - STEM Education Program Y1 - 2019 U6 - https://doi.org/10.1109/ISECon.2019.8882078 SP - 98 EP - 103 PB - IEEE ER - TY - GEN A1 - Scheppach, Markus A1 - Rauber, David A1 - Stallhofer, Johannes A1 - Muzalyova, Anna A1 - Otten, Vera A1 - Manzeneder, Carolin A1 - Schwamberger, Tanja A1 - Wanzl, Julia A1 - Schlottmann, Jakob A1 - Tadic, Vidan A1 - Probst, Andreas A1 - Schnoy, Elisabeth A1 - Römmele, Christoph A1 - Fleischmann, Carola A1 - Meinikheim, Michael A1 - Miller, Silvia A1 - Märkl, Bruno A1 - Palm, Christoph A1 - Messmann, Helmut A1 - Ebigbo, Alanna T1 - Performance comparison of a deep learning algorithm with endoscopists in the detection of duodenal villous atrophy (VA) T2 - Endoscopy N2 - Aims  VA is an endoscopic finding of celiac disease (CD), which can easily be missed if pretest probability is low. In this study, we aimed to develop an artificial intelligence (AI) algorithm for the detection of villous atrophy on endoscopic images. Methods 858 images from 182 patients with VA and 846 images from 323 patients with normal duodenal mucosa were used for training and internal validation of an AI algorithm (ResNet18). A separate dataset was used for external validation, as well as determination of detection performance of experts, trainees and trainees with AI support. According to the AI consultation distribution, images were stratified into “easy” and “difficult”. Results Internal validation showed 82%, 85% and 84% for sensitivity, specificity and accuracy. External validation showed 90%, 76% and 84%. The algorithm was significantly more sensitive and accurate than trainees, trainees with AI support and experts in endoscopy. AI support in trainees was associated with significantly improved performance. While all endoscopists showed significantly lower detection for “difficult” images, AI performance remained stable. Conclusions The algorithm outperformed trainees and experts in sensitivity and accuracy for VA detection. The significant improvement with AI support suggests a potential clinical benefit. Stable performance of the algorithm in “easy” and “difficult” test images may indicate an advantage in macroscopically challenging cases. Y1 - 2023 U6 - https://doi.org/10.1055/s-0043-1765421 VL - 55 IS - S02 PB - Thieme ER - TY - JOUR A1 - Weiherer, Maximilian A1 - Eigenberger, Andreas A1 - Egger, Bernhard A1 - Brébant, Vanessa A1 - Prantl, Lukas A1 - Palm, Christoph T1 - Learning the shape of female breasts: an open-access 3D statistical shape model of the female breast built from 110 breast scans JF - The Visual Computer N2 - We present the Regensburg Breast Shape Model (RBSM)—a 3D statistical shape model of the female breast built from 110 breast scans acquired in a standing position, and the first publicly available. Together with the model, a fully automated, pairwise surface registration pipeline used to establish dense correspondence among 3D breast scans is introduced. Our method is computationally efficient and requires only four landmarks to guide the registration process. A major challenge when modeling female breasts from surface-only 3D breast scans is the non-separability of breast and thorax. In order to weaken the strong coupling between breast and surrounding areas, we propose to minimize the variance outside the breast region as much as possible. To achieve this goal, a novel concept called breast probability masks (BPMs) is introduced. A BPM assigns probabilities to each point of a 3D breast scan, telling how likely it is that a particular point belongs to the breast area. During registration, we use BPMs to align the template to the target as accurately as possible inside the breast region and only roughly outside. This simple yet effective strategy significantly reduces the unwanted variance outside the breast region, leading to better statistical shape models in which breast shapes are quite well decoupled from the thorax. The RBSM is thus able to produce a variety of different breast shapes as independently as possible from the shape of the thorax. Our systematic experimental evaluation reveals a generalization ability of 0.17 mm and a specificity of 2.8 mm. To underline the expressiveness of the proposed model, we finally demonstrate in two showcase applications how the RBSM can be used for surgical outcome simulation and the prediction of a missing breast from the remaining one. Our model is available at https://www.rbsm.re-mic.de/. KW - Statistical shape model KW - Non-rigid surface registration KW - Breast imaging KW - Surgical outcome simulation KW - Breast reconstruction surgery Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-30506 N1 - Corresponding author: Christoph Palm N1 - Zugehörige arXiv-Publikation: https://opus4.kobv.de/opus4-oth-regensburg/frontdoor/index/index/docId/2023 VL - 39 IS - 4 SP - 1597 EP - 1616 PB - Springer Nature 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 - CHAP A1 - Chang, Ching-Sheng A1 - Lin, Jin-Fa A1 - Lee, Ming-Ching A1 - Palm, Christoph ED - Tolxdorff, Thomas ED - Deserno, Thomas M. ED - Handels, Heinz ED - Maier, Andreas ED - Maier-Hein, Klaus H. ED - Palm, Christoph T1 - Semantic Lung Segmentation Using Convolutional Neural Networks T2 - Bildverarbeitung für die Medizin 2020. Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. März 2020 in Berlin N2 - Chest X-Ray (CXR) images as part of a non-invasive diagnosis method are commonly used in today’s medical workflow. In traditional methods, physicians usually use their experience to interpret CXR images, however, there is a large interobserver variance. Computer vision may be used as a standard for assisted diagnosis. In this study, we applied an encoder-decoder neural network architecture for automatic lung region detection. We compared a three-class approach (left lung, right lung, background) and a two-class approach (lung, background). The differentiation of left and right lungs as direct result of a semantic segmentation on basis of neural nets rather than post-processing a lung-background segmentation is done here for the first time. Our evaluation was done on the NIH Chest X-ray dataset, from which 1736 images were extracted and manually annotated. We achieved 94:9% mIoU and 92% mIoU as segmentation quality measures for the two-class-model and the three-class-model, respectively. This result is very promising for the segmentation of lung regions having the simultaneous classification of left and right lung in mind. KW - Neuronales Netz KW - Segmentierung KW - Brustkorb KW - Deep Learning KW - Encoder-Decoder Network KW - Chest X-Ray Y1 - 2020 SN - 978-3-658-29266-9 U6 - https://doi.org/10.1007/978-3-658-29267-6_17 SP - 75 EP - 80 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Philipp, Alois A1 - de Somer, Filip A1 - Foltan, Maik A1 - Bredthauer, Andre A1 - Krenkel, Lars A1 - Zeman, Florian A1 - Lehle, Karla T1 - Life span of different extracorporeal membrane systems for severe respiratory failure in the clinical practice JF - PLOS ONE N2 - Over the past decade, veno-venous extracorporeal membrane oxygenation (vvECMO) has been increasingly utilized in respiratory failure in patients. This study presents our institution´s experience focusing on the life span of ECMO systems reflecting the performance of a particular system. A retrospective review of our ECMO database identified 461 adult patients undergoing vvECMO (2010-2017). Patients that required more than one system and survived the first exchange >24 hours (n = 139) were included. Life span until the first exchange and exchange criteria were analyzed for all systems (PLS, Cardiohelp HLS-set, both Maquet Cardiopulmonary, Rastatt, Germany; Deltastream/Hilite7000LT, iLA-activve, Xenios/NovaLung, Heilbronn, Germany; ECC.O5, LivaNova, Mirandola, Italy). At our ECMO center, the frequency of a system exchange was 30%. The median (IQR) life span was 9 (6-12) days. There was no difference regarding the different systems (p = 0.145 and p = 0.108, respectively). However, the Deltastream systems were exchanged more frequently due to elective technical complications (e. g. worsened gas transfer, development of coagulation disorder, increased bleedings complications) compared to the other exchanged systems (p = 0.013). In summary, the used ECMO systems are safe and effective for acute respiratory failure. There is no evidence for the usage of a specific system. Only the increased predictability of an imminent exchange preferred the usage of a Deltastream system. However, the decision to use a particular system should not depend solely on the possible criteria for an exchange. KW - Equipment Failure Analysis/statistics & numerical data KW - Extracorporeal Membrane Oxygenation/instrumentation KW - Membrane/classification/standards/statistics & numerical data KW - Primary Health Care/statistics & numerical data KW - Respiratory Distress Syndrome/therapy KW - Retrospective Studies KW - Severity of Illness Index KW - Time factors KW - MULTIDETECTOR COMPUTED-TOMOGRAPHY KW - THROMBOTIC DEPOSITS KW - ECMO SYSTEMS KW - Flow KW - OXYGENATION Y1 - 2018 U6 - https://doi.org/10.1371/journal.pone.0198392 VL - 13 IS - 6 SP - 1 EP - 10 PB - PLOS ER - TY - CHAP A1 - Diehl, Andreas A1 - Wolff, Lilli A1 - Fuhrmann, Thomas A1 - Niemetz, Michael A1 - Mörtlbauer, Stefanie A1 - Dirnberger, Sandra T1 - Compact Freshmen Welcome Seminar for Engineering Students T2 - Procedia - Social and Behavioral Sciences N2 - The Faculty of Electrical Engineering and Information Technology of the OTH Regensburg developed and implemented a compact freshmen seminar for the afternoon of the first day of study. The intention of this seminar is to help the freshmen during their transition between school and study without losing lecture time in the first semester. The concept was tested with one small study group at the beginning of the summer semester 2015. To rate the impact of the seminar and to find aspects for continuous improvement an evaluation method was developed and used. Due to the good student resonance during the first run, this introduction seminar was held again in the winter semester 2015/16. It is planned to integrate this seminar as a regular session for all freshmen of the faculty curriculum and monitor the long-term effects of student motivation and success. KW - Engineering Education KW - Freshmen Seminar Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-31034 N1 - Corresponding author: Thomas Fuhrmann IS - 228 SP - 45 EP - 52 PB - Elsevier ER - TY - CHAP A1 - Schaeffer, Leon A1 - Herrmann, David A1 - Böhm, Valter T1 - Theoretical considerations on a 2D compliant tensegrity joint in context of a biomedical application T2 - Engineering for a changing world : 60th ISC, Ilmenau Scientific Colloquium, Technische Universität Ilmenau, September 4-8, 2023 N2 - In this paper, a two-dimensional compliant tensegrity joint was investigated for potential biomedical applications such as orthotics or exoskeletons. The structure consists of two compressed members connected by five compliant tensioned members. The concept is based on the tensegrity principle, which allows the realization of dynamic orthoses without conventional hinge joints. Another advantage is the adaptability to the individual needs of the patient through a suitable design of the structure and the careful selection of the characteristics of the elements. Using geometric nonlinear analysis, the mechanical behavior of the structure was investigated, focusing on mechanical compliance. The main objective was to determine the influence of the initial length and stiffness of the tensioned members and the influence of the magnitude of external forces on the overall stiffness of the movable member of the structure. The results highlight the significant impact of member parameters on the structure's stiffness and movability under varying load magnitudes. The research laid the foundation for future development of dynamic orthoses based on this structure. Y1 - 2023 U6 - https://doi.org/10.22032/dbt.58879 SP - 1 EP - 15 PB - Technische Universität Ilmenau CY - Ilmenau ER - TY - CHAP A1 - Schaeffer, Leon A1 - Herrmann, David A1 - Böhm, Valter T1 - Preliminary considerations on the form-finding of a tensegrity joint to be used in dynamic orthoses T2 - 8th International Conference on Biomedical Engineering and Applications (ICBEA 2024), Tokio, 18-21. March 2024 Y1 - 2024 PB - ACM ET - accepted paper ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Motivation Centered Learning T2 - 2018 IEEE Frontiers in Education Conference (FIE), 3-6 Oct. 2018, San Jose, CA, USA N2 - This Research Work in Progress Paper evaluates students’ motivation sources and shows the high impact that work of professors has on students’ motivation. Common goal of most professors is to help students acquiring knowledge and competencies that are relevant for their further life. From the beginning of Universities’ history, lectures are usually chosen to reach this goal but it is seen in recent years that they are in many cases not the optimal choice. In the last years, many efforts were made to increase students knowledge gain. From learning and motivation psychology research, many details are known how humans remember and transfer knowledge. These research results are used to create new lecture formats to activate students. Research based learning, project based lab courses, problem based learning, feedback systems, flipped classroom, blended learning and gamification in lectures are only some examples for new formats. Common goal of all these new types of learning formats is to increasing students’ motivation and to enhance learning success. In this paper, evaluations using a questionnaire with open questions were done among first year students, bachelor students before graduation and alumni, about their sources of motivation and demotivation. Interesting curricula and lectures with application related topics and possibilities for own work are the main sources of motivation. Enthusiastic professors with high competences and good lecture didactics also contribute to students’ motivation. On the other side, demotivated professors with boring lectures play a much higher role for demotivating students. Therefore, it is necessary to integrate aspects of student motivation into curriculum and lecture design and professors should become aware that they are important role-models for motivating or demotivating students. KW - Computational modeling KW - Electrical engineering KW - Information technology KW - Psychology KW - Social networking (online) KW - Task analysis KW - Urban areas Y1 - 2018 U6 - https://doi.org/10.1109/FIE.2018.8658436 SP - 1 EP - 5 PB - IEEE ER - TY - CHAP A1 - Wick, Michael A1 - Lindner, Gerhard A1 - Zimmer, Katja A1 - Schreiner, Rupert A1 - Fuhrmann, Thomas A1 - Seebauer, Gudrun A1 - Xu, Boqing A1 - Zheng, Jihong A1 - Wang, Ning ED - Liu, Xu ED - Zhang, Xi-Cheng T1 - German-Chinese cooperative Bachelor in engineering physics/optoelectronics T2 - 14th Conference on Education and Training in Optics and Photonics: ETOP 2017; Hangzhou, China 29.05.2017 - 31.05.2017 N2 - The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further. Y1 - 2017 SN - 9781510613812 U6 - https://doi.org/10.1117/12.2269943 PB - SPIE ER - TY - JOUR A1 - Kratzer, Simon A1 - Westner, Markus A1 - Strahringer, Susanne T1 - Traction with fraction: Strategic IS management in SMEs through Fractional CIOs JF - International Journal of Information Systems and Project Management N2 - Small and medium-sized enterprises (SMEs) increasingly need to manage nformation technology (IT) effectively in order to remain competitive. However, compared to larger organizations, SMEs often face challenges in terms of resources and employer attractiveness, and regularly do not have the need to employ a Chief Information Officer (CIO) on a full-time basis. To address this issue, a growing number of global experts have begun to provide CIO services on a part-time basis for multiple clients simultaneously. This approach allows SMEs to tap into the expertise of experienced IT leaders at a fraction of the cost and without committing to long-term arrangements. While these professionals, known as “Fractional CIOs”, have proven their value in the field, there has been a lack of academic research on this emerging trend. Therefore, we carried out a comprehensive research project between 2020 and 2023, involving 62 Fractional CIOs from 10 countries. The research produced a definition, different types of engagements, and success factors for Fractional CIOs and their engagements. This paper summarizes these findings for a wider audience of academics and practitioners. KW - Fractional CIO KW - Chief Information Officer KW - SMEs KW - small businesses Y1 - 2024 U6 - https://doi.org/10.12821/ijispm120101 SN - 2182-7788 VL - 12 IS - 1 SP - 5 EP - 16 ER - TY - JOUR A1 - Westner, Markus A1 - Kratzer, Simon A1 - Drechsler, Andreas A1 - Strahringer, Susanne T1 - The Fractional CIO in SMEs: conceptualization and research agenda JF - Information Systems and e-Business Management N2 - We conceptualize the new phenomenon of the Fractional Chief InformationOfficer (CIO) as a part-time executive who usually works for more than one pri-marily small- to medium-sized enterprise (SME) and develop promising avenuesfor future research on Fractional CIOs. We conduct an empirical study by drawingon semi-structured interviews with 40 individuals from 10 different countries whooccupy a Fractional CIO role. We derive a definition for the Fractional CIO, dis-tinguish it from other forms of employment, and compare it with existing researchon CIO roles. Further, we find four salient engagement types of Fractional CIOsoffering value for SMEs in various situations: Strategic IT management, Restruc-turing, Rapid scaling, and Hands-on support. The results reveal similarities withexisting CIO roles as well as novel insights concerning the different engagementtypes. Lastly, we propose a research agenda for the Fractional CIO field, based onfour research themes derived from existing CIO research and insights from theinterviews. KW - Fractional CIO KW - Virtual CIO KW - IT leadership KW - Part-time management KW - SMEs KW - Small businesses KW - Interim management Y1 - 2022 U6 - https://doi.org/10.1007/s10257-022-00557-4 VL - 20 SP - 581 EP - 611 PB - Springer ER - TY - JOUR A1 - Bartsch, Alexander A1 - Beham, Daniela A1 - Gebhardt, Jakob A1 - Ehrlich, Ingo A1 - Schratzenstaller, Thomas A1 - Monkman, Gareth J. T1 - Mechanical Properties of NdPrFeB Based Magnetoactive Bisphenol-Free Boron-Silicate Polymers JF - Journal of Nanomedicine and Nanotechnology N2 - Following a ban on many materials containing bisphenol-A, new bisphenol-free Boron silicates have been found as substitutes. The purpose of this study is to describe the mechanical properties of these bisphenol-free magnetoactive borosilicate polymers containing hard magnetic particles. Samples of 0%, 33% and 66% by wt. were loaded for compression using a universal testing machine. The maximum forces occurring for different travel speeds were compared before and after post-magnetization treatments. The post-magnetization included 2 stages. In addition, the change in mechanical properties within 24 hours after the post-magnetization process was investigated. Furthermore, the influence of speed and particle content were investigated. In general, there is a correlation between the required compressive force and, the level of post-magnetization stress, the increase in travel speed and particle content in the boron silicate. Comparison of the non-post-magnetized and post-magnetized samples using two-tailed t-tests shows that the p-values for all weight fraction changes in NdPrFeB particles and travel speeds are less than 0.001. Also, a comparison between tests in which the traverse speed was varied also showed significant changes in the resulting compression forces. The same is valid for changes in the weight ratio of the NdPrFeB particles in the samples. For post-magnetized samples, no significant difference can be observed in the first 24 hours following magnetization. In summary, the material presents viscoelastic, plastic force-displacement behavior, which can be well recognized by its bi-linear curve shape. The investigation shows that borosilicate polymers based on NdPrFeB can have their mechanical behavior modified and controlled by post-magnetization processes. This opens new possibilities for many future applications. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-67425 UR - https://www.walshmedicalmedia.com/open-access/mechanical-properties-of-ndprfeb-based-magnetoactive-bisphenolfree-boronsilicate-polymers-124385.html SN - 2157-7439 N1 - Corresponding author: Alexander Bartsch VL - 14 IS - 6 PB - Walsh Medical Media ER - TY - JOUR A1 - Koenig, Eric A1 - Guertler, Katherine T1 - One Size Does Not Fit All: Individuality and Perceptions of Improvement and Satisfaction Among TE Students JF - English Teaching & Learning N2 - Academic self-regulation is a key factor for motivation and learning achievement. Yet with the large range of individual factors, this is not a one-size-fits-all proposition. This study of L2 Technical English students at two German universities explored learners’ expectations and motivations, in particular regarding self-regulation and self-efficacy via the individual’s time investment in self-led study. In an initial survey, learners (N=1646) reported on their English skill levels and anticipated learning habits. Complementarily, the retrospective survey investigated learners’ (N=796) actual behavior during the course, their perceptions of language skill improvement, and their satisfaction. The initial survey indicates a clear understanding that time investment in self-regulated study will lead to greater improvement, an outcome confirmed in the retrospective survey. Additionally, students who invested more time in their coursework were more satisfied with their achievement, although most learners acknowledge they should have studied more. The results verify that learners recognize the nexus between self-regulation and language skill improvement, yet university students are not satisfied with their capacity to self-regulate their language learning strategies. While differences in students’ skill levels and academic self-efficacy result in divergent degrees of progress, students of all types report benefits to their language skills when motivated to self-regulated study. KW - English KW - Technical English KW - Self-efficacy KW - Self-regulation KW - Motivation Y1 - 2021 U6 - https://doi.org/10.1007/s42321-021-00076-4 SN - 1023-7267 VL - 45 IS - 3 SP - 303 EP - 324 PB - Springer Science and Business Media ER - TY - GEN A1 - Scheppach, Markus W. A1 - Mendel, Robert A1 - Probst, Andreas A1 - Meinikheim, Michael A1 - Palm, Christoph A1 - Messmann, Helmut A1 - Ebigbo, Alanna T1 - Artificial Intelligence (AI) – assisted vessel and tissue recognition during third space endoscopy (Smart ESD) T2 - Zeitschrift für Gastroenterologie N2 - Clinical setting  Third space procedures such as endoscopic submucosal dissection (ESD) and peroral endoscopic myotomy (POEM) are complex minimally invasive techniques with an elevated risk for operator-dependent adverse events such as bleeding and perforation. This risk arises from accidental dissection into the muscle layer or through submucosal blood vessels as the submucosal cutting plane within the expanding resection site is not always apparent. Deep learning algorithms have shown considerable potential for the detection and characterization of gastrointestinal lesions. So-called AI – clinical decision support solutions (AI-CDSS) are commercially available for polyp detection during colonoscopy. Until now, these computer programs have concentrated on diagnostics whereas an AI-CDSS for interventional endoscopy has not yet been introduced. We aimed to develop an AI-CDSS („Smart ESD“) for real-time intra-procedural detection and delineation of blood vessels, tissue structures and endoscopic instruments during third-space endoscopic procedures. Characteristics of Smart ESD  An AI-CDSS was invented that delineates blood vessels, tissue structures and endoscopic instruments during third-space endoscopy in real-time. The output can be displayed by an overlay over the endoscopic image with different modes of visualization, such as a color-coded semitransparent area overlay, or border tracing (demonstration video). Hereby the optimal layer for dissection can be visualized, which is close above or directly at the muscle layer, depending on the applied technique (ESD or POEM). Furthermore, relevant blood vessels (thickness> 1mm) are delineated. Spatial proximity between the electrosurgical knife and a blood vessel triggers a warning signal. By this guidance system, inadvertent dissection through blood vessels could be averted. Technical specifications  A DeepLabv3+ neural network architecture with KSAC and a 101-layer ResNeSt backbone was used for the development of Smart ESD. It was trained and validated with 2565 annotated still images from 27 full length third-space endoscopic videos. The annotation classes were blood vessel, submucosal layer, muscle layer, electrosurgical knife and endoscopic instrument shaft. A test on a separate data set yielded an intersection over union (IoU) of 68%, a Dice Score of 80% and a pixel accuracy of 87%, demonstrating a high overlap between expert and AI segmentation. Further experiments on standardized video clips showed a mean vessel detection rate (VDR) of 85% with values of 92%, 70% and 95% for POEM, rectal ESD and esophageal ESD respectively. False positive measurements occurred 0.75 times per minute. 7 out of 9 vessels which caused intraprocedural bleeding were caught by the algorithm, as well as both vessels which required hemostasis via hemostatic forceps. Future perspectives  Smart ESD performed well for vessel and tissue detection and delineation on still images, as well as on video clips. During a live demonstration in the endoscopy suite, clinical applicability of the innovation was examined. The lag time for processing of the live endoscopic image was too short to be visually detectable for the interventionist. Even though the algorithm could not be applied during actual dissection by the interventionist, Smart ESD appeared readily deployable during visual assessment by ESD experts. Therefore, we plan to conduct a clinical trial in order to obtain CE-certification of the algorithm. This new technology may improve procedural safety and speed, as well as training of modern minimally invasive endoscopic resection techniques. KW - Artificial Intelligence KW - Medical Image Computing KW - Endoscopy KW - Bildgebendes Verfahren KW - Medizin KW - Künstliche Intelligenz KW - Endoskopie Y1 - 2022 U6 - https://doi.org/10.1055/s-0042-1755110 VL - 60 IS - 08 PB - Georg Thieme Verlag CY - Stuttgart ER - TY - GEN A1 - Meinikheim, Michael A1 - Mendel, Robert A1 - Scheppach, Markus W. A1 - Probst, Andreas A1 - Prinz, Friederike A1 - Schwamberger, Tanja A1 - Schlottmann, Jakob A1 - Gölder, Stefan Karl A1 - Walter, Benjamin A1 - Steinbrück, Ingo A1 - Palm, Christoph A1 - Messmann, Helmut A1 - Ebigbo, Alanna T1 - INFLUENCE OF AN ARTIFICIAL INTELLIGENCE (AI) BASED DECISION SUPPORT SYSTEM (DSS) ON THE DIAGNOSTIC PERFORMANCE OF NON-EXPERTS IN BARRETT´S ESOPHAGUS RELATED NEOPLASIA (BERN) T2 - Endoscopy N2 - Aims Barrett´s esophagus related neoplasia (BERN) is difficult to detect and characterize during endoscopy, even for expert endoscopists. We aimed to assess the add-on effect of an Artificial Intelligence (AI) algorithm (Barrett-Ampel) as a decision support system (DSS) for non-expert endoscopists in the evaluation of Barrett’s esophagus (BE) and BERN. Methods Twelve videos with multimodal imaging white light (WL), narrow-band imaging (NBI), texture and color enhanced imaging (TXI) of histologically confirmed BE and BERN were assessed by expert and non-expert endoscopists. For each video, endoscopists were asked to identify the area of BERN and decide on the biopsy spot. Videos were assessed by the AI algorithm and regions of BERN were highlighted in real-time by a transparent overlay. Finally, endoscopists were shown the AI videos and asked to either confirm or change their initial decision based on the AI support. Results Barrett-Ampel correctly identified all areas of BERN, irrespective of the imaging modality (WL, NBI, TXI), but misinterpreted two inflammatory lesions (Accuracy=75%). Expert endoscopists had a similar performance (Accuracy=70,8%), while non-experts had an accuracy of 58.3%. When AI was implemented as a DSS, non-expert endoscopists improved their diagnostic accuracy to 75%. Conclusions AI may have the potential to support non-expert endoscopists in the assessment of videos of BE and BERN. Limitations of this study include the low number of videos used. Randomized clinical trials in a real-life setting should be performed to confirm these results. KW - Artificial Intelligence KW - Barrett's Esophagus KW - Speiseröhrenkrankheit KW - Künstliche Intelligenz KW - Diagnose Y1 - 2022 U6 - https://doi.org/10.1055/s-00000012 VL - 54 IS - S 01 SP - S39 PB - Thieme ER - TY - JOUR A1 - Scheppach, Markus W. A1 - Mendel, Robert A1 - Probst, Andreas A1 - Meinikheim, Michael A1 - Palm, Christoph A1 - Messmann, Helmut A1 - Ebigbo, Alanna T1 - ARTIFICIAL INTELLIGENCE (AI) – ASSISTED VESSEL AND TISSUE RECOGNITION IN THIRD-SPACE ENDOSCOPY JF - Endoscopy N2 - Aims Third-space endoscopy procedures such as endoscopic submucosal dissection (ESD) and peroral endoscopic myotomy (POEM) are complex interventions with elevated risk of operator-dependent adverse events, such as intra-procedural bleeding and perforation. We aimed to design an artificial intelligence clinical decision support solution (AI-CDSS, “Smart ESD”) for the detection and delineation of vessels, tissue structures, and instruments during third-space endoscopy procedures. Methods Twelve full-length third-space endoscopy videos were extracted from the Augsburg University Hospital database. 1686 frames were annotated for the following categories: Submucosal layer, blood vessels, electrosurgical knife and endoscopic instrument. A DeepLabv3+neural network with a 101-layer ResNet backbone was trained and validated internally. Finally, the ability of the AI system to detect visible vessels during ESD and POEM was determined on 24 separate video clips of 7 to 46 seconds duration and showing 33 predefined vessels. These video clips were also assessed by an expert in third-space endoscopy. Results Smart ESD showed a vessel detection rate (VDR) of 93.94%, while an average of 1.87 false positive signals were recorded per minute. VDR of the expert endoscopist was 90.1% with no false positive findings. On the internal validation data set using still images, the AI system demonstrated an Intersection over Union (IoU), mean Dice score and pixel accuracy of 63.47%, 76.18% and 86.61%, respectively. Conclusions This is the first AI-CDSS aiming to mitigate operator-dependent limitations during third-space endoscopy. Further clinical trials are underway to better understand the role of AI in such procedures. KW - Artificial Intelligence KW - Third-Space Endoscopy KW - Smart ESD Y1 - 2022 U6 - https://doi.org/10.1055/s-0042-1745037 VL - 54 IS - S01 SP - S175 PB - Thieme ER - TY - JOUR A1 - Hartmann, Robin A1 - Nieberle, Felix A1 - Palm, Christoph A1 - Brébant, Vanessa A1 - Prantl, Lukas A1 - Kuehle, Reinald A1 - Reichert, Torsten E. A1 - Taxis, Juergen A1 - Ettl, Tobias T1 - Utility of Smartphone-based Three-dimensional Surface Imaging for Digital Facial Anthropometry JF - JPRAS Open N2 - Background The utilization of three-dimensional (3D) surface imaging for facial anthropometry is a significant asset for patients undergoing maxillofacial surgery. Notably, there have been recent advancements in smartphone technology that enable 3D surface imaging. In this study, anthropometric assessments of the face were performed using a smartphone and a sophisticated 3D surface imaging system. Methods 30 healthy volunteers (15 females and 15 males) were included in the study. An iPhone 14 Pro (Apple Inc., USA) using the application 3D Scanner App (Laan Consulting Corp., USA) and the Vectra M5 (Canfield Scientific, USA) were employed to create 3D surface models. For each participant, 19 anthropometric measurements were conducted on the 3D surface models. Subsequently, the anthropometric measurements generated by the two approaches were compared. The statistical techniques employed included the paired t-test, paired Wilcoxon signed-rank test, Bland–Altman analysis, and calculation of the intraclass correlation coefficient (ICC). Results All measurements showed excellent agreement between smartphone-based and Vectra M5-based measurements (ICC between 0.85 and 0.97). Statistical analysis revealed no statistically significant differences in the central tendencies for 17 of the 19 linear measurements. Despite the excellent agreement found, Bland–Altman analysis revealed that the 95% limits of agreement between the two methods exceeded ±3 mm for the majority of measurements. Conclusion Digital facial anthropometry using smartphones can serve as a valuable supplementary tool for surgeons, enhancing their communication with patients. However, the proposed data suggest that digital facial anthropometry using smartphones may not yet be suitable for certain diagnostic purposes that require high accuracy. KW - Three-dimensional surface imaging KW - Stereophotogrammetry KW - Smartphone-based surface imaging KW - Digital anthropometry KW - Facial anthropometry Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-70348 VL - 39 SP - 330 EP - 343 PB - Elsevier ER -