In this project, supported by the EPSRC, we developed novel theoretical and experimental models to characterise the flow of soft suspensions, such as red blood cells, in porous environments.

• Robust fabrication of ultra-soft tunable PDMS microcapsules as a biomimetic model for red blood cells by Qi Chen, Naval Singh, Kerstin Schirrmann, Qi Zhou, Igor L. Chernyavsky, Anne Juel (2023); Soft Matter 19(28), pp. 5249–5261. doi url

• Red blood cell dynamics in extravascular biological tissues modelled as canonical disordered porous media by Qi Zhou, Kerstin Schirrmann, Eleanor Doman, Qi Chen, Naval Singh, P. Ravi Selvaganapathy, Miguel O. Bernabeu, Oliver E. Jensen, Anne Juel, Igor L. Chernyavsky, Timm Krüger (2022); In Interface Focus. Interface Focus 12(6), pp. 20220037. Royal Society. doi url preprint

• Micro-haemodynamics at the maternal – fetal interface: Experimental, theoretical and clinical perspectives by Qi Zhou, Eleanor Doman, Kerstin Schirrmann, Qi Chen, Elizabeth A. Seed, Edward D. Johnstone, P. Ravi Selvaganapathy, Anne Juel, Oliver E. Jensen, Miguel O. Bernabeu, Timm Krüger, Igor L. Chernyavsky (2022); Current Opinion in Biomedical Engineering 22, pp. 100387. doi url preprint

In this recent project, supported by the ESA and UKSA, we aim to characterise and optimise the rheology of extrusion bioprinting.

• Breakup of extruded filaments of yield-stress fluid by Shamik Hazra, Igor Chernyavsky, Anne Juel (2024); In Bulletin of the American Physical Society. APS. Salt Lake City, USA. url

The human placenta is one of the most fascinating and unusual circulatory systems in the human body. Despite its relatively short span, the placenta is a crucial life-support system that nourishes the developing fetus. In a series of projects supported by the MRC, EPSRC and EU MSCA, we aim to systematically “reverse-engineer” how the placental function is determined by its structure.

• The complexities of the human placenta by Alys R. Clark, Igor L. Chernyavsky, Oliver E. Jensen (2023); Physics Today 76(4), pp. 26–32. doi url preprint

• A massively multi-scale approach to characterizing tissue architecture by synchrotron micro-CT applied to the human placenta by W. M. Tun, G. Poologasundarampillai, H. Bischof, G. Nye, O. N. F. King, M. Basham, Y. Tokudome, R. M. Lewis, E. D. Johnstone, P. Brownbill, M. Darrow, I. L. Chernyavsky (2021); Journal of The Royal Society Interface 18(179), pp. 20210140. doi url preprint

• Quantifying the impact of tissue metabolism on solute transport in feto-placental microvascular networks by Alexander Erlich, Gareth A. Nye, Paul Brownbill, Oliver E. Jensen, Igor L. Chernyavsky (2019); Interface Focus 9(5), pp. 20190021. doi url preprint

• Blood flow and transport in the human placenta by Oliver E. Jensen, Igor L. Chernyavsky (2019); Annual Review of Fluid Mechanics 51, pp. 25–47. doi url preprint

• Physical and geometric determinants of transport in fetoplacental microvascular networks by Alexander Erlich, Philip Pearce, Romina Plitman Mayo, Oliver E. Jensen, Igor L. Chernyavsky (2019); Science Advances 5(4), pp. eaav6326. doi url preprint

• Human placental oxygenation in late gestation: experimental and theoretical approaches by Gareth A. Nye, Emma Ingram, Edward D. Johnstone, Oliver E. Jensen, Henning Schneider, Rohan M. Lewis, Igor L. Chernyavsky, Paul Brownbill (2018); Journal of Physiology 596(23), pp. 5523–5534. doi url preprint

• Image-based modeling of blood flow and oxygen transfer in feto-placental capillaries by Philip Pearce, Paul Brownbill, Jiří Janáček, Marie Jirkovská, Lucie Kubínová, Igor L. Chernyavsky, Oliver E. Jensen (2016); PLoS ONE 11(10), pp. e0165369. doi url preprint

• An international network (PlaNet) to evaluate a human placental testing platform for chemicals safety testing in pregnancy by Paul Brownbill, Igor Chernyavsky, Barbara Bottalico, Gernot Desoye, Stefan Hansson, Gerry Kenna, Lisbeth E. Knudsen, Udo R. Markert, Nicola Powles-Glover, Henning Schneider, Lopa Leach (2016); Reproductive Toxicology 64, pp. 191–202. doi url

• A mathematical model of intervillous blood flow in the human placentone by I. L. Chernyavsky, O. E. Jensen, L. Leach (2010); Placenta 31(1), pp. 44–52. doi url preprint

Asthma is one of the most common lung conditions that causes asthma attacks and breathlessness, affecting over 5 million people in the UK alone. Bronchial Thermoplasty (BT) is a non-pharmacological treatment for severe asthma that involves application of electro-generated heat to the lung airways. We have developed integrated theoretical and experimental models for Bronchial Thermoplasty that encompass all scales, from individual cells to organ level, to understand the impact of the treatment on lung structure and function. Our study revealed unexpected possible mechanisms of action of BT, as well as its limitations. Our approach should allow for better targeting of patient groups that could benefit most from the BT procedure, while also suggesting optimisation of treatment protocols. Please see more details on AirPROM and below.

• Comment on “Unraveling a clinical paradox: Why does bronchial thermoplasty work in asthma?” by Bindi S. Brook, Igor L. Chernyavsky, Richard J. Russell, Ruth M. Saunders, Christopher E. Brightling (2019); American Journal of Respiratory Cell and Molecular Biology 61(5), pp. 660–661. doi url preprint

• In vitro, in silico and in vivo study challenges the impact of bronchial thermoplasty on acute airway smooth muscle mass loss by Igor L. Chernyavsky, Richard J. Russell, Ruth M. Saunders, Gavin E. Morris, Rachid Berair, Amisha Singapuri, Latifa Chachi, Adel H. Mansur, Peter H. Howarth, Patrick Dennison, Rekha Chaudhuri, Stephen Bicknell, Felicity R. A. J. Rose, Salman Siddiqui, Bindi S. Brook, Christopher E. Brightling (2018); European Respiratory Journal 51(5), pp. 1701680. doi url preprint

This project quantified the uncertainty in long-term structural changes (remodelling) of an airway wall in asthma due to inflammation-driven smooth muscle mass accumulation. Inflammation is described as a temporal stochastic process, driven by a series of random inflammatory stimuli, which is coupled to a population growth model. In the paper with Brook et al. (PLoS ONE 2014), we demonstrated, by means of asymptotic techniques and Monte-Carlo simulations, the significant impact of the inflammation resolution rate both on the expected long-term outcome and on the prediction uncertainty.

• The role of inflammation resolution speed in airway smooth muscle mass accumulation in asthma: insight from a theoretical model by Igor L. Chernyavsky, Huguette Croisier, Lloyd A. C. Chapman, Laura S. Kimpton, Jonathan E. Hiorns, Bindi S. Brook, Oliver E. Jensen, Charlotte K. Billington, Ian P. Hall, Simon R. Johnson (2014); PLoS ONE 9(3), pp. e90162. doi url preprint

In this series of works with Jensen et al., we addressed the effective macroscopic description of solute transport across multiple scales in regular and irregular geometries (e.g. arrays of point sinks), exploring possible transport regimes and the accuracy of an averaged description of the underlying random microstructure. Our research has shown a surprisingly strong impact of the solute fluctuations on the global transport dynamics in certain parameter regimes. These results open several interesting avenues of research that warrant further study.

• Advection-dominated transport past isolated disordered sinks: stepping beyond homogenization by George F. Price, Igor L. Chernyavsky, Oliver E. Jensen (2022); Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 478(2262), pp. 20220032. doi url preprint

• Characterizing the multiscale structure of fluctuations of transported quantities in a disordered medium by Igor L. Chernyavsky, Ian L. Dryden, Oliver E. Jensen (2012); IMA Journal of Applied Mathematics 77(5), pp. 697–725. doi url preprint

• Transport in the placenta: homogenizing haemodynamics in a disordered medium by Igor L. Chernyavsky, Lopa Leach, Ian L. Dryden, Oliver E. Jensen (2011); Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369(1954), pp. 4162–4182. doi url preprint

Underground hydrogen storage is emerging as a pivotal solution in the transition to a sustainable energy economy. This project aims to enhance the operational robustness and efficiency of this technology. We utilise mathematical modelling and uncertainty quantification approaches, which are informed by advanced imaging techniques that span nano- to macro-scales.

We have been studying the coupling of active and passive transport of microscopic vesicles critical for the cell growth, using the rapidly growing (up to 1 cm/h) pollen tube as a model system. In the study with Geitmann et al. (Nottingham 2010), we have shown the impact of the cell geometry and the rate of active transport by cytoskeletal network on the distribution of the vesicles. This problem has been further pursued theoretically and experimentally in Cambridge at the Ray Goldstein's biophysical lab (Cambridge 2012), and the work to understand the response of a growing cell to external fields and mechanical stresses continues, in collaboration with the strong magnetic field group of Laurence Eaves in Nottingham.

• Some aspects of pollen tube growth in a creeping flow by I. L. Chernyavsky, V. Kantsler, R. E. Goldstein (2012); In Biological Flows Meeting: A Conference to Celebrate the 70th Birthday of Prof. Timothy J. Pedley. pp. 15. Cambridge. url preprint

• Intracellular dynamics of secretory vesicles in the tip of growing pollen tubes by L. R. Band, I. L. Chernyavsky, R. J. Dyson, F. Z. Nouri, B. Piette, A. Geitmann (2010); Nottingham. url

This work, with Kudryashov (Fluid Dyn. 2008), proposed a new theoretical model that dynamically couples fluid shear stress and muscle tone regulation in blood vessels via a biochemical feedback mechanism. The model explained how an artery can adapt to changing flow conditions and predicted various experimentally observed oscillatory regimes.

• Numerical simulation of the process of autoregulation of the arterial blood flow by N. A. Kudryashov, I. L. Chernyavsky (2008); Fluid Dynamics 43(1), pp. 32–48. doi url preprint

In this study, with Kudryashov (Fluid Dyn. 2006), we obtained a set of effective evolution equations for small-but-finite-amplitude nonlinear waves in a viscoelastic tube that account for various structural components of a blood vessel. Wall viscosity was shown to be important for damping high-frequency oscillations. In addition, we proposed a classification of different vascular mechanical parameters with respect to the dominating spatio-temporal scales.

• Nonlinear waves in fluid flow through a viscoelastic tube by N. A. Kudryashov, I. L. Chernyavsky (2006); Fluid Dynamics 41(1), pp. 49–62. doi url preprint