@phdthesis{Herok2024, author = {Herok, Christoph}, title = {Quantum Chemical Exploration of Potential Energy Surfaces: Reaction Cycles and Luminescence Phenomena}, doi = {10.25972/OPUS-35218}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-352185}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2024}, abstract = {This work aims at elucidating chemical processes involving homogeneous catalysis and photo-physical relaxation of excited molecules in the solid state. Furthermore, compounds with supposedly small singlet-triplet gaps and therefore biradicaloid character are investigated with respect to their electro-chemical behavior. The work on hydroboration catalysis via a reduced 9,10-diboraanthracene (DBA) was preformed in collaboration with the Wagner group in Frankfurt, more specifically Dr. Sven Prey, who performed all laboratory experiments. The investigation of delayed luminescence properties in arylboronic esters in their solid state was conducted in collaboration with the Marder group in W{\"u}rzburg. The author of this work took part in the synthesis of the investigated compounds while being supervised by Dr. Zhu Wu. The final project was a collaboration with the group of Anukul Jana from Hyderabad, India who provided the experimental data.}, subject = {Simulation}, language = {en} } @article{SchlundGermanPruckner2022, author = {Schlund, Jonas and German, Reinhard and Pruckner, Marco}, title = {Synergy of unidirectional and bidirectional smart charging of electric vehicles for frequency containment reserve power provision}, series = {World Electric Vehicle Journal}, volume = {13}, journal = {World Electric Vehicle Journal}, number = {9}, issn = {2032-6653}, doi = {10.3390/wevj13090168}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-288324}, year = {2022}, abstract = {Besides the integration of renewable energies, electric vehicles pose an additional challenge to modern power grids. However, electric vehicles can also be a flexibility source and contribute to the power system stability. Today, the power system still heavily relies on conventional technologies to stay stable. In order to operate a future power system based on renewable energies only, we need to understand the flexibility potential of assets such as electric vehicles and become able to use their flexibility. In this paper, we analyzed how vast amounts of coordinated charging processes can be used to provide frequency containment reserve power, one of the most important ancillary services for system stability. Therefore, we used an extensive simulation model of a virtual power plant of millions of electric vehicles. The model considers not only technical components but also the stochastic behavior of electric vehicle drivers based on real data. Our results show that, in 2030, electric vehicles have the potential to serve the whole frequency containment reserve power market in Germany. We differentiate between using unidirectional and bidirectional chargers. Bidirectional chargers have a larger potential but also result in unwanted battery degradation. Unidirectional chargers are more constrained in terms of flexibility, but do not lead to additional battery degradation. We conclude that using a mix of both can combine the advantages of both worlds. Thereby, average private cars can provide the service without any notable additional battery degradation and achieve yearly earnings between EUR 200 and EUR 500, depending on the volatile market prices. Commercial vehicles have an even higher potential, as the results increase with vehicle utilization and consumption.}, language = {en} } @article{KieselBeyersKaliszetal.2022, author = {Kiesel, Matthias and Beyers, Inga and Kalisz, Adam and W{\"o}ckel, Achim and L{\"o}b, Sanja and Schlaiss, Tanja and Wulff, Christine and Diessner, Joachim}, title = {Evaluating a novel 3D printed model for simulating Large Loop Excision of the Transformation Zone (LLETZ)}, series = {3D Printing in Medicine}, volume = {8}, journal = {3D Printing in Medicine}, doi = {10.1186/s41205-022-00143-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313356}, year = {2022}, abstract = {Background Electrosurgical excisions are common procedures for treating cervical dysplasia and are often seen as minor surgeries. Yet, thorough training of this intervention is required, as there are considerable consequences of inadequate resections, e.g. preterm birth, the risk of recurrence, injuries and many more. Unfortunately, there is a lack of sufficiently validated possibilities of simulating electrosurgeries, which focus on high fidelity and patient safety. Methods A novel 3D printed simulator for examination and electrosurgical treatment of dysplastic areas of the cervix was compared with a conventional simulator. Sixty medical students experienced a seminar about cervical dysplasia. Group A underwent the seminar with the conventional and Group B with the novel simulator. After a theoretical introduction, the students were randomly assigned by picking a ticket from a box and went on to perform the hands-on training with their respective simulator. Each student first obtained colposcopic examination training. Then he or she performed five electrosurgical excisions (each). This was assessed with a validated score, to visualize their learning curve. Furthermore, adequate and inadequate resections and contacts between electrosurgical loop and vagina or speculum were counted. Both groups also assessed the seminar and their simulator with 18 questions (Likert-scales, 1-10, 1 = strongly agree / very good, 10 = strongly disagree / very bad). Group B additionally assessed the novel simulator with four questions (similar Likert-scales, 1-10). Results Nine of 18 questions showed statistically significant differences favoring Group B (p < 0.05). Group B also achieved more adequate R0-resections and less contacts between electrosurgical loop and vagina or speculum. The learning curves of the performed resections favored the novel simulator of Group B without statistically significant differences. The four questions focusing on certain aspects of the novel simulator indicate high appreciation of the students with a mean score of 1.6 points. Conclusion The presented novel simulator shows several advantages compared to the existing model. Thus, novice gynecologists can be supported with a higher quality of simulation to improve their training and thereby patient safety.}, language = {en} } @phdthesis{Geissler2022, author = {Geißler, Stefan}, title = {Performance Evaluation of Next-Generation Data Plane Architectures and their Components}, issn = {1432-8801}, doi = {10.25972/OPUS-26015}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260157}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {In this doctoral thesis we cover the performance evaluation of next generation data plane architectures, comprised of complex software as well as programmable hardware components that allow fine granular configuration. In the scope of the thesis we propose mechanisms to monitor the performance of singular components and model key performance indicators of software based packet processing solutions. We present novel approaches towards network abstraction that allow the integration of heterogeneous data plane technologies into a singular network while maintaining total transparency between control and data plane. Finally, we investigate a full, complex system consisting of multiple software-based solutions and perform a detailed performance analysis. We employ simulative approaches to investigate overload control mechanisms that allow efficient operation under adversary conditions. The contributions of this work build the foundation for future research in the areas of network softwarization and network function virtualization.}, subject = {Leistungsbewertung}, language = {en} } @article{McIlroyPassfieldHolmbergetal.2021, author = {McIlroy, Benjamin and Passfield, Louis and Holmberg, Hans-Christer and Sperlich, Billy}, title = {Virtual training of endurance cycling - A summary of strengths, weaknesses, opportunities and threats}, series = {Frontiers in Sports and Active Living}, volume = {3}, journal = {Frontiers in Sports and Active Living}, doi = {10.3389/fspor.2021.631101}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258876}, year = {2021}, abstract = {Virtual online training has emerged as one of the top 20 worldwide fitness trends for 2021 and continues to develop rapidly. Although this allows the cycling community to engage in virtual training and competition, critical evaluation of virtual training platforms is limited. Here, we discuss the strengths, weaknesses, opportunities and threats associated with virtual training technology and cycling in an attempt to enhance awareness of such aspects. Strengths include immersive worlds, innovative drafting mechanics, and versatility. Weaknesses include questionable data accuracy, inadequate strength and reliability of power-speed algorithms. Opportunities exist for expanding strategic partnerships with major cycling races, brands, and sponsors and improving user experience with the addition of video capture and "e-coaching." Threats are present in the form of cheating during competition, and a lack of uptake and acceptance by a broader community.}, language = {en} } @article{vanToorNewmanTakekawaetal.2016, author = {van Toor, Mari{\"e}lle L. and Newman, Scott H. and Takekawa, John Y. and Wegmann, Martin and Safi, Kamran}, title = {Temporal segmentation of animal trajectories informed by habitat use}, series = {Ecosphere}, volume = {7}, journal = {Ecosphere}, number = {10}, doi = {10.1002/ecs2.1498}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164970}, pages = {e01498}, year = {2016}, abstract = {Most animals live in seasonal environments and experience very different conditions throughout the year. Behavioral strategies like migration, hibernation, and a life cycle adapted to the local seasonality help to cope with fluctuations in environmental conditions. Thus, how an individual utilizes the environment depends both on the current availability of habitat and the behavioral prerequisites of the individual at that time. While the increasing availability and richness of animal movement data has facilitated the development of algorithms that classify behavior by movement geometry, changes in the environmental correlates of animal movement have so far not been exploited for a behavioral annotation. Here, we suggest a method that uses these changes in individual-environment associations to divide animal location data into segments of higher ecological coherence, which we term niche segmentation. We use time series of random forest models to evaluate the transferability of habitat use over time to cluster observational data accordingly. We show that our method is able to identify relevant changes in habitat use corresponding to both changes in the availability of habitat and how it was used using simulated data, and apply our method to a tracking data set of common teal (Anas crecca). The niche segmentation proved to be robust, and segmented habitat suitability outperformed models neglecting the temporal dynamics of habitat use. Overall, we show that it is possible to classify animal trajectories based on changes of habitat use similar to geometric segmentation algorithms. We conclude that such an environmentally informed classification of animal trajectories can provide new insights into an individuals' behavior and enables us to make sensible predictions of how suitable areas might be connected by movement in space and time.}, language = {en} } @article{SarukhanyanShityakovDandekar2018, author = {Sarukhanyan, Edita and Shityakov, Sergey and Dandekar, Thomas}, title = {In silico designed Axl receptor blocking drug candidates against Zika virus infection}, series = {ACS Omega}, volume = {3}, journal = {ACS Omega}, number = {5}, doi = {10.1021/acsomega.8b00223}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176739}, pages = {5281-5290}, year = {2018}, abstract = {After a large outbreak in Brazil, novel drugs against Zika virus became extremely necessary. Evaluation of virus-based pharmacological strategies concerning essential host factors brought us to the idea that targeting the Axl receptor by blocking its dimerization function could be critical for virus entry. Starting from experimentally validated compounds, such as RU-301, RU-302, warfarin, and R428, we identified a novel compound 2′ (R428 derivative) to be the most potent for this task amongst a number of alternative compounds and leads. The improved affinity of compound 2′ was confirmed by molecular docking as well as molecular dynamics simulation techniques using implicit solvation models. The current study summarizes a new possibility for inhibition of the Axl function as a potential target for future antiviral therapies.}, language = {en} } @article{EgetemeirStennekenKoehleretal.2011, author = {Egetemeir, Johanna and Stenneken, Prisca and Koehler, Saskia and Fallgatter, Andreas J. and Herrmann, Martin J.}, title = {Exploring the neural basis of real-life joint action: measuring brain activation during joint table setting with functional near-infrared spectroscopy}, series = {FRONTIERS IN HUMAN NEUROSCIENCE}, volume = {5}, journal = {FRONTIERS IN HUMAN NEUROSCIENCE}, number = {9, Artikel 95}, doi = {10.3389/fnhum.2011.00095}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137054}, pages = {1-9}, year = {2011}, abstract = {Many every-day life situations require two or more individuals to execute actions together. Assessing brain activation during naturalistic tasks to uncover relevant processes underlying such real-life joint action situations has remained a methodological challenge. In the present study, we introduce a novel joint action paradigm that enables the assessment of brain activation during real-life joint action tasks using functional near-infrared spectroscopy (fNIRS). We monitored brain activation of participants who coordinated complex actions with a partner sitting opposite them. Participants performed table setting tasks, either alone (solo action) or in cooperation with a partner (joint action), or they observed the partner performing the task (action observation). Comparing joint action and solo action revealed stronger activation (higher [oxy-Hb]-concentration) during joint action in a number of areas. Among these were areas in the inferior parietal lobule (IPL) that additionally showed an overlap of activation during action observation and solo action. Areas with such a close link between action observation and action execution have been associated with action simulation processes. The magnitude of activation in these IPL areas also varied according to joint action type and its respective demand on action simulation. The results validate fNIRS as an imaging technique for exploring the functional correlates of interindividual action coordination in real-life settings and suggest that coordinating actions in real-life situations requires simulating the actions of the partner.}, language = {en} } @article{HeddergottKruegerBabuetal.2012, author = {Heddergott, Niko and Kr{\"u}ger, Timothy and Babu, Sujin B. and Wei, Ai and Stellamanns, Erik and Uppaluri, Sravanti and Pfohl, Thomas and Stark, Holger and Engstler, Markus}, title = {Trypanosome Motion Represents an Adaptation to the Crowded Environment of the Vertebrate Bloodstream}, series = {PLoS Pathogens}, volume = {8}, journal = {PLoS Pathogens}, number = {11}, doi = {10.1371/journal.ppat.1003023}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134595}, pages = {e1003023}, year = {2012}, abstract = {Blood is a remarkable habitat: it is highly viscous, contains a dense packaging of cells and perpetually flows at velocities varying over three orders of magnitude. Only few pathogens endure the harsh physical conditions within the vertebrate bloodstream and prosper despite being constantly attacked by host antibodies. African trypanosomes are strictly extracellular blood parasites, which evade the immune response through a system of antigenic variation and incessant motility. How the flagellates actually swim in blood remains to be elucidated. Here, we show that the mode and dynamics of trypanosome locomotion are a trait of life within a crowded environment. Using high-speed fluorescence microscopy and ordered micro-pillar arrays we show that the parasites mode of motility is adapted to the density of cells in blood. Trypanosomes are pulled forward by the planar beat of the single flagellum. Hydrodynamic flow across the asymmetrically shaped cell body translates into its rotational movement. Importantly, the presence of particles with the shape, size and spacing of blood cells is required and sufficient for trypanosomes to reach maximum forward velocity. If the density of obstacles, however, is further increased to resemble collagen networks or tissue spaces, the parasites reverse their flagellar beat and consequently swim backwards, in this way avoiding getting trapped. In the absence of obstacles, this flagellar beat reversal occurs randomly resulting in irregular waveforms and apparent cell tumbling. Thus, the swimming behavior of trypanosomes is a surprising example of micro-adaptation to life at low Reynolds numbers. For a precise physical interpretation, we compare our high-resolution microscopic data to results from a simulation technique that combines the method of multi-particle collision dynamics with a triangulated surface model. The simulation produces a rotating cell body and a helical swimming path, providing a functioning simulation method for a microorganism with a complex swimming strategy.}, language = {en} } @article{GrundgeigerAlbertReinhardtetal.2016, author = {Grundgeiger, T. and Albert, M. and Reinhardt, D. and Happel, O. and Steinisch, A. and Wurmb, T.}, title = {Real-time tablet-based resuscitation documentation by the team leader: evaluating documentation quality and clinical performance}, series = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, volume = {24}, journal = {Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine}, number = {51}, doi = {10.1186/s13049-016-0242-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146582}, year = {2016}, abstract = {Background Precise and complete documentation of in-hospital cardiopulmonary resuscitations is important but data quality can be poor. In the present study, we investigated the effect of a tablet-based application for real-time resuscitation documentation used by the emergency team leader on documentation quality and clinical performance of the emergency team. Methods Senior anaesthesiologists either used the tablet-based application during the simulated resuscitation for documentation and also used the application for the final documentation or conducted the full documentation at the end of the scenario using the local hospital information system. The latter procedure represents the current local documentation method. All scenarios were video recorded. To assess the documentation, we compared the precision of intervention delivery times, documentation completeness, and final documentation time. To assess clinical performance, we compared adherence to guidelines for defibrillation and adrenaline administration, the no-flow fraction, and the time to first defibrillation. Results The results showed significant benefits for the tablet-based application compared to the hospital information system for precision of the intervention delivery times, the final documentation time, and the no-flow fraction. We observed no differences between the groups for documentation completeness, adherence to guidelines for defibrillation and adrenaline administration, and the time to first defibrillation. Discussion In the presented study, we observed that a tablet-based application can improve documentation data quality. Furthermore, we demonstrated that a well-designed application can be used in real-time by a member of the emergency team with possible beneficial effects on clinical performance. Conclusion The present evaluation confirms the advantage of tablet-based documentation tools and also shows that the application can be used by an active member of an emergency team without compromising clinical performance.}, language = {en} }