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Updated: Jun 25, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Dynamic stability versus thermodynamic performance in a simple model for a Brownian motor.
Moisés Santillán1, Michael C Mackey
1Centro de Investigación y Estudios Avanzados del IPN, Unidad Monterrey, Parque de Investigación e Innovación Tecnológica, 66600 Apodaca NL, Mexico. msantillan@cinvestav.mx
Summary
This study introduces a Brownian motor model to understand how living systems maintain optimal conditions (homeostasis). It reveals insights into the energetic costs of achieving stability and rapid responses, crucial for cellular processes.
Area of Science:
- Biophysics
- Systems Biology
- Theoretical Biology
Background:
- Homeostasis enables organisms to function optimally amidst environmental changes.
- The stability of a homeostatic state is assessed by its basin of attraction and relaxation time.
- Intracellular processes, predominantly enzymatic, can be modeled using principles similar to Brownian motors.
Purpose of the Study:
- To introduce a simple Brownian motor model for studying intracellular processes.
- To investigate the relationship between efficiency and stability in biological systems.
- To analyze the energetic costs associated with maintaining homeostasis.
Main Methods:
- Analysis of the existence, uniqueness, and stability of the Brownian motor's steady state.
- Study of thermodynamic process variables and their parameter dependence.
- Comparison of Brownian motor relaxation times with thermodynamic properties.
Main Results:
- The developed Brownian motor model exhibits a unique and globally stable steady state.
- Analysis provides insights into the interplay between efficiency and stability.
- Thermodynamic properties and relaxation times were characterized and compared.
Conclusions:
- The unique and stable steady state of the Brownian motor model offers a framework for understanding cellular homeostasis.
- Results highlight the energetic trade-offs in maintaining rapid and stable cellular functions.
- The model contributes to understanding the energetic costs of achieving short relaxation times for homeostatic states.
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