# Anita T. Layton

- Robert R. & Katherine B. Penn Professor of Mathematics
- Professor in the Department of Mathematics
- Professor of Biomedical Engineering (Secondary)
- Professor in Medicine (Secondary)

**External address:**213 Physics Bldg, Durham, NC 27708

**Internal office address:**Box 90320, Durham, NC 27708-0320

**Phone:**(919) 660-6971

### Research Areas and Keywords

##### Biological Modeling

##### Computational Mathematics

##### PDE & Dynamical Systems

**Mathematical physiology.** My main research interest is the application of mathematics to biological systems, specifically, mathematical modeling of renal physiology. Current projects involve (1) the development of mathematical models of the mammalian kidney and the application of these models to investigate the mechanism by which some mammals (and birds) can produce a urine that has a much higher osmolality than that of blood plasma; (2) the study of the origin of the irregular oscillations exhibited by the tubuloglomerular feedback (TGF) system, which regulates fluid delivery into renal tubules, in hypertensive rats; (3) the investigation of the interactions of the TGF system and the urine concentrating mechanism; (4) the development of a dynamic epithelial transport model of the proximal tubule and the incorporation of that model into a TGF framework.

**Multiscale numerical methods.** I develop multiscale numerical methods---multi-implicit Picard integral deferred correction methods---for the integration of partial differential equations arising in physical systems with dynamics that involve two or more processes with widely-differing characteristic time scales (e.g., combustion, transport of air pollutants, etc.). These methods avoid the solution of nonlinear coupled equations, and allow processes to decoupled (like in operating-splitting methods) while generating arbitrarily high-order solutions.

**Numerical methods for immersed boundary problems.** I develop numerical methods to simulate fluid motion driven by forces singularly supported along a boundary immersed in an incompressible fluid.

Layton, AT, Bowen, M, Wen, A, and Layton, HE. "Feedback-mediated dynamics in a model of coupled nephrons with compliant thick ascending limbs." *Math Biosci* 230.2 (April 2011): 115-127.
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Chen, J, Sgouralis, I, Moore, LC, Layton, HE, and Layton, AT. "A mathematical model of the myogenic response to systolic pressure in the afferent arteriole." *Am J Physiol Renal Physiol* 300.3 (March 2011): F669-F681.
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Layton, AT, Savage, NS, Howell, AS, Carroll, SY, Drubin, DG, and Lew, DJ. "Modeling vesicle traffic reveals unexpected consequences for Cdc42p-mediated polarity establishment." *Curr Biol* 21.3 (February 8, 2011): 184-194.
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Layton, AT. "A mathematical model of the urine concentrating mechanism in the rat renal medulla. I. Formulation and base-case results." *Am J Physiol Renal Physiol* 300.2 (February 2011): F356-F371.
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Layton, AT. "A mathematical model of the urine concentrating mechanism in the rat renal medulla. II. Functional implications of three-dimensional architecture." *Am J Physiol Renal Physiol* 300.2 (February 2011): F372-F384.
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Layton, AT, Savage, NS, Howell, AS, Carroll, SY, Drubin, DG, and Lew, DJ. "Modeling vesicle traffic reveals unexpected consequences for Cdc42p-mediated polarity establishment." *Curr Biol* 21 (2011): 1-11. (Academic Article)

Layton, AT. "A mathematical model of the urine concentrating mechanism in the rat renal medulla: I. Formulation and base-case results." *Am J Physiol Renal Physiol* 300.F356-F371 (2011). (Academic Article)

Layton, AT. "A mathematical model of the urine concentrating mechanism in the rat renal medulla: II. Functional implications of three-dimensional architecture." *Am J Physiol Renal Physiol* 300.F372-F384 (2011). (Academic Article)

Dantzler, WH, Pannabecker, TL, Layton, AT, and Layton, HE. "Urine concentrating mechanism in the inner medulla of the mammalian kidney: role of three-dimensional architecture." *Acta physiologica (Oxford, England)* 202.3 (2011): 361-378.
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Layton, AT, and Layton, HE. "Countercurrent multiplication may not explain the axial osmolality gradient." *Am J Physiol Renal Physiol* 301 (2011): F1047-F1056. (Academic Article)