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Stuff(t)�(or the Protocol of Biological Dynamics)

Quantitative Biology Bootcamp

Fall 2025

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The Incredible Diversity of Time Scales in Biological Processes

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Stuff(t) Pervades All of Science�Galileo and Falling Bodies

[The universe] cannot be read until we have learnt the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometrical figures…

Galileo Galilei

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Stuff(t) Pervades All of Science�Newton, Linking Galileo and Kepler, and Falling Into Orbit

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Stuff(x,t) Pervades All of Science�The Belousov–Zhabotinsky Reaction

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Stuff(t) Pervades All of Science�Human Impacts and the Keeling Curve

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Stuff(t) Pervades All of Science�Dynamics of the Immune System

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Stuff(t) Pervades All of Science�Dynamics of Embryonic Development

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Update Rules: A Revolution Enabled by Newton

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The Step-In-Time Protocol

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Stuff(t) Pervades All of Science�Dynamics of Bacterial Growth

  • Your turn: Estimate the division time in this movie
  • What sets the time scale for bacterial division?
  • Let’s answer this question by developing a feeling for the organism!

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Neidhardt and His Lifelong Love for dN/dt

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Measuring Growth Dynamics in Bulk

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What Does This Data Tell Us?

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Bacterial Growth Dynamics Revealed the Great Insight from Monod and Jacob: Genes That Control Other Genes

Monod (1949)

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Single-Cell Bacterial Growth in High Throughput: The Mother Machine

Suckjoon Jun @ UCSD

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The Mathematics of Change

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A Model of Bacterial Growth

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A Probabilistic View of Bacterial Growth

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Probabilistic and Bulk Bacterial Growth

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A Recurring Theme: Divide and Conquer�The Example of Riemann Integrals

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Divide and Conquer in Time to Integrate Differential Equations Using the Euler Method

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Our First Key Equation: Exponential Growth

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A Feeling for Exponential Growth

  • Your turn: How long would it take for E. coli doubling every 30 minutes to cover the whole surface of the Earth?

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Logistic Growth Accounts for the Carrying Capacity of a Cell Culture

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Logistic Growth

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Measuring Colony Growth and Fitting for the Growth Rate

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Stuff(t) Leads Us to “Dynamical Systems”�Differential Equations as Update Rules

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Our First Exercise In Mathematicizing�Our Pathetic Thinking

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