---
_id: '10299'
abstract:
- lang: eng
text: Turbulence generally arises in shear flows if velocities and hence, inertial
forces are sufficiently large. In striking contrast, viscoelastic fluids can exhibit
disordered motion even at vanishing inertia. Intermediate between these cases,
a state of chaotic motion, “elastoinertial turbulence” (EIT), has been observed
in a narrow Reynolds number interval. We here determine the origin of EIT in experiments
and show that characteristic EIT structures can be detected across an unexpectedly
wide range of parameters. Close to onset, a pattern of chevron-shaped streaks
emerges in qualitative agreement with linear and weakly nonlinear theory. However,
in experiments, the dynamics remain weakly chaotic, and the instability can be
traced to far lower Reynolds numbers than permitted by theory. For increasing
inertia, the flow undergoes a transformation to a wall mode composed of inclined
near-wall streaks and shear layers. This mode persists to what is known as the
“maximum drag reduction limit,” and overall EIT is found to dominate viscoelastic
flows across more than three orders of magnitude in Reynolds number.
acknowledgement: We thank Y. Dubief, R. Kerswell, E. Marensi, V. Shankar, V. Steinberg,
and V. Terrapon for discussions and helpful comments. A.V. and B.H. acknowledge
funding from the Austrian Science Fund, grant I4188-N30, within the Deutsche Forschungsgemeinschaft
research unit FOR 2688.
article_number: e2102350118
article_processing_charge: No
article_type: original
author:
- first_name: George H
full_name: Choueiri, George H
id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
last_name: Choueiri
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Sarath
full_name: Sankar, Sarath
last_name: Sankar
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. Experimental observation
of the origin and structure of elastoinertial turbulence. Proceedings of the
National Academy of Sciences. 2021;118(45). doi:10.1073/pnas.2102350118
apa: Choueiri, G. H., Lopez Alonso, J. M., Varshney, A., Sankar, S., & Hof,
B. (2021). Experimental observation of the origin and structure of elastoinertial
turbulence. Proceedings of the National Academy of Sciences. National Academy
of Sciences. https://doi.org/10.1073/pnas.2102350118
chicago: Choueiri, George H, Jose M Lopez Alonso, Atul Varshney, Sarath Sankar,
and Björn Hof. “Experimental Observation of the Origin and Structure of Elastoinertial
Turbulence.” Proceedings of the National Academy of Sciences. National
Academy of Sciences, 2021. https://doi.org/10.1073/pnas.2102350118.
ieee: G. H. Choueiri, J. M. Lopez Alonso, A. Varshney, S. Sankar, and B. Hof, “Experimental
observation of the origin and structure of elastoinertial turbulence,” Proceedings
of the National Academy of Sciences, vol. 118, no. 45. National Academy of
Sciences, 2021.
ista: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. 2021. Experimental
observation of the origin and structure of elastoinertial turbulence. Proceedings
of the National Academy of Sciences. 118(45), e2102350118.
mla: Choueiri, George H., et al. “Experimental Observation of the Origin and Structure
of Elastoinertial Turbulence.” Proceedings of the National Academy of Sciences,
vol. 118, no. 45, e2102350118, National Academy of Sciences, 2021, doi:10.1073/pnas.2102350118.
short: G.H. Choueiri, J.M. Lopez Alonso, A. Varshney, S. Sankar, B. Hof, Proceedings
of the National Academy of Sciences 118 (2021).
date_created: 2021-11-17T13:24:24Z
date_published: 2021-11-03T00:00:00Z
date_updated: 2023-08-14T11:50:10Z
day: '03'
department:
- _id: BjHo
doi: 10.1073/pnas.2102350118
external_id:
arxiv:
- '2103.00023'
isi:
- '000720926900019'
pmid:
- ' 34732570'
intvolume: ' 118'
isi: 1
issue: '45'
keyword:
- multidisciplinary
- elastoinertial turbulence
- viscoelastic flows
- elastic instability
- drag reduction
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2103.00023
month: '11'
oa: 1
oa_version: Preprint
pmid: 1
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: I04188
name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
publication: Proceedings of the National Academy of Sciences
publication_identifier:
eissn:
- 1091-6490
issn:
- 0027-8424
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: Experimental observation of the origin and structure of elastoinertial turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 118
year: '2021'
...
---
_id: '9728'
abstract:
- lang: eng
text: "Most real-world flows are multiphase, yet we know little about them compared
to their single-phase counterparts. Multiphase flows are more difficult to investigate
as their dynamics occur in large parameter space and involve complex phenomena
such as preferential concentration, turbulence modulation, non-Newtonian rheology,
etc. Over the last few decades, experiments in particle-laden flows have taken
a back seat in favour of ever-improving computational resources. However, computers
are still not powerful enough to simulate a real-world fluid with millions of
finite-size particles. Experiments are essential not only because they offer a
reliable way to investigate real-world multiphase flows but also because they
serve to validate numerical studies and steer the research in a relevant direction.
In this work, we have experimentally investigated particle-laden flows in pipes,
and in particular, examined the effect of particles on the laminar-turbulent transition
and the drag scaling in turbulent flows.\r\n\r\nFor particle-laden pipe flows,
an earlier study [Matas et al., 2003] reported how the sub-critical (i.e., hysteretic)
transition that occurs via localised turbulent structures called puffs is affected
by the addition of particles. In this study, in addition to this known transition,
we found a super-critical transition to a globally fluctuating state with increasing
particle concentration. At the same time, the Newtonian-type transition via puffs
is delayed to larger Reynolds numbers. At an even higher concentration, only the
globally fluctuating state is found. The dynamics of particle-laden flows are
hence determined by two competing instabilities that give rise to three flow regimes:
Newtonian-type turbulence at low, a particle-induced globally fluctuating state
at high, and a coexistence state at intermediate concentrations.\r\n\r\nThe effect
of particles on turbulent drag is ambiguous, with studies reporting drag reduction,
no net change, and even drag increase. The ambiguity arises because, in addition
to particle concentration, particle shape, size, and density also affect the net
drag. Even similar particles might affect the flow dissimilarly in different Reynolds
number and concentration ranges. In the present study, we explored a wide range
of both Reynolds number and concentration, using spherical as well as cylindrical
particles. We found that the spherical particles do not reduce drag while the
cylindrical particles are drag-reducing within a specific Reynolds number interval.
The interval strongly depends on the particle concentration and the relative size
of the pipe and particles. Within this interval, the magnitude of drag reduction
reaches a maximum. These drag reduction maxima appear to fall onto a distinct
power-law curve irrespective of the pipe diameter and particle concentration,
and this curve can be considered as the maximum drag reduction asymptote for a
given fibre shape. Such an asymptote is well known for polymeric flows but had
not been identified for particle-laden flows prior to this work."
acknowledged_ssus:
- _id: M-Shop
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Nishchal
full_name: Agrawal, Nishchal
id: 469E6004-F248-11E8-B48F-1D18A9856A87
last_name: Agrawal
citation:
ama: Agrawal N. Transition to turbulence and drag reduction in particle-laden pipe
flows. 2021. doi:10.15479/at:ista:9728
apa: Agrawal, N. (2021). Transition to turbulence and drag reduction in particle-laden
pipe flows. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:9728
chicago: Agrawal, Nishchal. “Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows.” Institute of Science and Technology Austria, 2021. https://doi.org/10.15479/at:ista:9728.
ieee: N. Agrawal, “Transition to turbulence and drag reduction in particle-laden
pipe flows,” Institute of Science and Technology Austria, 2021.
ista: Agrawal N. 2021. Transition to turbulence and drag reduction in particle-laden
pipe flows. Institute of Science and Technology Austria.
mla: Agrawal, Nishchal. Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows. Institute of Science and Technology Austria, 2021, doi:10.15479/at:ista:9728.
short: N. Agrawal, Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows, Institute of Science and Technology Austria, 2021.
date_created: 2021-07-27T13:40:30Z
date_published: 2021-07-29T00:00:00Z
date_updated: 2024-02-28T13:14:39Z
day: '29'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: GradSch
- _id: BjHo
doi: 10.15479/at:ista:9728
file:
- access_level: closed
checksum: 77436be3563a90435024307b1b5ee7e8
content_type: application/x-zip-compressed
creator: nagrawal
date_created: 2021-07-28T13:32:02Z
date_updated: 2022-07-29T22:30:05Z
embargo_to: open_access
file_id: '9744'
file_name: Transition to Turbulence and Drag Reduction in Particle-Laden Pipe Flows.zip
file_size: 22859658
relation: source_file
- access_level: open_access
checksum: 72a891d7daba85445c29b868c22575ed
content_type: application/pdf
creator: nagrawal
date_created: 2021-07-28T13:32:05Z
date_updated: 2022-07-29T22:30:05Z
embargo: 2022-07-28
file_id: '9745'
file_name: Transition to Turbulence and Drag Reduction in Particle-Laden Pipe Flows.pdf
file_size: 18658048
relation: main_file
file_date_updated: 2022-07-29T22:30:05Z
has_accepted_license: '1'
keyword:
- Drag Reduction
- Transition to Turbulence
- Multiphase Flows
- particle Laden Flows
- Complex Flows
- Experiments
- Fluid Dynamics
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '07'
oa: 1
oa_version: Published Version
page: '118'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '6189'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: Transition to turbulence and drag reduction in particle-laden pipe flows
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...
---
_id: '7364'
abstract:
- lang: eng
text: We present nsCouette, a highly scalable software tool to solve the Navier–Stokes
equations for incompressible fluid flow between differentially heated and independently
rotating, concentric cylinders. It is based on a pseudospectral spatial discretization
and dynamic time-stepping. It is implemented in modern Fortran with a hybrid MPI-OpenMP
parallelization scheme and thus designed to compute turbulent flows at high Reynolds
and Rayleigh numbers. An additional GPU implementation (C-CUDA) for intermediate
problem sizes and a version for pipe flow (nsPipe) are also provided.
article_number: '100395'
article_processing_charge: No
article_type: original
author:
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Daniel
full_name: Feldmann, Daniel
last_name: Feldmann
- first_name: Markus
full_name: Rampp, Markus
last_name: Rampp
- first_name: Alberto
full_name: Vela-Martín, Alberto
last_name: Vela-Martín
- first_name: Liang
full_name: Shi, Liang
id: 374A3F1A-F248-11E8-B48F-1D18A9856A87
last_name: Shi
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
citation:
ama: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. nsCouette
– A high-performance code for direct numerical simulations of turbulent Taylor–Couette
flow. SoftwareX. 2020;11. doi:10.1016/j.softx.2019.100395
apa: Lopez Alonso, J. M., Feldmann, D., Rampp, M., Vela-Martín, A., Shi, L., &
Avila, M. (2020). nsCouette – A high-performance code for direct numerical simulations
of turbulent Taylor–Couette flow. SoftwareX. Elsevier. https://doi.org/10.1016/j.softx.2019.100395
chicago: Lopez Alonso, Jose M, Daniel Feldmann, Markus Rampp, Alberto Vela-Martín,
Liang Shi, and Marc Avila. “NsCouette – A High-Performance Code for Direct Numerical
Simulations of Turbulent Taylor–Couette Flow.” SoftwareX. Elsevier, 2020.
https://doi.org/10.1016/j.softx.2019.100395.
ieee: J. M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, and M.
Avila, “nsCouette – A high-performance code for direct numerical simulations of
turbulent Taylor–Couette flow,” SoftwareX, vol. 11. Elsevier, 2020.
ista: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. 2020.
nsCouette – A high-performance code for direct numerical simulations of turbulent
Taylor–Couette flow. SoftwareX. 11, 100395.
mla: Lopez Alonso, Jose M., et al. “NsCouette – A High-Performance Code for Direct
Numerical Simulations of Turbulent Taylor–Couette Flow.” SoftwareX, vol.
11, 100395, Elsevier, 2020, doi:10.1016/j.softx.2019.100395.
short: J.M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, M. Avila,
SoftwareX 11 (2020).
date_created: 2020-01-26T23:00:35Z
date_published: 2020-01-17T00:00:00Z
date_updated: 2023-08-17T14:29:59Z
day: '17'
ddc:
- '000'
department:
- _id: BjHo
doi: 10.1016/j.softx.2019.100395
external_id:
arxiv:
- '1908.00587'
isi:
- '000552271200011'
file:
- access_level: open_access
checksum: 2af1a1a3cc33557b345145276f221668
content_type: application/pdf
creator: dernst
date_created: 2020-01-27T07:32:46Z
date_updated: 2020-07-14T12:47:56Z
file_id: '7365'
file_name: 2020_SoftwareX_Lopez.pdf
file_size: 679707
relation: main_file
file_date_updated: 2020-07-14T12:47:56Z
has_accepted_license: '1'
intvolume: ' 11'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-nd/4.0/
month: '01'
oa: 1
oa_version: Published Version
publication: SoftwareX
publication_identifier:
eissn:
- '23527110'
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: nsCouette – A high-performance code for direct numerical simulations of turbulent
Taylor–Couette flow
tmp:
image: /images/cc_by_nc_nd.png
legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
(CC BY-NC-ND 4.0)
short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 11
year: '2020'
...
---
_id: '7534'
abstract:
- lang: eng
text: 'In the past two decades, our understanding of the transition to turbulence
in shear flows with linearly stable laminar solutions has greatly improved. Regarding
the susceptibility of the laminar flow, two concepts have been particularly useful:
the edge states and the minimal seeds. In this nonlinear picture of the transition,
the basin boundary of turbulence is set by the edge state''s stable manifold and
this manifold comes closest in energy to the laminar equilibrium at the minimal
seed. We begin this paper by presenting numerical experiments in which three-dimensional
perturbations are too energetic to trigger turbulence in pipe flow but they do
lead to turbulence when their amplitude is reduced. We show that this seemingly
counterintuitive observation is in fact consistent with the fully nonlinear description
of the transition mediated by the edge state. In order to understand the physical
mechanisms behind this process, we measure the turbulent kinetic energy production
and dissipation rates as a function of the radial coordinate. Our main observation
is that the transition to turbulence relies on the energy amplification away from
the wall, as opposed to the turbulence itself, whose energy is predominantly produced
near the wall. This observation is further supported by the similar analyses on
the minimal seeds and the edge states. Furthermore, we show that the time evolution
of production-over-dissipation curves provides a clear distinction between the
different initial amplification stages of the transition to turbulence from the
minimal seed.'
article_number: '023903'
article_processing_charge: No
article_type: original
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Elena
full_name: Marensi, Elena
last_name: Marensi
- first_name: Ashley P.
full_name: Willis, Ashley P.
last_name: Willis
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Budanur NB, Marensi E, Willis AP, Hof B. Upper edge of chaos and the energetics
of transition in pipe flow. Physical Review Fluids. 2020;5(2). doi:10.1103/physrevfluids.5.023903
apa: Budanur, N. B., Marensi, E., Willis, A. P., & Hof, B. (2020). Upper edge
of chaos and the energetics of transition in pipe flow. Physical Review Fluids.
American Physical Society. https://doi.org/10.1103/physrevfluids.5.023903
chicago: Budanur, Nazmi B, Elena Marensi, Ashley P. Willis, and Björn Hof. “Upper
Edge of Chaos and the Energetics of Transition in Pipe Flow.” Physical Review
Fluids. American Physical Society, 2020. https://doi.org/10.1103/physrevfluids.5.023903.
ieee: N. B. Budanur, E. Marensi, A. P. Willis, and B. Hof, “Upper edge of chaos
and the energetics of transition in pipe flow,” Physical Review Fluids,
vol. 5, no. 2. American Physical Society, 2020.
ista: Budanur NB, Marensi E, Willis AP, Hof B. 2020. Upper edge of chaos and the
energetics of transition in pipe flow. Physical Review Fluids. 5(2), 023903.
mla: Budanur, Nazmi B., et al. “Upper Edge of Chaos and the Energetics of Transition
in Pipe Flow.” Physical Review Fluids, vol. 5, no. 2, 023903, American
Physical Society, 2020, doi:10.1103/physrevfluids.5.023903.
short: N.B. Budanur, E. Marensi, A.P. Willis, B. Hof, Physical Review Fluids 5 (2020).
date_created: 2020-02-27T10:26:57Z
date_published: 2020-02-21T00:00:00Z
date_updated: 2023-08-18T06:44:46Z
day: '21'
department:
- _id: BjHo
doi: 10.1103/physrevfluids.5.023903
external_id:
arxiv:
- '1912.09270'
isi:
- '000515065100001'
intvolume: ' 5'
isi: 1
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1912.09270
month: '02'
oa: 1
oa_version: Preprint
publication: Physical Review Fluids
publication_identifier:
issn:
- 2469-990X
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Upper edge of chaos and the energetics of transition in pipe flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 5
year: '2020'
...
---
_id: '7563'
abstract:
- lang: eng
text: "We introduce “state space persistence analysis” for deducing the symbolic
dynamics of time series data obtained from high-dimensional chaotic attractors.
To this end, we adapt a topological data analysis technique known as persistent
homology for the characterization of state space projections of chaotic trajectories
and periodic orbits. By comparing the shapes along a chaotic trajectory to those
of the periodic orbits, state space persistence analysis quantifies the shape
similarity of chaotic trajectory segments and periodic orbits. We demonstrate
the method by applying it to the three-dimensional Rössler system and a 30-dimensional
discretization of the Kuramoto–Sivashinsky partial differential equation in (1+1)
dimensions.\r\nOne way of studying chaotic attractors systematically is through
their symbolic dynamics, in which one partitions the state space into qualitatively
different regions and assigns a symbol to each such region.1–3 This yields a “coarse-grained”
state space of the system, which can then be reduced to a Markov chain encoding
all possible transitions between the states of the system. While it is possible
to obtain the symbolic dynamics of low-dimensional chaotic systems with standard
tools such as Poincaré maps, when applied to high-dimensional systems such as
turbulent flows, these tools alone are not sufficient to determine symbolic dynamics.4,5
In this paper, we develop “state space persistence analysis” and demonstrate that
it can be utilized to infer the symbolic dynamics in very high-dimensional settings."
article_number: '033109'
article_processing_charge: No
article_type: original
author:
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: Yalniz G, Budanur NB. Inferring symbolic dynamics of chaotic flows from persistence.
Chaos. 2020;30(3). doi:10.1063/1.5122969
apa: Yalniz, G., & Budanur, N. B. (2020). Inferring symbolic dynamics of chaotic
flows from persistence. Chaos. AIP Publishing. https://doi.org/10.1063/1.5122969
chicago: Yalniz, Gökhan, and Nazmi B Budanur. “Inferring Symbolic Dynamics of Chaotic
Flows from Persistence.” Chaos. AIP Publishing, 2020. https://doi.org/10.1063/1.5122969.
ieee: G. Yalniz and N. B. Budanur, “Inferring symbolic dynamics of chaotic flows
from persistence,” Chaos, vol. 30, no. 3. AIP Publishing, 2020.
ista: Yalniz G, Budanur NB. 2020. Inferring symbolic dynamics of chaotic flows from
persistence. Chaos. 30(3), 033109.
mla: Yalniz, Gökhan, and Nazmi B. Budanur. “Inferring Symbolic Dynamics of Chaotic
Flows from Persistence.” Chaos, vol. 30, no. 3, 033109, AIP Publishing,
2020, doi:10.1063/1.5122969.
short: G. Yalniz, N.B. Budanur, Chaos 30 (2020).
date_created: 2020-03-04T08:06:25Z
date_published: 2020-03-03T00:00:00Z
date_updated: 2023-08-18T06:47:16Z
day: '03'
department:
- _id: BjHo
doi: 10.1063/1.5122969
external_id:
arxiv:
- '1910.04584'
isi:
- '000519254800002'
intvolume: ' 30'
isi: 1
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1063/1.5122969
month: '03'
oa: 1
oa_version: Published Version
publication: Chaos
publication_identifier:
eissn:
- 1089-7682
issn:
- 1054-1500
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Inferring symbolic dynamics of chaotic flows from persistence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 30
year: '2020'
...
---
_id: '8043'
abstract:
- lang: eng
text: With decreasing Reynolds number, Re, turbulence in channel flow becomes spatio-temporally
intermittent and self-organises into solitary stripes oblique to the mean flow
direction. We report here the existence of localised nonlinear travelling wave
solutions of the Navier–Stokes equations possessing this obliqueness property.
Such solutions are identified numerically using edge tracking coupled with arclength
continuation. All solutions emerge in saddle-node bifurcations at values of Re
lower than the non-localised solutions. Relative periodic orbit solutions bifurcating
from branches of travelling waves have also been computed. A complete parametric
study is performed, including their stability, the investigation of their large-scale
flow, and the robustness to changes of the numerical domain.
acknowledgement: The authors thank S. Zammert and B. Budanur for useful discussions.
J. F. Gibson is gratefully acknowledged for the development and the maintenance
of the code Channelflow. Y.D. would like to thank P. Schlatter and D. S. Henningson
for an early collaboration on a similar topic in the case of plane Couette flow
during the years 2008–2013.
article_number: A7
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Chaitanya S
full_name: Paranjape, Chaitanya S
id: 3D85B7C4-F248-11E8-B48F-1D18A9856A87
last_name: Paranjape
- first_name: Yohann
full_name: Duguet, Yohann
last_name: Duguet
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Paranjape CS, Duguet Y, Hof B. Oblique stripe solutions of channel flow. Journal
of Fluid Mechanics. 2020;897. doi:10.1017/jfm.2020.322
apa: Paranjape, C. S., Duguet, Y., & Hof, B. (2020). Oblique stripe solutions
of channel flow. Journal of Fluid Mechanics. Cambridge University Press.
https://doi.org/10.1017/jfm.2020.322
chicago: Paranjape, Chaitanya S, Yohann Duguet, and Björn Hof. “Oblique Stripe Solutions
of Channel Flow.” Journal of Fluid Mechanics. Cambridge University Press,
2020. https://doi.org/10.1017/jfm.2020.322.
ieee: C. S. Paranjape, Y. Duguet, and B. Hof, “Oblique stripe solutions of channel
flow,” Journal of Fluid Mechanics, vol. 897. Cambridge University Press,
2020.
ista: Paranjape CS, Duguet Y, Hof B. 2020. Oblique stripe solutions of channel flow.
Journal of Fluid Mechanics. 897, A7.
mla: Paranjape, Chaitanya S., et al. “Oblique Stripe Solutions of Channel Flow.”
Journal of Fluid Mechanics, vol. 897, A7, Cambridge University Press, 2020,
doi:10.1017/jfm.2020.322.
short: C.S. Paranjape, Y. Duguet, B. Hof, Journal of Fluid Mechanics 897 (2020).
date_created: 2020-06-29T07:59:35Z
date_published: 2020-08-25T00:00:00Z
date_updated: 2023-08-22T07:48:02Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2020.322
external_id:
isi:
- '000539132300001'
file:
- access_level: open_access
checksum: 3f487bf6d9286787096306eaa18702e8
content_type: application/pdf
creator: cziletti
date_created: 2020-06-30T08:37:37Z
date_updated: 2020-07-14T12:48:08Z
file_id: '8070'
file_name: 2020_JournalOfFluidMech_Paranjape.pdf
file_size: 767873
relation: main_file
file_date_updated: 2020-07-14T12:48:08Z
has_accepted_license: '1'
intvolume: ' 897'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '08'
oa: 1
oa_version: Published Version
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- '14697645'
issn:
- '00221120'
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Oblique stripe solutions of channel flow
tmp:
image: /images/cc_by_nc_sa.png
legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
BY-NC-SA 4.0)
short: CC BY-NC-SA (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 897
year: '2020'
...
---
_id: '8634'
abstract:
- lang: eng
text: In laboratory studies and numerical simulations, we observe clear signatures
of unstable time-periodic solutions in a moderately turbulent quasi-two-dimensional
flow. We validate the dynamical relevance of such solutions by demonstrating that
turbulent flows in both experiment and numerics transiently display time-periodic
dynamics when they shadow unstable periodic orbits (UPOs). We show that UPOs we
computed are also statistically significant, with turbulent flows spending a sizable
fraction of the total time near these solutions. As a result, the average rates
of energy input and dissipation for the turbulent flow and frequently visited
UPOs differ only by a few percent.
acknowledgement: M. F. S. and R. O. G. acknowledge funding from the National Science
Foundation (CMMI-1234436, DMS1125302, CMMI-1725587) and Defense Advanced Research
Projects Agency (HR0011-16-2-0033). B. S.has received funding from the People Programme
(Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007–2013/
under REA Grant Agreement No. 291734.
article_number: '064501'
article_processing_charge: No
article_type: original
author:
- first_name: Balachandra
full_name: Suri, Balachandra
id: 47A5E706-F248-11E8-B48F-1D18A9856A87
last_name: Suri
- first_name: Logan
full_name: Kageorge, Logan
last_name: Kageorge
- first_name: Roman O.
full_name: Grigoriev, Roman O.
last_name: Grigoriev
- first_name: Michael F.
full_name: Schatz, Michael F.
last_name: Schatz
citation:
ama: Suri B, Kageorge L, Grigoriev RO, Schatz MF. Capturing turbulent dynamics and
statistics in experiments with unstable periodic orbits. Physical Review Letters.
2020;125(6). doi:10.1103/physrevlett.125.064501
apa: Suri, B., Kageorge, L., Grigoriev, R. O., & Schatz, M. F. (2020). Capturing
turbulent dynamics and statistics in experiments with unstable periodic orbits.
Physical Review Letters. American Physical Society. https://doi.org/10.1103/physrevlett.125.064501
chicago: Suri, Balachandra, Logan Kageorge, Roman O. Grigoriev, and Michael F. Schatz.
“Capturing Turbulent Dynamics and Statistics in Experiments with Unstable Periodic
Orbits.” Physical Review Letters. American Physical Society, 2020. https://doi.org/10.1103/physrevlett.125.064501.
ieee: B. Suri, L. Kageorge, R. O. Grigoriev, and M. F. Schatz, “Capturing turbulent
dynamics and statistics in experiments with unstable periodic orbits,” Physical
Review Letters, vol. 125, no. 6. American Physical Society, 2020.
ista: Suri B, Kageorge L, Grigoriev RO, Schatz MF. 2020. Capturing turbulent dynamics
and statistics in experiments with unstable periodic orbits. Physical Review Letters.
125(6), 064501.
mla: Suri, Balachandra, et al. “Capturing Turbulent Dynamics and Statistics in Experiments
with Unstable Periodic Orbits.” Physical Review Letters, vol. 125, no.
6, 064501, American Physical Society, 2020, doi:10.1103/physrevlett.125.064501.
short: B. Suri, L. Kageorge, R.O. Grigoriev, M.F. Schatz, Physical Review Letters
125 (2020).
date_created: 2020-10-08T17:27:32Z
date_published: 2020-08-05T00:00:00Z
date_updated: 2023-09-05T12:08:29Z
day: '05'
department:
- _id: BjHo
doi: 10.1103/physrevlett.125.064501
ec_funded: 1
external_id:
arxiv:
- '2008.02367'
isi:
- '000555785600005'
intvolume: ' 125'
isi: 1
issue: '6'
keyword:
- General Physics and Astronomy
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2008.02367
month: '08'
oa: 1
oa_version: Preprint
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '291734'
name: International IST Postdoc Fellowship Programme
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Capturing turbulent dynamics and statistics in experiments with unstable periodic
orbits
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 125
year: '2020'
...
---
_id: '7932'
abstract:
- lang: eng
text: Pulsating flows through tubular geometries are laminar provided that velocities
are moderate. This in particular is also believed to apply to cardiovascular flows
where inertial forces are typically too low to sustain turbulence. On the other
hand, flow instabilities and fluctuating shear stresses are held responsible for
a variety of cardiovascular diseases. Here we report a nonlinear instability mechanism
for pulsating pipe flow that gives rise to bursts of turbulence at low flow rates.
Geometrical distortions of small, yet finite, amplitude are found to excite a
state consisting of helical vortices during flow deceleration. The resulting flow
pattern grows rapidly in magnitude, breaks down into turbulence, and eventually
returns to laminar when the flow accelerates. This scenario causes shear stress
fluctuations and flow reversal during each pulsation cycle. Such unsteady conditions
can adversely affect blood vessels and have been shown to promote inflammation
and dysfunction of the shear stress-sensitive endothelial cell layer.
article_processing_charge: No
article_type: original
author:
- first_name: Duo
full_name: Xu, Duo
id: 3454D55E-F248-11E8-B48F-1D18A9856A87
last_name: Xu
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Xingyu
full_name: Ma, Xingyu
id: 34BADBA6-F248-11E8-B48F-1D18A9856A87
last_name: Ma
orcid: 0000-0002-0179-9737
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Xu D, Varshney A, Ma X, et al. Nonlinear hydrodynamic instability and turbulence
in pulsatile flow. Proceedings of the National Academy of Sciences of the United
States of America. 2020;117(21):11233-11239. doi:10.1073/pnas.1913716117
apa: Xu, D., Varshney, A., Ma, X., Song, B., Riedl, M., Avila, M., & Hof, B.
(2020). Nonlinear hydrodynamic instability and turbulence in pulsatile flow. Proceedings
of the National Academy of Sciences of the United States of America. National
Academy of Sciences. https://doi.org/10.1073/pnas.1913716117
chicago: Xu, Duo, Atul Varshney, Xingyu Ma, Baofang Song, Michael Riedl, Marc Avila,
and Björn Hof. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
Flow.” Proceedings of the National Academy of Sciences of the United States
of America. National Academy of Sciences, 2020. https://doi.org/10.1073/pnas.1913716117.
ieee: D. Xu et al., “Nonlinear hydrodynamic instability and turbulence in
pulsatile flow,” Proceedings of the National Academy of Sciences of the United
States of America, vol. 117, no. 21. National Academy of Sciences, pp. 11233–11239,
2020.
ista: Xu D, Varshney A, Ma X, Song B, Riedl M, Avila M, Hof B. 2020. Nonlinear hydrodynamic
instability and turbulence in pulsatile flow. Proceedings of the National Academy
of Sciences of the United States of America. 117(21), 11233–11239.
mla: Xu, Duo, et al. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
Flow.” Proceedings of the National Academy of Sciences of the United States
of America, vol. 117, no. 21, National Academy of Sciences, 2020, pp. 11233–39,
doi:10.1073/pnas.1913716117.
short: D. Xu, A. Varshney, X. Ma, B. Song, M. Riedl, M. Avila, B. Hof, Proceedings
of the National Academy of Sciences of the United States of America 117 (2020)
11233–11239.
date_created: 2020-06-07T22:00:51Z
date_published: 2020-05-26T00:00:00Z
date_updated: 2023-11-30T10:55:13Z
day: '26'
department:
- _id: BjHo
doi: 10.1073/pnas.1913716117
ec_funded: 1
external_id:
arxiv:
- '2005.11190'
isi:
- '000536797100014'
intvolume: ' 117'
isi: 1
issue: '21'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2005.11190
month: '05'
oa: 1
oa_version: Preprint
page: 11233-11239
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: I04188
name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Proceedings of the National Academy of Sciences of the United States
of America
publication_identifier:
eissn:
- '10916490'
issn:
- '00278424'
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
related_material:
link:
- description: News on IST Homepage
relation: press_release
url: https://ist.ac.at/en/news/blood-flows-more-turbulent-than-previously-expected/
record:
- id: '12726'
relation: dissertation_contains
status: public
- id: '14530'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Nonlinear hydrodynamic instability and turbulence in pulsatile flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 117
year: '2020'
...
---
_id: '7258'
abstract:
- lang: eng
text: Many flows encountered in nature and applications are characterized by a chaotic
motion known as turbulence. Turbulent flows generate intense friction with pipe
walls and are responsible for considerable amounts of energy losses at world scale.
The nature of turbulent friction and techniques aimed at reducing it have been
subject of extensive research over the last century, but no definite answer has
been found yet. In this thesis we show that in pipes at moderate turbulent Reynolds
numbers friction is better described by the power law first introduced by Blasius
and not by the Prandtl–von Kármán formula. At higher Reynolds numbers, large scale
motions gradually become more important in the flow and can be related to the
change in scaling of friction. Next, we present a series of new techniques that
can relaminarize turbulence by suppressing a key mechanism that regenerates it
at walls, the lift–up effect. In addition, we investigate the process of turbulence
decay in several experiments and discuss the drag reduction potential. Finally,
we examine the behavior of friction under pulsating conditions inspired by the
human heart cycle and we show that under such circumstances turbulent friction
can be reduced to produce energy savings.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
citation:
ama: Scarselli D. New approaches to reduce friction in turbulent pipe flow. 2020.
doi:10.15479/AT:ISTA:7258
apa: Scarselli, D. (2020). New approaches to reduce friction in turbulent pipe
flow. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:7258
chicago: Scarselli, Davide. “New Approaches to Reduce Friction in Turbulent Pipe
Flow.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:7258.
ieee: D. Scarselli, “New approaches to reduce friction in turbulent pipe flow,”
Institute of Science and Technology Austria, 2020.
ista: Scarselli D. 2020. New approaches to reduce friction in turbulent pipe flow.
Institute of Science and Technology Austria.
mla: Scarselli, Davide. New Approaches to Reduce Friction in Turbulent Pipe Flow.
Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:7258.
short: D. Scarselli, New Approaches to Reduce Friction in Turbulent Pipe Flow, Institute
of Science and Technology Austria, 2020.
date_created: 2020-01-12T16:07:26Z
date_published: 2020-01-13T00:00:00Z
date_updated: 2023-09-15T12:20:08Z
day: '13'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: BjHo
doi: 10.15479/AT:ISTA:7258
ec_funded: 1
file:
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checksum: 4df1ab24e9896635106adde5a54615bf
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creator: dscarsel
date_created: 2020-01-12T15:57:14Z
date_updated: 2021-01-13T23:30:05Z
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file_name: 2020_Scarselli_Thesis.zip
file_size: 26640830
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date_updated: 2021-01-13T23:30:05Z
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file_date_updated: 2021-01-13T23:30:05Z
has_accepted_license: '1'
language:
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month: '01'
oa: 1
oa_version: None
page: '174'
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
- _id: 25136C54-B435-11E9-9278-68D0E5697425
grant_number: HO 4393/1-2
name: Experimental studies of the turbulence transition and transport processes
in turbulent Taylor-Couette currents
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '6228'
relation: part_of_dissertation
status: public
- id: '6486'
relation: part_of_dissertation
status: public
- id: '461'
relation: part_of_dissertation
status: public
- id: '422'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: New approaches to reduce friction in turbulent pipe flow
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '8350'
abstract:
- lang: eng
text: "Cytoplasm is a gel-like crowded environment composed of tens of thousands
of macromolecules, organelles, cytoskeletal networks and cytosol. The structure
of the cytoplasm is thought to be highly organized and heterogeneous due to the
crowding of its constituents and their effective compartmentalization. In such
an environment, the diffusive dynamics of the molecules is very restricted, an
effect that is further amplified by clustering and anchoring of molecules. Despite
the jammed nature of the cytoplasm at the microscopic scale, large-scale reorganization
of cytoplasm is essential for important cellular functions, such as nuclear positioning
and cell division. How such mesoscale reorganization of the cytoplasm is achieved,
especially for very large cells such as oocytes or syncytial tissues that can
span hundreds of micrometers in size, has only begun to be understood.\r\nIn this
thesis, I focus on the recent advances in elucidating the molecular, cellular
and biophysical principles underlying cytoplasmic organization across different
scales, structures and species. First, I outline which of these principles have
been identified by reductionist approaches, such as in vitro reconstitution assays,
where boundary conditions and components can be modulated at ease. I then describe
how the theoretical and experimental framework established in these reduced systems
have been applied to their more complex in vivo counterparts, in particular oocytes
and embryonic syncytial structures, and discuss how such complex biological systems
can initiate symmetry breaking and establish patterning.\r\nSpecifically, I examine
an example of large-scale reorganizations taking place in zebrafish embryos, where
extensive cytoplasmic streaming leads to the segregation of cytoplasm from yolk
granules along the animal-vegetal axis of the embryo. Using biophysical experimentation
and theory, I investigate the forces underlying this process, to show that this
process does not rely on cortical actin reorganization, as previously thought,
but instead on a cell-cycle-dependent bulk actin polymerization wave traveling
from the animal to the vegetal pole of the embryo. This wave functions in segregation
by both pulling cytoplasm animally and pushing yolk granules vegetally. Cytoplasm
pulling is mediated by bulk actin network flows exerting friction forces on the
cytoplasm, while yolk granule pushing is achieved by a mechanism closely resembling
actin comet formation on yolk granules. This study defines a novel role of bulk
actin polymerization waves in embryo polarization via cytoplasmic segregation.
Lastly, I describe the cytoplasmic reorganizations taking place during zebrafish
oocyte maturation, where the initial segregation of the cytoplasm and yolk granules
occurs. Here, I demonstrate a previously uncharacterized wave of microtubule aster
formation, traveling the oocyte along the animal-vegetal axis. Further research
is required to determine the role of such microtubule structures in cytoplasmic
reorganizations therein.\r\nCollectively, these studies provide further evidence
for the coupling between cell cytoskeleton and cell cycle machinery, which can
underlie a core self-organizing mechanism for orchestrating large-scale reorganizations
in a cell-cycle-tunable manner, where the modulations of the force-generating
machinery and cytoplasmic mechanics can be harbored to fulfill cellular functions."
acknowledged_ssus:
- _id: PreCl
- _id: Bio
- _id: EM-Fac
acknowledgement: "I would have had no fish and hence no results without our wonderful
fish facility crew, Verena Mayer, Eva Schlegl, Andreas Mlak and Matthias Nowak.
Special thanks to Verena for being always happy to help and dealing with our chaotic
schedules in the lab. Danke auch, Verena, für deine Geduld, mit mir auf Deutsch
zu sprechen. Das hat mir sehr geholfen.\r\nSpecial thanks to the Bioimaging and
EM facilities at IST Austria for supporting us every day. Very special thanks would
go to Robert Hauschild for his continuous support on data analysis and also to Jack
Merrin for designing and building microfabricated chambers for the project and for
the various discussions on making zebrafish extracts."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Shayan
full_name: Shamipour, Shayan
id: 40B34FE2-F248-11E8-B48F-1D18A9856A87
last_name: Shamipour
citation:
ama: Shamipour S. Bulk actin dynamics drive phase segregation in zebrafish oocytes
. 2020. doi:10.15479/AT:ISTA:8350
apa: Shamipour, S. (2020). Bulk actin dynamics drive phase segregation in zebrafish
oocytes . Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:8350
chicago: Shamipour, Shayan. “Bulk Actin Dynamics Drive Phase Segregation in Zebrafish
Oocytes .” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:8350.
ieee: S. Shamipour, “Bulk actin dynamics drive phase segregation in zebrafish oocytes
,” Institute of Science and Technology Austria, 2020.
ista: Shamipour S. 2020. Bulk actin dynamics drive phase segregation in zebrafish
oocytes . Institute of Science and Technology Austria.
mla: Shamipour, Shayan. Bulk Actin Dynamics Drive Phase Segregation in Zebrafish
Oocytes . Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:8350.
short: S. Shamipour, Bulk Actin Dynamics Drive Phase Segregation in Zebrafish Oocytes
, Institute of Science and Technology Austria, 2020.
date_created: 2020-09-09T11:12:10Z
date_published: 2020-09-09T00:00:00Z
date_updated: 2023-09-27T14:16:45Z
day: '09'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: BjHo
- _id: CaHe
doi: 10.15479/AT:ISTA:8350
file:
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checksum: 6e47871c74f85008b9876112eb3fcfa1
content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
creator: sshamip
date_created: 2020-09-09T11:06:27Z
date_updated: 2021-09-11T22:30:05Z
embargo_to: open_access
file_id: '8351'
file_name: Shayan-Thesis-Final.docx
file_size: 65194814
relation: source_file
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checksum: 1b44c57f04d7e8a6fe41b1c9c55a52a3
content_type: application/pdf
creator: sshamip
date_created: 2020-09-09T11:06:13Z
date_updated: 2021-09-11T22:30:05Z
embargo: 2021-09-10
file_id: '8352'
file_name: Shayan-Thesis-Final.pdf
file_size: 23729605
relation: main_file
file_date_updated: 2021-09-11T22:30:05Z
has_accepted_license: '1'
language:
- iso: eng
month: '09'
oa: 1
oa_version: None
page: '107'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '661'
relation: part_of_dissertation
status: public
- id: '6508'
relation: part_of_dissertation
status: public
- id: '7001'
relation: part_of_dissertation
status: public
- id: '735'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Carl-Philipp J
full_name: Heisenberg, Carl-Philipp J
id: 39427864-F248-11E8-B48F-1D18A9856A87
last_name: Heisenberg
orcid: 0000-0002-0912-4566
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: 'Bulk actin dynamics drive phase segregation in zebrafish oocytes '
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...