--- _id: '14587' abstract: - lang: eng text: "This thesis concerns the application of variational methods to the study of evolution problems arising in fluid mechanics and in material sciences. The main focus is on weak-strong stability properties of some curvature driven interface evolution problems, such as the two-phase Navier–Stokes flow with surface tension and multiphase mean curvature flow, and on the phase-field approximation of the latter. Furthermore, we discuss a variational approach to the study of a class of doubly nonlinear wave equations.\r\nFirst, we consider the two-phase Navier–Stokes flow with surface tension within a bounded domain. The two fluids are immiscible and separated by a sharp interface, which intersects the boundary of the domain at a constant contact angle of ninety degree. We devise a suitable concept of varifolds solutions for the associated interface evolution problem and we establish a weak-strong uniqueness principle in case of a two dimensional ambient space. In order to focus on the boundary effects and on the singular geometry of the evolving domains, we work for simplicity in the regime of same viscosities for the two fluids.\r\nThe core of the thesis consists in the rigorous proof of the convergence of the vectorial Allen-Cahn equation towards multiphase mean curvature flow for a suitable class of multi- well potentials and for well-prepared initial data. We even establish a rate of convergence. Our relative energy approach relies on the concept of gradient-flow calibration for branching singularities in multiphase mean curvature flow and thus enables us to overcome the limitations of other approaches. To the best of the author’s knowledge, our result is the first quantitative and unconditional one available in the literature for the vectorial/multiphase setting.\r\nThis thesis also contains a first study of weak-strong stability for planar multiphase mean curvature flow beyond the singularity resulting from a topology change. Previous weak-strong results are indeed limited to time horizons before the first topology change of the strong solution. We consider circular topology changes and we prove weak-strong stability for BV solutions to planar multiphase mean curvature flow beyond the associated singular times by dynamically adapting the strong solutions to the weak one by means of a space-time shift.\r\nIn the context of interface evolution problems, our proofs for the main results of this thesis are based on the relative energy technique, relying on novel suitable notions of relative energy functionals, which in particular measure the interface error. Our statements follow from the resulting stability estimates for the relative energy associated to the problem.\r\nAt last, we introduce a variational approach to the study of nonlinear evolution problems. This approach hinges on the minimization of a parameter dependent family of convex functionals over entire trajectories, known as Weighted Inertia-Dissipation-Energy (WIDE) functionals. We consider a class of doubly nonlinear wave equations and establish the convergence, up to subsequences, of the associated WIDE minimizers to a solution of the target problem as the parameter goes to zero." acknowledgement: The research projects contained in this thesis have received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 948819). alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Alice full_name: Marveggio, Alice id: 25647992-AA84-11E9-9D75-8427E6697425 last_name: Marveggio citation: ama: Marveggio A. Weak-strong stability and phase-field approximation of interface evolution problems in fluid mechanics and in material sciences. 2023. doi:10.15479/at:ista:14587 apa: Marveggio, A. (2023). Weak-strong stability and phase-field approximation of interface evolution problems in fluid mechanics and in material sciences. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14587 chicago: Marveggio, Alice. “Weak-Strong Stability and Phase-Field Approximation of Interface Evolution Problems in Fluid Mechanics and in Material Sciences.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14587. ieee: A. Marveggio, “Weak-strong stability and phase-field approximation of interface evolution problems in fluid mechanics and in material sciences,” Institute of Science and Technology Austria, 2023. ista: Marveggio A. 2023. Weak-strong stability and phase-field approximation of interface evolution problems in fluid mechanics and in material sciences. Institute of Science and Technology Austria. mla: Marveggio, Alice. Weak-Strong Stability and Phase-Field Approximation of Interface Evolution Problems in Fluid Mechanics and in Material Sciences. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14587. short: A. Marveggio, Weak-Strong Stability and Phase-Field Approximation of Interface Evolution Problems in Fluid Mechanics and in Material Sciences, Institute of Science and Technology Austria, 2023. date_created: 2023-11-21T11:41:05Z date_published: 2023-11-21T00:00:00Z date_updated: 2024-03-22T13:21:28Z day: '21' ddc: - '515' degree_awarded: PhD department: - _id: GradSch - _id: JuFi doi: 10.15479/at:ista:14587 ec_funded: 1 file: - access_level: open_access checksum: 6c7db4cc86da6cdc79f7f358dc7755d4 content_type: application/pdf creator: amarvegg date_created: 2023-11-29T09:09:31Z date_updated: 2023-11-29T09:09:31Z file_id: '14626' file_name: thesis_Marveggio.pdf file_size: 2881100 relation: main_file success: 1 - access_level: closed checksum: 52f28bdf95ec82cff39f3685f9c48e7d content_type: application/zip creator: amarvegg date_created: 2023-11-29T09:10:19Z date_updated: 2024-03-20T12:28:32Z file_id: '14627' file_name: Thesis_Marveggio.zip file_size: 10189696 relation: source_file file_date_updated: 2024-03-20T12:28:32Z has_accepted_license: '1' language: - iso: eng license: https://creativecommons.org/licenses/by-nc-sa/4.0/ month: '11' oa: 1 oa_version: Published Version page: '228' project: - _id: 0aa76401-070f-11eb-9043-b5bb049fa26d call_identifier: H2020 grant_number: '948819' name: Bridging Scales in Random Materials publication_identifier: issn: - 2663 - 337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11842' relation: part_of_dissertation status: public - id: '14597' relation: part_of_dissertation status: public status: public supervisor: - first_name: Julian L full_name: Fischer, Julian L id: 2C12A0B0-F248-11E8-B48F-1D18A9856A87 last_name: Fischer orcid: 0000-0002-0479-558X title: Weak-strong stability and phase-field approximation of interface evolution problems in fluid mechanics and in material sciences 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: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _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. date_created: 2023-02-02T14:50:20Z date_published: 2023-02-02T00:00:00Z date_updated: 2024-03-25T23:30:05Z 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: NÖ-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: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '14226' abstract: - lang: eng text: "We introduce the notion of a Faustian interchange in a 1-parameter family of smooth\r\nfunctions to generalize the medial axis to critical points of index larger than 0.\r\nWe construct and implement a general purpose algorithm for approximating such\r\ngeneralized medial axes." alternative_title: - ISTA Master's Thesis article_processing_charge: No author: - first_name: Elizabeth R full_name: Stephenson, Elizabeth R id: 2D04F932-F248-11E8-B48F-1D18A9856A87 last_name: Stephenson orcid: 0000-0002-6862-208X citation: ama: Stephenson ER. Generalizing medial axes with homology switches. 2023. doi:10.15479/at:ista:14226 apa: Stephenson, E. R. (2023). Generalizing medial axes with homology switches. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14226 chicago: Stephenson, Elizabeth R. “Generalizing Medial Axes with Homology Switches.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14226. ieee: E. R. Stephenson, “Generalizing medial axes with homology switches,” Institute of Science and Technology Austria, 2023. ista: Stephenson ER. 2023. Generalizing medial axes with homology switches. Institute of Science and Technology Austria. mla: Stephenson, Elizabeth R. Generalizing Medial Axes with Homology Switches. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14226. short: E.R. Stephenson, Generalizing Medial Axes with Homology Switches, Institute of Science and Technology Austria, 2023. date_created: 2023-08-24T13:01:18Z date_published: 2023-08-24T00:00:00Z date_updated: 2024-02-26T23:30:04Z day: '24' ddc: - '500' degree_awarded: MS department: - _id: GradSch - _id: HeEd doi: 10.15479/at:ista:14226 file: - access_level: closed checksum: 453caf851d75c3478c10ed09bd242a91 content_type: application/x-zip-compressed creator: cchlebak date_created: 2023-08-24T13:02:49Z date_updated: 2024-02-26T23:30:03Z embargo_to: open_access file_id: '14227' file_name: documents-export-2023-08-24.zip file_size: 15501411 relation: source_file - access_level: open_access checksum: 7349d29963d6695e555e171748648d9a content_type: application/pdf creator: cchlebak date_created: 2023-08-24T13:03:42Z date_updated: 2024-02-26T23:30:03Z embargo: 2024-02-25 file_id: '14228' file_name: thesis_pdf_a.pdf file_size: 6854783 relation: main_file file_date_updated: 2024-02-26T23:30:03Z has_accepted_license: '1' language: - iso: eng month: '08' oa: 1 oa_version: Published Version page: '43' publication_identifier: issn: - 2791-4585 publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Herbert full_name: Edelsbrunner, Herbert id: 3FB178DA-F248-11E8-B48F-1D18A9856A87 last_name: Edelsbrunner orcid: 0000-0002-9823-6833 title: Generalizing medial axes with homology switches type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '12470' abstract: - lang: eng text: "The brain is an exceptionally sophisticated organ consisting of billions of cells and trillions of \r\nconnections that orchestrate our cognition and behavior. To decode its complex connectivity, it is \r\npivotal to disentangle its intricate architecture spanning from cm-sized circuits down to tens of \r\nnm-small synapses.\r\nTo achieve this goal, I developed CATS – Comprehensive Analysis of nervous Tissue across \r\nScales, a versatile toolbox for obtaining a holistic view of nervous tissue context with (super\x02resolution) fluorescence microscopy. CATS combines comprehensive labeling of the extracellular\r\nspace, that is compatible with chemical fixation, with information on molecular markers, super\x02resolved data acquisition and machine-learning based data analysis for segmentation and synapse \r\nidentification.\r\nI used CATS to analyze key features of nervous tissue connectivity, ranging from whole tissue \r\narchitecture, neuronal in- and output-fields, down to synapse morphology.\r\nFocusing on the hippocampal circuitry, I quantified synaptic transmission properties of mossy \r\nfiber boutons and analyzed the connectivity pattern of dentate gyrus granule cells with CA3 \r\npyramidal neurons. This shows that CATS is a viable tool to study hallmarks of neuronal \r\nconnectivity with light microscopy." acknowledged_ssus: - _id: Bio - _id: LifeSc - _id: PreCl - _id: EM-Fac - _id: M-Shop - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Julia M full_name: Michalska, Julia M id: 443DB6DE-F248-11E8-B48F-1D18A9856A87 last_name: Michalska orcid: 0000-0003-3862-1235 citation: ama: Michalska JM. A versatile toolbox for the comprehensive analysis of nervous tissue organization with light microscopy. 2023. doi:10.15479/at:ista:12470 apa: Michalska, J. M. (2023). A versatile toolbox for the comprehensive analysis of nervous tissue organization with light microscopy. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12470 chicago: Michalska, Julia M. “A Versatile Toolbox for the Comprehensive Analysis of Nervous Tissue Organization with Light Microscopy.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12470. ieee: J. M. Michalska, “A versatile toolbox for the comprehensive analysis of nervous tissue organization with light microscopy,” Institute of Science and Technology Austria, 2023. ista: Michalska JM. 2023. A versatile toolbox for the comprehensive analysis of nervous tissue organization with light microscopy. Institute of Science and Technology Austria. mla: Michalska, Julia M. A Versatile Toolbox for the Comprehensive Analysis of Nervous Tissue Organization with Light Microscopy. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12470. short: J.M. Michalska, A Versatile Toolbox for the Comprehensive Analysis of Nervous Tissue Organization with Light Microscopy, Institute of Science and Technology Austria, 2023. date_created: 2023-01-31T15:10:53Z date_published: 2023-01-09T00:00:00Z date_updated: 2023-08-31T12:26:58Z day: '09' ddc: - '610' degree_awarded: PhD department: - _id: GradSch - _id: JoDa doi: 10.15479/at:ista:12470 ec_funded: 1 file: - access_level: open_access checksum: 1a2306e5f59f52df598e7ecfadf921ac content_type: application/pdf creator: cchlebak date_created: 2023-01-31T15:11:42Z date_updated: 2023-07-27T22:30:54Z embargo: 2023-07-09 file_id: '12471' file_name: 20230109_PhD_thesis_JM_final.pdf file_size: 41771714 relation: main_file - access_level: closed checksum: 0bebbdee0773443959e1f6ab8caf281f content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2023-01-31T15:11:51Z date_updated: 2023-07-10T22:30:04Z embargo_to: open_access file_id: '12472' file_name: 20230109_PhD_thesis_JM_final.docx file_size: 66983464 relation: source_file file_date_updated: 2023-07-27T22:30:54Z has_accepted_license: '1' language: - iso: eng month: '01' oa: 1 oa_version: Published Version page: '201' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program - _id: 26AA4EF2-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: W1232-B24 name: Molecular Drug Targets publication_identifier: isbn: - ' 978-3-99078-026-8' issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11943' relation: part_of_dissertation status: public - id: '11950' relation: part_of_dissertation status: public status: public supervisor: - first_name: Johann G full_name: Danzl, Johann G id: 42EFD3B6-F248-11E8-B48F-1D18A9856A87 last_name: Danzl orcid: 0000-0001-8559-3973 title: A versatile toolbox for the comprehensive analysis of nervous tissue organization with light microscopy 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: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '12531' abstract: - lang: eng text: "All visual experiences of the vertebrates begin with light being converted into electrical signals\r\nby the eye retina. Retinal ganglion cells (RGCs) are the neurons of the innermost layer of the\r\nmammal retina, and they transmit visual information to the rest of the brain.\r\nIt has been shown that RGCs vary in their morphology and genetic profiles, moreover they can\r\nbe unambiguously grouped into subtypes that share the same morphological and/or molecular\r\nproperties. However, in terms of RGCs function, it remains unclear how many distinct types\r\nthere are and what response properties their typology relies on. Even given the recent studies\r\nthat successfully classified RGCs in a patch of the retina [1] and in scotopic conditions [2], the\r\nquestion remains whether the found subtypes persist across the entire retina.\r\nIn this work, using a novel imaging method, we show that, when sampled from a large portion\r\nof the retina, RGCs can not be clearly divided into functional subtypes. We found that in\r\nphotopic conditions, which implies more prominent natural scene statistic differences across\r\nthe visual field, response properties can be exhibited by cells differently depending on their\r\nlocation in the retina, which leads to formation of a gradient of features rather than distinct\r\nclasses.\r\nThis finding suggests that RGCs follow a global organization across the visual field of the\r\nanimal, adapting each RGC subtype to the requirements imposed by the natural scene statistics." alternative_title: - ISTA Master's Thesis article_processing_charge: No author: - first_name: Kseniia full_name: Kirillova, Kseniia id: 8e3f931e-dc85-11ea-9058-e7b957bf23f0 last_name: Kirillova citation: ama: Kirillova K. Panoramic functional gradients across the mouse retina. 2023. doi:10.15479/at:ista:12531 apa: Kirillova, K. (2023). Panoramic functional gradients across the mouse retina. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12531 chicago: Kirillova, Kseniia. “Panoramic Functional Gradients across the Mouse Retina.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12531. ieee: K. Kirillova, “Panoramic functional gradients across the mouse retina,” Institute of Science and Technology Austria, 2023. ista: Kirillova K. 2023. Panoramic functional gradients across the mouse retina. Institute of Science and Technology Austria. mla: Kirillova, Kseniia. Panoramic Functional Gradients across the Mouse Retina. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12531. short: K. Kirillova, Panoramic Functional Gradients across the Mouse Retina, Institute of Science and Technology Austria, 2023. date_created: 2023-02-09T07:45:05Z date_published: 2023-02-08T00:00:00Z date_updated: 2024-02-09T23:30:04Z day: '08' ddc: - '570' degree_awarded: MS department: - _id: GradSch - _id: MaJö doi: 10.15479/at:ista:12531 file: - access_level: open_access checksum: 57d8da3a6c749eb1556b7435fe266a5f content_type: application/pdf creator: cchlebak date_created: 2023-02-09T08:03:32Z date_updated: 2024-02-09T23:30:03Z embargo: 2024-02-08 file_id: '12532' file_name: Thesis_Kseniia___ISTA__istaustriathesis_PDF-A.pdf file_size: 8369317 relation: main_file - access_level: closed checksum: 87fb44318e4f9eb9da2ad9ad6ca8e76f content_type: application/x-zip-compressed creator: cchlebak date_created: 2023-02-10T09:32:06Z date_updated: 2024-02-09T23:30:03Z embargo_to: open_access file_id: '12535' file_name: Thesis Kseniia - ISTA [istaustriathesis]-FINAL.zip file_size: 11204408 relation: source_file file_date_updated: 2024-02-09T23:30:03Z has_accepted_license: '1' language: - iso: eng month: '02' oa: 1 oa_version: Published Version page: '46' publication_identifier: issn: - 2791-4585 publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Maximilian A full_name: Jösch, Maximilian A id: 2BD278E6-F248-11E8-B48F-1D18A9856A87 last_name: Jösch orcid: 0000-0002-3937-1330 title: Panoramic functional gradients across the mouse retina 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: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2023' ... --- _id: '12800' abstract: - lang: eng text: 'The evolutionary processes that brought about today’s plethora of living species and the many billions more ancient ones all underlie biology. Evolutionary pathways are neither directed nor deterministic, but rather an interplay between selection, migration, mutation, genetic drift and other environmental factors. Hybrid zones, as natural crossing experiments, offer a great opportunity to use cline analysis to deduce different evolutionary processes - for example, selection strength. Theoretical cline models, largely assuming uniform distribution of individuals, often lack the capability of incorporating population structure. Since in reality organisms mostly live in patchy distributions and their dispersal is hardly ever Gaussian, it is necessary to unravel the effect of these different elements of population structure on cline parameters and shape. In this thesis, I develop a simulation inspired by the A. majus hybrid zone of a single selected locus under frequency dependent selection. This simulation enables us to untangle the effects of different elements of population structure as for example a low-density center and long-range dispersal. This thesis is therefore a first step towards theoretically untangling the effects of different elements of population structure on cline parameters and shape. ' alternative_title: - ISTA Master's Thesis article_processing_charge: No author: - first_name: Mara full_name: Julseth, Mara id: 1cf464b2-dc7d-11ea-9b2f-f9b1aa9417d1 last_name: Julseth citation: ama: Julseth M. The effect of local population structure on genetic variation at selected loci in the A. majus hybrid zone. 2023. doi:10.15479/at:ista:12800 apa: Julseth, M. (2023). The effect of local population structure on genetic variation at selected loci in the A. majus hybrid zone. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12800 chicago: Julseth, Mara. “The Effect of Local Population Structure on Genetic Variation at Selected Loci in the A. Majus Hybrid Zone.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12800. ieee: M. Julseth, “The effect of local population structure on genetic variation at selected loci in the A. majus hybrid zone,” Institute of Science and Technology Austria, 2023. ista: Julseth M. 2023. The effect of local population structure on genetic variation at selected loci in the A. majus hybrid zone. Institute of Science and Technology Austria. mla: Julseth, Mara. The Effect of Local Population Structure on Genetic Variation at Selected Loci in the A. Majus Hybrid Zone. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12800. short: M. Julseth, The Effect of Local Population Structure on Genetic Variation at Selected Loci in the A. Majus Hybrid Zone, Institute of Science and Technology Austria, 2023. date_created: 2023-04-04T18:57:11Z date_published: 2023-04-05T00:00:00Z date_updated: 2023-06-02T22:30:05Z day: '05' ddc: - '576' degree_awarded: MS department: - _id: GradSch - _id: NiBa doi: 10.15479/at:ista:12800 file: - access_level: closed checksum: b76cf6d69f2093d8248f6a3f9d4654a4 content_type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet creator: mjulseth date_created: 2023-04-06T06:09:40Z date_updated: 2023-06-02T22:30:04Z embargo_to: open_access file_id: '12805' file_name: Dispersaldata.xlsx file_size: 52795 relation: supplementary_material - access_level: open_access checksum: 5a13b6d204371572e249f03795bc0d04 content_type: application/vnd.wolfram.nb creator: mjulseth date_created: 2023-04-06T06:11:27Z date_updated: 2023-06-02T22:30:04Z embargo: 2023-06-01 file_id: '12806' file_name: 2023_MSc_ThesisMaraJulseth_Notebook.nb file_size: 787239 relation: supplementary_material - access_level: closed checksum: c3ec842839ed1e66bf2618ae33047df8 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: mjulseth date_created: 2023-04-06T08:26:12Z date_updated: 2023-06-02T22:30:04Z embargo_to: open_access file_id: '12812' file_name: ThesisMaraJulseth_04_23.docx file_size: 1061763 relation: source_file - access_level: open_access checksum: 3132cc998fbe3ae2a3a83c2a69367f37 content_type: application/pdf creator: mjulseth date_created: 2023-04-06T08:26:37Z date_updated: 2023-06-02T22:30:04Z embargo: 2023-06-01 file_id: '12813' file_name: ThesisMaraJulseth_04_23.pdf file_size: 1741364 relation: main_file file_date_updated: 2023-06-02T22:30:04Z has_accepted_license: '1' language: - iso: eng month: '04' oa: 1 oa_version: Published Version page: '21' publication_identifier: issn: - 2791-4585 publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 title: The effect of local population structure on genetic variation at selected loci in the A. majus hybrid zone type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '14510' acknowledged_ssus: - _id: EM-Fac - _id: Bio - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Nataliia full_name: Gnyliukh, Nataliia id: 390C1120-F248-11E8-B48F-1D18A9856A87 last_name: Gnyliukh orcid: 0000-0002-2198-0509 citation: ama: Gnyliukh N. Mechanism of clathrin-coated vesicle  formation during endocytosis in plants. 2023. doi:10.15479/at:ista:14510 apa: Gnyliukh, N. (2023). Mechanism of clathrin-coated vesicle  formation during endocytosis in plants. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14510 chicago: Gnyliukh, Nataliia. “Mechanism of Clathrin-Coated Vesicle  Formation during Endocytosis in Plants.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14510. ieee: N. Gnyliukh, “Mechanism of clathrin-coated vesicle  formation during endocytosis in plants,” Institute of Science and Technology Austria, 2023. ista: Gnyliukh N. 2023. Mechanism of clathrin-coated vesicle  formation during endocytosis in plants. Institute of Science and Technology Austria. mla: Gnyliukh, Nataliia. Mechanism of Clathrin-Coated Vesicle  Formation during Endocytosis in Plants. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14510. short: N. Gnyliukh, Mechanism of Clathrin-Coated Vesicle  Formation during Endocytosis in Plants, Institute of Science and Technology Austria, 2023. date_created: 2023-11-10T09:10:06Z date_published: 2023-11-10T00:00:00Z date_updated: 2024-03-27T23:30:45Z day: '10' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: JiFr - _id: MaLo doi: 10.15479/at:ista:14510 ec_funded: 1 file: - access_level: closed checksum: 3d5e680bfc61f98e308c434f45cc9bd6 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: ngnyliuk date_created: 2023-11-20T09:18:51Z date_updated: 2023-11-20T09:18:51Z file_id: '14567' file_name: Thesis_Gnyliukh_final_08_11_23.docx file_size: 20824903 relation: source_file - access_level: closed checksum: bfc96d47fc4e7e857dd71656097214a4 content_type: application/pdf creator: ngnyliuk date_created: 2023-11-20T09:23:11Z date_updated: 2023-11-23T13:10:55Z embargo: 2024-11-23 embargo_to: open_access file_id: '14568' file_name: Thesis_Gnyliukh_final_20_11_23.pdf file_size: 24871844 relation: main_file file_date_updated: 2023-11-23T13:10:55Z has_accepted_license: '1' keyword: - Clathrin-Mediated Endocytosis - vesicle scission - Dynamin-Related Protein 2 - SH3P2 - TPLATE complex - Total internal reflection fluorescence microscopy - Arabidopsis thaliana language: - iso: eng month: '11' oa_version: Published Version page: '180' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-037-4 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '14591' relation: part_of_dissertation status: public - id: '9887' relation: part_of_dissertation status: public - id: '8139' relation: part_of_dissertation status: public status: public supervisor: - first_name: Jiří full_name: Friml, Jiří id: 4159519E-F248-11E8-B48F-1D18A9856A87 last_name: Friml orcid: 0000-0002-8302-7596 - first_name: Martin full_name: Loose, Martin id: 462D4284-F248-11E8-B48F-1D18A9856A87 last_name: Loose orcid: 0000-0001-7309-9724 title: Mechanism of clathrin-coated vesicle formation during endocytosis in plants 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: 8b945eb4-e2f2-11eb-945a-df72226e66a9 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.' date_created: 2023-05-05T10:40:14Z date_published: 2023-05-05T00:00:00Z date_updated: 2024-01-29T10:47:51Z 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: '7117' relation: part_of_dissertation status: public - id: '13188' relation: dissertation_contains 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: '12072' abstract: - lang: eng text: "In this thesis, we study two of the most important questions in Arithmetic geometry: that of the existence and density of solutions to Diophantine equations. In order for a Diophantine equation to have any solutions over the rational numbers, it must have solutions everywhere locally, i.e., over R and over Qp for every prime p. The converse, called the Hasse principle, is known to fail in general. However, it is still a central question in Arithmetic geometry to determine for which varieties the Hasse principle does hold. In this work, we establish the Hasse principle for a wide new family of varieties of the form f(t) = NK/Q(x) ̸= 0, where f is a polynomial with integer coefficients and NK/Q denotes the norm\r\nform associated to a number field K. Our results cover products of arbitrarily many linear, quadratic or cubic factors, and generalise an argument of Irving [69], which makes use of the beta sieve of Rosser and Iwaniec. We also demonstrate how our main sieve results can be applied to treat new cases of a conjecture of Harpaz and Wittenberg on locally split values of polynomials over number fields, and discuss consequences for rational points in fibrations.\r\nIn the second question, about the density of solutions, one defines a height function and seeks to estimate asymptotically the number of points of height bounded by B as B → ∞. Traditionally, one either counts rational points, or\r\nintegral points with respect to a suitable model. However, in this thesis, we study an emerging area of interest in Arithmetic geometry known as Campana points, which in some sense interpolate between rational and integral points.\r\nMore precisely, we count the number of nonzero integers z1, z2, z3 such that gcd(z1, z2, z3) = 1, and z1, z2, z3, z1 + z2 + z3 are all squareful and bounded by B. Using the circle method, we obtain an asymptotic formula which agrees in\r\nthe power of B and log B with a bold new generalisation of Manin’s conjecture to the setting of Campana points, recently formulated by Pieropan, Smeets, Tanimoto and Várilly-Alvarado [96]. However, in this thesis we also provide the first known counterexamples to leading constant predicted by their conjecture. " acknowledgement: I acknowledge the received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska Curie Grant Agreement No. 665385. alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Alec L full_name: Shute, Alec L id: 440EB050-F248-11E8-B48F-1D18A9856A87 last_name: Shute orcid: 0000-0002-1812-2810 citation: ama: 'Shute AL. Existence and density problems in Diophantine geometry: From norm forms to Campana points. 2022. doi:10.15479/at:ista:12072' apa: 'Shute, A. L. (2022). Existence and density problems in Diophantine geometry: From norm forms to Campana points. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12072' chicago: 'Shute, Alec L. “Existence and Density Problems in Diophantine Geometry: From Norm Forms to Campana Points.” Institute of Science and Technology Austria, 2022. https://doi.org/10.15479/at:ista:12072.' ieee: 'A. L. Shute, “Existence and density problems in Diophantine geometry: From norm forms to Campana points,” Institute of Science and Technology Austria, 2022.' ista: 'Shute AL. 2022. Existence and density problems in Diophantine geometry: From norm forms to Campana points. Institute of Science and Technology Austria.' mla: 'Shute, Alec L. Existence and Density Problems in Diophantine Geometry: From Norm Forms to Campana Points. Institute of Science and Technology Austria, 2022, doi:10.15479/at:ista:12072.' short: 'A.L. Shute, Existence and Density Problems in Diophantine Geometry: From Norm Forms to Campana Points, Institute of Science and Technology Austria, 2022.' date_created: 2022-09-08T21:53:03Z date_published: 2022-09-08T00:00:00Z date_updated: 2023-02-21T16:37:35Z day: '08' ddc: - '512' degree_awarded: PhD department: - _id: GradSch - _id: TiBr doi: 10.15479/at:ista:12072 ec_funded: 1 file: - access_level: open_access checksum: bf073344320e05d92c224786cec2e92d content_type: application/pdf creator: ashute date_created: 2022-09-08T21:50:34Z date_updated: 2022-09-08T21:50:34Z file_id: '12073' file_name: Thesis_final_draft.pdf file_size: 1907386 relation: main_file success: 1 - access_level: closed checksum: b054ac6baa09f70e8235403a4abbed80 content_type: application/octet-stream creator: ashute date_created: 2022-09-08T21:50:42Z date_updated: 2022-09-12T11:24:21Z file_id: '12074' file_name: athesis.tex file_size: 495393 relation: source_file - access_level: closed checksum: 0a31e905f1cff5eb8110978cc90e1e79 content_type: application/x-zip-compressed creator: ashute date_created: 2022-09-09T12:05:00Z date_updated: 2022-09-12T11:24:21Z file_id: '12078' file_name: qfcjsfmtvtbfrjjvhdzrnqxfvgjvxtbf.zip file_size: 944534 relation: source_file file_date_updated: 2022-09-12T11:24:21Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '208' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-023-7 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '12076' relation: part_of_dissertation status: public - id: '12077' relation: part_of_dissertation status: public status: public supervisor: - first_name: Timothy D full_name: Browning, Timothy D id: 35827D50-F248-11E8-B48F-1D18A9856A87 last_name: Browning orcid: 0000-0002-8314-0177 title: 'Existence and density problems in Diophantine geometry: From norm forms to Campana points' 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: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2022' ... --- _id: '11777' abstract: - lang: eng text: "In this dissertation we study coboundary expansion of simplicial complex with a view of giving geometric applications.\r\nOur main novel tool is an equivariant version of Gromov's celebrated Topological Overlap Theorem. The equivariant topological overlap theorem leads to various geometric applications including a quantitative non-embeddability result for sufficiently thick buildings (which partially resolves a conjecture of Tancer and Vorwerk) and an improved lower bound on the pair-crossing number of (bounded degree) expander graphs. Additionally, we will give new proofs for several known lower bounds for geometric problems such as the number of Tverberg partitions or the crossing number of complete bipartite graphs.\r\nFor the aforementioned applications one is naturally lead to study expansion properties of joins of simplicial complexes. In the presence of a special certificate for expansion (as it is the case, e.g., for spherical buildings), the join of two expanders is an expander. On the flip-side, we report quite some evidence that coboundary expansion exhibits very non-product-like behaviour under taking joins. For instance, we exhibit infinite families of graphs $(G_n)_{n\\in \\mathbb{N}}$ and $(H_n)_{n\\in\\mathbb{N}}$ whose join $G_n*H_n$ has expansion of lower order than the product of the expansion constant of the graphs. Moreover, we show an upper bound of $(d+1)/2^d$ on the normalized coboundary expansion constants for the complete multipartite complex $[n]^{*(d+1)}$ (under a mild divisibility condition on $n$).\r\nVia the probabilistic method the latter result extends to an upper bound of $(d+1)/2^d+\\varepsilon$ on the coboundary expansion constant of the spherical building associated with $\\mathrm{PGL}_{d+2}(\\mathbb{F}_q)$ for any $\\varepsilon>0$ and sufficiently large $q=q(\\varepsilon)$. This disproves a conjecture of Lubotzky, Meshulam and Mozes -- in a rather strong sense.\r\nBy improving on existing lower bounds we make further progress towards closing the gap between the known lower and upper bounds on the coboundary expansion constants of $[n]^{*(d+1)}$. The best improvements we achieve using computer-aided proofs and flag algebras. The exact value even for the complete $3$-partite $2$-dimensional complex $[n]^{*3}$ remains unknown but we are happy to conjecture a precise value for every $n$. %Moreover, we show that a previously shown lower bound on the expansion constant of the spherical building associated with $\\mathrm{PGL}_{2}(\\mathbb{F}_q)$ is not tight.\r\nIn a loosely structured, last chapter of this thesis we collect further smaller observations related to expansion. We point out a link between discrete Morse theory and a technique for showing coboundary expansion, elaborate a bit on the hardness of computing coboundary expansion constants, propose a new criterion for coboundary expansion (in a very dense setting) and give one way of making the folklore result that expansion of links is a necessary condition for a simplicial complex to be an expander precise." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Pascal full_name: Wild, Pascal id: 4C20D868-F248-11E8-B48F-1D18A9856A87 last_name: Wild citation: ama: Wild P. High-dimensional expansion and crossing numbers of simplicial complexes. 2022. doi:10.15479/at:ista:11777 apa: Wild, P. (2022). High-dimensional expansion and crossing numbers of simplicial complexes. Institute of Science and Technology. https://doi.org/10.15479/at:ista:11777 chicago: Wild, Pascal. “High-Dimensional Expansion and Crossing Numbers of Simplicial Complexes.” Institute of Science and Technology, 2022. https://doi.org/10.15479/at:ista:11777. ieee: P. Wild, “High-dimensional expansion and crossing numbers of simplicial complexes,” Institute of Science and Technology, 2022. ista: Wild P. 2022. High-dimensional expansion and crossing numbers of simplicial complexes. Institute of Science and Technology. mla: Wild, Pascal. High-Dimensional Expansion and Crossing Numbers of Simplicial Complexes. Institute of Science and Technology, 2022, doi:10.15479/at:ista:11777. short: P. Wild, High-Dimensional Expansion and Crossing Numbers of Simplicial Complexes, Institute of Science and Technology, 2022. date_created: 2022-08-10T15:51:19Z date_published: 2022-08-11T00:00:00Z date_updated: 2023-06-22T09:56:36Z day: '11' ddc: - '500' - '516' - '514' degree_awarded: PhD department: - _id: GradSch - _id: UlWa doi: 10.15479/at:ista:11777 ec_funded: 1 file: - access_level: open_access checksum: f5f3af1fb7c8a24b71ddc88ad7f7c5b4 content_type: text/x-python creator: pwild date_created: 2022-08-10T15:34:04Z date_updated: 2022-08-10T15:34:04Z description: Code for computer-assisted proofs in Section 8.4.7 in Thesis file_id: '11780' file_name: flags.py file_size: 16828 relation: supplementary_material - access_level: open_access checksum: 1f7c12dfe3bdaa9b147e4fbc3d34e3d5 content_type: text/x-c++src creator: pwild date_created: 2022-08-10T15:34:10Z date_updated: 2022-08-10T15:34:10Z description: Code for proof of Lemma 8.20 in Thesis file_id: '11781' file_name: lowerbound.cpp file_size: 12226 relation: supplementary_material - access_level: open_access checksum: 4cf81455c49e5dec3b9b2e3980137eeb content_type: text/x-python creator: pwild date_created: 2022-08-10T15:34:17Z date_updated: 2022-08-10T15:34:17Z description: Code for proof of Proposition 7.9 in Thesis file_id: '11782' file_name: upperbound.py file_size: 3240 relation: supplementary_material - access_level: open_access checksum: 4e96575b10cbe4e0d0db2045b2847774 content_type: application/pdf creator: pwild date_created: 2022-08-11T16:08:33Z date_updated: 2022-08-11T16:08:33Z file_id: '11809' file_name: finalthesisPascalWildPDFA.pdf file_size: 5086282 relation: main_file title: High-Dimensional Expansion and Crossing Numbers of Simplicial Complexes - access_level: closed checksum: 92d94842a1fb6dca5808448137573b2e content_type: application/zip creator: pwild date_created: 2022-08-11T16:09:19Z date_updated: 2022-08-11T16:09:19Z file_id: '11810' file_name: ThesisSubmission.zip file_size: 18150068 relation: source_file file_date_updated: 2022-08-11T16:09:19Z has_accepted_license: '1' language: - iso: eng month: '08' oa: 1 oa_version: Published Version page: '170' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-021-3 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology status: public supervisor: - first_name: Uli full_name: Wagner, Uli id: 36690CA2-F248-11E8-B48F-1D18A9856A87 last_name: Wagner orcid: 0000-0002-1494-0568 title: High-dimensional expansion and crossing numbers of simplicial complexes type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2022' ...