Anders Malthe-Sørenssen

• 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.
• Ye, Bo; Jettestuen, Espen & Malthe-Sørenssen, Anders (2023). A node-splitting lattice spring model coupled with a J-integral formulation as a fracture criterion. International Journal of Fracture. ISSN 0376-9429. p. 1–19. doi: 10.1007/s10704-023-00749-0. Full text in Research Archive Show summary

  A global energy minimization criterion based on Griffith’s theory is introduced for the node-splitting lattice spring model. The fracture criterion is computed by both direct numerical simulations of energy release rate G and through a J-integral formulation for comparison and validation. For mode I fractures, the standard implementation of J-integral formulation yields very good estimations of the energy release rate, but for mixed mode fracture the estimations deviates from the direct calculated energy release rate. The reasons for this discrepancy are elucidated and an approach to best approximate the J value is given. This method is compared with the more standard maximum tip stress threshold crack criterion, and shows a much better prediction of the energy release rate and is more robust under grid refinement.

• Schøyen, Vemund Sigmundson; Pettersen, Markus Borud; Holzhausen, Konstantin; Fyhn, Marianne; Malthe-Sørenssen, Anders & Lepperød, Mikkel Elle (2023). Coherently remapping toroidal cells but not Grid cells are responsible for path integration in virtual agents. iScience. ISSN 2589-0042. 26(11), p. 1–17. doi: 10.1016/j.isci.2023.108102. Full text in Research Archive
• Najafi, Fahimeh; Sveinsson, Henrik Andersen; Dreierstad, Christer; Glad, Hans Erlend Bakken & Malthe-Sørenssen, Anders (2023). Modeling the relationship between mechanical yield stress and material geometry using convolutional neural networks. Applied Physics Letters. ISSN 0003-6951. 123(11). doi: 10.1063/5.0160338. Full text in Research Archive
• Nordhagen, Even Marius; Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2023). Diffusion-Driven Frictional Aging in Silicon Carbide. Tribology letter. ISSN 1023-8883. 71(3), p. 1–11. doi: 10.1007/s11249-023-01762-z. Full text in Research Archive
• Hanssen, Kine Ødegård & Malthe-Sørenssen, Anders (2022). Perineuronal nets restrict transport near the neuron surface: A coarse-grained molecular dynamics study. Frontiers in Computational Neuroscience. ISSN 1662-5188. 16. doi: 10.3389/fncom.2022.967735. Full text in Research Archive
• Guren, Marthe Grønlie; Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders & Renard, Francois (2022). Nanoscale Damage Production by Dynamic Tensile Rupture in α-Quartz. Geophysical Research Letters. ISSN 0094-8276. 49(20). doi: 10.1029/2022GL100468. Full text in Research Archive
• Odden, Tor Ole Bigton; Silvia, Devin W. & Malthe-Sørenssen, Anders (2022). Using computational essays to foster disciplinary epistemic agency in undergraduate science. Journal of Research in Science Teaching. ISSN 0022-4308. 60(5), p. 937–977. doi: 10.1002/tea.21821. Full text in Research Archive
• 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.

• Malthe-Sørenssen, Anders (2021). The onset of a slip. Nature Physics. ISSN 1745-2473. 17(9), p. 983–985. doi: 10.1038/s41567-021-01312-1.
• Sveinsson, Henrik Andersen; Ning, Fulong; Cao, Pinqiang; Fang, Bin & Malthe-Sørenssen, Anders (2021). Grain-Size-Governed Shear Failure Mechanism of Polycrystalline Methane Hydrates. Journal of Physical Chemistry C. ISSN 1932-7447. 125(18), p. 10034–10042. doi: 10.1021/acs.jpcc.1c00901. Full text in Research Archive
• Guren, Marthe Grønlie; Sveinsson, Henrik Andersen; Hafreager, Anders; Jamtveit, Bjørn; Malthe-Sørenssen, Anders & Renard, Francois (2021). Molecular dynamics study of confined water in the periclase-brucite system under conditions of reaction-induced fracturing. Geochimica et Cosmochimica Acta. ISSN 0016-7037. 294, p. 13–27. doi: 10.1016/j.gca.2020.11.016. Full text in Research Archive
• Odden, Tor Ole & Malthe-Sørenssen, Anders (2020). Using computational essays to scaffold professional physics practice. European Journal of Physics. ISSN 0143-0807. 42(015701). doi: 10.1088/1361-6404/abb8b7. Full text in Research Archive
• Hansson, Kenth-Arne; Eftestøl, Einar; Bruusgaard, Jo C.; Juvkam, Inga; Cramer, Alyssa W. & Malthe-Sørenssen, Anders [Show all 8 contributors for this article] (2020). Myonuclear content regulates cell size with similar scaling properties in mice and humans. Nature Communications. ISSN 2041-1723. 11(1). doi: 10.1038/s41467-020-20057-8. Full text in Research Archive
• Lepperød, Mikkel Elle; Dragly, Svenn-Arne; Buccino, Alessio Paolo; Mobarhan, Milad; Malthe-Sørenssen, Anders & Hafting, Torkel [Show all 7 contributors for this article] (2020). Experimental Pipeline (Expipe): A Lightweight Data Management Platform to Simplify the Steps From Experiment to Data Analysis. Frontiers in Neuroinformatics. ISSN 1662-5196. 14. doi: 10.3389/fninf.2020.00030. Full text in Research Archive Show summary

  As experimental neuroscience is moving toward more integrative approaches, with a variety of acquisition techniques covering multiple spatiotemporal scales, data management is becoming increasingly challenging for neuroscience laboratories. Often, datasets are too large to practically be stored on a laptop or a workstation. The ability to query metadata collections without retrieving complete datasets is therefore critical to efficiently perform new analyses and explore the data. At the same time, new experimental paradigms lead to constantly changing specifications for the metadata to be stored. Despite this, there is currently a serious lack of agile software tools for data management in neuroscience laboratories. To meet this need, we have developed Expipe, a lightweight data management framework that simplifies the steps from experiment to data analysis. Expipe provides the functionality to store and organize experimental data and metadata for easy retrieval in exploration and analysis throughout the experimental pipeline. It is flexible in terms of defining the metadata to store and aims to solve the storage and retrieval challenges of data/metadata due to ever changing experimental pipelines. Due to its simplicity and lightweight design, we envision Expipe as an easy-to-use data management solution for experimental laboratories, that can improve provenance, reproducibility, and sharing of scientific projects.

• Sveinsson, Henrik Andersen; Hafreager, Anders; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya & Malthe-Sørenssen, Anders (2020). Direct Atomic Simulations of Facet Formation and Equilibrium Shapes of SiC Nanoparticles. Crystal Growth & Design. ISSN 1528-7483. 20(4), p. 2147–2152. doi: 10.1021/acs.cgd.9b00612. Full text in Research Archive Show summary

  Understanding the shapes of nanoparticles is an important interdisciplinary problem because particle shapes can affect their properties, functionality, and applications. Advances in nanoscale imaging probes have revealed exquisite details of nanofaceting phenomena. However, quantitative theoretical predictions have not kept up the pace with experimental advances, and the atomic pathways of facet formation are largely unknown due to a lack of direct observations and simulations. Here we examine facet formation in spherical and cubic SiC nanoparticles and in SiC nanowires using molecular dynamics simulations reaching microseconds. We characterize layer-by-layer formation, diffusional motion along edges and corners, and determine energy barriers. We find that the equilibrium shapes are identical regardless of the initial shape of SiC nanoparticles or nanowires. For spherical and cubic nanoparticles, (110) facets form within 10 ns by lateral liquid-like diffusion of atoms. In contrast, faceting in SiC nanowires also involves normal diffusional motion with a higher energy barrier and hence much longer faceting times. These results have important implications for molecular-level understanding of the synthesis and stability of ceramic nanocrystals and nanowires.

• Gløersen, Øyvind Nøstdahl; Gilgien, Matthias; Dysthe, Dag Kristian; Malthe-Sørenssen, Anders & Losnegard, Thomas Johansen (2020). Oxygen Demand, Uptake, and Deficits in Elite Cross-country Skiers during a 15-km Race. Medicine & Science in Sports & Exercise. ISSN 0195-9131. 52(4), p. 983–992. doi: 10.1249/MSS.0000000000002209. Full text in Research Archive Show summary

  Purpose: To quantify the repeated oxygen deficits attained during intermittent endurance exercise by measuring oxygen consumption (V[Combining Dot Above]O2) and oxygen demand (V[Combining Dot Above]O2dem) throughout a simulated roller ski race. Methods: Eight male elite cross-country skiers (V[Combining Dot Above]O2,peak 77.4 ± 4.4 mL·min-1·kg-1) raced a 13.5 km roller ski time-trial on a World Cup course. On two additional days, athletes completed (i) 6 sub-maximal loads (à 5 min) and a ~ 4 min maximal trial to establish athlete-specific estimates of skiing economy, V[Combining Dot Above]O2,peak, and maximal ΣO2def (MAOD); and (ii) a simulation of the time-trial on a roller skiing treadmill. During the simulation, external work rate (Pprop) and skiing speed (v) were adjusted to match the Pprop and v measured during the time-trial, and pulmonary V[Combining Dot Above]O2 was measured breath-by-breath. V[Combining Dot Above]O2dem and ΣO2def were calculated using an athlete-specific model for skiing economy throughout the treadmill simulation. Results: During the treadmill simulation V[Combining Dot Above]O2 was on average 0.77V[Combining Dot Above]O2,peak, and active V[Combining Dot Above]O2dem, (i.e., excluding the time in simulated downhills), was on average 1.01V[Combining Dot Above]O2,peak. The athletes repeatedly attained substantial oxygen deficits in individual uphill sections of the treadmill simulation, but the deficits were typically small compared to their MAOD (average 14%, range ~0-50%). However, the ΣO2def summed over all periods of active propulsion was on average 3.8MAOD. Conclusion: Athletes repeatedly attain substantial oxygen deficits in the uphill segments of a distance cross-country ski race. Furthermore, the total accumulated oxygen deficit of all these segments is several times higher than the athletes’ MAODs. This suggests that rapid recovery of the energy stores represented by the oxygen deficit is necessary during downhill sections, and that this might be an important determinant of distance skiing performance.

• Thøgersen, Kjetil; Sveinsson, Henrik Andersen; Scheibert, Julien; Renard, Francois & Malthe-Sørenssen, Anders (2019). The Moment Duration Scaling Relation for Slow Rupture Arises From Transient Rupture Speeds. Geophysical Research Letters. ISSN 0094-8276. 46(22), p. 12805–12814. doi: 10.1029/2019GL084436. Full text in Research Archive
• Thøgersen, Kjetil; Sveinsson, Henrik Andersen; Amundsen, David Skålid; Scheibert, Julien; Renard, Francois & Malthe-Sørenssen, Anders (2019). Minimal model for slow, sub-Rayleigh, supershear, and unsteady rupture propagation along homogeneously loaded frictional interfaces. Physical Review E (PRE). ISSN 2470-0045. 100(4). doi: 10.1103/PhysRevE.100.043004. Full text in Research Archive
• Thøgersen, Kjetil; Gilbert, Adrien; Schuler, Thomas & Malthe-Sørenssen, Anders (2019). Rate-and-state friction explains glacier surge propagation. Nature Communications. ISSN 2041-1723. 10(1). doi: 10.1038/s41467-019-10506-4. Full text in Research Archive
• Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2019). Molecular-scale thermally activated fractures in methane hydrates: a molecular dynamics study. Physical Chemistry, Chemical Physics - PCCP. ISSN 1463-9076. 21(25), p. 13539–13544. doi: 10.1039/c9cp01337g. Full text in Research Archive
• Ponthus, Nicolas; Scheibert, Julien; Thøgersen, Kjetil; Malthe-Sørenssen, Anders & Perret-Liaudet, Joel (2019). Statistics of the separation between sliding rigid rough surfaces: Simulations and extreme value theory approach. Physical Review E (PRE). ISSN 2470-0045. 99(2). doi: 10.1103/PhysRevE.99.023004. Full text in Research Archive
• Solbrå, Andreas Våvang; Bergersen, Aslak Wigdahl; van den Brink, Jonas; Malthe-Sørenssen, Anders; Einevoll, Gaute & Halnes, Geir (2018). A Kirchhoff-Nernst-Planck framework for modeling large scale extracellular electrodiffusion surrounding morphologically detailed neurons. PLoS Computational Biology. ISSN 1553-734X. 14(10), p. 1–26. doi: 10.1371/journal.pcbi.1006510. Full text in Research Archive
• Gløersen, Øyvind Nøstdahl; Losnegard, Thomas Johansen; Malthe-Sørenssen, Anders; Dysthe, Dag Kristian & Gilgien, Matthias (2018). Propulsive Power in Cross-Country Skiing: Application and Limitations of a Novel Wearable Sensor-Based Method During Roller Skiing. Frontiers in Physiology. ISSN 1664-042X. 9, p. 1–14. doi: 10.3389/fphys.2018.01631. Full text in Research Archive Show summary

  Cross-country skiing is an endurance sport that requires extremely high maximal aerobic power. Due to downhill sections where the athletes can recover, skiersmust also have the ability to perform repeated efforts where metabolic power substantially exceeds maximal aerobic power. Since the duration of these supra-aerobic efforts is often in the order of seconds, heart rate, and pulmonary VO2 do not adequately reflect instantaneous metabolic power. Propulsive power (Pprop) is an alternative parameter that can be used to estimate metabolic power, but the validity of such calculations during cross-country skiing has rarely been addressed. The aim of this study was therefore twofold: to develop a procedure using small non-intrusive sensors attached to the athlete for estimating Pprop during roller-skiing and to evaluate its limits; and (2) to utilize this procedure to determine the Pprop generated by high-level skiers during a simulated distance race. Eight elite male cross-country skiers simulated a 15 km individual distance race on roller skis using ski skating techniques on a course (13.5 km) similar to World Cup skiing courses. Pprop was calculated using a combination of standalone and differential GNSS measurements and inertial measurement units. The method’s measurement error was assessed using a Monte Carlo simulation, sampling from the most relevant sources of error. Pprop decreased approximately linearly with skiing speed and acceleration, and was approximated by the equation Pprop(v, ˙v) = −0.54·v −0.71·˙v + 7.26 W·kg−1. Pprop was typically zero for skiing speeds >9 m·s−1, because the athletes transitioned to the tuck position. Peak Pprop was 8.35 ± 0.63 W·kg−1 and was typically attained during the final lap in the last major ascent, while average Pprop throughout the race was 3.35 ± 0.23 W·kg−1. The measurement error of Pprop increased with skiing speed, from 0.09 W·kg−1 at 2.0 m·s−1 to 0.58 W·kg−1 at 9.0 m·s−1. In summary, this study is the first to provide continuous measurements of Pprop for distance skiing, as well as the first to quantify the measurement error during roller skiing using the power balance principle. Therefore, these results provide novel insight into the pacing strategies employed by high-level skiers.

• Aupart, Claire Olga Maryse; Dunkel, Kristina G; Angheluta, Luiza; Austrheim, Håkon Olaf; Ildefonse, Beniot & Malthe-Sørenssen, Anders [Show all 7 contributors for this article] (2018). Olivine Grain Size Distributions in Faults and Shear Zones: Evidence for Nonsteady State Deformation. Journal of Geophysical Research (JGR): Solid Earth. ISSN 2169-9313. 123(9), p. 7421–7443. doi: 10.1029/2018JB015836. Full text in Research Archive
• Dragly, Svenn-Arne; Mobarhan, Milad; Lepperød, Mikkel Elle; Tennøe, Simen; Fyhn, Marianne & Hafting, Torkel [Show all 7 contributors for this article] (2018). Experimental directory structure (Exdir): An alternative to HDF5 without introducing a new file format. Frontiers in Neuroinformatics. ISSN 1662-5196. 12. doi: 10.3389/fninf.2018.00016.
• Thompson, Elise Holter; Lensjø, Kristian Kinden; Wigestrand, Mattis B; Malthe-sørenssen, Anders; Hafting, Torkel & Fyhn, Marianne (2018). Removal of perineuronal nets disrupts recall of a remote fear memory. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 115(3), p. 607–612. doi: 10.1073/pnas.1713530115. Full text in Research Archive
• Plümper, Oliver; Botan, Alexandru; Los, Catharina; Liu, Yang; Malthe-Sørenssen, Anders & Jamtveit, Bjørn (2017). Fluid-driven metamorphism of the continental crust governed by nanoscale fluid flow. Nature Geoscience. ISSN 1752-0894. 10(9), p. 685–690. doi: 10.1038/ngeo3009. Full text in Research Archive
• Dragly, Svenn-Arne; Mobarhan, Milad; Solbrå, Andreas Våvang; Tennøe, Simen; Hafreager, Anders & Malthe-Sørenssen, Anders [Show all 9 contributors for this article] (2017). Neuronify: An educational simulator for neural circuits. eNeuro. ISSN 2373-2822. 4(2:e0022-17.2017), p. 1–13. doi: 10.1523/ENEURO.0022-17.2017. Full text in Research Archive
• Huang, Hai; Meakin, Paul & Malthe-Sørenssen, Anders (2016). Physics-based simulation of multiple interacting crack growth in brittle rocks driven by thermal cooling. International journal for numerical and analytical methods in geomechanics (Print). ISSN 0363-9061. 40(16), p. 2163–2177. doi: 10.1002/nag.2523.
• Thøgersen, Kjetil; Dabrowski, Marcin & Malthe-Sørenssen, Anders (2016). Transient cluster formation in sheared non-Brownian suspensions. Physical Review E (PRE). ISSN 2470-0045. 93(2). doi: 10.1103/PhysRevE.93.022611.
• Malthe-Sørenssen, Anders; Hjorth-Jensen, Morten; Langtangen, Hans Petter & Mørken, Knut Martin (2015). Integrasjon av beregninger i fysikkundervisningen. UNIPED. ISSN 1500-4538. 38(4), p. 303–310.
• Amundsen, David Skålid; Trømborg, Jørgen Kjoshagen; Thøgersen, Kjetil; Katzav, Eytan; Malthe-Sørenssen, Anders & Scheibert, Julien (2015). Steady-state propagation speed of rupture fronts along one-dimensional frictional interfaces. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. ISSN 1539-3755. 92(3). doi: 10.1103/PhysRevE.92.032406.
• Trømborg, Jørgen Kjoshagen; Sveinsson, Henrik Andersen; Thøgersen, Kjetil; Scheibert, Julien & Malthe-Sørenssen, Anders (2015). Speed of fast and slow rupture fronts along frictional interfaces. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. ISSN 1539-3755. 92(1). doi: 10.1103/PhysRevE.92.012408.
• Shekhar, Adarsh; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya; Alm, Camilla Kirkemo & Malthe-Sørenssen, Anders (2014). Universal stretched exponential relaxation in nanoconfined water. Applied Physics Letters. ISSN 0003-6951. 105(16). doi: 10.1063/1.4899279.
• Ulven, Ole Ivar; Jamtveit, Bjørn & Malthe-Sørenssen, Anders (2014). Reaction-driven fracturing of porous rock. Journal of Geophysical Research (JGR): Solid Earth. ISSN 2169-9313. 119(10), p. 7473–7486. doi: 10.1002/2014JB011102.
• Hafver, Andreas; Jettestuen, Espen; Feder, Jens ; Meakin, Paul & Malthe-Sørenssen, Anders (2014). A node-splitting discrete element model for fluid-structure interaction. Physica A: Statistical Mechanics and its Applications. ISSN 0378-4371. 416, p. 61–79. doi: 10.1016/j.physa.2014.08.039.
• Ulven, Ole Ivar; Storheim, Håkon; Austrheim, Håkon Olav & Malthe-Sørenssen, Anders (2014). Fracture initiation during volume increasing reactions in rocks and applications for CO2 sequestration. Earth and Planetary Science Letters. ISSN 0012-821X. 389, p. 132–142. doi: 10.1016/j.epsl.2013.12.039.
• Hafver, Andreas; Jettestuen, Espen; Kobchenko, Maya; Dysthe, Dag Kristian; Meakin, Paul & Malthe-Sørenssen, Anders (2014). Classification of fracture patterns by heterogeneity and topology. Europhysics letters. ISSN 0295-5075. 105(5). doi: 10.1209/0295-5075/105/56004.
• Thiyam, Priyadarshini; Persson, Clas; Sernelius, Bo. E.; Parsons, Drew F.; Malthe-Sørenssen, Anders & Boström, Mathias (2014). Intermolecular Casimir-Polder forces in water and near surfaces. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. ISSN 1539-3755. 90(3). doi: 10.1103/PhysRevE.90.032122.
• Hafver, Andreas; Jettestuen, Espen; Baetens, Jan M. & Malthe-Sørenssen, Anders (2014). Network formation by contact arrested propagation. Physica A: Statistical Mechanics and its Applications. ISSN 0378-4371. 413, p. 240–255. doi: 10.1016/j.physa.2014.07.006.
• Trømborg, Jørgen Kjoshagen; Sveinsson, Henrik Andersen; Scheibert, Julien; Thøgersen, Kjetil; Amundsen, David Skålid & Malthe-Sørenssen, Anders (2014). Slow slip and the transition from fast to slow fronts in the rupture of frictional interfaces. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 111(24), p. 8764–8769. doi: 10.1073/pnas.1321752111.
• Thøgersen, Kjetil; Trømborg, Jørgen Kjoshagen; Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders & Scheibert, Julien (2014). History-dependent friction and slow slip from time-dependent microscopic junction laws studied in a statistical framework. Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. ISSN 1539-3755. 89(5). doi: 10.1103/PhysRevE.89.052401. Full text in Research Archive
• Meakin, Paul; Huang, Hai; Malthe-Sørenssen, Anders & Thøgersen, Kjetil (2013). Shale gas: Opportunities and challenges. Environmental Geosciences. ISSN 1075-9565. 20(4), p. 151–164. doi: 10.1306/eg.05311313005.
• Panahi, Hamed; Meakin, Paul; Renard, Francois Marie Paul L; Kobchenko, Maya; Scheibert, Julien & Mazzini, Adriano [Show all 9 contributors for this article] (2013). A 4D Synchrotron X-Ray-Tomography Study of the Formation of Hydrocarbon-Migration Pathways in Heated Organic-Rich Shale. SPE Journal. ISSN 1086-055X. 18(2), p. 366–377. doi: 10.2118/162939-PA.
• Malvoisin, Benjamin; Austrheim, Håkon Olav; Malthe-Sørenssen, Anders & Glodny, Johannes (2012). Deformation-related alteration of basaltic clasts during deep burial in sedimentary basins. Chemical Geology. ISSN 0009-2541. 322-323, p. 47–67. doi: 10.1016/j.chemgeo.2012.06.011.
• Amundsen, David Skålid; Scheibert, Julien; Thøgersen, Kjetil; Trømborg, Jørgen & Malthe-Sørenssen, Anders (2012). 1D Model of Precursors to Frictional Stick-Slip Motion Allowing for Robust Comparison with Experiments. Tribology letter. ISSN 1023-8883. 45(2), p. 357–369. doi: 10.1007/s11249-011-9894-3.
• Jamtveit, Bjørn; Kobchenko, Maya; Austrheim, Håkon Olav; Malthe-Sørenssen, Anders; Røyne, Anja & Svensen, Henrik (2011). Porosity evolution and crystallization-driven fragmentation during weathering of andesite. Journal of Geophysical Research (JGR): Solid Earth. ISSN 2169-9313. 116. doi: 10.1029/2011JB008649.
• Kobchenko, Maya; Panahi, Hamed; Renard, Francois Marie Paul L; Dysthe, Dag Kristian; Malthe-Sørenssen, Anders & Mazzini, Adriano [Show all 9 contributors for this article] (2011). 4D imaging of fracturing in organic-rich shales during heating. Journal of Geophysical Research (JGR): Solid Earth. ISSN 2169-9313. 116(12). doi: 10.1029/2011JB008565.

View all works in Cristin

• Malthe-Sørenssen, Anders (2015). Elementary Mechanics Using Python. Springer. ISBN 978-3-319-19595-7. 590 p.
• Malthe-Sørenssen, Anders (2015). Elementary Mechanics Using Matlab. Springer. ISBN 978-3-319-19586-5. 590 p.

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• Camposano, Anthony Val Canillas; Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2024). Machine Learning an All-Atom Empirical Force Field for a Water-Silica System. Show summary

  Molecular modeling of the interaction between silica and water provides a better understanding of how water affects rocks and glasses at the nanoscale. Here, we parametrize a new classical dissociative force field for the water–silica system. We create a classical force field capable of reactive interactions between all chemical species in the water–silica system, using the same functional form by Vashishta et al. to describe bulk water, silica, and silica–water interactions. Using a hierarchical genetic algorithm as a global optimizer and the Nelder-Mead simplex algorithm as a local optimizer, we parameterized the Vashishta force field to reproduce the density, transport properties, and vapor-liquid properties of water. We then used the same method to obtain water–silica interaction parameters to reproduce gas phase orthosilicic geometry and silica surface properties such as silanol concentration, heat of immersion, and the wettability angle of water on a silica surface. For oxygen–silicon interactions in silica, we reuse an existing Vashishta potential parameter set that has been parameterized to reproduce bulk mechanical behavior, surface properties, and fracture properties. Our developed force field can be used to study processes such as dissolution, friction, and stress corrosion fracture in the presence of water over a wide range of thermodynamic conditions for larger-scale and longer-scale simulations.

• Camposano, Anthony Val Canillas; Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2023). Tuning Vashishta Potential for Water.
• Bakke, Jostein; Langford, Malcolm; Børrud, Elin; Cotner, Sehoya Harris; Engebretsen, Eivind & Graver, Fredrik (Georg Fredrik) [Show all 14 contributors for this article] (2023). Fremtidens høyere utdanning trenger en oppgradering - ikke budsjettkutt! Khrono.no. ISSN 1894-8995.
• Sveinsson, Henrik Andersen; Thøgersen, Kjetil & Malthe-Sørenssen, Anders (2023). Grain boundary behavior of hydrate–hydrate and ice—ice bicrystals: molecular dynamics insights.
• Schøyen, Vemund Sigmundson; Pettersen, Markus Borud; Holzhousen, Konstantin; Fyhn, Marianne; Malthe-Sørenssen, Anders & Elle Lepperød, Mikkel (2022). Coherently Remapping Toroidal Cells But Not Grid Cells are Responsible for Path Integration in Virtual Agents. bioRxiv. ISSN 2692-8205. doi: 10.1101/2022.08.18.504379.
• Idsøe, Ella Maria Cosmovici & Malthe-Sørenssen, Anders (2021). Experiences from Establishing a Cross-Disciplinary Honors Program at the University of Oslo.
• Maasø, Arnt; Brevik, Lisbeth M.; Vasbø, Kristin Beate; Breivik, Jarle; Lerheim, Birgitte & Malthe-Sørenssen, Anders [Show all 7 contributors for this article] (2021). Dette må bli læringsmiljøets år. Khrono.no. ISSN 1894-8995.
• Sveinsson, Henrik Andersen; Thøgersen, Kjetil & Malthe-Sørenssen, Anders (2020). Grain boundary behavior of hydrate–hydrate and ice–ice bicrystals: Molecular dynamics insights.
• Guren, Marthe Grønlie; Zheng, Xiaojiao; Jamtveit, Bjørn; Hafreager, Anders; Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders [Show all 7 contributors for this article] (2019). Molecular dynamics simulations of the hydration force and transport properties of a water film during reaction-induced fracturing.
• Fyhn, Marianne; Malthe-Sørenssen, Anders; Mørken, Knut Martin; Nederbragt, Alexander Johan; Odden, Tor Ole & Sundnes, Joakim (2019). Beregningsorientering og utdanningsutvikling.
• Odden, Tor Ole & Malthe-Sørenssen, Anders (2019). Computational Essays and Computational Literacy at the University of Oslo.
• Razbani, Mohammad Amin; Zehner, Jennifer Simone; Jettestuen, Espen; Røyne, Anja; Sikorski, Pawel & Malthe-Sørenssen, Anders (2019). A pore-scale model of microbially induced calcium carbonate precipitation.
• Thøgersen, Kjetil; Schuler, Thomas & Malthe-Sørenssen, Anders (2019). Nå er isbreene fravristet noen av sine dypeste hemmeligheter. [Business/trade/industry journal]. titan.uio.no og Teknisk Ukeblad.
• Plümper, Oliver; Botan, Alexandru; Los, Catharina; Liu, Yang; Malthe-Sørenssen, Anders & Jamtveit, Bjørn (2019). Erratum to: Fluid-driven metamorphism of the continental crust governed by nanoscale fluid flow (Nature Geoscience, (2017), 10, 9, (685-690), 10.1038/ngeo3009). Nature Geoscience. ISSN 1752-0894. 12(1). doi: 10.1038/s41561-018-0276-4.
• Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders & Ning, Fulong (2018). Mechanisms of shear fracture in polycrystalline methane hydrates.
• Solbrå, Andreas Våvang; Bergersen, Aslak Wigdahl; van den Brink, Jonas; Malthe-Sørenssen, Anders; Einevoll, Gaute & Halnes, Geir (2018). Modeling electrodiffusion in the extracellular space around a morphologically detailed neuron.
• Dragly, Svenn-Arne; Mobarhan, Milad; Lepperød, Mikkel Elle; Tennøe, Simen; Stasik, Alexander Johannes & Fyhn, Marianne [Show all 8 contributors for this article] (2018). Exdir An alternative to HDF5 that uses Numpy files for data, YAML for metadata and simple directories to define the hierarchy.
• Thøgersen, Kjetil; Malthe-Sørenssen, Anders; Sveinsson, Henrik Andersen & Scheibert, Julien (2018). Modeling the onset of frictional sliding.
• Sveinsson, Henrik Andersen; Hafreager, Anders; Vashishta, Priya; Malthe-Sørenssen, Anders & Kalia, Rajiv K. (2018). Molecular dynamics simulations of faceting of silicon carbide nanoparticles.
• Hafreager, Anders; Dragly, Svenn-Arne & Malthe-Sørenssen, Anders (2018). Increased productivity with real time atomistic simulations using Atomify.
• Karlsen, Emil; Zehner, Jennifer Simone; Razbani, Mohammad Amin; Jettestuen, Espen; Malthe-sørenssen, Anders & Wentzel, Alexander [Show all 9 contributors for this article] (2018). Metabolic modelling, reactive transport modelling, and experimental verification of microbial-induced processes in the production of bio-concrete.
• Aupart, Claire Olga Maryse; Dunkel, Kristina Grete; Angheluta-Bauer, Luiza; Austrheim, Håkon; Ildefonse, Benoit & Malthe-Sørenssen, Anders [Show all 7 contributors for this article] (2017). Grain size distribution evolution in shear zones: a study case in the Leka Ophiolite Complex (LOC).
• Malthe-sørenssen, Anders; Henriksen, Ellen Karoline; Hjorth-Jensen, Morten; Mørken, Knut Martin; Sølna, Hanne & Tellefsen, Cathrine Wahlstrøm (2017). Center for computing in science education: fornyelse av utdanning ved integrasjon av beregninger. Nordic Journal of STEM Education. ISSN 2535-4574. 1(1), p. 236–241.
• Malthe-sørenssen, Anders (2017). En forskningsnær utdanning ved integrasjon av databeregninger og programmering.
• Malthe-sørenssen, Anders (2017). Dyp digital kompetanse - hvordan sikrer vi at studentene blir kompetente i et internasjonal, digital arbeidsmarked.
• Malthe-sørenssen, Anders; Sveinsson, Henrik Andersen; Trømborg, Jørgen Kjoshagen; Thøgersen, Kjetil & scheiber, julien (2017). Frictional behavior across scale.
• Malthe-sørenssen, Anders (2017). Center for Computing in Science Education.
• Malthe-sørenssen, Anders (2017). Integrating computing in undergraduate physics education.
• Malthe-sørenssen, Anders (2017). Integration of computing in physics education.
• Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2017). Thermally Activated Slow Crack Evolution in Single Crystal Methane Hydrates.
• Mørken, Knut Martin; Hjorth-Jensen, Morten; Langtangen, Hans Petter & Malthe-Sørenssen, Anders (2016). How should computers influence the mathematics curriculum?
• Mørken, Knut Martin; Hjorth-Jensen, Morten; Langtangen, Hans Petter & Malthe-Sørenssen, Anders (2016). Computing across the curriculum.
• Solbrå, Andreas Våvang; Einevoll, Gaute; Malthe-Sørenssen, Anders & Halnes, Geir (2016). A novel electrodiffusive scheme for modeling ion dynamics in neural tissue.
• Solbrå, Andreas Våvang; Malthe-Sørenssen, Anders; Einevoll, Gaute & Halnes, Geir (2016). A novel electrodiffusive scheme for modeling ion dynamics in neural tissue.
• Ulven, Ole Ivar & Malthe-Sørenssen, Anders (2016). Reaction induced fracturing: chemical-mechanical feedback.
• Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2016). Molecular dynamics modeling of tensile cracks in methane hydrates. Show summary

  Production of methane from hydrates is significantly different from producing from a porous matrix, as the material itself disappears during production. Stress heterogeneities arising when methane hydrates dissociate may trigger fractures in the material, and drive further dissociation through fracture of the hydrate. The unstable nature of the gas hydrates renders it di cult to study its mechanical and failure properties experimentally. Even simple characteristics such as the mode I fracture toughness are hard to obtain. In this study, we use molecular dynamics simulations to obtain fracture properties of methane hydrates, with a main focus on crack initiation. We find that on the nanosecond scale, an important crack initiation mechanism is the slow growth of initial cracks due to melting. Rapid cracks start propagating when the system configuration reach a state close to the Griffith fracture criterion from continuum fracture mechanics. The nature of the process taking the system from an uncritical to a critical state is well described by a relation based on Arrhenius’ equation.

• Ulven, Ole Ivar; Sun, WaiChing & Malthe-Sørenssen, Anders (2015). Fluid transport in reaction induced fractures.
• Ulven, Ole Ivar; Beinlich, Andreas; Sun, WaiChing; Malthe-Sørenssen, Anders & Austrheim, Håkon Olav (2015). Fracture Formation due to Growth of Hydrous Carbonates.
• Mørken, Knut Martin; Hjorth-Jensen, Morten; Langtangen, Hans Petter & Malthe-Sørenssen, Anders (2015). Tanker om digital realfagsundervisning.
• Mørken, Knut Martin; Hjorth-Jensen, Morten; Langtangen, Hans Petter & Malthe-Sørenssen, Anders (2015). Some reflections on the impact of computers in science education.
• Thøgersen, Kjetil; Hafreager, Anders; Hafver, Andreas & Malthe-Sørenssen, Anders (2014). Numerical modeling of processes in extraction of gas from tight reservoirs.
• Ulven, Ole Ivar; Austrheim, Håkon Olav; Hövelmann, Jörn-Erik; Beinlich, Andreas & Malthe-Sørenssen, Anders (2014). Fragmentation and Carbonation of Serpentinized Dunites.
• Sveinsson, Henrik Andersen; Trømborg, Jørgen Kjoshagen & Malthe-Sørenssen, Anders (2014). Sommervikar ble toppforsker. [Newspaper]. Dagens Nærlingsliv.
• Høgberget, Jørgen; Røyne, Anja; Malthe-Sørenssen, Anders; Dysthe, Dag Kristian & Jettestuen, Espen (2014). Nanoconfined Crystal Growth and Dissolution.
• Trømborg, Jørgen; Amundsen, David Skålid; Thøgersen, Kjetil; Sveinsson, Henrik Andersen; Scheibert, Julien & Malthe-Sørenssen, Anders (2012). Modelling the Onset of Frictional Sliding.
• Thøgersen, Kjetil; Trømborg, Jørgen; Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders; Scheibert, Julien & Amundsen, David Skålid (2012). Complex frictional behaviour explained by connecting models at different length scales.
• Trømborg, Jørgen; Amundsen, David Skålid; Thøgersen, Kjetil; Scheibert, Julien & Malthe-Sørenssen, Anders (2012). Precursor evolution in recent dry friction experiments explained by 2D simulation.
• Trømborg, Jørgen; Amundsen, David Skålid; Thøgersen, Kjetil; Scheibert, Julien & Malthe-Sørenssen, Anders (2012). 1+1D modelling of sliding initiation: Application to recent dry friction experiments.
• Sveinsson, Henrik Andersen & Malthe-Sørenssen, Anders (2015). Molecular Modeling of Fracture in Methane Hydrates. Universitetet i Oslo.

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