Use these tutorials to introduce quantitative sciences perspectives to your biological work. You can use this curriculum to prepare for introductory courses in undergraduate math, science, and systems biology. Know how to explain the canonical model for protein dynamics when it appears on the first day of systems biology 101. Understand why some systems of interacting molecules oscillate. Know how to estimate uncertainties and perform curve fitting. Know the difference between a normal and log-normal distribution and which is more intuitively expected in biology. If you find these tutorials helpful, these external resources and textbooks might interest you as well.
Pre-algebra, algebra, geometry, and precalculus
| Topic | Slides | Video | Description |
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| "What is a number?" |
Street numbers, money in bank accounts, points on number lines, quantum particles as contrasted with distinguishable manipulatives For our purposes, infinity is not a number |
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| Algebra |
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Variables: At once arbitrary, yet specific and particular (a.s.a.p.) Functions, composition, and inverse f(x) is not a function. f(x) is not the function f. f(x) is the particular value associated, in the big picture of the function f, with x, a number that is at once arbitrary, yet particular and specific Inverse functions do not always exist First glimpse at the complex plane and i := √ -1 Additional activity for this module |
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| Quadratic equation |
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Linear combination of terms in a polynomial Zeroes or "roots" of a function Completing the square |
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| Euclidean geometry and trigonometry |
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Flat space, curved space, non-embedded curved space Pythagorean theorem (ca. 300 BCE) The unit-radius circle, the unit-hypotenuse triangle, jya-ardha (sine), koti-jya (cosine) (ca. 510) Geometric construction for approximating π Angle-sum identities Additional activity for this module |
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| Summation |
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Geometric series Harmonic series; sums do not always exist Gauss summation trick |
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| Enumerative combinatorics |
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Permutations and factorials Combinations Binomial theorem Small parameter expansion |
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Calculus (ca. 1700s)
In this unit we define constructions in calculus (derivatives and integrals) so that we can eventually identify them, using explicit and concrete figures and words, with the processes of (1) describing the kinetic processes and (2) inferring long-term time-course outcomes for collections of chemically reacting biological molecules. This line of discussion presents differential equation models of biology as potentially useful approximations. Biochemistry is not always idiomatic for calculus; in fact, cellular biochemistry is an example of where applying calculus can be very dicey.
| Limits |
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ε-δ definition of limit, notion of "arbitrarily close" Example of calculating a limit Limits do not always exist |
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| Taylor expansions II |
l'Hôpital's rule ("0/0" version) Newton-Raphson method for approximating zeros of a function |
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| Integration II | Integration by parts |
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| Integration III |
Integrals do not always exist Triangle/trigonometric substitution Partial fractions |
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| Euler's number projects day |
Make a slide rule Equal-tempered tuning in European musical tradition |
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Non-dimensionalization
| Stochasticity |
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(This section is a prerequisite for "protein dynamics 101"). Many of the homework problems from undergraduate calculus and differential equations involve notions of stochasticity. * For-real stochasticity: Fundamental indeterminism * Fake stochasticity: Periodic, deterministic hidden variables * Fake stochasticity: Aperiodic, deterministic (chaos) Markov models Additional activity for this module |
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| Mass action |
Why mass action reaction rates look like terms from polynomials Cooperativity of the simple kind Hill functions |
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| Gompertzian dynamics | PDF notes |
A given trajectory can often be easily accommodated by a variety of physically inconsistent microscopic models Derivation from time-invariant, resource-limited governing equation Derivation from time-variant governing equation Negative sign floating around in Gompertzian age distribution (1825) |
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Linear algebra
| LA I |
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Motivating example: Modeling dynamics of web start-up company customer base Vector space and basis Linear operator and representation Matrix multiplication Using eigenvalues and eigenvectors to avoid computational inefficiency Additional activity for this module |
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| Euler's number II |
Small-argument expansion Euler's formula: Expanding the exponential function in terms of sine and cosine |
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| LA II |
Euclidean rotation matrix Complex eigenvectors and eigenvalues |
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| LA III |
Orthogonality, dot product, and length Determinants Invertibility Euclidean rotation matrix |
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| Quasispecies | Simple quasispecies eigendemographics and eigenrates |
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Differential equations
| DEs I |
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Direction fields, quiver plots, and integral curves Numerical integration of systems of differential equations |
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| DEs II |
Integrating factor method Solution by power-series expansion |
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| DEs III |
Eigenvector-eigenrate solution method for canonical 2-by-2 system of linear differential equations with constant coefficients Phase portrait stability analysis |
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| Transcription-translation | Canonical mRNA-protein system from systems biology 101 |
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| DEs IV |
Using linear algebra to study nonlinear differential equations Local linearization: Jacobian |
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| DEs V |
Intuitive introduction to 2-d oscillations (Romeo and Juliet) Twisting nullclines Time-delays Stochastic resonance |
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| Adaptation | Adaptation is not absence of change; instead it is the presence of eventually compensatory changes |
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| Biological oscillators |
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| Evolutionary game theory |
Replicator dynamics Prisoner's dilemma Simultaneous survival of the relatively most fit with decrease in overall fitness |
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| Additional homework | TBA |
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Ignoring small parameters (guess and check)
Fourier analysis
Example: Audio compression (irrelevance coding) on iPods and other MP3 players
Probability, statistics, and stochastic processes
| Coin toss |
Bernoulli (ca. 1700s) coin-toss process Binomial distribution |
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| Limit of rare events | Poisson distribution |
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| Luria-Delbrück fluctuation analysis | P0 method |
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| Limit of many independent parts |
Stirling's approximation Statement of central limit theorem, heuristic study of binomial distribution in limit of many coin tosses Biology's central limit theorem: Log-normal distributions |
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| Working with brackets |
Variances of independently fluctuating variables add Experimental uncertainty propagation |
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| Parameters and sample estimators |
Standard deviation vs. sample standard deviation Mean vs. sample mean Standard deviation of the mean vs. standard error of the mean |
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| Apparent sample size | "I quantitated staining intensity for 1 million cells in contiguous fields of view, everything I measure is statistically significant!" Your data quite possibly fail to meet the fine print permitting application of the √ N formula for calculating the standard error. |
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| Curve fitting |
Reduced chi-square χ2 Best-fit parameters are not independent (Gutenkunst, Sorger) |
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| Describing heterogeneity |
Why on earth have we multiple measurements of distribution heterogeneity? Some measures increase, some flatline, and some decrease with "effective number" size
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Stochastic models and their implementation in MatLab
| Master equation and SSA |
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Interpretation of master equation Derivation of exponential distribution of waiting times |
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| Numerical stochastic simulation |
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Pseudo-random number generators Example stochastic birth-death process script |
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| Langevin integration method |
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Stochastic differential equations Gaussian white noise |
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| Path integrals |
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Spatially-resolved models
| Fast-Fourier transform |
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| Efficient computation of local linear interactions | FFT convolution trick |
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Newtonian physics
| Vectors | Review of vector addition and vector calculus |
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| Force |
Velocity v := dx/dt Momentum p := mv Momentum exchange for an isolated pair of bodies Superposition of pairwise momentum exchange FNET = ma |
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| Newtonian gravitation |
r2-law Approximate uniform gravitational acceleration for small relative changes in radii |
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| Uniformly accelerated motion |
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| Non-fundamental forces |
Normal force Tension Kinetic and static friction |
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Simple-harmonic-oscillation (pendulum)
| Lab: Measuring the gravitational field with a pendulum |
Elastic materials (Hookean)
Elastic modulus
Propagation of vibrations on a taut string
Standing waves
Lab: Measure the speed of sound using a flute
Lab: Build a graduated cylinder water harmonica (equal-tempered tuning)
Derivation of the shape of a suspension bridge
Lab: Calculate the linear mass-density of the Golden Gate bridge
Momentum conservation
Work and energy conservation
Newton's law of gravitation
Rocket science
Electricity and magnetism
Modern physics
Light has wave-like properties
| Lab: Location of phantom laser spots seen while wearing diffraction-grating glasses |
Postulates of quantum mechanics
Heisenberg uncertainty relationship (not a principle, but a result): You postulate that eigenvalues of Hermitian operators represent experimental measurement outcomes; you define some operators in terms of other operators in ways such that they necessarily cannot share eigenvectors, and then you are surprised that dispersion in some observables can only be squished at the expense of precision in other observables
Ehrenfest theorem and correspondence principle, Newtonian physics from quantum mechanics
Particle in a box
| Hydrogen atom | Single-electron solution |
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| Multi-electron atom |
Taylor-expansion of interaction potential See also: http://arxiv.org/abs/physics/0407126 |
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| Multi-electron molecules |
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Symmetries, conserved quantities, and extremized quantities
Path-integral formulation of quantum mechanics and wave optics, extremizing functions of path
Entanglement, Einstein-Podolsky-Rosen paradox, and Bell's inequalities
General relativity
Sine-Gordon equation and solitons
Statistical physics
| Modern statistical mechanics |
Heuristic justification of equal a priori probability postulate Second "law" of thermodynamics |
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| Boltzmann distribution |
Ways of sharing energy between a small system and a large reservoir Entropy Free energy |
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| Ising model |
Phase transition Hysteresis |
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| Bose-Einstein statistics |
Bose-Einstein systems obey Boltzmann distributions! A quantum index need not be interpreted as referring to a collection of distinct particles. Lagrange multiplier |
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Blackbody radiation
Diffusion, Brownian motion, and fluctuation-dissipation (Smoluchowski treatment)
Self-organized criticality
Chaos is not a lack of determinism
Biological physics and biophysics
Optical coherence microscopy
Fluorescence correlation spectroscopy and auto-correlation function
Lateral displacement mechanical flow cell sorter (Loutherback-Sturm)
| Introduction to population dynamics topics | See table below |
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| Fancy name | Descriptive name | Example insight |
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| Fixation time of mutants | Allele proportions fluctuate stochastically in finite populations of true-breeding replicators | Rapid loss of heterogeneity is possible in small populations |
| Quasispecies | Interplay between dispersive forces that generate genotypic heterogeneity and populating forces that favor replication of fit genotypes determine whether populations expand, maintain heterogeneity, or disperse throughout genotypic space and lose macroscopic population numbers | Fitness, in the sense of rapid net production of progeny, is not sufficient to ensure survival. It also matters whether the progeny actually look like their parents. |
| Evolutionary game theory | Collections of (mostly) true-breeding cell subpopulations interact by modulating each other's net replication rates in a pairwise, linear manner | In a population where population composition influences the absolute fitness of both relatively unfit and relatively fit subpopulations, survival of the relatively fit can lead to decline in fitness for all individuals. The rich and the poor both get poorer. |
| Cellular automata | Probabilistic or deterministic prescription for changing the discrete state of a lattice point into the future is a function of the current configuration of its local spatial neighborhood | Cell subpopulations that would otherwise die out in a well-mixed population can survive by huddling together and minimizing their interactions with hostile neighbors. Spatiality can help sustain diversity. |
