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Visuals

Animations

Growth of a biofilm of the bacteria <i>Bacillis subtilis</i> over four days.
Biofilm Growth
Growth of a biofilm of the bacteria Bacillis subtilis over four days.
Animation on Bragg Peak, the peak of energy release at the site of the tumor.
Bragg Peak
When energetic protons enter tissue, they release most of their energy as they come to rest. Damage to nearby organs and structures can be minimized.
A population of slime-mold cells forms an aggregate in response to a signaling molecule.
Chemotaxis
A population of slime-mold cells forms an aggregate in response to a signaling molecule.
Cyclotron
Cyclotron
At the center of a cyclotron, a charged particle travels through a magnetic field that curves its path into a spiral and out of the cyclotron at a high speed.
DNA Helix Animation
DNA Helix Animation
The double helix.
Random motion of gas molecules
Random Motion
Random motion of gas molecules—bottom up.
Rotational Entropy
Rotational Entropy
Rotational entropy is related to the number of possible ways particles can be arranged in a structure. The greater the number, the greater the entropy.
Vibrational Entropy
Vibrational Entropy
There are different kinds of entropy. Vibrational entropy describes the number of ways that a structure can flex or vibrate without breaking.
Virus Self-Assembly
Virus Self-Assembly
In some viruses the capsid appears to be completely self-assembled. Understanding capsid self-assembly could present new ways to fight disease.

Photographs

The left panel shows the projected image of students and professors who participated in the project, and the right panel shows t
Bacterial Photo
The left panel shows the projected image of students and professors who participated in the project, and the right panel shows the bacterial photo.
Rainbow images showing individual neurons fluorescing in different colors.
Brainbow
Rainbow images showing individual neurons fluorescing in different colors. By tracking the neurons through stacks of slices, we can follow each neuron's complex branching structure to create the treelike structures.
Photograph of Galapagos finches
Darwin's Finches
The variation in Galapagos finches inspired Charles Darwin's thinking on evolution, but may evolve too fast for his theory.
An egg
Egg
A chicken egg. Is it alive or dead?
Photograph of Phineas Gage
Gage, Phineas
In 1848, a steel rod shot through the left cheek the Phineas Gage and exited through the top of his head. Gage never lost consciousness and lived another 13 years.
Photograph of glass heating in an oven
Glass
As a glass cools, the viscosity increases so rapidly that the atoms get frozen in a disordered state.
Ruby-throated hummingbird
Hummingbird
Ruby-throated hummingbird
photograph of polarized light through corn syrup showing a rainbow of colors
Polarized Light Through Corn Syrup
As polarized light passes through corn syrup, which is full of right-handed sugar molecules, its plane of polarization is rotated.
Rubik's Cube
Rubik's Cube
A Rubik's Cube is a familiar example of a hierarchical distribution of states.
Cartilage from the fin of the Mako shark.
Shark Cartilage
Cartilage from the fin of the Mako shark.
Colored smoke marks the hydrodynamic flow around the wing of an aircraft
Wake Vortex
Colored smoke marks the hydrodynamic flow around an aircraft, an emergent phenomenon.

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Graphics

This sequence logo is a compact way of displaying information contained in a piece of genetic material.
Binding Site Logo
This sequence logo is a compact way of displaying information contained in a piece of genetic material.
A schematic view of what constitutes a complex adaptive system.
Complex Adaptive Behavior
A schematic view of what constitutes a complex adaptive system.
Schematic of a modern digital computer.
Computer Schematic
Schematic of a modern digital computer.
The DNA double helix, in three of its possible configurations.
DNA Configurations
The DNA double helix, in three of its possible configurations.
Two possible paths across an energy landscape strewn with local minima.
Energy Landscape
Here, we see two possible paths across an energy landscape strewn with local minima.
The picture here shows two different enzymes (purple) that read and replicate the DNA molecule (multi-colored).
Enzymes
The enzyme on the left has a much easier time reading DNA than the enzyme on the right due to structural details that are difficult to predict from first principles.
Natural selection can be viewed as movement on a fitness landscape.
Fitness Landscape
Natural selection can be viewed as movement on a fitness landscape.
This simple system of three spins is frustrated, and has no clear ground state.
Frustrated Spin System
This simple system of three spins is frustrated, and has no clear ground state.
The structure of myoglobin on the left and the form it actually takes in space on the right.
Myoglobin
The structure of myoglobin (left) and the form it actually takes in space (right).
Natural selection and fitness
Natural Selection
Sewall Wright sketched the path different populations might take on the fitness landscape.
Two possible conformations of a prion protein: on the left as a beta sheet; on the right as an alpha helix.
Prion Structures
Two possible conformations of a prion protein: on the left as a beta sheet; on the right as an alpha helix.
A schematic of how minimizing the free energy of a molecule could lead to protein folding.
Protein Folding Funnel
A schematic of how minimizing the free energy of a molecule could lead to protein folding.
The circuit diagram (top), bacterial population (center), and plot of the dynamics (bottom) of the repressilator, an example of
Repressilator
The circuit diagram (top), bacterial population (center), and plot of the dynamics (bottom) of the repressilator, an example of a simple synthetic biological network.
The chemical structure of RNA (left), and the form the folded molecule takes (right).
RNA
The chemical structure of RNA (left), and the form the folded molecule takes (right).
RNA and DNA
RNA and DNA
Molecules of life: RNA (left) and DNA (right).
Map of Germany with a line showing the optimal path for a traveling salesman
Traveling Salesman Problem
An optimal travelling salesman problem (TSP) tour through Germany's 15 largest cities. It is the shortest among 43,589,145,600 possible tours visiting each city exactly once.
Turing test: To address the question of whether machines can show the kind of intelligence that humans possess.
Turing Test
Player C is trying to determine which player—A or B—is a computer and which is a human.