Shaping bursting by electrical coupling and noise [PDF]
Biological Cybernetics Volume 106, Number 2 (2012), 67-88, 2011 Gap-junctional coupling is an important way of communication between neurons and other excitable cells. Strong electrical coupling synchronizes activity across cell ensembles. Surprisingly, in the presence of noise synchronous oscillations generated by an electrically coupled network may differ qualitatively from the oscillations produced by uncoupled ...
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Learning theories reveal loss of pancreatic electrical connectivity in diabetes as an adaptive response [PDF]
PLoS ONE 8(8): e70366 (2013), 2013 Cells of almost all solid tissues are connected with gap junctions which permit the direct transfer of ions and small molecules, integral to regulating coordinated function in the tissue. The pancreatic islets of Langerhans are responsible for secreting the hormone insulin in response to glucose stimulation.
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The effects of beta-cell mass and function, intercellular coupling, and islet synchrony on $\textrm{Ca}^{2+}$ dynamics [PDF]
, 2020 Type 2 diabetes (T2D) is a challenging metabolic disorder characterized by a substantial loss of $\beta$-cell mass and alteration of $\beta$-cell function in the islets of Langerhans, disrupting insulin secretion and glucose homeostasis. The mechanisms for deficiency in $\beta$-cell mass and function during the hyperglycemia development and T2D ...
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A Local Counter-Regulatory Motif Modulates the Global Phase of Hormonal Oscillations [PDF]
, 2016 Counter-regulatory elements maintain dynamic equilibrium ubiquitously in living systems. The most prominent example, which is critical to mammalian survival, is that of pancreatic {\alpha} and {\beta} cells producing glucagon and insulin for glucose homeostasis.
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Beneficial effects of intercellular interactions between pancreatic islet cells in blood glucose regulation [PDF]
, 2009 Glucose homeostasis is controlled by the islets of Langerhans which are equipped with alpha-cells increasing the blood glucose level, beta-cells decreasing it, and delta-cells the precise role of which still needs identifying. Although intercellular communications between these endocrine cells have recently been observed, their roles in glucose ...
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On the coherent behavior of pancreatic beta cell clusters [PDF]
, 2014 Beta cells in pancreas represent an example of coupled biological oscillators which via communication pathways, are able to synchronize their electrical activity, giving rise to pulsatile insulin release. In this work we numerically analyze scale free self-similarity features of membrane voltage signal power density spectrum, through a stochastic ...
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Représentations banales de GL(m,D) [PDF]
Compositio Math. 149 (2013) 679-704, 2011 Soit F un corps commutatif localement compact non archim\'edien de caract\'eristique r\'esiduelle p, soit D une F-alg\`ebre \`a division centrale de dimension finie et soit R un corps alg\'ebriquement clos de caract\'eristique diff\'erente de p. Nous d\'efinissons la notion de R-repr\'esentation irr\'eductible banale de G=GL(m,D), notion qui g\'en ...
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Self-assembly, Buckling & Density-Invariant Growth of Three-dimensional Vascular Networks [PDF]
arXiv, 2019 The experimental actualisation of organoids modelling organs from brains to pancreases has revealed that much of the diverse morphologies of organs are emergent properties of simple intercellular "rules" and not the result of top-down orchestration. In contrast to other organs, the initial plexus of the vascular system is formed by aggregation of cells
arxiv
Modeling of reaction-diffusion transport into a core-shell geometry [PDF]
arXiv, 2018 Fickian diffusion into a core-shell geometry is modeled. The interior core mimics pancreatic Langerhan islets and the exterior shell acts as inert protection. The consumption of oxygen diffusing into the cells is approximated using Michaelis-Menten kinetics. The problem is transformed to dimensionless units and solved numerically.
arxiv
Familles de polynomes liees aux courbes modulaires X_1(l) unicursales et points rationnels non-triviaux de courbes elliptiques quotient [PDF]
, 2003 Soit l un entier et E_{c,l} la famille de Kubert des courbes elliptiques definies sur Q munies d'un point rationnel A d'ordre l. On note F_{c,l} la courbe elliptique quotient de E_{c,l} par le groupe engendre' par A, et f_l l'isogenie de E_{c,l} sur F_{c,l}.
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