Research HighlightsResearch
October 2023 Issue
Turing patterns go nano
The formation of certain patterns in nature, such as particular animal skin stripes or spots, can be explained by means of reaction–diffusion theory. This formalism, developed by Alan Turing, is based on the presence of two components (called ‘activator’ and ‘inhibitor’) with different diffusion rates. These two-component situations can give rise to what is collectively known as Turing patterns, such as the stripes seen on the skin of tropical fish or emerging order in chemical systems. Typical length scales of biological Turing patterns range from millimetres to centimetres. For purely chemical systems, the characteristic lengths are usually sub-millimetre. Although reaction–diffusion theory does not pose limits on intrinsic length scales, Turing patterns on the nanometre scale are rare. Recently, however, Yuki Fuseya from the University of Electro-Communications, Tokyo, and colleagues have identified a new type of nanoscale Turing patterns in a monolayer of bismuth atoms on a substrate.
Impact of the largest Gamma-Ray Burst on the Earth’s ionosphere
Satellites detect gamma-ray bursts most days but rarely do these events affect the ionosphere. However, when they do, they have a measurable impact on the propagation of Low Frequency (LF) and Very Low Frequency (VLF) radio waves there. Now researchers led by Yasuhide Hobara at the University of Electro-Communications have examined the impact of the Gamma-Ray Burst GRB221009A, which took place on 9th October 2022 and is the largest detected gamma-ray burst ever recorded on Earth. They reported their results in the journal Atmosphere on 20th January 2023.