---
_id: '1124'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Maurizio
  full_name: Morri, Maurizio
  id: 4863116E-F248-11E8-B48F-1D18A9856A87
  last_name: Morri
citation:
  ama: Morri M. Optical functionalization of human class A orphan G-protein coupled
    receptors. 2016.
  apa: Morri, M. (2016). <i>Optical functionalization of human class A orphan G-protein
    coupled receptors</i>. Institute of Science and Technology Austria.
  chicago: Morri, Maurizio. “Optical Functionalization of Human Class A Orphan G-Protein
    Coupled Receptors.” Institute of Science and Technology Austria, 2016.
  ieee: M. Morri, “Optical functionalization of human class A orphan G-protein coupled
    receptors,” Institute of Science and Technology Austria, 2016.
  ista: Morri M. 2016. Optical functionalization of human class A orphan G-protein
    coupled receptors. Institute of Science and Technology Austria.
  mla: Morri, Maurizio. <i>Optical Functionalization of Human Class A Orphan G-Protein
    Coupled Receptors</i>. Institute of Science and Technology Austria, 2016.
  short: M. Morri, Optical Functionalization of Human Class A Orphan G-Protein Coupled
    Receptors, Institute of Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:17Z
date_published: 2016-03-01T00:00:00Z
date_updated: 2023-09-07T11:43:03Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: HaJa
file:
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  checksum: b439803ac0827cdddd56562a54e3b53b
  content_type: application/pdf
  creator: dernst
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language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
page: '129'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6236'
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: Optical functionalization of human class A orphan G-protein coupled receptors
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1125'
abstract:
- lang: eng
  text: "Natural environments are never constant but subject to spatial and temporal
    change on\r\nall scales, increasingly so due to human activity. Hence, it is crucial
    to understand the\r\nimpact of environmental variation on evolutionary processes.
    In this thesis, I present\r\nthree topics that share the common theme of environmental
    variation, yet illustrate its\r\neffect from different perspectives.\r\nFirst,
    I show how a temporally fluctuating environment gives rise to second-order\r\nselection
    on a modifier for stress-induced mutagenesis. Without fluctuations, when\r\npopulations
    are adapted to their environment, mutation rates are minimized. I argue\r\nthat
    a stress-induced mutator mechanism may only be maintained if the population is\r\nrepeatedly
    subjected to diverse environmental challenges, and I outline implications of\r\nthe
    presented results to antibiotic treatment strategies.\r\nSecond, I discuss my
    work on the evolution of dispersal. Besides reproducing\r\nknown results about
    the effect of heterogeneous habitats on dispersal, it identifies\r\nspatial changes
    in dispersal type frequencies as a source for selection for increased\r\npropensities
    to disperse. This concept contains effects of relatedness that are known\r\nto
    promote dispersal, and I explain how it identifies other forces selecting for
    dispersal\r\nand puts them on a common scale.\r\nThird, I analyse genetic variances
    of phenotypic traits under multivariate stabilizing\r\nselection. For the case
    of constant environments, I generalize known formulae of\r\nequilibrium variances
    to multiple traits and discuss how the genetic variance of a focal\r\ntrait is
    influenced by selection on background traits. I conclude by presenting ideas and\r\npreliminary
    work aiming at including environmental fluctuations in the form of moving\r\ntrait
    optima into the model."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Sebastian
  full_name: Novak, Sebastian
  id: 461468AE-F248-11E8-B48F-1D18A9856A87
  last_name: Novak
  orcid: 0000-0002-2519-824X
citation:
  ama: Novak S. Evolutionary proccesses in variable emvironments. 2016.
  apa: Novak, S. (2016). <i>Evolutionary proccesses in variable emvironments</i>.
    Institute of Science and Technology Austria.
  chicago: Novak, Sebastian. “Evolutionary Proccesses in Variable Emvironments.” Institute
    of Science and Technology Austria, 2016.
  ieee: S. Novak, “Evolutionary proccesses in variable emvironments,” Institute of
    Science and Technology Austria, 2016.
  ista: Novak S. 2016. Evolutionary proccesses in variable emvironments. Institute
    of Science and Technology Austria.
  mla: Novak, Sebastian. <i>Evolutionary Proccesses in Variable Emvironments</i>.
    Institute of Science and Technology Austria, 2016.
  short: S. Novak, Evolutionary Proccesses in Variable Emvironments, Institute of
    Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:17Z
date_published: 2016-07-01T00:00:00Z
date_updated: 2025-05-28T11:57:05Z
day: '01'
ddc:
- '576'
degree_awarded: PhD
department:
- _id: NiBa
file:
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  creator: dernst
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file_date_updated: 2021-02-22T13:42:47Z
has_accepted_license: '1'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: '124'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6235'
related_material:
  record:
  - id: '2023'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Nicholas H
  full_name: Barton, Nicholas H
  id: 4880FE40-F248-11E8-B48F-1D18A9856A87
  last_name: Barton
  orcid: 0000-0002-8548-5240
title: Evolutionary proccesses in variable emvironments
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1126'
abstract:
- lang: eng
  text: "Traditionally machine learning has been focusing on the problem of solving
    a single\r\ntask in isolation. While being quite well understood, this approach
    disregards an\r\nimportant aspect of human learning: when facing a new problem,
    humans are able to\r\nexploit knowledge acquired from previously learned tasks.
    Intuitively, access to several\r\nproblems simultaneously or sequentially could
    also be advantageous for a machine\r\nlearning system, especially if these tasks
    are closely related. Indeed, results of many\r\nempirical studies have provided
    justification for this intuition. However, theoretical\r\njustifications of this
    idea are rather limited.\r\nThe focus of this thesis is to expand the understanding
    of potential benefits of information\r\ntransfer between several related learning
    problems. We provide theoretical\r\nanalysis for three scenarios of multi-task
    learning - multiple kernel learning, sequential\r\nlearning and active task selection.
    We also provide a PAC-Bayesian perspective on\r\nlifelong learning and investigate
    how the task generation process influences the generalization\r\nguarantees in
    this scenario. In addition, we show how some of the obtained\r\ntheoretical results
    can be used to derive principled multi-task and lifelong learning\r\nalgorithms
    and illustrate their performance on various synthetic and real-world datasets."
acknowledgement: "First and foremost I would like to express my gratitude to my supervisor,
  Christoph\r\nLampert. Thank you for your patience in teaching me all aspects of
  doing research\r\n(including English grammar), for your trust in my capabilities
  and endless support. Thank\r\nyou for granting me freedom in my research and, at
  the same time, having time and\r\nhelping me cope with the consequences whenever
  I needed it. Thank you for creating\r\nan excellent atmosphere in the group, it
  was a great pleasure and honor to be a part of\r\nit. There could not have been
  a better and more inspiring adviser and mentor.\r\nI thank Shai Ben-David for welcoming
  me into his group at the University of Waterloo,\r\nfor inspiring discussions and
  support. It was a great pleasure to work together. I am\r\nalso thankful to Ruth
  Urner for hosting me at the Max-Planck Institute Tübingen, for the\r\nfruitful
  collaboration and for taking care of me during that not-so-sunny month of May.\r\nI
  thank Jan Maas for kindly joining my thesis committee despite the short notice and\r\nproviding
  me with insightful comments.\r\nI would like to thank my colleagues for their support,
  entertaining conversations and\r\nendless table soccer games we shared together:
  Georg, Jan, Amelie and Emilie, Michal\r\nand Alex, Alex K. and Alex Z., Thomas,
  Sameh, Vlad, Mayu, Nathaniel, Silvester, Neel,\r\nCsaba, Vladimir, Morten. Thank
  you, Mabel and Ram, for the wonderful time we spent\r\ntogether. I am thankful to
  Shrinu and Samira for taking care of me during my stay at the\r\nUniversity of Waterloo.
  Special thanks to Viktoriia for her never-ending optimism and for\r\nbeing so inspiring
  and supportive, especially at the beginning of my PhD journey.\r\nThanks to IST
  administration, in particular, Vlad and Elisabeth for shielding me from\r\nmost
  of the bureaucratic paperwork.\r\n\r\nThis dissertation would not have been possible
  without funding from the European\r\nResearch Council under the European Union's
  Seventh Framework Programme\r\n(FP7/2007-2013)/ERC grant agreement no 308036."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Anastasia
  full_name: Pentina, Anastasia
  id: 42E87FC6-F248-11E8-B48F-1D18A9856A87
  last_name: Pentina
citation:
  ama: Pentina A. Theoretical foundations of multi-task lifelong learning. 2016. doi:<a
    href="https://doi.org/10.15479/AT:ISTA:TH_776">10.15479/AT:ISTA:TH_776</a>
  apa: Pentina, A. (2016). <i>Theoretical foundations of multi-task lifelong learning</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:TH_776">https://doi.org/10.15479/AT:ISTA:TH_776</a>
  chicago: Pentina, Anastasia. “Theoretical Foundations of Multi-Task Lifelong Learning.”
    Institute of Science and Technology Austria, 2016. <a href="https://doi.org/10.15479/AT:ISTA:TH_776">https://doi.org/10.15479/AT:ISTA:TH_776</a>.
  ieee: A. Pentina, “Theoretical foundations of multi-task lifelong learning,” Institute
    of Science and Technology Austria, 2016.
  ista: Pentina A. 2016. Theoretical foundations of multi-task lifelong learning.
    Institute of Science and Technology Austria.
  mla: Pentina, Anastasia. <i>Theoretical Foundations of Multi-Task Lifelong Learning</i>.
    Institute of Science and Technology Austria, 2016, doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_776">10.15479/AT:ISTA:TH_776</a>.
  short: A. Pentina, Theoretical Foundations of Multi-Task Lifelong Learning, Institute
    of Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:17Z
date_published: 2016-11-01T00:00:00Z
date_updated: 2023-09-07T11:52:03Z
day: '01'
ddc:
- '006'
degree_awarded: PhD
department:
- _id: ChLa
doi: 10.15479/AT:ISTA:TH_776
ec_funded: 1
file:
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  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:14:07Z
  date_updated: 2018-12-12T10:14:07Z
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file_date_updated: 2018-12-12T10:14:07Z
has_accepted_license: '1'
language:
- iso: eng
month: '11'
oa: 1
oa_version: Published Version
page: '127'
project:
- _id: 2532554C-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '308036'
  name: Lifelong Learning of Visual Scene Understanding
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6234'
pubrep_id: '776'
status: public
supervisor:
- first_name: Christoph
  full_name: Lampert, Christoph
  id: 40C20FD2-F248-11E8-B48F-1D18A9856A87
  last_name: Lampert
  orcid: 0000-0001-8622-7887
title: Theoretical foundations of multi-task lifelong learning
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1128'
abstract:
- lang: eng
  text: "The process of gene expression is central to the modern understanding of
    how cellular systems\r\nfunction. In this process, a special kind of regulatory
    proteins, called transcription factors,\r\nare important to determine how much
    protein is produced from a given gene. As biological\r\ninformation is transmitted
    from transcription factor concentration to mRNA levels to amounts of\r\nprotein,
    various sources of noise arise and pose limits to the fidelity of intracellular
    signaling.\r\nThis thesis concerns itself with several aspects of stochastic gene
    expression: (i) the mathematical\r\ndescription of complex promoters responsible
    for the stochastic production of biomolecules,\r\n(ii) fundamental limits to information
    processing the cell faces due to the interference from multiple\r\nfluctuating
    signals, (iii) how the presence of gene expression noise influences the evolution\r\nof
    regulatory sequences, (iv) and tools for the experimental study of origins and
    consequences\r\nof cell-cell heterogeneity, including an application to bacterial
    stress response systems."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Georg
  full_name: Rieckh, Georg
  id: 34DA8BD6-F248-11E8-B48F-1D18A9856A87
  last_name: Rieckh
citation:
  ama: Rieckh G. Studying the complexities of transcriptional regulation. 2016.
  apa: Rieckh, G. (2016). <i>Studying the complexities of transcriptional regulation</i>.
    Institute of Science and Technology Austria.
  chicago: Rieckh, Georg. “Studying the Complexities of Transcriptional Regulation.”
    Institute of Science and Technology Austria, 2016.
  ieee: G. Rieckh, “Studying the complexities of transcriptional regulation,” Institute
    of Science and Technology Austria, 2016.
  ista: Rieckh G. 2016. Studying the complexities of transcriptional regulation. Institute
    of Science and Technology Austria.
  mla: Rieckh, Georg. <i>Studying the Complexities of Transcriptional Regulation</i>.
    Institute of Science and Technology Austria, 2016.
  short: G. Rieckh, Studying the Complexities of Transcriptional Regulation, Institute
    of Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:18Z
date_published: 2016-08-01T00:00:00Z
date_updated: 2023-09-07T11:44:34Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: GaTk
file:
- access_level: closed
  checksum: ec453918c3bf8e6f460fd1156ef7b493
  content_type: application/pdf
  creator: dernst
  date_created: 2019-08-13T11:46:25Z
  date_updated: 2019-08-13T11:46:25Z
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  creator: dernst
  date_created: 2020-09-21T11:30:40Z
  date_updated: 2020-09-21T11:30:40Z
  file_id: '8542'
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file_date_updated: 2020-09-21T11:30:40Z
has_accepted_license: '1'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
page: '114'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6232'
status: public
supervisor:
- first_name: Gasper
  full_name: Tkacik, Gasper
  id: 3D494DCA-F248-11E8-B48F-1D18A9856A87
  last_name: Tkacik
  orcid: 0000-0002-6699-1455
title: Studying the complexities of transcriptional regulation
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_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.
date_created: 2018-12-11T11:50:18Z
date_published: 2016-07-01T00:00:00Z
date_updated: 2023-09-07T11:54:33Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: MiSi
file:
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  checksum: e3cd6b28f9c5cccb8891855565a2dade
  content_type: application/pdf
  creator: dernst
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  date_updated: 2019-08-13T10:55:35Z
  file_id: '6813'
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  checksum: c3dbe219acf87eed2f46d21d5cca00de
  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T11:43:14Z
  date_updated: 2021-02-22T11:43:14Z
  file_id: '9181'
  file_name: 2016_Thesis_JSchwarz.pdf
  file_size: 8396717
  relation: main_file
  success: 1
file_date_updated: 2021-02-22T11:43:14Z
has_accepted_license: '1'
language:
- iso: eng
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1130'
abstract:
- lang: eng
  text: "In this thesis we present a computer-aided programming approach to concurrency.
    Our approach helps the programmer by automatically fixing concurrency-related
    bugs, i.e. bugs that occur when the program is executed using an aggressive preemptive
    scheduler, but not when using a non-preemptive (cooperative) scheduler. Bugs are
    program behaviours that are incorrect w.r.t. a specification. We consider both
    user-provided explicit specifications in the form of assertion\r\nstatements in
    the code as well as an implicit specification. The implicit specification is inferred
    from the non-preemptive behaviour. Let us consider sequences of calls that the
    program makes to an external interface. The implicit specification requires that
    any such sequence produced under a preemptive scheduler should be included in
    the set of sequences produced under a non-preemptive scheduler. We consider several
    semantics-preserving fixes that go beyond atomic sections typically explored in
    the synchronisation synthesis literature. Our synthesis is able to place locks,
    barriers and wait-signal statements and last, but not least reorder independent
    statements. The latter may be useful if a thread is released to early, e.g., before
    some initialisation is completed. We guarantee that our synthesis does not introduce
    deadlocks and that the synchronisation inserted is optimal w.r.t. a given objective
    function. We dub our solution trace-based synchronisation synthesis and it is
    loosely based on counterexample-guided inductive synthesis (CEGIS). The synthesis
    works by discovering a trace that is incorrect w.r.t. the specification and identifying
    ordering constraints crucial to trigger the specification violation. Synchronisation
    may be placed immediately (greedy approach) or delayed until all incorrect traces
    are found (non-greedy approach). For the non-greedy approach we construct a set
    of global constraints over synchronisation placements. Each model of the global
    constraints set corresponds to a correctness-ensuring synchronisation placement.
    The placement that is optimal w.r.t. the given objective function is chosen as
    the synchronisation solution. We evaluate our approach on a number of realistic
    (albeit simplified) Linux device-driver\r\nbenchmarks. The benchmarks are versions
    of the drivers with known concurrency-related bugs. For the experiments with an
    explicit specification we added assertions that would detect the bugs in the experiments.
    Device drivers lend themselves to implicit specification, where the device and
    the operating system are the external interfaces. Our experiments demonstrate
    that our synthesis method is precise and efficient. We implemented objective functions
    for coarse-grained and fine-grained locking and observed that different synchronisation
    placements are produced for our experiments, favouring e.g. a minimal number of
    synchronisation operations or maximum concurrency."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Thorsten
  full_name: Tarrach, Thorsten
  id: 3D6E8F2C-F248-11E8-B48F-1D18A9856A87
  last_name: Tarrach
  orcid: 0000-0003-4409-8487
citation:
  ama: Tarrach T. Automatic synthesis of synchronisation primitives for concurrent
    programs. 2016. doi:<a href="https://doi.org/10.15479/at:ista:1130">10.15479/at:ista:1130</a>
  apa: Tarrach, T. (2016). <i>Automatic synthesis of synchronisation primitives for
    concurrent programs</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:1130">https://doi.org/10.15479/at:ista:1130</a>
  chicago: Tarrach, Thorsten. “Automatic Synthesis of Synchronisation Primitives for
    Concurrent Programs.” Institute of Science and Technology Austria, 2016. <a href="https://doi.org/10.15479/at:ista:1130">https://doi.org/10.15479/at:ista:1130</a>.
  ieee: T. Tarrach, “Automatic synthesis of synchronisation primitives for concurrent
    programs,” Institute of Science and Technology Austria, 2016.
  ista: Tarrach T. 2016. Automatic synthesis of synchronisation primitives for concurrent
    programs. Institute of Science and Technology Austria.
  mla: Tarrach, Thorsten. <i>Automatic Synthesis of Synchronisation Primitives for
    Concurrent Programs</i>. Institute of Science and Technology Austria, 2016, doi:<a
    href="https://doi.org/10.15479/at:ista:1130">10.15479/at:ista:1130</a>.
  short: T. Tarrach, Automatic Synthesis of Synchronisation Primitives for Concurrent
    Programs, Institute of Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:19Z
date_published: 2016-07-07T00:00:00Z
date_updated: 2023-09-07T11:57:01Z
day: '07'
ddc:
- '000'
degree_awarded: PhD
department:
- _id: ToHe
- _id: GradSch
doi: 10.15479/at:ista:1130
ec_funded: 1
file:
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  file_id: '10296'
  file_name: 2016_Tarrach_Thesispdfa.pdf
  file_size: 1306068
  relation: main_file
file_date_updated: 2021-11-17T13:46:55Z
has_accepted_license: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://thorstent.github.io/theses/phd_thorsten_tarrach.pdf
month: '07'
oa: 1
oa_version: Published Version
page: '151'
project:
- _id: 25EE3708-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '267989'
  name: Quantitative Reactive Modeling
- _id: 25832EC2-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: S 11407_N23
  name: Rigorous Systems Engineering
- _id: 25F42A32-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: Z211
  name: The Wittgenstein Prize
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6230'
related_material:
  record:
  - id: '1729'
    relation: part_of_dissertation
    status: public
  - id: '2218'
    relation: part_of_dissertation
    status: public
  - id: '2445'
    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: Automatic synthesis of synchronisation primitives for concurrent programs
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1131'
abstract:
- lang: eng
  text: "Evolution of gene regulation is important for phenotypic evolution and diversity.
    Sequence-specific binding of regulatory proteins is one of the key regulatory
    mechanisms determining gene expression. Although there has been intense interest
    in evolution of regulatory binding sites in the last decades, a theoretical understanding
    is far from being complete. In this thesis, I aim at a better understanding of
    the evolution of transcriptional regulatory binding sequences by using biophysical
    and population genetic models.\r\nIn the first part of the thesis, I discuss how
    to formulate the evolutionary dynamics of binding se- quences in a single isolated
    binding site and in promoter/enhancer regions. I develop a theoretical framework
    bridging between a thermodynamical model for transcription and a mutation-selection-drift
    model for monomorphic populations. I mainly address the typical evolutionary rates,
    and how they de- pend on biophysical parameters (e.g. binding length and specificity)
    and population genetic parameters (e.g. population size and selection strength).\r\nIn
    the second part of the thesis, I analyse empirical data for a better evolutionary
    and biophysical understanding of sequence-specific binding of bacterial RNA polymerase.
    First, I infer selection on regulatory and non-regulatory binding sites of RNA
    polymerase in the E. coli K12 genome. Second, I infer the chemical potential of
    RNA polymerase, an important but unknown physical parameter defining the threshold
    energy for strong binding. Furthermore, I try to understand the relation between
    the lac promoter sequence diversity and the LacZ activity variation among 20 bacterial
    isolates by constructing a simple but biophysically motivated gene expression
    model. Lastly, I lay out a statistical framework to predict adaptive point mutations
    in de novo promoter evolution in a selection experiment."
acknowledgement: This PhD thesis may not have been completed without the help and
  care I received from some peo- ple during my PhD life. I am especially grateful
  to Tiago Paixao, Gasper Tkacik, Nick Barton, not only for their scientific advices
  but also for their patience and support. I thank Calin Guet and Jonathan Bollback
  for allowing me to “play around” in their labs and get some experience on experimental
  evolution. I thank Magdalena Steinrueck and Fabienne Jesse for collaborating and
  sharing their experimental data with me. I thank Johannes Jaeger for reviewing my
  thesis. I thank all members of Barton group (aka bartonians) for their feedback,
  and all workers of IST Austria for making the best working conditions. Lastly, I
  thank two special women, Nejla Sag ̆lam and Setenay Dog ̆an, for their continuous
  support and encouragement. I truly had a great chance of having right people around
  me.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Murat
  full_name: Tugrul, Murat
  id: 37C323C6-F248-11E8-B48F-1D18A9856A87
  last_name: Tugrul
  orcid: 0000-0002-8523-0758
citation:
  ama: Tugrul M. Evolution of transcriptional regulatory sequences. 2016.
  apa: Tugrul, M. (2016). <i>Evolution of transcriptional regulatory sequences</i>.
    Institute of Science and Technology Austria.
  chicago: Tugrul, Murat. “Evolution of Transcriptional Regulatory Sequences.” Institute
    of Science and Technology Austria, 2016.
  ieee: M. Tugrul, “Evolution of transcriptional regulatory sequences,” Institute
    of Science and Technology Austria, 2016.
  ista: Tugrul M. 2016. Evolution of transcriptional regulatory sequences. Institute
    of Science and Technology Austria.
  mla: Tugrul, Murat. <i>Evolution of Transcriptional Regulatory Sequences</i>. Institute
    of Science and Technology Austria, 2016.
  short: M. Tugrul, Evolution of Transcriptional Regulatory Sequences, Institute of
    Science and Technology Austria, 2016.
date_created: 2018-12-11T11:50:19Z
date_published: 2016-07-01T00:00:00Z
date_updated: 2025-05-28T11:57:04Z
day: '01'
ddc:
- '576'
degree_awarded: PhD
department:
- _id: NiBa
file:
- access_level: closed
  checksum: 66cb61a59943e4fb7447c6a86be5ef51
  content_type: application/pdf
  creator: dernst
  date_created: 2019-08-13T08:53:52Z
  date_updated: 2019-08-13T08:53:52Z
  file_id: '6810'
  file_name: Tugrul_thesis_w_signature_page.pdf
  file_size: 3695257
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- access_level: open_access
  checksum: 293e388d70563760f6b24c3e66283dda
  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T11:45:20Z
  date_updated: 2021-02-22T11:45:20Z
  file_id: '9182'
  file_name: 2016_Tugrul_Thesis.pdf
  file_size: 3880811
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  success: 1
file_date_updated: 2021-02-22T11:45:20Z
has_accepted_license: '1'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: '89'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '6229'
related_material:
  record:
  - id: '5554'
    relation: research_data
    status: public
  - id: '1666'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Nicholas H
  full_name: Barton, Nicholas H
  id: 4880FE40-F248-11E8-B48F-1D18A9856A87
  last_name: Barton
  orcid: 0000-0002-8548-5240
title: Evolution of transcriptional regulatory sequences
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1396'
abstract:
- lang: eng
  text: CA3 pyramidal neurons are thought to pay a key role in memory storage and
    pattern completion by activity-dependent synaptic plasticity between CA3-CA3 recurrent
    excitatory synapses. To examine the induction rules of synaptic plasticity at
    CA3-CA3 synapses, we performed whole-cell patch-clamp recordings in acute hippocampal
    slices from rats (postnatal 21-24 days) at room temperature. Compound excitatory
    postsynaptic potentials (ESPSs) were recorded by tract stimulation in stratum
    oriens in the presence of 10 µM gabazine. High-frequency stimulation (HFS) induced
    N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP). Although
    LTP by HFS did not requier postsynaptic spikes, it was blocked by Na+-channel
    blockers suggesting that local active processes (e.g.) dendritic spikes) may contribute
    to LTP induction without requirement of a somatic action potential (AP). We next
    examined the properties of spike timing-dependent plasticity (STDP) at CA3-CA3
    synapses. Unexpectedly, low-frequency pairing of EPSPs and backpropagated action
    potentialy (bAPs) induced LTP, independent of temporal order. The STDP curve was
    symmetric and broad, with a half-width of ~150 ms. Consistent with these specific
    STDP induction properties, post-presynaptic sequences led to a supralinear summation
    of spine [Ca2+] transients. Furthermore, in autoassociative network models, storage
    and recall was substantially more robust with symmetric than with asymmetric STDP
    rules. In conclusion, we found associative forms of LTP at CA3-CA3 recurrent collateral
    synapses with distinct induction rules. LTP induced by HFS may be associated with
    dendritic spikes. In contrast, low frequency pairing of pre- and postsynaptic
    activity induced LTP only if EPSP-AP were temporally very close. Together, these
    induction mechanisms of synaptiic plasticity may contribute to memory storage
    in the CA3-CA3 microcircuit at different ranges of activity.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Rajiv Kumar
  full_name: Mishra, Rajiv Kumar
  id: 46CB58F2-F248-11E8-B48F-1D18A9856A87
  last_name: Mishra
citation:
  ama: Mishra RK. Synaptic plasticity rules at CA3-CA3 recurrent synapses in hippocampus.
    2016.
  apa: Mishra, R. K. (2016). <i>Synaptic plasticity rules at CA3-CA3 recurrent synapses
    in hippocampus</i>. Institute of Science and Technology Austria.
  chicago: Mishra, Rajiv Kumar. “Synaptic Plasticity Rules at CA3-CA3 Recurrent Synapses
    in Hippocampus.” Institute of Science and Technology Austria, 2016.
  ieee: R. K. Mishra, “Synaptic plasticity rules at CA3-CA3 recurrent synapses in
    hippocampus,” Institute of Science and Technology Austria, 2016.
  ista: Mishra RK. 2016. Synaptic plasticity rules at CA3-CA3 recurrent synapses in
    hippocampus. Institute of Science and Technology Austria.
  mla: Mishra, Rajiv Kumar. <i>Synaptic Plasticity Rules at CA3-CA3 Recurrent Synapses
    in Hippocampus</i>. Institute of Science and Technology Austria, 2016.
  short: R.K. Mishra, Synaptic Plasticity Rules at CA3-CA3 Recurrent Synapses in Hippocampus,
    Institute of Science and Technology Austria, 2016.
date_created: 2018-12-11T11:51:46Z
date_published: 2016-03-01T00:00:00Z
date_updated: 2023-09-07T11:55:26Z
day: '01'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: PeJo
file:
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  checksum: 5a010a838faf040f7064f3cfb802f743
  content_type: application/pdf
  creator: dernst
  date_created: 2019-08-09T12:14:46Z
  date_updated: 2020-07-14T12:44:48Z
  file_id: '6782'
  file_name: Thesis_Mishra_Rajiv (Final).pdf
  file_size: 2407572
  relation: main_file
- access_level: open_access
  checksum: 81b26d9ede92c99f1d8cc6fa1d04cbbb
  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T11:48:44Z
  date_updated: 2021-02-22T11:48:44Z
  file_id: '9183'
  file_name: 2016_RajivMishra_Thesis.pdf
  file_size: 2407572
  relation: main_file
  success: 1
file_date_updated: 2021-02-22T11:48:44Z
has_accepted_license: '1'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
page: '83'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5811'
related_material:
  record:
  - id: '1432'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Peter M
  full_name: Jonas, Peter M
  id: 353C1B58-F248-11E8-B48F-1D18A9856A87
  last_name: Jonas
  orcid: 0000-0001-5001-4804
title: Synaptic plasticity rules at CA3-CA3 recurrent synapses in hippocampus
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_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.
date_created: 2018-12-11T11:51:47Z
date_published: 2016-02-01T00:00:00Z
date_updated: 2023-09-07T11:54:58Z
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1398'
abstract:
- lang: eng
  text: Hybrid zones represent evolutionary laboratories, where recombination brings
    together alleles in combinations which have not previously been tested by selection.
    This provides an excellent opportunity to test the effect of molecular variation
    on fitness, and how this variation is able to spread through populations in a
    natural context. The snapdragon Antirrhinum majus is polymorphic in the wild for
    two loci controlling the distribution of yellow and magenta floral pigments. Where
    the yellow A. m. striatum and the magenta A. m. pseudomajus meet along a valley
    in the Spanish Pyrenees they form a stable hybrid zone Alleles at these loci recombine
    to give striking transgressive variation for flower colour. The sharp transition
    in phenotype over ~1km implies strong selection maintaining the hybrid zone. An
    indirect assay of pollinator visitation in the field found that pollinators forage
    in a positive-frequency dependent manner on Antirrhinum, matching previous data
    on fruit set. Experimental arrays and paternity analysis of wild-pollinated seeds
    demonstrated assortative mating for pigmentation alleles, and that pollinator
    behaviour alone is sufficient to explain this pattern. Selection by pollinators
    should be sufficiently strong to maintain the hybrid zone, although other mechanisms
    may be at work. At a broader scale I examined evolutionary transitions between
    yellow and anthocyanin pigmentation in the tribe Antirrhinae, and found that selection
    has acted strate that pollinators are a major determinant of reproductive success
    and mating patterns in wild Antirrhinum.
acknowledgement: "I am indebted to many people for their support during my PhD, but
  I particularly wish to thank Nick Barton for his guidance and intuition, and for
  encouraging me to take the time to look beyond the immediate topic of my PhD to
  understand the broader context. I am also especially grateful to David Field his
  bottomless patience, invaluable advice on experimental design, analysis and scientific
  writing, and for tireless work on the population surveys and genomic work without
  most of my thesis could not have happened. \r\n\r\nIt has been a pleasure to work
  with the combined strengths of the groups at The John Innes Centre, University of
  Toulouse and IST Austria. Thanks to Enrico Coen and his group for hosting me in
  Norwich in 2011 and especially for setting up the tag experiment. \r\n\r\nI thank
  David Field, Desmond Bradley and Maria Clara Melo-Hurtado for organising field collections,
  as well as Monique Burrus and Christophe Andalo and a large number of volunteers
  for their e ff orts helping with the field work. Furthermore I thank Coline Jaworski
  for providing seeds and for her input into the design of the experimental arrays,
  and Matthew Couchman for maintaining the database of. \r\n\r\nIn addition to those
  mentioned above, I am grateful to Melinda Pickup, Spencer Barrett, and four anonymous
  reviewers for their insightful comments on sections of this manuscript. I also thank
  Jana Porsche for her e ff orts in tracking down the more obscure references for
  chapter 5, and Jon Bollback for his advice about the analysis. \r\n\r\nI am indebted
  to Jon Ågren for his patience whilst I finished this thesis, and to Sylvia Cremer
  and Magnus Nordborg for taking the time to read and evaluate the thesis given a
  shorter deadline than was fair. \r\n\r\nA very positive aspect of my PhD has been
  the supportive atmosphere of IST. In particular, I have come to appreciate the enormous
  support from our group assistants Nicole Hotzy, Julia Asimakis, Christine Ostermann
  and Jerneja Beslagic. I also thank Christian Chaloupka and Stefan Hipfinger for
  their enthusiasm and readiness to help where possible in setting up our greenhouse
  and experiments. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Thomas
  full_name: Ellis, Thomas
  id: 3153D6D4-F248-11E8-B48F-1D18A9856A87
  last_name: Ellis
  orcid: 0000-0002-8511-0254
citation:
  ama: Ellis T. The role of pollinator-mediated selection in the maintenance of a
    flower color polymorphism in an Antirrhinum majus hybrid zone. 2016. doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_526
    ">10.15479/AT:ISTA:TH_526 </a>
  apa: Ellis, T. (2016). <i>The role of pollinator-mediated selection in the maintenance
    of a flower color polymorphism in an Antirrhinum majus hybrid zone</i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:TH_526
    ">https://doi.org/10.15479/AT:ISTA:TH_526 </a>
  chicago: Ellis, Thomas. “The Role of Pollinator-Mediated Selection in the Maintenance
    of a Flower Color Polymorphism in an Antirrhinum Majus Hybrid Zone.” Institute
    of Science and Technology Austria, 2016. <a href="https://doi.org/10.15479/AT:ISTA:TH_526
    ">https://doi.org/10.15479/AT:ISTA:TH_526 </a>.
  ieee: T. Ellis, “The role of pollinator-mediated selection in the maintenance of
    a flower color polymorphism in an Antirrhinum majus hybrid zone,” Institute of
    Science and Technology Austria, 2016.
  ista: Ellis T. 2016. The role of pollinator-mediated selection in the maintenance
    of a flower color polymorphism in an Antirrhinum majus hybrid zone. Institute
    of Science and Technology Austria.
  mla: Ellis, Thomas. <i>The Role of Pollinator-Mediated Selection in the Maintenance
    of a Flower Color Polymorphism in an Antirrhinum Majus Hybrid Zone</i>. Institute
    of Science and Technology Austria, 2016, doi:<a href="https://doi.org/10.15479/AT:ISTA:TH_526
    ">10.15479/AT:ISTA:TH_526 </a>.
  short: T. Ellis, The Role of Pollinator-Mediated Selection in the Maintenance of
    a Flower Color Polymorphism in an Antirrhinum Majus Hybrid Zone, Institute of
    Science and Technology Austria, 2016.
date_created: 2018-12-11T11:51:47Z
date_published: 2016-02-18T00:00:00Z
date_updated: 2024-02-21T13:51:39Z
day: '18'
ddc:
- '576'
degree_awarded: PhD
department:
- _id: NiBa
doi: '10.15479/AT:ISTA:TH_526 '
file:
- access_level: open_access
  checksum: a89b17ff27cf92c9a15f6b3d46bd7e53
  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:14:51Z
  date_updated: 2020-07-14T12:44:48Z
  file_id: '5106'
  file_name: IST-2016-526-v1+1_Ellis_signed_thesis.pdf
  file_size: 11928241
  relation: main_file
file_date_updated: 2020-07-14T12:44:48Z
has_accepted_license: '1'
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
page: '130'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5809'
pubrep_id: '526'
related_material:
  record:
  - id: '5553'
    relation: popular_science
    status: public
  - id: '5551'
    relation: popular_science
    status: public
  - id: '5552'
    relation: popular_science
    status: public
status: public
supervisor:
- first_name: Nicholas H
  full_name: Barton, Nicholas H
  id: 4880FE40-F248-11E8-B48F-1D18A9856A87
  last_name: Barton
  orcid: 0000-0002-8548-5240
title: The role of pollinator-mediated selection in the maintenance of a flower color
  polymorphism in an Antirrhinum majus hybrid zone
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2016'
...
---
_id: '1399'
abstract:
- lang: eng
  text: This thesis is concerned with the computation and approximation of intrinsic
    volumes. Given a smooth body M and a certain digital approximation of it, we develop
    algorithms to approximate various intrinsic volumes of M using only measurements
    taken from its digital approximations. The crucial idea behind our novel algorithms
    is to link the recent theory of persistent homology to the theory of intrinsic
    volumes via the Crofton formula from integral geometry and, in particular, via
    Euler characteristic computations. Our main contributions are a multigrid convergent
    digital algorithm to compute the first intrinsic volume of a solid body in R^n
    as well as an appropriate integration pipeline to approximate integral-geometric
    integrals defined over the Grassmannian manifold.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Florian
  full_name: Pausinger, Florian
  id: 2A77D7A2-F248-11E8-B48F-1D18A9856A87
  last_name: Pausinger
  orcid: 0000-0002-8379-3768
citation:
  ama: Pausinger F. On the approximation of intrinsic volumes. 2015.
  apa: Pausinger, F. (2015). <i>On the approximation of intrinsic volumes</i>. Institute
    of Science and Technology Austria.
  chicago: Pausinger, Florian. “On the Approximation of Intrinsic Volumes.” Institute
    of Science and Technology Austria, 2015.
  ieee: F. Pausinger, “On the approximation of intrinsic volumes,” Institute of Science
    and Technology Austria, 2015.
  ista: Pausinger F. 2015. On the approximation of intrinsic volumes. Institute of
    Science and Technology Austria.
  mla: Pausinger, Florian. <i>On the Approximation of Intrinsic Volumes</i>. Institute
    of Science and Technology Austria, 2015.
  short: F. Pausinger, On the Approximation of Intrinsic Volumes, Institute of Science
    and Technology Austria, 2015.
date_created: 2018-12-11T11:51:48Z
date_published: 2015-06-01T00:00:00Z
date_updated: 2023-09-07T11:41:25Z
day: '01'
degree_awarded: PhD
department:
- _id: HeEd
language:
- iso: eng
month: '06'
oa_version: None
page: '144'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5808'
related_material:
  record:
  - id: '1662'
    relation: part_of_dissertation
    status: public
  - id: '1792'
    relation: part_of_dissertation
    status: public
  - id: '2255'
    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: On the approximation of intrinsic volumes
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2015'
...
---
_id: '1400'
abstract:
- lang: eng
  text: Cancer results from an uncontrolled growth of abnormal cells. Sequentially
    accumulated genetic and epigenetic alterations decrease cell death and increase
    cell replication. We used mathematical models to quantify the effect of driver
    gene mutations. The recently developed targeted therapies can lead to dramatic
    regressions. However, in solid cancers, clinical responses are often short-lived
    because resistant cancer cells evolve. We estimated that approximately 50 different
    mutations can confer resistance to a typical targeted therapeutic agent. We find
    that resistant cells are likely to be present in expanded subclones before the
    start of the treatment. The dominant strategy to prevent the evolution of resistance
    is combination therapy. Our analytical results suggest that in most patients,
    dual therapy, but not monotherapy, can result in long-term disease control. However,
    long-term control can only occur if there are no possible mutations in the genome
    that can cause cross-resistance to both drugs. Furthermore, we showed that simultaneous
    therapy with two drugs is much more likely to result in long-term disease control
    than sequential therapy with the same drugs. To improve our understanding of the
    underlying subclonal evolution we reconstruct the evolutionary history of a patient's
    cancer from next-generation sequencing data of spatially-distinct DNA samples.
    Using a quantitative measure of genetic relatedness, we found that pancreatic
    cancers and their metastases demonstrated a higher level of relatedness than that
    expected for any two cells randomly taken from a normal tissue. This minimal amount
    of genetic divergence among advanced lesions indicates that genetic heterogeneity,
    when quantitatively defined, is not a fundamental feature of the natural history
    of untreated pancreatic cancers. Our newly developed, phylogenomic tool Treeomics
    finds evidence for seeding patterns of metastases and can directly be used to
    discover rules governing the evolution of solid malignancies to transform cancer
    into a more predictable disease.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Johannes
  full_name: Reiter, Johannes
  id: 4A918E98-F248-11E8-B48F-1D18A9856A87
  last_name: Reiter
  orcid: 0000-0002-0170-7353
citation:
  ama: Reiter J. The subclonal evolution of cancer. 2015.
  apa: Reiter, J. (2015). <i>The subclonal evolution of cancer</i>. Institute of Science
    and Technology Austria.
  chicago: Reiter, Johannes. “The Subclonal Evolution of Cancer.” Institute of Science
    and Technology Austria, 2015.
  ieee: J. Reiter, “The subclonal evolution of cancer,” Institute of Science and Technology
    Austria, 2015.
  ista: Reiter J. 2015. The subclonal evolution of cancer. Institute of Science and
    Technology Austria.
  mla: Reiter, Johannes. <i>The Subclonal Evolution of Cancer</i>. Institute of Science
    and Technology Austria, 2015.
  short: J. Reiter, The Subclonal Evolution of Cancer, Institute of Science and Technology
    Austria, 2015.
date_created: 2018-12-11T11:51:48Z
date_published: 2015-04-01T00:00:00Z
date_updated: 2023-09-07T11:40:44Z
day: '01'
degree_awarded: PhD
department:
- _id: KrCh
language:
- iso: eng
month: '04'
oa_version: None
page: '183'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5807'
related_material:
  record:
  - id: '1709'
    relation: part_of_dissertation
    status: public
  - id: '2000'
    relation: part_of_dissertation
    status: public
  - id: '2247'
    relation: part_of_dissertation
    status: public
  - id: '2816'
    relation: part_of_dissertation
    status: public
  - id: '2858'
    relation: part_of_dissertation
    status: public
  - id: '3157'
    relation: part_of_dissertation
    status: public
  - id: '3260'
    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: The subclonal evolution of cancer
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2015'
...
---
_id: '1401'
abstract:
- lang: eng
  text: 'The human ability to recognize objects in complex scenes has driven research
    in the computer vision field over couple of decades. This thesis focuses on the
    object recognition task in images. That is, given the image, we want the computer
    system to be able to predict the class of the object that appears in the image.
    A recent successful attempt to bridge semantic understanding of the image perceived
    by humans and by computers uses attribute-based models. Attributes are semantic
    properties of the objects shared across different categories, which humans and
    computers can decide on. To explore the attribute-based models we take a statistical
    machine learning approach, and address two key learning challenges in view of
    object recognition task: learning augmented attributes as mid-level discriminative
    feature representation, and learning with attributes as privileged information.
    Our main contributions are parametric and non-parametric models and algorithms
    to solve these frameworks. In the parametric approach, we explore an autoencoder
    model combined with the large margin nearest neighbor principle for mid-level
    feature learning, and linear support vector machines for learning with privileged
    information. In the non-parametric approach, we propose a supervised Indian Buffet
    Process for automatic augmentation of semantic attributes, and explore the Gaussian
    Processes classification framework for learning with privileged information. A
    thorough experimental analysis shows the effectiveness of the proposed models
    in both parametric and non-parametric views.'
acknowledgement: "I would like to thank my supervisor, Christoph Lampert, for guidance
  throughout my studies and for patience in transforming me into a scientist, and
  my thesis committee, Chris Wojtan and Horst Bischof, for their help and advice.
  \r\n\r\nI would like to thank Elisabeth Hacker who perfectly assisted all my administrative
  needs and was always nice and friendly to me, and the campus team for making the
  IST Austria campus my second home. \r\nI was honored to collaborate with brilliant
  researchers and to learn from their experience. Undoubtedly, I learned most of all
  from Novi Quadrianto: brainstorming our projects and getting exciting results was
  the most enjoyable part of my work – thank you! I am also grateful to David Knowles,
  Zoubin Ghahramani, Daniel Hernández-Lobato, Kristian Kersting and Anastasia Pentina
  for the fantastic projects we worked on together, and to Kristen Grauman and Adriana
  Kovashka for the exceptional experience working with user studies. I would like
  to thank my colleagues at IST Austria and my office mates who shared their happy
  moods, scientific breakthroughs and thought-provoking conversations with me: Chao,
  Filip, Rustem, Asya, Sameh, Alex, Vlad, Mayu, Neel, Csaba, Thomas, Vladimir, Cristina,
  Alex Z., Avro, Amelie and Emilie, Andreas H. and Andreas E., Chris, Lena, Michael,
  Ali and Ipek, Vera, Igor, Katia. Special thanks to Morten for the countless games
  of table soccer we played together and the tournaments we teamed up for: we will
  definitely win next time:) A very warm hug to Asya for always being so inspiring
  and supportive to me, and for helping me to increase the proportion of female computer
  scientists in our group. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Viktoriia
  full_name: Sharmanska, Viktoriia
  id: 2EA6D09E-F248-11E8-B48F-1D18A9856A87
  last_name: Sharmanska
  orcid: 0000-0003-0192-9308
citation:
  ama: 'Sharmanska V. Learning with attributes for object recognition: Parametric
    and non-parametrics views. 2015. doi:<a href="https://doi.org/10.15479/at:ista:1401">10.15479/at:ista:1401</a>'
  apa: 'Sharmanska, V. (2015). <i>Learning with attributes for object recognition:
    Parametric and non-parametrics views</i>. Institute of Science and Technology
    Austria. <a href="https://doi.org/10.15479/at:ista:1401">https://doi.org/10.15479/at:ista:1401</a>'
  chicago: 'Sharmanska, Viktoriia. “Learning with Attributes for Object Recognition:
    Parametric and Non-Parametrics Views.” Institute of Science and Technology Austria,
    2015. <a href="https://doi.org/10.15479/at:ista:1401">https://doi.org/10.15479/at:ista:1401</a>.'
  ieee: 'V. Sharmanska, “Learning with attributes for object recognition: Parametric
    and non-parametrics views,” Institute of Science and Technology Austria, 2015.'
  ista: 'Sharmanska V. 2015. Learning with attributes for object recognition: Parametric
    and non-parametrics views. Institute of Science and Technology Austria.'
  mla: 'Sharmanska, Viktoriia. <i>Learning with Attributes for Object Recognition:
    Parametric and Non-Parametrics Views</i>. Institute of Science and Technology
    Austria, 2015, doi:<a href="https://doi.org/10.15479/at:ista:1401">10.15479/at:ista:1401</a>.'
  short: 'V. Sharmanska, Learning with Attributes for Object Recognition: Parametric
    and Non-Parametrics Views, Institute of Science and Technology Austria, 2015.'
date_created: 2018-12-11T11:51:48Z
date_published: 2015-04-01T00:00:00Z
date_updated: 2023-09-07T11:40:11Z
day: '01'
ddc:
- '000'
degree_awarded: PhD
department:
- _id: ChLa
- _id: GradSch
doi: 10.15479/at:ista:1401
file:
- access_level: open_access
  checksum: 3605b402bb6934e09ae4cf672c84baf7
  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T11:33:17Z
  date_updated: 2021-02-22T11:33:17Z
  file_id: '9177'
  file_name: 2015_Thesis_Sharmanska.pdf
  file_size: 7964342
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  success: 1
- access_level: closed
  checksum: e37593b3ee75bf3180629df2d6ca8f4e
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-16T14:40:45Z
  date_updated: 2021-11-17T13:47:24Z
  file_id: '10297'
  file_name: 2015_Thesis_Sharmanska_pdfa.pdf
  file_size: 7372241
  relation: main_file
file_date_updated: 2021-11-17T13:47:24Z
has_accepted_license: '1'
language:
- iso: eng
main_file_link:
- url: http://users.sussex.ac.uk/~nq28/viktoriia/Thesis_Sharmanska.pdf
month: '04'
oa: 1
oa_version: Published Version
page: '144'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5806'
status: public
supervisor:
- first_name: Christoph
  full_name: Lampert, Christoph
  id: 40C20FD2-F248-11E8-B48F-1D18A9856A87
  last_name: Lampert
  orcid: 0000-0001-8622-7887
title: 'Learning with attributes for object recognition: Parametric and non-parametrics
  views'
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2015'
...
---
_id: '1395'
abstract:
- lang: eng
  text: In this thesis I studied various individual and social immune defences employed
    by the invasive garden ant Lasius neglectus mostly against entomopathogenic fungi.  The
    first two chapters of this thesis address the phenomenon of 'social immunisation'.
    Social immunisation, that is the immunological protection of group members due
    to social contact to a pathogen-exposed nestmate, has been described in various
    social insect species against different types of pathogens. However, in the case
    of entomopathogenic fungi it has, so far, only been demonstrated that social immunisation
    exists at all. Its underlying mechanisms r any other properties were, however,
    unknown. In the first chapter of this thesis I identified the mechanistic basis
    of social immunisation in L. neglectus against the entomopathogenous fungus Metarhizium.
    I could show that nestmates of a pathogen-exposed individual contract low-level
    infections due to social interactions. These low-level infections are, however,
    non-lethal and cause an active stimulation of the immune system, which protects
    the nestmates upon subsequent pathogen encounters. In the second chapter of this
    thesis I investigated the specificity and colony level effects of social immunisation.
    I demonstrated that the protection conferred by social immunisation is highly
    specific, protecting ants only against the same pathogen strain. In addition,
    depending on the respective context, social immunisation may even cause fitness
    costs. I further showed that social immunisation crucially affects sanitary behaviour
    and disease dynamics within ant groups. In the third chapter of this thesis I
    studied the effects of the ectosymbiotic fungus Laboulbenia formicarum on its
    host L. neglectus. Although Laboulbeniales are the largest order of insect-parasitic
    fungi, research concerning host fitness consequence is sparse. I showed that highly
    Laboulbenia-infected ants sustain fitness costs under resource limitation, however,
    gain fitness benefits when exposed to an entomopathogenus fungus. These effects
    are probably cause by a prophylactic upregulation of behavioural as well as physiological
    immune defences in highly infected ants.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Matthias
  full_name: Konrad, Matthias
  id: 46528076-F248-11E8-B48F-1D18A9856A87
  last_name: Konrad
citation:
  ama: 'Konrad M. Immune defences in ants: Effects of social immunisation and a fungal
    ectosymbiont in the ant Lasius neglectus. 2014.'
  apa: 'Konrad, M. (2014). <i>Immune defences in ants: Effects of social immunisation
    and a fungal ectosymbiont in the ant Lasius neglectus</i>. Institute of Science
    and Technology Austria.'
  chicago: 'Konrad, Matthias. “Immune Defences in Ants: Effects of Social Immunisation
    and a Fungal Ectosymbiont in the Ant Lasius Neglectus.” Institute of Science and
    Technology Austria, 2014.'
  ieee: 'M. Konrad, “Immune defences in ants: Effects of social immunisation and a
    fungal ectosymbiont in the ant Lasius neglectus,” Institute of Science and Technology
    Austria, 2014.'
  ista: 'Konrad M. 2014. Immune defences in ants: Effects of social immunisation and
    a fungal ectosymbiont in the ant Lasius neglectus. Institute of Science and Technology
    Austria.'
  mla: 'Konrad, Matthias. <i>Immune Defences in Ants: Effects of Social Immunisation
    and a Fungal Ectosymbiont in the Ant Lasius Neglectus</i>. Institute of Science
    and Technology Austria, 2014.'
  short: 'M. Konrad, Immune Defences in Ants: Effects of Social Immunisation and a
    Fungal Ectosymbiont in the Ant Lasius Neglectus, Institute of Science and Technology
    Austria, 2014.'
date_created: 2018-12-11T11:51:46Z
date_published: 2014-02-01T00:00:00Z
date_updated: 2023-09-07T11:38:56Z
day: '01'
degree_awarded: PhD
department:
- _id: SyCr
language:
- iso: eng
month: '02'
oa_version: None
page: '131'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5814'
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: 'Immune defences in ants: Effects of social immunisation and a fungal ectosymbiont
  in the ant Lasius neglectus'
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2014'
...
---
_id: '1402'
abstract:
- lang: eng
  text: Phosphatidylinositol (Ptdlns) is a structural phospholipid that can be phosphorylated
    into various lipid signaling molecules, designated polyphosphoinositides (PPIs).
    The reversible phosphorylation of PPIs on the 3, 4, or 5 position of inositol
    is performed by a set of organelle-specific kinases and phosphatases, and the
    characteristic head groups make these molecules ideal for regulating biological
    processes in time and space. In yeast and mammals, Ptdlns3P and Ptdlns(3,5)P2
    play crucial roles in trafficking toward the lytic compartments, whereas the role
    in plants is not yet fully understood. Here we identified the role of a land plant-specific
    subgroup of PPI phosphatases, the suppressor of actin 2 (SAC2) to SAC5, during
    vauolar trafficking and morphogenesis in Arabidopsis thaliana. SAC2-SAC5 localize
    to the tonoplast along with Ptdlns3P, the presumable product of their activity.
    in SAC gain- and loss-of-function mutants, the levels of Ptdlns monophosphates
    and bisphosphates were changed, with opposite effects on the morphology of storage
    and lytic vacuoles, and the trafficking toward the vacuoles was defective. Moreover,
    multiple sac knockout mutants had an increased number of smaller storage and lytic
    vacuoles, whereas extralarge vacuoles were observed in the overexpression lines,
    correlating with various growth and developmental defects. The fragmented vacuolar
    phenotype of sac mutants could be mimicked by treating wild-type seedlings with
    Ptdlns(3,5)P2, corroborating that this PPI is important for vacuole morphology.
    Taken together, these results provide evidence that PPIs, together with their
    metabolic enzymes SAC2-SAC5, are crucial for vacuolar trafficking and for vacuolar
    morphology and function in plants.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Petra
  full_name: Marhavá, Petra
  id: 44E59624-F248-11E8-B48F-1D18A9856A87
  last_name: Marhavá
citation:
  ama: Marhavá P. Molecular mechanisms of patterning and subcellular trafficking in
    Arabidopsis thaliana. 2014.
  apa: Marhavá, P. (2014). <i>Molecular mechanisms of patterning and subcellular trafficking
    in Arabidopsis thaliana</i>. Institute of Science and Technology Austria.
  chicago: Marhavá, Petra. “Molecular Mechanisms of Patterning and Subcellular Trafficking
    in Arabidopsis Thaliana.” Institute of Science and Technology Austria, 2014.
  ieee: P. Marhavá, “Molecular mechanisms of patterning and subcellular trafficking
    in Arabidopsis thaliana,” Institute of Science and Technology Austria, 2014.
  ista: Marhavá P. 2014. Molecular mechanisms of patterning and subcellular trafficking
    in Arabidopsis thaliana. Institute of Science and Technology Austria.
  mla: Marhavá, Petra. <i>Molecular Mechanisms of Patterning and Subcellular Trafficking
    in Arabidopsis Thaliana</i>. Institute of Science and Technology Austria, 2014.
  short: P. Marhavá, Molecular Mechanisms of Patterning and Subcellular Trafficking
    in Arabidopsis Thaliana, Institute of Science and Technology Austria, 2014.
date_created: 2018-12-11T11:51:49Z
date_published: 2014-12-01T00:00:00Z
date_updated: 2023-09-07T11:39:38Z
day: '01'
degree_awarded: PhD
department:
- _id: JiFr
language:
- iso: eng
month: '12'
oa_version: None
page: '90'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5805'
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: Molecular mechanisms of patterning and subcellular trafficking in Arabidopsis
  thaliana
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2014'
...
---
_id: '1405'
abstract:
- lang: eng
  text: "Motivated by the analysis of highly dynamic message-passing systems, i.e.
    unbounded thread creation, mobility, etc. we present a framework for the analysis
    of depth-bounded systems. Depth-bounded systems are one of the most expressive
    known fragment of the π-calculus for which interesting verification problems are
    still decidable. Even though they are infinite state systems depth-bounded systems
    are well-structured, thus can be analyzed algorithmically. We give an interpretation
    of depth-bounded systems as graph-rewriting systems. This gives more flexibility
    and ease of use to apply depth-bounded systems to other type of systems like shared
    memory concurrency.\r\n\r\nFirst, we develop an adequate domain of limits for
    depth-bounded systems, a prerequisite for the effective representation of downward-closed
    sets. Downward-closed sets are needed by forward saturation-based algorithms to
    represent potentially infinite sets of states. Then, we present an abstract interpretation
    framework to compute the covering set of well-structured transition systems. Because,
    in general, the covering set is not computable, our abstraction over-approximates
    the actual covering set. Our abstraction captures the essence of acceleration
    based-algorithms while giving up enough precision to ensure convergence. We have
    implemented the analysis in the PICASSO tool and show that it is accurate in practice.
    Finally, we build some further analyses like termination using the covering set
    as starting point."
acknowledgement: "This work was supported in part by the Austrian Science Fund NFN
  RiSE (Rigorous Systems Engineering) and by the ERC Advanced Grant QUAREM (Quantitative
  Reactve Modeling).\r\nChapter 2, 3, and 4 are joint work with Thomas A. Henzinger
  and Thomas Wies. Chapter 2 was published in FoSSaCS 2010 as “Forward Analysis of
  Depth-Bounded Processes” [112]. Chapter 3 was published in VMCAI 2012 as “Ideal
  Abstractions for Well-Structured Transition Systems” [114]. Chap- ter 5.1 is joint
  work with Kshitij Bansal, Eric Koskinen, and Thomas Wies. It was published in TACAS
  2013 as “Structural Counter Abstraction” [13]. The author’s contribution in this
  part is mostly related to the implementation. The theory required to understand
  the method and its implementation is quickly recalled to make the thesis self-contained,
  but should not be considered as a contribution. For the details of the methods,
  we refer the reader to the orig- inal publication [13] and the corresponding technical
  report [14]. Chapter 5.2 is ongoing work with Shahram Esmaeilsabzali, Rupak Majumdar,
  and Thomas Wies. I also would like to thank the people who supported over the past
  4 years. My advisor Thomas A. Henzinger who gave me a lot of freedom to work on
  projects I was interested in. My collaborators, especially Thomas Wies with whom
  I worked since the beginning. The members of my thesis committee, Viktor Kun- cak
  and Rupak Majumdar, who also agreed to advise me. Simon Aeschbacher, Pavol Cerny,
  Cezara Dragoi, Arjun Radhakrishna, my family, friends and col- leagues who created
  an enjoyable environment. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Damien
  full_name: Zufferey, Damien
  id: 4397AC76-F248-11E8-B48F-1D18A9856A87
  last_name: Zufferey
  orcid: 0000-0002-3197-8736
citation:
  ama: Zufferey D. Analysis of dynamic message passing programs. 2013. doi:<a href="https://doi.org/10.15479/at:ista:1405">10.15479/at:ista:1405</a>
  apa: Zufferey, D. (2013). <i>Analysis of dynamic message passing programs</i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:1405">https://doi.org/10.15479/at:ista:1405</a>
  chicago: Zufferey, Damien. “Analysis of Dynamic Message Passing Programs.” Institute
    of Science and Technology Austria, 2013. <a href="https://doi.org/10.15479/at:ista:1405">https://doi.org/10.15479/at:ista:1405</a>.
  ieee: D. Zufferey, “Analysis of dynamic message passing programs,” Institute of
    Science and Technology Austria, 2013.
  ista: Zufferey D. 2013. Analysis of dynamic message passing programs. Institute
    of Science and Technology Austria.
  mla: Zufferey, Damien. <i>Analysis of Dynamic Message Passing Programs</i>. Institute
    of Science and Technology Austria, 2013, doi:<a href="https://doi.org/10.15479/at:ista:1405">10.15479/at:ista:1405</a>.
  short: D. Zufferey, Analysis of Dynamic Message Passing Programs, Institute of Science
    and Technology Austria, 2013.
date_created: 2018-12-11T11:51:50Z
date_published: 2013-09-05T00:00:00Z
date_updated: 2023-09-07T11:36:37Z
day: '05'
ddc:
- '000'
degree_awarded: PhD
department:
- _id: ToHe
- _id: GradSch
doi: 10.15479/at:ista:1405
ec_funded: 1
file:
- access_level: open_access
  checksum: ed2d7b52933d134e8dc69d569baa284e
  content_type: application/pdf
  creator: dernst
  date_created: 2021-02-22T11:28:36Z
  date_updated: 2021-02-22T11:28:36Z
  file_id: '9176'
  file_name: 2013_Zufferey_thesis_final.pdf
  file_size: 1514906
  relation: main_file
  success: 1
- access_level: closed
  checksum: cecc4c4b14225bee973d32e3dba91a55
  content_type: application/pdf
  creator: cchlebak
  date_created: 2021-11-16T14:42:52Z
  date_updated: 2021-11-17T13:47:58Z
  file_id: '10298'
  file_name: 2013_Zufferey_thesis_final_pdfa.pdf
  file_size: 1378313
  relation: main_file
file_date_updated: 2021-11-17T13:47:58Z
has_accepted_license: '1'
language:
- iso: eng
main_file_link:
- url: http://dzufferey.github.io/files/2013_thesis.pdf
month: '09'
oa: 1
oa_version: Published Version
page: '134'
project:
- _id: 25832EC2-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: S 11407_N23
  name: Rigorous Systems Engineering
- _id: 25EE3708-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '267989'
  name: Quantitative Reactive Modeling
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5802'
related_material:
  record:
  - id: '2847'
    relation: part_of_dissertation
    status: public
  - id: '3251'
    relation: part_of_dissertation
    status: public
  - id: '4361'
    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: Analysis of dynamic message passing programs
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2013'
...
---
_id: '1406'
abstract:
- lang: eng
  text: Epithelial spreading is a critical part of various developmental and wound
    repair processes. Here we use zebrafish epiboly as a model system to study the
    cellular and molecular mechanisms underlying the spreading of epithelial sheets.
    During zebrafish epiboly the enveloping cell layer (EVL), a simple squamous epithelium,
    spreads over the embryo to eventually cover the entire yolk cell by the end of
    gastrulation. The EVL leading edge is anchored through tight junctions to the
    yolk syncytial layer (YSL), where directly adjacent to the EVL margin a contractile
    actomyosin ring is formed that is thought to drive EVL epiboly. The prevalent
    view in the field was that the contractile ring exerts a pulling force on the
    EVL margin, which pulls the EVL towards the vegetal pole. However, how this force
    is generated and how it affects EVL morphology still remains elusive. Moreover,
    the cellular mechanisms mediating the increase in EVL surface area, while maintaining
    tissue integrity and function are still unclear. Here we show that the YSL actomyosin
    ring pulls on the EVL margin by two distinct force-generating mechanisms. One
    mechanism is based on contraction of the ring around its circumference, as previously
    proposed. The second mechanism is based on actomyosin retrogade flows, generating
    force through resistance against the substrate. The latter can function at any
    epiboly stage even in situations where the contraction-based mechanism is unproductive.
    Additionally, we demonstrate that during epiboly the EVL is subjected to anisotropic
    tension, which guides the orientation of EVL cell division along the main axis
    (animal-vegetal) of tension. The influence of tension in cell division orientation
    involves cell elongation and requires myosin-2 activity for proper spindle alignment.
    Strikingly, we reveal that tension-oriented cell divisions release anisotropic
    tension within the EVL and that in the absence of such divisions, EVL cells undergo
    ectopic fusions. We conclude that forces applied to the EVL by the action of the
    YSL actomyosin ring generate a tension anisotropy in the EVL that orients cell
    divisions, which in turn limit tissue tension increase thereby facilitating tissue
    spreading.
acknowledged_ssus:
- _id: Bio
- _id: PreCl
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Pedro
  full_name: Campinho, Pedro
  id: 3AFBBC42-F248-11E8-B48F-1D18A9856A87
  last_name: Campinho
  orcid: 0000-0002-8526-5416
citation:
  ama: 'Campinho P. Mechanics of zebrafish epiboly: Tension-oriented cell divisions
    limit anisotropic tissue tension in epithelial spreading. 2013.'
  apa: 'Campinho, P. (2013). <i>Mechanics of zebrafish epiboly: Tension-oriented cell
    divisions limit anisotropic tissue tension in epithelial spreading</i>. Institute
    of Science and Technology Austria.'
  chicago: 'Campinho, Pedro. “Mechanics of Zebrafish Epiboly: Tension-Oriented Cell
    Divisions Limit Anisotropic Tissue Tension in Epithelial Spreading.” Institute
    of Science and Technology Austria, 2013.'
  ieee: 'P. Campinho, “Mechanics of zebrafish epiboly: Tension-oriented cell divisions
    limit anisotropic tissue tension in epithelial spreading,” Institute of Science
    and Technology Austria, 2013.'
  ista: 'Campinho P. 2013. Mechanics of zebrafish epiboly: Tension-oriented cell divisions
    limit anisotropic tissue tension in epithelial spreading. Institute of Science
    and Technology Austria.'
  mla: 'Campinho, Pedro. <i>Mechanics of Zebrafish Epiboly: Tension-Oriented Cell
    Divisions Limit Anisotropic Tissue Tension in Epithelial Spreading</i>. Institute
    of Science and Technology Austria, 2013.'
  short: 'P. Campinho, Mechanics of Zebrafish Epiboly: Tension-Oriented Cell Divisions
    Limit Anisotropic Tissue Tension in Epithelial Spreading, Institute of Science
    and Technology Austria, 2013.'
date_created: 2018-12-11T11:51:50Z
date_published: 2013-10-01T00:00:00Z
date_updated: 2023-09-07T11:36:07Z
day: '01'
degree_awarded: PhD
department:
- _id: CaHe
language:
- iso: eng
month: '10'
oa_version: None
page: '123'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5801'
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: 'Mechanics of zebrafish epiboly: Tension-oriented cell divisions limit anisotropic
  tissue tension in epithelial spreading'
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2013'
...
---
_id: '2964'
abstract:
- lang: eng
  text: 'CA3 pyramidal neurons are important for memory formation and pattern completion
    in the hippocampal network. These neurons receive multiple excitatory inputs from
    numerous sources. Therefore, the rules of spatiotemporal integration of multiple
    synaptic inputs and propagation of action potentials are important to understand
    how CA3 neurons contribute to higher brain functions at cellular level. By using
    confocally targeted patch-clamp recording techniques, we investigated the biophysical
    properties of rat CA3 pyramidal neuron dendrites. We found two distinct dendritic
    domains critical for action potential initiation and propagation: In the proximal
    domain, action potentials initiated in the axon backpropagate actively with large
    amplitude and fast time course. In the distal domain, Na+-channel mediated dendritic
    spikes are efficiently evoked by local dendritic depolarization or waveforms mimicking
    synaptic events. These findings can be explained by a high Na+-to-K+ conductance
    density ratio of CA3 pyramidal neuron dendrites. The results challenge the prevailing
    view that proximal mossy fiber inputs activate CA3 pyramidal neurons more efficiently
    than distal perforant inputs by showing that the distal synapses trigger a different
    form of activity represented by dendritic spikes. The high probability of dendritic
    spike initiation in the distal area may enhance the computational power of CA3
    pyramidal neurons in the hippocampal network.  '
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Sooyun
  full_name: Kim, Sooyun
  id: 394AB1C8-F248-11E8-B48F-1D18A9856A87
  last_name: Kim
citation:
  ama: Kim S. Active properties of hippocampal CA3 pyramidal neuron dendrites. 2012.
  apa: Kim, S. (2012). <i>Active properties of hippocampal CA3 pyramidal neuron dendrites</i>.
    Institute of Science and Technology Austria.
  chicago: Kim, Sooyun. “Active Properties of Hippocampal CA3 Pyramidal Neuron Dendrites.”
    Institute of Science and Technology Austria, 2012.
  ieee: S. Kim, “Active properties of hippocampal CA3 pyramidal neuron dendrites,”
    Institute of Science and Technology Austria, 2012.
  ista: Kim S. 2012. Active properties of hippocampal CA3 pyramidal neuron dendrites.
    Institute of Science and Technology Austria.
  mla: Kim, Sooyun. <i>Active Properties of Hippocampal CA3 Pyramidal Neuron Dendrites</i>.
    Institute of Science and Technology Austria, 2012.
  short: S. Kim, Active Properties of Hippocampal CA3 Pyramidal Neuron Dendrites,
    Institute of Science and Technology Austria, 2012.
date_created: 2018-12-11T12:00:35Z
date_published: 2012-06-01T00:00:00Z
date_updated: 2023-09-07T11:43:51Z
day: '01'
degree_awarded: PhD
department:
- _id: PeJo
- _id: GradSch
language:
- iso: eng
month: '06'
oa_version: None
page: '65'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '3755'
related_material:
  record:
  - id: '3258'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Peter M
  full_name: Jonas, Peter M
  id: 353C1B58-F248-11E8-B48F-1D18A9856A87
  last_name: Jonas
  orcid: 0000-0001-5001-4804
title: Active properties of hippocampal CA3 pyramidal neuron dendrites
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2012'
...
---
_id: '3273'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Jean-Léon
  full_name: Maître, Jean-Léon
  id: 48F1E0D8-F248-11E8-B48F-1D18A9856A87
  last_name: Maître
  orcid: 0000-0002-3688-1474
citation:
  ama: Maître J-L. Mechanics of adhesion and de‐adhesion in zebrafish germ layer progenitors.
    2011.
  apa: Maître, J.-L. (2011). <i>Mechanics of adhesion and de‐adhesion in zebrafish
    germ layer progenitors</i>. Institute of Science and Technology Austria.
  chicago: Maître, Jean-Léon. “Mechanics of Adhesion and De‐adhesion in Zebrafish
    Germ Layer Progenitors.” Institute of Science and Technology Austria, 2011.
  ieee: J.-L. Maître, “Mechanics of adhesion and de‐adhesion in zebrafish germ layer
    progenitors,” Institute of Science and Technology Austria, 2011.
  ista: Maître J-L. 2011. Mechanics of adhesion and de‐adhesion in zebrafish germ
    layer progenitors. Institute of Science and Technology Austria.
  mla: Maître, Jean-Léon. <i>Mechanics of Adhesion and De‐adhesion in Zebrafish Germ
    Layer Progenitors</i>. Institute of Science and Technology Austria, 2011.
  short: J.-L. Maître, Mechanics of Adhesion and De‐adhesion in Zebrafish Germ Layer
    Progenitors, Institute of Science and Technology Austria, 2011.
date_created: 2018-12-11T12:02:23Z
date_published: 2011-12-12T00:00:00Z
date_updated: 2023-09-07T11:30:16Z
day: '12'
degree_awarded: PhD
department:
- _id: CaHe
language:
- iso: eng
month: '12'
oa_version: None
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '3373'
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: Mechanics of adhesion and de‐adhesion in zebrafish germ layer progenitors
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2011'
...
---
_id: '3275'
abstract:
- lang: eng
  text: 'Chemokines organize immune cell trafficking by inducing either directed (tactic)
    or random (kinetic) migration and by activating integrins in order to support
    surface adhesion (haptic). Beyond that the same chemokines can establish clearly
    defined functional areas in secondary lymphoid organs. Until now it is unclear
    how chemokines can fulfill such diverse functions. One decisive prerequisite to
    explain these capacities is to know how chemokines are presented in tissue. In
    theory chemokines could occur either soluble or immobilized, and could be distributed
    either homogenously or as a concentration gradient. To dissect if and how the
    presenting mode of chemokines influences immune cells, I tested the response of
    dendritic cells (DCs) to differentially displayed chemokines. DCs are antigen
    presenting cells that reside in the periphery and migrate into draining lymph
    nodes (LNs) once exposed to inflammatory stimuli to activate naïve T cells. DCs
    are guided to and within the LN by the chemokine receptor CCR7, which has two
    ligands, the chemokines CCL19 and CCL21. Both CCR7 ligands are expressed by fibroblastic
    reticular cells in the LN, but differ in their ability to bind to heparan sulfate
    residues. CCL21 has a highly charged C-terminal extension, which mediates binding
    to anionic surfaces, whereas CCL19 is lacking such residues and likely distributes
    as a soluble molecule. This study shows that surface-bound CCL21 causes random,
    haptokinetic DC motility, which is confined to the chemokine coated area by insideout
    activation of β2 integrins that mediate cell binding to the surface. CCL19 on
    the other hand forms concentration gradients which trigger directional, chemotactic
    movement, but no surface adhesion. In addition DCs can actively manipulate this
    system by recruiting and activating serine proteases on their surfaces, which
    create - by proteolytically removing the adhesive C-terminus - a solubilized variant
    of CCL21 that functionally resembles CCL19. By generating a CCL21 concentration
    gradient DCs establish a positive feedback loop to recruit further DCs from the
    periphery to the CCL21 coated region. In addition DCs can sense chemotactic gradients
    as well as immobilized haptokinetic fields at the same time and integrate these
    signals. The result is chemotactically biased haptokinesis - directional migration
    confined to a chemokine coated track or area - which could explain the dynamic
    but spatially tightly controlled swarming leukocyte locomotion patterns that have
    been observed in lymphatic organs by intravital microscopists. The finding that
    DCs can approach soluble cues in a non-adhesive manner while they attach to surfaces
    coated with immobilized cues raises the question how these cells transmit intracellular
    forces to the environment, especially in the non-adherent migration mode. In order
    to migrate, cells have to generate and transmit force to the extracellular substrate.
    Force transmission is the prerequisite to procure an expansion of the leading
    edge and a forward motion of the whole cell body. In the current conceptions actin
    polymerization at the leading edge is coupled to extracellular ligands via the
    integrin family of transmembrane receptors, which allows the transmission of intracellular
    force. Against the paradigm of force transmission during migration, leukocytes,
    like DCs, are able to migrate in threedimensional environments without using integrin
    transmembrane receptors (Lämmermann et al., 2008). This reflects the biological
    function of leukocytes, as they can invade almost all tissues, whereby their migration
    has to be independent from the extracellular environment. How the cells can achieve
    this is unclear. For this study I examined DC migration in a defined threedimensional
    environment and highlighted actin-dynamics with the probe Lifeact-GFP. The result
    was that chemotactic DCs can switch between integrin-dependent and integrin- independent
    locomotion and can thereby adapt to the adhesive properties of their environment.
    If the cells are able to couple their actin cytoskeleton to the substrate, actin
    polymerization is entirely converted into protrusion. Without coupling the actin
    cortex undergoes slippage and retrograde actin flow can be observed. But retrograde
    actin flow can be completely compensated by higher actin polymerization rate keeping
    the migration velocity and the shape of the cells unaltered. Mesenchymal cells
    like fibroblast cannot balance the loss of adhesive interaction, cannot protrude
    into open space and, therefore, strictly depend on integrinmediated force coupling.
    This leukocyte specific phenomenon of “adaptive force transmission” endows these
    cells with the unique ability to transit and invade almost every type of tissue. '
acknowledgement: "I would like to express my sincere gratitude to the following people
  who made with their continuous support and encouragement this thesis possible: First,
  I want to thank Prof. Dr. Michael Sixt for his excellent supervision and mentoring,
  especially for the nice, relaxed working atmosphere, a lot of brilliant ideas and
  the freedom to work in my own way.\r\n\r\nProf. Dr. Reinhard Fässler for his constant
  support of the Sixt lab and for providing excellent working conditions. \r\n\r\nProf.
  Dr. Sanjiv Luther and Prof. Dr. Tobias Bollenbach for agreeing to be member of my
  thesis committee and to evaluate my work.\r\n\r\nDr. Walther Göhring, Carmen Schmitz,
  the Recombinant Protein Production core facility and the animal care takers for
  providing the “infrastructure” for this thesis. \r\n\r\nProf. Dr. Daniel Legler,
  Markus Bruckner and Dr. Julien Polleux for very fruitful collaborations and discussions.\r\n\r\nMy
  labmates for their help, a lot of discussions and to make the Sixt lab to a convenient
  place to work : Karin Hirsch, Tim Lämmeramnn, Holger Pflicke, Jörg Renkawitz, Michele
  Weber and Alexander Eichner All members of the Department of Molecular Medicine
  for their help. Especially I want to thank Sarah Schmidt, Karin Hirsch and Raphael
  Ruppert for their friendship, nice chats and their uncensored point of view. "
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Kathrin
  full_name: Schumann, Kathrin
  id: F44D762E-4F9D-11E9-B64C-9EB26CEFFB5F
  last_name: Schumann
citation:
  ama: Schumann K. The role of chemotactic gradients in dendritic cell migration.
    2011.
  apa: Schumann, K. (2011). <i>The role of chemotactic gradients in dendritic cell
    migration</i>. Institute of Science and Technology Austria.
  chicago: Schumann, Kathrin. “The Role of Chemotactic Gradients in Dendritic Cell
    Migration.” Institute of Science and Technology Austria, 2011.
  ieee: K. Schumann, “The role of chemotactic gradients in dendritic cell migration,”
    Institute of Science and Technology Austria, 2011.
  ista: Schumann K. 2011. The role of chemotactic gradients in dendritic cell migration.
    Institute of Science and Technology Austria.
  mla: Schumann, Kathrin. <i>The Role of Chemotactic Gradients in Dendritic Cell Migration</i>.
    Institute of Science and Technology Austria, 2011.
  short: K. Schumann, The Role of Chemotactic Gradients in Dendritic Cell Migration,
    Institute of Science and Technology Austria, 2011.
date_created: 2018-12-11T12:02:24Z
date_published: 2011-03-01T00:00:00Z
date_updated: 2023-09-07T11:31:48Z
day: '01'
ddc:
- '570'
- '579'
degree_awarded: PhD
department:
- _id: MiSi
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has_accepted_license: '1'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
page: '141'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '3371'
pubrep_id: '11'
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: The role of chemotactic gradients in dendritic cell migration
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2011'
...
