--- OA_place: publisher OA_type: gold _id: '18515' abstract: - lang: eng text: "Understanding the role of evolutionary processes in shaping genetic variation has been a\r\nprimary goal in evolutionary genetics. In this regard, a key question is how genetically\r\ndistinct populations evolve in the face of gene flow, thereby generating genetic and\r\nphenotypic divergence and reproductive isolation (RI). This requires quantifying the role\r\nand relative contributions of prezygotic and postzygotic isolating mechanisms on the\r\nreduction of gene exchange between populations, and identifying regions in the genome\r\nthat mediate RI, which is often polygenic. Further, this needs distinguishing neutral and\r\nselected regions in the genome, and discerning how selection influences patterns of neutral\r\ndivergence.\r\nPopulation structure, defined as any deviation from panmixia, such as geographic distribution, movement and mating patterns of individuals, influences how genetic variation is\r\nstructured in space and shapes the neutral null model. Availability of large scale spatial\r\ngenomic datasets now enables us to detect signatures of population structure in genetic\r\ndata and infer population genetic parameters. Such inferences are crucial and have wide\r\napplications in biodiversity, conservation genetics, population management and medical\r\ngenetics. However, inferences are based on assumptions that do not always match the\r\ncomplex reality, thus leading to erroneous conclusions. Moreover, the role and interaction\r\nof heterogeneous population density and dispersal, which are ubiquitous in nature, has\r\nbeen challenging to study owing to their mathematical complexity. In such scenarios,\r\nfeedback between theory, data and simulations can prove to be useful.\r\nIn this thesis, I examine the effect of population structure on neutral genetic variation\r\nand barriers to gene exchange in hybridising populations, thereby bridging together the\r\nfields of spatial population genetics and speciation.\r\nDespite being a key concept in speciation, reproductive isolation (RI) lacks a quantitative\r\ndefinition and has been used and measured differently across different fields. Chapter 2\r\ngives a quantitative definition of RI, in terms of the effect of genetic differences on gene\r\nflow. We give analytical predictions for RI in a range of scenarios, in terms of effective migration rates for discrete populations and barrier strength for continuous populations.\r\nIn addition to this, we discuss current measures of RI and their limitations, and propose\r\nthe need for new measures that combine organismal and genetic perspectives of RI.\r\nIn chapter 3, I examine the combined effect of assortative mating, sexual selection\r\nand viability selection on RI. For this, we consider a polygenic ‘magic’ trait under a\r\nmainland-island model. We obtain novel theoretical predictions for molecular divergence\r\nin terms of effective migration rates, which bears a simple relationship to measurable\r\nfitness components of migrants and various early generation hybrids. We explore the\r\nconditions under which local adaptation can be maintained despite maladaptive gene flow\r\nand quantify the relative contributions of viability and sexual selection to genome-wide\r\nbarriers to gene flow.\r\nThe next two chapters of the thesis focus on a hybrid zone of Antirrhinum majus that\r\nconsist of two subspecies- the magenta flowered A. m. pseudomajus and the yellow\r\nflowered A.m. striatum. Previous studies have suggested that flower colour is target of\r\npollinator mediated selection and is influenced only by few genes. While these regions\r\nshow high genetic differentiation between the subspecies, the rest of the genome is seen\r\nto be well mixed. Chapter 4 examines the effects of heterogeneous population density\r\nand leptokurtic dispersal on isolation by distance and the distribution of heterozygosity\r\nby focusing on non-flower colour markers.\r\nChapter 5 analyses cline shapes and associations among 6 focal flower colour markers to\r\nunderstand how selection and dispersal maintain this hybrid zone. We see sharp coincident\r\nstepped clines at all loci and positive associations throughout the hybrid zone, contrary to\r\nthe expected patterns from diffusive gene flow. With a novel scheme of inferring dispersal\r\ncombined with multilocus simulations, we show that stepped clines do not reflect genetic\r\nbarriers to gene flow, but are rather a result of long-distance migration. This framework\r\nallows us to get realistic estimates gene flow and selection and shows how traditional cline\r\nanalysis may lead to inaccurate conclusions when assumptions of the theory are not met.\r\nOverall, this thesis investigates how different features of population structure leave\r\ndetectable signatures in genetic variation, namely in patterns of isolation by distance,\r\nlinkage disequilibrium and genetic divergence. It also highlights how effective migration\r\nrates provide useful way of analysing polygenic architectures and shed new light into\r\nhybrid zones. In doing so, I identify scenarios when simple models become insufficient\r\nand suggest possibe directions by combining genetic data with simulations." acknowledged_ssus: - _id: ScienComp acknowledgement: "I also acknowledge the funding agencies Marie Curie COFUND Doctoral Fellowship,\r\nAustrian Science Fund FWF (grant P32166) and ERC (grant PR1000ERC02) for financially\r\nsupporting my research over the years." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Parvathy full_name: Surendranadh, Parvathy id: 455235B8-F248-11E8-B48F-1D18A9856A87 last_name: Surendranadh orcid: 0000-0001-6395-386X citation: ama: Surendranadh P. Effect of population structure on neutral genetic variation and barriers to gene exchange. 2024. doi:10.15479/at:ista:18515 apa: Surendranadh, P. (2024). Effect of population structure on neutral genetic variation and barriers to gene exchange. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18515 chicago: Surendranadh, Parvathy. “Effect of Population Structure on Neutral Genetic Variation and Barriers to Gene Exchange.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18515. ieee: P. Surendranadh, “Effect of population structure on neutral genetic variation and barriers to gene exchange,” Institute of Science and Technology Austria, 2024. ista: Surendranadh P. 2024. Effect of population structure on neutral genetic variation and barriers to gene exchange. Institute of Science and Technology Austria. mla: Surendranadh, Parvathy. Effect of Population Structure on Neutral Genetic Variation and Barriers to Gene Exchange. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18515. short: P. Surendranadh, Effect of Population Structure on Neutral Genetic Variation and Barriers to Gene Exchange, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-11-06T21:25:37Z date_published: 2024-11-07T00:00:00Z date_updated: 2026-04-07T12:56:52Z day: '07' ddc: - '576' degree_awarded: PhD department: - _id: GradSch - _id: NiBa doi: 10.15479/at:ista:18515 file: - access_level: open_access checksum: c32cf7bc75748d9c551d8eb70178bbec content_type: application/pdf creator: psurendr date_created: 2024-11-07T10:59:29Z date_updated: 2024-11-07T10:59:29Z file_id: '18519' file_name: PhD_Thesis__Parvathy_071124_PDFA.pdf file_size: 37019760 relation: main_file success: 1 - access_level: closed checksum: 4417e02d54084d89e75734e18caaa96d content_type: application/zip creator: psurendr date_created: 2024-11-07T10:59:42Z date_updated: 2024-11-07T10:59:42Z file_id: '18520' file_name: PhD Thesis- Parvathy_071124.zip file_size: 41198857 relation: source_file file_date_updated: 2024-11-07T10:59:42Z 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: '219' project: - _id: 05959E1C-7A3F-11EA-A408-12923DDC885E grant_number: P32166 name: Snapdragon Speciation - _id: bd6958e0-d553-11ed-ba76-86eba6a76c00 grant_number: '101055327' name: Understanding the evolution of continuous genomes publication_identifier: issn: - 2663-337X 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: Effect of population structure on neutral genetic variation and barriers to gene exchange 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: '2024' ... --- OA_place: publisher _id: '18568' abstract: - lang: eng text: "Locomotion is ubiquitous in the animal kingdom because an animal's survival depends on its ability to navigate its environment to find food, avoid predators and locate potential mates. These behaviours require control mechanisms that can extract information from the environment, particularly visual cues. Selective evolutionary pressures have thus refined such visuomotor transformations in a species-specific manner to meet the specific ecological and ethological challenges of each organism. However, a common challenge across organisms as visual information processing\r\nbecomes increasingly detailed is the mechanisms required to synthesise disparate pieces of information into a coherent percept or unified picture of the world. In this thesis, I investigate how disparate visual information is combined in the brain of Drosophila melanogaster to effectively guide locomotion.\r\nFor this, I first designed and built a behavioural setup to record locomotion and present visual stimuli to freely-walking fruit flies in a closed-loop manner. This setup allowed the investigation of innate visually-guided behaviours, including the optomotor reflex and courtship.\r\nSecond, taking advantage of my system I investigated the optomotor response, a reflexive visual stabilisation behaviour in which flies turn in the direction of global motion to minimise retinal slip. This behaviour is thought to be mediated by Lobula plate tangential cells (LPTCs); a complex network of optic-flow-sensitive neurons essential for self-motion estimation. Using a novel genetic mutant, I demonstrate that electrical coupling between two LPTC subtypes, contralateral HS and H2 neurons, regulates the balance between smooth optomotor turning and saccadic anti-optomotor responses. These findings underscore the critical role of binocular motion cue integration in guiding course control. Finally, I developed a novel behavioural paradigm in which a sexually aroused male fruit fly is presented with an optomotor distractor. This setup creates competition between two visual behaviours, courtship tracking and the optomotor response, enabling me to explore how the visual system resolves this conflict. In this setting, males\r\nengaged in courtship selectively suppress their optomotor response based on the female's location. Furthermore, when this experiment is replicated with an “artificial female”, optogenetically aroused males alternate between tracking and optomotor responses. The probability and dynamics of this switching are determined by the relative strengths of the two competing stimuli. In summary, the results presented in this thesis explore two mechanisms – integration and competition - through which visual information is combined in the brain of the fruit fly to drive locomotion." acknowledged_ssus: - _id: M-Shop acknowledgement: I am incredibly thankful for the outstanding support provided by ISTA, especially the Machine Shop team, who made conducting research much easier and more efficient. I am also grateful for the funding provided by European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie programme (665385) and The German Research Foundation grant DFG (SPP2205) “Evolutionary optimization of neuronal processing”. alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Roshan K full_name: Satapathy, Roshan K id: 46046B7A-F248-11E8-B48F-1D18A9856A87 last_name: Satapathy orcid: 0009-0006-2974-5075 citation: ama: Satapathy RK. Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster. 2024. doi:10.15479/at:ista:18568 apa: Satapathy, R. K. (2024). Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18568 chicago: Satapathy, Roshan K. “Mechanisms of Visual Integration and Competition in Innate Behaviours in Drosophila Melanogaster.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18568. ieee: R. K. Satapathy, “Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster,” Institute of Science and Technology Austria, 2024. ista: Satapathy RK. 2024. Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster. Institute of Science and Technology Austria. mla: Satapathy, Roshan K. Mechanisms of Visual Integration and Competition in Innate Behaviours in Drosophila Melanogaster. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18568. short: R.K. Satapathy, Mechanisms of Visual Integration and Competition in Innate Behaviours in Drosophila Melanogaster, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-11-19T12:34:30Z date_published: 2024-11-20T00:00:00Z date_updated: 2026-04-07T13:00:36Z day: '20' ddc: - '573' degree_awarded: PhD department: - _id: GradSch - _id: MaJö doi: 10.15479/at:ista:18568 ec_funded: 1 file: - access_level: open_access checksum: 340f2bfe882c8a85e11ec0687ca15f5e content_type: application/pdf creator: rsatapat date_created: 2024-11-19T12:39:55Z date_updated: 2024-11-19T12:39:55Z file_id: '18570' file_name: Roshan PhD thesis-Final.pdf file_size: 10960975 relation: main_file success: 1 - access_level: closed checksum: 0f846fce60d6ea511e07f77eff59a6a1 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: rsatapat date_created: 2024-11-19T12:46:47Z date_updated: 2024-12-13T10:27:25Z file_id: '18571' file_name: Roshan PhD thesis-Final.docx file_size: 36695917 relation: source_file file_date_updated: 2024-12-13T10:27:25Z has_accepted_license: '1' language: - iso: eng license: https://creativecommons.org/licenses/by-sa/4.0/ month: '11' oa: 1 oa_version: Published Version page: '114' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - 978-3-99078-047-3 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '18444' relation: part_of_dissertation status: public 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: Mechanisms of visual integration and competition in innate behaviours in Drosophila melanogaster tmp: image: /images/cc_by_sa.png legal_code_url: https://creativecommons.org/licenses/by-sa/4.0/legalcode name: Creative Commons Attribution-ShareAlike 4.0 International Public License (CC BY-SA 4.0) short: CC BY-SA (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '18674' abstract: - lang: eng text: Mapping the complex and dense arrangement of cells and their connectivity in brain tissue requires volumetric imaging at nanoscale spatial resolution. While light microscopy excels at visualizing specific molecules and individual cells, achieving dense, synapse-level circuit reconstruction has not been possible with any light microscopy technique. Thus, the goal of my work was to develop image and data analysis pipelines for brain tissue visualization and reconstruction with light microscopy. To achieve dense circuit reconstruction with single-synapse resolution, I developed both conventional and deep-learning-based synapse detection algorithms, as well as connectivity analysis pipelines that integrate synapse detection with volumetric segmentation of brain tissue. acknowledged_ssus: - _id: Bio alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Julia full_name: Lyudchik, Julia id: 46E28B80-F248-11E8-B48F-1D18A9856A87 last_name: Lyudchik citation: ama: Lyudchik J. Image analysis for brain tissue reconstruction with super-resolution light microscopy. 2024. doi:10.15479/at:ista:18674 apa: Lyudchik, J. (2024). Image analysis for brain tissue reconstruction with super-resolution light microscopy. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18674 chicago: Lyudchik, Julia. “Image Analysis for Brain Tissue Reconstruction with Super-Resolution Light Microscopy.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18674. ieee: J. Lyudchik, “Image analysis for brain tissue reconstruction with super-resolution light microscopy,” Institute of Science and Technology Austria, 2024. ista: Lyudchik J. 2024. Image analysis for brain tissue reconstruction with super-resolution light microscopy. Institute of Science and Technology Austria. mla: Lyudchik, Julia. Image Analysis for Brain Tissue Reconstruction with Super-Resolution Light Microscopy. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18674. short: J. Lyudchik, Image Analysis for Brain Tissue Reconstruction with Super-Resolution Light Microscopy, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-12-18T14:24:43Z date_published: 2024-12-18T00:00:00Z date_updated: 2026-04-14T08:34:35Z day: '18' ddc: - '004' degree_awarded: PhD department: - _id: GradSch - _id: JoDa doi: 10.15479/at:ista:18674 ec_funded: 1 file: - access_level: open_access checksum: 1b42b8073e2bc09fc504da52372248c1 content_type: application/pdf creator: jlyudchi date_created: 2024-12-18T14:17:34Z date_updated: 2024-12-18T14:17:34Z file_id: '18675' file_name: 18122024_PhDthesis_corrected_final_pdfa.pdf file_size: 160536833 relation: main_file success: 1 - access_level: closed checksum: b4da84624060745519723698f7ddf54b content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: jlyudchi date_created: 2024-12-18T14:21:06Z date_updated: 2024-12-18T14:41:53Z file_id: '18676' file_name: 18122024_PhDthesis_corrected_final_JL_markup.docx file_size: 99172203 relation: source_file file_date_updated: 2024-12-18T14:41:53Z has_accepted_license: '1' language: - iso: eng license: https://creativecommons.org/licenses/by-nc-nd/4.0/ month: '12' oa: 1 oa_version: Published Version page: '217' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: isbn: - ' 978-3-99078-051-0' issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11160' relation: part_of_dissertation status: public - id: '18677' relation: part_of_dissertation status: public - id: '13267' relation: part_of_dissertation status: public - id: '14257' 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: Image analysis for brain tissue reconstruction with super-resolution light microscopy 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: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_embargo: '20' OA_place: publisher _id: '18681' acknowledged_ssus: - _id: Bio - _id: PreCl - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Mojtaba full_name: Tavakoli, Mojtaba id: 3A0A06F4-F248-11E8-B48F-1D18A9856A87 last_name: Tavakoli orcid: 0000-0002-7667-6854 citation: ama: 'Tavakoli M. Developing molecular and structural tools for studying brain architecture with super resolution expansion microscopy. LICONN: Molecularly-informed connectomics reconstruction with light microscopy. 2024. doi:10.15479/at:ista:18681' apa: 'Tavakoli, M. (2024). Developing molecular and structural tools for studying brain architecture with super resolution expansion microscopy. LICONN: Molecularly-informed connectomics reconstruction with light microscopy. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18681' chicago: 'Tavakoli, Mojtaba. “Developing Molecular and Structural Tools for Studying Brain Architecture with Super Resolution Expansion Microscopy. LICONN: Molecularly-Informed Connectomics Reconstruction with Light Microscopy.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18681.' ieee: 'M. Tavakoli, “Developing molecular and structural tools for studying brain architecture with super resolution expansion microscopy. LICONN: Molecularly-informed connectomics reconstruction with light microscopy,” Institute of Science and Technology Austria, 2024.' ista: 'Tavakoli M. 2024. Developing molecular and structural tools for studying brain architecture with super resolution expansion microscopy. LICONN: Molecularly-informed connectomics reconstruction with light microscopy. Institute of Science and Technology Austria.' mla: 'Tavakoli, Mojtaba. Developing Molecular and Structural Tools for Studying Brain Architecture with Super Resolution Expansion Microscopy. LICONN: Molecularly-Informed Connectomics Reconstruction with Light Microscopy. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18681.' short: 'M. Tavakoli, Developing Molecular and Structural Tools for Studying Brain Architecture with Super Resolution Expansion Microscopy. LICONN: Molecularly-Informed Connectomics Reconstruction with Light Microscopy, Institute of Science and Technology Austria, 2024.' corr_author: '1' date_created: 2024-12-19T02:30:39Z date_published: 2024-12-20T00:00:00Z date_updated: 2026-04-07T12:56:37Z day: '20' ddc: - '600' - '570' degree_awarded: PhD department: - _id: GradSch - _id: JoDa doi: 10.15479/at:ista:18681 file: - access_level: closed checksum: b61651d417cafddd740a8528f46068c5 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: mtavakol date_created: 2024-12-20T10:23:17Z date_updated: 2024-12-20T10:31:37Z file_id: '18699' file_name: Thesis_Mojtaba Tavakoli_.docx file_size: 118593521 relation: source_file - access_level: closed checksum: c80bcfd1a34c23afc3538052325283e5 content_type: application/pdf creator: mtavakol date_created: 2024-12-20T10:25:12Z date_updated: 2024-12-20T10:25:12Z embargo: 2026-08-01 embargo_to: open_access file_id: '18700' file_name: Thesis_Mojtaba Tavakoli_.pdf file_size: 63885521 relation: main_file file_date_updated: 2024-12-20T10:31:37Z has_accepted_license: '1' language: - iso: eng month: '12' oa_version: Published Version page: '230' project: - _id: 6285a163-2b32-11ec-9570-8e204ca2dba5 grant_number: '26137' name: Studying Organelle Structure and Function at Nanoscale Resolution with Expansion Microscopy - _id: 26AA4EF2-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: W1232-B24 name: Molecular Drug Targets publication_identifier: isbn: - 978-3-99078-048-0 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11160' relation: part_of_dissertation status: public - id: '18688' relation: part_of_dissertation status: public - id: '18677' relation: part_of_dissertation status: public - id: '18689' 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: 'Developing molecular and structural tools for studying brain architecture with super resolution expansion microscopy. LICONN: Molecularly-informed connectomics reconstruction with light microscopy' 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: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '18766' abstract: - lang: eng text: Poxviruses are large pleomorphic double-stranded DNA viruses that include well known members such as variola virus, the causative agent of smallpox, Mpox virus, as well as Vaccinia virus (VACV), which serves as a vaccination strain for formerly mentioned viruses. VACV is a valuable model for studying large pleomorphic DNA viruses in general and poxviruses specifically, as many features, such as core morphology and structural proteins, are well conserved within this family. Despite decades of research, our understanding of the structural components and proteins that comprise the poxvirus core in mature virions remains limited. Although major core proteins were identified via indirect experimental evidence, the core's complexity, with its large size, structure and number of involved proteins, has hindered efforts to achieve high-resolution insights and to define the roles of the individual proteins. The specific protein composition of the core's individual layers, including the palisade layer and the inner core wall, has remained unclear. In this study, we have merged multiple approaches, including single particle cryo electron microscopy of purified virus cores, cryo-electron tomography and subtomogram averaging of mature virions and molecular modeling to elucidate the structural determinants of the VACV core. Due to the lack of experimentally derived structures, either in situ or reconstituted in vitro, we used Alphafold to predict models of the putative major core protein candidates, A10, 23k, A3, A4, and L4. Our results show that the VACV core is composed of several layers with varying local symmetries, forming more intricate interactions than observed previously. This allowed us to identify several molecular building blocks forming the viral core lattice. In particular, we identified trimers of protein A10 as a major core structure that forms the palisade layer of the viral core. Additionally, we revealed that six petals of a flower shaped core pore within the core wall are composed of A10 trimers. Furthermore, we obtained a cryo-EM density for the inner core wall that could potentially accommodate an A3 dimer. Integrating descriptions of protein interactions from previous studies enabled us to provide a detailed structural model of the poxvirus core wall, and our findings indicate that the interactions within A10 trimers are likely consistent across orthopox- and parapoxviruses. This combined application of cryo-SPA and cryo-ET can help overcome obstacles in studying complex virus structures in the future, including their key assembly proteins, interactions, and the formation into a core lattice. Our work provides important fundamental new insights into poxvirus core architecture, also considering the recent re-emergence of poxviruses. acknowledged_ssus: - _id: EM-Fac - _id: LifeSc - _id: ScienComp acknowledgement: "This work was funded by the Austrian Science Fund (FWF) grant P31445 and ISTA. I\r\nwould like to express my gratitude to the Scientific Service Units, particularly the Lab\r\nSupport Facility, the Scientific Computing Facility and the Electron Microscopy Facility\r\nfor their tremendous support. I want to especially thank Alois for assisting me with the\r\ninstallation of countless new software and for troubleshooting cluster issues. A special\r\nthanks goes to Valentin for his outstanding support in cryo-EM data acquisition and\r\nhis ongoing help in improving the process to ensure that I obtained the best possible\r\ndata from my sample." alternative_title: - ISTA thesis article_processing_charge: No author: - first_name: Julia full_name: Datler, Julia id: 3B12E2E6-F248-11E8-B48F-1D18A9856A87 last_name: Datler orcid: 0000-0002-3616-8580 citation: ama: Datler J. Elucidating the structural determinants of the poxvirus core using multi-modal cryo-EM. 2024. doi:10.15479/at:ista:18766 apa: Datler, J. (2024). Elucidating the structural determinants of the poxvirus core using multi-modal cryo-EM. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18766 chicago: Datler, Julia. “Elucidating the Structural Determinants of the Poxvirus Core Using Multi-Modal Cryo-EM.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18766. ieee: J. Datler, “Elucidating the structural determinants of the poxvirus core using multi-modal cryo-EM,” Institute of Science and Technology Austria, 2024. ista: Datler J. 2024. Elucidating the structural determinants of the poxvirus core using multi-modal cryo-EM. Institute of Science and Technology Austria. mla: Datler, Julia. Elucidating the Structural Determinants of the Poxvirus Core Using Multi-Modal Cryo-EM. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18766. short: J. Datler, Elucidating the Structural Determinants of the Poxvirus Core Using Multi-Modal Cryo-EM, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2025-01-07T10:23:12Z date_published: 2024-12-30T00:00:00Z date_updated: 2026-04-07T12:59:44Z day: '30' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: FlSc doi: 10.15479/at:ista:18766 file: - access_level: closed checksum: 3e51cab327c754045c3d29c1a50cc9a9 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: jstanger date_created: 2025-01-07T12:15:11Z date_updated: 2025-01-07T12:15:11Z file_id: '18769' file_name: PhD_thesis_Julia_Datler.docx file_size: 38814932 relation: source_file - access_level: open_access checksum: 22fabe5b97950bf852212f6edb555173 content_type: application/pdf creator: jstanger date_created: 2025-01-07T12:15:14Z date_updated: 2025-01-07T12:15:14Z file_id: '18770' file_name: PhD_thesis_Julia_Datler.pdf file_size: 12044865 relation: main_file success: 1 file_date_updated: 2025-01-07T12:15:14Z has_accepted_license: '1' keyword: - cryo-EM - cryo-ET - cryo-SPA - Structural Virology - Poxvirus - Vaccinia Virus - Structural Biology language: - iso: eng month: '12' oa: 1 oa_version: Published Version page: '106' project: - _id: 26736D6A-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P31445 name: Structural conservation and diversity in retroviral capsid publication_identifier: isbn: - 978-3-99078-049-7 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '12334' relation: part_of_dissertation status: public - id: '14979' 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: Elucidating the structural determinants of the poxvirus core using multi-modal cryo-EM 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: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '17208' abstract: - lang: eng text: "Can current quantum computers provide a speedup over their classical counterparts for some kinds of problems? In this thesis, with a focus on ground state search/preparation, we address some of the challenges that both quantum annealing and variational quantum algorithms suffer from, hindering any possible practical speedup in comparison to the best classical counterparts. \r\n\r\nIn the first part of the thesis, we study the performance of quantum annealing for solving a particular combinatorial optimization problem called 3-XOR satisfability (3-XORSAT). The classical problem is mapped into a ground state search of a 3-local classical Hamiltonian $H_C$. We consider how modifying the initial problem, by adding more interaction terms to the corresponding Hamiltonian, leads to the emergence of a first-order phase transition during the annealing process. This phenomenon causes the total annealing duration, $T$, required to prepare the ground state of $H_C$ with a high probability to increase exponentially with the size of the problem. Our findings indicate that with the growing complexity of problem instances, the likelihood of encountering first-order phase transitions also increases, making quantum annealing an impractical solution for these types of combinatorial optimization problems.\r\n\r\nIn the second part, we focus on the problem of barren plateaus in generic variational quantum algorithms. Barren plateaus correspond to flat regions in the parameter space where the gradient of the cost function is zero in expectation, and with the variance decaying exponentially with the system size, thus obstructing an efficient parameter optimization. We propose an algorithm to circumvent Barren Plateaus by monitoring the entanglement entropy of k-local reduced density matrices, alongside a method for estimating entanglement entropy via classical shadow tomography. We illustrate the approach with the paradigmatic example of the variational quantum eigensolver, and show that our algorithm effectively avoids barren plateaus in the initialization as well as during the optimization stage. \r\n\r\nLastly, in the last two Chapters of this thesis, we focus on the quantum approximate optimization algorithm (QAOA), originally introduced as an algorithm for solving generic combinatorial optimization problems in near-term quantum devices. Specifically, we focus on how to develop rigorous initialization strategies with guarantee improvement. Our motivation for this study lies in that for random initialization, the optimization typically leads to local minima with poor performance. Our main result corresponds to the analytical construction of index-1 saddle points or transition states, stationary points with a single direction of descent, as a tool for systematically exploring the QAOA optimization landscape. This leads us to propose a novel greedy parameter initialization strategy that guarantees for the energy to decrease with an increasing number of circuit layers. Furthermore, with precise estimates for the negative Hessian eigenvalue and its eigenvector, we establish a lower bound for energy improvement following a QAOA iteration." acknowledged_ssus: - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - 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 citation: ama: Medina Ramos RA. Exploring the optimization landscape of variational quantum algorithms. 2024. doi:10.15479/at:ista:17208 apa: Medina Ramos, R. A. (2024). Exploring the optimization landscape of variational quantum algorithms. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17208 chicago: Medina Ramos, Raimel A. “Exploring the Optimization Landscape of Variational Quantum Algorithms.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17208. ieee: R. A. Medina Ramos, “Exploring the optimization landscape of variational quantum algorithms,” Institute of Science and Technology Austria, 2024. ista: Medina Ramos RA. 2024. Exploring the optimization landscape of variational quantum algorithms. Institute of Science and Technology Austria. mla: Medina Ramos, Raimel A. Exploring the Optimization Landscape of Variational Quantum Algorithms. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17208. short: R.A. Medina Ramos, Exploring the Optimization Landscape of Variational Quantum Algorithms, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-07-09T09:14:24Z date_published: 2024-07-09T00:00:00Z date_updated: 2026-04-07T12:43:22Z day: '09' ddc: - '539' degree_awarded: PhD department: - _id: GradSch - _id: MaSe doi: 10.15479/at:ista:17208 ec_funded: 1 file: - access_level: closed checksum: 6f45273d04f4418bc2adc018baed0525 content_type: application/zip creator: rmedinar date_created: 2024-07-09T09:21:44Z date_updated: 2024-07-10T11:34:09Z file_id: '17212' file_name: Raimel_Thesis-Final.zip file_size: '14218691' relation: source_file - access_level: open_access checksum: 6724a95bec772dbabc0111b9f08a805e content_type: application/pdf creator: rmedinar date_created: 2024-07-17T09:23:24Z date_updated: 2024-07-17T09:23:24Z file_id: '17275' file_name: Raimel_Thesis-20_pdfa.pdf file_size: 11253627 relation: main_file success: 1 file_date_updated: 2024-07-17T09:23:24Z has_accepted_license: '1' keyword: - Quantum computing - Variational Quantum Algorithms - Optimization language: - iso: eng license: https://creativecommons.org/licenses/by/4.0/ month: '07' oa: 1 oa_version: Published Version page: '133' project: - _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: '10545' relation: part_of_dissertation status: public - id: '10067' relation: part_of_dissertation status: public - id: '17222' relation: part_of_dissertation status: public - id: '13125' relation: part_of_dissertation status: public - id: '11471' 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: Exploring the optimization landscape of variational quantum algorithms 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: '2024' ... --- OA_place: publisher _id: '17336' abstract: - lang: eng text: "This thesis deals with the study of stochastic processes and their ergodicity properties. The\r\nvariety of problems encountered calls for a set of different approaches, ranging from classical to\r\nmodern ones: a special place is held by probabilistic methods based on couplings, by functional\r\ninequalities, and by the theory of gradient flows in the space of measures.\r\n\r\nThe material is organized as follows. Chapter 1 contains the introduction to this thesis, starting\r\nwith a general presentation of some of the relevant topics. Section 1.1 is dedicated to the\r\ntheory of gradient flows in metric spaces, and introduces the first contribution of this thesis\r\n[DSMP24], which is presented in detail in Chapter 2. Section 1.2 moves to the topic of\r\ncurvature of Markov chains, concluding with a brief description of our second contribution\r\n[Ped23], which is included in Chapter 3. Section 1.3 discusses applications of stochastic\r\nprocesses to the theory of sampling, in particular the recent framework of score-based diffusion\r\nmodels, and our contribution [PMM24], which is contained in Chapter 4. Section 1.4 discusses\r\nsome related problems, concerning the regularization properties of the heat flow. It serves\r\nas a motivation for the work [BP24], which we report in Chapter 5. Finally, Section 1.5\r\ndiscusses the last contribution of this thesis, which can be found in Chapter 6. It deals with\r\nthe convergence to equilibrium of a particular stochastic model from quantitative genetics:\r\nthis is established via some functional inequalities, which we prove with probabilistic arguments\r\nbased on couplings.\r\n" alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Francesco full_name: Pedrotti, Francesco id: d3ac8ac6-dc8d-11ea-abe3-e2a9628c4c3c last_name: Pedrotti citation: ama: Pedrotti F. Functional inequalities and convergence of stochastic processes. 2024. doi:10.15479/at:ista:17336 apa: Pedrotti, F. (2024). Functional inequalities and convergence of stochastic processes. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17336 chicago: Pedrotti, Francesco. “Functional Inequalities and Convergence of Stochastic Processes.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17336. ieee: F. Pedrotti, “Functional inequalities and convergence of stochastic processes,” Institute of Science and Technology Austria, 2024. ista: Pedrotti F. 2024. Functional inequalities and convergence of stochastic processes. Institute of Science and Technology Austria. mla: Pedrotti, Francesco. Functional Inequalities and Convergence of Stochastic Processes. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17336. short: F. Pedrotti, Functional Inequalities and Convergence of Stochastic Processes, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-07-29T09:14:14Z date_published: 2024-07-31T00:00:00Z date_updated: 2026-04-07T13:00:03Z day: '31' ddc: - '500' - '510' - '515' - '519' degree_awarded: PhD department: - _id: GradSch - _id: JaMa doi: 10.15479/at:ista:17336 ec_funded: 1 file: - access_level: open_access checksum: 11650bab714ef85ad43a287060850523 content_type: application/pdf creator: fpedrott date_created: 2024-08-02T09:23:26Z date_updated: 2024-08-02T09:23:26Z file_id: '17366' file_name: thesis_final.pdf file_size: 2941599 relation: main_file success: 1 - access_level: closed checksum: c30ba5611941226cf1bfc867c25b1e80 content_type: application/x-zip-compressed creator: fpedrott date_created: 2024-08-02T09:27:15Z date_updated: 2024-08-02T09:27:15Z file_id: '17367' file_name: thesis_final_source.zip file_size: 6293375 relation: source_file file_date_updated: 2024-08-02T09:27:15Z has_accepted_license: '1' language: - iso: eng month: '07' oa: 1 oa_version: Published Version page: '183' project: - _id: 256E75B8-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '716117' name: Optimal Transport and Stochastic Dynamics - _id: fc31cba2-9c52-11eb-aca3-ff467d239cd2 grant_number: F6504 name: Taming Complexity in Partial Differential Systems publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '17351' relation: part_of_dissertation status: public - id: '17353' relation: part_of_dissertation status: public - id: '17350' relation: part_of_dissertation status: public - id: '17352' relation: part_of_dissertation status: public - id: '17143' relation: part_of_dissertation status: public status: public supervisor: - first_name: Jan full_name: Maas, Jan id: 4C5696CE-F248-11E8-B48F-1D18A9856A87 last_name: Maas orcid: 0000-0002-0845-1338 title: Functional inequalities and convergence of stochastic processes 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: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '17490' abstract: - lang: eng text: "Deep learning is essential in numerous applications nowadays, with many recent advancements made possible by training very large models. Despite their broad applicability, training neural networks is often time-intensive, and it is usually impractical to manage large models and datasets on a single machine. To address these issues, distributed deep learning training has become increasingly important. However, distributed training requires synchronization among nodes, and the mini-batch stochastic gradient descent algorithm places a significant load on network connections. A possible solution to tackle the synchronization bottleneck is to reduce a message size by lossy compression.\r\n\r\nIn this thesis, we investigate systems and algorithmic approaches to communication compression during training. From the systems perspective, we demonstrate that a common approach of expensive hardware overprovisioning can be replaced through a thorough system design. We introduce a framework that introduces efficient software support for compressed communication in machine learning applications, applicable to both multi-GPU single-node training and larger-scale multi-node training. Our framework integrates with popular ML frameworks, providing up to 3x speedups for multi-GPU nodes based on commodity hardware and order-of-magnitude improvements in the multi-node setting, with negligible impact on accuracy.\r\n\r\nAlso, we consider an application of our framework to different communication schemes, such as Fully Sharded Data Parallel. We provide strong convergence guarantees for the compression in such a setup. Empirical validation shows that our method preserves model accuracy for GPT-family models with up to 1.3 billion parameters, while completely removing the communication bottlenecks of non-compressed alternatives, providing up to 2.2x speedups end-to-end.\r\n\r\nFrom the algorithmic side, we propose a general framework that dynamically adjusts the degree of compression across a model's layers during training. This approach enhances overall compression and results in significant speedups without compromising accuracy. Our algorithm utilizes an adaptive algorithm that automatically selects the optimal compression parameters for model layers, ensuring the best compression ratio while adhering to an error constraint. Our method is effective across all existing families of compression methods. It achieves up to 2.5x faster training and up to a 5x improvement in compression compared to efficient implementations of current approaches. Additionally, LGreCo can complement existing adaptive algorithms.\r\n" acknowledged_ssus: - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Ilia full_name: Markov, Ilia id: D0CF4148-C985-11E9-8066-0BDEE5697425 last_name: Markov citation: ama: 'Markov I. Communication-efficient distributed training of deep neural networks : An algorithms and systems perspective. 2024. doi:10.15479/at:ista:17490' apa: 'Markov, I. (2024). Communication-efficient distributed training of deep neural networks : An algorithms and systems perspective. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17490' chicago: 'Markov, Ilia. “Communication-Efficient Distributed Training of Deep Neural Networks : An Algorithms and Systems Perspective.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17490.' ieee: 'I. Markov, “Communication-efficient distributed training of deep neural networks : An algorithms and systems perspective,” Institute of Science and Technology Austria, 2024.' ista: 'Markov I. 2024. Communication-efficient distributed training of deep neural networks : An algorithms and systems perspective. Institute of Science and Technology Austria.' mla: 'Markov, Ilia. Communication-Efficient Distributed Training of Deep Neural Networks : An Algorithms and Systems Perspective. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17490.' short: 'I. Markov, Communication-Efficient Distributed Training of Deep Neural Networks : An Algorithms and Systems Perspective, Institute of Science and Technology Austria, 2024.' corr_author: '1' date_created: 2024-09-04T08:51:11Z date_published: 2024-09-04T00:00:00Z date_updated: 2026-06-18T17:55:23Z day: '04' ddc: - '000' degree_awarded: PhD department: - _id: GradSch - _id: DaAl doi: 10.15479/at:ista:17490 ec_funded: 1 file: - access_level: closed checksum: 77609f4835d2730e46fa0d42d9134ed9 content_type: application/x-zip-compressed creator: imarkov date_created: 2024-09-04T08:35:35Z date_updated: 2024-09-04T08:35:35Z file_id: '17491' file_name: Thesis.zip file_size: 43327753 relation: source_file - access_level: open_access checksum: 9e68f7217570f756ceb8f70b980938cd content_type: application/pdf creator: imarkov date_created: 2024-09-04T08:36:06Z date_updated: 2024-09-04T08:36:06Z file_id: '17492' file_name: Thesis_final_version_pdfa2.pdf file_size: 2756082 relation: main_file success: 1 file_date_updated: 2024-09-04T08:36:06Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '102' project: - _id: 268A44D6-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '805223' name: Elastic Coordination for Scalable Machine Learning publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '14461' relation: part_of_dissertation status: public - id: '12780' relation: part_of_dissertation status: public - id: '17456' relation: part_of_dissertation status: public status: public supervisor: - first_name: Dan-Adrian full_name: Alistarh, Dan-Adrian id: 4A899BFC-F248-11E8-B48F-1D18A9856A87 last_name: Alistarh orcid: 0000-0003-3650-940X title: 'Communication-efficient distributed training of deep neural networks : An algorithms and systems perspective' 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: '2024' ... --- OA_place: publisher _id: '17850' abstract: - lang: eng text: "Understanding the relationship between a given phenotype and its underlying genotype or genotypes is one of the most pressing challenges of biology, as it lies at the heart of not only basic understanding of evolutionary theory, but also of practical applications in medicine and bioengineering. Understanding this relationship is complicated by the ubiquitous phenomenon of epistasis, wherein mutation effects are dependent on their genetic context. Fitness landscapes — representations of phenotype as a function of genotype — are being increasingly used as a tool to study the effects and interactions of thousands of mutations, but are experimentally limited to exploring a small fraction of a protein’s theoretical sequence space. Furthermore, not all regions of said sequence space are necessarily equally informative. Thus, gene selection for landscape surveys should be carefully considered in order to maximize the usable output of necessarily limited data.\r\n\r\nIn this work, we analyzed the fitness landscapes of orthologous green fluorescent proteins from four different species, by systematically measuring the phenotype, fluorescence, of tens of thousands of mutant genotypes from each protein. These landscapes were highly heterogeneous, with some genes being mutationally robust and displaying epistasis only rarely, and others being highly epistatic and mutationally fragile. We used this data to train machine learning models to predict fluorescence from genotype. Although the training data contained almost exclusively genotypes with less than 3% sequence divergence from the original wild-type sequences, we were able to create novel, functional genotypes with up to 20% sequence divergence. Counterintuitively however, genes with high mutational robustness and rare epistasis were more difficult to introduce large numbers of mutations into, not less. This represents the first study of large-scale fitness landscapes of a protein family, and provides insights into how to approach future landscape surveys and their applications in novel protein design." acknowledged_ssus: - _id: Bio - _id: LifeSc - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Louisa full_name: Gonzalez Somermeyer, Louisa id: 4720D23C-F248-11E8-B48F-1D18A9856A87 last_name: Gonzalez Somermeyer orcid: 0000-0001-9139-5383 citation: ama: Gonzalez Somermeyer L. Fitness landscapes of orthologous green fluorescent proteins. 2024. doi:10.15479/at:ista:17850 apa: Gonzalez Somermeyer, L. (2024). Fitness landscapes of orthologous green fluorescent proteins. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17850 chicago: Gonzalez Somermeyer, Louisa. “Fitness Landscapes of Orthologous Green Fluorescent Proteins.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17850. ieee: L. Gonzalez Somermeyer, “Fitness landscapes of orthologous green fluorescent proteins,” Institute of Science and Technology Austria, 2024. ista: Gonzalez Somermeyer L. 2024. Fitness landscapes of orthologous green fluorescent proteins. Institute of Science and Technology Austria. mla: Gonzalez Somermeyer, Louisa. Fitness Landscapes of Orthologous Green Fluorescent Proteins. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17850. short: L. Gonzalez Somermeyer, Fitness Landscapes of Orthologous Green Fluorescent Proteins, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-09-06T12:57:44Z date_published: 2024-09-06T00:00:00Z date_updated: 2026-04-07T13:25:01Z day: '06' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: FyKo doi: 10.15479/at:ista:17850 ec_funded: 1 file: - access_level: open_access checksum: d3303724e8d3c91321d71bbad4062048 content_type: application/pdf creator: lgonzale date_created: 2024-09-27T10:32:33Z date_updated: 2024-09-27T10:32:33Z file_id: '18151' file_name: louisa_thesis_draft__240904b.pdf file_size: 11219837 relation: main_file - access_level: closed checksum: 22e63f7f9014dffde2af7a47e7d1d014 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: lgonzale date_created: 2024-09-27T10:34:34Z date_updated: 2024-09-27T10:34:34Z file_id: '18152' file_name: louisa_thesis_draft__240904b.docx file_size: 43338677 relation: source_file file_date_updated: 2024-09-27T10:34:34Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '89' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program - _id: 26580278-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '771209' name: Characterizing the fitness landscape on population and global scales publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: link: - relation: software url: https://github.com/aequorea238/Orthologous_GFP_Fitness_Peaks record: - id: '11448' relation: part_of_dissertation status: public status: public supervisor: - first_name: Fyodor full_name: Kondrashov, Fyodor id: 44FDEF62-F248-11E8-B48F-1D18A9856A87 last_name: Kondrashov orcid: 0000-0001-8243-4694 title: Fitness landscapes of orthologous green fluorescent proteins 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: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '18076' abstract: - lang: eng text: "The new era of Ge has opened up new possibilities in quantum computing. The maturity of Ge\r\nspin qubits is unquestioned, while hybrid semiconductor-superconductor Ge circuits are on track\r\nto enter the game. Gate-tunable transmons (gatemons) employing semiconductor Josephson\r\njunctions have recently emerged as building blocks for such hybrid quantum circuits. In this\r\nthesis, we present a gatemon fabricated in planar Germanium. We induce superconductivity\r\nin a two-dimensional hole gas by evaporating aluminum atop a thin spacer, which separates\r\nthe superconductor from the Ge quantum well. The Josephson junction is then integrated\r\ninto an Xmon circuit and capacitively coupled to a transmission line resonator. We showcase\r\nthe qubit tunability in a broad frequency range with resonator and two-tone spectroscopy.\r\nTime-domain characterizations reveal energy relaxation and coherence times up to 75 ns. Our\r\nresults, combined with the recent advances in the spin qubit field, pave the way towards novel\r\nhybrid and protected qubits in a group IV, CMOS-compatible material." acknowledged_ssus: - _id: NanoFab - _id: M-Shop alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Oliver full_name: Sagi, Oliver id: 71616374-A8E9-11E9-A7CA-09ECE5697425 last_name: Sagi citation: ama: Sagi O. Hybrid circuits on planar Germanium. 2024. doi:10.15479/at:ista:18076 apa: Sagi, O. (2024). Hybrid circuits on planar Germanium. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18076 chicago: Sagi, Oliver. “Hybrid Circuits on Planar Germanium.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18076. ieee: O. Sagi, “Hybrid circuits on planar Germanium,” Institute of Science and Technology Austria, 2024. ista: Sagi O. 2024. Hybrid circuits on planar Germanium. Institute of Science and Technology Austria. mla: Sagi, Oliver. Hybrid Circuits on Planar Germanium. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18076. short: O. Sagi, Hybrid Circuits on Planar Germanium, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-09-16T12:58:36Z date_published: 2024-09-18T00:00:00Z date_updated: 2026-04-16T12:20:39Z day: '18' ddc: - '539' degree_awarded: PhD department: - _id: GradSch - _id: GeKa doi: 10.15479/at:ista:18076 ec_funded: 1 file: - access_level: open_access checksum: d01d0e2846c2f3ac5bb14d321554a4cd content_type: application/pdf creator: osagi date_created: 2024-09-18T14:13:01Z date_updated: 2024-09-18T14:13:01Z file_id: '18093' file_name: OliverSagi_Thesis_pdfa.pdf file_size: 86679095 relation: main_file success: 1 - access_level: local checksum: 0543f473d509ee545f4ed3a56f742f4b content_type: application/x-zip-compressed creator: osagi date_created: 2024-09-18T14:14:02Z date_updated: 2024-09-19T09:20:33Z file_id: '18094' file_name: Thesis_OliverSagi.zip file_size: 172098524 relation: source_file file_date_updated: 2024-09-19T09:20:33Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '111' project: - _id: bd8bd29e-d553-11ed-ba76-f0070d4b237a grant_number: P36507 name: Merging spin and superconducting qubits in planar Ge - _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1 grant_number: I05060 name: High impedance circuit quantum electrodynamics with hole spins - _id: 262116AA-B435-11E9-9278-68D0E5697425 name: Hybrid Semiconductor - Superconductor Quantum Devices - _id: 237E5020-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '862046' name: TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '17202' relation: part_of_dissertation status: public status: public supervisor: - first_name: Georgios full_name: Katsaros, Georgios id: 38DB5788-F248-11E8-B48F-1D18A9856A87 last_name: Katsaros orcid: 0000-0001-8342-202X title: Hybrid circuits on planar Germanium 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: '2024' ... --- OA_place: publisher _id: '18088' abstract: - lang: eng text: "Instant messaging applications like Whatsapp, Signal or Telegram have become ubiquitous in today's society.\r\nMany of them provide not only end-to-end encryption, but also security guarantees even when the key material gets compromised.\r\nThese are achieved through frequent key update performed by users.\r\nIn particular, the compromise of a group key should preserve confidentiality of previously exchanged messages (forward secrecy), and a subsequent key update will ensure security for future ones (post-compromise security).\r\nThough great protocols for one-on-one communication have been known for some time, the design of ones that scale efficiently for larger groups while achieving akin security guarantees is a hard problem.\r\nA great deal of research has been aimed at this topic, much of it under the umbrella of the Messaging Layer Security (MLS) working group at the IETF. \r\nStarted in 2018, this joint effort by academics and industry culminated in 2023 with the publication of the first standard for secure group messaging [IETF, RFC9420].\r\n\r\nAt the core of secure group messaging is a cryptographic primitive termed Continuous Group Key Agreement, or CGKA [Alwen et al. 2021], that essentially allows a changing group of users to agree on a common key with the added functionality security against compromises is achieved by users asynchronously issuing a key update. In this thesis we contribute to the understanding of CGKA across different angles.\r\nFirst, we present a new technique to effect dynamic operations in groups, i.e., add or remove members, that can be more efficient that the one employed by MLS in certain settings.\r\nConsidering the setting of users belonging to multiple overlapping groups, we then show lowerbounds on the communication cost of constructions that leverage said overlap, at the same time showing protocols that are asymptotically optimal and efficient for practical settings, respectively. Along the way, we show that the communication cost of key updates in MLS is average-cost optimal.\r\nAn important feature in CGKA protocols, particularly for big groups, is the possibility of executing several group operations concurrently. While later versions of MLS support this, they do at the cost of worsening the communication efficiency of future group operations.\r\nIn this thesis we introduce two new protocols that permit concurrency without any negative effect on efficiency. Our protocols circumvent previously existing lower bounds by satisfying a new notion of post-compromise security that only asks for security to be re-established after a certain number of key updates have taken place. While this can be slower than MLS in terms of rounds of communication, we show that it leads to more efficient overall communication. \r\nAdditionally, we introduce a new technique that allows group members to decrease the information they need to store and download, which makes one of our protocols enjoy much lower download cost than any other existing CGKA constructions. " alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Guillermo full_name: Pascual Perez, Guillermo id: 2D7ABD02-F248-11E8-B48F-1D18A9856A87 last_name: Pascual Perez orcid: 0000-0001-8630-415X citation: ama: Pascual Perez G. On the efficiency and security of secure group messaging. 2024. doi:10.15479/at:ista:18088 apa: Pascual Perez, G. (2024). On the efficiency and security of secure group messaging. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18088 chicago: Pascual Perez, Guillermo. “On the Efficiency and Security of Secure Group Messaging.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18088. ieee: G. Pascual Perez, “On the efficiency and security of secure group messaging,” Institute of Science and Technology Austria, 2024. ista: Pascual Perez G. 2024. On the efficiency and security of secure group messaging. Institute of Science and Technology Austria. mla: Pascual Perez, Guillermo. On the Efficiency and Security of Secure Group Messaging. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18088. short: G. Pascual Perez, On the Efficiency and Security of Secure Group Messaging, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-09-18T12:59:49Z date_published: 2024-09-18T00:00:00Z date_updated: 2026-04-07T13:01:26Z day: '18' ddc: - '000' degree_awarded: PhD department: - _id: KrPi - _id: GradSch doi: 10.15479/at:ista:18088 ec_funded: 1 file: - access_level: closed checksum: ce0dca715b3df48e52e2e891b6ac1bc5 content_type: application/x-zip-compressed creator: gpascual date_created: 2024-09-19T12:35:38Z date_updated: 2024-09-19T12:35:38Z file_id: '18099' file_name: thesis_bundle.zip file_size: 11917734 relation: source_file - access_level: open_access checksum: 4a2c72e90f1a0ef2a13cff800f8d1265 content_type: application/pdf creator: gpascual date_created: 2024-09-19T12:36:08Z date_updated: 2024-09-19T12:36:08Z file_id: '18100' file_name: thesis_gpasper.pdf file_size: 2729427 relation: main_file file_date_updated: 2024-09-19T12:36:08Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '239' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '10408' relation: part_of_dissertation status: public - id: '11476' relation: part_of_dissertation status: public - id: '18086' relation: part_of_dissertation status: public - id: '10049' relation: part_of_dissertation status: public status: public supervisor: - first_name: Krzysztof Z full_name: Pietrzak, Krzysztof Z id: 3E04A7AA-F248-11E8-B48F-1D18A9856A87 last_name: Pietrzak orcid: 0000-0002-9139-1654 title: On the efficiency and security of secure group messaging 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: '2024' ... --- OA_place: publisher _id: '18132' abstract: - lang: eng text: "In this thesis, we are dealing with both arithmetic and geometric problems coming from the\r\nstudy of rational points with a particular focus on function fields over finite fields:\r\n(1) Using the circle method we produce upper bounds for the number of rational points of\r\nbounded height on diagonal cubic surfaces and fourfolds over Fq(t). This is based on\r\njoint work with Leonhard Hochfilzer.\r\n(2) We study rational points on smooth complete intersections X defined by cubic and\r\nquadratic hypersurfaces over Fq(t). We refine the Farey dissection of the “unit square”\r\ndeveloped by Vishe [202] and use the circle method with a Kloosterman refinement to\r\nestablish an asymptotic formula for the number of rational points of bounded height on\r\nX when dim(X) ≥ 23. Under the same hypotheses, we also verify weak approximation.\r\n(3) In joint work with Hochfilzer, we obtain upper bounds for the number of rational points of\r\nbounded height on del Pezzo surfaces of low degree over any global field. Our approach\r\nis to take hyperplane sections, which reduces the problem to uniform estimates for the\r\nnumber of rational points on curves.\r\n(4) We develop a version of the circle method capable of counting Fq-points on jet schemes\r\nof moduli spaces of rational curves on hypersurfaces. Combining this with a spreading\r\nout argument and a result of Mustaţă [150], this allows us to show that these moduli\r\nspaces only have canonical singularities under suitable assumptions on the degree and the\r\ndimension.\r\nIn addition, we give an overview of guiding questions and conjectures in the field of rational\r\npoints and explain the basic mechanism underlying the circle method.\r\n" alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Jakob full_name: Glas, Jakob id: d6423cba-dc74-11ea-a0a7-ee61689ff5fb last_name: Glas citation: ama: Glas J. Counting rational points over function fields. 2024. doi:10.15479/at:ista:18132 apa: Glas, J. (2024). Counting rational points over function fields. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18132 chicago: Glas, Jakob. “Counting Rational Points over Function Fields.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18132. ieee: J. Glas, “Counting rational points over function fields,” Institute of Science and Technology Austria, 2024. ista: Glas J. 2024. Counting rational points over function fields. Institute of Science and Technology Austria. mla: Glas, Jakob. Counting Rational Points over Function Fields. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18132. short: J. Glas, Counting Rational Points over Function Fields, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-09-23T18:58:08Z date_published: 2024-09-23T00:00:00Z date_updated: 2026-04-07T12:53:54Z day: '23' ddc: - '512' degree_awarded: PhD department: - _id: GradSch - _id: TiBr doi: 10.15479/at:ista:18132 file: - access_level: closed checksum: 2f8cf5cefdab108b1979caa8146cae9a content_type: application/x-zip-compressed creator: jglas date_created: 2024-09-23T18:49:22Z date_updated: 2024-09-23T18:49:22Z file_id: '18133' file_name: PhDthesis (3).zip file_size: 5382106 relation: source_file - access_level: open_access checksum: 08bb6f14c42b47ff25882a2ce3ea0d8a content_type: application/pdf creator: jglas date_created: 2024-09-25T14:08:57Z date_updated: 2024-09-25T14:08:57Z file_id: '18140' file_name: example-phd.pdf file_size: 2380127 relation: main_file success: 1 file_date_updated: 2024-09-25T14:08:57Z has_accepted_license: '1' language: - iso: eng license: https://creativecommons.org/licenses/by-nc/4.0/ month: '09' oa: 1 oa_version: Published Version page: '195' project: - _id: bd8a4fdc-d553-11ed-ba76-80a0167441a3 grant_number: P36278 name: Rational curves via function field analytic number theory publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '18293' relation: part_of_dissertation status: public - id: '18294' relation: part_of_dissertation status: public - id: '18295' relation: part_of_dissertation status: public - id: '18173' 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: Counting rational points over function fields tmp: image: /images/cc_by_nc.png legal_code_url: https://creativecommons.org/licenses/by-nc/4.0/legalcode name: Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) short: CC BY-NC (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '18135' abstract: - lang: eng text: "This thesis consists of two separate parts. In the first part we consider a dilute Fermi gas interacting through a repulsive interaction in dimensions $d=1,2,3$. Our focus is mostly on the physically most relevant dimension $d=3$ \r\nand the setting of a spin-polarized (equivalently spinless) gas, where the Pauli exclusion principle plays a key role. We show that, at zero temperature, the ground state energy density of the interacting spin-polarized gas differs (to leading order) from that of the free (i.e. non-interacting) gas by a term of order $a_p^d\\rho^{2+2/d}$ \ with $a_p$ the $p$-wave scattering length of the repulsive interaction and $\\rho$ the density. Further, we extend this to positive temperature and show that the pressure of an interacting spin-polarized gas differs from that of the free gas by a now temperature dependent term, again of order $a_p^d\\rho^{2+2/d}$. Lastly, we consider the setting of a spin-$\\frac{1}{2}$ Fermi gas in $d=3$ dimensions and show that here, as an upper bound, the ground state energy density differs from that of the free system by a term of order $a_s \\rho^2$ with an error smaller than $a_s \\rho^2 (a_s\\rho^{1/3})^{1-\\eps}$ for any $\\eps > 0$, where $a_s$ is the $s$-wave scattering length of the repulsive interaction. \r\n\r\nThese asymptotic formulas complement the similar formulas in the literature for the dilute Bose and spin-$\\frac{1}{2}$ Fermi gas, where the ground state energies or pressures differ from that of the corresponding free systems by a term of order $a_s \\rho^2$ in dimension $d=3$. In the spin-polarized setting, the corrections, of order $a_p^3\\rho^{8/3}$ in dimension $d=3$, are thus much smaller and requires a more delicate analysis.\r\n\r\nIn the second part of the thesis we consider the Bardeen--Cooper--Schrieffer (BCS) theory of superconductivity and in particular its associated critical temperature and energy gap. We prove that the ratio of the zero-temperature energy gap and critical temperature $\\Xi(T=0)/T_c$ approaches a universal constant $\\pi e^{-\\gamma}\\approx 1.76$ in both the limit of high density in dimension $d=3$ and in the limit of weak coupling in dimensions $d=1,2$. This complements the proofs in the literature of this universal behaviour in the limit of weak coupling or low density in dimension $d=3$. Secondly, we prove that the ratio of the energy gap at positive temperature and critical temperature $\\Xi(T)/T_c$ approaches a universal function of the relative temperature $T/T_c$ in the limit of weak coupling in dimensions $d=1,2,3$." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Asbjørn Bækgaard full_name: Lauritsen, Asbjørn Bækgaard id: e1a2682f-dc8d-11ea-abe3-81da9ac728f1 last_name: Lauritsen orcid: 0000-0003-4476-2288 citation: ama: Lauritsen AB. Energies of dilute Fermi gases and universalities in BCS theory. 2024. doi:10.15479/at:ista:18135 apa: Lauritsen, A. B. (2024). Energies of dilute Fermi gases and universalities in BCS theory. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18135 chicago: Lauritsen, Asbjørn Bækgaard. “Energies of Dilute Fermi Gases and Universalities in BCS Theory.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18135. ieee: A. B. Lauritsen, “Energies of dilute Fermi gases and universalities in BCS theory,” Institute of Science and Technology Austria, 2024. ista: Lauritsen AB. 2024. Energies of dilute Fermi gases and universalities in BCS theory. Institute of Science and Technology Austria. mla: Lauritsen, Asbjørn Bækgaard. Energies of Dilute Fermi Gases and Universalities in BCS Theory. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18135. short: A.B. Lauritsen, Energies of Dilute Fermi Gases and Universalities in BCS Theory, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-09-24T10:56:25Z date_published: 2024-09-23T00:00:00Z date_updated: 2026-04-16T08:17:55Z day: '23' ddc: - '515' - '539' degree_awarded: PhD department: - _id: GradSch - _id: RoSe doi: 10.15479/at:ista:18135 ec_funded: 1 file: - access_level: open_access checksum: c7bc3b31e430d57c65393051ca439575 content_type: application/pdf creator: alaurits date_created: 2024-09-26T13:11:24Z date_updated: 2024-09-26T13:11:24Z file_id: '18147' file_name: Lauritsen-thesis-final.pdf file_size: 3648831 relation: main_file success: 1 - access_level: closed checksum: 39f6b1b7f83e25a3bf9f933f1ea0bc06 content_type: application/x-zip-compressed creator: alaurits date_created: 2024-09-26T13:12:55Z date_updated: 2024-09-26T13:12:55Z file_id: '18148' file_name: Lauritsen-thesis-source.zip file_size: 1625888 relation: source_file file_date_updated: 2024-09-26T13:12:55Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '353' project: - _id: bda63fe5-d553-11ed-ba76-a16e3d2f256b grant_number: I06427 name: Mathematical Challenges in BCS Theory of Superconductivity - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication_identifier: isbn: - 978-3-99078-042-8 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11732' relation: part_of_dissertation status: public - id: '14542' relation: part_of_dissertation status: public - id: '18107' relation: part_of_dissertation status: public - id: '17240' relation: part_of_dissertation status: public - id: '14931' relation: part_of_dissertation status: public status: public supervisor: - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 title: Energies of dilute Fermi gases and universalities in BCS theory 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: '2024' ... --- OA_place: publisher OA_type: free access _id: '18443' abstract: - lang: eng text: "In [KW06] Kapustin and Witten conjectured that there is a mirror symmetry relation between\r\nthe hyperkähler structures on certain Higgs bundle moduli spaces. As a consequence, they\r\nconjecture an equivalence between categories of BBB and BAA-branes. At the classical\r\nlevel, this mirror symmetry is given by T-duality between semi-flat hyperkähler structures on\r\nalgebraic integrable systems.\r\nIn this thesis, we investigate the T-duality relation between hyperkähler structures and the\r\ncorresponding branes on affine torus bundles. We use the techniques of generalized geometry\r\nto show that semi-flat hyperkähler structures are T-dual on algebraic integrable systems.\r\nWe also describe T-duality for generalized branes. Motivated by Fourier-Mukai transform\r\nwe upgrade the T-duality between generalized branes to T-duality of submanifolds endowed\r\nwith U(1)-bundles and connections. This T-duality in the appropriate context specializes to\r\nT-duality between BBB and BAA-branes.\r\n" alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Maria A full_name: Sisak, Maria A id: 44A03D04-AEA4-11E9-B225-EA2DE6697425 last_name: Sisak citation: ama: Sisak MA. T-dual branes on hyperkähler manifolds. 2024. doi:10.15479/at:ista:18443 apa: Sisak, M. A. (2024). T-dual branes on hyperkähler manifolds. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18443 chicago: Sisak, Maria A. “T-Dual Branes on Hyperkähler Manifolds.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18443. ieee: M. A. Sisak, “T-dual branes on hyperkähler manifolds,” Institute of Science and Technology Austria, 2024. ista: Sisak MA. 2024. T-dual branes on hyperkähler manifolds. Institute of Science and Technology Austria. mla: Sisak, Maria A. T-Dual Branes on Hyperkähler Manifolds. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18443. short: M.A. Sisak, T-Dual Branes on Hyperkähler Manifolds, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-10-19T12:00:37Z date_published: 2024-10-24T00:00:00Z date_updated: 2026-04-07T12:42:44Z day: '24' ddc: - '516' degree_awarded: PhD department: - _id: GradSch - _id: TaHa doi: 10.15479/at:ista:18443 file: - access_level: open_access checksum: 8c4893e726aaa4b3efb82758da9b6851 content_type: application/pdf creator: msisak date_created: 2024-10-23T14:42:45Z date_updated: 2024-10-23T14:42:45Z file_id: '18467' file_name: MASisak_dissertation.pdf file_size: 1672547 relation: main_file success: 1 - access_level: closed checksum: 1831b072e861a1e5481024ca9d02b036 content_type: application/x-zip-compressed creator: msisak date_created: 2024-10-23T14:43:56Z date_updated: 2024-10-24T08:09:13Z file_id: '18468' file_name: MASisak_source.zip file_size: 617913 relation: source_file file_date_updated: 2024-10-24T08:09:13Z has_accepted_license: '1' keyword: - hyperkaehler geometry - branes - mirror symmetry - T-duality language: - iso: eng month: '10' oa: 1 oa_version: Published Version page: '178' project: - _id: 6286e8c4-2b32-11ec-9570-f5297902f67f grant_number: '26069' name: Branes on hyperkähler manifolds publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Tamás full_name: Hausel, Tamás id: 4A0666D8-F248-11E8-B48F-1D18A9856A87 last_name: Hausel orcid: 0000-0002-9582-2634 title: T-dual branes on hyperkähler manifolds 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: '2024' ... --- OA_place: publisher _id: '17485' abstract: - lang: eng text: "Large language models (LLMs) have made tremendous progress in the past few years, from being able to generate coherent text to matching or surpassing humans in a wide variety of creative, knowledge or reasoning tasks. Much of this can be attributed to massively increased scale, both in the size of the model as well as the amount of training data, from 100s of millions to 100s of billions, or even trillions. This trend is expected to continue, which, although exciting, also raises major practical concerns. Already today's 100+ billion parameter LLMs require top-of-the-line hardware just to run. Hence, it is clear that sustaining these developments will require significant efficiency advances.\r\n\r\nHistorically, one of the most practical ways of improving model efficiency has been compression, especially in the form of sparsity or quantization. While this has been studied extensively in the past, existing accurate methods are all designed for models around 100 million parameters; scaling them up to ones literally 1000x larger is highly challenging. In this thesis, we introduce a new unified sparsification and quantization approach OBC, which through additional algorithmic enhancements leads to GPTQ and SparseGPT, the first techniques fast and accurate enough to compress 100+ billion parameter models to 4- or even 3-bit precision and 50% weight-sparsity, respectively. Additionally, we show how weight-only quantizion does not just bring space savings but also up to 4.5x faster generation speed, via custom GPU kernels.\r\n\r\nIn fact, we show for the first time that it is possible to develop an FP16 times INT4 mixed-precision matrix multiplication kernel, called Marlin, which comes close to simultaneously maximizing both memory and compute utilization, making weight-only quantization highly practical even for multi-user serving. Further, we demonstrate that GPTQ can be scaled to widely overparametrized trillion-parameter models, where extreme sub-1-bit compression rates can be achieved without any inference slow-down, by co-designing a bespoke entropy coding scheme together with an efficient kernel.\r\n\r\nFinally, we also study compression from the perspective of someone with access to massive amounts of compute resources for training large models completely from scratch. Here the key questions evolve around the joint scaling behavior between compression, model size, and amount of training data used. Based on extensive experimental results for both vision and text models, we introduce the first scaling law which accurately captures the relationship between weight-sparsity, number of non-zero weights and data. This further allows us to characterize the optimal sparsity, which we find to increase the longer a fixed cost model is being trained.\r\n\r\nOverall, this thesis presents contributions to three different angles of large model efficiency: affordable but accurate algorithms, highly efficient systems implementations, and fundamental scaling laws for compressed training." acknowledged_ssus: - _id: ScienComp alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Elias full_name: Frantar, Elias id: 09a8f98d-ec99-11ea-ae11-c063a7b7fe5f last_name: Frantar citation: ama: 'Frantar E. Compressing large neural networks : Algorithms, systems and scaling laws. 2024. doi:10.15479/at:ista:17485' apa: 'Frantar, E. (2024). Compressing large neural networks : Algorithms, systems and scaling laws. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17485' chicago: 'Frantar, Elias. “Compressing Large Neural Networks : Algorithms, Systems and Scaling Laws.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17485.' ieee: 'E. Frantar, “Compressing large neural networks : Algorithms, systems and scaling laws,” Institute of Science and Technology Austria, 2024.' ista: 'Frantar E. 2024. Compressing large neural networks : Algorithms, systems and scaling laws. Institute of Science and Technology Austria.' mla: 'Frantar, Elias. Compressing Large Neural Networks : Algorithms, Systems and Scaling Laws. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17485.' short: 'E. Frantar, Compressing Large Neural Networks : Algorithms, Systems and Scaling Laws, Institute of Science and Technology Austria, 2024.' corr_author: '1' date_created: 2024-09-02T11:01:48Z date_published: 2024-09-05T00:00:00Z date_updated: 2026-07-07T13:22:38Z day: '05' ddc: - '000' degree_awarded: PhD department: - _id: GradSch - _id: DaAl doi: 10.15479/at:ista:17485 ec_funded: 1 file: - access_level: closed checksum: 5d785645805a78c5b4ce7cc3df557b09 content_type: application/zip creator: efrantar date_created: 2024-09-05T12:04:11Z date_updated: 2024-09-05T12:04:11Z file_id: '17570' file_name: thesis-final.zip file_size: 1615167 relation: source_file - access_level: open_access checksum: a9dd1c2d23734986924eb44ebb55fd8f content_type: application/pdf creator: efrantar date_created: 2024-09-06T16:24:59Z date_updated: 2024-09-06T16:24:59Z file_id: '17880' file_name: frantar_thesis_final.pdf file_size: 2376611 relation: main_file success: 1 file_date_updated: 2024-09-06T16:24:59Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '129' project: - _id: 268A44D6-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '805223' name: Elastic Coordination for Scalable Machine Learning publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '17378' relation: part_of_dissertation status: public - id: '17087' relation: part_of_dissertation status: public - id: '14458' relation: part_of_dissertation status: public - id: '18062' relation: part_of_dissertation status: public - id: '18061' relation: part_of_dissertation status: public status: public supervisor: - first_name: Dan-Adrian full_name: Alistarh, Dan-Adrian id: 4A899BFC-F248-11E8-B48F-1D18A9856A87 last_name: Alistarh orcid: 0000-0003-3650-940X title: 'Compressing large neural networks : Algorithms, systems and scaling laws' type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ... --- OA_place: publisher _id: '18667' abstract: - lang: eng text: "Many chemical and physical properties of materials are determined by the material’s shape,\r\nfor example the size of its pores and the width of its tunnels. This makes materials science\r\na prime application area for geometrical and topological methods. Nevertheless many\r\nmethods in topological data analysis have not been satisfyingly extended to the needs of\r\nmaterials science. This thesis provides new methods and new mathematical theorems\r\ntargeted at those specific needs by answering four different research questions. While the\r\nmotivation for each of the research questions arises from materials science, the methods\r\nare versatile and can be applied in different areas as well. \r\n\r\nThe first research question is concerned with image data, for example a three-dimensional\r\ncomputed tomography (CT) scan of a material, like sand or stone. There are two commonly\r\nused topologies for digital images and depending on the application either of them might be\r\nrequired. However, software for computing the topological data analysis method persistence\r\nhomology, usually supports only one of the two topologies. We answer the question how to\r\ncompute persistent homology of an image with respect to one of the two topologies using\r\nsoftware that is intended for the other topology. \r\n\r\nThe second research question is concerned with image data as well, and asks how much\r\nof the topological information of an image is lost when the resolution is coarsened. As\r\ncomputer tomography scanners are more expensive the higher the resolution, it is an\r\nimportant question in materials science to know which resolution is enough to get satisfying\r\npersistent homology. We give theoretical bounds on the information loss based on different\r\ngeometrical properties of the object to be scanned. In addition, we conduct experiments on\r\nsand and stone CT image data. \r\n\r\nThe third research question is motivated by comparing crystalline materials efficiently. As\r\nthe atoms within a crystal repeat periodically, crystalline materials are either modeled by\r\nunmanageable infinite periodic point sets, or by one of their fundamental domains, which is\r\nunstable under perturbation. Therefore a fingerprint of crystalline materials is needed, with\r\nappropriate properties such that comparing the crystals can be eased by comparing the\r\nfingerprints instead. We define the density fingerprint and prove the necessary properties. \r\n\r\nThe fourth research question is motivated by studying the hole-structure or connectedness,\r\ni.e. persistent homology or merge trees, of crystalline materials. A common way to deal\r\nwith periodicity is to take a fundamental domain and identify opposite boundaries to form a\r\ntorus. However, computing persistent homology or merge trees on that torus loses some\r\nof the information materials scientists are interested in and is additionally not stable under\r\ncertain noise. We therefore decorate the merge tree stemming from the torus with additional\r\ninformation describing the density and growth rate of the periodic copies of a component\r\nwithin a growing spherical window. We prove all desired properties, like stability and efficient\r\ncomputability." acknowledgement: "I was supported by the European Research Council (ERC) Horizon 2020 project\r\n“Alpha Shape Theory Extended” No. 788183 and by the Pöttinger Scholarship. In addition,\r\nI am very thankful for having been able to attend the second Workshop for Women in\r\nComputational Topology in July 2019, funded by the Mathematical Sciences Institute at\r\nANU, the US National Science Foundation through the award CCF-1841455, the Australian\r\nMathematical Sciences Institute and the Association for Women in Mathematics. Two of the\r\nprojects presented in this thesis started there. One of them reached completion thanks to\r\nfunding from the MSRI Summer Research in Mathematics program awarded to me and my\r\ncollaborators in 2020." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Teresa full_name: Heiss, Teresa id: 4879BB4E-F248-11E8-B48F-1D18A9856A87 last_name: Heiss orcid: 0000-0002-1780-2689 citation: ama: Heiss T. New methods for applying topological data analysis to materials science. 2024. doi:10.15479/at:ista:18667 apa: Heiss, T. (2024). New methods for applying topological data analysis to materials science. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18667 chicago: Heiss, Teresa. “New Methods for Applying Topological Data Analysis to Materials Science.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18667. ieee: T. Heiss, “New methods for applying topological data analysis to materials science,” Institute of Science and Technology Austria, 2024. ista: Heiss T. 2024. New methods for applying topological data analysis to materials science. Institute of Science and Technology Austria. mla: Heiss, Teresa. New Methods for Applying Topological Data Analysis to Materials Science. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18667. short: T. Heiss, New Methods for Applying Topological Data Analysis to Materials Science, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-12-17T16:17:55Z date_published: 2024-12-17T00:00:00Z date_updated: 2026-07-07T13:43:27Z day: '17' ddc: - '514' - '516' - '004' degree_awarded: PhD department: - _id: GradSch - _id: HeEd doi: 10.15479/at:ista:18667 ec_funded: 1 file: - access_level: open_access checksum: 247bb057aed2fba1cd4711917aaa2d77 content_type: application/pdf creator: theiss date_created: 2024-12-19T10:24:46Z date_updated: 2024-12-19T10:24:46Z file_id: '18686' file_name: Teresa_Heiss_PhD_Thesis_final.pdf file_size: 7752253 relation: main_file success: 1 - access_level: closed checksum: 9648b45c07a008ee11a07f99856a139d content_type: application/zip creator: theiss date_created: 2024-12-19T10:24:50Z date_updated: 2024-12-19T10:24:50Z file_id: '18687' file_name: PhD_Thesis.zip file_size: 17197731 relation: source_file file_date_updated: 2024-12-19T10:24:50Z has_accepted_license: '1' keyword: - persistent homology - topological data analysis - periodic - crystalline materials - images - fingerprint language: - iso: eng month: '12' oa: 1 oa_version: Published Version page: '111' project: - _id: 266A2E9E-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '788183' name: Alpha Shape Theory Extended publication_identifier: isbn: - 978-3-99078-052-7 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '10828' relation: part_of_dissertation status: public - id: '11440' relation: part_of_dissertation status: public - id: '18673' relation: part_of_dissertation status: public - id: '9345' relation: part_of_dissertation status: public 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: New methods for applying topological data analysis to materials science 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: '2024' ... --- OA_place: publisher _id: '17225' abstract: - lang: eng text: "This thesis describes the development of an atom interferometer designed to exploit the\r\nadvantages of utilizing quantum entanglement for enhanced precision measurements beyond\r\nthe standard quantum limit. While the project remains ongoing, significant progress has been\r\nmade.\r\nA key contribution of this work is the development of Quantrol, an experimental control\r\nsystem leveraging the ARTIQ framework. This software enables precise timing and control\r\nwithout requiring prior knowledge of ARTIQ’s implementation details or coding experience.\r\nThe interface offers user friendly visual comprehension of the experimental sequence and\r\nextended capabilities, allowing researchers to scan variables with a simple click of a mouse.\r\nThe main proposed project is to implement atom interferometric sequence with squeezed input\r\nstates inside of a dipole trap generated by a high finesse cavity. The presence of the dipole\r\ntrap allows one dimensional atomic cloud split while maintaining relatively strong confinement\r\nin other directions.\r\nWe are currently able to trap and cool 87Rb atoms to few micro kelvin temperatures, load\r\nthem into the dipole trap and state prepare them to be used for squeezing and interferometric\r\nsequence." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Vyacheslav full_name: Li, Vyacheslav id: 3A4FAA92-F248-11E8-B48F-1D18A9856A87 last_name: Li citation: ama: Li V. Towards a quantum entanglement enhanced atom interferomter. 2024. doi:10.15479/at:ista:17225 apa: Li, V. (2024). Towards a quantum entanglement enhanced atom interferomter. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17225 chicago: Li, Vyacheslav. “Towards a Quantum Entanglement Enhanced Atom Interferomter.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17225. ieee: V. Li, “Towards a quantum entanglement enhanced atom interferomter,” Institute of Science and Technology Austria, 2024. ista: Li V. 2024. Towards a quantum entanglement enhanced atom interferomter. Institute of Science and Technology Austria. mla: Li, Vyacheslav. Towards a Quantum Entanglement Enhanced Atom Interferomter. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17225. short: V. Li, Towards a Quantum Entanglement Enhanced Atom Interferomter, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-07-11T09:46:48Z date_published: 2024-07-11T00:00:00Z date_updated: 2026-07-08T08:50:57Z day: '11' ddc: - '530' degree_awarded: PhD department: - _id: GradSch - _id: OnHo doi: 10.15479/at:ista:17225 file: - access_level: open_access checksum: 15b2dbe8d2c9ed7ca5dd413827928077 content_type: application/pdf creator: vli date_created: 2024-07-11T10:26:22Z date_updated: 2024-07-11T10:26:22Z file_id: '17228' file_name: PhD_Thesis_Vyacheslav_Li_no_signatures_PDFA.pdf file_size: 6729761 relation: main_file success: 1 - access_level: closed checksum: 16e904a11d8d0ebb167cb654ddfc7fe5 content_type: application/x-zip-compressed creator: vli date_created: 2024-07-11T10:26:22Z date_updated: 2024-07-11T10:26:22Z file_id: '17229' file_name: PhD Thesis Vyacheslav Li.zip file_size: 9542859 relation: source_file file_date_updated: 2024-07-11T10:26:22Z has_accepted_license: '1' language: - iso: eng month: '07' oa: 1 oa_version: Published Version page: '79' project: - _id: bdb2a702-d553-11ed-ba76-f12e3e5a3bc6 grant_number: '101087907' name: 'A quantum hybrid of atoms and milligram-scale pendulums: towards gravitational quantum mechanics' publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '11438' relation: part_of_dissertation status: public status: public supervisor: - first_name: Onur full_name: Hosten, Onur id: 4C02D85E-F248-11E8-B48F-1D18A9856A87 last_name: Hosten orcid: 0000-0002-2031-204X title: Towards a quantum entanglement enhanced atom interferomter 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: '2024' ... --- OA_place: publisher _id: '17119' abstract: - lang: eng text: "Genomes are shaped by natural selection at the level of the organism, as genomic variants that\r\nhave a beneficial effect on the viability or fecundity of their carriers are on average expected\r\nto be passed on to more offspring than less beneficial alleles. However, selection also favors\r\ngenomic variants that drive their own transmission to the next generation above the mendelian\r\nexpectation of 50 percent in heterozygotes, even if these self-promoting variants are less\r\nbeneficial to the organism than other variants at the same locus. Such variants, called meiotic\r\ndrivers, are found in diverse taxa, and often impose fitness costs on their host organisms. As\r\nmeiotic drivers often require multiple genes and sequences for transmission ratio distortion,\r\nthey are often found in regions of low recombination, such as inversions, which prevent their\r\nrecombination with the non-driving homologous regions. Reduced recombination rates are\r\nexpected to lead to the accumulation of deleterious mutations, which may affect hundreds\r\nof genes trapped in the inversions of meiotic drivers. Although the observed fitness costs of\r\nself-promoting haplotypes are thought to possibly reflect sequence degeneration, no study has\r\nsystematically investigated the level of degeneration on a meiotic driver. Further, the low\r\nrates of recombination between driving and non-driving haplotypes have limited the power of\r\ntraditional genetic studies in uncovering the gene content of meiotic drivers, and made the\r\nthe identification of the genes causing transmission ratio distortion difficult.\r\nAfter an introduction to meiotic drivers in Chapter 1, this thesis presents three studies that\r\nmake use of next generation sequencing data to characterize the sequence and expression\r\nevolution of genes on the t-haplotype, a large and ancient meiotic driver in house mice that is\r\ntransmitted to up to 100% of the offspring in males heterozygous for it. Chapter 2 presents\r\na comprehensive assessment of the t-haplotype’s sequence evolution, which shows signs of\r\nsequence degeneration counteracted by occasional recombination with the non-driving homolog\r\nover large parts of the meiotic driver, proposing an explanation for its long-term survival.\r\nChapter 3 investigates the sequence and expression evolution of genes on the t-haplotype,\r\nand finds widespread expression and copy number changes and signs of less efficient purifying\r\nselection compared to the genes on the non-driving homolog. Further, this chapter finds\r\ncandidates for involvment in drive: two positively selected genes on the t-haplotype, and\r\nthe discovery of a t-specific gene duplicate, which was gained from another chromosome,\r\nand which acquired novel sequence and testis-specific expression on the t-haplotype. Finally,\r\nChapter 4 provides unprecedented insights into the gene expression landscape in testes of\r\nt-carrier mice, using single nucleus sequencing. Cell-resolved RNA-sequencing allows the\r\ncomparison of expression in spermatids carrying or not carrying the t-haplotype as well as the\r\ntiming of t-haplotype-induced expression changes along spermatogenesis. This study shows\r\nthe timing of previously found drive-associated genes, and uncovers novel candidate genes and\r\nbiological processes that may underlie the complex biology of transmission ratio distortion of\r\nthe t-haplotype. Chapter 5 synthesizes the findings of the three studies, and discusses them in\r\nthe context of the current state of meiotic drive research." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Réka K full_name: Kelemen, Réka K id: 48D3F8DE-F248-11E8-B48F-1D18A9856A87 last_name: Kelemen orcid: 0000-0002-8489-9281 citation: ama: Kelemen RK. Characterizing the sequence and expression evolution of the t-haplotype, a model meiotic driver. 2024. doi:10.15479/at:ista:17119 apa: Kelemen, R. K. (2024). Characterizing the sequence and expression evolution of the t-haplotype, a model meiotic driver. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:17119 chicago: Kelemen, Réka K. “Characterizing the Sequence and Expression Evolution of the T-Haplotype, a Model Meiotic Driver.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:17119. ieee: R. K. Kelemen, “Characterizing the sequence and expression evolution of the t-haplotype, a model meiotic driver,” Institute of Science and Technology Austria, 2024. ista: Kelemen RK. 2024. Characterizing the sequence and expression evolution of the t-haplotype, a model meiotic driver. Institute of Science and Technology Austria. mla: Kelemen, Réka K. Characterizing the Sequence and Expression Evolution of the T-Haplotype, a Model Meiotic Driver. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:17119. short: R.K. Kelemen, Characterizing the Sequence and Expression Evolution of the T-Haplotype, a Model Meiotic Driver, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-06-07T16:14:13Z date_published: 2024-06-20T00:00:00Z date_updated: 2026-04-07T13:21:37Z day: '20' ddc: - '576' degree_awarded: PhD department: - _id: GradSch - _id: BeVi doi: 10.15479/at:ista:17119 ec_funded: 1 file: - access_level: closed checksum: fab59146e3b3dc2e5d214576984a2a63 content_type: application/zip creator: rkelemen date_created: 2024-06-07T16:09:17Z date_updated: 2025-01-10T23:30:10Z embargo_to: open_access file_id: '17121' file_name: thesis.zip file_size: 180557931 relation: source_file - access_level: open_access checksum: 91cc4c25a792239e8a7688e8aec7c62a content_type: application/pdf creator: rkelemen date_created: 2024-07-10T08:00:20Z date_updated: 2025-01-10T23:30:10Z embargo: 2025-01-10 file_id: '17213' file_name: thesis_to_archive.pdf file_size: 19405484 relation: main_file file_date_updated: 2025-01-10T23:30:10Z has_accepted_license: '1' keyword: - meiotic driver - neofunctionalization - single nucleus sequencing language: - iso: eng month: '06' oa: 1 oa_version: Published Version page: '105' project: - _id: 250BDE62-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '715257' name: Prevalence and Influence of Sexual Antagonism on Genome Evolution - _id: 34ae1506-11ca-11ed-8bc3-c14f4c474396 grant_number: F8810 name: The highjacking of meiosis for asexual reproduction publication_identifier: isbn: - 978-3-99078-039-8 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '542' relation: part_of_dissertation status: public - id: '10767' relation: part_of_dissertation status: public status: public supervisor: - first_name: Beatriz full_name: Vicoso, Beatriz id: 49E1C5C6-F248-11E8-B48F-1D18A9856A87 last_name: Vicoso orcid: 0000-0002-4579-8306 title: Characterizing the sequence and expression evolution of the t-haplotype, a model meiotic driver 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: '2024' ... --- OA_place: publisher _id: '18477' abstract: - lang: eng text: "ADAR1 is broadly expressed across various tissues and is vital in regulating pathways\r\nassociated with innate immune responses. ADAR1 marks double-stranded RNA as \"self\"\r\nthrough its A-to-I editing activity, effectively repressing autoimmunity and maintaining\r\nimmune tolerance. This editing process has been detected at millions of sites across the\r\nhuman genome. However, the mechanism underlying ADAR1's substrate selectivity\r\nproperties remains largely unclear, with much of the current knowledge derived from\r\ncomparisons to its more extensively studied homolog, ADAR2. By studying ADAR1 in complex\r\nwith its RNA substrates and applying a combination of biochemical techniques and structural\r\nstudies using CryoEM, we aim to gain a more comprehensive understanding of the substrate\r\nselectivity characteristics of ADAR1.\r\nIn this thesis, the purification protocol for ADAR1 was successfully optimized, resulting in the\r\nfirst report in the literature to achieve high protein purity and activity. This advancement\r\nenabled the investigation of complex formation between ADAR1 and various RNA substrates,\r\nleading to the identification of optimal conditions for preparing the cryoEM sample. However,\r\ndespite comprehensive optimization of the cryo-EM conditions, the resulting data lacked the\r\ndesired quality, highlighting the need for similar rigorous optimization of the RNA substrates\r\nto facilitate structural studies of the ADAR1-RNA complex. The study was complemented by\r\nAlphaFold predictions, which provided some insights into this mechanism.\r\nMoreover, during this project I established a collaboration with a research group focused on\r\nstudying ADAR homologs. Notably ADAR homologs were identified in bivalve species, and it\r\nwas further demonstrated that ADAR and its A-to-I editing activity are upregulated in Pacific\r\noysters during infections with Ostreid herpesvirus-1—a highly infectious virus that leads to\r\nsignificant losses in oyster populations globally. I successfully purified oyster ADAR and\r\nprepared in vitro edited RNA for nanopore sequencing—a direct sequencing technology\r\ncapable of detecting modified nucleotides without the need for reverse transcription. The\r\ncollaborators initiated optimization of this nanopore-based approach. However, current\r\ntechnological limitations still constrain the reliable detection of modified nucleotides.\r\nThe project also examined the impact of RNA editing on RNA binding and filament formation\r\nby MDA5, a key cytosolic dsRNA sensor that triggers an interferon response. A primary target\r\nof ADAR1's editing activity is RNA derived from repetitive elements present in the genome,\r\nparticularly Alu elements forming double-stranded RNA. When unedited, these RNA\r\nsequences are recognized by MDA5. However, the mechanisms by which MDA5 interacts with\r\nAlu RNAs, as well as the role of A-to-I editing in influencing this binding, are still not well\r\nunderstood.\r\nThe interaction between MDA5 and Alu elements, was successfully established. This was\r\nachieved through the testing of different RNA variants and the evaluation of filament\r\nformation using binding techniques and electron microscopy imaging. This groundwork has\r\nset the conditions for further evaluation using CryoEM. Furthermore, the effects of A-to-I\r\nediting on the binding properties of MDA5 with Alu RNA were investigated. Given the recent\r\nresearch that has provided new insights into MDA5's interaction with dsRNA, it is essential to\r\nrevise the experimental setup to integrate these findings before moving forward with the\r\nCryoEM sample analysis." acknowledged_ssus: - _id: EM-Fac - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Beata M full_name: Kaczmarek, Beata M id: 36FA4AFA-F248-11E8-B48F-1D18A9856A87 last_name: Kaczmarek citation: ama: Kaczmarek BM. Biochemical and structural insights into ADAR1 RNA editing. 2024. doi:10.15479/at:ista:18477 apa: Kaczmarek, B. M. (2024). Biochemical and structural insights into ADAR1 RNA editing. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:18477 chicago: Kaczmarek, Beata M. “Biochemical and Structural Insights into ADAR1 RNA Editing.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:18477. ieee: B. M. Kaczmarek, “Biochemical and structural insights into ADAR1 RNA editing,” Institute of Science and Technology Austria, 2024. ista: Kaczmarek BM. 2024. Biochemical and structural insights into ADAR1 RNA editing. Institute of Science and Technology Austria. mla: Kaczmarek, Beata M. Biochemical and Structural Insights into ADAR1 RNA Editing. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:18477. short: B.M. Kaczmarek, Biochemical and Structural Insights into ADAR1 RNA Editing, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-10-27T07:35:13Z date_published: 2024-10-29T00:00:00Z date_updated: 2026-04-07T13:23:59Z day: '29' ddc: - '572' degree_awarded: PhD department: - _id: GradSch - _id: CaBe doi: 10.15479/at:ista:18477 file: - access_level: closed checksum: 2053294ea4d770c495e4cc501e2a218b content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: bkaczmar date_created: 2024-10-29T11:56:36Z date_updated: 2025-10-29T23:30:02Z embargo_to: open_access file_id: '18485' file_name: 20241029_PhD_thesis_BKaczmarek.docx file_size: 23136626 relation: source_file - access_level: open_access checksum: 8ce857a4cd44b776791eaf180ac9dbb3 content_type: application/pdf creator: bkaczmar date_created: 2024-10-29T11:56:44Z date_updated: 2025-10-29T23:30:02Z embargo: 2025-10-29 file_id: '18486' file_name: 20241029_PhD_thesis_BKaczmarek.pdf file_size: 11707360 relation: main_file file_date_updated: 2025-10-29T23:30:02Z has_accepted_license: '1' language: - iso: eng month: '10' oa: 1 oa_version: Published Version page: '124' publication_identifier: isbn: - 978-3-99078-045-9 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Carrie A full_name: Bernecky, Carrie A id: 2CB9DFE2-F248-11E8-B48F-1D18A9856A87 last_name: Bernecky orcid: 0000-0003-0893-7036 title: Biochemical and structural insights into ADAR1 RNA editing 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: '2024' ... --- OA_place: publisher _id: '14821' abstract: - lang: eng text: "The hippocampus is central to memory formation, storage and retrieval over many\r\ntimescales. Neurons in this brain area are highly selective to spatial position as well as to many\r\nother variables of the environment. It is believed that the selectivity patterns of hippocampal\r\nneurons reflect the structure of tasks an animal performs. However, especially at timescales\r\nlonger than a few minutes or hours it is not fully known how these representations evolve, nor\r\nhow they map to behaviour in the process. In this thesis, I monitored the evolution of\r\nhippocampal representations in a novel spatial-associative memory task for rats. Reward\r\nlocations were associated with global sensory cues (i.e. context); animals had to remember the\r\nassociations and dig for food in those locations only. I used in vivo electrophysiology to record\r\nthe activity of the hippocampus dorsal CA1 neurons during the learning period of a few days.\r\nI report here a novel and simple method to classify behaviour performance to account\r\nfor individual variability in learning speed and spurious performance unrelated to true task rule\r\nlearning. Using this classification I was then able to investigate neural responses on different\r\nstages of learning matched across animals. On the first day of learning, I observed a fast\r\nformation of single-cell selectivity to task variables which remained stable over days. I also\r\nobserved that reward tuning was not a single process but dependent on task-related cognitive\r\nload. At the population level, a linear decoding approach revealed a hierarchy in the\r\nrepresentation of task variables that changed with learning. In the high-dimensional space of\r\npopulation activity, the representation of contexts was specific to each position in the maze, and\r\ncould thus be better decoded if the position was known. The decoding of position did not improve\r\nwith knowledge of other variables. As learning progressed, the hippocampal code underwent a\r\nreorganisation of high-variance directions in population activity, identified by principal\r\ncomponent analysis. I found that dominant dimensions started carrying increasing amounts of\r\ninformation about task context specifically at those positions where it mattered for task\r\nperformance. When I contrasted this with variables less relevant to task performance (e.g.\r\nmovement direction), I did not observe differences in decoding quality over positions nor a\r\nreduction of dimensionality with learning.\r\nOverall, the largest changes in CA1 neural response with task learning happened in a\r\nmatter of a few trials; over days, changes undetectable in single-cell statistics were responsible\r\nfor re-structuring the hierarchy of neural representations at the population level; these changes\r\nwere task-specific and reflected different stages of learning. This indicates that complex task\r\nlearning may involve different magnitudes of response modulation in CA1, which happen at\r\nspecific time scales linked to behaviour." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Heloisa full_name: Chiossi, Heloisa id: 2BBA502C-F248-11E8-B48F-1D18A9856A87 last_name: Chiossi orcid: 0009-0004-2973-278X citation: ama: Chiossi HSC. Adaptive hierarchical representations in the hippocampus. 2024. doi:10.15479/at:ista:14821 apa: Chiossi, H. S. C. (2024). Adaptive hierarchical representations in the hippocampus. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14821 chicago: Chiossi, Heloisa S. C. “Adaptive Hierarchical Representations in the Hippocampus.” Institute of Science and Technology Austria, 2024. https://doi.org/10.15479/at:ista:14821. ieee: H. S. C. Chiossi, “Adaptive hierarchical representations in the hippocampus,” Institute of Science and Technology Austria, 2024. ista: Chiossi HSC. 2024. Adaptive hierarchical representations in the hippocampus. Institute of Science and Technology Austria. mla: Chiossi, Heloisa S. C. Adaptive Hierarchical Representations in the Hippocampus. Institute of Science and Technology Austria, 2024, doi:10.15479/at:ista:14821. short: H.S.C. Chiossi, Adaptive Hierarchical Representations in the Hippocampus, Institute of Science and Technology Austria, 2024. corr_author: '1' date_created: 2024-01-16T14:25:21Z date_published: 2024-01-19T00:00:00Z date_updated: 2026-04-07T13:21:56Z day: '19' ddc: - '570' degree_awarded: PhD department: - _id: GradSch - _id: JoCs doi: 10.15479/at:ista:14821 ec_funded: 1 file: - access_level: closed checksum: d3fa3de1abd5af5204c13e9d55375615 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: hchiossi date_created: 2024-01-19T11:04:05Z date_updated: 2025-01-19T23:30:04Z embargo_to: open_access file_id: '14838' file_name: PhD_Thesis_190124.docx file_size: 8656268 relation: source_file - access_level: open_access checksum: 13adc8dcfb5b6b18107f89f0a98fa8bd content_type: application/pdf creator: hchiossi date_created: 2024-01-19T11:03:59Z date_updated: 2025-01-19T23:30:04Z embargo: 2025-01-19 file_id: '14839' file_name: PhD_Thesis_190124.pdf file_size: 6567275 relation: main_file file_date_updated: 2025-01-19T23:30:04Z has_accepted_license: '1' language: - iso: eng month: '01' oa: 1 oa_version: Published Version page: '89' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program publication_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Jozsef L full_name: Csicsvari, Jozsef L id: 3FA14672-F248-11E8-B48F-1D18A9856A87 last_name: Csicsvari orcid: 0000-0002-5193-4036 title: Adaptive hierarchical representations in the hippocampus type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2024' ...