Advanced MRI brain scan
Advanced MRI brain scan. This 3D magnetic resonance imaging (MRI) scan of a normal human brain has been produced by the 3T MRI scanner at Neurospin, one of the most advanced MRI research centres in the world. The front of the brain is at left. The coloured lines indicate the many neural pathways that exist in the brain. Neurospin has 3T and 7T scanners. The 'T' designations refer to the magnetic field strengths of 3 Tesla and 7 Tesla. These are extremely strong magnetic fields, and hence this technique is known as ultra high-field magnetic resonance imaging. The high magnetic field strength allows detailed examination of the brain and brain disorders. Neurospin was founded in 2006, and is located near Paris, France.
© Philippe Psaila/Science Photo Library
Colour wheel. A colour wheel is a representation of the primary, secondary and tertiary colours. This colour wheel is based on blue, red and yellow (primary colours). The primary colours are mixed to make secondary colours (green, orange and violet). The tertiary colours are created by mixing the secondary colours. These are: red-orange, red-violet, yellow-orange, yellow-green, blue-violet and blue-green.
© SCIENCE PHOTO LIBRARY
Tourmaline mineral, light micrograph
Tourmaline mineral. Polarised light micrograph of tourmaline crystals. This pattern is caused by the simultaneous crystallisation of two or more minerals in a melt at a certain temperature (the eutectic point) during cooling. This image has been obtained using cross-polarised light (or 'crossed nichols').
© DIRK WIERSMA/SCIENCE PHOTO LIBRARY