--- _id: '14742' abstract: - lang: eng text: "Chromosomal rearrangements (CRs) have been known since almost the beginning of genetics.\r\nWhile an important role for CRs in speciation has been suggested, evidence primarily stems\r\nfrom theoretical and empirical studies focusing on the microevolutionary level (i.e., on taxon\r\npairs where speciation is often incomplete). Although the role of CRs in eukaryotic speciation at\r\na macroevolutionary level has been supported by associations between species diversity and\r\nrates of evolution of CRs across phylogenies, these findings are limited to a restricted range of\r\nCRs and taxa. Now that more broadly applicable and precise CR detection approaches have\r\nbecome available, we address the challenges in filling some of the conceptual and empirical\r\ngaps between micro- and macroevolutionary studies on the role of CRs in speciation. We\r\nsynthesize what is known about the macroevolutionary impact of CRs and suggest new research avenues to overcome the pitfalls of previous studies to gain a more comprehensive understanding of the evolutionary significance of CRs in speciation across the tree of life." acknowledgement: "K.L. was funded by a Swiss National Science Foundation Eccellenza project: The evolution of strong reproductive barriers towards the completion of speciation (PCEFP3_202869). R.F.\r\nwas funded by an FCT CEEC (Fundação para a Ciênca e a Tecnologia, Concurso Estímulo ao\r\nEmprego Científico) contract (2020.00275. CEECIND) and by an FCT research project\r\n(PTDC/BIA-EVL/1614/2021). M.R. was funded by the Swedish Research Council Vetenskapsrådet (grant number 2021-05243). A.M.W. was partly funded by the Norwegian Research Council RCN. We thank Luis Silva for his help preparing Figure 1. We are grateful to Maren Wellenreuther, Daniel Bolnick, and two anonymous reviewers for their constructive feedback on an earlier version of this paper." article_number: a041447 article_processing_charge: No article_type: original author: - first_name: Kay full_name: Lucek, Kay last_name: Lucek - first_name: Mabel D. full_name: Giménez, Mabel D. last_name: Giménez - first_name: Mathieu full_name: Joron, Mathieu last_name: Joron - first_name: Marina full_name: Rafajlović, Marina last_name: Rafajlović - first_name: Jeremy B. full_name: Searle, Jeremy B. last_name: Searle - first_name: Nora full_name: Walden, Nora last_name: Walden - first_name: Anja M full_name: Westram, Anja M id: 3C147470-F248-11E8-B48F-1D18A9856A87 last_name: Westram orcid: 0000-0003-1050-4969 - first_name: Rui full_name: Faria, Rui last_name: Faria citation: ama: 'Lucek K, Giménez MD, Joron M, et al. The impact of chromosomal rearrangements in speciation: From micro- to macroevolution. Cold Spring Harbor Perspectives in Biology. 2023;15(11). doi:10.1101/cshperspect.a041447' apa: 'Lucek, K., Giménez, M. D., Joron, M., Rafajlović, M., Searle, J. B., Walden, N., … Faria, R. (2023). The impact of chromosomal rearrangements in speciation: From micro- to macroevolution. Cold Spring Harbor Perspectives in Biology. Cold Spring Harbor Laboratory Press. https://doi.org/10.1101/cshperspect.a041447' chicago: 'Lucek, Kay, Mabel D. Giménez, Mathieu Joron, Marina Rafajlović, Jeremy B. Searle, Nora Walden, Anja M Westram, and Rui Faria. “The Impact of Chromosomal Rearrangements in Speciation: From Micro- to Macroevolution.” Cold Spring Harbor Perspectives in Biology. Cold Spring Harbor Laboratory Press, 2023. https://doi.org/10.1101/cshperspect.a041447.' ieee: 'K. Lucek et al., “The impact of chromosomal rearrangements in speciation: From micro- to macroevolution,” Cold Spring Harbor Perspectives in Biology, vol. 15, no. 11. Cold Spring Harbor Laboratory Press, 2023.' ista: 'Lucek K, Giménez MD, Joron M, Rafajlović M, Searle JB, Walden N, Westram AM, Faria R. 2023. The impact of chromosomal rearrangements in speciation: From micro- to macroevolution. Cold Spring Harbor Perspectives in Biology. 15(11), a041447.' mla: 'Lucek, Kay, et al. “The Impact of Chromosomal Rearrangements in Speciation: From Micro- to Macroevolution.” Cold Spring Harbor Perspectives in Biology, vol. 15, no. 11, a041447, Cold Spring Harbor Laboratory Press, 2023, doi:10.1101/cshperspect.a041447.' short: K. Lucek, M.D. Giménez, M. Joron, M. Rafajlović, J.B. Searle, N. Walden, A.M. Westram, R. Faria, Cold Spring Harbor Perspectives in Biology 15 (2023). date_created: 2024-01-08T12:43:48Z date_published: 2023-11-01T00:00:00Z date_updated: 2026-06-18T17:37:44Z day: '01' ddc: - '570' department: - _id: NiBa - _id: BeVi doi: 10.1101/cshperspect.a041447 external_id: isi: - '001096272600001' pmid: - '37604585' intvolume: ' 15' isi: 1 issue: '11' keyword: - General Biochemistry - Genetics and Molecular Biology language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1101/cshperspect.a041447 month: '11' oa: 1 oa_version: Published Version pmid: 1 publication: Cold Spring Harbor Perspectives in Biology publication_identifier: issn: - 1943-0264 publication_status: published publisher: Cold Spring Harbor Laboratory Press quality_controlled: '1' scopus_import: '1' status: public title: 'The impact of chromosomal rearrangements in speciation: From micro- to macroevolution' type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 15 year: '2023' ... --- _id: '14861' abstract: - lang: eng text: Cover Page article_number: ' e202304138' article_processing_charge: No author: - first_name: Lea Marie full_name: Becker, Lea Marie id: 36336939-eb97-11eb-a6c2-c83f1214ca79 last_name: Becker orcid: 0000-0002-6401-5151 - first_name: Mélanie full_name: Berbon, Mélanie last_name: Berbon - first_name: Alicia full_name: Vallet, Alicia last_name: Vallet - first_name: Axelle full_name: Grelard, Axelle last_name: Grelard - first_name: Estelle full_name: Morvan, Estelle last_name: Morvan - first_name: Benjamin full_name: Bardiaux, Benjamin last_name: Bardiaux - first_name: Roman full_name: Lichtenecker, Roman last_name: Lichtenecker - first_name: Matthias full_name: Ernst, Matthias last_name: Ernst - first_name: Antoine full_name: Loquet, Antoine last_name: Loquet - first_name: Paul full_name: Schanda, Paul id: 7B541462-FAF6-11E9-A490-E8DFE5697425 last_name: Schanda orcid: 0000-0002-9350-7606 citation: ama: 'Becker LM, Berbon M, Vallet A, et al. Cover Picture: The Rigid Core and Flexible Surface of Amyloid Fibrils Probed by Magic‐Angle‐Spinning NMR Spectroscopy of Aromatic Residues. Vol 62. Wiley; 2023. doi:10.1002/anie.202304138' apa: 'Becker, L. M., Berbon, M., Vallet, A., Grelard, A., Morvan, E., Bardiaux, B., … Schanda, P. (2023). Cover Picture: The rigid core and flexible surface of amyloid fibrils probed by Magic‐Angle‐Spinning NMR spectroscopy of aromatic residues. Angewandte Chemie International Edition (Vol. 62). Wiley. https://doi.org/10.1002/anie.202304138' chicago: 'Becker, Lea Marie, Mélanie Berbon, Alicia Vallet, Axelle Grelard, Estelle Morvan, Benjamin Bardiaux, Roman Lichtenecker, Matthias Ernst, Antoine Loquet, and Paul Schanda. Cover Picture: The Rigid Core and Flexible Surface of Amyloid Fibrils Probed by Magic‐Angle‐Spinning NMR Spectroscopy of Aromatic Residues. Angewandte Chemie International Edition. Vol. 62. Wiley, 2023. https://doi.org/10.1002/anie.202304138.' ieee: 'L. M. Becker et al., Cover Picture: The rigid core and flexible surface of amyloid fibrils probed by Magic‐Angle‐Spinning NMR spectroscopy of aromatic residues, vol. 62, no. 19. Wiley, 2023.' ista: 'Becker LM, Berbon M, Vallet A, Grelard A, Morvan E, Bardiaux B, Lichtenecker R, Ernst M, Loquet A, Schanda P. 2023. Cover Picture: The rigid core and flexible surface of amyloid fibrils probed by Magic‐Angle‐Spinning NMR spectroscopy of aromatic residues, Wiley,p.' mla: 'Becker, Lea Marie, et al. “Cover Picture: The Rigid Core and Flexible Surface of Amyloid Fibrils Probed by Magic‐Angle‐Spinning NMR Spectroscopy of Aromatic Residues.” Angewandte Chemie International Edition, vol. 62, no. 19, e202304138, Wiley, 2023, doi:10.1002/anie.202304138.' short: 'L.M. Becker, M. Berbon, A. Vallet, A. Grelard, E. Morvan, B. Bardiaux, R. Lichtenecker, M. Ernst, A. Loquet, P. Schanda, Cover Picture: The Rigid Core and Flexible Surface of Amyloid Fibrils Probed by Magic‐Angle‐Spinning NMR Spectroscopy of Aromatic Residues, Wiley, 2023.' corr_author: '1' date_created: 2024-01-22T11:54:34Z date_published: 2023-05-02T00:00:00Z date_updated: 2026-06-18T17:41:09Z day: '02' ddc: - '540' department: - _id: PaSc doi: 10.1002/anie.202304138 intvolume: ' 62' issue: '19' keyword: - General Chemistry - Catalysis language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1002/anie.202304138 month: '05' oa: 1 oa_version: Published Version publication: Angewandte Chemie International Edition publication_identifier: eissn: - 1521-3773 issn: - 1433-7851 publication_status: published publisher: Wiley related_material: link: - relation: translation url: https://doi.org/10.1002/ange.202304138 record: - id: '12675' relation: other status: public status: public title: 'Cover Picture: The rigid core and flexible surface of amyloid fibrils probed by Magic‐Angle‐Spinning NMR spectroscopy of aromatic residues' type: other_academic_publication user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 62 year: '2023' ... --- _id: '14773' abstract: - lang: eng text: Through a combination of idealized simulations and real-world data, researchers are uncovering how internal feedbacks and large-scale motions influence cloud dynamics. article_number: '28' article_processing_charge: No article_type: original author: - first_name: Caroline J full_name: Muller, Caroline J id: f978ccb0-3f7f-11eb-b193-b0e2bd13182b last_name: Muller orcid: 0000-0001-5836-5350 - first_name: Sophie full_name: Abramian, Sophie last_name: Abramian citation: ama: Muller CJ, Abramian S. The cloud dynamics of convective storm systems. Physics Today. 2023;76(5). doi:10.1063/pt.3.5234 apa: Muller, C. J., & Abramian, S. (2023). The cloud dynamics of convective storm systems. Physics Today. AIP Publishing. https://doi.org/10.1063/pt.3.5234 chicago: Muller, Caroline J, and Sophie Abramian. “The Cloud Dynamics of Convective Storm Systems.” Physics Today. AIP Publishing, 2023. https://doi.org/10.1063/pt.3.5234. ieee: C. J. Muller and S. Abramian, “The cloud dynamics of convective storm systems,” Physics Today, vol. 76, no. 5. AIP Publishing, 2023. ista: Muller CJ, Abramian S. 2023. The cloud dynamics of convective storm systems. Physics Today. 76(5), 28. mla: Muller, Caroline J., and Sophie Abramian. “The Cloud Dynamics of Convective Storm Systems.” Physics Today, vol. 76, no. 5, 28, AIP Publishing, 2023, doi:10.1063/pt.3.5234. short: C.J. Muller, S. Abramian, Physics Today 76 (2023). corr_author: '1' date_created: 2024-01-10T09:18:04Z date_published: 2023-05-01T00:00:00Z date_updated: 2026-06-18T17:38:37Z day: '01' ddc: - '550' department: - _id: CaMu doi: 10.1063/pt.3.5234 external_id: isi: - '000984516100007' intvolume: ' 76' isi: 1 issue: '5' keyword: - General Physics and Astronomy language: - iso: eng main_file_link: - open_access: '1' url: https://www.lmd.ens.fr/muller/Pubs/2023-MullerAbramianPhysToday.pdf month: '05' oa: 1 oa_version: Published Version publication: Physics Today publication_identifier: eissn: - 1945-0699 issn: - 0031-9228 publication_status: published publisher: AIP Publishing quality_controlled: '1' status: public title: The cloud dynamics of convective storm systems type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 76 year: '2023' ... --- _id: '14989' abstract: - lang: eng text: "Encryption alone is not enough for secure end-to end encrypted messaging: a server must also honestly serve public keys to users. Key transparency has been presented as an efficient\r\nsolution for detecting (and hence deterring) a server that attempts to dishonestly serve keys. Key transparency involves two major components: (1) a username to public key mapping, stored and cryptographically committed to by the server, and, (2) an outof-band consistency protocol for serving short commitments to users. In the setting of real-world deployments and supporting production scale, new challenges must be considered for both of these components. We enumerate these challenges and provide solutions to address them. In particular, we design and implement a memory-optimized and privacy-preserving verifiable data structure for committing to the username to public key store.\r\nTo make this implementation viable for production, we also integrate support for persistent and distributed storage. We also propose a future-facing solution, termed “compaction”, as\r\na mechanism for mitigating practical issues that arise from dealing with infinitely growing server data structures. Finally, we implement a consensusless solution that achieves the minimum requirements for a service that consistently distributes commitments for a transparency application, providing a much more efficient protocol for distributing small and consistent\r\ncommitments to users. This culminates in our production-grade implementation of a key transparency system (Parakeet) which we have open-sourced, along with a demonstration of feasibility through our benchmarks." acknowledgement: This work is supported by the Novi team at Meta and funded in part by IC3 industry partners and NSF grant 1943499. article_processing_charge: No author: - first_name: Harjasleen full_name: Malvai, Harjasleen last_name: Malvai - first_name: Eleftherios full_name: Kokoris Kogias, Eleftherios id: f5983044-d7ef-11ea-ac6d-fd1430a26d30 last_name: Kokoris Kogias orcid: 0000-0002-8827-3382 - first_name: Alberto full_name: Sonnino, Alberto last_name: Sonnino - first_name: Esha full_name: Ghosh, Esha last_name: Ghosh - first_name: Ercan full_name: Oztürk, Ercan last_name: Oztürk - first_name: Kevin full_name: Lewi, Kevin last_name: Lewi - first_name: Sean full_name: Lawlor, Sean last_name: Lawlor citation: ama: 'Malvai H, Kokoris Kogias E, Sonnino A, et al. Parakeet: Practical key transparency for end-to-end eEncrypted messaging. In: Proceedings of the 2023 Network and Distributed System Security Symposium. Internet Society; 2023. doi:10.14722/ndss.2023.24545' apa: 'Malvai, H., Kokoris Kogias, E., Sonnino, A., Ghosh, E., Oztürk, E., Lewi, K., & Lawlor, S. (2023). Parakeet: Practical key transparency for end-to-end eEncrypted messaging. In Proceedings of the 2023 Network and Distributed System Security Symposium. San Diego, CA, United States: Internet Society. https://doi.org/10.14722/ndss.2023.24545' chicago: 'Malvai, Harjasleen, Eleftherios Kokoris Kogias, Alberto Sonnino, Esha Ghosh, Ercan Oztürk, Kevin Lewi, and Sean Lawlor. “Parakeet: Practical Key Transparency for End-to-End EEncrypted Messaging.” In Proceedings of the 2023 Network and Distributed System Security Symposium. Internet Society, 2023. https://doi.org/10.14722/ndss.2023.24545.' ieee: 'H. Malvai et al., “Parakeet: Practical key transparency for end-to-end eEncrypted messaging,” in Proceedings of the 2023 Network and Distributed System Security Symposium, San Diego, CA, United States, 2023.' ista: 'Malvai H, Kokoris Kogias E, Sonnino A, Ghosh E, Oztürk E, Lewi K, Lawlor S. 2023. Parakeet: Practical key transparency for end-to-end eEncrypted messaging. Proceedings of the 2023 Network and Distributed System Security Symposium. NDSS: Network and Distributed Systems Security.' mla: 'Malvai, Harjasleen, et al. “Parakeet: Practical Key Transparency for End-to-End EEncrypted Messaging.” Proceedings of the 2023 Network and Distributed System Security Symposium, Internet Society, 2023, doi:10.14722/ndss.2023.24545.' short: H. Malvai, E. Kokoris Kogias, A. Sonnino, E. Ghosh, E. Oztürk, K. Lewi, S. Lawlor, in:, Proceedings of the 2023 Network and Distributed System Security Symposium, Internet Society, 2023. conference: end_date: 2023-03-03 location: San Diego, CA, United States name: 'NDSS: Network and Distributed Systems Security' start_date: 2023-02-27 date_created: 2024-02-14T14:20:40Z date_published: 2023-03-01T00:00:00Z date_updated: 2026-06-18T17:41:59Z day: '01' ddc: - '000' department: - _id: ElKo doi: 10.14722/ndss.2023.24545 language: - iso: eng main_file_link: - open_access: '1' url: https://eprint.iacr.org/2023/081 month: '03' oa: 1 oa_version: Published Version publication: Proceedings of the 2023 Network and Distributed System Security Symposium publication_identifier: isbn: - '1891562835' publication_status: published publisher: Internet Society quality_controlled: '1' scopus_import: '1' status: public title: 'Parakeet: Practical key transparency for end-to-end eEncrypted messaging' type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '14924' abstract: - lang: eng text: "The stochastic heavy ball method (SHB), also known as stochastic gradient descent (SGD) with Polyak's momentum, is widely used in training neural networks. However, despite the remarkable success of such algorithm in practice, its theoretical characterization remains limited. In this paper, we focus on neural networks with two and three layers and provide a rigorous understanding of the properties of the solutions found by SHB: \\emph{(i)} stability after dropping out part of the neurons, \\emph{(ii)} connectivity along a low-loss path, and \\emph{(iii)} convergence to the global optimum.\r\nTo achieve this goal, we take a mean-field view and relate the SHB dynamics to a certain partial differential equation in the limit of large network widths. This mean-field perspective has inspired a recent line of work focusing on SGD while, in contrast, our paper considers an algorithm with momentum. More specifically, after proving existence and uniqueness of the limit differential equations, we show convergence to the global optimum and give a quantitative bound between the mean-field limit and the SHB dynamics of a finite-width network. Armed with this last bound, we are able to establish the dropout-stability and connectivity of SHB solutions." acknowledgement: D. Wu and M. Mondelli are partially supported by the 2019 Lopez-Loreta Prize. V. Kungurtsev was supported by the OP VVV project CZ.02.1.01/0.0/0.0/16_019/0000765 "Research Center for Informatics". alternative_title: - TMLR article_processing_charge: No arxiv: 1 author: - first_name: Diyuan full_name: Wu, Diyuan id: 1a5914c2-896a-11ed-bdf8-fb80621a0635 last_name: Wu - first_name: Vyacheslav full_name: Kungurtsev, Vyacheslav last_name: Kungurtsev - first_name: Marco full_name: Mondelli, Marco id: 27EB676C-8706-11E9-9510-7717E6697425 last_name: Mondelli orcid: 0000-0002-3242-7020 citation: ama: 'Wu D, Kungurtsev V, Mondelli M. Mean-field analysis for heavy ball methods: Dropout-stability, connectivity, and global convergence. In: Transactions on Machine Learning Research. ML Research Press; 2023.' apa: 'Wu, D., Kungurtsev, V., & Mondelli, M. (2023). Mean-field analysis for heavy ball methods: Dropout-stability, connectivity, and global convergence. In Transactions on Machine Learning Research. ML Research Press.' chicago: 'Wu, Diyuan, Vyacheslav Kungurtsev, and Marco Mondelli. “Mean-Field Analysis for Heavy Ball Methods: Dropout-Stability, Connectivity, and Global Convergence.” In Transactions on Machine Learning Research. ML Research Press, 2023.' ieee: 'D. Wu, V. Kungurtsev, and M. Mondelli, “Mean-field analysis for heavy ball methods: Dropout-stability, connectivity, and global convergence,” in Transactions on Machine Learning Research, 2023.' ista: 'Wu D, Kungurtsev V, Mondelli M. 2023. Mean-field analysis for heavy ball methods: Dropout-stability, connectivity, and global convergence. Transactions on Machine Learning Research. , TMLR, .' mla: 'Wu, Diyuan, et al. “Mean-Field Analysis for Heavy Ball Methods: Dropout-Stability, Connectivity, and Global Convergence.” Transactions on Machine Learning Research, ML Research Press, 2023.' short: D. Wu, V. Kungurtsev, M. Mondelli, in:, Transactions on Machine Learning Research, ML Research Press, 2023. corr_author: '1' date_created: 2024-02-02T11:21:56Z date_published: 2023-02-28T00:00:00Z date_updated: 2026-06-18T17:41:36Z day: '28' ddc: - '000' department: - _id: MaMo external_id: arxiv: - '2210.06819' has_accepted_license: '1' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2210.06819 month: '02' oa: 1 oa_version: Published Version project: - _id: 059876FA-7A3F-11EA-A408-12923DDC885E name: Prix Lopez-Loretta 2019 - Marco Mondelli publication: Transactions on Machine Learning Research publication_status: published publisher: ML Research Press quality_controlled: '1' status: public title: 'Mean-field analysis for heavy ball methods: Dropout-stability, connectivity, and global convergence' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '14993' abstract: - lang: eng text: "Traditional top-down approaches for global health have historically failed to achieve social progress (Hoffman et al., 2015; Hoffman & Røttingen, 2015). Recently, however, a more holistic, multi-level approach termed One Health (OH) (Osterhaus et al., 2020) is being adopted. Several sets of challenges have been identified for the implementation of OH (dos S. Ribeiro et al., 2019), including policy and funding, education and training, and multi-actor, multi-domain, and multi-level collaborations. These exist despite the increasing accessibility to\r\nknowledge and digital collaborative research tools through the internet. To address some of these challenges, we propose a general framework for grassroots community-based means of participatory research. Additionally, we present a specific roadmap to create a Machine Learning for Global Health community in Africa. The proposed framework aims to enable any small group of individuals with scarce resources to build and sustain an online community within approximately two years. We provide a discussion on the potential impact of the proposed framework for global health research collaborations." acknowledgement: "Houcemeddine Turki’s contributions to this final output have been funded through the Adapting\r\nWikidata to support clinical practice using Data Science, Semantic Web and Machine Learning\r\nproject, which is part of the Wikimedia Research Fund maintained by the Wikimedia Foundation in San Francisco, California, United States of America." article_processing_charge: No author: - first_name: Christopher full_name: Currin, Christopher id: e8321fc5-3091-11eb-8a53-83f309a11ac9 last_name: Currin orcid: 0000-0002-4809-5059 - first_name: Mercy Nyamewaa full_name: Asiedu , Mercy Nyamewaa last_name: 'Asiedu ' - first_name: Chris full_name: Fourie, Chris last_name: Fourie - first_name: Benjamin full_name: Rosman, Benjamin last_name: Rosman - first_name: Houcemeddine full_name: Turki, Houcemeddine last_name: Turki - first_name: Atnafu full_name: Lambebo Tonja, Atnafu last_name: Lambebo Tonja - first_name: Jade full_name: Abbott, Jade last_name: Abbott - first_name: Marvellous full_name: Ajala, Marvellous last_name: Ajala - first_name: Sadiq Adewale full_name: Adedayo, Sadiq Adewale last_name: Adedayo - first_name: Chris Chinenye full_name: Emezue, Chris Chinenye last_name: Emezue - first_name: Daphne full_name: Machangara, Daphne last_name: Machangara citation: ama: 'Currin C, Asiedu MN, Fourie C, et al. A framework for grassroots research collaboration in machine learning and global health. In: 1st Workshop on Machine Learning & Global Health. OpenReview; 2023.' apa: 'Currin, C., Asiedu , M. N., Fourie, C., Rosman, B., Turki, H., Lambebo Tonja, A., … Machangara, D. (2023). A framework for grassroots research collaboration in machine learning and global health. In 1st Workshop on Machine Learning & Global Health. Kigali, Rwanda: OpenReview.' chicago: Currin, Christopher, Mercy Nyamewaa Asiedu , Chris Fourie, Benjamin Rosman, Houcemeddine Turki, Atnafu Lambebo Tonja, Jade Abbott, et al. “A Framework for Grassroots Research Collaboration in Machine Learning and Global Health.” In 1st Workshop on Machine Learning & Global Health. OpenReview, 2023. ieee: C. Currin et al., “A framework for grassroots research collaboration in machine learning and global health,” in 1st Workshop on Machine Learning & Global Health, Kigali, Rwanda, 2023. ista: 'Currin C, Asiedu MN, Fourie C, Rosman B, Turki H, Lambebo Tonja A, Abbott J, Ajala M, Adedayo SA, Emezue CC, Machangara D. 2023. A framework for grassroots research collaboration in machine learning and global health. 1st Workshop on Machine Learning & Global Health. ICLR: International Conference on Learning Representations.' mla: Currin, Christopher, et al. “A Framework for Grassroots Research Collaboration in Machine Learning and Global Health.” 1st Workshop on Machine Learning & Global Health, OpenReview, 2023. short: C. Currin, M.N. Asiedu , C. Fourie, B. Rosman, H. Turki, A. Lambebo Tonja, J. Abbott, M. Ajala, S.A. Adedayo, C.C. Emezue, D. Machangara, in:, 1st Workshop on Machine Learning & Global Health, OpenReview, 2023. conference: end_date: 2023-05-05 location: Kigali, Rwanda name: 'ICLR: International Conference on Learning Representations' start_date: 2023-05-05 date_created: 2024-02-14T15:11:48Z date_published: 2023-03-02T00:00:00Z date_updated: 2026-06-18T17:42:25Z day: '02' ddc: - '000' department: - _id: TiVo language: - iso: eng main_file_link: - open_access: '1' url: https://openreview.net/forum?id=jHY_G91R880 month: '03' oa: 1 oa_version: Published Version publication: 1st Workshop on Machine Learning & Global Health publication_status: published publisher: OpenReview quality_controlled: '1' status: public title: A framework for grassroots research collaboration in machine learning and global health type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '14759' abstract: - lang: eng text: "Proper operation of electro-optic I/Q modulators relies on precise adjustment and control of the relative phase biases between the modulator’s internal interferometer arms. We present an all-analog phase bias locking scheme where error signals are obtained from the beat between the optical carrier and optical tones generated by an auxiliary 2 MHz \U0001D445\U0001D439 tone to lock the phases of all three involved interferometers for operation up to 10 GHz. With the developed method, we demonstrate an I/Q modulator in carrier-suppressed single-sideband mode, where the suppressed carrier and sideband are locked at optical power levels <−27dB\r\n relative to the transmitted sideband. We describe a simple analytical model for calculating the error signals and detail the implementation of the electronic circuitry for the implementation of the method." acknowledgement: We thank Jakob Vorlaufer for technical contributions and Vyacheslav Li and Sofia Agafonova for comments on the manuscript. article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Sebastian full_name: Wald, Sebastian id: 133F200A-B015-11E9-AD41-0EDAE5697425 last_name: Wald orcid: 0000-0002-5869-1604 - first_name: Fritz R full_name: Diorico, Fritz R id: 2E054C4C-F248-11E8-B48F-1D18A9856A87 last_name: Diorico orcid: 0000-0002-4947-8924 - first_name: Onur full_name: Hosten, Onur id: 4C02D85E-F248-11E8-B48F-1D18A9856A87 last_name: Hosten orcid: 0000-0002-2031-204X citation: ama: Wald S, Diorico FR, Hosten O. Analog stabilization of an electro-optic I/Q modulator with an auxiliary modulation tone. Applied Optics. 2023;62(1):1-7. doi:10.1364/ao.474118 apa: Wald, S., Diorico, F. R., & Hosten, O. (2023). Analog stabilization of an electro-optic I/Q modulator with an auxiliary modulation tone. Applied Optics. Optica Publishing Group. https://doi.org/10.1364/ao.474118 chicago: Wald, Sebastian, Fritz R Diorico, and Onur Hosten. “Analog Stabilization of an Electro-Optic I/Q Modulator with an Auxiliary Modulation Tone.” Applied Optics. Optica Publishing Group, 2023. https://doi.org/10.1364/ao.474118. ieee: S. Wald, F. R. Diorico, and O. Hosten, “Analog stabilization of an electro-optic I/Q modulator with an auxiliary modulation tone,” Applied Optics, vol. 62, no. 1. Optica Publishing Group, pp. 1–7, 2023. ista: Wald S, Diorico FR, Hosten O. 2023. Analog stabilization of an electro-optic I/Q modulator with an auxiliary modulation tone. Applied Optics. 62(1), 1–7. mla: Wald, Sebastian, et al. “Analog Stabilization of an Electro-Optic I/Q Modulator with an Auxiliary Modulation Tone.” Applied Optics, vol. 62, no. 1, Optica Publishing Group, 2023, pp. 1–7, doi:10.1364/ao.474118. short: S. Wald, F.R. Diorico, O. Hosten, Applied Optics 62 (2023) 1–7. corr_author: '1' date_created: 2024-01-08T13:19:14Z date_published: 2023-01-01T00:00:00Z date_updated: 2026-06-18T22:30:04Z day: '01' department: - _id: OnHo doi: 10.1364/ao.474118 external_id: arxiv: - '2208.11591' isi: - '000906607900001' intvolume: ' 62' isi: 1 issue: '1' keyword: - Atomic and Molecular Physics - and Optics - Engineering (miscellaneous) - Electrical and Electronic Engineering language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2208.11591 month: '01' oa: 1 oa_version: Preprint page: 1-7 publication: Applied Optics publication_identifier: eissn: - 2155-3165 issn: - 1559-128X publication_status: published publisher: Optica Publishing Group quality_controlled: '1' related_material: record: - id: '20798' relation: dissertation_contains status: public scopus_import: '1' status: public title: Analog stabilization of an electro-optic I/Q modulator with an auxiliary modulation tone type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 62 year: '2023' ... --- OA_place: publisher _id: '12491' abstract: - lang: eng text: "The extracellular matrix (ECM) is a hydrated and complex three-dimensional network consisting of proteins, polysaccharides, and water. It provides structural scaffolding for the cells embedded within it and is essential in regulating numerous physiological processes, including cell migration and proliferation, wound healing, and stem cell fate. \r\nDespite extensive study, detailed structural knowledge of ECM components in physiologically relevant conditions is still rudimentary. This is due to methodological limitations in specimen preparation protocols which are incompatible with keeping large samples, such as the ECM, in their native state for subsequent imaging. Conventional electron microscopy (EM) techniques rely on fixation, dehydration, contrasting, and sectioning. This results in the alteration of a highly hydrated environment and the potential introduction of artifacts. Other structural biology techniques, such as nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography, allow high-resolution analysis of protein structures but only work on homogenous and purified samples, hence lacking contextual information. Currently, no approach exists for the ultrastructural and structural study of extracellular components under native conditions in a physiological, 3D environment. \r\nIn this thesis, I have developed a workflow that allows for the ultrastructural analysis of the ECM in near-native conditions at molecular resolution. The developments I introduced include implementing a novel specimen preparation workflow for cell-derived matrices (CDMs) to render them compatible with ion-beam milling and subsequent high-resolution cryo-electron tomography (ET). \r\nTo this end, I have established protocols to generate CDMs grown over several weeks on EM grids that are compatible with downstream cryo-EM sample preparation and imaging techniques. Characterization of these ECMs confirmed that they contain essential ECM components such as collagen I, collagen VI, and fibronectin I in high abundance and hence represent a bona fide biologically-relevant sample. I successfully optimized vitrification of these specimens by testing various vitrification techniques and cryoprotectants. \r\nIn order to obtain high-resolution molecular insights into the ultrastructure and organization of CDMs, I established cryo-focused ion beam scanning electron microscopy (FIBSEM) on these challenging and complex specimens. I explored different approaches for the creation of thin cryo-lamellae by FIB milling and succeeded in optimizing the cryo-lift-out technique, resulting in high-quality lamellae of approximately 200 nm thickness. \r\nHigh-resolution Cryo-ET of these lamellae revealed for the first time the architecture of native CDM in the context of matrix-secreting cells. This allowed for the in situ visualization of fibrillar matrix proteins such as collagen, laying the foundation for future structural and ultrastructural characterization of these proteins in their near-native environment. \r\nIn summary, in this thesis, I present a novel workflow that combines state-of-the-art cryo-EM specimen preparation and imaging technologies to permit characterization of the ECM, an important tissue component in higher organisms. This innovative and highly versatile workflow will enable addressing far-reaching questions on ECM architecture, composition, and reciprocal ECM-cell interactions." acknowledged_ssus: - _id: EM-Fac - _id: LifeSc - _id: Bio alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Bettina full_name: Zens, Bettina id: 45FD126C-F248-11E8-B48F-1D18A9856A87 last_name: Zens orcid: 0000-0002-9561-1239 citation: ama: Zens B. Ultrastructural characterization of natively preserved extracellular matrix by cryo-electron tomography. 2023. doi:10.15479/at:ista:12491 apa: Zens, B. (2023). Ultrastructural characterization of natively preserved extracellular matrix by cryo-electron tomography. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12491 chicago: Zens, Bettina. “Ultrastructural Characterization of Natively Preserved Extracellular Matrix by Cryo-Electron Tomography.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12491. ieee: B. Zens, “Ultrastructural characterization of natively preserved extracellular matrix by cryo-electron tomography,” Institute of Science and Technology Austria, 2023. ista: Zens B. 2023. Ultrastructural characterization of natively preserved extracellular matrix by cryo-electron tomography. Institute of Science and Technology Austria. mla: Zens, Bettina. Ultrastructural Characterization of Natively Preserved Extracellular Matrix by Cryo-Electron Tomography. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12491. short: B. Zens, Ultrastructural Characterization of Natively Preserved Extracellular Matrix by Cryo-Electron Tomography, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-02-02T14:50:20Z date_published: 2023-02-02T00:00:00Z date_updated: 2026-04-07T13:49:23Z day: '02' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: FlSc doi: 10.15479/at:ista:12491 file: - access_level: open_access checksum: 069d87f025e0799bf9e3c375664264f2 content_type: application/pdf creator: bzens date_created: 2023-02-07T13:07:38Z date_updated: 2024-02-08T23:30:04Z embargo: 2024-02-07 file_id: '12527' file_name: PhDThesis_BettinaZens_2023_final.pdf file_size: 23082464 relation: main_file - access_level: closed checksum: 8c66ed203495d6e078ed1002a866520c content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: bzens date_created: 2023-02-07T13:09:05Z date_updated: 2024-02-08T23:30:04Z embargo_to: open_access file_id: '12528' file_name: PhDThesis_BettinaZens_2023_final.docx file_size: 106169509 relation: source_file file_date_updated: 2024-02-08T23:30:04Z has_accepted_license: '1' keyword: - cryo-EM - cryo-ET - FIB milling - method development - FIBSEM - extracellular matrix - ECM - cell-derived matrices - CDMs - cell culture - high pressure freezing - HPF - structural biology - tomography - collagen language: - iso: eng month: '02' oa: 1 oa_version: Published Version page: '187' project: - _id: eba3b5f6-77a9-11ec-83b8-cf0905748aa3 name: Integrated visual proteomics of reciprocal cell-extracellular matrix interactions - _id: 059B463C-7A3F-11EA-A408-12923DDC885E name: "NÃ\x96-Fonds Preis für die Jungforscherin des Jahres am IST Austria" publication_identifier: isbn: - 978-3-99078-027-5 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '8586' relation: part_of_dissertation status: public status: public supervisor: - first_name: Florian KM full_name: Schur, Florian KM id: 48AD8942-F248-11E8-B48F-1D18A9856A87 last_name: Schur orcid: 0000-0003-4790-8078 title: Ultrastructural characterization of natively preserved extracellular matrix by cryo-electron tomography type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- OA_place: publisher _id: '13984' abstract: - lang: eng text: "Social insects fight disease using their individual immune systems and the cooperative\r\nsanitary behaviors of colony members. These social defenses are well explored against\r\nexternally-infecting pathogens, but little is known about defense strategies against\r\ninternally-infecting pathogens, such as viruses. Viruses are ubiquitous and in the last decades\r\nit has become evident that also many ant species harbor viruses. We present one of the first\r\nstudies addressing transmission dynamics and collective disease defenses against viruses in\r\nants on a mechanistic level. I successfully established an experimental ant host – viral\r\npathogen system as a model for the defense strategies used by social insects against internal\r\npathogen infections, as outlined in the third chapter. In particular, we studied how garden ants\r\n(Lasius neglectus) defend themselves and their colonies against the generalist insect virus\r\nCrPV (cricket paralysis virus). We chose microinjections of virus directly into the ants’\r\nhemolymph because it allowed us to use a defined exposure dose. Here we show that this is a\r\ngood model system, as the virus is replicating and thus infecting the host. The ants mount a\r\nclear individual immune response against the viral infection, which is characterized by a\r\nspecific siRNA pattern, namely siRNAs mapping against the viral genome with a peak of 21\r\nand 22 bp long fragments. The onset of this immune response is consistent with the timeline\r\nof viral replication that starts already within two days post injection. The disease manifests in\r\ndecreased survival over a course of two to three weeks.\r\nRegarding group living, we find that infected ants show a strong individual immune response,\r\nbut that their course of disease is little affected by nestmate presence, as described in chapter\r\nfour. Hence, we do not find social immunity in the context of viral infections in ants.\r\nNestmates, however, can contract the virus. Using Drosophila S2R+ cells in culture, we\r\nshowed that 94 % of the nestmates contract active virus within four days of social contact to\r\nan infected individual. Virus is transmitted in low doses, thus not causing disease\r\ntransmission within the colony. While virus can be transmitted during short direct contacts,\r\nwe also assume transmission from deceased ants and show that the nestmates’ immune\r\nsystem gets activated after contracting a low viral dose. We find considerable potential for\r\nindirect transmission via the nest space. Virus is shed to the nest, where it stays viable for one\r\nweek and is also picked up by other ants. Apart from that, we want to underline the potential\r\nof ant poison as antiviral agent. We determined that ant poison successfully inactivates CrPV\r\nin vitro. However, we found no evidence for effective poison use to sanitize the nest space.\r\nOn the other hand, local application of ant poison by oral poison uptake, which is part of the\r\nants prophylactic behavioral repertoire, probably contributes to keeping the gut of each\r\nindividual sanitized. We hypothesize that oral poison uptake might be the reason why we did\r\nnot find viable virus in the trophallactic fluid.\r\nThe fifth chapter encompasses preliminary data on potential social immunization. However,\r\nour experiments do not confirm an actual survival benefit for the nestmates upon pathogen\r\nchallenge under the given experimental settings. Nevertheless, we do not want to rule out the\r\npossibility for nestmate immunization, but rather emphasize that considering different\r\nexperimental timelines and viral doses would provide a multitude of options for follow-up\r\nexperiments.\r\nIn conclusion, we find that prophylactic individual behaviors, such as oral poison uptake,\r\nmight play a role in preventing viral disease transmission. Compared to colony defense\r\nagainst external pathogens, internal pathogen infections require a stronger component of\r\nindividual physiological immunity than behavioral social immunity, yet could still lead to\r\ncollective protection." acknowledged_ssus: - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Anna full_name: Franschitz, Anna id: 480826C8-F248-11E8-B48F-1D18A9856A87 last_name: Franschitz citation: ama: Franschitz A. Individual and social immunity against viral infections in ants. 2023. doi:10.15479/at:ista:13984 apa: Franschitz, A. (2023). Individual and social immunity against viral infections in ants. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:13984 chicago: Franschitz, Anna. “Individual and Social Immunity against Viral Infections in Ants.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:13984. ieee: A. Franschitz, “Individual and social immunity against viral infections in ants,” Institute of Science and Technology Austria, 2023. ista: Franschitz A. 2023. Individual and social immunity against viral infections in ants. Institute of Science and Technology Austria. mla: Franschitz, Anna. Individual and Social Immunity against Viral Infections in Ants. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:13984. short: A. Franschitz, Individual and Social Immunity against Viral Infections in Ants, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-08-08T15:33:29Z date_published: 2023-08-08T00:00:00Z date_updated: 2026-04-07T13:51:29Z day: '08' ddc: - '570' - '577' degree_awarded: PhD department: - _id: GradSch - _id: SyCr doi: 10.15479/at:ista:13984 file: - access_level: open_access checksum: 55c876b73d49db15228a7f571592ec77 content_type: application/pdf creator: cchlebak date_created: 2024-03-01T08:56:06Z date_updated: 2024-10-29T23:31:04Z embargo_to: open_access file_id: '15044' file_name: Print_Version_Franschitz_Anna_Thesis.pdf file_size: 10416761 relation: main_file title: Combined Version of original Thesis and Addendum - access_level: open_access checksum: 27220243d5d51c3b0d7d61c0879d7a0c content_type: application/pdf creator: afransch date_created: 2023-08-08T18:01:28Z date_updated: 2024-08-09T22:30:03Z embargo: 2024-08-08 file_id: '13986' file_name: Thesis_AnnaFranschitz_202308.pdf file_size: 10797612 relation: main_file - access_level: closed checksum: 40abf7ccca14a3893f72dc7fb88585d6 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: afransch date_created: 2023-08-08T18:02:25Z date_updated: 2024-08-09T22:30:03Z embargo_to: open_access file_id: '13987' file_name: Thesis_AnnaFranschitz_202308.docx file_size: 2619085 relation: source_file - access_level: open_access checksum: 8b991ecc2d59d045cc3cf0d676785ec7 content_type: application/pdf creator: cchlebak date_created: 2024-03-01T08:37:15Z date_updated: 2024-10-29T23:31:04Z description: Minor modifications and clarifications - Feb 2024 embargo: 2024-08-08 file_id: '15042' file_name: Addendum_AnnaFranschitz202402.pdf file_size: 85956 relation: main_file title: Addendum - access_level: closed checksum: 66745aa01f960f17472c024875c049ed content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2024-03-01T08:39:20Z date_updated: 2024-08-09T22:30:03Z embargo_to: open_access file_id: '15043' file_name: Addendum_AnnaFranschitz202402.docx file_size: 11818 relation: source_file title: Addendum - source file file_date_updated: 2024-10-29T23:31:04Z has_accepted_license: '1' language: - iso: eng month: '08' oa: 1 oa_version: Published Version page: '89' publication_identifier: isbn: - 978-3-99078-034-3 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Sylvia full_name: Cremer, Sylvia id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87 last_name: Cremer orcid: 0000-0002-2193-3868 title: Individual and social immunity against viral infections in ants type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '12897' abstract: - lang: eng text: "Inverse design problems in fabrication-aware shape optimization are typically solved on discrete representations such as polygonal meshes. This thesis argues that there are benefits to treating these problems in the same domain as human designers, namely, the parametric one. One reason is that discretizing a parametric model usually removes the capability of making further manual changes to the design, because the human intent is captured by the shape parameters. Beyond this, knowledge about a design problem can sometimes reveal a structure that is present in a smooth representation, but is fundamentally altered by discretizing. In this case, working in the parametric domain may even simplify the optimization task. We present two lines of research that explore both of these aspects of fabrication-aware shape optimization on parametric representations.\r\n\r\nThe first project studies the design of plane elastic curves and Kirchhoff rods, which are common mathematical models for describing the deformation of thin elastic rods such as beams, ribbons, cables, and hair. Our main contribution is a characterization of all curved shapes that can be attained by bending and twisting elastic rods having a stiffness that is allowed to vary across the length. Elements like these can be manufactured using digital fabrication devices such as 3d printers and digital cutters, and have applications in free-form architecture and soft robotics.\r\n\r\nWe show that the family of curved shapes that can be produced this way admits geometric description that is concise and computationally convenient. In the case of plane curves, the geometric description is intuitive enough to allow a designer to determine whether a curved shape is physically achievable by visual inspection alone. We also present shape optimization algorithms that convert a user-defined curve in the plane or in three dimensions into the geometry of an elastic rod that will naturally deform to follow this curve when its endpoints are attached to a support structure. Implemented in an interactive software design tool, the rod geometry is generated in real time as the user edits a curve and enables fast prototyping. \r\n\r\nThe second project tackles the problem of general-purpose shape optimization on CAD models using a novel variant of the extended finite element method (XFEM). Our goal is the decoupling between the simulation mesh and the CAD model, so no geometry-dependent meshing or remeshing needs to be performed when the CAD parameters change during optimization. This is achieved by discretizing the embedding space of the CAD model, and using a new high-accuracy numerical integration method to enable XFEM on free-form elements bounded by the parametric surface patches of the model. Our simulation is differentiable from the CAD parameters to the simulation output, which enables us to use off-the-shelf gradient-based optimization procedures. The result is a method that fits seamlessly into the CAD workflow because it works on the same representation as the designer, enabling the alternation of manual editing and fabrication-aware optimization at will." acknowledged_ssus: - _id: M-Shop alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Christian full_name: Hafner, Christian id: 400429CC-F248-11E8-B48F-1D18A9856A87 last_name: Hafner citation: ama: 'Hafner C. Inverse shape design with parametric representations: Kirchhoff Rods and parametric surface models. 2023. doi:10.15479/at:ista:12897' apa: 'Hafner, C. (2023). Inverse shape design with parametric representations: Kirchhoff Rods and parametric surface models. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12897' chicago: 'Hafner, Christian. “Inverse Shape Design with Parametric Representations: Kirchhoff Rods and Parametric Surface Models.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12897.' ieee: 'C. Hafner, “Inverse shape design with parametric representations: Kirchhoff Rods and parametric surface models,” Institute of Science and Technology Austria, 2023.' ista: 'Hafner C. 2023. Inverse shape design with parametric representations: Kirchhoff Rods and parametric surface models. Institute of Science and Technology Austria.' mla: 'Hafner, Christian. Inverse Shape Design with Parametric Representations: Kirchhoff Rods and Parametric Surface Models. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12897.' short: 'C. Hafner, Inverse Shape Design with Parametric Representations: Kirchhoff Rods and Parametric Surface Models, Institute of Science and Technology Austria, 2023.' corr_author: '1' date_created: 2023-05-05T10:40:14Z date_published: 2023-05-05T00:00:00Z date_updated: 2025-04-15T07:16:15Z day: '05' ddc: - '516' - '004' - '518' - '531' degree_awarded: PhD department: - _id: GradSch - _id: BeBi doi: 10.15479/at:ista:12897 ec_funded: 1 file: - access_level: open_access checksum: cc2094e92fa27000b70eb4bfb76d6b5a content_type: application/pdf creator: chafner date_created: 2023-05-11T10:43:20Z date_updated: 2023-12-08T23:30:04Z embargo: 2023-12-07 file_id: '12942' file_name: thesis-hafner-2023may11-a2b.pdf file_size: 50714445 relation: main_file - access_level: closed checksum: a6b51334be2b81672357b1549afab40c content_type: application/pdf creator: chafner date_created: 2023-05-11T10:43:44Z date_updated: 2023-12-08T23:30:04Z embargo_to: open_access file_id: '12943' file_name: thesis-release-form.pdf file_size: 265319 relation: source_file file_date_updated: 2023-12-08T23:30:04Z has_accepted_license: '1' language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '180' project: - _id: 24F9549A-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '715767' name: 'MATERIALIZABLE: Intelligent fabrication-oriented Computational Design and Modeling' publication_identifier: isbn: - 978-3-99078-031-2 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '9817' relation: part_of_dissertation status: public - id: '13188' relation: dissertation_contains status: public - id: '7117' relation: part_of_dissertation status: public status: public supervisor: - first_name: Bernd full_name: Bickel, Bernd id: 49876194-F248-11E8-B48F-1D18A9856A87 last_name: Bickel orcid: 0000-0001-6511-9385 title: 'Inverse shape design with parametric representations: Kirchhoff Rods and parametric surface models' type: dissertation user_id: 400429CC-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '13188' abstract: - lang: eng text: "The Kirchhoff rod model describes the bending and twisting of slender elastic rods in three dimensions, and has been widely studied to enable the prediction of how a rod will deform, given its geometry and boundary conditions. In this work, we study a number of inverse problems with the goal of computing the geometry of a straight rod that will automatically deform to match a curved target shape after attaching its endpoints to a support structure. Our solution lets us finely control the static equilibrium state of a rod by varying the cross-sectional profiles along its length.\r\nWe also show that the set of physically realizable equilibrium states admits a concise geometric description in terms of linear line complexes, which leads to very efficient computational design algorithms. Implemented in an interactive software tool, they allow us to convert three-dimensional hand-drawn spline curves to elastic rods, and give feedback about the feasibility and practicality of a design in real time. We demonstrate the efficacy of our method by designing and manufacturing several physical prototypes with applications to interior design and soft robotics." acknowledged_ssus: - _id: M-Shop acknowledgement: We thank the anonymous reviewers for their generous feedback, and Julian Fischer for his help in proving Proposition 1. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 715767). article_number: '171' article_processing_charge: No article_type: original author: - first_name: Christian full_name: Hafner, Christian id: 400429CC-F248-11E8-B48F-1D18A9856A87 last_name: Hafner - first_name: Bernd full_name: Bickel, Bernd id: 49876194-F248-11E8-B48F-1D18A9856A87 last_name: Bickel orcid: 0000-0001-6511-9385 citation: ama: Hafner C, Bickel B. The design space of Kirchhoff rods. ACM Transactions on Graphics. 2023;42(5). doi:10.1145/3606033 apa: Hafner, C., & Bickel, B. (2023). The design space of Kirchhoff rods. ACM Transactions on Graphics. Association for Computing Machinery. https://doi.org/10.1145/3606033 chicago: Hafner, Christian, and Bernd Bickel. “The Design Space of Kirchhoff Rods.” ACM Transactions on Graphics. Association for Computing Machinery, 2023. https://doi.org/10.1145/3606033. ieee: C. Hafner and B. Bickel, “The design space of Kirchhoff rods,” ACM Transactions on Graphics, vol. 42, no. 5. Association for Computing Machinery, 2023. ista: Hafner C, Bickel B. 2023. The design space of Kirchhoff rods. ACM Transactions on Graphics. 42(5), 171. mla: Hafner, Christian, and Bernd Bickel. “The Design Space of Kirchhoff Rods.” ACM Transactions on Graphics, vol. 42, no. 5, 171, Association for Computing Machinery, 2023, doi:10.1145/3606033. short: C. Hafner, B. Bickel, ACM Transactions on Graphics 42 (2023). corr_author: '1' date_created: 2023-07-04T07:41:30Z date_published: 2023-09-20T00:00:00Z date_updated: 2026-06-18T22:30:05Z day: '20' ddc: - '516' department: - _id: BeBi doi: 10.1145/3606033 ec_funded: 1 external_id: isi: - '001086833300010' file: - access_level: open_access checksum: 4954c1cfa487725bc156dcfec872478a content_type: application/pdf creator: chafner date_created: 2023-07-04T08:11:28Z date_updated: 2023-07-04T08:11:28Z file_id: '13194' file_name: kirchhoff-rods.pdf file_size: 19635168 relation: main_file success: 1 - access_level: open_access checksum: 79c9975fbc82ff71f1767331d2204cca content_type: application/pdf creator: chafner date_created: 2023-07-04T07:46:28Z date_updated: 2023-07-04T07:46:28Z file_id: '13190' file_name: supp-main.pdf file_size: 420909 relation: supplementary_material title: Supplemental Material with Proofs - access_level: open_access checksum: 4ab647e4f03c711e1e6a5fc1eb8684db content_type: application/pdf creator: chafner date_created: 2023-07-04T07:46:30Z date_updated: 2023-07-04T07:46:30Z file_id: '13191' file_name: supp-cheat.pdf file_size: 430086 relation: supplementary_material title: Cheat Sheet for Notation - access_level: open_access checksum: c0fd9a57d012046de90c185ffa904b76 content_type: video/mp4 creator: chafner date_created: 2023-07-04T07:46:39Z date_updated: 2023-07-04T07:46:39Z file_id: '13192' file_name: kirchhoff-video-final.mp4 file_size: 268088064 relation: supplementary_material title: Supplemental Video - access_level: open_access checksum: 71b00712b489ada2cd9815910ee180a9 content_type: application/x-zip-compressed creator: chafner date_created: 2023-07-04T07:47:10Z date_updated: 2023-07-04T07:47:10Z file_id: '13193' file_name: matlab-submission.zip file_size: 25790 relation: supplementary_material title: Matlab Source Code with Example file_date_updated: 2023-07-04T08:11:28Z has_accepted_license: '1' intvolume: ' 42' isi: 1 issue: '5' keyword: - Computer Graphics - Computational Design - Computational Geometry - Shape Modeling language: - iso: eng month: '09' oa: 1 oa_version: Submitted Version project: - _id: 24F9549A-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '715767' name: 'MATERIALIZABLE: Intelligent fabrication-oriented Computational Design and Modeling' publication: ACM Transactions on Graphics publication_identifier: eissn: - 1557-7368 issn: - 0730-0301 publication_status: published publisher: Association for Computing Machinery quality_controlled: '1' related_material: record: - id: '12897' relation: part_of_dissertation status: public scopus_import: '1' status: public title: The design space of Kirchhoff rods type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 42 year: '2023' ... --- OA_place: publisher _id: '12964' abstract: - lang: eng text: "Pattern formation is of great importance for its contribution across different biological behaviours. During developmental processes for example, patterns of chemical gradients are\r\nestablished to determine cell fate and complex tissue patterns emerge to define structures such\r\nas limbs and vascular networks. Patterns are also seen in collectively migrating groups, for\r\ninstance traveling waves of density emerging in moving animal flocks as well as collectively migrating cells and tissues. To what extent these biological patterns arise spontaneously through\r\nthe local interaction of individual constituents or are dictated by higher level instructions is\r\nstill an open question however there is evidence for the involvement of both types of process.\r\nWhere patterns arise spontaneously there is a long standing interest in how far the interplay\r\nof mechanics, e.g. force generation and deformation, and chemistry, e.g. gene regulation\r\nand signaling, contributes to the behaviour. This is because many systems are able to both\r\nchemically regulate mechanical force production and chemically sense mechanical deformation,\r\nforming mechano-chemical feedback loops which can potentially become unstable towards\r\nspatio and/or temporal patterning.\r\nWe work with experimental collaborators to investigate the possibility that this type of\r\ninteraction drives pattern formation in biological systems at different scales. We focus first on\r\ntissue-level ERK-density waves observed during the wound healing response across different\r\nsystems where many previous studies have proposed that patterns depend on polarized cell\r\nmigration and arise from a mechanical flocking-like mechanism. By combining theory with\r\nmechanical and optogenetic perturbation experiments on in vitro monolayers we instead find\r\nevidence for mechanochemical pattern formation involving only scalar bilateral feedbacks\r\nbetween ERK signaling and cell contraction. We perform further modeling and experiment\r\nto study how this instability couples with polar cell migration in order to produce a robust\r\nand efficient wound healing response. In a following chapter we implement ERK-density\r\ncoupling and cell migration in a 2D active vertex model to investigate the interaction of\r\nERK-density patterning with different tissue rheologies and find that the spatio-temporal\r\ndynamics are able to both locally and globally fluidize a tissue across the solid-fluid glass\r\ntransition. In a last chapter we move towards lower spatial scales in the context of subcellular\r\npatterning of the cell cytoskeleton where we investigate the transition between phases of\r\nspatially homogeneous temporal oscillations and chaotic spatio-temporal patterning in the\r\ndynamics of myosin and ROCK activities (a motor component of the actomyosin cytoskeleton\r\nand its activator). Experimental evidence supports an intrinsic chemical oscillator which we\r\nencode in a reaction model and couple to a contractile active gel description of the cell cortex.\r\nThe model exhibits phases of chemical oscillations and contractile spatial patterning which\r\nreproduce many features of the dynamics seen in Drosophila oocyte epithelia in vivo. However,\r\nadditional pharmacological perturbations to inhibit myosin contractility leaves the role of\r\ncontractile instability unclear. We discuss alternative hypotheses and investigate the possibility\r\nof reaction-diffusion instability." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Daniel R full_name: Boocock, Daniel R id: 453AF628-F248-11E8-B48F-1D18A9856A87 last_name: Boocock orcid: 0000-0002-1585-2631 citation: ama: Boocock DR. Mechanochemical pattern formation across biological scales. 2023. doi:10.15479/at:ista:12964 apa: Boocock, D. R. (2023). Mechanochemical pattern formation across biological scales. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12964 chicago: Boocock, Daniel R. “Mechanochemical Pattern Formation across Biological Scales.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12964. ieee: D. R. Boocock, “Mechanochemical pattern formation across biological scales,” Institute of Science and Technology Austria, 2023. ista: Boocock DR. 2023. Mechanochemical pattern formation across biological scales. Institute of Science and Technology Austria. mla: Boocock, Daniel R. Mechanochemical Pattern Formation across Biological Scales. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12964. short: D.R. Boocock, Mechanochemical Pattern Formation across Biological Scales, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-05-15T14:52:36Z date_published: 2023-05-17T00:00:00Z date_updated: 2026-04-07T13:52:57Z day: '17' ddc: - '530' degree_awarded: PhD department: - _id: GradSch - _id: EdHa doi: 10.15479/at:ista:12964 ec_funded: 1 file: - access_level: open_access checksum: d51240675fc6dc0e3f5dc0c902695d3a content_type: application/pdf creator: dboocock date_created: 2023-05-17T13:39:54Z date_updated: 2024-05-18T22:30:03Z embargo: 2024-05-17 file_id: '12988' file_name: thesis_boocock.pdf file_size: 40414730 relation: main_file - access_level: closed checksum: 581a2313ffeb40fe77e8a122a25a7795 content_type: application/zip creator: dboocock date_created: 2023-05-17T13:39:53Z date_updated: 2024-05-18T22:30:03Z embargo_to: open_access file_id: '12989' file_name: thesis_boocock.zip file_size: 34338567 relation: source_file file_date_updated: 2024-05-18T22:30:03Z has_accepted_license: '1' language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '146' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-032-9 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '8602' relation: part_of_dissertation status: public status: public supervisor: - first_name: Edouard B full_name: Hannezo, Edouard B id: 3A9DB764-F248-11E8-B48F-1D18A9856A87 last_name: Hannezo orcid: 0000-0001-6005-1561 title: Mechanochemical pattern formation across biological scales tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- OA_place: publisher _id: '12809' abstract: - lang: eng text: "Understanding the mechanisms of learning and memory formation has always been one of\r\nthe main goals in neuroscience. Already Pavlov (1927) in his early days has used his classic\r\nconditioning experiments to study the neural mechanisms governing behavioral adaptation.\r\nWhat was not known back then was that the part of the brain that is largely responsible for\r\nthis type of associative learning is the cerebellum.\r\nSince then, plenty of theories on cerebellar learning have emerged. Despite their differences,\r\none thing they all have in common is that learning relies on synaptic and intrinsic plasticity.\r\nThe goal of my PhD project was to unravel the molecular mechanisms underlying synaptic\r\nplasticity in two synapses that have been shown to be implicated in motor learning, in an\r\neffort to understand how learning and memory formation are processed in the cerebellum.\r\nOne of the earliest and most well-known cerebellar theories postulates that motor learning\r\nlargely depends on long-term depression at the parallel fiber-Purkinje cell (PC-PC) synapse.\r\nHowever, the discovery of other types of plasticity in the cerebellar circuitry, like long-term\r\npotentiation (LTP) at the PC-PC synapse, potentiation of molecular layer interneurons (MLIs),\r\nand plasticity transfer from the cortex to the cerebellar/ vestibular nuclei has increased the\r\npopularity of the idea that multiple sites of plasticity might be involved in learning.\r\nStill a lot remains unknown about the molecular mechanisms responsible for these types of\r\nplasticity and whether they occur during physiological learning.\r\nIn the first part of this thesis we have analyzed the variation and nanodistribution of voltagegated calcium channels (VGCCs) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid\r\ntype glutamate receptors (AMPARs) on the parallel fiber-Purkinje cell synapse after vestibuloocular reflex phase reversal adaptation, a behavior that has been suggested to rely on PF-PC\r\nLTP. We have found that on the last day of adaptation there is no learning trace in form of\r\nVGCCs nor AMPARs variation at the PF-PC synapse, but instead a decrease in the number of\r\nPF-PC synapses. These data seem to support the view that learning is only stored in the\r\ncerebellar cortex in an initial learning phase, being transferred later to the vestibular nuclei.\r\nNext, we have studied the role of MLIs in motor learning using a relatively simple and well characterized behavioral paradigm – horizontal optokinetic reflex (HOKR) adaptation. We\r\nhave found behavior-induced MLI potentiation in form of release probability increase that\r\ncould be explained by the increase of VGCCs at the presynaptic side. Our results strengthen\r\nthe idea of distributed cerebellar plasticity contributing to learning and provide a novel\r\nmechanism for release probability increase. " acknowledged_ssus: - _id: EM-Fac - _id: Bio - _id: PreCl alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Catarina full_name: Alcarva, Catarina id: 3A96634C-F248-11E8-B48F-1D18A9856A87 last_name: Alcarva citation: ama: 'Alcarva C. Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. 2023. doi:10.15479/at:ista:12809' apa: 'Alcarva, C. (2023). Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12809' chicago: 'Alcarva, Catarina. “Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12809.' ieee: 'C. Alcarva, “Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning,” Institute of Science and Technology Austria, 2023.' ista: 'Alcarva C. 2023. Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning. Institute of Science and Technology Austria.' mla: 'Alcarva, Catarina. Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12809.' short: 'C. Alcarva, Plasticity in the Cerebellum: What Molecular Mechanisms Are behind Physiological Learning, Institute of Science and Technology Austria, 2023.' corr_author: '1' date_created: 2023-04-06T07:54:09Z date_published: 2023-04-06T00:00:00Z date_updated: 2026-04-07T13:53:28Z day: '06' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: RySh doi: 10.15479/at:ista:12809 file: - access_level: open_access checksum: 35b5997d2b0acb461f9d33d073da0df5 content_type: application/pdf creator: cchlebak date_created: 2023-04-07T06:16:06Z date_updated: 2024-04-08T22:30:03Z embargo: 2024-04-07 file_id: '12814' file_name: Thesis_CatarinaAlcarva_final pdfA.pdf file_size: 9881969 relation: main_file - access_level: closed checksum: 81198f63c294890f6d58e8b29782efdc content_type: application/pdf creator: cchlebak date_created: 2023-04-07T06:17:11Z date_updated: 2024-04-08T22:30:03Z embargo_to: open_access file_id: '12815' file_name: Thesis_CatarinaAlcarva_final_for printing.pdf file_size: 44201583 relation: source_file - access_level: closed checksum: 0317bf7f457bb585f99d453ffa69eb53 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2023-04-07T06:18:05Z date_updated: 2024-04-08T22:30:03Z embargo_to: open_access file_id: '12816' file_name: Thesis_CatarinaAlcarva_final.docx file_size: 84731244 relation: source_file file_date_updated: 2024-04-08T22:30:03Z has_accepted_license: '1' language: - iso: eng month: '04' oa: 1 oa_version: Published Version page: '115' project: - _id: 267DFB90-B435-11E9-9278-68D0E5697425 name: 'Plasticity in the cerebellum: Which molecular mechanisms are behind physiological learning?' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Ryuichi full_name: Shigemoto, Ryuichi id: 499F3ABC-F248-11E8-B48F-1D18A9856A87 last_name: Shigemoto orcid: 0000-0001-8761-9444 title: 'Plasticity in the cerebellum: What molecular mechanisms are behind physiological learning' type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '12891' abstract: - lang: eng text: "The tight spatiotemporal coordination of signaling activity determining embryo\r\npatterning and the physical processes driving embryo morphogenesis renders\r\nembryonic development robust, such that key developmental processes can unfold\r\nrelatively normally even outside of the full embryonic context. For instance, embryonic\r\nstem cell cultures can recapitulate the hallmarks of gastrulation, i.e. break symmetry\r\nleading to germ layer formation and morphogenesis, in a very reduced environment.\r\nThis leads to questions on specific contributions of embryo-specific features, such as\r\nthe presence of extraembryonic tissues, which are inherently involved in gastrulation\r\nin the full embryonic context. To address this, we established zebrafish embryonic\r\nexplants without the extraembryonic yolk cell, an important player as a signaling\r\nsource and for morphogenesis during gastrulation, as a model of ex vivo development.\r\nWe found that dorsal-marginal determinants are required and sufficient in these\r\nexplants to form and pattern all three germ layers. However, formation of tissues,\r\nwhich require the highest Nodal-signaling levels, is variable, demonstrating a\r\ncontribution of extraembryonic tissues for reaching peak Nodal signaling levels.\r\nBlastoderm explants also undergo gastrulation-like axis elongation. We found that this\r\nelongation movement shows hallmarks of oriented mesendoderm cell intercalations\r\ntypically associated with dorsal tissues in the intact embryo. These are disrupted by\r\nuniform upregulation of BMP signaling activity and concomitant explant ventralization,\r\nsuggesting that tight spatial control of BMP signaling is a prerequisite for explant\r\nmorphogenesis. This control is achieved by Nodal signaling, which is critical for\r\neffectively downregulating BMP signaling in the mesendoderm, highlighting that Nodal\r\nsignaling is not only directly required for mesendoderm cell fate specification and\r\nmorphogenesis, but also by maintaining low levels of BMP signaling at the dorsal side.\r\nCollectively, we provide insights into the capacity and organization of signaling and\r\nmorphogenetic domains to recapitulate features of zebrafish gastrulation outside of\r\nthe full embryonic context." acknowledged_ssus: - _id: Bio - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Alexandra full_name: Schauer, Alexandra id: 30A536BA-F248-11E8-B48F-1D18A9856A87 last_name: Schauer orcid: 0000-0001-7659-9142 citation: ama: 'Schauer A. Mesendoderm formation in zebrafish gastrulation: The role of extraembryonic tissues. 2023. doi:10.15479/at:ista:12891' apa: 'Schauer, A. (2023). Mesendoderm formation in zebrafish gastrulation: The role of extraembryonic tissues. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12891' chicago: 'Schauer, Alexandra. “Mesendoderm Formation in Zebrafish Gastrulation: The Role of Extraembryonic Tissues.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12891.' ieee: 'A. Schauer, “Mesendoderm formation in zebrafish gastrulation: The role of extraembryonic tissues,” Institute of Science and Technology Austria, 2023.' ista: 'Schauer A. 2023. Mesendoderm formation in zebrafish gastrulation: The role of extraembryonic tissues. Institute of Science and Technology Austria.' mla: 'Schauer, Alexandra. Mesendoderm Formation in Zebrafish Gastrulation: The Role of Extraembryonic Tissues. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12891.' short: 'A. Schauer, Mesendoderm Formation in Zebrafish Gastrulation: The Role of Extraembryonic Tissues, Institute of Science and Technology Austria, 2023.' corr_author: '1' date_created: 2023-05-05T08:48:20Z date_published: 2023-05-05T00:00:00Z date_updated: 2025-06-12T06:56:58Z day: '05' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: CaHe doi: 10.15479/at:ista:12891 ec_funded: 1 file: - access_level: open_access checksum: 59b0303dc483f40a96a610a90aab7ee9 content_type: application/pdf creator: aschauer date_created: 2023-05-05T13:01:14Z date_updated: 2024-05-06T22:30:03Z embargo: 2024-05-05 file_id: '12907' file_name: Thesis_Schauer_final.pdf file_size: 31434230 relation: main_file - access_level: closed checksum: 25f54e12479b6adaabd129a20568e6c1 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: aschauer date_created: 2023-05-05T13:04:15Z date_updated: 2024-05-06T22:30:03Z embargo_to: open_access file_id: '12908' file_name: Thesis_Schauer_final.docx file_size: 43809109 relation: source_file file_date_updated: 2024-05-06T22:30:03Z has_accepted_license: '1' language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '190' project: - _id: 260F1432-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '742573' name: Interaction and feedback between cell mechanics and fate specification in vertebrate gastrulation - _id: 26B1E39C-B435-11E9-9278-68D0E5697425 grant_number: '25239' name: 'Mesendoderm specification in zebrafish: The role of extraembryonic tissues' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '7888' relation: part_of_dissertation status: public - id: '8966' relation: part_of_dissertation status: public status: public supervisor: - first_name: Carl-Philipp J full_name: Heisenberg, Carl-Philipp J id: 39427864-F248-11E8-B48F-1D18A9856A87 last_name: Heisenberg orcid: 0000-0002-0912-4566 title: 'Mesendoderm formation in zebrafish gastrulation: The role of extraembryonic tissues' type: dissertation user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '14656' abstract: - lang: eng text: Although much is known about how single neurons in the hippocampus represent an animal's position, how circuit interactions contribute to spatial coding is less well understood. Using a novel statistical estimator and theoretical modeling, both developed in the framework of maximum entropy models, we reveal highly structured CA1 cell-cell interactions in male rats during open field exploration. The statistics of these interactions depend on whether the animal is in a familiar or novel environment. In both conditions the circuit interactions optimize the encoding of spatial information, but for regimes that differ in the informativeness of their spatial inputs. This structure facilitates linear decodability, making the information easy to read out by downstream circuits. Overall, our findings suggest that the efficient coding hypothesis is not only applicable to individual neuron properties in the sensory periphery, but also to neural interactions in the central brain. acknowledgement: M.N. was supported by the European Union Horizon 2020 Grant 665385. J.C. was supported by the European Research Council Consolidator Grant 281511. G.T. was supported by the Austrian Science Fund (FWF) Grant P34015. C.S. was supported by an Institute of Science and Technology fellow award and by the National Science Foundation (NSF) Award No. 1922658. We thank Peter Baracskay, Karola Kaefer, and Hugo Malagon-Vina for the acquisition of the data. We also thank Federico Stella, Wiktor Młynarski, Dori Derdikman, Colin Bredenberg, Roman Huszar, Heloisa Chiossi, Lorenzo Posani, and Mohamady El-Gaby for comments on an earlier version of the manuscript. article_processing_charge: Yes (in subscription journal) article_type: original author: - first_name: Michele full_name: Nardin, Michele id: 30BD0376-F248-11E8-B48F-1D18A9856A87 last_name: Nardin orcid: 0000-0001-8849-6570 - first_name: Jozsef L full_name: Csicsvari, Jozsef L id: 3FA14672-F248-11E8-B48F-1D18A9856A87 last_name: Csicsvari orcid: 0000-0002-5193-4036 - first_name: Gašper full_name: Tkačik, Gašper id: 3D494DCA-F248-11E8-B48F-1D18A9856A87 last_name: Tkačik orcid: 0000-0002-6699-1455 - first_name: Cristina full_name: Savin, Cristina id: 3933349E-F248-11E8-B48F-1D18A9856A87 last_name: Savin citation: ama: Nardin M, Csicsvari JL, Tkačik G, Savin C. The structure of hippocampal CA1 interactions optimizes spatial coding across experience. The Journal of Neuroscience. 2023;43(48):8140-8156. doi:10.1523/JNEUROSCI.0194-23.2023 apa: Nardin, M., Csicsvari, J. L., Tkačik, G., & Savin, C. (2023). The structure of hippocampal CA1 interactions optimizes spatial coding across experience. The Journal of Neuroscience. Society for Neuroscience. https://doi.org/10.1523/JNEUROSCI.0194-23.2023 chicago: Nardin, Michele, Jozsef L Csicsvari, Gašper Tkačik, and Cristina Savin. “The Structure of Hippocampal CA1 Interactions Optimizes Spatial Coding across Experience.” The Journal of Neuroscience. Society for Neuroscience, 2023. https://doi.org/10.1523/JNEUROSCI.0194-23.2023. ieee: M. Nardin, J. L. Csicsvari, G. Tkačik, and C. Savin, “The structure of hippocampal CA1 interactions optimizes spatial coding across experience,” The Journal of Neuroscience, vol. 43, no. 48. Society for Neuroscience, pp. 8140–8156, 2023. ista: Nardin M, Csicsvari JL, Tkačik G, Savin C. 2023. The structure of hippocampal CA1 interactions optimizes spatial coding across experience. The Journal of Neuroscience. 43(48), 8140–8156. mla: Nardin, Michele, et al. “The Structure of Hippocampal CA1 Interactions Optimizes Spatial Coding across Experience.” The Journal of Neuroscience, vol. 43, no. 48, Society for Neuroscience, 2023, pp. 8140–56, doi:10.1523/JNEUROSCI.0194-23.2023. short: M. Nardin, J.L. Csicsvari, G. Tkačik, C. Savin, The Journal of Neuroscience 43 (2023) 8140–8156. date_created: 2023-12-10T23:00:58Z date_published: 2023-11-29T00:00:00Z date_updated: 2025-09-09T13:37:51Z day: '29' ddc: - '570' department: - _id: JoCs - _id: GaTk doi: 10.1523/JNEUROSCI.0194-23.2023 ec_funded: 1 external_id: isi: - '001148071000005' pmid: - '37758476' file: - access_level: open_access checksum: e2503c8f84be1050e28f64320f1d5bd2 content_type: application/pdf creator: dernst date_created: 2023-12-11T11:30:37Z date_updated: 2024-06-02T22:30:03Z embargo: 2024-06-01 file_id: '14674' file_name: 2023_JourNeuroscience_Nardin.pdf file_size: 2280632 relation: main_file file_date_updated: 2024-06-02T22:30:03Z has_accepted_license: '1' intvolume: ' 43' isi: 1 issue: '48' language: - iso: eng month: '11' oa: 1 oa_version: Published Version page: 8140-8156 pmid: 1 project: - _id: 257A4776-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '281511' name: Memory-related information processing in neuronal circuits of the hippocampus and entorhinal cortex - _id: 626c45b5-2b32-11ec-9570-e509828c1ba6 grant_number: P34015 name: Efficient coding with biophysical realism - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication: The Journal of Neuroscience publication_identifier: eissn: - 1529-2401 publication_status: published publisher: Society for Neuroscience quality_controlled: '1' related_material: record: - id: '10077' relation: earlier_version status: public scopus_import: '1' status: public title: The structure of hippocampal CA1 interactions optimizes spatial coding across experience tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 43 year: '2023' ... --- _id: '13201' abstract: - lang: eng text: As a crucial nitrogen source, nitrate (NO3−) is a key nutrient for plants. Accordingly, root systems adapt to maximize NO3− availability, a developmental regulation also involving the phytohormone auxin. Nonetheless, the molecular mechanisms underlying this regulation remain poorly understood. Here, we identify low-nitrate-resistant mutant (lonr) in Arabidopsis (Arabidopsis thaliana), whose root growth fails to adapt to low-NO3− conditions. lonr2 is defective in the high-affinity NO3− transporter NRT2.1. lonr2 (nrt2.1) mutants exhibit defects in polar auxin transport, and their low-NO3−-induced root phenotype depends on the PIN7 auxin exporter activity. NRT2.1 directly associates with PIN7 and antagonizes PIN7-mediated auxin efflux depending on NO3− levels. These results reveal a mechanism by which NRT2.1 in response to NO3− limitation directly regulates auxin transport activity and, thus, root growth. This adaptive mechanism contributes to the root developmental plasticity to help plants cope with changes in NO3− availability. acknowledgement: We are grateful to Caifu Jiang for providing ethyl metha-nesulfonate- mutagenized population, Yi Wang for providing Xenopus oocytes, Jun Fan and Zhaosheng Kong for providing tobacco BY- 2 cells, and Claus Schwechheimer, Alain Gojon, and Shutang Tan for helpful discussions. This work was supported by the National Key Research and Development Program of China (2021YFF1000500), the National Natural Science Foundation of China (32170265 and 32022007), Hainan Provincial Natural Science Foundation of China (323CXTD379), Chinese Universities Scientific Fund (2023TC019), Beijing Municipal Natural Science Foundation (5192011), Beijing Outstanding University Discipline Program, and China Postdoctoral Science Foundation (BH2020259460). article_number: e2221313120 article_processing_charge: No article_type: original author: - first_name: Yalu full_name: Wang, Yalu last_name: Wang - first_name: Zhi full_name: Yuan, Zhi last_name: Yuan - first_name: Jinyi full_name: Wang, Jinyi last_name: Wang - first_name: Huixin full_name: Xiao, Huixin last_name: Xiao - first_name: Lu full_name: Wan, Lu last_name: Wan - first_name: Lanxin full_name: Li, Lanxin id: 367EF8FA-F248-11E8-B48F-1D18A9856A87 last_name: Li orcid: 0000-0002-5607-272X - first_name: Yan full_name: Guo, Yan last_name: Guo - first_name: Zhizhong full_name: Gong, Zhizhong last_name: Gong - first_name: Jiří full_name: Friml, Jiří id: 4159519E-F248-11E8-B48F-1D18A9856A87 last_name: Friml orcid: 0000-0002-8302-7596 - first_name: Jing full_name: Zhang, Jing last_name: Zhang citation: ama: Wang Y, Yuan Z, Wang J, et al. The nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation. Proceedings of the National Academy of Sciences of the United States of America. 2023;120(25). doi:10.1073/pnas.2221313120 apa: Wang, Y., Yuan, Z., Wang, J., Xiao, H., Wan, L., Li, L., … Zhang, J. (2023). The nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation. Proceedings of the National Academy of Sciences of the United States of America. National Academy of Sciences. https://doi.org/10.1073/pnas.2221313120 chicago: Wang, Yalu, Zhi Yuan, Jinyi Wang, Huixin Xiao, Lu Wan, Lanxin Li, Yan Guo, Zhizhong Gong, Jiří Friml, and Jing Zhang. “The Nitrate Transporter NRT2.1 Directly Antagonizes PIN7-Mediated Auxin Transport for Root Growth Adaptation.” Proceedings of the National Academy of Sciences of the United States of America. National Academy of Sciences, 2023. https://doi.org/10.1073/pnas.2221313120. ieee: Y. Wang et al., “The nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation,” Proceedings of the National Academy of Sciences of the United States of America, vol. 120, no. 25. National Academy of Sciences, 2023. ista: Wang Y, Yuan Z, Wang J, Xiao H, Wan L, Li L, Guo Y, Gong Z, Friml J, Zhang J. 2023. The nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation. Proceedings of the National Academy of Sciences of the United States of America. 120(25), e2221313120. mla: Wang, Yalu, et al. “The Nitrate Transporter NRT2.1 Directly Antagonizes PIN7-Mediated Auxin Transport for Root Growth Adaptation.” Proceedings of the National Academy of Sciences of the United States of America, vol. 120, no. 25, e2221313120, National Academy of Sciences, 2023, doi:10.1073/pnas.2221313120. short: Y. Wang, Z. Yuan, J. Wang, H. Xiao, L. Wan, L. Li, Y. Guo, Z. Gong, J. Friml, J. Zhang, Proceedings of the National Academy of Sciences of the United States of America 120 (2023). date_created: 2023-07-09T22:01:12Z date_published: 2023-06-12T00:00:00Z date_updated: 2023-12-13T23:30:04Z day: '12' ddc: - '570' department: - _id: JiFr doi: 10.1073/pnas.2221313120 external_id: isi: - '001030689600003' pmid: - '37307446' file: - access_level: open_access checksum: d800e06252eaefba28531fa9440f23f0 content_type: application/pdf creator: alisjak date_created: 2023-07-10T08:48:40Z date_updated: 2023-12-13T23:30:03Z embargo: 2023-12-12 file_id: '13204' file_name: 2023_PNAS_Wang.pdf file_size: 5244581 relation: main_file file_date_updated: 2023-12-13T23:30:03Z has_accepted_license: '1' intvolume: ' 120' isi: 1 issue: '25' language: - iso: eng license: https://creativecommons.org/licenses/by-nc-nd/4.0/ month: '06' oa: 1 oa_version: Published Version pmid: 1 publication: Proceedings of the National Academy of Sciences of the United States of America publication_identifier: eissn: - 1091-6490 issn: - 0027-8424 publication_status: published publisher: National Academy of Sciences quality_controlled: '1' scopus_import: '1' status: public title: The nitrate transporter NRT2.1 directly antagonizes PIN7-mediated auxin transport for root growth adaptation tmp: image: /images/cc_by_nc_nd.png legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) short: CC BY-NC-ND (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 120 year: '2023' ... --- OA_place: publisher _id: '14622' abstract: - lang: eng text: "This Ph.D. thesis presents a detailed investigation into Variational Quantum Algorithms\r\n(VQAs), a promising class of quantum algorithms that are well suited for near-term quantum\r\ncomputation due to their moderate hardware requirements and resilience to noise. Our\r\nprimary focus lies on two particular types of VQAs: the Quantum Approximate Optimization\r\nAlgorithm (QAOA), used for solving binary optimization problems, and the Variational Quantum\r\nEigensolver (VQE), utilized for finding ground states of quantum many-body systems.\r\nIn the first part of the thesis, we examine the issue of effective parameter initialization for\r\nthe QAOA. The work demonstrates that random initialization of the QAOA often leads to\r\nconvergence in local minima with sub-optimal performance. To mitigate this issue, we propose\r\nan initialization of QAOA parameters based on the Trotterized Quantum Annealing (TQA).\r\nWe show that TQA initialization leads to the same performance as the best of an exponentially\r\nscaling number of random initializations.\r\nThe second study introduces Transition States (TS), stationary points with a single direction\r\nof descent, as a tool for systematically exploring the QAOA optimization landscape. This\r\nleads us to propose a novel greedy parameter initialization strategy that guarantees for the\r\nenergy to decrease with increasing number of circuit layers.\r\nIn the third section, we extend the QAOA to qudit systems, which are higher-dimensional\r\ngeneralizations of qubits. This chapter provides theoretical insights and practical strategies for\r\nleveraging the increased computational power of qudits in the context of quantum optimization\r\nalgorithms and suggests a quantum circuit for implementing the algorithm on an ion trap\r\nquantum computer.\r\nFinally, we propose an algorithm to avoid “barren plateaus”, regions in parameter space with\r\nvanishing gradients that obstruct efficient parameter optimization. This novel approach relies\r\non defining a notion of weak barren plateaus based on the entropies of local reduced density\r\nmatrices and showcases how these can be efficiently quantified using shadow tomography.\r\nTo illustrate the approach we employ the strategy in the VQE and show that it allows to\r\nsuccessfully avoid barren plateaus in the initialization and throughout the optimization.\r\nTaken together, this thesis greatly enhances our understanding of parameter initialization and\r\noptimization in VQAs, expands the scope of QAOA to higher-dimensional quantum systems,\r\nand presents a method to address the challenge of barren plateaus using the VQE. These\r\ninsights are instrumental in advancing the field of near-term quantum computation." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack orcid: 0000-0001-5400-8508 citation: ama: 'Sack S. Improving variational quantum algorithms : Innovative initialization techniques and extensions to qudit systems. 2023. doi:10.15479/at:ista:14622' apa: 'Sack, S. (2023). Improving variational quantum algorithms : Innovative initialization techniques and extensions to qudit systems. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14622' chicago: 'Sack, Stefan. “Improving Variational Quantum Algorithms : Innovative Initialization Techniques and Extensions to Qudit Systems.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14622.' ieee: 'S. Sack, “Improving variational quantum algorithms : Innovative initialization techniques and extensions to qudit systems,” Institute of Science and Technology Austria, 2023.' ista: 'Sack S. 2023. Improving variational quantum algorithms : Innovative initialization techniques and extensions to qudit systems. Institute of Science and Technology Austria.' mla: 'Sack, Stefan. Improving Variational Quantum Algorithms : Innovative Initialization Techniques and Extensions to Qudit Systems. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14622.' short: 'S. Sack, Improving Variational Quantum Algorithms : Innovative Initialization Techniques and Extensions to Qudit Systems, Institute of Science and Technology Austria, 2023.' corr_author: '1' date_created: 2023-11-28T10:58:13Z date_published: 2023-11-30T00:00:00Z date_updated: 2026-04-07T13:53:47Z day: '30' ddc: - '530' degree_awarded: PhD department: - _id: GradSch - _id: MaSe doi: 10.15479/at:ista:14622 ec_funded: 1 file: - access_level: open_access checksum: 068fd3570506ec42b2faa390de784bc4 content_type: application/pdf creator: ssack date_created: 2023-11-30T15:53:10Z date_updated: 2024-11-30T23:30:03Z embargo: 2024-11-30 file_id: '14635' file_name: PhD_Thesis.pdf file_size: 11947523 relation: main_file - access_level: closed checksum: 0fa3bc0d108aed0ac59d2c6beef2220a content_type: application/zip creator: ssack date_created: 2023-11-30T15:54:11Z date_updated: 2024-11-30T23:30:03Z embargo_to: open_access file_id: '14636' file_name: PhD Thesis (1).zip file_size: 18422964 relation: source_file file_date_updated: 2024-11-30T23:30:03Z has_accepted_license: '1' language: - iso: eng month: '11' oa: 1 oa_version: Published Version page: '142' project: - _id: bd660c93-d553-11ed-ba76-fb0fb6f49c0d name: IMB PhD Nomination Fellowship - Stefan Sack - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '13125' relation: part_of_dissertation status: public - id: '11471' relation: part_of_dissertation status: public - id: '9760' relation: part_of_dissertation status: public status: public supervisor: - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 title: 'Improving variational quantum algorithms : Innovative initialization techniques and extensions to qudit systems' tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '13125' abstract: - lang: eng text: 'The quantum approximate optimization algorithm (QAOA) is a variational quantum algorithm, where a quantum computer implements a variational ansatz consisting of p layers of alternating unitary operators and a classical computer is used to optimize the variational parameters. For a random initialization, the optimization typically leads to local minima with poor performance, motivating the search for initialization strategies of QAOA variational parameters. Although numerous heuristic initializations exist, an analytical understanding and performance guarantees for large p remain evasive.We introduce a greedy initialization of QAOA which guarantees improving performance with an increasing number of layers. Our main result is an analytic construction of 2p + 1 transition states—saddle points with a unique negative curvature direction—for QAOA with p + 1 layers that use the local minimum of QAOA with p layers. Transition states connect to new local minima, which are guaranteed to lower the energy compared to the minimum found for p layers. We use the GREEDY procedure to navigate the exponentially increasing with p number of local minima resulting from the recursive application of our analytic construction. The performance of the GREEDY procedure matches available initialization strategies while providing a guarantee for the minimal energy to decrease with an increasing number of layers p. ' acknowledgement: 'We thank V. Verteletskyi for a joint collaboration on numerical studies of the QAOA during his internship at ISTA that inspired analytic results on TS reported in this work. We acknowledge A. A. Mele and M. Brooks for discussions and D. Egger, P. Love, and D. Wierichs for valuable feedback on the manuscript. S.H.S., R.A.M., and M.S. acknowledge support by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899). R.K. is supported by the SFB BeyondC (Grant No. F7107-N38) and the project QuantumReady (FFG 896217). ' article_number: '062404' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Stefan full_name: Sack, Stefan id: dd622248-f6e0-11ea-865d-ce382a1c81a5 last_name: Sack orcid: 0000-0001-5400-8508 - first_name: Raimel A full_name: Medina Ramos, Raimel A id: CE680B90-D85A-11E9-B684-C920E6697425 last_name: Medina Ramos orcid: 0000-0002-5383-2869 - first_name: Richard full_name: Kueng, Richard last_name: Kueng - first_name: Maksym full_name: Serbyn, Maksym id: 47809E7E-F248-11E8-B48F-1D18A9856A87 last_name: Serbyn orcid: 0000-0002-2399-5827 citation: ama: Sack S, Medina Ramos RA, Kueng R, Serbyn M. Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. 2023;107(6). doi:10.1103/physreva.107.062404 apa: Sack, S., Medina Ramos, R. A., Kueng, R., & Serbyn, M. (2023). Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. American Physical Society. https://doi.org/10.1103/physreva.107.062404 chicago: Sack, Stefan, Raimel A Medina Ramos, Richard Kueng, and Maksym Serbyn. “Recursive Greedy Initialization of the Quantum Approximate Optimization Algorithm with Guaranteed Improvement.” Physical Review A. American Physical Society, 2023. https://doi.org/10.1103/physreva.107.062404. ieee: S. Sack, R. A. Medina Ramos, R. Kueng, and M. Serbyn, “Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement,” Physical Review A, vol. 107, no. 6. American Physical Society, 2023. ista: Sack S, Medina Ramos RA, Kueng R, Serbyn M. 2023. Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement. Physical Review A. 107(6), 062404. mla: Sack, Stefan, et al. “Recursive Greedy Initialization of the Quantum Approximate Optimization Algorithm with Guaranteed Improvement.” Physical Review A, vol. 107, no. 6, 062404, American Physical Society, 2023, doi:10.1103/physreva.107.062404. short: S. Sack, R.A. Medina Ramos, R. Kueng, M. Serbyn, Physical Review A 107 (2023). corr_author: '1' date_created: 2023-06-07T06:57:32Z date_published: 2023-06-02T00:00:00Z date_updated: 2026-06-18T22:30:20Z day: '02' ddc: - '530' department: - _id: MaSe doi: 10.1103/physreva.107.062404 ec_funded: 1 external_id: arxiv: - '2209.01159' isi: - '001016927100012' file: - access_level: open_access checksum: 0d71423888eeccaa60d8f41197f26306 content_type: application/pdf creator: dernst date_created: 2023-06-13T07:28:36Z date_updated: 2023-06-13T07:28:36Z file_id: '13131' file_name: 2023_PhysRevA_Sack.pdf file_size: 2524611 relation: main_file success: 1 file_date_updated: 2023-06-13T07:28:36Z has_accepted_license: '1' intvolume: ' 107' isi: 1 issue: '6' language: - iso: eng month: '06' oa: 1 oa_version: Published Version project: - _id: 23841C26-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '850899' name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control' publication: Physical Review A publication_identifier: eissn: - 2469-9934 issn: - 2469-9926 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: record: - id: '17208' relation: dissertation_contains status: public - id: '14622' relation: dissertation_contains status: public scopus_import: '1' status: public title: Recursive greedy initialization of the quantum approximate optimization algorithm with guaranteed improvement tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 107 year: '2023' ... --- _id: '12521' abstract: - lang: eng text: Differentiated X chromosomes are expected to have higher rates of adaptive divergence than autosomes, if new beneficial mutations are recessive (the “faster-X effect”), largely because these mutations are immediately exposed to selection in males. The evolution of X chromosomes after they stop recombining in males, but before they become hemizygous, has not been well explored theoretically. We use the diffusion approximation to infer substitution rates of beneficial and deleterious mutations under such a scenario. Our results show that selection is less efficient on diploid X loci than on autosomal and hemizygous X loci under a wide range of parameters. This “slower-X” effect is stronger for genes affecting primarily (or only) male fitness, and for sexually antagonistic genes. These unusual dynamics suggest that some of the peculiar features of X chromosomes, such as the differential accumulation of genes with sex-specific functions, may start arising earlier than previously appreciated. acknowledgement: We thank the Vicoso and Barton groups and ISTA Scientific Computing Unit. We also thank two anonymous reviewers for their valuable comments. This work was supported by the European Research Council under the European Union’s Horizon 2020 research and innovation program (grant agreements no. 715257 and no. 716117). article_number: qrac004 article_processing_charge: Yes (via OA deal) article_type: original author: - first_name: Andrea full_name: Mrnjavac, Andrea id: 353FAC84-AE61-11E9-8BFC-00D3E5697425 last_name: Mrnjavac - first_name: Kseniia full_name: Khudiakova, Kseniia id: 4E6DC800-AE37-11E9-AC72-31CAE5697425 last_name: Khudiakova orcid: 0000-0002-6246-1465 - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 - first_name: Beatriz full_name: Vicoso, Beatriz id: 49E1C5C6-F248-11E8-B48F-1D18A9856A87 last_name: Vicoso orcid: 0000-0002-4579-8306 citation: ama: 'Mrnjavac A, Khudiakova K, Barton NH, Vicoso B. Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. Evolution Letters. 2023;7(1). doi:10.1093/evlett/qrac004' apa: 'Mrnjavac, A., Khudiakova, K., Barton, N. H., & Vicoso, B. (2023). Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. Evolution Letters. Oxford University Press. https://doi.org/10.1093/evlett/qrac004' chicago: 'Mrnjavac, Andrea, Kseniia Khudiakova, Nicholas H Barton, and Beatriz Vicoso. “Slower-X: Reduced Efficiency of Selection in the Early Stages of X Chromosome Evolution.” Evolution Letters. Oxford University Press, 2023. https://doi.org/10.1093/evlett/qrac004.' ieee: 'A. Mrnjavac, K. Khudiakova, N. H. Barton, and B. Vicoso, “Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution,” Evolution Letters, vol. 7, no. 1. Oxford University Press, 2023.' ista: 'Mrnjavac A, Khudiakova K, Barton NH, Vicoso B. 2023. Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. Evolution Letters. 7(1), qrac004.' mla: 'Mrnjavac, Andrea, et al. “Slower-X: Reduced Efficiency of Selection in the Early Stages of X Chromosome Evolution.” Evolution Letters, vol. 7, no. 1, qrac004, Oxford University Press, 2023, doi:10.1093/evlett/qrac004.' short: A. Mrnjavac, K. Khudiakova, N.H. Barton, B. Vicoso, Evolution Letters 7 (2023). corr_author: '1' date_created: 2023-02-06T13:59:12Z date_published: 2023-02-01T00:00:00Z date_updated: 2026-06-18T22:30:24Z day: '01' ddc: - '570' department: - _id: GradSch - _id: BeVi doi: 10.1093/evlett/qrac004 ec_funded: 1 external_id: isi: - '001021692200001' pmid: - '37065438' file: - access_level: open_access checksum: a240a041cb9b9b7c8ba93a4706674a3f content_type: application/pdf creator: dernst date_created: 2023-08-16T11:43:33Z date_updated: 2023-08-16T11:43:33Z file_id: '14068' file_name: 2023_EvLetters_Mrnjavac.pdf file_size: 2592189 relation: main_file success: 1 file_date_updated: 2023-08-16T11:43:33Z has_accepted_license: '1' intvolume: ' 7' isi: 1 issue: '1' keyword: - Genetics - Ecology - Evolution - Behavior and Systematics language: - iso: eng month: '02' oa: 1 oa_version: Published Version pmid: 1 project: - _id: 256E75B8-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '716117' name: Optimal Transport and Stochastic Dynamics - _id: 250BDE62-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '715257' name: Prevalence and Influence of Sexual Antagonism on Genome Evolution publication: Evolution Letters publication_identifier: issn: - 2056-3744 publication_status: published publisher: Oxford University Press quality_controlled: '1' related_material: record: - id: '18531' relation: dissertation_contains status: public scopus_import: '1' status: public title: 'Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 7 year: '2023' ... --- OA_place: publisher _id: '14280' abstract: - lang: eng text: "Cell division in Escherichia coli is performed by the divisome, a multi-protein complex composed of more than 30 proteins. The divisome spans from the cytoplasm through the inner membrane to the cell wall and the outer membrane. Divisome assembly is initiated by a cytoskeletal structure, the so-called Z-ring, which localizes at the center of the E. coli cell and determines the position of the future cell septum. The Z-ring is composed of the highly conserved bacterial tubulin homologue FtsZ, which forms treadmilling filaments. These filaments are recruited to the inner membrane by FtsA, a highly conserved bacterial actin homologue. FtsA interacts with other proteins in the periplasm and thus connects the cytoplasmic and periplasmic components of the divisome. \r\nA previous model postulated that FtsA regulates maturation of the divisome by switching from an oligomeric, inactive state to a monomeric and active state. This model was based mostly on in vivo studies, as a biochemical characterization of FtsA has been hampered by difficulties in purifying the protein. Here, we studied FtsA using an in vitro reconstitution approach and aimed to answer two questions: (i) How are dynamics from cytoplasmic, treadmilling FtsZ filaments coupled to proteins acting in the periplasmic space and (ii) How does FtsA regulate the maturation of the divisome?\r\nWe found that the cytoplasmic peptides of the transmembrane proteins FtsN and FtsQ interact directly with FtsA and can follow the spatiotemporal signal of FtsA/Z filaments. When we investigated the underlying mechanism by imaging single molecules of FtsNcyto, we found the peptide to interact transiently with FtsA. An in depth analysis of the single molecule trajectories helped to postulate a model where PG synthases follow the dynamics of FtsZ by a diffusion and capture mechanism. \r\nFollowing up on these findings we were interested in how the self-interaction of FtsA changes when it encounters FtsNcyto and if we can confirm the proposed oligomer-monomer switch. For this, we compared the behavior of the previously identified, hyperactive mutant FtsA R286W with wildtype FtsA. The mutant outperforms WT in mirroring and transmitting the spatiotemporal signal of treadmilling FtsZ filaments. Surprisingly however, we found that this was not due to a difference in the self-interaction strength of the two variants, but a difference in their membrane residence time. Furthermore, in contrast to our expectations, upon binding of FtsNcyto the measured self-interaction of FtsA actually increased. \r\nWe propose that FtsNcyto induces a rearrangement of the oligomeric architecture of FtsA. In further consequence this change leads to more persistent FtsZ filaments which results in a defined signalling zone, allowing formation of the mature divisome. The observed difference between FtsA WT and R286W is due to the vastly different membrane turnover of the proteins. R286W cycles 5-10x faster compared to WT which allows to sample FtsZ filaments at faster frequencies. These findings can explain the observed differences in toxicity for overexpression of FtsA WT and R286W and help to understand how FtsA regulates divisome maturation." acknowledged_ssus: - _id: Bio - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Philipp full_name: Radler, Philipp id: 40136C2A-F248-11E8-B48F-1D18A9856A87 last_name: Radler orcid: '0000-0001-9198-2182 ' citation: ama: Radler P. Spatiotemporal signaling during assembly of the bacterial divisome. 2023. doi:10.15479/at:ista:14280 apa: Radler, P. (2023). Spatiotemporal signaling during assembly of the bacterial divisome. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14280 chicago: Radler, Philipp. “Spatiotemporal Signaling during Assembly of the Bacterial Divisome.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14280. ieee: P. Radler, “Spatiotemporal signaling during assembly of the bacterial divisome,” Institute of Science and Technology Austria, 2023. ista: Radler P. 2023. Spatiotemporal signaling during assembly of the bacterial divisome. Institute of Science and Technology Austria. mla: Radler, Philipp. Spatiotemporal Signaling during Assembly of the Bacterial Divisome. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14280. short: P. Radler, Spatiotemporal Signaling during Assembly of the Bacterial Divisome, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-09-06T10:58:25Z date_published: 2023-09-25T00:00:00Z date_updated: 2026-04-07T14:06:05Z day: '25' ddc: - '572' degree_awarded: PhD department: - _id: GradSch - _id: MaLo doi: 10.15479/at:ista:14280 ec_funded: 1 file: - access_level: closed checksum: 87eef11fbc5c7df0826f12a3a629b444 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: pradler date_created: 2023-10-04T10:11:53Z date_updated: 2024-10-05T22:30:03Z embargo_to: open_access file_id: '14390' file_name: PhD Thesis_Philipp Radler_20231004.docx file_size: 114932847 relation: source_file - access_level: open_access checksum: 3253e099b7126469d941fd9419d68b4f content_type: application/pdf creator: pradler date_created: 2023-10-04T10:11:21Z date_updated: 2024-10-05T22:30:03Z embargo: 2024-10-04 file_id: '14391' file_name: PhD Thesis_Philipp Radler_20231004.pdf file_size: 37838778 relation: main_file file_date_updated: 2024-10-05T22:30:03Z has_accepted_license: '1' keyword: - Cell Division - Reconstitution - FtsZ - FtsA - Divisome - E.coli language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '156' project: - _id: 2595697A-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '679239' name: Self-Organization of the Bacterial Cell - _id: fc38323b-9c52-11eb-aca3-ff8afb4a011d grant_number: P34607 name: In vitro reconstitution of bacterial cell division - _id: 2596EAB6-B435-11E9-9278-68D0E5697425 grant_number: ALTF 2015-1163 name: Synthesis of bacterial cell wall - _id: 259B655A-B435-11E9-9278-68D0E5697425 grant_number: LT000824/2016 name: Reconstitution of bacterial cell wall synthesis publication_identifier: isbn: - 978-3-99078-033-6 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '10934' relation: research_data status: public - id: '11373' relation: part_of_dissertation status: public - id: '7387' relation: part_of_dissertation status: public status: public supervisor: - first_name: Martin full_name: Loose, Martin id: 462D4284-F248-11E8-B48F-1D18A9856A87 last_name: Loose orcid: 0000-0001-7309-9724 title: Spatiotemporal signaling during assembly of the bacterial divisome tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ...