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3. Towards a Muon Collider

Author

Accettura, Carlotta, Adams, Dean, Agarwal, Rohit, Ahdida, Claudia, Aimè, Chiara, Amapane, Nicola, Amorim, David, Andreetto, Paolo, Anulli, Fabio, Appleby, Robert, Apresyan, Artur, Apyan, Aram, Arsenyev, Sergey, Asadi, Pouya, Mahmoud, Mohammed Attia, Azatov, Aleksandr, Back, John, Balconi, Lorenzo, Bandiera, Laura, Barlow, Roger, Bartosik, Nazar, Barzi, Emanuela, Batsch, Fabian, Bauce, Matteo, Berg, J. Scott, Bersani, Andrea, Bertarelli, Alessandro, Bertolin, Alessandro, Boattini, Fulvio, Bogacz, Alex, Bonesini, Maurizio, Bordini, Bernardo, Bottaro, Salvatore, Bottura, Luca, Braghieri, Alessandro, Breschi, Marco, Bruhwiler, Natalie, Buffat, Xavier, Buonincontri, Laura, Burrows, Philip, Burt, Graeme, Buttazzo, Dario, Caiffi, Barbara, Calviani, Marco, Calzaferri, Simone, Calzolari, Daniele, Capdevilla, Rodolfo, Carli, Christian, Casaburo, Fausto, Casarsa, Massimo, Castelli, Luca, Catanesi, Maria Gabriella, Cavoto, Gianluca, Celiberto, Francesco Giovanni, Celona, Luigi, Cerri, Alessandro, Cesarini, Gianmario, Cesarotti, Cari, Chachamis, Grigorios, Chance, Antoine, Chen, Siyu, Chien, Yang-Ting, Chiesa, Mauro, Colaleo, Anna, Collamati, Francesco, Collazuol, Gianmaria, Costa, Marco, Craig, Nathaniel, Curatolo, Camilla, Curtin, David, Da Molin, Giacomo, Dam, Magnus, Damerau, Heiko, Dasu, Sridhara, de Blas, Jorge, De Curtis, Stefania, De Matteis, Ernesto, De Rosa, Stefania, Delahaye, Jean-Pierre, Denisov, Dmitri, Denizli, Haluk, Densham, Christopher, Dermisek, Radovan, Di Luzio, Luca, Di Meco, Elisa, Di Micco, Biagio, Dienes, Keith, Diociaiuti, Eleonora, Dorigo, Tommaso, Dudarev, Alexey, Edgecock, Robert, Errico, Filippo, Fabbrichesi, Marco, Farinon, Stefania, Ferrari, Anna, Somoza, Jose Antonio Ferreira, Filthaut, Frank, Fiorina, Davide, Fol, Elena, Forslund, Matthew, Franceschini, Roberto, Ximenes, Rui Franqueira, Gabrielli, Emidio, Gallinaro, Michele, Garosi, Francesco, Giambastiani, Luca, Gianelle, Alessio, Gilardoni, Simone, Giove, Dario Augusto, Giraldin, Carlo, Glioti, Alfredo, Greco, Mario, Greljo, Admir, Groeber, Ramona, Grojean, Christophe, Grudiev, Alexej, Gu, Jiayin, Han, Chengcheng, Han, Tao, Hauptman, John, Henning, Brian, Hermanek, Keith, Herndon, Matthew, Holmes, Tova Ray, Homiller, Samuel, Huang, Guoyuan, Jana, Sudip, Jindariani, Sergo, Kahn, Yonatan, Karpov, Ivan, Kelliher, David, Kilian, Wolfgang, Kolehmainen, Antti, Kong, Kyoungchul, Koppenburg, Patrick, Kreher, Nils, Krintiras, Georgios, Krizka, Karol, Krnjaic, Gordan, Kumar, Nilanjana, Lechner, Anton, Lee, Lawrence, Li, Qiang, Voti, Roberto Li, Lipton, Ronald, Liu, Zhen, Lomte, Shivani, Long, Kenneth, Gomez, Jose Lorenzo, Losito, Roberto, Low, Ian, Lu, Qianshu, Lucchesi, Donatella, Ma, Lianliang, Ma, Yang, Machida, Shinji, Maltoni, Fabio, Mandurrino, Marco, Mansoulie, Bruno, Mantani, Luca, Marchand, Claude, Mariotto, Samuele, Martin-Haugh, Stewart, Marzocca, David, Mastrapasqua, Paola, Mauro, Giorgio, Mazzolari, Andrea, McGinnis, Navin, Meade, Patrick, Mele, Barbara, Meloni, Federico, Mentink, Matthias, Merlassino, Claudia, Metral, Elias, Miceli, Rebecca, Milas, Natalia, Mokhov, Nikolai, Montella, Alessandro, Mulder, Tim, Musenich, Riccardo, Nardecchia, Marco, Nardi, Federico, Neufeld, Niko, Neuffer, David, Onel, Yasar, Orestano, Domizia, Paesani, Daniele, Griso, Simone Pagan, Palmer, Mark, Panci, Paolo, Panico, Giuliano, Paparella, Rocco, Paradisi, Paride, Passeri, Antonio, Pastrone, Nadia, Pellecchia, Antonello, Piccinini, Fulvio, Portone, Alfredo, Potamianos, Karolos, Prioli, Marco, Quettier, Lionel, Radicioni, Emilio, Radogna, Raffaella, Rattazzi, Riccardo, Redigolo, Diego, Reina, Laura, Resseguie, Elodie, Reuter, Jürgen, Ribani, Pier Luigi, Riccardi, Cristina, Ricci, Lorenzo, Ricciardi, Stefania, Ristori, Luciano, Robens, Tania Natalie, Rodejohann, Werner, Rogers, Chris, Romagnoni, Marco, Ronald, Kevin, Rossi, Lucio, Ruiz, Richard, Queiroz, Farinaldo S., Sala, Filippo, Sala, Paola, Salko, Jakub, Salvini, Paola, Salvioni, Ennio, Santiago, Jose, Sarra, Ivano, Esteban, Francisco Javier Saura, Schieck, Jochen, Schulte, Daniel, Selvaggi, Michele, Senatore, Carmine, Senol, Abdulkadir, Sertore, Daniele, Sestini, Lorenzo, Sharma, Varun, Shiltsev, Vladimir, Shu, Jing, Simone, Federica Maria, Simoniello, Rosa, Skoufaris, Kyriacos, Sorbi, Massimo, Sorti, Stefano, Stamerra, Anna, Stapnes, Steinar, Stark, Giordon Holtsberg, Statera, Marco, Stechauner, Bernd, Stolarski, Daniel, Stratakis, Diktys, Su, Shufang, Su, Wei, Sumensari, Olcyr, Sun, Xiaohu, Sundrum, Raman, Swiatlowski, Maximilian J, Sytov, Alexei, Kuchma, Benjamin T., Tait, Tim M. P., Tang, Jian, Tang, Jingyu, Tesi, Andrea, Testoni, Pietro, Thomas, Brooks, Thompson, Emily Anne, Torre, Riccardo, Tortora, Ludovico, Tortora, Luca, Trifinopoulos, Sokratis, Vai, Ilaria, Valente, Riccardo, Valente, Riccardo Umberto, Valente, Marco, Valenti, Alessandro, Valle, Nicolò, van Rienen, Ursula, Venditti, Rosamaria, Verweij, Arjan, Verwilligen, Piet, Vittorio, Ludovico, Vitulo, Paolo, Wang, Liantao, Weber, Hannsjorg, Wozniak, Mariusz, Wu, Richard, Wu, Yongcheng, Wulzer, Andrea, Xie, Keping, Yamamoto, Akira, Yang, Yifeng, Yonehara, Katsuya, Zaza, Angela, Zhao, Xiaoran, Zlobin, Alexander, Zuliani, Davide, and Zurita, Jose

Subjects
Physics - Accelerator Physics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10~TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work., Comment: 118 pages, 103 figures

Published
2023

4. Validation-Oriented Modelling of Electrical Stimulation Chambers for Cartilage Tissue Engineering

Author

Che, Lam Vien, Zimmermann, Julius, Bathel, Henning, Weizel, Alina, Seitz, Hermann, van Rienen, Ursula, Bock, Hans Georg, Series Editor, de Hoog, Frank, Series Editor, Friedman, Avner, Series Editor, Gupta, Arvind, Series Editor, Nachbin, André, Series Editor, Ozawa, Tohru, Series Editor, Pulleyblank, William R., Series Editor, Rusten, Torgeir, Series Editor, Santosa, Fadil, Series Editor, Seo, Jin Keun, Series Editor, Tornberg, Anna-Karin, Series Editor, van Beurden, Martijn, editor, Budko, Neil V., editor, Ciuprina, Gabriela, editor, Schilders, Wil, editor, Bansal, Harshit, editor, and Barbulescu, Ruxandra, editor

Published
2024
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5. 25 Years Computational Electromagnetics @ SCEE

Author

van Rienen, Ursula, Bock, Hans Georg, Series Editor, de Hoog, Frank, Series Editor, Friedman, Avner, Series Editor, Gupta, Arvind, Series Editor, Nachbin, André, Series Editor, Ozawa, Tohru, Series Editor, Pulleyblank, William R., Series Editor, Rusten, Torgeir, Series Editor, Santosa, Fadil, Series Editor, Seo, Jin Keun, Series Editor, Tornberg, Anna-Karin, Series Editor, van Beurden, Martijn, editor, Budko, Neil V., editor, Ciuprina, Gabriela, editor, Schilders, Wil, editor, Bansal, Harshit, editor, and Barbulescu, Ruxandra, editor

Published
2024
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8. Muon Collider Physics Summary

Author

Aimè, Chiara, Apyan, Aram, Mahmoud, Mohammed Attia, Bartosik, Nazar, Bertolin, Alessandro, Bonesini, Maurizio, Bottaro, Salvatore, Buttazzo, Dario, Capdevilla, Rodolfo, Casarsa, Massimo, Castelli, Luca, Catanesi, Maria Gabriella, Celiberto, Francesco Giovanni, Cerri, Alessandro, Cesarotti, Cari, Chachamis, Grigorios, Chen, Siyu, Chien, Yang-Ting, Chiesa, Mauro, Collazuol, Gianmaria, Costa, Marco, Craig, Nathaniel, Curtin, David, Dasu, Sridhara, De Blas, Jorge, Denisov, Dmitri, Denizli, Haluk, Dermisek, Radovan, Di Luzio, Luca, Di Micco, Biagio, Dienes, Keith, Dorigo, Tommaso, Ferrari, Anna, Fiorina, Davide, Franceschini, Roberto, Garosi, Francesco, Glioti, Alfredo, Greco, Mario, Greljo, Admir, Groeber, Ramona, Grojean, Christophe, Gu, Jiayin, Han, Tao, Henning, Brian, Hermanek, Keith, Holmes, Tova Ray, Homiller, Samuel, Jana, Sudip, Jindariani, Sergo, Kahn, Yonatan, Karpov, Ivan, Kilian, Wolfgang, Kong, Kyoungchul, Koppenburg, Patrick, Krizka, Karol, Lee, Lawrence, Li, Qiang, Lipton, Ronald, Liu, Zhen, Long, Kenneth, Low, Ian, Lucchesi, Donatella, Ma, Yang, Ma, Lianliang, Maltoni, Fabio, Mansoulie, Bruno, Mantani, Luca, Marzocca, David, McGinnis, Navin, Mele, Barbara, Meloni, Federico, Merlassino, Claudia, Montella, Alessandro, Nardecchia, Marco, Nardi, Federico, Panci, Paolo, Griso, Simone Pagan, Panico, Giuliano, Paparella, Rocco, Paradisi, Paride, Pastrone, Nadia, Piccinini, Fulvio, Potamianos, Karolos, Radicioni, Emilio, Rattazzi, Riccardo, Redigolo, Diego, Reina, Laura, Reuter, Jürgen, Riccardi, Cristina, Ricci, Lorenzo, van Rienen, Ursula, Ristori, Luciano, Robens, Tania Natalie, Ruiz, Richard, Sala, Filippo, Salko, Jakub, Salvini, Paola, Salvioni, Ennio, Schulte, Daniel, Selvaggi, Michele, Senol, Abdulkadir, Sestini, Lorenzo, Sharma, Varun, Shu, Jing, Simoniello, Rosa, Stark, Giordon Holtsberg, Stolarski, Daniel, Su, Shufang, Su, Wei, Sumensari, Olcyr, Sun, Xiaohu, Sundrum, Raman, Tang, Jian, Tesi, Andrea, Thomas, Brooks, Torre, Riccardo, Trifinopoulos, Sokratis, Vai, Ilaria, Valenti, Alessandro, Vittorio, Ludovico, Wang, Liantao, Wu, Yongcheng, Wulzer, Andrea, Zhao, Xiaoran, and Zurita, Jose

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

The perspective of designing muon colliders with high energy and luminosity, which is being investigated by the International Muon Collider Collaboration, has triggered a growing interest in their physics reach. We present a concise summary of the muon colliders potential to explore new physics, leveraging on the unique possibility of combining high available energy with very precise measurements., Comment: 21 pages, 7 figures; Contribution to Snowmass 2021

Published
2022

13. rf measurements and tuning of the 1-meter-long 750 MHz radio-frequency quadrupole for artwork analysis

Author

Pommerenke, Hermann W., van Rienen, Ursula, and Grudiev, Alexej

Subjects
Physics - Accelerator Physics
Abstract

The 750 MHz PIXE-RFQ (radio-frequency quadrupole), developed and built at CERN, provides 2 MeV protons over a length of one meter for proton-induced X-ray emission analysis (PIXE) of cultural heritage artwork. In this paper, we report low-power rf measurements and tuning of the PIXE-RFQ, which have been completed mid-2020. Using a novel algorithm based on direct measurements of the response matrix, field and frequency could tuned at the same time in only two steps to satisfying accuracy. Additionally, we report measurements of single modules, quality factors, and coupling strength. In all cases, very good agreement between rf measurement and design values was observed., Comment: 13 pages, 15 figures. Submitted to Physical Review Accelerators and Beams

Published
2020
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14. An Artifact-based Workflow for Finite-Element Simulation Studies

Author

Ruscheinski, Andreas, Wilsdorf, Pia, Zimmermann, Julius, van Rienen, Ursula, and Uhrmacher, Adelinde M.

Subjects
Computer Science - Computational Engineering, Finance, and Science
Abstract

Workflow support typically focuses on single simulation experiments. This is also the case for simulation based on finite element methods. If entire simulation studies shall be supported, flexible means for intertwining revising the model, collecting data, executing and analyzing experiments are required. Artifact-based workflows present one means to support entire simulation studies, as has been shown for stochastic discrete-event simulation. To adapt the approach to finite element methods, the set of artifacts, i.e., conceptual model, requirement, simulation model, and simulation experiment, and the constraints that apply are extended by new artifacts, such as geometrical model, input data, and simulation data. Artifacts, their life cycles, and constraints are revisited revealing features both types of simulation studies share and those they vary in. Also, the potential benefits of exploiting an artifact-based workflow approach are shown based on a concrete simulation study. To those benefits belong guidance to systematically conduct simulation studies, reduction of effort by automatically executing specific steps, e.g., generating and executing convergence tests, and support for the automatic reporting of provenance.

Published
2020

15. Multi-objective design optimization of a Quadrupole Resonator under uncertainties

Author

Putek, Piotr, Zadeh, Shahnam Gorgi, Wenskat, Marc, and van Rienen, Ursula

Subjects
Physics - Accelerator Physics, Physics - Computational Physics
Abstract

For a precise determination of the radio frequency (RF) properties of superconducting materials, a calorimetric measurement is carried out with the aid of a so-called Quadrupole Resonator (QPR). This procedure is affected by certain systematic measurement errors with various sources of uncertainties. In this paper, to reduce the impact of geometrical uncertainties on the measurement bias, the modified steepest descent method is used for the multi-objective shape optimization of a QPR {in terms of an expectation measure}. Thereby, variations of geometrical parameters are modeled by the Polynomial Chaos (PC) expansion technique. Then, the resulting Maxwell's eigenvalue problem with random input data is solved using the PC-based stochastic collocation method (PC-SCM). Furthermore, to assess the contribution of the particular geometrical parameters, the variance-based sensitivity analysis is proposed. This allows for modifying the steepest descent algorithm, which results in reducing the computational load needed to find optimal solutions. Finally, optimization results in the form of an efficient approximation of the Pareto front for a three dimensional (3D) model of the QPR are shown., Comment: 19 pages. 17 figures

Published
2020

16. Uncertainty Modeling and Analysis of the European X-ray Free Electron Laser Cavities Manufacturing Process

Author

Corno, Jacopo, Georg, Niklas, Zadeh, Shahnam Gorgi, Heller, Johann, Gubarev, Vladimir, Roggen, Toon, Römer, Ulrich, Schmidt, Christian, Schöps, Sebastian, Schultz, Julius, Sulimov, Alexey, and van Rienen, Ursula

Subjects
Computer Science - Computational Engineering, Finance, and Science, Physics - Accelerator Physics
Abstract

This paper reports on comprehensive efforts on uncertainty quantification and global sensitivity analysis for accelerator cavity design. As a case study object the TESLA shaped superconducting cavities, as produced for the European X-ray Free Electron Laser (EXFEL), are selected. The choice for these cavities is explained by the available measurement data that can be leveraged to substantiate the simulation model. Each step of the manufacturing chain is documented together with the involved uncertainties. Several of these steps are mimicked on the simulation side, e.g. by introducing a random eigenvalue problem. The uncertainties are then quantified numerically and in particular the sensitivities give valuable insight into the systems behavior. We also compare these findings to purely statistical studies carried out for the manufactured cavities. More advanced, adaptive, surrogate modeling techniques are adopted, which are crucial to incorporate a large number of uncertain parameters. The main contribution is the detailed comparison and fusion of measurement results for the EXFEL cavities on the one hand and simulation based uncertainty studies on the other hand. After introducing the quantities of physical interest for accelerator cavities and the Maxwell eigenvalue problem, the details on the manufacturing of the EXFEL cavities and measurements are reported. This is followed by uncertainty modeling with quantification studies.

Published
2019
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17. Constrained multi-objective shape optimization of superconducting RF cavities considering robustness against geometric perturbations

Author

Kranjcevic, Marija, Zadeh, Shahnam Gorgi, Adelmann, Andreas, Arbenz, Peter, and van Rienen, Ursula

Subjects
Physics - Accelerator Physics
Abstract

High current storage rings, such as the Z-pole operating mode of the FCC-ee, require accelerating cavities that are optimized with respect to both the fundamental mode and the higher order modes. Furthermore, the cavity shape needs to be robust against geometric perturbations which could, for example, arise from manufacturing inaccuracies or harsh operating conditions at cryogenic temperatures. This leads to a constrained multi-objective shape optimization problem which is computationally expensive even for axisymmetric cavity shapes. In order to decrease the computation cost, a global sensitivity analysis is performed and its results are used to reduce the search space and redefine the objective functions. A massively parallel implementation of an evolutionary algorithm, combined with a fast axisymmetric Maxwell eigensolver and a frequency-tuning method is used to find an approximation of the Pareto front. The computed Pareto front approximation and a cavity shape with desired properties are shown. Further, the approach is generalized and applied to another type of cavity., Comment: Submitted to Physical Review Accelerators and Beams

Published
2019
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19. Lead-DBS v3.0: Mapping deep brain stimulation effects to local anatomy and global networks

Author

Neudorfer, Clemens, Butenko, Konstantin, Oxenford, Simon, Rajamani, Nanditha, Achtzehn, Johannes, Goede, Lukas, Hollunder, Barbara, Ríos, Ana Sofía, Hart, Lauren, Tasserie, Jordy, Fernando, Kavisha B., Nguyen, T. A. Khoa, Al-Fatly, Bassam, Vissani, Matteo, Fox, Michael, Richardson, R. Mark, van Rienen, Ursula, Kühn, Andrea A., Husch, Andreas D., Opri, Enrico, Dembek, Till, Li, Ningfei, and Horn, Andreas

Published
2023
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23. Uncertainty Quantification of Oscillation Suppression during DBS in a Coupled Finite Element and Network Model

Author

Schmidt, Christian, Dunn, Eleanor, Lowery, Madeleine, and van Rienen, Ursula

Subjects
Quantitative Biology - Neurons and Cognition, Computer Science - Computational Engineering, Finance, and Science
Abstract

Models of the cortico-basal ganglia network and volume conductor models of the brain can provide insight into the mechanisms of action of deep brain stimulation (DBS). In this study, the coupling of a network model, under parkinsonian conditions, to the extracellular field distribution obtained from a three dimensional finite element model of a rodent's brain during DBS is presented. This coupled model is used to investigate the influence of uncertainty in the electrical properties of brain tissue and encapsulation tissue, formed around the electrode after implantation, on the suppression of oscillatory neural activity during DBS. The resulting uncertainty in this effect of DBS on the network activity is quantified using a computationally efficient and non-intrusive stochastic approach based on the generalized Polynomial Chaos. The results suggest that variations in the electrical properties of brain tissue may have a substantial influence on the level of suppression of oscillatory activity during DBS. Applying a global sensitivity analysis on the suppression of the simulated oscillatory activity showed that the influence of uncertainty in the electrical properties of the encapsulation tissue had only a minor influence, in agreement with previous experimental and computational studies investigating the mechanisms of current-controlled DBS in the literature., Comment: 10 pages

Published
2017
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24. Adaptive Estimation of the Neural Activation Extent in Computational Volume Conductor Models of Deep Brain Stimulation

Author

Schmidt, Christian and van Rienen, Ursula

Subjects
Quantitative Biology - Neurons and Cognition, Computer Science - Computational Engineering, Finance, and Science
Abstract

Objective: The aim of this study is to propose an adaptive scheme embedded into an open-source environment for the estimation of the neural activation extent during deep brain stimulation and to investigate the feasibility of approximating the neural activation extent by thresholds of the field solution. Methods: Open-source solutions for solving the field equation in volume conductor models of deep brain stimulation and computing the neural activation are embedded into a Python package to estimate the neural activation dependent on the dielectric tissue properties and axon parameters by employing a spatially adaptive scheme. Feasibility of the approximation of the neural activation extent by field thresholds is investigated to further reduce the computational expense. Results: The varying extents of neural activation for different patient-specific dielectric properties were estimated with the adaptive scheme. The results revealed the strong influence of the dielectric properties of the encapsulation layer in the acute and chronic phase after surgery. The computational time required to determine the neural activation extent in each studied model case was substantially reduced. Conclusion: The neural activation extent is altered by patient-specific parameters. Threshold values of the electric potential and electric field norm facilitate a computationally efficient method to estimate the neural activation extent. Significance: The presented adaptive scheme is able to robustly determine neural activation extents and field threshold estimates for varying dielectric tissue properties and axon diameters while reducing substantially the computational expense., Comment: 12 pages

Published
2017

25. Low-Dimensional Stochastic Modeling of the Electrical Properties of Biological Tissues

Author

Römer, Ulrich, Schmidt, Christian, van Rienen, Ursula, and Schöps, Sebastian

Subjects
Computer Science - Computational Engineering, Finance, and Science, Mathematics - Numerical Analysis, 60H30, 60H35, 78M10, G.1.8, I.6.3
Abstract

Uncertainty quantification plays an important role in biomedical engineering as measurement data is often unavailable and literature data shows a wide variability. Using state-of-the-art methods one encounters difficulties when the number of random inputs is large. This is the case, e.g., when using composite Cole-Cole equations to model random electrical properties. It is shown how the number of parameters can be significantly reduced by the Karhunen-Loeve expansion. The low-dimensional random model is used to quantify uncertainties in the axon activation during deep brain stimulation. Numerical results for a Medtronic 3387 electrode design are given., Comment: 4 pages, 5 figures

Published
2016
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31. Addressing Model Uncertainties in Finite Element Simulation of Electrically Stimulated Implants for Critical-Size Mandibular Defects

Author

Raben, Hendrikje, Kammerer, Peer Wolfgang, and van Rienen, Ursula

Abstract

Objective: Electrical stimulation is known to enhance bone healing. Novel electrostimulating devices are currently being developed for the treatment of critical-size bone defects in the mandible. Previous numerical models of these devices did not account for possible uncertainties in the input data. We present the numerical model of an electrically stimulated minipig mandible, including optimization and uncertainty quantification (UQ) methods that allow us to determine the most influential parameters. Methods: Uncertainties in the optimized finite element model are quantified using the polynomial chaos method that is implemented in the open-source Python toolbox Uncertainpy. The volumes of understimulated, beneficially stimulated, and overstimulated tissue are considered quantities of interest because they may significantly impact the expected healing success. Further, the current is a substantial quantity, limiting the lifetime of a battery-driven stimulation unit. With sensitivity analyses, the most critical parameters in the numerical model can be identified. Thus, we can learn which parameters are particularly relevant, for example, when conceptualizing the stimulation unit or planning the manufacturing process. Results: The results of this study show that the parameters of the electrode-tissue interface (ETI), as well as the conductivity within the defect volume, have the most significant impact on the model results. Conclusions: The UQ results suggest that careful characterization of the ETI and the dielectric tissue properties is crucial to reduce these uncertainties. Significance: The numerical model regarding uncertainties yields important implications for reliable implant design and clinical translation.

Published
2024
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33. Towards a muon collider

Author

Accettura, Carlotta, Adams, Dean, Agarwal, Rohit, Ahdida, Claudia, Aime, Chiara, Amapane, Nicola, Amorim, David, Andreetto, Paolo, Anulli, Fabio, Appleby, Robert, Apresyan, Artur, Apyan, Aram, Arsenyev, Sergey, Asadi, Pouya, Mahmoud, Mohammed Attia, Azatov, Aleksandr, Back, John, Balconi, Lorenzo, Bandiera, Laura, Barlow, Roger, Bartosik, Nazar, Barzi, Emanuela, Batsch, Fabian, Bauce, Matteo, Berg, J. Scott, Bersani, Andrea, Bertarelli, Alessandro, Bertolin, Alessandro, Black, Kevin, Boattini, Fulvio, Bogacz, Alex, Bonesini, Maurizio, Bordini, Bernardo, Bottaro, Salvatore, Bottura, Luca, Braghieri, Alessandro, Breschi, Marco, Bruhwiler, Natalie, Buffat, Xavier, Buonincontri, Laura, Burrows, Philip N., Burt, Graeme, Buttazzo, Dario, Caiffi, Barbara, Calviani, Marco, Calzaferri, Simone, Calzolari, Daniele, Capdevilla, Rodolfo, Carli, Christian, Casaburo, Fausto, Casarsa, Massimo, Castelli, Luca, Catanesi, Maria Gabriella, Cavallucci, Lorenzo, Cavoto, Gianluca, Celiberto, Francesco Giovanni, Celona, Luigi, Cerri, Alessandro, Cesarini, Gianmario, Cesarotti, Cari, Chachamis, Grigorios, Chance, Antoine, Chen, Siyu, Chien, Yang-Ting, Chiesa, Mauro, Colaleo, Anna, Collamati, Francesco, Collazuol, Gianmaria, Costa, Marco, Craig, Nathaniel, Curatolo, Camilla, Curtin, David, Da Molin, Giacomo, Dam, Magnus, Damerau, Heiko, Dasu, Sridhara, de Blas, Jorge, De Curtis, Stefania, De Matteis, Ernesto, De Rosa, Stefania, Delahaye, Jean-Pierre, Denisov, Dmitri, Denizli, Haluk, Densham, Christopher, dermisek, RadoVan, Di Luzio, Luca, Di Meco, Elisa, Di Micco, Biagio, Dienes, Keith, Diociaiuti, Eleonora, Dorigo, Tommaso, Dudarev, Alexey, Edgecock, Robert, Errico, Filippo, Fabbrichesi, Marco, Farinon, Stefania, Ferrari, Anna, Somoza, Jose Antonio Ferreira, Filthaut, Frank, Fiorina, Davide, Fol, Elena, Forslund, Matthew, Franceschini, Roberto, Ximenes, Rui Franqueira, Gabrielli, Emidio, Gallinaro, Michele, Garosi, Francesco, Giambastiani, Luca, Gianelle, Alessio, Gilardoni, Simone, Giove, Dario Augusto, Giraldin, Carlo, Glioti, Alfredo, Greco, Mario, Greljo, Admir, Groeber, Ramona, Grojean, Christophe, Grudiev, Alexej, Gu, Jiayin, Han, Chengcheng, Han, Tao, Hauptman, John, Henning, Brian Quinn, Hermanek, Keith, Herndon, Matthew, Holmes, Tova Ray, Homiller, Samuel, Huang, Guoyuan, Jana, Sudip, Jindariani, Sergo, Jurj, Paul Bogdan, Kahn, Yonatan, Karpov, Ivan, Kelliher, David, Kilian, Wolfgang, Kolehmainen, Antti, Kong, Kyoungchul, Koppenburg, Patrick, Kreher, Nils, Krintiras, Georgios, Krizka, Karol, Krnjaic, Gordan, Kuchma, Benjamin T., Kumar, Nilanjana, Lechner, Anton, Lee, Lawrence, Li, Qiang, Voti, Roberto Li, Lipton, Ronald, Liu, Zhen, Lomte, Shivani, Long, Kenneth, Gomez, Jose Lorenzo, Losito, Roberto, Low, Ian, Lu, Qianshu, Lucchesi, Donatella, Ma, Lianliang, Ma, Yang, Machida, Shinji, Maltoni, Fabio, Mandurrino, Marco, Mansoulie, Bruno, Mantani, Luca, Marchand, Claude, Mariotto, Samuele, Martin-Haugh, Stewart, Marzocca, David, Mastrapasqua, Paola, Mauro, Giorgio, Mazzolari, Andrea, McGinnis, Navin, Meade, Patrick, Mele, Barbara, Meloni, Federico, Mentink, Matthias, Merlassino, Claudia, Metral, Elias, Miceli, Rebecca, Milas, Natalia, Mokhov, Nikolai, Montella, Alessandro, Mulder, Tim, Musenich, Riccardo, Nardecchia, Marco, Nardi, Federico, Neufeld, Niko, Neuffer, David, Novelli, Daniel, Onel, Yasar, Orestano, Domizia, Paesani, Daniele, Griso, Simone Pagan, Palmer, Mark, Panci, Paolo, Panico, Giuliano, Paparella, Rocco, Paradisi, Paride, Passeri, Antonio, Pastrone, Nadia, Pellecchia, Antonello, Piccinini, Fulvio, Portone, Alfredo, Potamianos, Karolos, Prioli, Marco, Quettier, Lionel, Radicioni, Emilio, Radogna, Raffaella, Rattazzi, Riccardo, Redigolo, Diego, Reina, Laura, Resseguie, Elodie, Reuter, Jurgen, Ribani, Pier Luigi, Riccardi, Cristina, Ricci, Lorenzo, Ricciardi, Stefania, Ristori, Luciano, Robens, Tania Natalie, Rodejohann, Werner, Rogers, Chris, Romagnoni, Marco, Ronald, Kevin, Rossi, Lucio, Ruiz, Richard, Queiroz, Farinaldo S., Sala, Filippo, Salko, Jakub, Salvini, Paola, Salvioni, Ennio, Santiago, Jose, Sarra, Ivano, Esteban, Francisco Javier Saura, Schieck, Jochen, Schulte, Daniel, Selvaggi, Michele, Senatore, Carmine, Senol, Abdulkadir, Sertore, Daniele, Sestini, Lorenzo, Sharma, Varun, Shiltsev, Vladimir, Shu, Jing, Simone, Federica Maria, Simoniello, Rosa, Skoufaris, Kyriacos, Sorbi, Massimo, Sorti, Stefano, Stamerra, Anna, Stapnes, Steinar, Stark, Giordon Holtsberg, Statera, Marco, Stechauner, Bernd, Stolarski, Daniel, Stratakis, Diktys, Su, Shufang, Su, Wei, Sumensari, Olcyr, Sun, Xiaohu, Sundrum, Raman, Swiatlowski, Maximilian J., Sytov, Alexei, Tait, Tim M. P., Tang, Jingyu, Tang, Jian, Tesi, Andrea, Testoni, Pietro, Thomas, Brooks, Thompson, Emily Anne, Torre, Riccardo, Tortora, Ludovico, Tortora, Luca, Trifinopoulos, Sokratis, Vai, Ilaria, Valente, Marco, Valente, Riccardo Umberto, Valenti, Alessandro, Valle, Nicolo, van Rienen, Ursula, Venditti, Rosamaria, Verweij, Arjan, Verwilligen, Piet, Vittorio, Ludovico, Vitulo, Paolo, Wang, Liantao, Weber, Hannsjorg, Wozniak, Mariusz, Wu, Richard, Wu, Yongcheng, Wulzer, Andrea, Xie, Keping, Yamamoto, Akira, Yang, Yifeng, Yonehara, Katsuya, Yoon, Sangsik, Zaza, Angela, Zhao, Xiaoran, Zlobin, Alexander, Zuliani, Davide, Zurita, Jose, Accettura, Carlotta, Adams, Dean, Agarwal, Rohit, Ahdida, Claudia, Aime, Chiara, Amapane, Nicola, Amorim, David, Andreetto, Paolo, Anulli, Fabio, Appleby, Robert, Apresyan, Artur, Apyan, Aram, Arsenyev, Sergey, Asadi, Pouya, Mahmoud, Mohammed Attia, Azatov, Aleksandr, Back, John, Balconi, Lorenzo, Bandiera, Laura, Barlow, Roger, Bartosik, Nazar, Barzi, Emanuela, Batsch, Fabian, Bauce, Matteo, Berg, J. Scott, Bersani, Andrea, Bertarelli, Alessandro, Bertolin, Alessandro, Black, Kevin, Boattini, Fulvio, Bogacz, Alex, Bonesini, Maurizio, Bordini, Bernardo, Bottaro, Salvatore, Bottura, Luca, Braghieri, Alessandro, Breschi, Marco, Bruhwiler, Natalie, Buffat, Xavier, Buonincontri, Laura, Burrows, Philip N., Burt, Graeme, Buttazzo, Dario, Caiffi, Barbara, Calviani, Marco, Calzaferri, Simone, Calzolari, Daniele, Capdevilla, Rodolfo, Carli, Christian, Casaburo, Fausto, Casarsa, Massimo, Castelli, Luca, Catanesi, Maria Gabriella, Cavallucci, Lorenzo, Cavoto, Gianluca, Celiberto, Francesco Giovanni, Celona, Luigi, Cerri, Alessandro, Cesarini, Gianmario, Cesarotti, Cari, Chachamis, Grigorios, Chance, Antoine, Chen, Siyu, Chien, Yang-Ting, Chiesa, Mauro, Colaleo, Anna, Collamati, Francesco, Collazuol, Gianmaria, Costa, Marco, Craig, Nathaniel, Curatolo, Camilla, Curtin, David, Da Molin, Giacomo, Dam, Magnus, Damerau, Heiko, Dasu, Sridhara, de Blas, Jorge, De Curtis, Stefania, De Matteis, Ernesto, De Rosa, Stefania, Delahaye, Jean-Pierre, Denisov, Dmitri, Denizli, Haluk, Densham, Christopher, dermisek, RadoVan, Di Luzio, Luca, Di Meco, Elisa, Di Micco, Biagio, Dienes, Keith, Diociaiuti, Eleonora, Dorigo, Tommaso, Dudarev, Alexey, Edgecock, Robert, Errico, Filippo, Fabbrichesi, Marco, Farinon, Stefania, Ferrari, Anna, Somoza, Jose Antonio Ferreira, Filthaut, Frank, Fiorina, Davide, Fol, Elena, Forslund, Matthew, Franceschini, Roberto, Ximenes, Rui Franqueira, Gabrielli, Emidio, Gallinaro, Michele, Garosi, Francesco, Giambastiani, Luca, Gianelle, Alessio, Gilardoni, Simone, Giove, Dario Augusto, Giraldin, Carlo, Glioti, Alfredo, Greco, Mario, Greljo, Admir, Groeber, Ramona, Grojean, Christophe, Grudiev, Alexej, Gu, Jiayin, Han, Chengcheng, Han, Tao, Hauptman, John, Henning, Brian Quinn, Hermanek, Keith, Herndon, Matthew, Holmes, Tova Ray, Homiller, Samuel, Huang, Guoyuan, Jana, Sudip, Jindariani, Sergo, Jurj, Paul Bogdan, Kahn, Yonatan, Karpov, Ivan, Kelliher, David, Kilian, Wolfgang, Kolehmainen, Antti, Kong, Kyoungchul, Koppenburg, Patrick, Kreher, Nils, Krintiras, Georgios, Krizka, Karol, Krnjaic, Gordan, Kuchma, Benjamin T., Kumar, Nilanjana, Lechner, Anton, Lee, Lawrence, Li, Qiang, Voti, Roberto Li, Lipton, Ronald, Liu, Zhen, Lomte, Shivani, Long, Kenneth, Gomez, Jose Lorenzo, Losito, Roberto, Low, Ian, Lu, Qianshu, Lucchesi, Donatella, Ma, Lianliang, Ma, Yang, Machida, Shinji, Maltoni, Fabio, Mandurrino, Marco, Mansoulie, Bruno, Mantani, Luca, Marchand, Claude, Mariotto, Samuele, Martin-Haugh, Stewart, Marzocca, David, Mastrapasqua, Paola, Mauro, Giorgio, Mazzolari, Andrea, McGinnis, Navin, Meade, Patrick, Mele, Barbara, Meloni, Federico, Mentink, Matthias, Merlassino, Claudia, Metral, Elias, Miceli, Rebecca, Milas, Natalia, Mokhov, Nikolai, Montella, Alessandro, Mulder, Tim, Musenich, Riccardo, Nardecchia, Marco, Nardi, Federico, Neufeld, Niko, Neuffer, David, Novelli, Daniel, Onel, Yasar, Orestano, Domizia, Paesani, Daniele, Griso, Simone Pagan, Palmer, Mark, Panci, Paolo, Panico, Giuliano, Paparella, Rocco, Paradisi, Paride, Passeri, Antonio, Pastrone, Nadia, Pellecchia, Antonello, Piccinini, Fulvio, Portone, Alfredo, Potamianos, Karolos, Prioli, Marco, Quettier, Lionel, Radicioni, Emilio, Radogna, Raffaella, Rattazzi, Riccardo, Redigolo, Diego, Reina, Laura, Resseguie, Elodie, Reuter, Jurgen, Ribani, Pier Luigi, Riccardi, Cristina, Ricci, Lorenzo, Ricciardi, Stefania, Ristori, Luciano, Robens, Tania Natalie, Rodejohann, Werner, Rogers, Chris, Romagnoni, Marco, Ronald, Kevin, Rossi, Lucio, Ruiz, Richard, Queiroz, Farinaldo S., Sala, Filippo, Salko, Jakub, Salvini, Paola, Salvioni, Ennio, Santiago, Jose, Sarra, Ivano, Esteban, Francisco Javier Saura, Schieck, Jochen, Schulte, Daniel, Selvaggi, Michele, Senatore, Carmine, Senol, Abdulkadir, Sertore, Daniele, Sestini, Lorenzo, Sharma, Varun, Shiltsev, Vladimir, Shu, Jing, Simone, Federica Maria, Simoniello, Rosa, Skoufaris, Kyriacos, Sorbi, Massimo, Sorti, Stefano, Stamerra, Anna, Stapnes, Steinar, Stark, Giordon Holtsberg, Statera, Marco, Stechauner, Bernd, Stolarski, Daniel, Stratakis, Diktys, Su, Shufang, Su, Wei, Sumensari, Olcyr, Sun, Xiaohu, Sundrum, Raman, Swiatlowski, Maximilian J., Sytov, Alexei, Tait, Tim M. P., Tang, Jingyu, Tang, Jian, Tesi, Andrea, Testoni, Pietro, Thomas, Brooks, Thompson, Emily Anne, Torre, Riccardo, Tortora, Ludovico, Tortora, Luca, Trifinopoulos, Sokratis, Vai, Ilaria, Valente, Marco, Valente, Riccardo Umberto, Valenti, Alessandro, Valle, Nicolo, van Rienen, Ursula, Venditti, Rosamaria, Verweij, Arjan, Verwilligen, Piet, Vittorio, Ludovico, Vitulo, Paolo, Wang, Liantao, Weber, Hannsjorg, Wozniak, Mariusz, Wu, Richard, Wu, Yongcheng, Wulzer, Andrea, Xie, Keping, Yamamoto, Akira, Yang, Yifeng, Yonehara, Katsuya, Yoon, Sangsik, Zaza, Angela, Zhao, Xiaoran, Zlobin, Alexander, Zuliani, Davide, and Zurita, Jose

Abstract

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.

Published
2024
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35. Subthalamic nucleus but not entopeduncular nucleus deep brain stimulation enhances neurogenesis in the SVZ-olfactory bulb system of Parkinsonian rats.

Author

Fauser, Mareike, Payonk, Jan Philipp, Weber, Hanna, Statz, Meike, Winter, Christine, Hadar, Ravit, Appali, Revathi, van Rienen, Ursula, Brandt, Moritz D., and Storch, Alexander

Subjects
SUBTHALAMIC nucleus, DEVELOPMENTAL neurobiology, DEEP brain stimulation, NEUROGENESIS, NEURAL stimulation, NEURAL stem cells, ELECTRIC stimulation
Abstract

Introduction: Deep brain stimulation (DBS) is a highly effective treatment option in Parkinson's disease. However, the underlying mechanisms of action, particularly effects on neuronal plasticity, remain enigmatic. Adult neurogenesis in the subventricular zone-olfactory bulb (SVZ-OB) axis and in the dentate gyrus (DG) has been linked to various non-motor symptoms in PD, e.g., memory deficits and olfactory dysfunction. Since DBS affects several of these non-motor symptoms, we analyzed the effects of DBS in the subthalamic nucleus (STN) and the entopeduncular nucleus (EPN) on neurogenesis in 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian rats. Methods: In our study, we applied five weeks of continuous bilateral STN-DBS or EPN-DBS in 6-OHDA-lesioned rats with stable dopaminergic deficits compared to 6-OHDA-lesioned rats with corresponding sham stimulation. We injected two thymidine analogs to quantify newborn neurons early after DBS onset and three weeks later. Immunohistochemistry identified newborn cells co-labeled with NeuN, TH and GABA within the OB and DG. As a putative mechanism, we simulated the electric field distribution depending on the stimulation site to analyze direct electric effects on neural stem cell proliferation. Results: STN-DBS persistently increased the number of newborn dopaminergic and GABAergic neurons in the OB but not in the DG, while EPN-DBS does not impact neurogenesis. These effects do not seem to be mediated via direct electric stimulation of neural stem/progenitor cells within the neurogenic niches. Discussion: Our data support target-specific effects of STN-DBS on adult neurogenesis, a putative modulator of non-motor symptoms in Parkinson's disease. [ABSTRACT FROM AUTHOR]

Published
2024
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37. Preliminary Numerical Study on Electrical Stimulation at Alloplastic Reconstruction Plates of the Mandible

Author

van Rienen, Ursula, Zimmermann, Ulf, Raben, Hendrikje, Kämmerer, Peer W., Bock, Hans Georg, Series Editor, de Hoog, Frank, Series Editor, Friedman, Avner, Series Editor, Gupta, Arvind, Series Editor, Nachbin, André, Series Editor, Ozawa, Tohru, Series Editor, Pulleyblank, William R., Series Editor, Rusten, Torgeir, Series Editor, Santosa, Fadil, Series Editor, Seo, Jin Keun, Series Editor, Tornberg, Anna-Karin, Series Editor, Langer, Ulrich, editor, Amrhein, Wolfgang, editor, and Zulehner, Walter, editor

Published
2018
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43. On Several Green’s Function Methods for Fast Poisson Solver in Free Space

Author

Zheng, Dawei, van Rienen, Ursula, Bock, Hans Georg, Series editor, de Hoog, Frank, Series editor, Friedman, Avner, Series editor, Gupta, Arvind, Series editor, Nachbin, André, Series editor, Ozawa, Tohru, Series editor, Pulleyblank, William R., Series editor, Rusten, Torgeir, Series editor, Santosa, Fadil, Series editor, Seo, Jin Keun, Series editor, Tornberg, Anna-Karin, Series editor, Bartel, Andreas, editor, Clemens, Markus, editor, Günther, Michael, editor, and ter Maten, E. Jan W., editor

Published
2016
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44. Numerical design studies on a novel electrostimulative osteosynthesis system for the mandible

Author

Raben Hendrikje, Schmidt Christian, Sridhar Karthik, Kämmerer Peer W., and van Rienen Ursula

Subjects
electro-stimulative implants, bone defects, mandible, finite element method, Medicine
Abstract

Fractures or other major bone defects in the mandible are commonly treated by mounting a reconstruction plate at the fracture site. To avoid complications due to loosening of the implant or the fixation screws, electrical stimulation presents a possibility to accelerate bone healing. The aim of this study was to investigate different combinations of activated electrodes and plate designs regarding their feasibility for electrostimulation of the mandibular bone. The electric field distribution for multiple implant designs was computed using the finite element method. The results suggest that the electrode insulation renders a crucial parameter, which influences substantially the stimulation impact and its power consumption.

Published
2017
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45. Data_Discrimination between the effects of pulsed electrical stimulation and electrochemically conditioned medium on human osteoblasts

Author

German Research Foundation, Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Bielfeldt, Meike, Budde-Sagert, Kai, Weis, Nikolai, Buenning, Maren, Staehlke, Susanne, Zimmermann, Julius, Arbeiter, Nils, Mobini, Sahba, González Sagardoy, María Ujué, Rebl, Henrike, Uhrmacher, Adelinde, van Rienen, Ursula, Nebe, Barbara, German Research Foundation, Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Bielfeldt, Meike, Budde-Sagert, Kai, Weis, Nikolai, Buenning, Maren, Staehlke, Susanne, Zimmermann, Julius, Arbeiter, Nils, Mobini, Sahba, González Sagardoy, María Ujué, Rebl, Henrike, Uhrmacher, Adelinde, van Rienen, Ursula, and Nebe, Barbara

Abstract

This publication contains the original data supporting our results concerning the application of biphasic pulsed electrical stimulation on MG-63 cells. We aim to discriminate between effects of the electric field and electrochemically conditioned medium. The dataset consists of the original output files, excel sheets to consolidate the information for the experiments as well as Readme.txt files with most important information concerning the data. For additional information on the material and methods as well as results see the corresponding research article.

Published
2023

46. Discrimination between the effects of pulsed electrical stimulation and electrochemically conditioned medium on human osteoblasts

Author

Agencia Estatal de Investigación (España), German Research Foundation, Comunidad de Madrid, European Commission, Bielfeldt, Meike, Budde-Sagert, Kai, Weis, Nikolai, Buenning, Maren, Staehlke, Susanne, Zimmermann, Julius, Arbeiter, Nils, Mobini, Sahba, González Sagardoy, María Ujué, Rebl, Henrike, Uhrmacher, Adelinde, van Rienen, Ursula, Nebe, Barbara, Agencia Estatal de Investigación (España), German Research Foundation, Comunidad de Madrid, European Commission, Bielfeldt, Meike, Budde-Sagert, Kai, Weis, Nikolai, Buenning, Maren, Staehlke, Susanne, Zimmermann, Julius, Arbeiter, Nils, Mobini, Sahba, González Sagardoy, María Ujué, Rebl, Henrike, Uhrmacher, Adelinde, van Rienen, Ursula, and Nebe, Barbara

Abstract

Background Electrical stimulation is used for enhanced bone fracture healing. Electrochemical processes occur during the electrical stimulation at the electrodes and influence cellular reactions. Our approach aimed to distinguish between electrochemical and electric field effects on osteoblast-like MG-63 cells. We applied 20 Hz biphasic pulses via platinum electrodes for 2 h. The electrical stimulation of the cell culture medium and subsequent application to cells was compared to directly stimulated cells. The electric field distribution was predicted using a digital twin. Results Cyclic voltammetry and electrochemical impedance spectroscopy revealed partial electrolysis at the electrodes, which was confirmed by increased concentrations of hydrogen peroxide in the medium. While both direct stimulation and AC-conditioned medium decreased cell adhesion and spreading, only the direct stimulation enhanced the intracellular calcium ions and reactive oxygen species. Conclusion The electrochemical by-product hydrogen peroxide is not the main contributor to the cellular effects of electrical stimulation. However, undesired effects like decreased adhesion are mediated through electrochemical products in stimulated medium. Detailed characterisation and monitoring of the stimulation set up and electrochemical reactions are necessary to find safe electrical stimulation protocols.

Published
2023

48. Deriving Models of Cartilaginous Cells From Confocal Fluorescence Microscopy Images to Estimate Dielectric Properties

Author

Che, Vien Lam, Zimmermann, Julius, Zhou, Yilu, Lu, X. Lucas, and Van Rienen, Ursula

Abstract

The dielectric properties of cartilage are essential for the development of reliable numerical models of electrical stimulation devices intended for the regeneration of cartilage. They are, however, not widely known. To determine the dielectric properties of cartilage, we propose a numerical workflow that incorporates detailed tissue-specific 3-D geometries based on fluorescent microscopic images and describes how different parameters can affect the results. We investigated a typical bioimpedance setup that can be used for impedance sensing and electrical stimulation. The obtained results provided valuable insights that can aid in the design and implementation of future experiments, ensuring their accuracy and reliability.

Published
2024
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50. Characterization of the Electrode Tissue Interface after long-term Deep Brain Stimulation in a 6-Hydroxydopamine Hemi-Parkinson rat model

Author

Kober, Maria, primary, Bernsdorff, Felix, additional, Zimmermann, Julius, additional, Statz, Meike, additional, Lanto, Jennifer, additional, Arbeiter, Nils, additional, Bathel, Henning, additional, Payonk, Philipp, additional, Fauser, Mareike, additional, van Rienen, Ursula, additional, and Storch, Alexander, additional

Published
2023
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