Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Letter
  • Open Access

Transport-generated signals uncover geometric features of evolving branched structures

Fabian H. Kreten, Ludger Santen, and Reza Shaebani*

  • Department of Theoretical Physics and Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany

  • *Contact author: shaebani@lusi.uni-sb.de

Phys. Rev. Research 8, L012051 – Published 3 March, 2026

DOI: https://doi.org/10.1103/bnnl-xnm6

Abstract

Branched structures that evolve over time critically shape the function of diverse natural and engineered systems, from neuronal dendrites and vascular networks to pulmonary and root architectures. Inferring their hidden geometric properties and monitoring their morphological evolution remain major challenges, as direct imaging or tracer tracking is often infeasible, especially in living systems. Here, we introduce a general theoretical framework to recover the structural features of evolving branched geometries by analyzing the collective signals generated by tracer particles during transport. As tracers traverse the structure, they emit detectable pulses upon reaching an observation site. We show that the statistical properties of the resulting signal intensity, which reflects underlying first-passage dynamics, encode key morphological descriptors such as network extent, directional bias, and local trapping frequency. The strength of our approach lies in enabling quantitative inference of geometric parameters from time-series data recorded at a single observation site. This theoretical framework is designed to guide and motivate future experimental studies in systems where direct imaging is not feasible. Unlike conventional tracer-tracking methods, our approach enables noninvasive inference of hidden geometry solely from externally measurable signals, requiring no access to individual trajectories or internal measurements. This conceptual advance opens an avenue for transport-based structural inference and provides a scalable strategy for probing dynamic, complex architectures across biological, physical, and synthetic systems.

View figure in article

Physics Subject Headings (PhySH)

Article Text

Supplemental Material

References (75)

  1. P. Ball, Branches: Nature's Patterns: A Tapestry in Three Parts (Oxford University Press, Oxford, UK, 2009).
  2. L. Koçillari, et al., The widened pipe model of plant hydraulic evolution, Proc. Natl. Acad. Sci. USA 118, e2100314118 (2021).
  3. S. Randriamanantsoa, A. Papargyriou, H. C. Maurer, K. Peschke, M. Schuster, G. Zecchin, K. Steiger, R. Öllinger, D. Saur, C. Scheel, R. Rad, E. Hannezo, M. Reichert, and A. R. Bausch, Spatiotemporal dynamics of self-organized branching in pancreas-derived organoids, Nat. Commun. 13, 5219 (2022).
  4. M. Liao, X. Liang, and J. Howard, The narrowing of dendrite branches across nodes follows a well-defined scaling law, Proc. Natl. Acad. Sci. USA 118, e2022395118 (2021).
  5. R. Jose, L. Santen, and M. R. Shaebani, Trapping in and escape from branched structures of neuronal dendrites, Biophys. J. 115, 2014 (2018).
  6. J. T. Perron, P. W. Richardson, K. L. Ferrier, and M. Lapôtre, The root of branching river networks, Nature (London) 492, 100 (2012).
  7. P. Desai-Chowdhry, A. B. Brummer, and V. M. Savage, How axon and dendrite branching are guided by time, energy, and spatial constraints, Sci. Rep. 12, 20810 (2022).
  8. S. V. Grigoriev, O. D. Shnyrkov, P. M. Pustovoit, E. G. Iashina, and K. A. Pshenichnyi, Experimental evidence for logarithmic fractal structure of botanical trees, Phys. Rev. E 105, 044412 (2022).
  9. A. Rinaldo, R. Rigon, J. R. Banavar, A. Maritan, and I. Rodriguez-Iturbe, Evolution and selection of river networks: Statics, dynamics, and complexity, Proc. Natl. Acad. Sci. USA 111, 2417 (2014).
  10. D. Borse and B. Biswal, A novel probabilistic model to explain drainage network evolution, Adv. Water Resour. 171, 104342 (2023).
  11. B. Wu, Y. Lin, Z. Zhang, and G. Chen, Trapping in dendrimers and regular hyperbranched polymers, J. Chem. Phys. 137, 044903 (2012).
  12. B. Zhou, Q. Cheng, Z. Chen, Z. Chen, D. Liang, E. A. Munro, G. Yun, Y. Kawai, J. Chen, T. Bhowmick, K. K. Padmanathan, L. G. Occhipinti, H. Matsumoto, J. W. Gardner, B.-L. Su, and T. Hasan, Universal Murray's law for optimised fluid transport in synthetic structures, Nat. Commun. 15, 3652 (2024).
  13. X. Zheng, G. Shen, C. Wang, Y. Li, D. Dunphy, T. Hasan, C. J. Brinker, and B.-L. Su, Bio-inspired Murray materials for mass transfer and activity, Nat. Commun. 8, 14921 (2017).
  14. J. R. Banavar, A. Maritan, and A. Rinaldo, Size and form in efficient transportation networks, Nature (London) 399, 130 (1999).
  15. B. Schäfer, T. Pesch, D. Manik, J. Gollenstede, G. Lin, H.-P. Beck, D. Witthaut, and M. Timme, Understanding Braess’ paradox in power grids, Nat. Commun. 13, 5396 (2022).
  16. L. Yang, H. Xiao, Y. Qian, X. Zhao, X.-Y. Kong, P. Liu, W. Xin, L. Fu, L. Jiang, and L. Wen, Bioinspired hierarchical porous membrane for efficient uranium extraction from seawater, Nat. Sustain. 5, 71 (2022).
  17. R. Pastor-Satorras, C. Castellano, P. V. Mieghem, and A. Vespignani, Epidemic processes in complex networks, Rev. Mod. Phys. 87, 925 (2015).
  18. M. E. J. Newman, Networks: An Introduction (Oxford University Press, New York, 2010).
  19. J. M. Kleinberg, Navigation in a small world, Nature (London) 406, 845 (2000).
  20. B. Bollobás and O. Riordan, Shortest paths and load scaling in scale-free trees, Phys. Rev. E 69, 036114 (2004).
  21. N. Spruston, Pyramidal neurons: dendritic structure and synaptic integration, Nat. Rev. Neurosci. 9, 206 (2008).
  22. M. Felici, M. Filoche, and B. Sapoval, Renormalized random walk study of oxygen absorption in the human lung, Phys. Rev. Lett. 92, 068101 (2004).
  23. M. P. Forrest, E. Parnell, and P. Penzes, Dendritic structural plasticity and neuropsychiatric disease, Nat. Rev. Neurosci. 19, 215 (2018).
  24. D. ben Avraham and S. Havlin, Diffusion and Reactions in Fractals and Disordered Systems (Cambridge University Press, Cambridge, UK, 2000).
  25. R. W. Mair, G. P. Wong, D. Hoffmann, M. D. Hürlimann, S. Patz, L. M. Schwartz, and R. L. Walsworth, Probing porous media with gas diffusion NMR, Phys. Rev. Lett. 83, 3324 (1999).
  26. P. Tierno and M. R. Shaebani, Enhanced diffusion and anomalous transport of magnetic colloids driven above a two-state flashing potential, Soft Matter 12, 3398 (2016).
  27. R. Krishna, Describing the diffusion of guest molecules inside porous structures, J. Phys. Chem. C 113, 19756 (2009).
  28. M. R. Shaebani, R. Jose, C. Sand, and L. Santen, Unraveling the structure of treelike networks from first-passage times of lazy random walkers, Phys. Rev. E 98, 042315 (2018).
  29. F. H. Kreten, L. Santen, and R. Shaebani, Inferring tree structure with hidden traps from first-passage times, Phys. Rev. E 112, 054306 (2025).
  30. Y. Siantos, C. Cooper, and T. Radzik, Fast low-cost estimation of network properties using random walks, Internet Math. 12, 221 (2016).
  31. E. Agliari, R. Burioni, D. Cassi, and F. M. Neri, Autocatalytic reaction on low-dimensional substrates, Theor. Chem. Acc. 118, 855 (2007).
  32. Z. Sadjadi, M. Miri, M. R. Shaebani, and S. Nakhaee, Diffusive transport of light in a two-dimensional disordered packing of disks: Analytical approach to transport mean free path, Phys. Rev. E 78, 031121 (2008).
  33. See Supplemental Material at http://link.aps.org/supplemental/10.1103/bnnl-xnm6 for (1) the analytical proofs of mapping between the model parameters and geometric characteristics of the structure, (2) an error analysis and numerical validation section, (3) three illustrative applications of our proposed approach, and (4) a few figures that illustrate the mapping between these two phase spaces, which also includes Refs.  [60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75].
  34. L. Dagdug, A. M. Berezhkovskii, Y. A. Makhnovskii, and V. Y. Zitserman, Transient diffusion in a tube with dead ends, J. Chem. Phys. 127, 224712 (2007).
  35. C. D. Murray, The physiological principle of minimum work: I. The vascular system and the cost of blood volume., Proc. Natl. Acad. Sci. USA 12, 207 (1926).
  36. W. Rall, Branching dendritic trees and motoneuron membrane resistivity, Exp. Neurol. 1, 491 (1959).
  37. E. Agliari, A. Blumen, and O. Mülken, Dynamics of continuous-time quantum walks in restricted geometries, J. Phys. A 41, 445301 (2008).
  38. R. Metzler, S. Redner, and G. Oshanin, First-Passage Phenomena and Their Applications (World Scientific, Singapore, 2014), pp. 96–121.
  39. S. Redner, A Guide to First-Passage Processes (Cambridge University Press, Cambridge, UK, 2001).
  40. B. D. Hughes and M. Sahimi, Random walks on the Bethe lattice, J. Stat. Phys. 29, 781 (1982).
  41. L. Skarpalezos, A. Kittas, P. Argyrakis, R. Cohen, and S. Havlin, Anomalous biased diffusion in networks, Phys. Rev. E 88, 012817 (2013).
  42. Y.-N. Jan and L. Y. Jan, Branching out: Mechanisms of dendritic arborization, Nat. Rev. Neurosci. 11, 316 (2010).
  43. H. Hering and M. Sheng, Dendritic spines: Structure, dynamics and regulation, Nat. Rev. Neurosci. 2, 880 (2001).
  44. P. Penzes, M. E. Cahill, K. A. Jones, J.-E. VanLeeuwen, and K. M. Woolfrey, Dendritic spine pathology in neuropsychiatric disorders, Nat. Neurosci. 14, 285 (2011).
  45. C. Tackenberg, A. Ghori, and R. Brandt, Thin, stubby or mushroom: Spine pathology in Alzheimer's disease, Curr. Alzheimer Res. 6, 261 (2009).
  46. M. Martone, D. Price, A. Thor, H. Hakozaki, and M. Terada, CIL:40021, Mus musculus, Purkinje cell. Cil. Dataset (RRID:SCR_003510) (2012), https://doi.org/doi:10.7295/W9CIL40021.
  47. R. Benavides-Piccione, I. Fernaud-Espinosa, V. Robles, R. Yuste, and J. DeFelipe, Age-based comparison of human dendritic spine structure using complete three-dimensional reconstructions, Cereb. Cortex 23, 1798 (2013).
  48. M. Rapp, I. Segev, and Y. Yarom, Physiology, morphology and detailed passive models of guinea-pig cerebellar Purkinje cells, J. Physiol. 474, 101 (1994).
  49. K. M. Harris, F. E. Jensen, and B. Tsao, Three-dimensional structure of dendritic spines and synapses in rat hippocampus (CA1) at postnatal day 15 and adult ages: implications for the maturation of synaptic physiology and long-term potentiation, J. Neurosci. 12, 2685 (1992).
  50. J. A. Stanley and N. Raz, Functional magnetic resonance spectroscopy: The new MRS for cognitive neuroscience and psychiatry research, Front. Psychiatry 9, 76 (2018).
  51. S. D. Bass, S. Mariazzi, P. Moskal, and E. Stepien, Colloquium: Positronium physics and biomedical applications, Rev. Mod. Phys. 95, 021002 (2023).
  52. R. S. Koolschijn, W. T. Clarke, I. B. Ip, U. E. Emir, and H. C. Barron, Event-related functional magnetic resonance spectroscopy, NeuroImage 276, 120194 (2023).
  53. Z. Zhang, J. Guan, Z. Jiang, Y. Yang, J. Liu, W. Hua, Y. Mao, C. Li, W. Lu, J. Qian, and C. Zhan, Brain-targeted drug delivery by manipulating protein corona functions, Nat. Commun. 10, 3561 (2019).
  54. C. Saraiva, C. Praca, R. Ferreira, T. Santos, L. Ferreira, and L. Bernardino, Nanoparticle-mediated brain drug delivery: Overcoming blood-brain barrier to treat neurodegenerative diseases, J. Controlled Release 235, 34 (2016).
  55. C. Yan, J. Gu, S. Yin, H. Wu, X. Lei, F. Geng, N. Zhang, and X. Wu, Design and preparation of naringenin loaded functional biomimetic nano-drug delivery system for Alzheimer's disease, J. Drug Target. 32, 80 (2024).
  56. R. Yasuda and H. Murakoshi, The mechanisms underlying the spatial spreading of signaling activity, Curr. Opin. Neurobiol. 21, 313 (2011).
  57. F. Santamaria, S. Wils, E. De Schutter, and G. J. Augustine, Anomalous diffusion in Purkinje cell dendrites caused by spines, Neuron 52, 635 (2006).
  58. F. H. Kreten, B. A. Niemeyer, L. Santen, and R. Shaebani, Tracking the morphological evolution of neuronal dendrites by first-passage analysis, Biophys. J. 125, 64 (2026).
  59. F. H. Kreten, L. Santen, and R. Shaebani, Dataset for “Transport-generated signals uncover geometric features of evolving branched structures”, Zenodo (2026), doi: 10.5281/zenodo.18330000.
  60. R. Zwanzig, Diffusion past an entropy barrier, J. Phys. Chem. 96, 3926 (1992).
  61. C. W. Gardiner, Handbook of Stochastic Methods for Physics, Chemistry and the Natural Sciences, Springer Series in Synergetics, 2nd ed. (Springer, Berlin, 1997), Vol. 13.
  62. N. Van Kampen, Stochastic Processes in Physics and Chemistry (Elsevier Science, The Netherlands, 2011).
  63. E. R. Weibel, Morphometry of the Human Lung (Springer, Berlin, 1963).
  64. T. F. Sherman, On connecting large vessels to small. The meaning of Murray's law, J. Gen. Physiol. 78, 431 (1981).
  65. J. M. Newby and P. C. Bressloff, Quasi-steady state reduction of molecular motor-based models of directed intermittent search, Bull. Math. Biol. 72, 1840 (2010).
  66. A. M. Berezhkovskii and L. Dagdug, Analytical treatment of biased diffusion in tubes with periodic dead ends, J. Chem. Phys. 134, 124109 (2011).
  67. S. Verbanck and M. Paiva, Gas mixing in the airways and airspaces, Compr. Physiol. 1, 809 (2011).
  68. B. Haefeli-Bleuer and E. R. Weibel, Morphometry of the human pulmonary acinus, Anat. Rec. 220, 401 (1988).
  69. P.-R. Burgel, The role of small airways in obstructive airway diseases, Eur. Respir. Rev. 20, 023 (2011).
  70. M. van den Berge, N. H. ten Hacken, J. Cohen, W. R. Douma, and D. S. Postma, Small airway disease in asthma and COPD: Clinical implications, Chest 139, 412 (2011).
  71. A. B. Crawford, M. Makowska, M. Paiva, and L. A. Engel, Convection- and diffusion-dependent ventilation maldistribution in normal subjects, J. Appl. Physiol. 59, 838 (1985).
  72. S. Verbanck, D. Schuermans, A. Van Muylem, M. Paiva, M. Noppen, and W. Vincken, Ventilation distribution during histamine provocation, J. Appl. Physiol. 83, 1907 (1997).
  73. W. M. Gold and L. L. Koth, Chapter 25: Pulmonary function testing, in Murray and Nadel's Textbook of Respiratory Medicine, edited by V. C. Broaddus, R. J. Mason, J. D. Ernst, T. E. King, S. C. Lazarus, J. F. Murray, J. A. Nadel, A. S. Slutsky, and M. B. Gotway, 6th ed. (W.B. Saunders, Philadelphia, PA, 2016), p. 407.
  74. P. D. Robinson, et al., Consensus statement for inert gas washout measurement using multiple- and single-breath tests, Eur. Respir. J. 41, 507 (2013).
  75. E. R. Weibel, B. Sapoval, and M. Filoche, Design of peripheral airways for efficient gas exchange, Respir. Physiol. Neurobiol. 148, 3 (2005).

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation