Academic Interests
Physics of complex systems in geology and biology. Currently my projects focus mostly on biology.
I mainly develop and use high resolution in situ time-lapse imaging methods and specialized analysis of the images and processes studied.
Teaching and student engagement
Possible master projects:
Student bio-makerspace: LagLivLab
Higher education and employment history
Siv.Ing. Physics NTH 1991, Dr.Ing. Physical chemistry, NTH 1995, PostDoc Physical chemistry Universite Paris-Sud 1995-1998, PostDoc Department of Physics, UiO 1998-2003, Senior researcher 2003-2006 PGP, UiO. 2006- Professor, Deptartment of Physics, UiO
Publications
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Combriat, Thomas Michel Daniel; Olsen, Petter Angell; Låstad, Silja Borring; Malthe-Sørenssen, Anders; Krauss, Stefan Johannes Karl & Dysthe, Dag Kristian
(2024).
Acoustic Wave-Induced Stroboscopic Optical Mechanotyping of Adherent Cells.
Advanced Science.
ISSN 2198-3844.
doi:
10.1002/advs.202307929.
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Li, Lei; Kohler, Felix; Dziadkowiec, Joanna; Røyne, Anja; Espinosa Marzal, Rosa M. & Bresme, Fernando
[Show all 8 contributors for this article]
(2022).
Limits to Crystallization Pressure.
Langmuir.
ISSN 0743-7463.
38(37),
p. 11265–11273.
doi:
10.1021/acs.langmuir.2c01325.
Full text in Research Archive
Show summary
Crystallization pressure drives deformation and damage in monuments, buildings, and the Earth’s crust. Even though the phenomenon has been known for 170 years, there is no agreement between theoretical calculations of the maximum attainable pressure and experimentally measured pressures. We have therefore developed a novel experimental technique to image the nanoconfined crystallization process while controlling the pressure and applied it to calcite. The results show that displacement by crystallization pressure is arrested at pressures well below the thermodynamic limit. We use existing molecular dynamics simulations and atomic force microscopy data to construct a robust model of the disjoining pressure in this system and thereby calculate the absolute distance between the surfaces. On the basis of the high-resolution experiments and modeling, we formulate a novel mechanism for the transition between damage and adhesion by crystallization that may find application in Earth and materials sciences and in conservation of cultural heritage.
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Gløersen, Øyvind Nøstdahl; Colosio, Alessandro L.; Boone, Jan; Dysthe, Dag Kristian; Malthe-Sørenssen, Anders & Capelli, Carlo
[Show all 7 contributors for this article]
(2022).
Modeling V̇o2 on-kinetics based on intensity-dependent delayed adjustment and loss of efficiency (DALE).
Journal of applied physiology.
ISSN 8750-7587.
132(6),
p. 1480–1488.
doi:
10.1152/japplphysiol.00570.2021.
Full text in Research Archive
Show summary
This study presents and evaluates a new mathematical model of V̇o2 on-kinetics, with the following properties: 1) a progressively slower primary phase following the size-principle of motor unit recruitment, explaining the delayed V̇o2 steady state seen in the heavy exercise intensity domain, and 2) a severe-domain slow component modeled as a time-dependent decrease in efficiency. Breath-by-breath V̇o2 measurements from eight subjects performing step cycling transitions, in the moderate, heavy, and severe exercise domains, were fitted to the conventional three-phase model and the new model. Model performance was evaluated with a residual analysis and by comparing Bayesian (BIC) and corrected Akaike (AICc) information criteria. The residual analysis showed no systematic deviations, except perhaps for the initial part of the primary phase. BIC favored the new model, being 9.3 (SD 7.1) lower than the conventional model whereas AICc was similar between models. Compared with the conventional three-phase model, the proposed model distinguishes between the kinetic adaptations in the heavy and severe domains by predicting a delayed steady-state V̇o2 in the heavy and no steady-state V̇o2 in the severe domain. This allows to determine when stable oxygen costs of exercise are attainable and it also represents a first step in defining time-dependent oxygen costs when stable energy conversion efficiency is not attainable.
NEW & NOTEWORTHY: We propose and assess a new minimalistic integrated model for the V̇o2 on-kinetics, inspired by the currently available best evidence of the underlying mechanisms. We show that the model provides a similar fit as the conventionally used three-phase model, even though a stricter data fitting method is used for the proposed model. The proposed model clarifies misconceptions related to the V̇o2 slow component’s behavior, by clearly predicting that steady-state V̇o2 is attainable in the moderate and heavy exercise intensity domains. Furthermore, the model opens new possibilities for assessing oxygen cost during severe intensity exercise without the fallible assumption of time-constant energy-conversion efficiency.
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de Ruiter, Lisa; Gunnæs, Anette Eleonora; Dysthe, Dag Kristian & Austrheim, Håkon Olaf
(2021).
Quartz dissolution associated with magnesium silicate hydrate cement precipitation.
Solid Earth (SE).
ISSN 1869-9510.
12(2),
p. 389–404.
doi:
10.5194/se-12-389-2021.
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Høgberget, Jørgen; Dysthe, Dag Kristian & Jettestuen, Espen
(2020).
Direct Coupling of Free Diffusion Models to Microscopic Models of Confined Crystal Growth and Dissolution.
arXiv.org.
ISSN 2331-8422.
Show summary
We couple a free solute diffusion model to a model of crystal surface growth represented by, but not limited to, a (2 + 1)-dimensional solid-on-solid (SOS) model confined by a flat surface. We use kinetic Monte Carlo (KMC) with dissolution rates based on nearest-neighbor interactions to solve the Master equation for the surface dynamics, and we use an offlattice random walk to model the Fickian diffusion of the solute particles. The two solvers are coupled directly through deposition rates of the free particles calculated using the mean first passage time (MFPT) of deposition that is found to scale as r−4. Two variants are studied: ignoring (radial) and not ignoring the line of sight (pathfinding). Reference models such as uniform concentration (random deposition) and lattice diffusion (crystal lattice extended into the liquid) are used for comparison. We find that the macroscopic limit of the surface dynamics is reproduced by all models. The free diffusion models produce a lower equilibrium roughness and a smaller height autocorrelation length than the reference models, and are found to behave very well in tight confinements. It is also demonstrated that lattice diffusion does not work well in tight confinements. The two MFPT models behave very similarly close to equilibrium and for dissolution, but becomes increasingly different with increasing surface growth speed. The model is put to use by simulating a cavity with a flux boundary condition at one side. The conclusion is that the new model excels in confinement, and line of sight can in practice be ignored since the dominant deposition sites likely are in line of sight, which minimizes the CPU-time needed in the coupling.
View all works in Cristin
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Vogt, Yngve; Krauss, Stefan Johannes Karl; Mossige, Joachim; Dysthe, Dag Kristian; Angheluta, Luiza & Jensenius, Alexander Refsum
(2023).
Bereder grunnen for kunstige organer.
[Business/trade/industry journal].
Apollon.
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Dziadkowiec, Joanna; Zareeipolgardani, Bahareh; Cheng, Hsiu-Wei; Dysthe, Dag Kristian; Røyne, Anja & Valtiner, Markus
(2021).
Forces between reactive surfaces.
Show summary
Adhesive and repulsive, nm-range surface forces acting between mineral grains control colloidal stability and mineral aggregation but less is known about how these forces are affected by surface reactivity and to what extent these grain-scale forces can influence various deformation processes in rocks. In this experimental work, we explore and quantify the surface forces acting between dynamic mineral surfaces that undergo recrystallization or are chemically reactive in contact with water or aqueous salt solutions. Our experimental setup consists of the surface forces apparatus (SFA) coupled with the multiple beam interferometry (MBI). This setup can excellently reproduce a typical grain contact geometry with nanometer-thin water films confined between contacting mineral grains over relatively large, micron-sized contact areas. Owing to the use of MBI, both surface growth or dissolution processes can be monitored during force measurements in real-time. As such, SFA can provide information about the links between surface reactivity and adhesive or repulsive surface forces. Using the examples of force measurements between recrystallizing or chemically reactive mineral surfaces such as carbonates, hydroxides, and silicates, we comment on the relationship between the measured surface forces and surface reactivity. We link our findings with the observed changes in mineral phases, surface topographies, or surface roughness. We also comment on how the micron-scale confinement in the SFA affects the growth and dissolution processes in contrast to less confined regions. The magnitude of the forces associated with dynamic mineral surfaces and the potential significance of these forces to macroscopic deformation processes and cohesion in rocks are discussed.
View all works in Cristin
Published
Nov. 29, 2010 10:50 AM
- Last modified
Feb. 1, 2023 11:34 AM