---
OA_place: publisher
_id: '6266'
abstract:
- lang: eng
  text: 'A major challenge in neuroscience research is to dissect the circuits that
    orchestrate behavior in health and disease. Proteins from a wide range of non-mammalian
    species, such as microbial opsins, have been successfully transplanted to specific
    neuronal targets to override their natural communication patterns. The goal of
    our work is to manipulate synaptic communication in a manner that closely incorporates
    the functional intricacies of synapses by preserving temporal encoding (i.e. the
    firing pattern of the presynaptic neuron) and connectivity (i.e. target specific
    synapses rather than specific neurons). Our strategy to achieve this goal builds
    on the use of non-mammalian transplants to create a synthetic synapse. The mode
    of modulation comes from pre-synaptic uptake of a synthetic neurotransmitter (SN)
    into synaptic vesicles by means of a genetically targeted transporter selective
    for the SN. Upon natural vesicular release, exposure of the SN to the synaptic
    cleft will modify the post-synaptic potential through an orthogonal ligand gated
    ion channel. To achieve this goal we have functionally characterized a mixed cationic
    methionine-gated ion channel from Arabidopsis thaliana, designed a method to functionally
    characterize a synthetic transporter in isolated synaptic vesicles without the
    need for transgenic animals, identified and extracted multiple prokaryotic uptake
    systems that are substrate specific for methionine (Met), and established a primary/cell
    line co-culture system that would allow future combinatorial testing of this orthogonal
    transmitter-transporter-channel trifecta. Synthetic synapses will provide a unique
    opportunity to manipulate synaptic communication while maintaining the electrophysiological
    integrity of the pre-synaptic cell. In this way, information may be preserved
    that was generated in upstream circuits and that could be essential for concerted
    function and information processing. '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Catherine
  full_name: Mckenzie, Catherine
  id: 3EEDE19A-F248-11E8-B48F-1D18A9856A87
  last_name: Mckenzie
citation:
  ama: Mckenzie C. Design and characterization of methods and biological components
    to realize synthetic neurotransmission . 2018. doi:<a href="https://doi.org/10.15479/at:ista:th_1055">10.15479/at:ista:th_1055</a>
  apa: Mckenzie, C. (2018). <i>Design and characterization of methods and biological
    components to realize synthetic neurotransmission </i>. Institute of Science and
    Technology Austria. <a href="https://doi.org/10.15479/at:ista:th_1055">https://doi.org/10.15479/at:ista:th_1055</a>
  chicago: Mckenzie, Catherine. “Design and Characterization of Methods and Biological
    Components to Realize Synthetic Neurotransmission .” Institute of Science and
    Technology Austria, 2018. <a href="https://doi.org/10.15479/at:ista:th_1055">https://doi.org/10.15479/at:ista:th_1055</a>.
  ieee: C. Mckenzie, “Design and characterization of methods and biological components
    to realize synthetic neurotransmission ,” Institute of Science and Technology
    Austria, 2018.
  ista: Mckenzie C. 2018. Design and characterization of methods and biological components
    to realize synthetic neurotransmission . Institute of Science and Technology Austria.
  mla: Mckenzie, Catherine. <i>Design and Characterization of Methods and Biological
    Components to Realize Synthetic Neurotransmission </i>. Institute of Science and
    Technology Austria, 2018, doi:<a href="https://doi.org/10.15479/at:ista:th_1055">10.15479/at:ista:th_1055</a>.
  short: C. Mckenzie, Design and Characterization of Methods and Biological Components
    to Realize Synthetic Neurotransmission , Institute of Science and Technology Austria,
    2018.
corr_author: '1'
date_created: 2019-04-09T14:13:39Z
date_published: 2018-10-31T00:00:00Z
date_updated: 2026-04-08T14:14:05Z
day: '31'
ddc:
- '571'
- '573'
degree_awarded: PhD
department:
- _id: HaJa
doi: 10.15479/at:ista:th_1055
file:
- access_level: open_access
  checksum: 9d2c2dca04b00e485470c28b262af59a
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  creator: dernst
  date_created: 2019-04-09T14:12:40Z
  date_updated: 2021-02-11T11:17:16Z
  embargo: 2019-11-24
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  file_name: 2018_Thesis_McKenzie.pdf
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  creator: dernst
  date_created: 2019-04-09T14:12:40Z
  date_updated: 2020-07-14T12:47:25Z
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file_date_updated: 2021-02-11T11:17:16Z
has_accepted_license: '1'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '95'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
pubrep_id: '1055'
related_material:
  record:
  - id: '7132'
    relation: new_edition
    status: public
status: public
supervisor:
- first_name: Harald L
  full_name: Janovjak, Harald L
  id: 33BA6C30-F248-11E8-B48F-1D18A9856A87
  last_name: Janovjak
  orcid: 0000-0002-8023-9315
title: 'Design and characterization of methods and biological components to realize
  synthetic neurotransmission '
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2018'
...
---
OA_place: publisher
_id: '26'
abstract:
- lang: eng
  text: Expression of genes is a fundamental molecular phenotype that is subject to
    evolution by different types of mutations. Both the rate and the effect of mutations
    may depend on the DNA sequence context of a particular gene or a particular promoter
    sequence. In this thesis I investigate the nature of this dependence using simple
    genetic systems in Escherichia coli. With these systems I explore the evolution
    of constitutive gene expression from random starting sequences at different loci
    on the chromosome and at different locations in sequence space. First, I dissect
    chromosomal neighborhood effects that underlie locus-dependent differences in
    the potential of a gene under selection to become more highly expressed. Next,
    I find that the effects of point mutations in promoter sequences are dependent
    on sequence context, and that an existing energy matrix model performs poorly
    in predicting relative expression of unrelated sequences. Finally, I show that
    a substantial fraction of random sequences contain functional promoters and I
    present an extended thermodynamic model that predicts promoter strength in full
    sequence space. Taken together, these results provide new insights and guides
    on how to integrate information on sequence context to improve our qualitative
    and quantitative understanding of bacterial gene expression, with implications
    for rapid evolution of drug resistance, de novo evolution of genes, and horizontal
    gene transfer.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Magdalena
  full_name: Steinrück, Magdalena
  id: 2C023F40-F248-11E8-B48F-1D18A9856A87
  last_name: Steinrück
  orcid: 0000-0003-1229-9719
citation:
  ama: Steinrück M. The influence of sequence context on the evolution of bacterial
    gene expression. 2018. doi:<a href="https://doi.org/10.15479/AT:ISTA:th1059">10.15479/AT:ISTA:th1059</a>
  apa: Steinrück, M. (2018). <i>The influence of sequence context on the evolution
    of bacterial gene expression</i>. Institute of Science and Technology Austria.
    <a href="https://doi.org/10.15479/AT:ISTA:th1059">https://doi.org/10.15479/AT:ISTA:th1059</a>
  chicago: Steinrück, Magdalena. “The Influence of Sequence Context on the Evolution
    of Bacterial Gene Expression.” Institute of Science and Technology Austria, 2018.
    <a href="https://doi.org/10.15479/AT:ISTA:th1059">https://doi.org/10.15479/AT:ISTA:th1059</a>.
  ieee: M. Steinrück, “The influence of sequence context on the evolution of bacterial
    gene expression,” Institute of Science and Technology Austria, 2018.
  ista: Steinrück M. 2018. The influence of sequence context on the evolution of bacterial
    gene expression. Institute of Science and Technology Austria.
  mla: Steinrück, Magdalena. <i>The Influence of Sequence Context on the Evolution
    of Bacterial Gene Expression</i>. Institute of Science and Technology Austria,
    2018, doi:<a href="https://doi.org/10.15479/AT:ISTA:th1059">10.15479/AT:ISTA:th1059</a>.
  short: M. Steinrück, The Influence of Sequence Context on the Evolution of Bacterial
    Gene Expression, Institute of Science and Technology Austria, 2018.
corr_author: '1'
date_created: 2018-12-11T11:44:14Z
date_published: 2018-10-30T00:00:00Z
date_updated: 2026-04-08T14:15:35Z
day: '30'
ddc:
- '576'
- '579'
degree_awarded: PhD
department:
- _id: CaGu
doi: 10.15479/AT:ISTA:th1059
file:
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  checksum: 413cbce1cd1debeae3abe2a25dbc70d1
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  date_created: 2019-02-08T10:51:22Z
  date_updated: 2020-07-14T12:45:43Z
  embargo_to: open_access
  file_id: '5941'
  file_name: Thesis_Steinrueck_final.docx
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  relation: source_file
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  creator: dernst
  date_created: 2019-02-08T10:51:22Z
  date_updated: 2021-02-11T11:17:14Z
  embargo: 2019-11-02
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  file_name: Thesis_Steinrueck_final.pdf
  file_size: 7521973
  relation: main_file
file_date_updated: 2021-02-11T11:17:14Z
has_accepted_license: '1'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '109'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '8029'
pubrep_id: '1059'
related_material:
  record:
  - id: '704'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Calin C
  full_name: Guet, Calin C
  id: 47F8433E-F248-11E8-B48F-1D18A9856A87
  last_name: Guet
  orcid: 0000-0001-6220-2052
title: The influence of sequence context on the evolution of bacterial gene expression
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2018'
...
---
OA_place: publisher
_id: '50'
abstract:
- lang: eng
  text: The Wnt/planar cell polarity (Wnt/PCP) pathway determines planar polarity
    of epithelial cells in both vertebrates and invertebrates. The role that Wnt/PCP
    signaling plays in mesenchymal contexts, however, is only poorly understood. While
    previous studies have demonstrated the capacity of Wnt/PCP signaling to polarize
    and guide directed migration of mesenchymal cells, it remains unclear whether
    endogenous Wnt/PCP signaling performs these functions instructively, as it does
    in epithelial cells. Here we developed a light-switchable version of the Wnt/PCP
    receptor Frizzled 7 (Fz7) to unambiguously distinguish between an instructive
    and a permissive role of Wnt/PCP signaling for the directional collective migration
    of mesendoderm progenitor cells during zebrafish gastrulation. We show that prechordal
    plate (ppl) cell migration is defective in maternal-zygotic fz7a and fz7b (MZ
    fz7a,b) double mutant embryos, and that Fz7 functions cell-autonomously in this
    process by promoting ppl cell protrusion formation and directed migration. We
    further show that local activation of Fz7 can direct ppl cell migration both in
    vitro and in vivo. Surprisingly, however, uniform Fz7 activation is sufficient
    to fully rescue the ppl cell migration defect in MZ fz7a,b mutant embryos, indicating
    that Wnt/PCP signaling functions permissively rather than instructively in directed
    mesendoderm cell migration during zebrafish gastrulation.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Daniel
  full_name: Capek, Daniel
  id: 31C42484-F248-11E8-B48F-1D18A9856A87
  last_name: Capek
  orcid: 0000-0001-5199-9940
citation:
  ama: Capek D. Optogenetic Frizzled 7 reveals a permissive function of Wnt/PCP signaling
    in directed mesenchymal cell migration. 2018. doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_1031">10.15479/AT:ISTA:TH_1031</a>
  apa: Capek, D. (2018). <i>Optogenetic Frizzled 7 reveals a permissive function of
    Wnt/PCP signaling in directed mesenchymal cell migration</i>. Institute of Science
    and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:TH_1031">https://doi.org/10.15479/AT:ISTA:TH_1031</a>
  chicago: Capek, Daniel. “Optogenetic Frizzled 7 Reveals a Permissive Function of
    Wnt/PCP Signaling in Directed Mesenchymal Cell Migration.” Institute of Science
    and Technology Austria, 2018. <a href="https://doi.org/10.15479/AT:ISTA:TH_1031">https://doi.org/10.15479/AT:ISTA:TH_1031</a>.
  ieee: D. Capek, “Optogenetic Frizzled 7 reveals a permissive function of Wnt/PCP
    signaling in directed mesenchymal cell migration,” Institute of Science and Technology
    Austria, 2018.
  ista: Capek D. 2018. Optogenetic Frizzled 7 reveals a permissive function of Wnt/PCP
    signaling in directed mesenchymal cell migration. Institute of Science and Technology
    Austria.
  mla: Capek, Daniel. <i>Optogenetic Frizzled 7 Reveals a Permissive Function of Wnt/PCP
    Signaling in Directed Mesenchymal Cell Migration</i>. Institute of Science and
    Technology Austria, 2018, doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_1031">10.15479/AT:ISTA:TH_1031</a>.
  short: D. Capek, Optogenetic Frizzled 7 Reveals a Permissive Function of Wnt/PCP
    Signaling in Directed Mesenchymal Cell Migration, Institute of Science and Technology
    Austria, 2018.
corr_author: '1'
date_created: 2018-12-11T11:44:21Z
date_published: 2018-06-22T00:00:00Z
date_updated: 2026-04-16T10:07:33Z
day: '22'
ddc:
- '570'
- '591'
- '596'
degree_awarded: PhD
department:
- _id: CaHe
doi: 10.15479/AT:ISTA:TH_1031
file:
- access_level: open_access
  checksum: d3eca3dcacb67bffdde6e6609c31cdd0
  content_type: application/pdf
  creator: dernst
  date_created: 2019-04-08T13:42:26Z
  date_updated: 2021-02-11T11:17:17Z
  embargo: 2019-06-25
  file_id: '6238'
  file_name: 2018_Thesis_Capek.pdf
  file_size: 31576521
  relation: main_file
- access_level: closed
  checksum: 876deb14067e638aba65d209668bd821
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: dernst
  date_created: 2019-04-08T13:42:27Z
  date_updated: 2021-02-11T23:30:21Z
  embargo_to: open_access
  file_id: '6239'
  file_name: 2018_Thesis_Capek_source.docx
  file_size: 38992956
  relation: source_file
file_date_updated: 2021-02-11T23:30:21Z
has_accepted_license: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: '95'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '8004'
pubrep_id: '1031'
related_material:
  record:
  - id: '661'
    relation: part_of_dissertation
    status: public
  - id: '1100'
    relation: part_of_dissertation
    status: public
  - id: '676'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Carl-Philipp J
  full_name: Heisenberg, Carl-Philipp J
  id: 39427864-F248-11E8-B48F-1D18A9856A87
  last_name: Heisenberg
  orcid: 0000-0002-0912-4566
title: Optogenetic Frizzled 7 reveals a permissive function of Wnt/PCP signaling in
  directed mesenchymal cell migration
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2018'
...
---
OA_place: publisher
_id: '820'
abstract:
- lang: eng
  text: "The lac operon is a classic model system for bacterial gene regulation, and
    has been studied extensively in E. coli, a classic model organism. However, not
    much is known about E. coli’s ecology and life outside the laboratory, in particular
    in soil and water environments. The natural diversity of the lac operon outside
    the laboratory, its role in the ecology of E. coli and the selection pressures
    it is exposed to, are similarly unknown.\r\nIn Chapter Two of this thesis, I explore
    the genetic diversity, phylogenetic history and signatures of selection of the
    lac operon across 20 natural isolates of E. coli and divergent clades of Escherichia.
    I found that complete lac operons were present in all isolates examined, which
    in all but one case were functional. The lac operon phylogeny conformed to the
    whole-genome phylogeny of the divergent Escherichia clades, which excludes horizontal
    gene transfer as an explanation for the presence of functional lac operons in
    these clades. All lac operon genes showed a signature of purifying selection;
    this signature was strongest for the lacY gene. Lac operon genes of human and
    environmental isolates showed similar signatures of selection, except the lacZ
    gene, which showed a stronger signature of selection in environmental isolates.\r\nIn
    Chapter Three, I try to identify the natural genetic variation relevant for phenotype
    and fitness in the lac operon, comparing growth rate on lactose and LacZ activity
    of the lac operons of these wild isolates in a common genetic background. Sequence
    variation in the lac promoter region, upstream of the -10 and -35 RNA polymerase
    binding motif, predicted variation in LacZ activity at full induction, using a
    thermodynamic model of polymerase binding (Tugrul, 2016). However, neither variation
    in LacZ activity, nor RNA polymerase binding predicted by the model correlated
    with variation in growth rate. Lac operons of human and environmental isolates
    did not differ systematically in either growth rate on lactose or LacZ protein
    activity, suggesting that these lac operons have been exposed to similar selection
    pressures. We thus have no evidence that the phenotypic variation we measured
    is relevant for fitness.\r\nTo start assessing the effect of genomic background
    on the growth phenotype conferred by the lac operon, I compared growth on minimal
    medium with lactose between lac operon constructs and the corresponding original
    isolates, I found that maximal growth rate was determined by genomic background,
    with almost all backgrounds conferring higher growth rates than lab strain K12
    MG1655. However, I found no evidence that the lactose concentration at which growth
    was half maximal depended on genomic background."
acknowledgement: "ERC H2020 programme (grant agreement no. 648440)\r\nThanks to Jon
  Bollback for giving me the chance to do this work, for sharing the ideas that lay
  at the basis of this work, for his honesty and openness, showing himself to me as
  a person and not just as a boss. Thanks to Nick Barton for his guidance at the last
  stage, reading and commenting extensively on several versions of this manuscript,
  and for his encouragement; thanks to both Jon and Nick for their kindness and patience.
  Thanks to Erik van Nimwegen and Calin Guet for their time and willingness to be
  in my thesis committee, and to Erik van Nimwegen especially for agreeing to enter
  my thesis committee at the last moment, and for his very sharp, helpful and relevant
  comments during and after the defense. Thanks to my collaborators and discussion
  partners: Anne Kupczok, for her guidance, ideas and discussions during the construction
  of the manuscript of Chapter Two, and her comments on the manuscript; Georg Rieckh
  for making me aware of the issue of parameter identifiability, suggesting how to
  solve it, and for his unfortunate idea to start the plasmid enterprise in the first
  place; Murat Tugrul for sharing his model, for his enthusiasm, and his comments
  on Chapter Three; Srdjan Sarikas for his collaboration on the Monod model fitting,
  fast forwarding the analysis to turbo speed and making beautiful figures, and making
  the discussion fun on top of it all; Vanessa Barone for her last minute comments,
  especially on Chapter Three, providing a sharp and very helpful experimentalist
  perspective at the last moment; Maros Pleska and Marjon de Vos for their comments
  on the manuscript of Chapter Two; Gasper Tkacik for his crucial input on the relation
  between growth rate and lactose concentration; Bor Kavcic for his input on growth
  rate modeling and error propagation. Thanks to the Bollback, Bollenbach, Barton,
  Guet and Tkacik group members for both pro- viding an inspiring and supportive scientific
  environment to work in, as well as a lot of warmth and colour to everyday life.
  And thanks to the friends I found here, to the people who were there for me and
  to the people who changed my life, making it stranger and more beautiful than I
  could have imagined, Maros, Vanessa, Tade, Suzi, Andrej, Peter, Tiago, Kristof,
  Karin, Irene, Misha, Mato, Guillaume and Zanin. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Fabienne
  full_name: Jesse, Fabienne
  id: 4C8C26A4-F248-11E8-B48F-1D18A9856A87
  last_name: Jesse
citation:
  ama: Jesse F. The lac operon in the wild. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_857">10.15479/AT:ISTA:th_857</a>
  apa: Jesse, F. (2017). <i>The lac operon in the wild</i>. Institute of Science and
    Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_857">https://doi.org/10.15479/AT:ISTA:th_857</a>
  chicago: Jesse, Fabienne. “The Lac Operon in the Wild.” Institute of Science and
    Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_857">https://doi.org/10.15479/AT:ISTA:th_857</a>.
  ieee: F. Jesse, “The lac operon in the wild,” Institute of Science and Technology
    Austria, 2017.
  ista: Jesse F. 2017. The lac operon in the wild. Institute of Science and Technology
    Austria.
  mla: Jesse, Fabienne. <i>The Lac Operon in the Wild</i>. Institute of Science and
    Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_857">10.15479/AT:ISTA:th_857</a>.
  short: F. Jesse, The Lac Operon in the Wild, Institute of Science and Technology
    Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:41Z
date_published: 2017-08-25T00:00:00Z
date_updated: 2026-04-08T14:18:16Z
day: '25'
ddc:
- '576'
- '577'
- '579'
degree_awarded: PhD
department:
- _id: JoBo
doi: 10.15479/AT:ISTA:th_857
ec_funded: 1
file:
- access_level: open_access
  checksum: c62257a7bff0c5f39e1abffc6bfcca5c
  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:17:00Z
  date_updated: 2020-07-14T12:48:10Z
  file_id: '5252'
  file_name: IST-2017-857-v1+1_thesis_fabienne.pdf
  file_size: 3417773
  relation: main_file
- access_level: closed
  checksum: fc87d7d72fce52824a3ae7dcad0413a8
  content_type: application/x-tex
  creator: dernst
  date_created: 2019-04-05T08:51:59Z
  date_updated: 2020-07-14T12:48:10Z
  file_id: '6212'
  file_name: 2017_thesis_Jesse_source.tex
  file_size: 215899
  relation: source_file
file_date_updated: 2020-07-14T12:48:10Z
has_accepted_license: '1'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
page: '87'
project:
- _id: 2578D616-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '648440'
  name: Selective Barriers to Horizontal Gene Transfer
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6829'
pubrep_id: '857'
status: public
supervisor:
- first_name: Jonathan P
  full_name: Bollback, Jonathan P
  id: 2C6FA9CC-F248-11E8-B48F-1D18A9856A87
  last_name: Bollback
  orcid: 0000-0002-4624-4612
title: The lac operon in the wild
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: '2017'
...
---
OA_place: publisher
_id: '1127'
abstract:
- lang: eng
  text: "Plant hormone auxin and its transport between cells belong to the most important\r\nmechanisms
    controlling plant development. Auxin itself could change localization of PINs
    and\r\nthereby control direction of its own flow. We performed an expression profiling
    experiment\r\nin Arabidopsis roots to identify potential regulators of PIN polarity
    which are transcriptionally\r\nregulated by auxin signalling. We identified several
    novel regulators and performed a detailed\r\ncharacterization of the transcription
    factor WRKY23 (At2g47260) and its role in auxin\r\nfeedback on PIN polarity. Gain-of-function
    and dominant-negative mutants revealed that\r\nWRKY23 plays a crucial role in
    mediating the auxin effect on PIN polarity. In concordance,\r\ntypical polar auxin
    transport processes such as gravitropism and leaf vascular pattern\r\nformation
    were disturbed by interfering with WRKY23 function.\r\nIn order to identify direct
    targets of WRKY23, we performed consequential expression\r\nprofiling experiments
    using a WRKY23 inducible gain-of-function line and dominant-negative\r\nWRKY23
    line that is defunct in PIN re-arrangement. Among several genes mostly related
    to\r\nthe groups of cell wall and defense process regulators, we identified LYSINE-HISTIDINE\r\nTRANSPORTER
    1 (LHT1; At5g40780), a small amino acid permease gene from the amino\r\nacid/auxin
    permease family (AAAP), we present its detailed characterisation in auxin feedback\r\non
    PIN repolarization, identified its transcriptional regulation, we propose a potential\r\nmechanism
    of its action. Moreover, we identified also a member of receptor-like protein\r\nkinase
    LRR-RLK (LEUCINE-RICH REPEAT TRANSMEMBRANE PROTEIN KINASE PROTEIN 1;\r\nLRRK1;
    At1g05700), which also affects auxin-dependent PIN re-arrangement. We described\r\nits
    transcriptional behaviour, subcellular localization. Based on global expression
    data, we\r\ntried to identify ligand responsible for mechanism of signalling and
    suggest signalling partner\r\nand interactors. Additionally, we described role
    of novel phytohormone group, strigolactone,\r\nin auxin-dependent PIN re-arrangement,
    that could be a fundament for future studies in this\r\nfield.\r\nOur results
    provide first insights into an auxin transcriptional network targeting PIN\r\nlocalization
    and thus regulating plant development. We highlighted WRKY23 transcriptional\r\nnetwork
    and characterised its mediatory role in plant development. We identified direct\r\neffectors
    of this network, LHT1 and LRRK1, and describe their roles in PIN re-arrangement
    and\r\nPIN-dependent auxin transport processes."
acknowledgement: I would like to first acknowledge my supervisor Jiří Friml for support,
  kind advice and patience. It was a pleasure to be a part of your lab, Jiří. I will
  remember the atmosphere present in auxin lab at VIB in Ghent and at IST in Klosterneuburg
  forever. I would like to thank all past and present lab members for the friendship
  and friendly and scientific environment in the groups. It was so nice to cooperate
  with you, guys. There was always someone who helped me with experiments, troubleshoot
  issues coming from our work etc. At this place, I would like to thank especially
  to Gergo Molnár. I’m happy (and lucky) that I have met him; he naturally became
  my tutor and guide through my PhD. From no one else during my entire professional
  career, I’ve learned that much.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Tomas
  full_name: Prat, Tomas
  id: 3DA3BFEE-F248-11E8-B48F-1D18A9856A87
  last_name: Prat
citation:
  ama: Prat T. Identification of novel regulators of PIN polarity and development
    of novel auxin sensor. 2017.
  apa: Prat, T. (2017). <i>Identification of novel regulators of PIN polarity and
    development of novel auxin sensor</i>. Institute of Science and Technology Austria.
  chicago: Prat, Tomas. “Identification of Novel Regulators of PIN Polarity and Development
    of Novel Auxin Sensor.” Institute of Science and Technology Austria, 2017.
  ieee: T. Prat, “Identification of novel regulators of PIN polarity and development
    of novel auxin sensor,” Institute of Science and Technology Austria, 2017.
  ista: Prat T. 2017. Identification of novel regulators of PIN polarity and development
    of novel auxin sensor. Institute of Science and Technology Austria.
  mla: Prat, Tomas. <i>Identification of Novel Regulators of PIN Polarity and Development
    of Novel Auxin Sensor</i>. Institute of Science and Technology Austria, 2017.
  short: T. Prat, Identification of Novel Regulators of PIN Polarity and Development
    of Novel Auxin Sensor, Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:50:17Z
date_published: 2017-01-12T00:00:00Z
date_updated: 2026-04-08T14:17:39Z
day: '12'
ddc:
- '580'
degree_awarded: PhD
department:
- _id: JiFr
file:
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file_date_updated: 2021-02-22T11:52:56Z
has_accepted_license: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: '131'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6233'
related_material:
  record:
  - id: '449'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Jiří
  full_name: Friml, Jiří
  id: 4159519E-F248-11E8-B48F-1D18A9856A87
  last_name: Friml
  orcid: 0000-0002-8302-7596
title: Identification of novel regulators of PIN polarity and development of novel
  auxin sensor
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '992'
abstract:
- lang: eng
  text: "An instance of the Constraint Satisfaction Problem (CSP) is given by a finite
    set of\r\nvariables, a finite domain of labels, and a set of constraints, each
    constraint acting on\r\na subset of the variables. The goal is to find an assignment
    of labels to its variables\r\nthat satisfies all constraints (or decide whether
    one exists). If we allow more general\r\n“soft” constraints, which come with (possibly
    infinite) costs of particular assignments,\r\nwe obtain instances from a richer
    class called Valued Constraint Satisfaction Problem\r\n(VCSP). There the goal
    is to find an assignment with minimum total cost.\r\nIn this thesis, we focus
    (assuming that P\r\n6\r\n=\r\nNP) on classifying computational com-\r\nplexity
    of CSPs and VCSPs under certain restricting conditions. Two results are the core\r\ncontent
    of the work. In one of them, we consider VCSPs parametrized by a constraint\r\nlanguage,
    that is the set of “soft” constraints allowed to form the instances, and finish\r\nthe
    complexity classification modulo (missing pieces of) complexity classification
    for\r\nanalogously parametrized CSP. The other result is a generalization of Edmonds’
    perfect\r\nmatching algorithm. This generalization contributes to complexity classfications
    in two\r\nways. First, it gives a new (largest known) polynomial-time solvable
    class of Boolean\r\nCSPs in which every variable may appear in at most two constraints
    and second, it\r\nsettles full classification of Boolean CSPs with planar drawing
    (again parametrized by a\r\nconstraint language)."
acknowledgement: FP7/2007-2013/ERC grant agreement no 616160
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Michal
  full_name: Rolinek, Michal
  id: 3CB3BC06-F248-11E8-B48F-1D18A9856A87
  last_name: Rolinek
citation:
  ama: Rolinek M. Complexity of constraint satisfaction. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_815">10.15479/AT:ISTA:th_815</a>
  apa: Rolinek, M. (2017). <i>Complexity of constraint satisfaction</i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_815">https://doi.org/10.15479/AT:ISTA:th_815</a>
  chicago: Rolinek, Michal. “Complexity of Constraint Satisfaction.” Institute of
    Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_815">https://doi.org/10.15479/AT:ISTA:th_815</a>.
  ieee: M. Rolinek, “Complexity of constraint satisfaction,” Institute of Science
    and Technology Austria, 2017.
  ista: Rolinek M. 2017. Complexity of constraint satisfaction. Institute of Science
    and Technology Austria.
  mla: Rolinek, Michal. <i>Complexity of Constraint Satisfaction</i>. Institute of
    Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_815">10.15479/AT:ISTA:th_815</a>.
  short: M. Rolinek, Complexity of Constraint Satisfaction, Institute of Science and
    Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:49:35Z
date_published: 2017-05-01T00:00:00Z
date_updated: 2026-04-08T14:17:06Z
day: '01'
ddc:
- '004'
degree_awarded: PhD
department:
- _id: VlKo
doi: 10.15479/AT:ISTA:th_815
ec_funded: 1
file:
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has_accepted_license: '1'
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
page: '97'
project:
- _id: 25FBA906-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '616160'
  name: 'Discrete Optimization in Computer Vision: Theory and Practice'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6407'
pubrep_id: '815'
status: public
supervisor:
- first_name: Vladimir
  full_name: Kolmogorov, Vladimir
  id: 3D50B0BA-F248-11E8-B48F-1D18A9856A87
  last_name: Kolmogorov
title: Complexity of constraint satisfaction
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '6291'
abstract:
- lang: eng
  text: Bacteria and their pathogens – phages – are the most abundant living entities
    on Earth. Throughout their coevolution, bacteria have evolved multiple immune
    systems to overcome the ubiquitous threat from the phages. Although the molecu-
    lar details of these immune systems’ functions are relatively well understood,
    their epidemiological consequences for the phage-bacterial communities have been
    largely neglected. In this thesis we employed both experimental and theoretical
    methods to explore whether herd and social immunity may arise in bacterial popu-
    lations. Using our experimental system consisting of Escherichia coli strains
    with a CRISPR based immunity to the T7 phage we show that herd immunity arises
    in phage-bacterial communities and that it is accentuated when the populations
    are spatially structured. By fitting a mathematical model, we inferred expressions
    for the herd immunity threshold and the velocity of spread of a phage epidemic
    in partially resistant bacterial populations, which both depend on the bacterial
    growth rate, phage burst size and phage latent period. We also investigated the
    poten- tial for social immunity in Streptococcus thermophilus and its phage 2972
    using a bioinformatic analysis of potentially coding short open reading frames
    with a signalling signature, encoded within the CRISPR associated genes. Subsequently,
    we tested one identified potentially signalling peptide and found that its addition
    to a phage-challenged culture increases probability of survival of bacteria two
    fold, although the results were only marginally significant. Together, these results
    demonstrate that the ubiquitous arms races between bacteria and phages have further
    consequences at the level of the population.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Pavel
  full_name: Payne, Pavel
  id: 35F78294-F248-11E8-B48F-1D18A9856A87
  last_name: Payne
  orcid: 0000-0002-2711-9453
citation:
  ama: Payne P. Bacterial herd and social immunity to phages. 2017.
  apa: Payne, P. (2017). <i>Bacterial herd and social immunity to phages</i>. Institute
    of Science and Technology Austria.
  chicago: Payne, Pavel. “Bacterial Herd and Social Immunity to Phages.” Institute
    of Science and Technology Austria, 2017.
  ieee: P. Payne, “Bacterial herd and social immunity to phages,” Institute of Science
    and Technology Austria, 2017.
  ista: Payne P. 2017. Bacterial herd and social immunity to phages. Institute of
    Science and Technology Austria.
  mla: Payne, Pavel. <i>Bacterial Herd and Social Immunity to Phages</i>. Institute
    of Science and Technology Austria, 2017.
  short: P. Payne, Bacterial Herd and Social Immunity to Phages, Institute of Science
    and Technology Austria, 2017.
corr_author: '1'
date_created: 2019-04-09T15:16:45Z
date_published: 2017-02-01T00:00:00Z
date_updated: 2026-04-08T14:16:28Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: NiBa
- _id: JoBo
file:
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  checksum: a0fc5c26a89c0ea759947ffba87d0d8f
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  creator: dernst
  date_created: 2019-04-09T15:15:32Z
  date_updated: 2020-07-14T12:47:27Z
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  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T13:45:59Z
  date_updated: 2021-02-22T13:45:59Z
  file_id: '9187'
  file_name: 2017_Payne_Thesis.pdf
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  relation: main_file
  success: 1
file_date_updated: 2021-02-22T13:45:59Z
has_accepted_license: '1'
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
page: '83'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Jonathan P
  full_name: Bollback, Jonathan P
  id: 2C6FA9CC-F248-11E8-B48F-1D18A9856A87
  last_name: Bollback
  orcid: 0000-0002-4624-4612
- first_name: Nicholas H
  full_name: Barton, Nicholas H
  id: 4880FE40-F248-11E8-B48F-1D18A9856A87
  last_name: Barton
  orcid: 0000-0002-8548-5240
title: Bacterial herd and social immunity to phages
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '837'
abstract:
- lang: eng
  text: 'The hippocampus is a key brain region for memory and notably for spatial
    memory, and is needed for both spatial working and reference memories. Hippocampal
    place cells selectively discharge in specific locations of the environment to
    form mnemonic represen tations of space. Several behavioral protocols have been
    designed to test spatial memory which requires the experimental subject to utilize
    working memory and reference memory. However, less is known about how these memory
    traces are presented in the hippo campus, especially considering tasks that require
    both spatial working and long -term reference memory demand. The aim of my thesis
    was to elucidate how spatial working memory, reference memory, and the combination
    of both are represented in the hippocampus. In this thesis, using a radial eight
    -arm maze, I examined how the combined demand on these memories influenced place
    cell assemblies while reference memories were partially updated by changing some
    of the reward- arms. This was contrasted with task varian ts requiring working
    or reference memories only. Reference memory update led to gradual place field
    shifts towards the rewards on the switched arms. Cells developed enhanced firing
    in passes between newly -rewarded arms as compared to those containing an unchanged
    reward. The working memory task did not show such gradual changes. Place assemblies
    on occasions replayed trajectories of the maze; at decision points the next arm
    choice was preferentially replayed in tasks needing reference memory while in
    the pure working memory task the previously visited arm was replayed. Hence trajectory
    replay only reflected the decision of the animal in tasks needing reference memory
    update. At the reward locations, in all three tasks outbound trajectories of the
    current arm were preferentially replayed, showing the animals’ next path to the
    center. At reward locations trajectories were replayed preferentially in reverse
    temporal order. Moreover, in the center reverse replay was seen in the working
    memory task but in the other tasks forward replay was seen. Hence, the direction
    of reactivation was determined by the goal locations so that part of the trajectory
    which was closer to the goal was reactivated later in an HSE while places further
    away from the goal were reactivated earlier. Altogether my work demonstrated that
    reference memory update triggers several levels of reorganization of the hippocampal
    cognitive map which are not seen in simpler working memory demand s. Moreover,
    hippocampus is likely to be involved in spatial decisions through reactivating
    planned trajectories when reference memory recall is required for such a decision. '
acknowledgement: 'I am very grateful for the opportunity I have had as a graduate
  student to explore and incredibly interesting branch of neuroscience, and for the
  people who made it possible. Firstly, I would like to offer my thanks to my supervisor
  Professor Jozsef Csicsvari for his great support, guidance and patience offered
  over the years. The door to his office was always open whenever I had questions.
  I have learned a lot from him about carefully designing experiments, asking interesting
  questions and how to integrate results into a broader picture. I also express my
  gratitude to the remarkable post- doc , Dr. Joseph O’Neill. He is a gre at scientific
  role model who is always willing to teach , and advice and talk through problems
  with his full attention. Many thanks to my wonderful “office mates” over the years
  and their support and encouragement, Alice Avernhe, Philipp Schönenberger, Desiree
  Dickerson, Karel Blahna, Charlotte Boccara, Igor Gridchyn, Peter Baracskay, Krisztián
  Kovács, Dámaris Rangel, Karola Käfer and Federico Stella. They were the ones in
  the lab for the many useful discussions about science and for making the laboratory
  such a nice and friendly place to work in. A special thank goes to Michael LoBianco
  and Jago Wallenschus for wonderful technical support. I would also like to thank
  Professor Peter Jonas and Professor David M Bannerman for being my qualifying exam
  and thesi s committee members despite their busy schedule. I am also very thankful
  to IST Austria for their support all throughout my PhD. '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Haibing
  full_name: Xu, Haibing
  id: 310349D0-F248-11E8-B48F-1D18A9856A87
  last_name: Xu
citation:
  ama: Xu H. Reactivation of the hippocampal cognitive map in goal-directed spatial
    tasks. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_858">10.15479/AT:ISTA:th_858</a>
  apa: Xu, H. (2017). <i>Reactivation of the hippocampal cognitive map in goal-directed
    spatial tasks</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_858">https://doi.org/10.15479/AT:ISTA:th_858</a>
  chicago: Xu, Haibing. “Reactivation of the Hippocampal Cognitive Map in Goal-Directed
    Spatial Tasks.” Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_858">https://doi.org/10.15479/AT:ISTA:th_858</a>.
  ieee: H. Xu, “Reactivation of the hippocampal cognitive map in goal-directed spatial
    tasks,” Institute of Science and Technology Austria, 2017.
  ista: Xu H. 2017. Reactivation of the hippocampal cognitive map in goal-directed
    spatial tasks. Institute of Science and Technology Austria.
  mla: Xu, Haibing. <i>Reactivation of the Hippocampal Cognitive Map in Goal-Directed
    Spatial Tasks</i>. Institute of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_858">10.15479/AT:ISTA:th_858</a>.
  short: H. Xu, Reactivation of the Hippocampal Cognitive Map in Goal-Directed Spatial
    Tasks, Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:46Z
date_published: 2017-08-23T00:00:00Z
date_updated: 2026-04-08T14:18:55Z
day: '23'
ddc:
- '571'
degree_awarded: PhD
department:
- _id: JoCs
doi: 10.15479/AT:ISTA:th_858
file:
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has_accepted_license: '1'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
page: '93'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6811'
pubrep_id: '858'
related_material:
  record:
  - id: '5828'
    relation: part_of_dissertation
    status: public
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: Reactivation of the hippocampal cognitive map in goal-directed spatial tasks
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: '2017'
...
---
OA_place: publisher
_id: '838'
abstract:
- lang: eng
  text: 'In this thesis we discuss the exact security of message authentications codes
    HMAC , NMAC , and PMAC . NMAC is a mode of operation which turns a fixed input-length
    keyed hash function f into a variable input-length function. A practical single-key
    variant of NMAC called HMAC is a very popular and widely deployed message authentication
    code (MAC). PMAC is a block-cipher based mode of operation, which also happens
    to be the most famous fully parallel MAC. NMAC was introduced by Bellare, Canetti
    and Krawczyk Crypto’96, who proved it to be a secure pseudorandom function (PRF),
    and thus also a MAC, under two assumptions. Unfortunately, for many instantiations
    of HMAC one of them has been found to be wrong. To restore the provable guarantees
    for NMAC , Bellare [Crypto’06] showed its security without this assumption. PMAC
    was introduced by Black and Rogaway at Eurocrypt 2002. If instantiated with a
    pseudorandom permutation over n -bit strings, PMAC constitutes a provably secure
    variable input-length PRF. For adversaries making q queries, each of length at
    most ` (in n -bit blocks), and of total length σ ≤ q` , the original paper proves
    an upper bound on the distinguishing advantage of O ( σ 2 / 2 n ), while the currently
    best bound is O ( qσ/ 2 n ). In this work we show that this bound is tight by
    giving an attack with advantage Ω( q 2 `/ 2 n ). In the PMAC construction one
    initially XORs a mask to every message block, where the mask for the i th block
    is computed as τ i := γ i · L , where L is a (secret) random value, and γ i is
    the i -th codeword of the Gray code. Our attack applies more generally to any
    sequence of γ i ’s which contains a large coset of a subgroup of GF (2 n ). As
    for NMAC , our first contribution is a simpler and uniform proof: If f is an ε
    -secure PRF (against q queries) and a δ - non-adaptively secure PRF (against q
    queries), then NMAC f is an ( ε + `qδ )-secure PRF against q queries of length
    at most ` blocks each. We also show that this ε + `qδ bound is basically tight
    by constructing an f for which an attack with advantage `qδ exists. Moreover,
    we analyze the PRF-security of a modification of NMAC called NI by An and Bellare
    that avoids the constant rekeying on multi-block messages in NMAC and allows for
    an information-theoretic analysis. We carry out such an analysis, obtaining a
    tight `q 2 / 2 c bound for this step, improving over the trivial bound of ` 2
    q 2 / 2 c . Finally, we investigate, if the security of PMAC can be further improved
    by using τ i ’s that are k -wise independent, for k &gt; 1 (the original has k
    = 1). We observe that the security of PMAC will not increase in general if k =
    2, and then prove that the security increases to O ( q 2 / 2 n ), if the k = 4.
    Due to simple extension attacks, this is the best bound one can hope for, using
    any distribution on the masks. Whether k = 3 is already sufficient to get this
    level of security is left as an open problem. Keywords: Message authentication
    codes, Pseudorandom functions, HMAC, PMAC. '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Michal
  full_name: Rybar, Michal
  id: 2B3E3DE8-F248-11E8-B48F-1D18A9856A87
  last_name: Rybar
citation:
  ama: Rybar M. (The exact security of) Message authentication codes. 2017. doi:<a
    href="https://doi.org/10.15479/AT:ISTA:th_828">10.15479/AT:ISTA:th_828</a>
  apa: Rybar, M. (2017). <i>(The exact security of) Message authentication codes</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_828">https://doi.org/10.15479/AT:ISTA:th_828</a>
  chicago: Rybar, Michal. “(The Exact Security of) Message Authentication Codes.”
    Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_828">https://doi.org/10.15479/AT:ISTA:th_828</a>.
  ieee: M. Rybar, “(The exact security of) Message authentication codes,” Institute
    of Science and Technology Austria, 2017.
  ista: Rybar M. 2017. (The exact security of) Message authentication codes. Institute
    of Science and Technology Austria.
  mla: Rybar, Michal. <i>(The Exact Security of) Message Authentication Codes</i>.
    Institute of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_828">10.15479/AT:ISTA:th_828</a>.
  short: M. Rybar, (The Exact Security of) Message Authentication Codes, Institute
    of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:46Z
date_published: 2017-06-26T00:00:00Z
date_updated: 2026-04-08T14:18:39Z
day: '26'
ddc:
- '000'
degree_awarded: PhD
department:
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publist_id: '6810'
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status: public
title: (The exact security of) Message authentication codes
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '6287'
abstract:
- lang: eng
  text: The main objects considered in the present work are simplicial and CW-complexes
    with vertices forming a random point cloud. In particular, we consider a Poisson
    point process in R^n and study Delaunay and Voronoi complexes of the first and
    higher orders and weighted Delaunay complexes obtained as sections of Delaunay
    complexes, as well as the Čech complex. Further, we examine theDelaunay complex
    of a Poisson point process on the sphere S^n, as well as of a uniform point cloud,
    which is equivalent to the convex hull, providing a connection to the theory of
    random polytopes. Each of the complexes in question can be endowed with a radius
    function, which maps its cells to the radii of appropriately chosen circumspheres,
    called the radius of the cell. Applying and developing discrete Morse theory for
    these functions, joining it together with probabilistic and sometimes analytic
    machinery, and developing several integral geometric tools, we aim at getting
    the distributions of circumradii of typical cells. For all considered complexes,
    we are able to generalize and obtain up to constants the distribution of radii
    of typical intervals of all types. In low dimensions the constants can be computed
    explicitly, thus providing the explicit expressions for the expected numbers of
    cells. In particular, it allows to find the expected density of simplices of every
    dimension for a Poisson point process in R^4, whereas the result for R^3 was known
    already in 1970's.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Anton
  full_name: Nikitenko, Anton
  id: 3E4FF1BA-F248-11E8-B48F-1D18A9856A87
  last_name: Nikitenko
  orcid: 0000-0002-0659-3201
citation:
  ama: Nikitenko A. Discrete Morse theory for random complexes . 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_873">10.15479/AT:ISTA:th_873</a>
  apa: Nikitenko, A. (2017). <i>Discrete Morse theory for random complexes </i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_873">https://doi.org/10.15479/AT:ISTA:th_873</a>
  chicago: Nikitenko, Anton. “Discrete Morse Theory for Random Complexes .” Institute
    of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_873">https://doi.org/10.15479/AT:ISTA:th_873</a>.
  ieee: A. Nikitenko, “Discrete Morse theory for random complexes ,” Institute of
    Science and Technology Austria, 2017.
  ista: Nikitenko A. 2017. Discrete Morse theory for random complexes . Institute
    of Science and Technology Austria.
  mla: Nikitenko, Anton. <i>Discrete Morse Theory for Random Complexes </i>. Institute
    of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_873">10.15479/AT:ISTA:th_873</a>.
  short: A. Nikitenko, Discrete Morse Theory for Random Complexes , Institute of Science
    and Technology Austria, 2017.
corr_author: '1'
date_created: 2019-04-09T15:04:32Z
date_published: 2017-10-27T00:00:00Z
date_updated: 2026-04-08T14:19:31Z
day: '27'
ddc:
- '514'
- '516'
- '519'
degree_awarded: PhD
department:
- _id: HeEd
doi: 10.15479/AT:ISTA:th_873
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month: '10'
oa: 1
oa_version: Published Version
page: '86'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
pubrep_id: '873'
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  - id: '718'
    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: 'Discrete Morse theory for random complexes '
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  short: CC BY (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '839'
abstract:
- lang: eng
  text: 'This thesis describes a brittle fracture simulation method for visual effects
    applications. Building upon a symmetric Galerkin boundary element method, we first
    compute stress intensity factors following the theory of linear elastic fracture
    mechanics. We then use these stress intensities to simulate the motion of a propagating
    crack front at a significantly higher resolution than the overall deformation
    of the breaking object. Allowing for spatial variations of the material''s toughness
    during crack propagation produces visually realistic, highly-detailed fracture
    surfaces. Furthermore, we introduce approximations for stress intensities and
    crack opening displacements, resulting in both practical speed-up and theoretically
    superior runtime complexity compared to previous methods. While we choose a quasi-static
    approach to fracture mechanics, ignoring dynamic deformations, we also couple
    our fracture simulation framework to a standard rigid-body dynamics solver, enabling
    visual effects artists to simulate both large scale motion, as well as fracturing
    due to collision forces in a combined system. As fractures inside of an object
    grow, their geometry must be represented both in the coarse boundary element mesh,
    as well as at the desired fine output resolution. Using a boundary element method,
    we avoid complicated volumetric meshing operations. Instead we describe a simple
    set of surface meshing operations that allow us to progressively add cracks to
    the mesh of an object and still re-use all previously computed entries of the
    linear boundary element system matrix. On the high resolution level, we opt for
    an implicit surface representation. We then describe how to capture fracture surfaces
    during crack propagation, as well as separate the individual fragments resulting
    from the fracture process, based on this implicit representation. We show results
    obtained with our method, either solving the full boundary element system in every
    time step, or alternatively using our fast approximations. These results demonstrate
    that both of these methods perform well in basic test cases and produce realistic
    fracture surfaces. Furthermore we show that our fast approximations substantially
    out-perform the standard approach in more demanding scenarios. Finally, these
    two methods naturally combine, using the full solution while the problem size
    is manageably small and switching to the fast approximations later on. The resulting
    hybrid method gives the user a direct way to choose between speed and accuracy
    of the simulation. '
acknowledgement: "ERC H2020 programme (grant agreement no. 638176)\r\nFirst of all,
  let me thank my committee members, especially my supervisor, Chris\r\nWojtan, for
  supporting me throughout my PhD. Obviously, none of this work would\r\nhave been
  possible without you.\r\nFurthermore, Thank You to all the people who have contributed
  to this work in various\r\nways, in particular Martin Schanz and his group for providing
  and supporting the\r\nHyENA boundary element library, as well as Eder Miguel and
  Morten Bojsen-Hansen\r\nfor (repeatedly) proof reading and providing valuable suggestions
  during the writing\r\nof this thesis.\r\nI would also like to thank Bernd Bickel,
  and all the members – past and present – of his\r\nand Chris’ research groups at
  IST Austria for always providing honest and insightful\r\nfeedback throughout many
  joint group meetings, as well as Christopher Batty, Eitan\r\nGrinspun, and Fang
  Da for many insights into boundary element methods during our\r\ncollaboration.\r\nAs
  only virtual objects have been harmed in the process of creating this work, I would\r\nlike
  to acknowledge the Stanford scanning repository for providing the “Bunny” and\r\n“Armadillo”
  models, the AIM@SHAPE repository for “Pierre’s hand, watertight”, and\r\nS. Gainsbourg
  for the “Column” via Archive3D.net. Sorry for breaking these models\r\nin many different
  ways.\r\n"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: David
  full_name: Hahn, David
  id: 357A6A66-F248-11E8-B48F-1D18A9856A87
  last_name: Hahn
citation:
  ama: Hahn D. Brittle fracture simulation with boundary elements for computer graphics.
    2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_855">10.15479/AT:ISTA:th_855</a>
  apa: Hahn, D. (2017). <i>Brittle fracture simulation with boundary elements for
    computer graphics</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_855">https://doi.org/10.15479/AT:ISTA:th_855</a>
  chicago: Hahn, David. “Brittle Fracture Simulation with Boundary Elements for Computer
    Graphics.” Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_855">https://doi.org/10.15479/AT:ISTA:th_855</a>.
  ieee: D. Hahn, “Brittle fracture simulation with boundary elements for computer
    graphics,” Institute of Science and Technology Austria, 2017.
  ista: Hahn D. 2017. Brittle fracture simulation with boundary elements for computer
    graphics. Institute of Science and Technology Austria.
  mla: Hahn, David. <i>Brittle Fracture Simulation with Boundary Elements for Computer
    Graphics</i>. Institute of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_855">10.15479/AT:ISTA:th_855</a>.
  short: D. Hahn, Brittle Fracture Simulation with Boundary Elements for Computer
    Graphics, Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:47Z
date_published: 2017-08-14T00:00:00Z
date_updated: 2026-04-08T14:20:16Z
day: '14'
ddc:
- '004'
- '005'
- '006'
- '531'
- '621'
degree_awarded: PhD
department:
- _id: ChWo
doi: 10.15479/AT:ISTA:th_855
ec_funded: 1
file:
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language:
- iso: eng
license: https://creativecommons.org/licenses/by-sa/4.0/
month: '08'
oa: 1
oa_version: Published Version
page: '124'
project:
- _id: 2533E772-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '638176'
  name: 'Big Splash: Efficient Simulation of Natural Phenomena at Extremely Large
    Scales'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6809'
pubrep_id: '855'
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    status: public
status: public
supervisor:
- first_name: Christopher J
  full_name: Wojtan, Christopher J
  id: 3C61F1D2-F248-11E8-B48F-1D18A9856A87
  last_name: Wojtan
  orcid: 0000-0001-6646-5546
title: Brittle fracture simulation with boundary elements for computer graphics
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type: dissertation
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...
---
OA_place: publisher
_id: '202'
abstract:
- lang: eng
  text: 'Restriction-modification (RM) represents the simplest and possibly the most
    widespread mechanism of self/non-self discrimination in nature. In order to provide
    bacteria with immunity against bacteriophages and other parasitic genetic elements,
    RM systems rely on a balance between two enzymes: the restriction enzyme, which
    cleaves non-self DNA at specific restriction sites, and the modification enzyme,
    which tags the host’s DNA as self and thus protects it from cleavage. In this
    thesis, I use population and single-cell level experiments in combination with
    mathematical modeling to study different aspects of the interplay between RM systems,
    bacteria and bacteriophages. First, I analyze how mutations in phage restriction
    sites affect the probability of phage escape – an inherently stochastic process,
    during which phages accidently get modified instead of restricted. Next, I use
    single-cell experiments to show that RM systems can, with a low probability, attack
    the genome of their bacterial host and that this primitive form of autoimmunity
    leads to a tradeoff between the evolutionary cost and benefit of RM systems. Finally,
    I investigate the nature of interactions between bacteria, RM systems and temperate
    bacteriophages to find that, as a consequence of phage escape and its impact on
    population dynamics, RM systems can promote acquisition of symbiotic bacteriophages,
    rather than limit it. The results presented here uncover new fundamental biological
    properties of RM systems and highlight their importance in the ecology and evolution
    of bacteria, bacteriophages and their interactions.'
acknowledgement: "During my PhD studies, I received help from many people, all of
  which unfortunately cannot be listed here. I thank them deeply and hope that I never
  made them regret their kindness.\r\nI would like to express my deepest gratitude
  to Călin Guet, who went far beyond his responsibilities as an advisor and was to
  me also a great mentor and a friend. Călin never questioned my potential or lacked
  compassion and I cannot thank him enough for cultivating in me an independent scientist.
  I was amazed by his ability to recognize the most fascinating scientific problems
  in objects of study that others would find mundane. I hope I adopted at least a
  fraction of this ability.\r\nI will be forever grateful to Bruce Levin for all his
  support and especially for giving me the best possible example of how one can practice
  excellent science with humor and style. Working with Bruce was a true privilege.\r\nI
  thank Jonathan Bollback and Gašper Tkačik for serving in my PhD committee and the
  Austrian Academy of Science for funding my PhD research via the DOC fellowship.\r\nI
  thank all our lab members: Tobias Bergmiller for his guidance, especially in the
  first years of my research, and for being a good friend throughout; Remy Chait for
  staying in the lab at unreasonable hours and for the good laughs at bad jokes we
  shared; Anna Staron for supportively listening to my whines whenever I had to run
  a gel; Magdalena Steinrück for her pioneering work in the lab; Kathrin Tomasek for
  keeping the entropic forces in check and for her FACS virtuosity; Isabella Tomanek
  for always being nice to me, no matter how much bench space I took from her.\r\nI
  thank all my collaborators: Reiko Okura and Yuichi Wakamoto for performing and analyzing
  the microfluidic experiments; Long Qian and Edo Kussell for their bioinformatics
  analysis; Dominik Refardt for the λ kan phage; Moritz for his help with the mathematical
  modeling. I thank Fabienne Jesse for her tireless editorial work on all our manuscripts.\r\nFinally,
  I would like to thank my family and especially my wife Edita, who sacrificed a lot
  so that I can pursue my goals and dreams.\r\n"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Maros
  full_name: Pleska, Maros
  id: 4569785E-F248-11E8-B48F-1D18A9856A87
  last_name: Pleska
  orcid: 0000-0001-7460-7479
citation:
  ama: Pleska M. Biology of restriction-modification systems at the single-cell and
    population level. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_916">10.15479/AT:ISTA:th_916</a>
  apa: Pleska, M. (2017). <i>Biology of restriction-modification systems at the single-cell
    and population level</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_916">https://doi.org/10.15479/AT:ISTA:th_916</a>
  chicago: Pleska, Maros. “Biology of Restriction-Modification Systems at the Single-Cell
    and Population Level.” Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_916">https://doi.org/10.15479/AT:ISTA:th_916</a>.
  ieee: M. Pleska, “Biology of restriction-modification systems at the single-cell
    and population level,” Institute of Science and Technology Austria, 2017.
  ista: Pleska M. 2017. Biology of restriction-modification systems at the single-cell
    and population level. Institute of Science and Technology Austria.
  mla: Pleska, Maros. <i>Biology of Restriction-Modification Systems at the Single-Cell
    and Population Level</i>. Institute of Science and Technology Austria, 2017, doi:<a
    href="https://doi.org/10.15479/AT:ISTA:th_916">10.15479/AT:ISTA:th_916</a>.
  short: M. Pleska, Biology of Restriction-Modification Systems at the Single-Cell
    and Population Level, Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:45:10Z
date_published: 2017-10-01T00:00:00Z
date_updated: 2026-04-08T14:19:44Z
day: '01'
ddc:
- '576'
- '579'
degree_awarded: PhD
department:
- _id: CaGu
doi: 10.15479/AT:ISTA:th_916
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has_accepted_license: '1'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '126'
project:
- _id: 251D65D8-B435-11E9-9278-68D0E5697425
  grant_number: '24210'
  name: Effects of Stochasticity on the Function of Restriction-Modi cation Systems
    at the Single-Cell Level
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '7711'
pubrep_id: '916'
related_material:
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  - id: '561'
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    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Calin C
  full_name: Guet, Calin C
  id: 47F8433E-F248-11E8-B48F-1D18A9856A87
  last_name: Guet
  orcid: 0000-0001-6220-2052
title: Biology of restriction-modification systems at the single-cell and population
  level
tmp:
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  short: CC BY (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '938'
abstract:
- lang: eng
  text: The thesis encompasses several topics of plant cell biology which were studied
    in the model plant Arabidopsis thaliana. Chapter 1 concerns the plant hormone
    auxin and its polar transport through cells and tissues. The highly controlled,
    directional transport of auxin is facilitated by plasma membrane-localized transporters.
    Transporters from the PIN family direct auxin transport due to their polarized
    localizations at cell membranes. Substantial effort has been put into research
    on cellular trafficking of PIN proteins, which is thought to underlie their polar
    distribution. I participated in a forward genetic screen aimed at identifying
    novel regulators of PIN polarity. The screen yielded several genes which may be
    involved in PIN polarity regulation or participate in polar auxin transport by
    other means. Chapter 2 focuses on the endomembrane system, with particular attention
    to clathrin-mediated endocytosis. The project started with identification of several
    proteins that interact with clathrin light chains. Among them, I focused on two
    putative homologues of auxilin, which in non-plant systems is an endocytotic factor
    known for uncoating clathrin-coated vesicles in the final step of endocytosis.
    The body of my work consisted of an in-depth characterization of transgenic A.
    thaliana lines overexpressing these putative auxilins in an inducible manner.
    Overexpression of these proteins leads to an inhibition of endocytosis, as documented
    by imaging of cargoes and clathrin-related endocytic machinery. An extension of
    this work is an investigation into a concept of homeostatic regulation acting
    between distinct transport processes in the endomembrane system. With auxilin
    overexpressing lines, where endocytosis is blocked specifically, I made observations
    on the mutual relationship between two opposite trafficking processes of secretion
    and endocytosis. In Chapter 3, I analyze cortical microtubule arrays and their
    relationship to auxin signaling and polarized growth in elongating cells. In plants,
    microtubules are organized into arrays just below the plasma membrane, and it
    is thought that their function is to guide membrane-docked cellulose synthase
    complexes. These, in turn, influence cell wall structure and cell shape by directed
    deposition of cellulose fibres. In elongating cells, cortical microtubule arrays
    are able to reorient in relation to long cell axis, and these reorientations have
    been linked to cell growth and to signaling of growth-regulating factors such
    as auxin or light. In this chapter, I am addressing the causal relationship between
    microtubule array reorientation, growth, and auxin signaling. I arrive at a model
    where array reorientation is not guided by auxin directly, but instead is only
    controlled by growth, which, in turn, is regulated by auxin.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Maciek
  full_name: Adamowski, Maciek
  id: 45F536D2-F248-11E8-B48F-1D18A9856A87
  last_name: Adamowski
  orcid: 0000-0001-6463-5257
citation:
  ama: Adamowski M. Investigations into cell polarity and trafficking in the plant
    model Arabidopsis thaliana . 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_842">10.15479/AT:ISTA:th_842</a>
  apa: Adamowski, M. (2017). <i>Investigations into cell polarity and trafficking
    in the plant model Arabidopsis thaliana </i>. Institute of Science and Technology
    Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_842">https://doi.org/10.15479/AT:ISTA:th_842</a>
  chicago: Adamowski, Maciek. “Investigations into Cell Polarity and Trafficking in
    the Plant Model Arabidopsis Thaliana .” Institute of Science and Technology Austria,
    2017. <a href="https://doi.org/10.15479/AT:ISTA:th_842">https://doi.org/10.15479/AT:ISTA:th_842</a>.
  ieee: M. Adamowski, “Investigations into cell polarity and trafficking in the plant
    model Arabidopsis thaliana ,” Institute of Science and Technology Austria, 2017.
  ista: Adamowski M. 2017. Investigations into cell polarity and trafficking in the
    plant model Arabidopsis thaliana . Institute of Science and Technology Austria.
  mla: Adamowski, Maciek. <i>Investigations into Cell Polarity and Trafficking in
    the Plant Model Arabidopsis Thaliana </i>. Institute of Science and Technology
    Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_842">10.15479/AT:ISTA:th_842</a>.
  short: M. Adamowski, Investigations into Cell Polarity and Trafficking in the Plant
    Model Arabidopsis Thaliana , Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:49:18Z
date_published: 2017-06-02T00:00:00Z
date_updated: 2026-04-08T14:20:45Z
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supervisor:
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  full_name: Friml, Jiří
  id: 4159519E-F248-11E8-B48F-1D18A9856A87
  last_name: Friml
  orcid: 0000-0002-8302-7596
title: 'Investigations into cell polarity and trafficking in the plant model Arabidopsis
  thaliana '
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
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...
---
OA_place: publisher
_id: '818'
abstract:
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  text: 'Antibiotics have diverse effects on bacteria, including massive changes in
    bacterial gene expression. Whereas the gene expression changes under many antibiotics
    have been measured, the temporal organization of these responses and their dependence
    on the bacterial growth rate are unclear. As described in Chapter 1, we quantified
    the temporal gene expression changes in the bacterium Escherichia coli in response
    to the sudden exposure to antibiotics using a fluorescent reporter library and
    a robotic system. Our data show temporally structured gene expression responses,
    with response times for individual genes ranging from tens of minutes to several
    hours. We observed that many stress response genes were activated in response
    to antibiotics. As certain stress responses cross-protect bacteria from other
    stressors, we then asked whether cellular responses to antibiotics have a similar
    protective role in Chapter 2. Indeed, we found that the trimethoprim-induced acid
    stress response protects bacteria from subsequent acid stress. We combined microfluidics
    with time-lapse imaging to monitor survival, intracellular pH, and acid stress
    response in single cells. This approach revealed that the variable expression
    of the acid resistance operon gadBC strongly correlates with single-cell survival
    time. Cells with higher gadBC expression following trimethoprim maintain higher
    intracellular pH and survive the acid stress longer. Overall, we provide a way
    to identify single-cell cross-protection between antibiotics and environmental
    stressors from temporal gene expression data, and show how antibiotics can increase
    bacterial fitness in changing environments. While gene expression changes to antibiotics
    show a clear temporal structure at the population-level, it is unclear whether
    this clear temporal order is followed by every single cell. Using dual-reporter
    strains described in Chapter 3, we measured gene expression dynamics of promoter
    pairs in the same cells using microfluidics and microscopy. Chapter 4 shows that
    the oxidative stress response and the DNA stress response showed little timing
    variability and a clear temporal order under the antibiotic nitrofurantoin. In
    contrast, the acid stress response under trimethoprim ran independently from all
    other activated response programs including the DNA stress response, which showed
    particularly high timing variability in this stress condition. In summary, this
    approach provides insight into the temporal organization of gene expression programs
    at the single-cell level and suggests dependencies between response programs and
    the underlying variability-introducing mechanisms. Altogether, this work advances
    our understanding of the diverse effects that antibiotics have on bacteria. These
    results were obtained by taking into account gene expression dynamics, which allowed
    us to identify general principles, molecular mechanisms, and dependencies between
    genes. Our findings may have implications for infectious disease treatments, and
    microbial communities in the human body and in nature. '
acknowledgement: 'First of all, I would like to express great gratitude to my PhD
  supervisor Tobias Bollenbach. Through his open and trusting attitude I had the freedom
  to explore different scientific directions during this project, and follow the research
  lines of my interest. I am thankful for constructive and often extensive discussions
  and his support and commitment during the different stages of my PhD. I want to
  thank my committee members, Călin Guet, Terry Hwa and Nassos Typas for their interest
  and their valuable input to this project. Special thanks to Nassos for career guidance,
  and for accepting me in his lab. A big thank you goes to the past, present and affiliated
  members of the Bollenbach group: Guillaume Chevereau, Marjon de Vos, Marta Lukačišinová,
  Veronika Bierbaum, Qi Qin, Marcin Zagórski, Martin Lukačišin, Andreas Angermayr,
  Bor Kavčič, Julia Tischler, Dilay Ayhan, Jaroslav Ferenc, and Georg Rieckh. I enjoyed
  working and discussing with you very much and I will miss our lengthy group meetings,
  our inspiring journal clubs, and our common lunches. Special thanks to Bor for great
  mental and professional support during the hard months of thesis writing, and to
  Marta for very creative times during the beginning of our PhDs. May the ‘Bacterial
  Survival Guide’ decorate the walls of IST forever! A great thanks to my friend and
  collaborator Georg Rieckh for his enthusiasm and for getting so involved in these
  projects, for his endurance and for his company throughout the years. Thanks to
  the FriSBi crowd at IST Austria for interesting meetings and discussions. In particular
  I want to thank Magdalena Steinrück, and Anna Andersson for inspiring exchange,
  and enjoyable time together. Thanks to everybody who contributed to the cover for
  Cell Systems: The constructive input from Tobias Bollenbach, Bor Kavčič, Georg Rieckh,
  Marta Lukačišinová, and Sebastian Nozzi, and the professional implementation by
  the graphic designer Martina Markus from the University of Cologne. Thanks to all
  my office mates in the first floor Bertalanffy building throughout the years: for
  ensuring a pleasant working atmosphere, and for your company! In general, I want
  to thank all the people that make IST such a great environment, with the many possibilities
  to shape our own social and research environment. I want to thank my family for
  all kind of practical support during the years, and my second family in Argentina
  for their enthusiasm. Thanks to my brother Bernhard and my sister Martina for being
  great siblings, and to Helena and Valentin for the joy you brought to my life. My
  deep gratitude goes to Sebastian Nozzi, for constant support, patience, love and
  for believing in me. '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Karin
  full_name: Mitosch, Karin
  id: 39B66846-F248-11E8-B48F-1D18A9856A87
  last_name: Mitosch
citation:
  ama: Mitosch K. Timing, variability and cross-protection in bacteria – insights
    from dynamic gene expression responses to antibiotics. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_862">10.15479/AT:ISTA:th_862</a>
  apa: Mitosch, K. (2017). <i>Timing, variability and cross-protection in bacteria
    – insights from dynamic gene expression responses to antibiotics</i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_862">https://doi.org/10.15479/AT:ISTA:th_862</a>
  chicago: Mitosch, Karin. “Timing, Variability and Cross-Protection in Bacteria –
    Insights from Dynamic Gene Expression Responses to Antibiotics.” Institute of
    Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_862">https://doi.org/10.15479/AT:ISTA:th_862</a>.
  ieee: K. Mitosch, “Timing, variability and cross-protection in bacteria – insights
    from dynamic gene expression responses to antibiotics,” Institute of Science and
    Technology Austria, 2017.
  ista: Mitosch K. 2017. Timing, variability and cross-protection in bacteria – insights
    from dynamic gene expression responses to antibiotics. Institute of Science and
    Technology Austria.
  mla: Mitosch, Karin. <i>Timing, Variability and Cross-Protection in Bacteria – Insights
    from Dynamic Gene Expression Responses to Antibiotics</i>. Institute of Science
    and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_862">10.15479/AT:ISTA:th_862</a>.
  short: K. Mitosch, Timing, Variability and Cross-Protection in Bacteria – Insights
    from Dynamic Gene Expression Responses to Antibiotics, Institute of Science and
    Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:40Z
date_published: 2017-09-27T00:00:00Z
date_updated: 2026-04-08T14:21:57Z
day: '27'
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- '579'
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  full_name: Bollenbach, Mark Tobias
  id: 3E6DB97A-F248-11E8-B48F-1D18A9856A87
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  orcid: 0000-0003-4398-476X
title: Timing, variability and cross-protection in bacteria – insights from dynamic
  gene expression responses to antibiotics
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abstract:
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  text: "This dissertation focuses on algorithmic aspects of program verification,
    and presents modeling and complexity advances on several problems related to the\r\nstatic
    analysis of programs, the stateless model checking of concurrent programs, and
    the competitive analysis of real-time scheduling algorithms.\r\nOur contributions
    can be broadly grouped into five categories.\r\n\r\nOur first contribution is
    a set of new algorithms and data structures for the quantitative and data-flow
    analysis of programs, based on the graph-theoretic notion of treewidth.\r\nIt
    has been observed that the control-flow graphs of typical programs have special
    structure, and are characterized as graphs of small treewidth.\r\nWe utilize this
    structural property to provide faster algorithms for the quantitative and data-flow
    analysis of recursive and concurrent programs.\r\nIn most cases we make an algebraic
    treatment of the considered problem,\r\nwhere several interesting analyses, such
    as the reachability, shortest path, and certain kind of data-flow analysis problems
    follow as special cases. \r\nWe exploit the constant-treewidth property to obtain
    algorithmic improvements for on-demand versions of the problems, \r\nand provide
    data structures with various tradeoffs between the resources spent in the preprocessing
    and querying phase.\r\nWe also improve on the algorithmic complexity of quantitative
    problems outside the algebraic path framework,\r\nnamely of the minimum mean-payoff,
    minimum ratio, and minimum initial credit for energy problems.\r\n\r\n\r\nOur
    second contribution is a set of algorithms for Dyck reachability with applications
    to data-dependence analysis and alias analysis.\r\nIn particular, we develop an
    optimal algorithm for Dyck reachability on bidirected graphs, which are ubiquitous
    in context-insensitive, field-sensitive points-to analysis.\r\nAdditionally, we
    develop an efficient algorithm for context-sensitive data-dependence analysis
    via Dyck reachability,\r\nwhere the task is to obtain analysis summaries of library
    code in the presence of callbacks.\r\nOur algorithm preprocesses libraries in
    almost linear time, after which the contribution of the library in the complexity
    of the client analysis is (i)~linear in the number of call sites and (ii)~only
    logarithmic in the size of the whole library, as opposed to linear in the size
    of the whole library.\r\nFinally, we prove that Dyck reachability is Boolean Matrix
    Multiplication-hard in general, and the hardness also holds for graphs of constant
    treewidth.\r\nThis hardness result strongly indicates that there exist no combinatorial
    algorithms for Dyck reachability with truly subcubic complexity.\r\n\r\n\r\nOur
    third contribution is the formalization and algorithmic treatment of the Quantitative
    Interprocedural Analysis framework.\r\nIn this framework, the transitions of a
    recursive program are annotated as good, bad or neutral, and receive a weight
    which measures\r\nthe magnitude of their respective effect.\r\nThe Quantitative
    Interprocedural Analysis problem asks to determine whether there exists an infinite
    run of the program where the long-run ratio of the bad weights over the good weights
    is above a given threshold.\r\nWe illustrate how several quantitative problems
    related to static analysis of recursive programs can be instantiated in this framework,\r\nand
    present some case studies to this direction.\r\n\r\n\r\nOur fourth contribution
    is a new dynamic partial-order reduction for the stateless model checking of concurrent
    programs. Traditional approaches rely on the standard Mazurkiewicz equivalence
    between  traces, by means of partitioning the trace space into equivalence classes,
    and attempting to explore a few representatives from each class.\r\nWe present
    a new dynamic partial-order reduction method  called the Data-centric Partial
    Order Reduction (DC-DPOR).\r\nOur algorithm is based on a new equivalence between
    traces, called the observation equivalence.\r\nDC-DPOR explores a coarser partitioning
    of the trace space than any exploration method based on the standard Mazurkiewicz
    equivalence.\r\nDepending on the program, the new partitioning can be even exponentially
    coarser.\r\nAdditionally, DC-DPOR spends only polynomial time in each explored
    class.\r\n\r\n\r\nOur fifth contribution is the use of automata and game-theoretic
    verification techniques in the competitive analysis and synthesis of real-time
    scheduling algorithms for firm-deadline tasks.\r\nOn the analysis side, we leverage
    automata on infinite words to compute the competitive ratio of real-time schedulers
    subject to various environmental constraints.\r\nOn the synthesis side, we introduce
    a new instance of two-player mean-payoff partial-information games, and show\r\nhow
    the synthesis of an optimal real-time scheduler can be reduced to computing winning
    strategies in this new type of games."
acknowledgement: "First, I am thankful to my advisor, Krishnendu Chatterjee, for offering
  me the opportunity to\r\nmaterialize my scientific curiosity in a remarkably wide
  range of interesting topics, as well as for his constant availability and continuous
  support throughout my doctoral studies. I have had the privilege of collaborating
  with, discussing and getting inspired by all members of my committee: Thomas A.
  Henzinger, Ulrich Schmid and Martin A. Nowak. The role of the above four people
  has been very instrumental both to the research carried out for this dissertation,
  and to the researcher I evolved to in the process.\r\nI have greatly enjoyed my
  numerous brainstorming sessions with Rasmus Ibsen-Jensen, many\r\nof which led to
  results on low-treewidth graphs presented here.  I thank Alex Kößler for our\r\ndiscussions
  on modeling and analyzing real-time scheduling algorithms, Yaron Velner for our\r\ncollaboration
  on the Quantitative Interprocedural Analysis framework, and Nishant Sinha for our
  initial discussions on partial order reduction techniques in stateless model checking.
  I also thank Jan Otop, Ben Adlam, Bernhard Kragl and Josef Tkadlec for our fruitful
  collaborations on\r\ntopics outside the scope of this dissertation, as well as the
  interns Prateesh Goyal, Amir Kafshdar Goharshady, Samarth Mishra, Bhavya Choudhary
  and Marek Chalupa, with whom I have shared my excitement on various research topics.
  Together with my collaborators, I thank officemates and members of the Chatterjee
  and Henzinger groups throughout the years, Thorsten Tarrach, Ventsi Chonev, Roopsha
  Samanta, Przemek Daca, Mirco Giacobbe, Tanja Petrov, Ashutosh\r\nGupta,  Arjun Radhakrishna,
  \ Petr Novontý,  Christian Hilbe,  Jakob Ruess,  Martin Chmelik,\r\nCezara Dragoi,
  Johannes Reiter, Andrey Kupriyanov, Guy Avni, Sasha Rubin, Jessica Davies, Hongfei
  Fu, Thomas Ferrère, Pavol Cerný, Ali Sezgin, Jan Kretínský, Sergiy Bogomolov, Hui\r\nKong,
  Benjamin Aminof, Duc-Hiep Chu, and Damien Zufferey.  Besides collaborations and
  office spaces, with many of the above people I have been fortunate to share numerous
  whiteboard\r\ndiscussions, as well as memorable long walks and amicable meals accompanied
  by stimulating\r\nconversations. I am highly indebted to Elisabeth Hacker for her
  continuous assistance in matters\r\nthat often exceeded her official duties, and
  who made my integration in Austria a smooth process."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Andreas
  full_name: Pavlogiannis, Andreas
  id: 49704004-F248-11E8-B48F-1D18A9856A87
  last_name: Pavlogiannis
  orcid: 0000-0002-8943-0722
citation:
  ama: Pavlogiannis A. Algorithmic advances in program analysis and their applications.
    2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_854">10.15479/AT:ISTA:th_854</a>
  apa: Pavlogiannis, A. (2017). <i>Algorithmic advances in program analysis and their
    applications</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_854">https://doi.org/10.15479/AT:ISTA:th_854</a>
  chicago: Pavlogiannis, Andreas. “Algorithmic Advances in Program Analysis and Their
    Applications.” Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_854">https://doi.org/10.15479/AT:ISTA:th_854</a>.
  ieee: A. Pavlogiannis, “Algorithmic advances in program analysis and their applications,”
    Institute of Science and Technology Austria, 2017.
  ista: Pavlogiannis A. 2017. Algorithmic advances in program analysis and their applications.
    Institute of Science and Technology Austria.
  mla: Pavlogiannis, Andreas. <i>Algorithmic Advances in Program Analysis and Their
    Applications</i>. Institute of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_854">10.15479/AT:ISTA:th_854</a>.
  short: A. Pavlogiannis, Algorithmic Advances in Program Analysis and Their Applications,
    Institute of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:41Z
date_published: 2017-08-09T00:00:00Z
date_updated: 2026-04-08T14:22:17Z
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  - id: '1437'
    relation: part_of_dissertation
    status: public
  - id: '1071'
    relation: part_of_dissertation
    status: public
  - id: '1607'
    relation: part_of_dissertation
    status: public
  - id: '1714'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Krishnendu
  full_name: Chatterjee, Krishnendu
  id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87
  last_name: Chatterjee
  orcid: 0000-0002-4561-241X
title: Algorithmic advances in program analysis and their applications
tmp:
  image: /image/cc_by_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nd/4.0/legalcode
  name: Creative Commons Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0)
  short: CC BY-ND (4.0)
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2017'
...
---
OA_place: publisher
_id: '1155'
abstract:
- lang: eng
  text: This dissertation concerns the automatic verification of probabilistic systems
    and programs with arrays by statistical and logical methods. Although statistical
    and logical methods are different in nature, we show that they can be successfully
    combined for system analysis. In the first part of the dissertation we present
    a new statistical algorithm for the verification of probabilistic systems with
    respect to unbounded properties, including linear temporal logic. Our algorithm
    often performs faster than the previous approaches, and at the same time requires
    less information about the system. In addition, our method can be generalized
    to unbounded quantitative properties such as mean-payoff bounds. In the second
    part, we introduce two techniques for comparing probabilistic systems. Probabilistic
    systems are typically compared using the notion of equivalence, which requires
    the systems to have the equal probability of all behaviors. However, this notion
    is often too strict, since probabilities are typically only empirically estimated,
    and any imprecision may break the relation between processes. On the one hand,
    we propose to replace the Boolean notion of equivalence by a quantitative distance
    of similarity. For this purpose, we introduce a statistical framework for estimating
    distances between Markov chains based on their simulation runs, and we investigate
    which distances can be approximated in our framework. On the other hand, we propose
    to compare systems with respect to a new qualitative logic, which expresses that
    behaviors occur with probability one or a positive probability. This qualitative
    analysis is robust with respect to modeling errors and applicable to many domains.
    In the last part, we present a new quantifier-free logic for integer arrays, which
    allows us to express counting. Counting properties are prevalent in array-manipulating
    programs, however they cannot be expressed in the quantified fragments of the
    theory of arrays. We present a decision procedure for our logic, and provide several
    complexity results.
acknowledgement: ' First of all, I want to thank my advisor, prof. Thomas A. Henzinger,
  for his guidance during my PhD program. I am grateful for the freedom I was given
  to pursue my research interests, and his continuous support. Working with prof.
  Henzinger was a truly inspiring experience and taught me what it means to be a scientist.
  I want to express my gratitude to my collaborators: Nikola Beneš, Krishnendu Chatterjee,
  Martin Chmelík, Ashutosh Gupta, Willibald Krenn, Jan Kˇretínský, Dejan Nickovic,
  Andrey Kupriyanov, and Tatjana Petrov. I have learned a great deal from my collaborators,
  and without their help this thesis would not be possible. In addition, I want to
  thank the members of my thesis committee: Dirk Beyer, Dejan Nickovic, and Georg
  Weissenbacher for their advice and reviewing this dissertation. I would especially
  like to acknowledge the late Helmut Veith, who was a member of my committee. I will
  remember Helmut for his kindness, enthusiasm, and wit, as well as for being an inspiring
  scientist. Finally, I would like to thank my colleagues for making my stay at IST
  such a pleasant experience: Guy Avni, Sergiy Bogomolov, Ventsislav Chonev, Rasmus
  Ibsen-Jensen, Mirco Giacobbe, Bernhard Kragl, Hui Kong, Petr Novotný, Jan Otop,
  Andreas Pavlogiannis, Tantjana Petrov, Arjun Radhakrishna, Jakob Ruess, Thorsten
  Tarrach, as well as other members of groups Henzinger and Chatterjee. '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Przemyslaw
  full_name: Daca, Przemyslaw
  id: 49351290-F248-11E8-B48F-1D18A9856A87
  last_name: Daca
citation:
  ama: Daca P. Statistical and logical methods for property checking. 2017. doi:<a
    href="https://doi.org/10.15479/AT:ISTA:TH_730">10.15479/AT:ISTA:TH_730</a>
  apa: Daca, P. (2017). <i>Statistical and logical methods for property checking</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:TH_730">https://doi.org/10.15479/AT:ISTA:TH_730</a>
  chicago: Daca, Przemyslaw. “Statistical and Logical Methods for Property Checking.”
    Institute of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:TH_730">https://doi.org/10.15479/AT:ISTA:TH_730</a>.
  ieee: P. Daca, “Statistical and logical methods for property checking,” Institute
    of Science and Technology Austria, 2017.
  ista: Daca P. 2017. Statistical and logical methods for property checking. Institute
    of Science and Technology Austria.
  mla: Daca, Przemyslaw. <i>Statistical and Logical Methods for Property Checking</i>.
    Institute of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_730">10.15479/AT:ISTA:TH_730</a>.
  short: P. Daca, Statistical and Logical Methods for Property Checking, Institute
    of Science and Technology Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:50:27Z
date_published: 2017-01-02T00:00:00Z
date_updated: 2026-04-15T10:02:13Z
day: '02'
ddc:
- '004'
- '005'
degree_awarded: PhD
department:
- _id: ToHe
doi: 10.15479/AT:ISTA:TH_730
ec_funded: 1
file:
- access_level: open_access
  checksum: 1406a681cb737508234fde34766be2c2
  content_type: application/pdf
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  date_created: 2018-12-12T10:11:26Z
  date_updated: 2020-07-14T12:44:34Z
  file_id: '4880'
  file_name: IST-2017-730-v1+1_Statistical_and_Logical_Methods_for_Property_Checking.pdf
  file_size: 1028586
  relation: main_file
file_date_updated: 2020-07-14T12:44:34Z
has_accepted_license: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: '163'
project:
- _id: 25EE3708-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '267989'
  name: Quantitative Reactive Modeling
- _id: 25F42A32-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z211
  name: Formal methods for the design and analysis of complex systems
- _id: 25832EC2-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: S 11407_N23
  name: Rigorous Systems Engineering
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6203'
pubrep_id: '730'
related_material:
  record:
  - id: '2063'
    relation: part_of_dissertation
    status: public
  - id: '1093'
    relation: part_of_dissertation
    status: public
  - id: '1391'
    relation: part_of_dissertation
    status: public
  - id: '1234'
    relation: part_of_dissertation
    status: public
  - id: '1230'
    relation: part_of_dissertation
    status: public
  - id: '1501'
    relation: part_of_dissertation
    status: public
  - id: '1502'
    relation: part_of_dissertation
    status: public
  - id: '2167'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Thomas A
  full_name: Henzinger, Thomas A
  id: 40876CD8-F248-11E8-B48F-1D18A9856A87
  last_name: Henzinger
  orcid: 0000−0002−2985−7724
title: Statistical and logical methods for property checking
type: dissertation
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2017'
...
---
OA_place: publisher
_id: '819'
abstract:
- lang: eng
  text: 'Contagious diseases must transmit from infectious to susceptible hosts in
    order to reproduce. Whilst vectored pathogens can rely on intermediaries to find
    new hosts for them, many infectious pathogens require close contact or direct
    interaction between hosts for transmission. Hence, this means that conspecifics
    are often the main source of infection for most animals and so, in theory, animals
    should avoid conspecifics to reduce their risk of infection. Of course, in reality
    animals must interact with one another, as a bare minimum, to mate. However, being
    social provides many additional benefits and group living has become a taxonomically
    diverse and widespread trait. How then do social animals overcome the issue of
    increased disease? Over the last few decades, the social insects (ants, termites
    and some bees and wasps) have become a model system for studying disease in social
    animals. On paper, a social insect colony should be particularly susceptible to
    disease, given that they often contain thousands of potential hosts that are closely
    related and frequently interact, as well as exhibiting stable environmental conditions
    that encourage microbial growth. Yet, disease outbreaks appear to be rare and
    attempts to eradicate pest species using pathogens have failed time and again.
    Evolutionary biologists investigating this observation have discovered that the
    reduced disease susceptibility in social insects is, in part, due to collectively
    performed disease defences of the workers. These defences act like a “social immune
    system” for the colony, resulting in a per capita decrease in disease, termed
    social immunity. Our understanding of social immunity, and its importance in relation
    to the immunological defences of each insect, continues to grow, but there remain
    many open questions. In this thesis I have studied disease defence in garden ants.
    In the first data chapter, I use the invasive garden ant, Lasius neglectus, to
    investigate how colonies mitigate lethal infections and prevent them from spreading
    systemically. I find that ants have evolved ‘destructive disinfection’ – a behaviour
    that uses endogenously produced acidic poison to kill diseased brood and to prevent
    the pathogen from replicating. In the second experimental chapter, I continue
    to study the use of poison in invasive garden ant colonies, finding that it is
    sprayed prophylactically within the nest. However, this spraying has negative
    effects on developing pupae when they have had their cocoons artificially removed.
    Hence, I suggest that acidic nest sanitation may be maintaining larval cocoon
    spinning in this species. In the next experimental chapter, I investigated how
    colony founding black garden ant queens (Lasius niger) prevent disease when a
    co-foundress dies. I show that ant queens prophylactically perform undertaking
    behaviours, similar to those performed by the workers in mature nests. When a
    co-foundress was infected, these undertaking behaviours improved the survival
    of the healthy queen. In the final data chapter, I explored how immunocompetence
    (measured as antifungal activity) changes as incipient black garden ant colonies
    grow and mature, from the solitary queen phase to colonies with several hundred
    workers. Queen and worker antifungal activity varied throughout this time period,
    but despite social immunity, did not decrease as colonies matured. In addition
    to the above data chapters, this thesis includes two co-authored reviews. In the
    first, we examine the state of the art in the field of social immunity and how
    it might develop in the future. In the second, we identify several challenges
    and open questions in the study of disease defence in animals. We highlight how
    social insects offer a unique model to tackle some of these problems, as disease
    defence can be studied from the cell to the society. '
acknowledgement: "ERC FP7 programme (grant agreement no. 240371)\r\nI have been supremely
  spoilt to work in a lab with such good resources and I must thank the wonderful
  Cremer group technicians, Anna, Barbara, Eva and Florian, for all of their help
  and keeping the lab up and running. You guys will probably be the most missed once
  I realise just how much work you have been saving me! For the same reason, I must
  say a big Dzi ę kuj ę Ci to Wonder Woman Wanda, for her tireless efforts feeding
  my colonies and cranking out thousands of petri dishes and sugar tubes. Again, you
  will be sorely missed now that I will have to take this task on myself. Of course,
  I will be eternally indebted to Prof. Sylvia Cremer for taking me under her wing
  and being a constant source of guidance and inspiration. You have given me the perfect
  balance of independence and supervision. I cannot thank you enough for creating
  such a great working environment and allowing me the freedom to follow my own research
  questions. I have had so many exceptional opportunities – attending and presenting
  at conferences all over the world, inviting me to write the ARE with you, going
  to workshops in Panama and Switzerland, and even organising our own PhD course –
  that I often think I must have had the best PhD in the world. You have taught me
  so much and made me a scientist. I sincerely hope we get the chance to work together
  again in the future. Thank you for everything. I must also thank my PhD Committee,
  Daria Siekhaus and Jacobus “Koos” Boomsma, for being very supportive throughout
  the duration of my PhD. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Christopher
  full_name: Pull, Christopher
  id: 3C7F4840-F248-11E8-B48F-1D18A9856A87
  last_name: Pull
  orcid: 0000-0003-1122-3982
citation:
  ama: Pull C. Disease defence in garden ants. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_861">10.15479/AT:ISTA:th_861</a>
  apa: Pull, C. (2017). <i>Disease defence in garden ants</i>. Institute of Science
    and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_861">https://doi.org/10.15479/AT:ISTA:th_861</a>
  chicago: Pull, Christopher. “Disease Defence in Garden Ants.” Institute of Science
    and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_861">https://doi.org/10.15479/AT:ISTA:th_861</a>.
  ieee: C. Pull, “Disease defence in garden ants,” Institute of Science and Technology
    Austria, 2017.
  ista: Pull C. 2017. Disease defence in garden ants. Institute of Science and Technology
    Austria.
  mla: Pull, Christopher. <i>Disease Defence in Garden Ants</i>. Institute of Science
    and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_861">10.15479/AT:ISTA:th_861</a>.
  short: C. Pull, Disease Defence in Garden Ants, Institute of Science and Technology
    Austria, 2017.
corr_author: '1'
date_created: 2018-12-11T11:48:40Z
date_published: 2017-09-26T00:00:00Z
date_updated: 2026-04-16T10:07:02Z
day: '26'
ddc:
- '576'
- '577'
- '578'
- '579'
- '590'
- '592'
degree_awarded: PhD
department:
- _id: SyCr
doi: 10.15479/AT:ISTA:th_861
file:
- access_level: closed
  checksum: 4993cdd5382295758ecc3ecbd2a9aaff
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: dernst
  date_created: 2019-04-05T07:53:04Z
  date_updated: 2020-07-14T12:48:09Z
  file_id: '6199'
  file_name: 2017_Thesis_Pull.docx
  file_size: 18580400
  relation: source_file
- access_level: open_access
  checksum: ee2e3ebb5b53c154c866f5b052b25153
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  creator: dernst
  date_created: 2019-04-05T07:53:04Z
  date_updated: 2020-07-14T12:48:09Z
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  file_name: 2017_Thesis_Pull.pdf
  file_size: 14400681
  relation: main_file
file_date_updated: 2020-07-14T12:48:09Z
has_accepted_license: '1'
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: '122'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6830'
pubrep_id: '861'
related_material:
  record:
  - id: '806'
    relation: part_of_dissertation
    status: public
  - id: '616'
    relation: part_of_dissertation
    status: public
  - id: '732'
    relation: part_of_dissertation
    status: public
  - id: '734'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Sylvia M
  full_name: Cremer, Sylvia M
  id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87
  last_name: Cremer
  orcid: 0000-0002-2193-3868
title: Disease defence in garden ants
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: '2017'
...
---
OA_place: publisher
_id: '961'
abstract:
- lang: eng
  text: Cell-cell  contact  formation  constitutes  the  first  step  in  the  emergence  of  multicellularity  in
    evolution, thereby  allowing  the  differentiation  of  specialized  cell  types.  In  metazoan
    development, cell-cell contact formation is thought to influence cell fate specification,
    and cell   fate   specification   has   been   implicated   in   cell-cell  contact
    formation.   However, remarkably little is yet known about whether and how the
    interaction and feedback between cell-cell contact formation and cell fate specification
    affect development. Here we identify a positive  feedback  loop  between  cell-cell  contact  duration,  morphogen  signaling  and
    mesendoderm  cell  fate  specification  during  zebrafish  gastrulation.  We  show  that  long
    lasting cell-cell contacts enhance the competence of prechordal plate (ppl) progenitor
    cells to  respond  to  Nodal  signaling,  required  for  proper  ppl  cell  fate  specification.  We  further
    show  that  Nodal  signalling  romotes  ppl  cell-cell  contact  duration,  thereby  generating  an
    effective  positive  feedback  loop  between  ppl  cell-cell  contact  duration  and  cell  fate
    specification. Finally, by using a combination of theoretical modeling and experimentation,
    we  show  that  this  feedback  loop  determines  whether  anterior  axial  mesendoderm  cells
    become  ppl  progenitors  or,  instead,  turn  into  endoderm  progenitors.  Our  findings  reveal
    that  the  gene  regulatory  networks  leading  to  cell  fate  diversification  within  the  developing
    embryo  are  controlled  by  the  interdependent  activities  of  cell-cell  signaling  and  contact
    formation.
acknowledgement: "Many people accompanied me during this trip: I would not have reached
  my destination nor \r\nenjoyed the travelling without them. First of all, thanks
  to CP. Thanks for making me part of \r\nyour team, always full of diverse, interesting
  and incredibly competent people and thanks for \r\nall  the  good  science  I  witnessed
  \ and  participated  in.  It  has  been  a \r\nblast,  an  incredibly \r\nexciting
  \ one!  Thanks  to  JLo,  for  teaching  me  how  to  master  my  pipettes  and
  \ showing  me \r\nthat science is a lot of fun. Many, many thanks to Gabby for teaching
  me basically everything \r\nabout  zebrafish  and  being  always  there  to  advice,
  \ sugge\r\nst,  support...and  play  fussball! \r\nThank you to Julien, for the
  critical eye on things, Pedro, for all the invaluable feedback and \r\nthe amazing
  kicker matches, and Keisuke, for showing me the light, and to the three of them
  \r\ntogether  for  all  the  good  laughs  we\r\nhad.  My  start  in  Vienna  would
  \ have  been  a  lot  more \r\ndifficult  without  you  guys.  Also  it  would  not
  \ have  been  possible  without  Elena  and  Inês: \r\nthanks  for  helping  setting
  \ up  this  lab  and  for  the  dinners  in  Gugging.  Thanks  to  Martin,  for
  \r\nhelping  me  understand \r\nthe  physics  behind  biology.  Thanks  to  Philipp,
  \ for  the  interest  and \r\nadvice, and to Michael, for the Viennise take on things.
  Thanks to Julia, for putting up with \r\nbeing our technician and becoming a friend
  in the process. And now to the newest members \r\nof th\r\ne lab. Thanks to Daniel
  for the enthusiasm and the neverending energy and for all your \r\nhelp over the
  years: thank you! To Jana, for showing me that one doesn’t give up, no matter \r\nwhat.
  \ To  Shayan,  for  being  such  a  motivated  student.  To  Matt,  for  helping
  \ out\r\nwith  coding \r\nand for finding punk solutions to data analysis problems.
  Thanks to all the members of the \r\nlab, Verena, Hitoshi, Silvia, Conny, Karla,
  Nicoletta, Zoltan, Peng, Benoit, Roland, Yuuta and \r\nFeyza,  for  the  wonderful
  \ atmosphere  in  the  lab.  Many  than\r\nks  to  Koni  and  Deborah:  doing \r\nexperiments
  would have been much more difficult without your help. Special thanks to Katjia
  \r\nfor  setting  up  an  amazing  imaging  facility  and  for  building  the  best
  \ team,  Robert,  Nasser, \r\nAnna and Doreen: thank you for putting up w\r\nith
  all the late sortings and for helping with all \r\nthe technical problems. Thanks
  to Eva, Verena and Matthias for keeping the fish happy. Big \r\nthanks to Harald
  Janovjak for being a present and helpful committee member over the years \r\nand
  \ to  Patrick  Lemaire  f\r\nor  the  helpful  insight  and  extremely  interesting
  \ discussion  we  had \r\nabout  the  project.  Also,  this  journey  would  not
  \ have  been  the  same  without  all  the  friends \r\nthat I met in Dresden and
  then in Vienna: Daniele, Claire, Kuba, Steffi, Harold, Dejan, Irene, \r\nFab\r\nienne,
  Hande, Tiago, Marianne, Jon, Srdjan, Branca, Uli, Murat, Alex, Conny, Christoph,
  \r\nCaro, Simone, Barbara, Felipe, Dama, Jose, Hubert and many others that filled
  my days with \r\nfun and support. A special thank to my family, always close even
  if they are \r\nkilometers away. \r\nGrazie  ai  miei  fratelli,  Nunzio  e  William,
  \ e  alla  mia  mamma,  per  essermi  sempre  vicini  pur \r\nvivendo a chilometri
  di distanza. And, last but not least, thanks to Moritz, for putting up with \r\nthe
  crazy life of a scientist, the living apart for\r\nso long, never knowing when things
  are going \r\nto happen. Thanks for being a great partner and my number one fan!"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Vanessa
  full_name: Barone, Vanessa
  id: 419EECCC-F248-11E8-B48F-1D18A9856A87
  last_name: Barone
  orcid: 0000-0003-2676-3367
citation:
  ama: 'Barone V. Cell adhesion and cell fate: An effective feedback loop during zebrafish
    gastrulation. 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_825">10.15479/AT:ISTA:th_825</a>'
  apa: 'Barone, V. (2017). <i>Cell adhesion and cell fate: An effective feedback loop
    during zebrafish gastrulation</i>. Institute of Science and Technology Austria.
    <a href="https://doi.org/10.15479/AT:ISTA:th_825">https://doi.org/10.15479/AT:ISTA:th_825</a>'
  chicago: 'Barone, Vanessa. “Cell Adhesion and Cell Fate: An Effective Feedback Loop
    during Zebrafish Gastrulation.” Institute of Science and Technology Austria, 2017.
    <a href="https://doi.org/10.15479/AT:ISTA:th_825">https://doi.org/10.15479/AT:ISTA:th_825</a>.'
  ieee: 'V. Barone, “Cell adhesion and cell fate: An effective feedback loop during
    zebrafish gastrulation,” Institute of Science and Technology Austria, 2017.'
  ista: 'Barone V. 2017. Cell adhesion and cell fate: An effective feedback loop during
    zebrafish gastrulation. Institute of Science and Technology Austria.'
  mla: 'Barone, Vanessa. <i>Cell Adhesion and Cell Fate: An Effective Feedback Loop
    during Zebrafish Gastrulation</i>. Institute of Science and Technology Austria,
    2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_825">10.15479/AT:ISTA:th_825</a>.'
  short: 'V. Barone, Cell Adhesion and Cell Fate: An Effective Feedback Loop during
    Zebrafish Gastrulation, Institute of Science and Technology Austria, 2017.'
corr_author: '1'
date_created: 2018-12-11T11:49:25Z
date_published: 2017-03-01T00:00:00Z
date_updated: 2026-04-16T10:07:32Z
day: '01'
ddc:
- '570'
- '590'
degree_awarded: PhD
department:
- _id: CaHe
doi: 10.15479/AT:ISTA:th_825
file:
- access_level: closed
  checksum: 242f88c87f2cf267bf05049fa26a687b
  content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
  creator: dernst
  date_created: 2019-04-05T08:36:52Z
  date_updated: 2020-07-14T12:48:16Z
  file_id: '6205'
  file_name: 2017_Barone_thesis_final.docx
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language:
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month: '03'
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oa_version: Published Version
page: '109'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6444'
pubrep_id: '825'
related_material:
  record:
  - id: '735'
    relation: part_of_dissertation
    status: public
  - id: '1100'
    relation: part_of_dissertation
    status: public
  - id: '1537'
    relation: part_of_dissertation
    status: public
  - id: '1912'
    relation: part_of_dissertation
    status: public
  - id: '3246'
    relation: part_of_dissertation
    status: public
  - id: '2926'
    relation: part_of_dissertation
    status: public
  - id: '676'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Carl-Philipp J
  full_name: Heisenberg, Carl-Philipp J
  id: 39427864-F248-11E8-B48F-1D18A9856A87
  last_name: Heisenberg
  orcid: 0000-0002-0912-4566
title: 'Cell adhesion and cell fate: An effective feedback loop during zebrafish gastrulation'
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: '2017'
...
---
OA_place: publisher
_id: '1397'
abstract:
- lang: eng
  text: 'We study partially observable Markov decision processes (POMDPs) with objectives
    used in verification and artificial intelligence. The qualitative analysis problem
    given a POMDP and an objective asks whether there is a strategy (policy) to ensure
    that the objective is satisfied almost surely (with probability 1), resp. with
    positive probability (with probability greater than 0). For POMDPs with limit-average
    payoff, where a reward value in the interval [0,1] is associated to every transition,
    and the payoff of an infinite path is the long-run average of the rewards, we
    consider two types of path constraints: (i) a quantitative limit-average constraint
    defines the set of paths where the payoff is at least a given threshold L1 = 1.
    Our main results for qualitative limit-average constraint under almost-sure winning
    are as follows: (i) the problem of deciding the existence of a finite-memory controller
    is EXPTIME-complete; and (ii) the problem of deciding the existence of an infinite-memory
    controller is undecidable. For quantitative limit-average constraints we show
    that the problem of deciding the existence of a finite-memory controller is undecidable.
    We present a prototype implementation of our EXPTIME algorithm. For POMDPs with
    w-regular conditions specified as parity objectives, while the qualitative analysis
    problems are known to be undecidable even for very special case of parity objectives,
    we establish decidability (with optimal complexity) of the qualitative analysis
    problems for POMDPs with parity objectives under finite-memory strategies. We
    establish optimal (exponential) memory bounds and EXPTIME-completeness of the
    qualitative analysis problems under finite-memory strategies for POMDPs with parity
    objectives. Based on our theoretical algorithms we also present a practical approach,
    where we design heuristics to deal with the exponential complexity, and have applied
    our implementation on a number of well-known POMDP examples for robotics applications.
    For POMDPs with a set of target states and an integer cost associated with every
    transition, we study the optimization objective that asks to minimize the expected
    total cost of reaching a state in the target set, while ensuring that the target
    set is reached almost surely. We show that for general integer costs approximating
    the optimal cost is undecidable. For positive costs, our results are as follows:
    (i) we establish matching lower and upper bounds for the optimal cost, both double
    and exponential in the POMDP state space size; (ii) we show that the problem of
    approximating the optimal cost is decidable and present approximation algorithms
    that extend existing algorithms for POMDPs with finite-horizon objectives. We
    show experimentally that it performs well in many examples of interest. We study
    more deeply the problem of almost-sure reachability, where  given a set of target
    states, the question is to decide whether there is a strategy to ensure that the
    target set is reached almost surely. While in general the problem EXPTIME-complete,
    in many practical cases strategies with a small amount of memory suffice. Moreover,
    the existing solution to the problem is explicit, which first requires to construct
    explicitly an exponential reduction to a belief-support MDP. We first study the
    existence of observation-stationary strategies, which is NP-complete, and then
    small-memory strategies. We present a symbolic algorithm by an efficient encoding
    to SAT and using a SAT solver for the problem. We report experimental results
    demonstrating the scalability of our symbolic (SAT-based) approach. Decentralized
    POMDPs (DEC-POMDPs) extend POMDPs to a multi-agent setting, where several agents
    operate in an uncertain environment independently to achieve a joint objective.
    In this work we consider Goal DEC-POMDPs, where given a set of target states,
    the objective is to ensure that the target set is reached with minimal cost. We
    consider the indefinite-horizon (infinite-horizon with either discounted-sum,
    or undiscounted-sum, where absorbing goal states have zero-cost) problem. We present
    a new and novel method to solve the problem that extends methods for finite-horizon
    DEC-POMDPs and the real-time dynamic programming approach for POMDPs. We present
    experimental results on several examples, and show that our approach presents
    promising results. In the end we present a short summary of a few other results
    related to verification of MDPs and POMDPs.'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Martin
  full_name: Chmelik, Martin
  id: 3624234E-F248-11E8-B48F-1D18A9856A87
  last_name: Chmelik
citation:
  ama: Chmelik M. Algorithms for partially observable markov decision processes. 2016.
  apa: Chmelik, M. (2016). <i>Algorithms for partially observable markov decision
    processes</i>. Institute of Science and Technology Austria.
  chicago: Chmelik, Martin. “Algorithms for Partially Observable Markov Decision Processes.”
    Institute of Science and Technology Austria, 2016.
  ieee: M. Chmelik, “Algorithms for partially observable markov decision processes,”
    Institute of Science and Technology Austria, 2016.
  ista: Chmelik M. 2016. Algorithms for partially observable markov decision processes.
    Institute of Science and Technology Austria.
  mla: Chmelik, Martin. <i>Algorithms for Partially Observable Markov Decision Processes</i>.
    Institute of Science and Technology Austria, 2016.
  short: M. Chmelik, Algorithms for Partially Observable Markov Decision Processes,
    Institute of Science and Technology Austria, 2016.
corr_author: '1'
date_created: 2018-12-11T11:51:47Z
date_published: 2016-02-01T00:00:00Z
date_updated: 2026-04-08T14:23:19Z
day: '01'
degree_awarded: PhD
department:
- _id: KrCh
language:
- iso: eng
month: '02'
oa_version: None
page: '232'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5810'
status: public
supervisor:
- first_name: Krishnendu
  full_name: Chatterjee, Krishnendu
  id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87
  last_name: Chatterjee
  orcid: 0000-0002-4561-241X
title: Algorithms for partially observable markov decision processes
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2016'
...
---
OA_place: publisher
_id: '1129'
abstract:
- lang: eng
  text: "Directed cell migration is a hallmark feature, present in almost all multi-cellular\r\norganisms.
    Despite its importance, basic questions regarding force transduction\r\nor directional
    sensing are still heavily investigated. Directed migration of cells\r\nguided
    by immobilized guidance cues - haptotaxis - occurs in key-processes,\r\nsuch as
    embryonic development and immunity (Middleton et al., 1997; Nguyen\r\net al.,
    2000; Thiery, 1984; Weber et al., 2013). Immobilized guidance cues\r\ncomprise
    adhesive ligands, such as collagen and fibronectin (Barczyk et al.,\r\n2009),
    or chemokines - the main guidance cues for migratory leukocytes\r\n(Middleton
    et al., 1997; Weber et al., 2013). While adhesive ligands serve as\r\nattachment
    sites guiding cell migration (Carter, 1965), chemokines instruct\r\nhaptotactic
    migration by inducing adhesion to adhesive ligands and directional\r\nguidance
    (Rot and Andrian, 2004; Schumann et al., 2010). Quantitative analysis\r\nof the
    cellular response to immobilized guidance cues requires in vitro assays\r\nthat
    foster cell migration, offer accurate control of the immobilized cues on a\r\nsubcellular
    scale and in the ideal case closely reproduce in vivo conditions. The\r\nexploration
    of haptotactic cell migration through design and employment of such\r\nassays
    represents the main focus of this work.\r\nDendritic cells (DCs) are leukocytes,
    which after encountering danger\r\nsignals such as pathogens in peripheral organs
    instruct naïve T-cells and\r\nconsequently the adaptive immune response in the
    lymph node (Mellman and\r\nSteinman, 2001). To reach the lymph node from the periphery,
    DCs follow\r\nhaptotactic gradients of the chemokine CCL21 towards lymphatic vessels\r\n(Weber
    et al., 2013). Questions about how DCs interpret haptotactic CCL21\r\ngradients
    have not yet been addressed. The main reason for this is the lack of\r\nan assay
    that offers diverse haptotactic environments, hence allowing the study\r\nof DC
    migration as a response to different signals of immobilized guidance cue.\r\nIn
    this work, we developed an in vitro assay that enables us to\r\nquantitatively
    assess DC haptotaxis, by combining precisely controllable\r\nchemokine photo-patterning
    with physically confining migration conditions. With this tool at hand, we studied
    the influence of CCL21 gradient properties and\r\nconcentration on DC haptotaxis.
    We found that haptotactic gradient sensing\r\ndepends on the absolute CCL21 concentration
    in combination with the local\r\nsteepness of the gradient. Our analysis suggests
    that the directionality of\r\nmigrating DCs is governed by the signal-to-noise
    ratio of CCL21 binding to its\r\nreceptor CCR7. Moreover, the haptotactic CCL21
    gradient formed in vivo\r\nprovides an optimal shape for DCs to recognize haptotactic
    guidance cue.\r\nBy reconstitution of the CCL21 gradient in vitro we were also
    able to\r\nstudy the influence of CCR7 signal termination on DC haptotaxis. To
    this end,\r\nwe used DCs lacking the G-protein coupled receptor kinase GRK6, which
    is\r\nresponsible for CCL21 induced CCR7 receptor phosphorylation and\r\ndesensitization
    (Zidar et al., 2009). We found that CCR7 desensitization by\r\nGRK6 is crucial
    for maintenance of haptotactic CCL21 gradient sensing in vitro\r\nand confirm
    those observations in vivo.\r\nIn the context of the organism, immobilized haptotactic
    guidance cues\r\noften coincide and compete with soluble chemotactic guidance
    cues. During\r\nwound healing, fibroblasts are exposed and influenced by adhesive
    cues and\r\nsoluble factors at the same time (Wu et al., 2012; Wynn, 2008). Similarly,\r\nmigrating
    DCs are exposed to both, soluble chemokines (CCL19 and truncated\r\nCCL21) inducing
    chemotactic behavior as well as the immobilized CCL21. To\r\nquantitatively assess
    these complex coinciding immobilized and soluble\r\nguidance cues, we implemented
    our chemokine photo-patterning technique in a\r\nmicrofluidic system allowing
    for chemotactic gradient generation. To validate\r\nthe assay, we observed DC
    migration in competing CCL19/CCL21\r\nenvironments.\r\nAdhesiveness guided haptotaxis
    has been studied intensively over the\r\nlast century. However, quantitative studies
    leading to conceptual models are\r\nlargely missing, again due to the lack of
    a precisely controllable in vitro assay. A\r\nrequirement for such an in vitro
    assay is that it must prevent any uncontrolled\r\ncell adhesion. This can be accomplished
    by stable passivation of the surface. In\r\naddition, controlled adhesion must
    be sustainable, quantifiable and dose\r\ndependent in order to create homogenous
    gradients. Therefore, we developed a novel covalent photo-patterning technique
    satisfying all these needs. In\r\ncombination with a sustainable poly-vinyl alcohol
    (PVA) surface coating we\r\nwere able to generate gradients of adhesive cue to
    direct cell migration. This\r\napproach allowed us to characterize the haptotactic
    migratory behavior of\r\nzebrafish keratocytes in vitro. Furthermore, defined
    patterns of adhesive cue\r\nallowed us to control for cell shape and growth on
    a subcellular scale."
acknowledged_ssus:
- _id: Bio
- _id: PreCl
- _id: LifeSc
acknowledgement: "First, I would like to thank Michael Sixt for being a great supervisor,
  mentor and\r\nscientist. I highly appreciate his guidance and continued support.
  Furthermore, I\r\nam very grateful that he gave me the exceptional opportunity to
  pursue many\r\nideas of which some managed to be included in this thesis.\r\nI owe
  sincere thanks to the members of my PhD thesis committee, Daria\r\nSiekhaus, Daniel
  Legler and Harald Janovjak. Especially I would like to thank\r\nDaria for her advice
  and encouragement during our regular progress meetings.\r\nI also want to thank
  the team and fellows of the Boehringer Ingelheim Fond\r\n(BIF) PhD Fellowship for
  amazing and inspiring meetings and the BIF for\r\nfinancial support.\r\nImportant
  factors for the success of this thesis were the warm, creative\r\nand helpful atmosphere
  as well as the team spirit of the whole Sixt Lab.\r\nTherefore I would like to thank
  my current and former colleagues Frank Assen,\r\nMarkus Brown, Ingrid de Vries,
  Michelle Duggan, Alexander Eichner, Miroslav\r\nHons, Eva Kiermaier, Aglaja Kopf,
  Alexander Leithner, Christine Moussion, Jan\r\nMüller, Maria Nemethova, Jörg Renkawitz,
  Anne Reversat, Kari Vaahtomeri,\r\nMichele Weber and Stefan Wieser. We had an amazing
  time with many\r\nlegendary evenings and events. Along these lines I want to thank
  the in vitro\r\ncrew of the lab, Jörg, Anne and Alex, for lots of ideas and productive\r\ndiscussions.
  I am sure, some day we will reveal the secret of the ‘splodge’.\r\nI want to thank
  the members of the Heisenberg Lab for a great time and\r\nthrilling kicker matches.
  In this regard I especially want to thank Maurizio\r\n‘Gnocci’ Monti, Gabriel Krens,
  Alex Eichner, Martin Behrndt, Vanessa Barone,Philipp Schmalhorst, Michael Smutny,
  Daniel Capek, Anne Reversat, Eva\r\nKiermaier, Frank Assen and Jan Müller for wonderful
  after-lunch matches.\r\nI would not have been able to analyze the thousands of cell
  trajectories\r\nand probably hundreds of thousands of mouse clicks without the productive\r\ncollaboration
  with Veronika Bierbaum and Tobias Bollenbach. Thanks Vroni for\r\ncountless meetings,
  discussions and graphs and of course for proofreading and\r\nadvice for this thesis.
  For proofreading I also want to thank Evi, Jörg, Jack and\r\nAnne.\r\nI would like
  to acknowledge Matthias Mehling for a very productive\r\ncollaboration and for introducing
  me into the wild world of microfluidics. Jack\r\nMerrin, for countless wafers, PDMS
  coated coverslips and help with anything\r\nmicro-fabrication related. And Maria
  Nemethova for establishing the ‘click’\r\npatterning approach with me. Without her
  it still would be just one of the ideas…\r\nMany thanks to Ekaterina Papusheva,
  Robert Hauschild, Doreen Milius\r\nand Nasser Darwish from the Bioimaging Facility
  as well as the Preclinical and\r\nthe Life Science facilities of IST Austria for
  excellent technical support. At this\r\npoint I especially want to thank Robert
  for countless image analyses and\r\ntechnical ideas. Always interested and creative
  he played an essential role in all\r\nof my projects.\r\nAdditionally I want to
  thank Ingrid and Gabby for welcoming me warmly\r\nwhen I first started at IST, for
  scientific and especially mental support in all\r\nthose years, countless coffee
  sessions and Heurigen evenings. #BioimagingFacility #LifeScienceFacility #PreClinicalFacility"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Jan
  full_name: Schwarz, Jan
  id: 346C1EC6-F248-11E8-B48F-1D18A9856A87
  last_name: Schwarz
citation:
  ama: Schwarz J. Quantitative analysis of haptotactic cell migration. 2016.
  apa: Schwarz, J. (2016). <i>Quantitative analysis of haptotactic cell migration</i>.
    Institute of Science and Technology Austria.
  chicago: Schwarz, Jan. “Quantitative Analysis of Haptotactic Cell Migration.” Institute
    of Science and Technology Austria, 2016.
  ieee: J. Schwarz, “Quantitative analysis of haptotactic cell migration,” Institute
    of Science and Technology Austria, 2016.
  ista: Schwarz J. 2016. Quantitative analysis of haptotactic cell migration. Institute
    of Science and Technology Austria.
  mla: Schwarz, Jan. <i>Quantitative Analysis of Haptotactic Cell Migration</i>. Institute
    of Science and Technology Austria, 2016.
  short: J. Schwarz, Quantitative Analysis of Haptotactic Cell Migration, Institute
    of Science and Technology Austria, 2016.
corr_author: '1'
date_created: 2018-12-11T11:50:18Z
date_published: 2016-07-01T00:00:00Z
date_updated: 2026-04-08T14:28:53Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: MiSi
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has_accepted_license: '1'
language:
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month: '07'
oa: 1
oa_version: Published Version
page: '178'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6231'
status: public
supervisor:
- first_name: Michael K
  full_name: Sixt, Michael K
  id: 41E9FBEA-F248-11E8-B48F-1D18A9856A87
  last_name: Sixt
  orcid: 0000-0002-6620-9179
title: Quantitative analysis of haptotactic cell migration
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2016'
...
