3,074 results on '"Böcker, A."'
Search Results
2. Mid-term functional outcome (minimum 24 months, mean 4 years) after locking plate osteosynthesis for displaced fractures of the proximal humerus in 557 cases
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Rouven Neudeck, Mark Philipp Daferner, Evi Fleischhacker, Tobias Helfen, Fabian Gilbert, Wolfgang Böcker, Ben Ockert, and Georg Siebenbürger
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General Earth and Planetary Sciences ,General Environmental Science - Published
- 2023
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3. Frakturen des Talushalses und -Corpus
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Sebastian F. Baumbach, Wolfgang Böcker, and Hans Polzer
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- 2023
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4. Frakturen des Sprunggelenkes
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S. F. Baumbach, W. Böcker, and H. Polzer
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Orthopedics and Sports Medicine - Published
- 2023
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5. Osteoporose: Diagnostik und Behandlung
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Ulla Stumpf, Moritz Kraus, Roland Ladurner, Carl Neuerburg, and Wolfgang Böcker
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Surgeons ,Issues, ethics and legal aspects ,Health (social science) ,Orthopedics ,Bone Density Conservation Agents ,Germany ,Quality of Life ,Humans ,Osteoporosis ,Geriatrics and Gerontology ,Gerontology - Abstract
Osteoporosis is the most common systemic skeletal disease worldwide. Its consequences have a substantial impact on the quality of life of patients and increases the overall morbidity and mortality. Standardized diagnostic procedures and treatment recommendations have been available for years as German and international (S3) guidelines. Nevertheless, there is a considerable gap in the diagnosis and adequate treatment of osteoporosis, especially in Germany. The aim is to detect the disease at an early stage and to establish a specific and consistent treatment of osteoporosis. In this way the quality of life and independence of those affected can be maintained over a long period. In the acute and permanent treatment of manifest osteoporosis, surgeons, orthopedic and trauma surgeons play a key role.Weltweit ist die Volkskrankheit Osteoporose die häufigste systemische Skeletterkrankung. In ihren Folgen hat sie erheblichen Einfluss auf die Lebensqualität der Betroffenen, aber auch auf die Morbidität und Mortalität. Seit Jahren stehen ein standardisiertes diagnostisches Vorgehen und Therapieempfehlungen mittels deutschsprachiger und auch internationaler (S3-)Leitlinien zur Verfügung. Trotzdem besteht, vor allem in Deutschland, eine erhebliche Lücke in der Diagnose und adäquaten Behandlung der Osteoporose. Ziel ist es, ein frühzeitiges Erkennen und eine konsequente Behandlung der Osteoporose zu etablieren, um so Lebensqualität und Selbstständigkeit der Betroffenen langfristig zu erhalten. In der Behandlung der manifesten Osteoporose nehmen Chirurgen, Unfallchirurgen und Orthopäden eine Schlüsselposition ein.
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- 2023
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6. Wissenschaftskommunikation und Informationsverhalten während der COVID-19-Pandemie: Eine Analyse von Umfragedaten und Interviews
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Ramona Böcker, Thomas Mandl, Hannah Mitera, and Franziska Schmidt
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Library and Information Sciences ,Information Systems - Abstract
Zusammenfassung Die Coronapandemie hat einen hohen Bedarf an Informationen ausgelöst. Gleichzeitig wurde eine große Menge an Wissenschaftsinformationen über verschiedene Kanäle verbreitet, darunter häufig auch über Social Media. Somit entstanden für die Forschung zum Informationsverhalten neue Chancen zur Beobachtung von Nutzenden, aber auch neue methodische Herausforderungen, dieses Verhalten mit dem sonstigen Konsum von Nachrichten und Wissenschaftskommunikation in Bezug zu setzen. Es wird ein Mixed-Methods-Ansatz aus einer Befragung zur Nutzung und Bewertung von Informationsquellen kombiniert mit Beobachtungen aus einer Nutzungsstudie vorgestellt Für diese wurden in einem Experiment Ergebnislisten verschiedener Web- und Videosuchen als Ausgangspunkt genutzt, um Auswahlmethoden und Qualitätskriterien für Wissenschaftskommunikate zu ermitteln. Beide methodischen Ansätze zeigten, dass die Seriosität und die Bekanntheit einer Quelle eine dominierende Rolle bei Auswahlentscheidungen spielen.
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- 2023
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7. Run-to-Failure Relay Dataset for Predictive Maintenance Research With Machine Learning
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Fabian Winkel, Johannes Deuse-Kleinsteuber, and Joachim Böcker
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Electrical and Electronic Engineering ,Safety, Risk, Reliability and Quality - Published
- 2023
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8. Holistic Enlightening of Blackspots With Passive Tailorable Reflecting Surfaces for Efficient Urban mmWave Networks
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Simon Häger, Karsten Heimann, Stefan Böcker, and Christian Wietfeld
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General Computer Science ,General Engineering ,General Materials Science ,Electrical and Electronic Engineering - Published
- 2023
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9. Novel Tape Suture Osteosynthesis for Hyperextension Injuries of the Subaxial Cervical Spine: A Biomechanical Study
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BECKER, CHRISTOPHER A., KUHLEIN, TITUS, WALTER, SANDY, KISTLER, MANUEL, BRUDER, JAN, RUBENBAUER, BIANKA, GREINER, AXEL, BÖCKER, WOLFGANG, and CAVALCANTI KUßMAUL, ADRIAN
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Pharmacology ,Cancer Research ,Sutures ,Iatrogenic Disease ,Cervical Vertebrae ,Humans ,General Biochemistry, Genetics and Molecular Biology ,Research Article ,Biomechanical Phenomena ,Diskectomy - Abstract
Background/Aim: Anterior tension band injuries are usually the result of high impact hyperextension trauma. Current surgical treatment includes anterior cervical discectomy and fusion bearing the risk of soft tissue irritation, degeneration of adjacent cervical segments, implant failure or iatrogenic spondylodesis. This study examined the biomechanical properties of tape suture constructs reenforcing ligamental stability for the treatment of Association of Osteosynthesis (AO) type B3 injuries compared to anterior fusion. Materials and Methods: After creation of an AO type B3 injury in synthetic cervical segments (C5/6, Sawbone(®)), seven segments were treated with anterior fusion and seven with a tape suture construct, similar to the SpeedBridge™ (Arthrex(®)). Biomechanical testing was performed, simulating extension, flexion, lateral bending, and rotation. Dislocation (˚) and corresponding force (N) were measured and compared. Results: Anterior fusion displayed a mean range of extension, lateral bending, and rotation of 3.60˚ (SD 1.87˚), 2.28˚ (SD 1.55˚), and 2.81˚ (SD 0.78˚), respectively. The tape suture showed a mean range of extension, lateral bending, and rotation of 4.24˚ (SD 0.81˚) (p=0.146), 5.44˚ (SD 1.56˚) (p=0.013), and 5.29˚ (SD 1.44˚) (p
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- 2023
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10. Safe drilling zones for anteriorly, central, and posteriorly angulated syndesmotic stabilization devices
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S. F. Baumbach, A. Synek, F. T. Spindler, L. Bauer, W. Böcker, and H. Polzer
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Orthopedics and Sports Medicine ,Surgery - Abstract
Purpose The purposes of the study were to (1) analyze the shape of the distal fibula at the location of syndesmotic stabilization and to (2) define safe zones at the distal-lateral fibula for three different drilling tunnel orientations: anteriorly-, posteriorly angulated and center-center. Methods Postoperative, bilateral CT images of adult patients that underwent syndesmotic stabilization (suture-button system) for an acute, unilateral ankle injury were analyzed. Manual axial CT reconstructions of the uninjured side were generated. First, the axial shape of the distal fibula was classified. The aspect ratio between the anterio-lateral and the posterior-lateral surfaces of the fibula was calculated to assess symmetry. Second, the same axial planes were used to define the safe zones. Each drilling-tunnel orientation (anterior, central, posterior) comprised a fixed medial tibial anchor point and a safe zone on the lateral fibula. For each of the three orientations, the most anteriorly and posteriorly drilling tunnel location was simulated. Next to a cumulative visual analysis, a quantitative analysis of the most anterior and posterior point on the anterio- and posterior-lateral surfaces was calculated. Results A total of 96 CT datasets were analyzed. (1) 81% of fibulae revealed a triangular convex-, 10% an irregular-, and 8% a quadrilateral shape. The lateral surface ratio was 1.0 ± 0.2 (range: 0.7–1.5), not differing between the fibula types (n.s.). (2) The safe corridor on the lateral surface of the fibula for an anteriorly angulated drilling tunnel was − 8% to − 41%, for a posteriorly angulated drilling tunnel was 0% to 46%, and for a center-center alignment − 7 ± 11% (range: − 28 to 18%). Conclusion The meta-diaphyseal region of the distal fibula revealed a homogeneous crosssectional shape. The lateral apex of the fibula can serve as a landmark defining safe zones to place the drilling tunnels correctly. Applying these safe zones in clinical practice could help to avoid the misplacement of the syndesmotic fixation device. Level of evidence Level III, retrospective radiographic study.
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- 2022
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11. First documentation of golden jackal (Canis aureus) reproduction in Germany
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Felix Böcker, Hannah Weber, and Sebastian Collet
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Animal Science and Zoology ,Ecology, Evolution, Behavior and Systematics - Abstract
The golden jackal (Canis aureus), a mesocarnivore, is currently expanding from eastern towards western Europe. Reproduction of the species could be confirmed in several areas in central Europe in recent years. This study collects the first records of golden jackal reproduction in Germany in 2021 and 2022. A family group of at least five individuals could be confirmed using camera traps and scat surveys with a trained detection dog and subsequent genetic identification in 2021. In 2022, camera traps confirmed a second reproduction in the same area.
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- 2022
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12. 'High ankle block' for surgery at the ankle joint
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Klaus F, Hofmann-Kiefer, Federico, Gaube, Philipp, Groene, Wolfgang, Böcker, Hans, Polzer, and Sebastian F, Baumbach
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Orthopedics and Sports Medicine - Abstract
Surgery around the ankle is increasingly embedded in outpatient treatment concepts. Unfortunately, the classic "ankle block" as a concept of regional anesthesia is inappropriate for surgery around the ankle because the injection sites are too distal to block this specific region.The "high ankle block" avoids this disadvantage by dislocating the injection points 15 cm proximal to the malleoli. Three of five peripheral nerves necessary to perform the block can be reached by a circumferential subcutaneous wall. The Posterior Tibial Nerve and the Deep Peroneal Nerve are addressed by an ultrasound guided approach.The efficacy of the technique is highlighted by a case series (3 cases) in which the new blockade was used as a stand-alone procedure, i.e. without additional general anesthesia.The "high ankle block" may serve as an ultrasound guided expansion to the classic techniques, extending the operative spectrum to the ankle region.
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- 2022
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13. Anatomical and biomechanical evaluation of the lateral calcaneo-cuboid and bifurcate ligaments
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Sebastian F, Baumbach, Manuel, Kistler, Federico P, Gaube, Benjamin, Bartz, Hannes, Traxler, Zach, Throckmorton, Wolfgang, Böcker, and Hans, Polzer
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Foot ,Ligaments, Articular ,Humans ,Orthopedics and Sports Medicine ,Tarsal Bones ,Biomechanical Phenomena - Abstract
This study aims to analyze the ligaments of the dorso-lateral calcaneo-cuboid joint and to assess the biomechanical relevance of the bifurcate ligament.16 specimens were analyzed for their ligamentous anatomy of the dorso-lateral calcaneo-cuboid joint and side-alternating assigned to two groups with varying ligamentous dissection order. The Chopart joint was stressed in plantar, medial, and lateral direction measuring the displacement by an 3D motion tracker for every dissection step.37.5% of specimens had all ligaments (lateral calcaneo-cuboid, dorsal calcaneo-cuboid, bifurcate calcaneo-cuboid, bifurcate calcaneo-navicular), 37.5% were lacking bifurcate´s calcaneo-cuboid-portion, and 25% presented without dorsal calcaneo-cuboid. Biomechanical testing revealed no significant displacement within the calcaneo-cuboid or talo-navicular joint for any stressed state except for axial compression with dissected dorsal talo-navicular joint capsule in Group 2.Broad morphological variability and missing significant displacement regardless of its integrity, make the bifurcate ligament appear of limited biomechanical relevance.
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- 2022
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14. Etablierung von interdisziplinären Extremitätenboards: ein wichtiger Beitrag zur Verbesserung der Versorgung von Patienten mit komplexem Extremitätentrauma
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Arne Hendrik Böcker, Yves Gramlich, Reinhard Hoffmann, Christoph Hirche, Andreas Gather, Paul Alfred Grützner, and Ulrich Kneser
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Orthopedics and Sports Medicine ,Surgery - Published
- 2022
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15. Planar-Biaxial Thermo-mechanical Fatigue Behavior of Nickel-Base Superalloy Inconel 718 Under Proportional Loading
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Marco Böcker, Harish Ramesh Babu, Sebastian Henkel, Mario Raddatz, Uwe Gampe, and Horst Biermann
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Mechanics of Materials ,Metals and Alloys ,Condensed Matter Physics - Abstract
The planar-biaxial thermo-mechanical fatigue behavior of nickel-base superalloy Inconel 718 was studied for selected proportional loading conditions, in particular biaxial strain ratios of 1.0, 0.6, and − 1.0. The cyclic temperature loading with minimum and maximum temperatures of 400 °C and 630 °C and a duration of 250 seconds was either In-Phase or Out-of-Phase to the mechanical axes. Besides the multiaxial tests, uniaxial thermo-mechanical fatigue tests were conducted In-Phase and Out-of-Phase with the same temperature cycle and cycle duration. The performed thermo-mechanical fatigue tests were analyzed regarding the deformation and lifetime behavior and compared with high-temperature isothermal low-cycle fatigue tests from a previous work of the authors. On the side of the lifetime description, a strain- and a stress-based approach were presented. For the planar-biaxial tests, the crack initiation mechanism and crack paths were shown.
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- 2022
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16. Integrative analysis of multimodal mass spectrometry data in MZmine 3
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Robin Schmid, Steffen Heuckeroth, Ansgar Korf, Aleksandr Smirnov, Owen Myers, Thomas S. Dyrlund, Roman Bushuiev, Kevin J. Murray, Nils Hoffmann, Miaoshan Lu, Abinesh Sarvepalli, Zheng Zhang, Markus Fleischauer, Kai Dührkop, Mark Wesner, Shawn J. Hoogstra, Edward Rudt, Olena Mokshyna, Corinna Brungs, Kirill Ponomarov, Lana Mutabdžija, Tito Damiani, Chris J. Pudney, Mark Earll, Patrick O. Helmer, Timothy R. Fallon, Tobias Schulze, Albert Rivas-Ubach, Aivett Bilbao, Henning Richter, Louis-Félix Nothias, Mingxun Wang, Matej Orešič, Jing-Ke Weng, Sebastian Böcker, Astrid Jeibmann, Heiko Hayen, Uwe Karst, Pieter C. Dorrestein, Daniel Petras, Xiuxia Du, and Tomáš Pluskal
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Biomedical Engineering ,Molecular Medicine ,Bioengineering ,Applied Microbiology and Biotechnology ,Biotechnology - Published
- 2023
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17. State of care for EU mobile workers' rights in the Dutch meat sector in times of, and beyond, COVID-19
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Lisa Berntsen, Anita Böcker, Tesseltje De Lange, Sandra Mantu, and Natalia Skowronek
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Sociology and Political Science ,Centre for Migration Law ,General Economics, Econometrics and Finance ,Centrum voor Migratierecht - Abstract
PurposeWith a focus on the position of EU mobile workers in the Dutch meat industry, this article discusses the multi-level State efforts to enhance protection of workers who experienced limited protection of existing State and private enforcement institutions. The COVID-19 pandemic, with virus outbreaks at Dutch meat plants, fuelled public and political will to structurally improve these workers' precarious work and living conditions. Yet, the process of policy change is slow. The authors show it is the gradual transformation in the institutional environment that the State needs to counter to become more protective for EU mobile workers.Design/methodology/approachUsing the gradual institutional change approach and the concept of State ignorance, the authors examine State responses drawing on interviews with expert stakeholders in the public and private domain, public administration records and newspaper articles.FindingsThrough knowledge creation, boosted social dialogue mechanisms, enhanced enforcement capacity and new housing legislation, the Dutch State focuses on countering gradual institutional change through which existing institutions lost their effectiveness as protectors of EU mobile workers. The organization of work is, nevertheless, not (yet) fundamentally addressed with tighter public legislation.Originality/valueThe findings contribute to a more nuanced understanding of the role of the State as multifaceted actor in institutional change processes towards increased protection for EU mobile workers.
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- 2022
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18. Intraoperative alignment correlates well with long standing radiographs - The X-ray grid method in complex knee surgery
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Julian FÜRMETZ, Sven PATZLER, Galina COSOLA, Florian WOLF, Nikolaus DEGEN, Wolf Christian PRALL, Christian EHRNTHALLER, Wolfgang BÖCKER, and Peter Helmut THALLER
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Knee Joint ,Tibia ,X-Rays ,Humans ,Reproducibility of Results ,General Earth and Planetary Sciences ,Osteoarthritis, Knee ,Retrospective Studies ,General Environmental Science - Abstract
While long standing radiographs (LSR) represent the gold standard for preoperative alignment assessment and planning of lower limb deformity corrections, there is no consensus about the intraoperative alignment assesments (IAC) due to various limitations of the common methods. The present study introduces a radiolucent X-ray grid with integrated radiopaque lines explicitly designed for fluoroscopic IAC and evaluates its reliability in comparsion to the LSR.Patients with posttaumatic and congenital lower limb deformity surgery and preoperative LSR as well as fluoroscopic IAC utilizing the X-ray grid were retrospectively included to the study. The mechanical axis deviation (MAD) in percentage of the maximum tibial width from the medial to the lateral in comparison between the image pairs was set as primary outcome parameter. Multiple rater and measurements determined intra- and interobserver reliabilit of both imaging methods. In addition, the effects of age, gender, body mass index (BMI), etiology, joint line convergence angle (JLCA), and extent varus or valgus deformity were analysed.A total of 84 patients were finally included. The mean absolute difference of MAD between the two techniques was 7.2 ± 0.8%. MAD between the LSR and IAC correlated at a high level (R = 0.96, p0.001). The agreement decreased with increasing extent of deformity (p0.01) and with higher deviation of JLCA between LSR and IAC (p0.01). Intra- and interobserver concordance correlation coefficient (CCC) for MAD measurements were 0.99 for both imaging techniques.Fluoroscopy combined with the X-ray grid method is a valid tool for intraoperative assessment of lower limb alignment in deformity correction surgery, and the correlation between LSR and IAC is better than in other similar techniques described in the literature. However, in case of severe coronal alignment deformity and highly divergent JLCA, the agreement between both imaging techniques decreases significantly.
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- 2022
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19. Influence of Plasma Power and Oxygen-Containing Process Gases in Active Screen Plasma Nitrocarburizing with Carbon Solid Source*
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J. Böcker, A. Puth, A. V. Pipa, J.-P. H. van Helden, J. Röpcke, H. Biermann, and A. Dalke
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Materials Chemistry ,Metals and Alloys ,Industrial and Manufacturing Engineering - Abstract
Plasma nitrocarburizing by means of active screen technology using an active screen made of carbon fiber-reinforced carbon was carried out by varying the power at the active screen and using oxygen-containing fresh gas components (O2, CO2) in the N2:H2 plasma using the example of the quenched and tempered steel AISI 4140 (42CrMo4). The investigations focused on the analysis of the process gas by means of laser absorption spectroscopy, the evaluation of the produced compound layers with regard to structure and phase composition, as well as the resulting properties. It was shown that by varying the process gas atmosphere, the structural composition of the compound layer and the concentration profiles of nitrogen and carbon can be specifically influenced. The high concentrations of carbon-containing compounds in the process gas resulted in complete suppression of γ’-Fe4N formation, but cementite was detected in the lower part of the compound layer. The addition of oxygen-containing fresh gases and the resulting change in process gas composition suppressed cementite formation. The results suggest that, in particular, high powers at the carbon active screen and the simultaneous addition of oxygen-containing gases results in the generation of nitrogen-rich, single-phase ε-compound layers.
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- 2022
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20. Biomechanical comparison of screw vs. cerclage refixation in orthogeriatric lesser trochanteric fractures: a cadaveric study
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Christoph, Linhart, Manuel, Kistler, Matthias, Woiczinski, Rouven, Neudeck, Matthias, Kassube, Wolfgang, Böcker, and Christian, Ehrnthaller
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Emergency Medicine ,Orthopedics and Sports Medicine ,Surgery ,Critical Care and Intensive Care Medicine - Abstract
Purpose Osteoporosis-related proximal femur fractures continue to increase significantly due to demographic change. This study was designed to evaluate the biomechanical stability of two different fixation methods (cerclage vs. screw) for refixation of a trochanter minor fragment in the pertrochanteric fractures in cadaveric bones. Methods Artificial bones (n = 14) and human bones (n = 16) were treated with a DHS and the trochanter minor fragment was reduced by cerclage wiring or direct screw fixation. After preloading the simulated iliopsoas with 10 N, a tensile test was performed, ending with either a 70% loss of strength or avulsion of the fragment. The mean values of the avulsion force and the surface strain were recorded. Results All tensile tests showed no significant differences between refixation using a direct screw or wire cerclage, for both artificial bones and human specimens. Absolute values showed higher avulsion forces after direct screw fixation than refixation with a wire cerclage. The surface tension of specimens treated with direct screw fixation was lower than that of specimens treated with wire cerclage. An opposite effect was seen in artificial bones. Both effects were not statistically significant. Conclusion Based on the equal stability after lag screw placement compared to cerclage wiring, we promote the placement of a lag screw into the lesser trochanter fragment in pertrochanteric femur fractures when using a dynamic hip screw. Level of evidence Level III.
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- 2022
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21. High rate of complications after corrective midfoot/subtalar arthrodesis and Achilles tendon lengthening in Charcot arthropathy type Sanders 2 and 3
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Markus Regauer, Veronika Grasegger, Julian Fürmetz, Adrian Calvacanti Kussmaul, Wolfgang Böcker, and Christian Ehrnthaller
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Orthopedics and Sports Medicine ,Surgery - Abstract
Purpose Corrective midfoot resection arthrodesis is the standard treatment of Charcot arthropathy type Sanders 2 and 3 with severe dislocation. In order to critically evaluate the effect of surgical correction, a retrospective analysis of our patient cohort was performed. Hereby, special emphasis was set on the analysis of the pre- and post-operative equinus position of the hindfoot. Methods Retrospectively, all patients (n = 82) after midfoot resection arthrodesis in Charcot type Sanders 2 or 3 were included. Complications were recorded, and the mean complication-free interval was calculated. Additionally, the calcaneal pitch as well as Meary’s angle were measured pre- and post-operatively and in case of complications. Results Overall complication rate was 89%. Revision surgery was necessary in 46% of all patients. The mean complication-free interval was 285 days (0–1560 days). Calcaneal pitch and Meary’s angle significantly improved after operation but returned to pre-operative values after onset of complications. Achilles tendon lengthening showed no significant effects on the mean complication-free interval. Conclusion Operative treatment of Charcot arthropathy remains a surgical challenge with high complication rates. Surgical correction of equinus position has been highlighted for successful treatment but was not able to prevent complications in this study, which is demonstrated by the recurrent decrease of the calcaneal pitch in cases of reoperation. Therefore, as a conclusion of our results, our treatment algorithm changed towards primarily addressing the equinus malpositioning of the hindfoot by corrective arthrodesis of the hindfoot.
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- 2022
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22. Bevindingen en lessen uit de coronacrisis
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Böcker, A.G.M., Lange, T. de, Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290398.pdf (Publisher’s version ) (Open Access)
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- 2023
23. Administratieve (on)zichtbaarheid. De registratie van EU-arbeidsmigranten
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Böcker, A.G.M., Lange, T. de, Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290393.pdf (Publisher’s version ) (Open Access)
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- 2023
24. De arbeidsverhoudingen van EU-arbeidsmigranten
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Böcker, A.G.M., Lange, T. de, Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290394.pdf (Publisher’s version ) (Open Access)
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- 2023
25. Inleiding
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Böcker, A.G.M., Lange, T. de, Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290435.pdf (Publisher’s version ) (Open Access)
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- 2023
26. Huisvesting van EU-arbeidsmigranten in Nederland voor, tijdens en na corona
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Lange, T. de, Böcker, A.G.M., Beckers, P.J., Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Institute for Management Research ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290395.pdf (Publisher’s version ) (Open Access)
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- 2023
27. De coronacrisis, volksgezondheid en de gezondheidsrisico's voor arbeidsmigranten
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Mantu, S.A., Skowronek, N.J., Böcker, A.G.M., Berntsen, L.E., Lange, T. de, Lange, T. de, and Böcker, A.G.M.
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Centre for Migration Law ,Centrum voor Migratierecht - Abstract
Contains fulltext : 290397.pdf (Publisher’s version ) (Open Access)
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- 2023
28. Neue deutschsprachige Arbeiten zur monastischen Architektur des Mittelalters
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Böcker, Hans J.
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Rezension zu: Ernst Badstübner: Klosterkirchen im Mittelalter. Die Baukunst der Reformorden. 2. Aufl. München: C. H. Beck 1985. 290 S. mit 155 Fotos; Günther Binding und Matthias Untermann: Kleine Kunstgeschichte der mittelalterlichen Ordensbaukunst in Deutschland. Darmstadt: Wissenschaftliche Buchgesellschaft 1985. 439 S. mit 542 Strichzeichnungen; Wolfgang Schenkluhn: Ordines Studentes. Aspekte zur Kirchenarchitektur der Dominikaner und Franziskaner im 13. Jahrhundert. Berlin: Gebr. Mann 1985. 249 S. mit 150 Abbildungen., Kunstchronik. Monatsschrift für Kunstwissenschaft, Museumswesen und Denkmalpflege, Bd. 40 Nr. 8 (1987): Kunstchronik. Monatsschrift für Kunstwissenschaft, Museumswesen und Denkmalpflege
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- 2023
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29. The Tolerability and Effectiveness of Marine-Based Ingredients in Cosmetics: A Split-Face Clinical Study of a Serum Spray Containing Fucus vesiculosus Extract, Ulva lactuca Extract, and Ectoin
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Doberenz, Ciska Janssens-Böcker, Karin Wiesweg, and Claudia
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fucoidan ,Ulva lactuca ,ectoin ,split face ,serum spray - Abstract
Introduction: Marine-derived compounds, such as seaweed extracts, fucoidan and ulvans, and ectoin, have gained attention in recent years due to their unique structural and functional characteristics, which make them attractive ingredients for skincare products. In this study, we developed a serum spray based on fucoidan, Ulva lactuca extract, and ectoin and evaluated its efficacy on facial skin. Materials and Methods: A split-face design dermatological evaluation of the serum spray was conducted on 33 subjects with visible signs of skin aging, with 29 subjects completing the study according to its protocol. The subjects had a mean age of 50 years and 16 had sensitive skin. The instrumental efficacy and subjective efficacy of the spray were measured on facial skin by evaluating the trans-epidermal water loss (TEWL), skin pH, skin roughness/wrinkle reduction, and skin hydration at baseline, 20 min after its application and 28 days after its continuous use. Results: We found that the application of the serum spray did not significantly affect the TEWL. The hydration in the area treated with Moisturizer + Spray was 17% higher than that in the area treated with Moisturizer alone after 20 min of application (p < 0.001) and 5% higher after 28 days of use (p < 0.05). Twenty minutes after the application of the product, the average roughness in the area treated with Moisturizer + Spray decreased significantly, with an average of 7% compared to baseline (p < 0.001). With regard to the long-term antiwrinkle effect, 28 days after the continuous use of the product, the average roughness in the area treated with Moisturizer + Spray decreased significantly, with an average of 17% in relation to baseline (p < 0.001). The skin pH was significantly lowered by 6% after 28 days of use of the moisturizer + spray (p < 0.05). Conclusion: The results of this study suggest that the marine-derived compounds fucoidan, ulvans, and ectoin have hydrating and anti-wrinkle properties that make them effective ingredients for skincare products. The serum spray developed in this study was demonstrated to be safe and increase hydration, showing a reduction in wrinkles and maintenance of the skin barrier function after 28 days of its continuous use. Therefore, it could be a promising addition to skincare products for improving skin health.
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- 2023
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30. Curvature of gastrocnemius muscle fascicles as function of muscle-tendon complex length and contraction in humans
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Heieis, Jule, Böcker, Jonas, D'Angelo, Olfa, Mittag, Uwe, Albracht, Kirsten, Schönau, Eckhard, Meyer, Andreas, Voigtmann, Thomas, and Rittweger, Jörn
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fascicle curvature ,ultrasound ,physiology ,muscle fascicles ,biomechanics ,connective tissue - Published
- 2023
31. Lipase-mediated detoxification of host-derived antimicrobial fatty acids byStaphylococcus aureus
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Arnaud Kengmo Tchoupa, Ahmed M. A. Elsherbini, Xiaoqing Fu, Oumayma Ghaneme, Lea Seibert, Marieke A. Böcker, Marco Lebtig, Justine Camus, Stilianos Papadopoulos Lambidis, Birgit Schittek, Dorothee Kretschmer, Michael Lämmerhofer, and Andreas Peschel
- Abstract
Long-chain fatty acids with antimicrobial properties are abundant on the skin and mucosal surfaces, where they are essential to restrict the proliferation of opportunistic pathogens such asStaphylococcus aureus. These antimicrobial fatty acids (AFAs) elicit bacterial adaptation strategies, which have yet to be fully elucidated. Characterizing the pervasive mechanisms used byS. aureusto resist AFAs could open new avenues to prevent pathogen colonization. Here, we identify theS. aureuslipase Lip2 as a novel resistance factor against AFAs. Lip2 detoxifies AFAs via esterification with cholesterol. This is reminiscent of the activity of the fatty acid-modifying enzyme (FAME), whose identity has remained elusive for over three decades.In vitro, Lip2-dependent AFA-detoxification was apparent during planktonic growth and biofilm formation. Our genomic analysis revealed that prophage-mediated inactivation of Lip2 was more common in blood and nose isolates than in skin strains, suggesting a particularly important role of Lip2 for skin colonization. Accordingly, in a mouse model ofS. aureusskin colonization, bacteria were protected from sapienic acid - a human-specific AFA - in a cholesterol- and lipase-dependent manner. These results suggest Lip2 is the long-sought FAME that exquisitely manipulates environmental lipids to promote bacterial growth. Our data support a model in whichS. aureusexploits and/or exacerbates lipid disorders to colonize otherwise inhospitable niches.
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- 2023
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32. The influence of vitamin D on handgrip strength in elderly trauma patients
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Tamara Ostermeier, Leon Faust, Adrian Cavalcanti-Kußmaul, Christian Kammerlander, Matthias Knobe, Wolfgang Böcker, Maximilian M. Saller, Carl Neuerburg, and Alexander M. Keppler
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General Medicine - Abstract
Background and objectives The treatment of elderly patients is an increasing challenge and the long-term sequelae often affect activities of daily living and quality of life in those patients. Handgrip strength (HGS) appears as a promising value to predict the outcome after trauma in elderly patients and to assess the overall muscle strength. Besides the possible role of psychological and hormonal factors, vitamin D may have a positive influence. Furthermore, some data suggest that Vitamin D is beneficial regarding muscle strength and possibly prevents further falls and injuries in orthogeriatric patients. The purpose of this study was to identify if Vitamin D is an influencing factor for HGSin elderly trauma patients. Materials and methods 94 elderly patients in a Level I Trauma Center aged 60 years or older were prospectively enrolled and HGS as well as serum 25-OH Vitamin D concentration (VDC) were measured. In addition, the standardized questionnaires Barthel Index (BI), Parker Mobility Score (PMS), Short Physical Performance Battery (SPPB), Strength, Assistance with walking, Rise from a chair, Climb stairs and Falls (SARC-F) and European Quality of Life 5 Dimensions 5 Levels Questionnaire (EQ-5D-5L), were used to record mental health status and demographic data. Results HGS is mainly related to age and sex in elderly trauma patients. HGS was higher in men (meanmale = 27.31 kg (± 8.11), meanfemale = 15.62 kg (± 5.63), p age = − 0.58, p VDC = − 0.27, pVDC VDC VDC anxiety+depression = − 0.26, panxiety+depression Conclusions These results do not support the hypothesis that Vitamin D has a positive influence on muscle strength measured by HGS. Nevertheless, this study could confirm the usefulness of HGS as a tool to detect the risk for frequent falls or stumbling. Furthermore, HGS seems to be associated with dizziness and age at onset of menopause. A significant decrease of HGS could also be shown in patients with anxiety and depression. This underlines the importance of interdisciplinary treatment of elderly trauma patients and needs to be taken into account for further studies, as especially the psychological motivation seems to have a significant influence and is sometimes not considered enough in elderly musculo-skeletal patients.
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- 2023
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33. Associations between long-term exercise participation and lower limb joint and whole-bone geometry in young and older adults
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Scorcelletti, Matteo, Zange, Jochen, Böcker, Jonas, Sies, Wolfram, Lau, Patrick, Mittag, Uwe, Reeves, Neil D, Ireland, Alex, and Rittweger, Jörn
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femur shape ,hip shape ,master athletes ,Physiology ,Physiology (medical) ,skeletal development ,tibia - Abstract
Introduction: Features of lower limb bone geometry are associated with movement kinematics and clinical outcomes including fractures and osteoarthritis. Therefore, it is important to identify their determinants. Lower limb geometry changes dramatically during development, partly due to adaptation to the forces experienced during physical activity. However, the effects of adulthood physical activity on lower limb geometry, and subsequent associations with muscle function are relatively unexplored.Methods: 43 adult males were recruited; 10 young (20–35 years) trained i.e., regional to world-class athletes, 12 young sedentary, 10 older (60–75 years) trained and 11 older sedentary. Skeletal hip and lower limb geometry including acetabular coverage and version angle, total and regional femoral torsion, femoral and tibial lateral and frontal bowing, and frontal plane lower limb alignment were assessed using magnetic resonance imaging. Muscle function was assessed recording peak power and force of jumping and hopping using mechanography. Associations between age, training status and geometry were assessed using multiple linear regression, whilst associations between geometry and muscle function were assessed by linear mixed effects models with adjustment for age and training.Results: Trained individuals had 2° (95% CI:0.6°–3.8°; p = 0.009) higher femoral frontal bowing and older individuals had 2.2° (95% CI:0.8°–3.7°; p = 0.005) greater lateral bowing. An age-by-training interaction indicated 4° (95% CI:1.4°–7.1°; p = 0.005) greater acetabular version angle in younger trained individuals only. Lower limb geometry was not associated with muscle function (p > 0.05).Discussion: The ability to alter skeletal geometry via exercise in adulthood appears limited, especially in epiphyseal regions. Furthermore, lower limb geometry does not appear to be associated with muscle function.
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- 2023
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34. Tape suture constructs for instabilities of the pubic symphysis: is the idea of motion preservation a suitable treatment option? A cadaver study
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Adrian Cavalcanti Kußmaul, Fanny Schwaabe, Manuel Kistler, Maximilian Jörgens, Korbinian F. Schreyer, Axel Greiner, Wolfgang Böcker, and Christopher A. Becker
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Orthopedics and Sports Medicine ,Surgery ,General Medicine - Abstract
Introduction Current gold standard for the treatment of symphyseal disruptions includes anterior plating, almost entirely prohibiting symphyseal mobility and resulting in an iatrogenic arthrodesis followed by high rates of implant failure. Minimally invasive tape suture constructs have been found to maintain the micro mobility of ligamentous injuries, yet still providing sufficient biomechanical stability. Recently, this technique has been primarily investigated for symphyseal disruptions on synthetic pelvic models. Therefore, the aim of this study was to examine the feasibility of this novel flexible osteosynthesis on cadaveric pelvic models based on the following hypothesis: tape suture constructs ensure sufficient biomechanical stability without inhibiting micro mobility of the pubic symphysis for the treatment of symphyseal disruptions and maintain stability during long-term loading. Materials and methods 9 cadaveric anterior pelvic rings were used in this study and a symphyseal disruption was created in every specimen. The specimens were then exposed to short- and long-term vertical and horizontal cyclic loading after treatment with a tape suture construct in criss-cross technique. The mean maximum displacement (mm) during cyclic loading and the corresponding stiffness (N/mm) were measured and compared. Results Regarding both displacement (mm) and corresponding stiffness (N/mm), the tape sutures displayed a significant difference between short- and long-term loading for cranial and caudal vertical loading (p p > 0.05). No tape suture suffered from implant failure during long-term loading. Conclusions The tape suture construct displayed sufficient biomechanical stability without exceeding the physiological mobility of 2 mm of the pubic symphysis; however, also maintained the desired micro mobility of the affected joint necessary to prevent an iatrogenic arthrodesis. Further, all tape sutures maintained stability throughout long-term loading.
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- 2022
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35. Differentialtherapeutische Herangehensweisen zur Behandlung des Karpaltunnelsyndroms
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Leila Harhaus, Simeon C. Daeschler, Martin Aman, Arne Hendrik Böcker, Felix Klimitz, and Berthold Bickert
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Orthopedics and Sports Medicine ,Surgery - Abstract
ZusammenfassungDas Karpaltunnelsyndrom (KTS) stellt die häufigste kompressionsbedingte Neuropathie dar. Die Therapieführung ist patientenindividuell zu gestalten. Die initiale konservative Therapie hat insbesondere im Anfangsstadium einen hohen Stellenwert. Die Indikation zur primären chirurgischen Therapie besteht bei therapierefraktären Situationen, ab mittelschweren Stadien oder bei Vorliegen relevanter Begleiterkrankungen (Raumforderungen, komplex regionalem Schmerzsyndrom, diabetische Polyneuropathie) und zunehmend auch beim KTS in der Schwangerschaft. Die unterschiedlichen Operationstechniken, deren differentialtherapeutische Anwendung, sowie deren Vor- und Nachteile sollen in dieser Arbeit pragmatisch dargestellt werden. Auch die herausfordernden Rezidivsituationen und -eingriffe werden hierbei herausgehoben. Vor dem Hintergrund der neu erschienenen aktualisierten S3-Leitlinie „Diagnostik- und Therapie des Karpaltunnelsyndroms“ hat dieser Themenbereich eine aktuelle Relevanz.
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- 2022
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36. Correlation between EFAS- and MOCART score and clinical outcome after AMIC®-procedure for osteochondral lesion of the talus
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Oliver Gottschalk, Judith Mazet, Florian Kerschl, Hedwig Schenk, Eduardo M. Suero, Hubert Hörterer, Wolfgang Böcker, and Markus Walther
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Orthopedics and Sports Medicine ,Surgery ,General Medicine - Published
- 2022
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37. Akuttherapie und Remissionserhalt des M. Crohn
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J.C. Preiß and U. Böcker
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Gastroenterology - Published
- 2022
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38. Pain levels during distraction osteogenesis with lengthening nails in 168 cases
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Nikolaus Degen, N. de Almeida Lopes, F. Wolf, J. Fürmetz, E. Euler, W. Böcker, and P. H. Thaller
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Orthopedics and Sports Medicine ,Surgery - Abstract
Purpose To firstly examine the pain levels during distraction osteogenesis (DO) with lengthening nails (LN) in a large sample. Methods A total of 168 cases underwent DO of the tibia or femur with five different models of LN. Under a standardized medical regime, daily pain levels were noted as nominal rating scale (NRS) score (0–10) during the distraction phase. NRS scores and several potential influence factors (LN model, bone, approach, side, age, gender) were evaluated. Results The mean distraction length was 39.1 ± 14.4 mm. The average NRS score decreased from postoperative day 1 with 2.84 nonlinearly by 1.03 points (36.3%) over the course of 62 days to an average score of 1.81. The mean decrease during the first thirty days was 0.67(23.6%). Subgroup analysis did not reveal any influence factors. Conclusion Pain levels during the distraction phase are overall low, continuously decreasing, and well manageable with mostly non-opioid analgesics.
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- 2022
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39. Osteoporose: Diagnostik und Behandlung
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Ulla Stumpf, Moritz Kraus, Roland Ladurner, Carl Neuerburg, and Wolfgang Böcker
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- 2022
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40. Does augmentation increase the pull-out force of symphyseal screws? A biomechanical cadaver study
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Adrian Cavalcanti Kußmaul, Fanny Schwaabe, Christopher Alexander Becker, Christian Kleber, Christoph Linhart, Christoph Thorwächter, Bianka Rubenbauer, Wolfgang Böcker, and Axel Greiner
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Fracture Fixation, Internal ,Bone Screws ,Bone Cements ,Cadaver ,Emergency Medicine ,Humans ,Orthopedics and Sports Medicine ,Surgery ,Critical Care and Intensive Care Medicine ,Biomechanical Phenomena - Abstract
Purpose Open reduction and internal fixation using anterior plate osteosynthesis currently represents the gold standard for the treatment of symphyseal disruptions. Since postoperative screw loosening with consequent implant failure is frequently observed, this study aims to evaluate if and to what extent augmentation can increase the pull-out force of symphyseal screws to improve the constructs stability. Methods Twelve human cadaveric anterior pelvic rings were separated at the symphyseal joint for bilateral testing, consequently achieving comparable sites. First, one non-augmented screw was drilled into the superior pubic ramus, whereas the contralateral side was primarily augmented. The screws were then withdrawn with a constant speed of 10 mm/min and the fixation strengths determined by the force (N) displacement (mm) curve. Finally, the primary non-augmented site was secondary augmented, representing revision surgery after initial implant failure, and the corresponding fixation strength was measured again. Results Augmentation compared to non-augmented screws displayed significantly higher pull-out forces with an increase in pull-out force by 377% for primary and 353% for secondary augmentation (p p = 0.74). Conclusions Primary and secondary augmentation significantly increases the stability of symphyseal screws and, therefore, potentially decreases rates of implant failure.
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- 2022
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41. Transverse Kallusdistraktion
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P. H. Thaller, J Fürmetz, W Böcker, and C Ehrnthaller
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Emergency Medicine ,Orthopedics and Sports Medicine ,Surgery - Published
- 2022
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42. Planar‐biaxial low‐cycle fatigue behavior of the nickel‐base alloy Inconel 718 at elevated temperatures under selected loading conditions
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Marco Böcker, Harish Ramesh Babu, Sebastian Henkel, Mario Raddatz, Uwe Gampe, and Horst Biermann
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2022
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43. Der Wandel der Anerkennung von Fehl- und Totgeburt als Geburt eines Kindes
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Julia Böcker
- Subjects
General Social Sciences - Abstract
ZusammenfassungDas Aufkommen der Alternativbezeichnungen „Kleine Geburt“ und „Stille Geburt“ ist Ausdruck eines Wandels im Umgang mit Fehlgeburt und Totgeburt. Anstoß des Wandels war zivilgesellschaftliches Engagement Betroffener in den 1980er-Jahren, die sich gegen Entrechtungen in den Kliniken und für soziale Sichtbarkeit und Anerkennung des Verlusts einsetzten. Im Beitrag wird argumentiert, dass Fehl- und Totgeburt in Gesellschaft und Geburtshilfe zunehmend als Geburt (und Verlust) eines Kindes behandelt und Betroffene damit als Eltern anerkannt werden. Empirische Grundlage ist ein Datenkorpus aus narrativen Interviews und natürlichen Daten, die sequenzanalytisch und theoriegenerierend ausgewertet wurden. Der mehrdimensionale Wandel wird anhand von Veränderungen im deutschen Recht, in sozialen Medien und in der Geburtshilfe plausibilisiert. Erstens werden Betroffene durch Änderungen des Personenstandsgesetzes für Fehlgeborene symbolisch als Eltern anerkannt. Zweitens entwickelte sich in Online-Foren ein kollektives Selbstverständnis von „Sternenelternschaft“, das diskursive und institutionelle Veränderungen außerhalb des Internets bewirkte. Daneben legitimieren und normalisieren individuelle Selbstzeugnisse in den sozialen Medien, über Fehl- und Stillgeburt zu sprechen und diese zu zeigen. Drittens werden die professionellen Praktiken der Personalisierung von Stillgeborenen in der Geburtshilfe diskutiert, die nach Totgeburten inzwischen umfänglich, nach Fehlgeburten teilweise, etabliert sind.
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- 2022
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44. Anforderungen für den 3-D-Druck von Implantaten
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Titus Kuehlein, Sebastian Andress, Adrian Cavalcanti Kußmaul, Christopher A. Becker, Christoph Linhart, Wolfgang Böcker, and Simon Weidert
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General Medicine - Abstract
Zusammenfassung3-D-Druck wird in der Unfallchirurgie und Orthopädie zunehmend für die Herstellung patientenspezifischer Implantate verwendet. Ziel dieses strukturierten Reviews ist es, aktuelle Merkmale und Fähigkeiten zu ermitteln und hieraus Anforderungen an das Implantatdesign und den -druck abzuleiten. Hierzu wurden 98 Veröffentlichungen der letzten 5 Jahre analysiert.Neben Kunststoffen und Metallen können auch biologisches Material und Medikamentensuspensionen zum Druck verwendet werden. Der 3-D-Druck bietet den Vorteil, dass die Implantate individuell an die Anatomie und Pathologie des Patienten angepasst werden können, also auch bewusst Einfluss auf biomechanischen und -mimetischen Eigenschaften genommen werden kann. Beispielsweise kann die Oberfläche der Implantate gezielt so optimiert werden, dass eine Osteoinduktivität bewirkt wird. Angewandt wird das Verfahren zum Gelenk- und Knochenersatz sowie für Knorpel- und Weichteilrekonstruktionen.Somit ergeben sich diverse Anforderungen an das Design und die Herstellung. Da es sich um ein sehr zeit- und kostenintensives Verfahren handelt, sollte eine klare Überlegenheit zu herkömmlichen Behandlungsmethoden bestehen. Aufgrund der Komplexität des Prozesses ist eine Qualitätssicherung unabdingbar, um die Sicherheit des Patienten zu gewährleisten.Bei komplexen oder von der Norm abweichenden Fällen wird der 3-D-Druck sich zunehmend durchsetzen. Um Qualität zu gewährleisten und effiziente Prozesse zu etablieren, ist eine engere Verzahnung zwischen Behandlern und Herstellern unabdingbar.
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- 2022
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45. System for Continuous Multi-Dimensional Mobile Network KPI Tracking and Prediction in Drifting Environments
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Hendrik Schippers, Stefan Böcker, and Christian Wietfeld
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- 2023
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46. Time-Optimal Model Predictive Control of Permanent Magnet Synchronous Motors in the Whole Speed and Modulation Range Considering Current and Torque Constraints
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Joachim Böcker, Oliver Wallscheid, and Anian Brosch
- Abstract
Improving control dynamics and enabling maximum torque and power conversion for a given electrical drive are important target quantities of drive control algorithms. To utilize the electrical drive to its maximum extent during transient and steady-state operation, a time-optimal continuous-control-set model predictive flux control (CCS-MPFC) for permanent magnet synchronous motors (PMSM) is proposed. This scheme considers torque and current limits as softened state constraints in the CCS-MPFC’s optimization problem to prevent transient overcurrents as well as torque over- and undershoots during time-optimal operating point changes. Furthermore, the overmodulation range including six-step operation can be entered seamlessly to ensure maximum power conversion at high speeds. Fastest transients within the whole modulation range are enabled by a time-optimal harmonic reference generator (TO-HRG). Here, the flux reference of the CCS-MPFC is complemented with a harmonic content that enables operation in the overmodulation region. Further, the reference is pre-rotated during transient operation to attain time-optimal control performance. Extensive simulative as well as experimental investigations for linearly and nonlinearly magnetized PMSMs show that, compared to state-of-the-art methods, time-optimal control performance in the whole modulation range without transient overcurrents as well as torque over- and undershoots can be achieved by the proposed control method.
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- 2023
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47. Intelligente Lernunterstützung
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Yves Gensterblum, Jessica Böcker, and wbv Media Repository
- Subjects
Intelligente Lernunterstützung ,Vereinbarkeit eines Weiterbildungsprogramms mit beruflichen und privaten Verpflichtungen ,chronischem Zeitmangel - Abstract
Die Zielgruppe der beruflichen Weiterbildung leidet oft unter chronischem Zeitmangel. Daher gilt die Vereinbarkeit eines Weiterbildungsprogramms mit beruflichen und privaten Verpflichtungen als ein bedeutsames Qualitätskriterium. Im BMBF-geförderten Projekt »Willen - Weiterbildung mit intelligenter Lernunterstützung ist effizient und nachhaltig« werden Lernprozesse der Teilnehmenden im Zertifikatskurs »Six Sigma Green Belt - hybrid« an der Akademie der Ruhr-Universität Bochum, in dem Prozess- und Qualitätsmanagementinhalte vermittelt werden, durch ein hybrides Kurskonzept und den Einsatz eines adaptiven Curriculums im Hinblick auf Lerneffizienz und -effektivität so optimiert, dass die Lerndauer insgesamt verkürzt werden kann.
- Published
- 2023
48. It Is Always the Same—A Complication Classification following Angular Stable Plating of Proximal Humeral Fractures
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Georg Siebenbürger, Rouven Neudeck, Mark Philipp Daferner, Evi Fleischhacker, Wolfgang Böcker, Ben Ockert, and Tobias Helfen
- Subjects
proximal humeral fracture ,complications ,complication classification ,angular stable plating locking plate osteosynthesis ,mid-term ,functional outcome ,constant score ,General Medicine - Abstract
Introduction: The aim of this study was to create a novel complication classification for osteosynthesis-related complications following angular stable plating of the proximal humerus subsuming the influence of these complications on clinical outcome in relation to fracture morphology and consequent revision strategies. A total of 1047 proximal humerus fractures with overall 193 osteosynthesis-associated complications (24.5%) were included. The following complication types could be clarified: complication Type 1 is defined by mild varus (20°) of the humeral head with screw cutout at the humeral head cortex. Complication Type 3 describes a displacement of the angular stable plate in the humeral shaft region with associated shaft-sided screw cutout, while the position of the humeral head remains static. Complication Type 4 is characterized by the occurrence of AVN with or without glenoidal affection (4a/b). Clinical outcome according to the constant score was mainly affected by type 2–4, leading to a deteriorated result. Depending on the type of complication, specific revision strategies can be considered. Additionally, more complex fracture patterns fostered the incidence of complications.
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- 2023
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49. Group Intervention for Goal-Directed Ecological Engagement: Initial Manuscript
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Benedikt T. Seger and Noemi Böcker
- Abstract
With the present intervention, we seek to promote individual ecological engagement aimed at reducing one’s negative environmental impact (ecological footprint) or increasing one’s positive impact on societal transformation (ecological handprint). We examined whether a workshop applying goal concretization and action planning techniques to a group setting helps participants achieve their goals and advance in the process of self-regulated behavior change (Bamberg, 2013). Additionally, we investigated the role of social-cognitive and emotional predecessors of ecological engagement based on reasoned action, norm activation, and social identity approaches.Thirty-five people participated each in one of four two-hour workshops, forming an early (experimental) and a late intervention (waiting) group. Three measurements took place, one before the workshops, one between the early and late workshops, and one after the workshops.As expected, goal achievement and implementation intention (i.e., the transition to the most advanced stage of self-regulated behavior change) increased following the workshop, with implementation intention predicting goal achievement. Social norms referring to the workshop group, personal norms, and anger were significant predictors of earlier stage transitions of behavior change (i.e., goal intention and behavioral intention).There is preliminary evidence that this intervention helps individuals achieve their ecological engagement goals by supporting processes of self-regulated behavior change.
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- 2023
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50. Small molecule machine learning: All models are wrong, some may not even be useful
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Fleming Kretschmer, Jan Seipp, Marcus Ludwig, Gunnar W. Klau, and Sebastian Böcker
- Abstract
A central assumption of all machine learning is that the training data are an informative subset of the true distribution we want to learn. Yet, this assumption may be violated in practice. Recently, learning from the molecular structures of small molecules has moved into the focus of the machine learning community. Usually, those small molecules are of biological interest, such as metabolites or drugs. Applications include prediction of toxicity, ligand binding or retention time.We investigate how well certain large-scale datasets cover the space of all known biomolecular structures. Investigation of coverage requires a sensible distance measure between molecular structures. We use a well-known distance measure based on solving the Maximum Common Edge Subgraph (MCES) problem, which agrees well with the chemical and biochemical intuition of similarity between compounds. Unfortunately, this computational problem is NP-hard, severely restricting the use of the corresponding distance measure in large-scale studies. We introduce an exact approach that combines Integer Linear Programming and intricate heuristic bounds to ensure efficient computations and dependable results.We find that several large-scale datasets frequently used in this domain of machine learning are far from a uniform coverage of known biomolecular structures. This severely confines the predictive power of models trained on this data. Next, we propose two further approaches to check if a training dataset differs substantially from the distribution of known biomolecular structures. On the positive side, our methods may allow creators of large-scale datasets to identify regions in molecular structure space where it is advisable to provide additional training data.
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- 2023
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