TY - JOUR A1 - Ketelhut, Maike A1 - Göll, Fabian A1 - Braunstein, Björn A1 - Albracht, Kirsten A1 - Abel, Dirk T1 - Comparison of different training algorithms for the leg extension training with an industrial robot JF - Current Directions in Biomedical Engineering N2 - In the past, different training scenarios have been developed and implemented on robotic research platforms, but no systematic analysis and comparison have been done so far. This paper deals with the comparison of an isokinematic (motion with constant velocity) and an isotonic (motion against constant weight) training algorithm. Both algorithms are designed for a robotic research platform consisting of a 3D force plate and a high payload industrial robot, which allows leg extension training with arbitrary six-dimensional motion trajectories. In the isokinematic as well as the isotonic training algorithm, individual paths are defined i n C artesian s pace by sufficient s upport p oses. I n t he i sotonic t raining s cenario, the trajectory is adapted to the measured force as the robot should only move along the trajectory as long as the force applied by the user exceeds a minimum threshold. In the isotonic training scenario however, the robot’s acceleration is a function of the force applied by the user. To validate these findings, a simulative experiment with a simple linear trajectory is performed. For this purpose, the same force path is applied in both training scenarios. The results illustrate that the algorithms differ in the force dependent trajectory adaption. KW - Rehabilitation Technology and Prosthetics KW - Surgical Navigation and Robotics Y1 - 2018 U6 - https://doi.org/10.1515/cdbme-2018-0005 SN - 2364-5504 VL - 4 IS - 1 SP - 17 EP - 20 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Stäudle, Benjamin A1 - Seynnes, Olivier A1 - Laps, Guido A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Altered gastrocnemius contractile behavior in former achilles tendon rupture patients during walking JF - Frontiers in Physiology N2 - Achilles tendon rupture (ATR) remains associated with functional limitations years after injury. Architectural remodeling of the gastrocnemius medialis (GM) muscle is typically observed in the affected leg and may compensate force deficits caused by a longer tendon. Yet patients seem to retain functional limitations during—low-force—walking gait. To explore the potential limits imposed by the remodeled GM muscle-tendon unit (MTU) on walking gait, we examined the contractile behavior of muscle fascicles during the stance phase. In a cross-sectional design, we studied nine former patients (males; age: 45 ± 9 years; height: 180 ± 7 cm; weight: 83 ± 6 kg) with a history of complete unilateral ATR, approximately 4 years post-surgery. Using ultrasonography, GM tendon morphology, muscle architecture at rest, and fascicular behavior were assessed during walking at 1.5 m⋅s–1 on a treadmill. Walking patterns were recorded with a motion capture system. The unaffected leg served as control. Lower limbs kinematics were largely similar between legs during walking. Typical features of ATR-related MTU remodeling were observed during the stance sub-phases corresponding to series elastic element (SEE) lengthening (energy storage) and SEE shortening (energy release), with shorter GM fascicles (36 and 36%, respectively) and greater pennation angles (8° and 12°, respectively). However, relative to the optimal fascicle length for force production, fascicles operated at comparable length in both legs. Similarly, when expressed relative to optimal fascicle length, fascicle contraction velocity was not different between sides, except at the time-point of peak series elastic element (SEE) length, where it was 39 ± 49% lower in the affected leg. Concomitantly, fascicles rotation during contraction was greater in the affected leg during the whole stance-phase, and architectural gear ratios (AGR) was larger during SEE lengthening. Under the present testing conditions, former ATR patients had recovered a relatively symmetrical walking gait pattern. Differences in seen AGR seem to accommodate the profound changes in MTU architecture, limiting the required fascicle shortening velocity. Overall, the contractile behavior of the GM fascicles does not restrict length- or velocity-dependent force potentials during this locomotor task. KW - tendon rupture KW - muscle fascicle behavior KW - walking gait KW - force generation KW - ultrasound imaging Y1 - 2022 U6 - https://doi.org/10.3389/fphys.2022.792576 SN - 1664-042X VL - 13 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Quittmann, Oliver J. A1 - Abel, Thomas A1 - Albracht, Kirsten A1 - Strüder, Heiko K. T1 - Biomechanics of all-out handcycling exercise: kinetics, kinematics and muscular activity of a 15-s sprint test in able-bodied participants JF - Sports Biomechanics N2 - This study aims to quantify the kinematics, kinetics and muscular activity of all-out handcycling exercise and examine their alterations during the course of a 15-s sprint test. Twelve able-bodied competitive triathletes performed a 15-s all-out sprint test in a recumbent racing handcycle that was attached to an ergometer. During the sprint test, tangential crank kinetics, 3D joint kinematics and muscular activity of 10 muscles of the upper extremity and trunk were examined using a power metre, motion capturing and surface electromyography (sEMG), respectively. Parameters were compared between revolution one (R1), revolution two (R2), the average of revolution 3 to 13 (R3) and the average of the remaining revolutions (R4). Shoulder abduction and internal-rotation increased, whereas maximal shoulder retroversion decreased during the sprint. Except for the wrist angles, angular velocity increased for every joint of the upper extremity. Several muscles demonstrated an increase in muscular activation, an earlier onset of muscular activation in crank cycle and an increased range of activation. During the course of a 15-s all-out sprint test in handcycling, the shoulder muscles and the muscles associated to the push phase demonstrate indications for short-duration fatigue. These findings are helpful to prevent injuries and improve performance in all-out handcycling. KW - Handbike KW - sEMG KW - Paralympic sport KW - performance testing KW - high-intensity exercise Y1 - 2022 U6 - https://doi.org/10.1080/14763141.2020.1745266 SN - 1752-6116 (Onlineausgabe) SN - 1476-3141 (Druckausgabe) VL - 21 IS - 10 SP - 1200 EP - 1223 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Werkhausen, Amelie A1 - Willwacher, Steffen A1 - Albracht, Kirsten T1 - Medial gastrocnemius muscle fascicles shorten throughout stance during sprint acceleration JF - Scandinavian Journal of Medicine & Science in Sports N2 - The compliant nature of distal limb muscle-tendon units is traditionally considered suboptimal in explosive movements when positive joint work is required. However, during accelerative running, ankle joint net mechanical work is positive. Therefore, this study aims to investigate how plantar flexor muscle-tendon behavior is modulated during fast accelerations. Eleven female sprinters performed maximum sprint accelerations from starting blocks, while gastrocnemius muscle fascicle lengths were estimated using ultrasonography. We combined motion analysis and ground reaction force measurements to assess lower limb joint kinematics and kinetics, and to estimate gastrocnemius muscle-tendon unit length during the first two acceleration steps. Outcome variables were resampled to the stance phase and averaged across three to five trials. Relevant scalars were extracted and analyzed using one-sample and two-sample t-tests, and vector trajectories were compared using statistical parametric mapping. We found that an uncoupling of muscle fascicle behavior from muscle-tendon unit behavior is effectively used to produce net positive mechanical work at the joint during maximum sprint acceleration. Muscle fascicles shortened throughout the first and second steps, while shortening occurred earlier during the first step, where negative joint work was lower compared with the second step. Elastic strain energy may be stored during dorsiflexion after touchdown since fascicles did not lengthen at the same time to dissipate energy. Thus, net positive work generation is accommodated by the reuse of elastic strain energy along with positive gastrocnemius fascicle work. Our results show a mechanism of how muscles with high in-series compliance can contribute to net positive joint work. KW - locomotion KW - muscle mechanics KW - running KW - sprint start KW - ultrasonography Y1 - 2021 U6 - https://doi.org/10.1111/sms.13956 SN - 0905-7188 (Druckausgabe) SN - 1600-0838 (Onlineausgabe) VL - 31 IS - 7 SP - 1471 EP - 1480 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Monti, Elena A1 - Waldvogel, Janice A1 - Ritzmann, Ramona A1 - Freyler, Kathrin A1 - Albracht, Kirsten A1 - Helm, Michael A1 - De Cesare, Niccolò A1 - Pavan, Piero A1 - Reggiani, Carlo A1 - Gollhofer, Albert A1 - Narici, Marco Vincenzo T1 - Muscle in variable gravity: “I do not know where I am, but I know what to do” JF - Frontiers in Physiology N2 - Performing tasks, such as running and jumping, requires activation of the agonist and antagonist muscles before (motor unit pre-activation) and during movement performance (Santello and Mcdonagh, 1998). A well-timed and regulated muscle activation elicits a stretch-shortening cycle (SSC) response, naturally occurring in bouncing movements (Ishikawa and Komi, 2004; Taube et al., 2012). By definition, the SSC describes the stretching of a pre-activated muscle-tendon complex immediately followed by a muscle shortening in the concentric push-off phase (Komi, 1984). Given the importance of SSC actions for human movement, it is not surprising that many studies investigated the biomechanics of this phenomenon; in particular, drop jumps (DJs) represent a good paradigm to study muscle fascicle and tendon behavior in ballistic movements involving the SSC. Within a DJ, three main phases [pre-activation, braking, and push-off (PO; Komi, 2000)] have been recognized and extensively studied in common and challenging conditions, such as changes in load, falling height, or simulated hypo-gravity (Avela et al., 1994; Arampatzis et al., 2001; Fukashiro et al., 2005; Ishikawa et al., 2005; Sousa et al., 2007; Ritzmann et al., 2016; Helm et al., 2020). These studies show that the timing and amount of triceps-surae muscle-tendon unit pre-activation in DJs are differentially regulated based on the load applied to the muscle, being optimal in normal “Earth” gravity conditions (Avela et al., 1994), but decreased in simulated hypo-gravity, hyper-gravity (Avela et al., 1994; Ritzmann et al., 2016), or unknown conditions (i.e., unknown falling heights; Helm et al., 2020). Some authors indicated that, when falling from heights different from the optimal one [defined as the drop height giving a maximum DJ performance indicated as peak ground reaction force (GRF) or jump high], electromyographic (EMG) activity of the plantar flexors increases from lower than optimal to higher than optimal heights (Ishikawa and Komi, 2004; Sousa et al., 2007). These findings highlight the ability of the central nervous system to regulate the timing and amount of pre-activation according to different jumping conditions, thus regulating muscle fascicle length, tendon and joint stiffness as well as position, in order to safely land on the ground and quickly re-bounce. Similarly, to pre-activation, also in the braking phase, the plantar flexors are differentially regulated. In optimal height (i.e., load) jumping conditions, gastrocnemius medialis (GM) fascicles shorten at early ground contact (possibly due to the intervention of the stretch reflex; Gollhofer et al., 1992) and behave quasi-isometrically in the late braking phase, enabling tendon elongation, and storage of elastic energy (Gollhofer et al., 1992; Fukashiro et al., 2005; Sousa et al., 2007). When increasing the falling height (augmenting the impact GRF), the quasi-isometric behavior of fascicles disappears, and fast fascicle lengthening occurs (Ishikawa et al., 2005; Sousa et al., 2007). In the third and last PO phase, fascicles shorten and the tendon releases the elastic energy previously stored. Bobbert et al. (1987) reported no influence of jumping height on the work done and on the net vertical impulse assessed during PO; this observation suggests that, despite an optimal DJ performance might be achieved only in specific conditions (falling heights, loads), the central nervous system seems to be able to regulate muscle behavior in order to effectively perform the required task also in challenging situations. Although the regulation of triceps-surae muscle-tendon unit in DJs has been extensively investigated, very few studies focused on sarcomeres behavior during the performance of this SSC movement (Kurokawa et al., 2003; Fukashiro et al., 2005, 2006). Sarcomeres represent muscle contractile units and are known to express different amounts of force depending on their length (Gordon et al., 1966; Walker and Schrodt, 1974); thus, understanding the time course of their responses during DJs is fundamental to gain further insights into muscle force-generating capacity. In vivo measurement of sarcomere length in humans has been so far been performed only in static positions and under highly controlled experimental conditions (Llewellyn et al., 2008; Sanchez et al., 2015). Instead, human sarcomere length estimation (achieved by dividing GM measured fascicle length for a fixed sarcomere number) in dynamic contractions provided an indirect measure of sarcomere operating range during squat jump, countermovement jump, and DJ (Fukashiro et al., 2005, 2006; Kurokawa et al., 2003). The results of these studies showed that sarcomeres operate in the ascending limb of their length-tension (L-T) relationship in all types of jumps, and particularly so in DJ. However, most of the available observations on sarcomere and muscle fascicle behavior were made in condition of constant gravity. Thus, in order to understand how sarcomere and muscle fascicle length are regulated in variable gravity conditions, we performed experiments in a parabolic flight, involving variable gravity levels, ranging from about zero-g to about double the Earth’s gravity (1 g; Waldvogel et al., 2021). Specifically, the aims of the present study were as follows: 1. To investigate the ability of the neuromuscular system in regulating fascicle length in response to conditions of variable gravity. 2. To estimate sarcomere operative length in the different DJ phases, in order to calculate its theoretical force production and its possible modulation in conditions of variable gravity. We hypothesized that muscle fascicles would be differentially regulated in different gravity conditions compared to 1 g, particularly in anticipation of landing and re-bouncing in unknown gravity levels. In addition, we hypothesized that sarcomeres would operate in the upper part of the ascending limb of their L-T relationship, possibly lengthening during the braking phase (especially in hyper-gravity) while operating quasi-isometrically in 1 g. KW - parabolic flight KW - drop jump KW - hypo-gravity KW - hyper-gravity KW - sarcomere operating length Y1 - 2021 U6 - https://doi.org/10.3389/fphys.2021.714655 SN - 1664-042X VL - 12 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Stäudle, Benjamin A1 - Seynnes, Olivier A1 - Laps, Guido A1 - Göll, Fabian A1 - Brüggemann, Gert-Peter A1 - Albracht, Kirsten T1 - Recovery from achilles tendon repair: a combination of Postsurgery Outcomes and Insufficient remodeling of muscle and tendon JF - Medicine & Science in Sports & Exercise N2 - Achilles tendon rupture (ATR) patients have persistent functional deficits in the triceps surae muscle–tendon unit (MTU). The complex remodeling of the MTU accompanying these deficits remains poorly understood. The purpose of the present study was to associate in vivo and in silico data to investigate the relations between changes inMTU properties and strength deficits inATR patients. Methods: Elevenmale subjects who had undergone surgical repair of complete unilateral ATR were examined 4.6 ± 2.0 (mean ± SD) yr after rupture. Gastrocnemius medialis (GM) tendon stiffness, morphology, and muscle architecture were determined using ultrasonography. The force–length relation of the plantar flexor muscles was assessed at five ankle joint angles. In addition, simulations (OpenSim) of the GM MTU force–length properties were performed with various iterations of MTU properties found between the unaffected and the affected side. Results: The affected side of the patients displayed a longer, larger, and stiffer GM tendon (13% ± 10%, 105% ± 28%, and 54% ± 24%, respectively) compared with the unaffected side. The GM muscle fascicles of the affected side were shorter (32% ± 12%) and with greater pennation angles (31% ± 26%). A mean deficit in plantarflexion moment of 31% ± 10% was measured. Simulations indicate that pairing an intact muscle with a longer tendon shifts the optimal angular range of peak force outside physiological angular ranges, whereas the shorter muscle fascicles and tendon stiffening seen in the affected side decrease this shift, albeit incompletely. Conclusions: These results suggest that the substantial changes in MTU properties found in ATR patients may partly result from compensatory remodeling, although this process appears insufficient to fully restore muscle function. KW - Tendon Rupture KW - Stiffness KW - Simulation KW - Muscle Force KW - Muscle Fascicle Y1 - 2021 U6 - https://doi.org/10.1249/MSS.0000000000002592 SN - 1530-0315 VL - 53 IS - 7 SP - 1356 EP - 1366 PB - American College of Sports Medicine CY - Philadelphia, Pa. ER - TY - CHAP A1 - Dreschers, Martin ED - Mönning, Rolf-Dieter T1 - §25 Arbeitsrechtliche Probleme im Rahmen der Betriebsfortführung T2 - Betriebsfortführung in Restrukturierung und Insolvenz Y1 - 2023 SN - 978-3-8145-2012-4 (print) SN - 978-3-8145-5888-2 (e-book) U6 - https://doi.org/https://doi.org/10.15375/9783814558882-028 SP - 947 EP - 988 PB - RWS Verlag CY - Köln ER - TY - CHAP A1 - Dreschers, Martin ED - Kübler, Bruno M. ED - Bork, Reinhard ED - Prütting, Hanns T1 - §18 Grenzüberschreitende Eigenverwaltung T2 - HRI II - Handbuch Restrukturierung in der Insolvenz Y1 - 2023 SN - 978-3-8145-2010-0 (print) SN - 978-3-8145-5871-4 (e-book) U6 - https://doi.org/10.15375/9783814558714-028 SP - 524 EP - 556 PB - RWS Verlag CY - Köln ER - TY - JOUR A1 - Werkhausen, Amelie A1 - Albracht, Kirsten A1 - Cronin, Neil J A1 - Paulsen, Gøran A1 - Bojsen-Møller, Jens A1 - Seynnes, Olivier R T1 - Effect of training-induced changes in achilles tendon stiffness on muscle-tendon behavior during landing JF - Frontiers in physiology N2 - During rapid deceleration of the body, tendons buffer part of the elongation of the muscle-tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle-tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarflexion force, peak Achilles tendon strain and stiffness were measured during isometric contractions, using a combination of dynamometry, ultrasound and kinematics data. Additionally, testing included a step-landing task, during which joint mechanics and lengths of gastrocnemius and soleus fascicles, Achilles tendon, and MTU were determined using synchronized ultrasound, kinematics and kinetics data collection. After training, plantarflexion strength and Achilles tendon stiffness increased (15 and 18%, respectively), and tendon strain during landing remained similar. Likewise, lengthening and negative work produced by the gastrocnemius MTU did not change detectably. However, in the training group, gastrocnemius fascicle length was offset (8%) to a longer length at touch down and, surprisingly, fascicle lengthening and velocity were reduced by 27 and 21%, respectively. These changes were not observed for soleus fascicles when accounting for variation in task execution between tests. These results indicate that a training-induced increase in tendon stiffness does not noticeably affect the buffering action of the tendon when the MTU is rapidly stretched. Reductions in gastrocnemius fascicle lengthening and lengthening velocity during landing occurred independently from tendon strain. Future studies are required to provide insight into the mechanisms underpinning these observations and their influence on energy dissipation. KW - achilles tendon KW - energy absorption KW - energy dissipation KW - mechanical buffer KW - stiffness Y1 - 2018 U6 - https://doi.org/10.3389/fphys.2018.00794 SN - 1664-042X IS - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Yang, Peng-Fei A1 - Kriechbaumer, Andreas A1 - Albracht, Kirsten A1 - Sanno, Maximilian A1 - Ganse, Bergita A1 - Koy, Timmo A1 - Shang, Peng A1 - brüggemann, Gert-Peter A1 - Müller, Lars Peter A1 - Rittweger, Jörn T1 - A novel optical approach for assessing in vivo bone segment deformation and its application in muscle-bone relationship studies in humans JF - Journal of Orthopaedic Translation Y1 - 2014 U6 - https://doi.org/10.1016/j.jot.2014.07.078 SN - 2214-0328 SN - 2214-031X VL - 2 IS - 4 SP - 238 EP - 238 PB - Elsevier CY - Singapore ER - TY - CHAP A1 - Maurer, Florian A1 - Miskiw, Kim K. A1 - Acosta, Rebeca Ramirez A1 - Harder, Nick A1 - Sander, Volker A1 - Lehnhoff, Sebastian ED - Jorgensen, Bo Norregaard ED - Pereira da Silva, Luiz Carlos ED - Ma, Zheng T1 - Market abstraction of energy markets and policies - application in an agent-based modeling toolbox T2 - EI.A 2023: Energy Informatics N2 - In light of emerging challenges in energy systems, markets are prone to changing dynamics and market design. Simulation models are commonly used to understand the changing dynamics of future electricity markets. However, existing market models were often created with specific use cases in mind, which limits their flexibility and usability. This can impose challenges for using a single model to compare different market designs. This paper introduces a new method of defining market designs for energy market simulations. The proposed concept makes it easy to incorporate different market designs into electricity market models by using relevant parameters derived from analyzing existing simulation tools, morphological categorization and ontologies. These parameters are then used to derive a market abstraction and integrate it into an agent-based simulation framework, allowing for a unified analysis of diverse market designs. Furthermore, we showcase the usability of integrating new types of long-term contracts and over-the-counter trading. To validate this approach, two case studies are demonstrated: a pay-as-clear market and a pay-as-bid long-term market. These examples demonstrate the capabilities of the proposed framework. KW - Energy market design KW - Agent-based simulation KW - Market modeling Y1 - 2023 SN - 978-3-031-48651-7 (Print) SN - 978-3-031-48652-4 (eBook) U6 - https://doi.org/10.1007/978-3-031-48652-4_10 N1 - Energy Informatics Academy Conference, 6-8 December 23, Campinas, Brazil. N1 - Part of the Lecture Notes in Computer Science book series (LNCS,volume 14468). SP - 139 EP - 157 PB - Springer CY - Cham ER - TY - RPRT A1 - Albracht, Kirsten A1 - Ritzmann, Ramona A1 - Kramer, Andreas A1 - Meskemper, Joshua A1 - Stäudle, Benjamin A1 - Kümmel, Jacob A1 - Freyler, Katrin A1 - Felsenberg, Dieter A1 - Gruber, Marksu A1 - Gollhofer, Albert A1 - Belavy, Daniel T1 - Vorhaben: Muskelkraftgenerierungsfähigkeit in Mikrogravitation KW - Elektromyographie KW - Bein KW - Extensor KW - Elektrostimulation KW - Raumfahrt Y1 - 2017 U6 - https://doi.org/10.2314/KXP:1670327353 N1 - Förderkennzeichen: BMWi 50WB1428 Öffentlicher Schlussbericht für die Technische Informationsbibliothek der Universität Hannover Berichtszeitraum: 01.09.2014 - 31.01.2017 PB - Deutsche Sporthochschule Köln CY - Klön ER - TY - CHAP A1 - Schulze-Buxloh, Lina A1 - Groß, Rolf Fritz T1 - Interdisciplinary Course Smart Building Engineering: A new approach of teaching freshmen in remote teamwork project under pandemic restrictions T2 - New Perspectives in Science Education - International Conference N2 - In the context of the Corona pandemic and its impact on teaching like digital lectures and exercises a new concept especially for freshmen in demanding courses of Smart Building Engineering became necessary. As there were hardly any face-to-face events at the university, the new teaching concept should enable a good start into engineering studies under pandemic conditions anyway and should also replace the written exam at the end. The students should become active themselves in small teams instead of listening passively to a lecture broadcast online with almost no personal contact. For this purpose, a role play was developed in which the freshmen had to work out a complete solution to the realistic problem of designing, construction planning and implementing a small guesthouse. Each student of the team had to take a certain role like architect, site manager, BIM-manager, electrician and the technitian for HVAC installations. Technical specifications must be complied with, as well as documentation, time planning and cost estimate. The final project folder had to contain technical documents like circuit diagrams for electrical components, circuit diagrams for water and heating, design calculations and components lists. On the other hand construction schedule, construction implementation plan, documentation of the construction progress and minutes of meetings between the various trades had to be submitted as well. In addition to the project folder, a model of the construction project must also be created either as a handmade model or as a digital 3D-model using Computer-aided design (CAD) software. The first steps in the field of Building information modelling (BIM) had also been taken by creating a digital model of the building showing the current planning status in real time as a digital twin. This project turned out to be an excellent training of important student competencies like teamwork, communication skills, and self -organisation and also increased motivation to work on complex technical questions. The aim of giving the student a first impression on the challenges and solutions in building projects with many different technical trades and their points of view was very well achieved and should be continued in the future. KW - Freshmen KW - roleplay KW - Smart Building Engineering KW - BIM KW - remote teamwork Y1 - 2021 N1 - New Perspectives in Science Education - 10th Edition, 18-19 March 2021, Fully Virtual Conference PB - Filodiritto CY - Bologna ER - TY - CHAP A1 - Schulze-Buxloh, Lina A1 - Groß, Rolf Fritz T1 - Miniature urban farming plant: a complex educational “Toy” for engineering students T2 - The Future of Education 11th Edition 2021 N2 - Urban farming is an innovative and sustainable way of food production and is becoming more and more important in smart city and quarter concepts. It also enables the production of certain foods in places where they usually dare not produced, such as production of fish or shrimps in large cities far away from the coast. Unfortunately, it is not always possible to show students such concepts and systems in real life as part of courses: visits of such industry plants are sometimes not possible because of distance or are permitted by the operator for hygienic reasons. In order to give the students the opportunity of getting into contact with such an urban farming system and its complex operation, an industrial urban farming plant was set up on a significantly smaller scale. Therefore, all needed technical components like water aeriation, biological and mechanical filtration or water circulation have been replaced either by aquarium components or by self-designed parts also using a 3D-printer. Students from different courses like mechanical engineering, smart building engineering, biology, electrical engineering, automation technology and civil engineering were involved in this project. This “miniature industrial plant” was also able to start operation and has now been running for two years successfully. Due to Corona pandemic, home office and remote online lectures, the automation of this miniature plant should be brought to a higher level in future for providing a good control over the system and water quality remotely. The aim of giving the student a chance to get to know the operation of an urban farming plant was very well achieved and the students had lots of fun in “playing” and learning with it in a realistic way. KW - urban farming KW - food production KW - smart engineering KW - 3D printing KW - sustainability Y1 - 2021 N1 - FOE 2021 : The Future of Education International Conference – Fully Virtual Edition; 01.07.2021-02.07.2021; Florence, Italy ER - TY - CHAP A1 - Schulze-Buxloh, Lina A1 - Groß, Rolf Fritz A1 - Ulbrich, Michelle T1 - Digital planning using building information modelling and virtual reality: new approach for students’ remote practical training under lockdown conditions in the course of smart building engineering T2 - Proceedings of International Conference on Education in Mathematics, Science and Technology 2021 N2 - The worldwide Corona pandemic has severely restricted student projects in the higher semesters of engineering courses. In order not to delay the graduation, a new concept had to be developed for projects under lockdown conditions. Therefore, unused rooms at the university should be digitally recorded in order to develop a new usage concept as laboratory rooms. An inventory of the actual state of the rooms was done first by taking photos and listing up all flaws and peculiarities. After that, a digital site measuring was done with a 360° laser scanner and these recorded scans were linked to a coherent point cloud and transferred to a software for planning technical building services and supporting Building Information Modelling (BIM). In order to better illustrate the difference between the actual and target state, two virtual reality models were created for realistic demonstration. During the project, the students had to go through the entire digital planning phases. Technical specifications had to be complied with, as well as documentation, time planning and cost estimate. This project turned out to be an excellent alternative to on-site practical training under lockdown conditions and increased the students’ motivation to deal with complex technical questions. KW - smart building engineering KW - building information modelling KW - virtual reality KW - lockdown conditions KW - emote practical training Y1 - 2021 SN - 978-1-952092-17-6 N1 - International Conference on Education in Mathematics, Science and Technology 2021, April 1-4, 2021 in Antalya, Turkey SP - 118 EP - 123 PB - ISTES Organization CY - San Antonio, TX ER - TY - GEN A1 - Schulze-Buxloh, Lina A1 - Groß, Rolf Fritz A1 - Cheng, Kevin Toni T1 - Development and manufacturing of an interactive three-dimensional phase diagram of carbon dioxide for teaching sessions in thermodynamics T2 - Proceedings of the International Conference The Future of Education 2020 Y1 - 2020 ER - TY - CHAP A1 - Bedbur, Christian A1 - Moorkamp, Wilfried A1 - Peterson, Leif Arne A1 - Uibel, Thomas ED - Kuhlmann, Ulrike T1 - Holzbrücken mit Natursteinbelägen - Untersuchungen zur Aktivierung der Verbundwirkung T2 - Doktorandenkolloquium Holzbau Forschung + Praxis 2020 Y1 - 2020 N1 - 8. Doktorandenkolloquium „Holzbau Forschung + Praxis“, 05. und 06. März 2020, Stuttgart SP - 53 EP - 60 PB - Universität Stuttgart, Institut für Konstruktion und Entwurf CY - Stuttgart ER - TY - JOUR A1 - Angermann, Susanne A1 - Günthner, Roman A1 - Hanssen, Henner A1 - Lorenz, Georg A1 - Braunisch, Matthias C. A1 - Steubl, Dominik A1 - Matschkal, Julia A1 - Kemmner, Stephan A1 - Hausinger, Renate A1 - Block, Zenonas A1 - Haller, Bernhard A1 - Heemann, Uwe A1 - Kotliar, Konstantin A1 - Grimmer, Timo A1 - Schmaderer, Christoph T1 - Cognitive impairment and microvascular function in end-stage renal disease JF - International Journal of Methods in Psychiatric Research (MPR) N2 - Objective Hemodialysis patients show an approximately threefold higher prevalence of cognitive impairment compared to the age-matched general population. Impaired microcirculatory function is one of the assumed causes. Dynamic retinal vessel analysis is a quantitative method for measuring neurovascular coupling and microvascular endothelial function. We hypothesize that cognitive impairment is associated with altered microcirculation of retinal vessels. Methods 152 chronic hemodialysis patients underwent cognitive testing using the Montreal Cognitive Assessment. Retinal microcirculation was assessed by Dynamic Retinal Vessel Analysis, which carries out an examination recording retinal vessels' reaction to a flicker light stimulus under standardized conditions. Results In unadjusted as well as in adjusted linear regression analyses a significant association between the visuospatial executive function domain score of the Montreal Cognitive Assessment and the maximum arteriolar dilation as response of retinal arterioles to the flicker light stimulation was obtained. Conclusion This is the first study determining retinal microvascular function as surrogate for cerebral microvascular function and cognition in hemodialysis patients. The relationship between impairment in executive function and reduced arteriolar reaction to flicker light stimulation supports the involvement of cerebral small vessel disease as contributing factor for the development of cognitive impairment in this patient population and might be a target for noninvasive disease monitoring and therapeutic intervention. KW - cerebral small vessel disease KW - cognitive impairment KW - dialysis KW - retinal vessels Y1 - 2022 U6 - https://doi.org/10.1002/mpr.1909 SN - 1049-8931 (Print) SN - 1557-0657 (Online) VL - 31 IS - 2 SP - 1 EP - 10 PB - Wiley ER - TY - JOUR A1 - Kotliar, Konstantin A1 - Ortner, Marion A1 - Conradi, Anna A1 - Hacker, Patricia A1 - Hauser, Christine A1 - Günthner, Roman A1 - Moser, Michaela A1 - Muggenthaler, Claudia A1 - Diehl-Schmid, Janine A1 - Priller, Josef A1 - Schmaderer, Christoph A1 - Grimmer, Timo T1 - Altered retinal cerebral vessel oscillation frequencies in Alzheimer's disease compatible with impaired amyloid clearance JF - Neurobiology of Aging N2 - Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis. KW - Alzheimer's disease KW - Retinal vessel analysis KW - Vasomotions KW - Pulsations KW - Mild cognitive impairment Y1 - 2022 U6 - https://doi.org/10.1016/j.neurobiolaging.2022.08.012 SN - 0197-4580 VL - 120 SP - 117 EP - 127 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Neumaier, Felix A1 - Weiss, Miriam A1 - Veldeman, Michael A1 - Kotliar, Konstantin A1 - Wiesmann, Martin A1 - Schulze-Steinen, Henna A1 - Höllig, Anke A1 - Clusmann, Hans A1 - Schubert, Gerrit Alexander A1 - Albanna, Walid T1 - Changes in endogenous daytime melatonin levels after aneurysmal subarachnoid hemorrhage – preliminary findings from an observational cohort study JF - Clinical Neurology and Neurosurgery N2 - Aneurysmal subarachnoid hemorrhage (aSAH) is associated with early and delayed brain injury due to several underlying and interrelated processes, which include inflammation, oxidative stress, endothelial, and neuronal apoptosis. Treatment with melatonin, a cytoprotective neurohormone with anti-inflammatory, anti-oxidant and anti-apoptotic effects, has been shown to attenuate early brain injury (EBI) and to prevent delayed cerebral vasospasm in experimental aSAH models. Less is known about the role of endogenous melatonin for aSAH outcome and how its production is altered by the pathophysiological cascades initiated during EBI. In the present observational study, we analyzed changes in melatonin levels during the first three weeks after aSAH. KW - constructive alignment KW - examination KW - long-term retention KW - multimodal KW - practical learning Y1 - 2021 U6 - https://doi.org/10.1016/j.clineuro.2021.106870 SN - 0303-8467 VL - 208 IS - Article No.: 106870 PB - Elsevier CY - Amsterdam ER -