Category Archives: Systems Theory

How do I change the simulation tolerances in Tellurium?

For very complicated and large models it may be necessary to adjust the simulator tolerances in order to get the correct simulation results. Sometimes the simulator will terminate a simulation because it was unable to proceed due to numerical errors. … Continue reading

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How do I plot phase plots using Tellurium?

Phase plots are a common way to visualize the dynamics of models where time courses are generated and one variable is plotted against the other. For example consider the following model that can show oscillations: v1: $Xo -> S1; k1*Xo; … Continue reading

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How to get the Stoichiometry Matrix using Tellurium

Here is a simple need, given a reaction model how do we get hold of the stoichiometry matrix? Consider the following simple model: import tellurium as te import roadrunner r = te.loada(“”” $Xo -> S1; k1*Xo; S1 -> S2; k2*S1; … Continue reading

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How to do a simple simulation using Telluirum

The most common requirement is the ability to carry out a simple time course simulation of a model. Consider the model:     Two reactions and three metabolites, S1, S2 and S3. We can describe this system using an Antimony … Continue reading

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Bode Plots using Python

I needed a quick way to plot some Bode plots for a second order system. I didn’t have access to Matlab, instead I searched for a solution using Python, and I found one. Documentation is a bit sparse  so this … Continue reading

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Skynet Edges Closer

There is a fascinating article in science this week about the construction in hardware of a neural chip. This isn’t a new idea but scale and flexibility is novel. The chip is made by researchers from IBM and Cornell and can … Continue reading

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Reversibility and Product Inhibition

It is common in biochemistry to categorize reactions as either reversible or irreversible. What do we mean by these terms? Let’s look at a simple reaction such as:     where A is transformed to B. The rate of reaction … Continue reading

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Synthetic Biology: It’s an analog world

I significant paper on synthetic biology got published this week by an innovative group from MIT (Daniel et al). Read our News and Views article that discusses the importance of the paper.

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Linear Dynamics Application

There are a number of online apps that can show students the phase plane dynamics of a 2d system. Notable examples include: Phase Portrait Viewer from the d’Arbeloff Interactive Math Project – requires Java installed Wolfram Phase Portrait Viewer – … Continue reading

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Choke points, Load points, Hots spots and Key steps

Choke points, load points, hot spots, key steps and critical steps are some of the many phrases that have been coined to describe places in a biochemical network where perturbations are said to make a difference. Locating these places is … Continue reading

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