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The two-process model for sleep–wake regulation: A nonsmooth dynamics perspective (2022)
Journal Article
Şaylı, M., Skeldon, A. C., Thul, R., Nicks, R., & Coombes, S. (2023). The two-process model for sleep–wake regulation: A nonsmooth dynamics perspective. Physica D: Nonlinear Phenomena, 444, Article 133595. https://doi.org/10.1016/j.physd.2022.133595

Since its inception four decades ago the two-process model introduced by Borbély has provided the conceptual framework to explain sleep–wake regulation across many species, including humans. At its core, high level notions of circadian and homeostati... Read More about The two-process model for sleep–wake regulation: A nonsmooth dynamics perspective.

Neural fields with rebound currents: Novel routes to patterning (2021)
Journal Article
Modhara, S., Lai, Y. M., Thul, R., & Coombes, S. (2021). Neural fields with rebound currents: Novel routes to patterning. SIAM Journal on Applied Dynamical Systems, 20(3), 1596-1620. https://doi.org/10.1137/20M1364710

The understanding of how spatio-temporal patterns of neural activity may arise in the cortex of the brain has advanced with the development and analysis of neural field models. Replicating this success for subcortical tissues, such as the thalamus, r... Read More about Neural fields with rebound currents: Novel routes to patterning.

Using GAMMs to model trial-by-trial fluctuations in experimental data: More risks but hardly any benefit (2021)
Journal Article
Thul, R., Conklin, K., & Barr, D. J. (2021). Using GAMMs to model trial-by-trial fluctuations in experimental data: More risks but hardly any benefit. Journal of Memory and Language, 120, Article 104247. https://doi.org/10.1016/j.jml.2021.104247

Data from each subject in a repeated-measures experiment forms a time series , which may include trial-by-trial fluctuations arising from human factors such as practice or fatigue. Concerns about the statistical implications of such effects have incr... Read More about Using GAMMs to model trial-by-trial fluctuations in experimental data: More risks but hardly any benefit.

Neural Fields with Rebound Currents: Novel Routes to Patterning (2021)
Journal Article
Modhara, S., Lai, Y. M., Thul, R., & Coombes, S. (2021). Neural Fields with Rebound Currents: Novel Routes to Patterning. SIAM Journal on Applied Dynamical Systems, 20(3), 1596-1620. https://doi.org/10.1137/20M1364710

The understanding of how spatio-temporal patterns of neural activity may arise in the cortex of the brain has advanced with the development and analysis of neural field models. To replicate this success for sub-cortical tissues, such as the thalamus,... Read More about Neural Fields with Rebound Currents: Novel Routes to Patterning.

Calcium buffers and L-type calcium channels as modulators of cardiac subcellular alternans (2020)
Journal Article
Lai, Y. M., Coombes, S., & Thul, R. (2020). Calcium buffers and L-type calcium channels as modulators of cardiac subcellular alternans. Communications in Nonlinear Science and Numerical Simulation, 85, Article 105181. https://doi.org/10.1016/j.cnsns.2020.105181

In cardiac myocytes, calcium cycling links the dynamics of the membrane potential to the activation of the contractile filaments. Perturbations of the calcium signalling toolkit have been demonstrated to disrupt this connection and lead to numerous p... Read More about Calcium buffers and L-type calcium channels as modulators of cardiac subcellular alternans.

A master stability function approach to cardiac alternans (2019)
Journal Article
Lai, Y. M., Veasy, J., Coombes, S., & Thul, R. (2019). A master stability function approach to cardiac alternans. Applied Network Science, 4(1), https://doi.org/10.1007/s41109-019-0199-z

During a single heartbeat, muscle cells in the heart contract and relax. Under healthy conditions, the behaviour of these muscle cells is almost identical from one beat to the next. However, this regular rhythm can be disturbed giving rise to a varie... Read More about A master stability function approach to cardiac alternans.

A statistical view on calcium oscillations (2019)
Journal Article
Powell, J., Falcke, M., Skupin, A., Bellamy, T., Kypraios, T., & Thul, R. (2019). A statistical view on calcium oscillations. Advances in Experimental Medicine and Biology, 1131, 799-826. https://doi.org/10.1007/978-3-030-12457-1_32

Transient rises and falls of the intracellular calcium concentration have been observed in numerous cell types and under a plethora of conditions. There is now a growing body of evidence that these whole-cell calcium oscillations are stochastic, whic... Read More about A statistical view on calcium oscillations.

Synchrony in networks of Franklin bells (2019)
Journal Article
Sayli, M., Lai, Y. M., Thul, R., & Coombes, S. (2019). Synchrony in networks of Franklin bells. IMA Journal of Applied Mathematics, 84(5), 1001-1021. https://doi.org/10.1093/imamat/hxz023

The Franklin bell is an electro-mechanical oscillator that can generate a repeating chime in the presence of an electric field. Benjamin Franklin famously used it as a lightning detector. The chime arises from the impact of a metal ball on a metal be... Read More about Synchrony in networks of Franklin bells.

Complex patterns of subcellular cardiac alternans (2019)
Journal Article
Veasy, J., Lai, Y. M., Coombes, S., & Thul, R. (2019). Complex patterns of subcellular cardiac alternans. Journal of Theoretical Biology, 478, 102-114. https://doi.org/10.1016/j.jtbi.2019.06.016

Cardiac alternans, in which the membrane potential and the intracellular calcium concentration exhibit alternating durations and peak amplitudes at consecutive beats, constitute a precursor to fatal cardiac arrhythmia such as sudden cardiac death. A... Read More about Complex patterns of subcellular cardiac alternans.

Analysis of networks where discontinuities and nonsmooth dynamics collide: understanding synchrony (2018)
Journal Article
Yi Ming, L., Thul, R., & Coombes, S. (2018). Analysis of networks where discontinuities and nonsmooth dynamics collide: understanding synchrony. European Physical Journal - Special Topics, 227(10-11), 1251-1265. https://doi.org/10.1140/epjst/e2018-800033-y

Integrate-and-fire networks have proven remarkably useful in modelling the dynamics of real world phenomena ranging from earthquakes, to synchrony in neural networks, to cascading activity in social networks. The reset process means that such models... Read More about Analysis of networks where discontinuities and nonsmooth dynamics collide: understanding synchrony.

On the phase space structure of IP3 induced Ca2+ signalling and concepts for predictive modeling (2018)
Journal Article
Falcke, M., Moein, M., Tilunaite, A., Thul, R., & Skupin, A. (2018). On the phase space structure of IP3 induced Ca2+ signalling and concepts for predictive modeling. Chaos, 28(4), Article 045115. https://doi.org/10.1063/1.5021073

The correspondence between mathematical structures and experimental systems is the basis of the generalizability of results found with specific systems, and is the basis of the predictive power of theoretical physics. While physicists have confidence... Read More about On the phase space structure of IP3 induced Ca2+ signalling and concepts for predictive modeling.

Three-dimensional spatio-temporal modelling of store operated Ca2+ entry: insights into ER refilling and the spatial signature of Ca2+ signals (2018)
Journal Article
McIvor, E., Coombes, S., & Thul, R. (2018). Three-dimensional spatio-temporal modelling of store operated Ca2+ entry: insights into ER refilling and the spatial signature of Ca2+ signals. Cell Calcium, 73, https://doi.org/10.1016/j.ceca.2018.03.006

The spatial organisation of Orai channels and SERCA pumps within ER-PM junctions is important for enhancing the versatility and specificity of subcellular Ca2+ signals generated during store operated Ca2+ entry (SOCE). In this paper we present a nove... Read More about Three-dimensional spatio-temporal modelling of store operated Ca2+ entry: insights into ER refilling and the spatial signature of Ca2+ signals.

Networks of piecewise linear neural mass models (2018)
Journal Article
Coombes, S., Lai, Y. M., Sayli, M., & Thul, R. (2018). Networks of piecewise linear neural mass models. European Journal of Applied Mathematics, 29(Special issue 5), 869-890. https://doi.org/10.1017/S0956792518000050

Neural mass models are ubiquitous in large scale brain modelling. At the node level they are written in terms of a set of ordinary differential equations with a nonlinearity that is typically a sigmoidal shape. Using structural data from brain atlase... Read More about Networks of piecewise linear neural mass models.

A Bayesian approach to modelling heterogeneous calcium responses in cell populations (2017)
Journal Article
Tilunaite, A., Croft, W., Russell, N. A., Bellamy, T. C., & Thul, R. (2017). A Bayesian approach to modelling heterogeneous calcium responses in cell populations. PLoS Computational Biology, 13(10), Article e1005794. https://doi.org/10.1371/journal.pcbi.1005794

Calcium responses have been observed as spikes of the whole-cell calcium concentration in numerous cell types and are essential for translating extracellular stimuli into cellular responses. While there are several suggestions for how this encoding i... Read More about A Bayesian approach to modelling heterogeneous calcium responses in cell populations.

Evolution of moments and correlations in non-renewal escape-time processes (2017)
Journal Article
Braun, W., Thul, R., & Longtin, A. (in press). Evolution of moments and correlations in non-renewal escape-time processes. Physical Review E, 95, https://doi.org/10.1103/PhysRevE.95.052127

The theoretical description of non-renewal stochastic systems is a challenge. Analytical results are often not available or can only be obtained under strong conditions, limiting their applicability. Also, numerical results have mostly been obtained... Read More about Evolution of moments and correlations in non-renewal escape-time processes.

Sign changes as a universal concept in first-passage-time calculations (2017)
Journal Article
Braun, W., & Thul, R. (2017). Sign changes as a universal concept in first-passage-time calculations. Physical Review E, 95(12114), https://doi.org/10.1103/PhysRevE.95.012114

First-passage-time problems are ubiquitous across many fields of study including transport processes in semiconductors and biological synapses, evolutionary game theory and percolation. Despite their prominence, first-passage-time calculations have p... Read More about Sign changes as a universal concept in first-passage-time calculations.

Synchrony in networks of coupled nonsmooth dynamical systems: extending the master stability function (2016)
Journal Article
Coombes, S., & Thul, R. (2016). Synchrony in networks of coupled nonsmooth dynamical systems: extending the master stability function. European Journal of Applied Mathematics, 27(6), 904-922. https://doi.org/10.1017/S0956792516000115

The master stability function is a powerful tool for determining synchrony in high-dimensional networks of coupled limit cycle oscillators. In part, this approach relies on the analysis of a low-dimensional variational equation around a periodic orbi... Read More about Synchrony in networks of coupled nonsmooth dynamical systems: extending the master stability function.

Neural field models with threshold noise (2016)
Journal Article
Thul, R., Coombes, S., & Laing, C. R. (2016). Neural field models with threshold noise. Journal of Mathematical Neuroscience, 6, Article 3. https://doi.org/10.1186/s13408-016-0035-z

The original neural field model of Wilson and Cowan is often interpreted as the averaged behaviour of a network of switch like neural elements with a distribution of switch thresholds, giving rise to the classic sigmoidal population firing-rate funct... Read More about Neural field models with threshold noise.

Probabilistic encoding of stimulus strength in astrocyte global calcium signals (2015)
Journal Article
Croft, W., Reusch, K., Tilunaite, A., Russell, N. A., Thul, R., & Bellamy, T. C. (2016). Probabilistic encoding of stimulus strength in astrocyte global calcium signals. Glia, 64(4), 537-552. https://doi.org/10.1002/glia.22947

© 2016 Wiley Periodicals, Inc. Astrocyte calcium signals can range in size from subcellular microdomains to waves that spread through the whole cell (and into connected cells). The differential roles of such local or global calcium signaling are unde... Read More about Probabilistic encoding of stimulus strength in astrocyte global calcium signals.

First passage times in integrate-and-fire neurons with stochastic thresholds (2015)
Journal Article
Braun, W., Matthews, P. C., & Thul, R. (2015). First passage times in integrate-and-fire neurons with stochastic thresholds. Physical Review E, 91, Article 052701. https://doi.org/10.1103/PhysRevE.91.052701

We consider a leaky integrate--and--fire neuron with deterministic subthreshold dynamics and a firing threshold that evolves as an Ornstein-Uhlenbeck process. The formulation of this minimal model is motivated by the experimentally observed widesprea... Read More about First passage times in integrate-and-fire neurons with stochastic thresholds.