Nobels go to maps, LEDs, microscopy

As if to recognize that walls separating scientific fields are falling, the 2014 Nobel Prizes in chemistry, physics and physiology or medicine went to discoveries that defy single-discipline labels.

“Biology has turned into chemistry. Chemistry has turned into biology,” says Sven Lidin, chairman of the chemistry Nobel committee. This year’s chemistry laureates developed microscopy techniques that allow researchers to peer into the depths of cells, watch neurons shift shapes in learning brains and glimpse clumped-together proteins in diseases such as Alzheimer’s, Huntington’s and Parkinson’s (SN: 6/15/13, p. 20).

In 2000, chemistry winner Stefan Hell of Germany’s Max Planck Institute for Biophysical Chemistry and colleagues shot lasers at fluorescent molecules. The first laser lit up a wide group of molecules while a second laser with a doughnut-shaped beam knocked out the glow of any molecules in its path. This left a tiny circle in which scientists could observe molecules in action.

To peer inside cells, chemistry winners Eric Betzig of the Howard Hughes Medical Institute and W.E. Moerner of Stanford University engineered light switches for molecules.

In 1997, Moerner and colleagues reported that zapping fluorescent molecules with different wavelengths could cause individual molecules to light up or black out. In 2006, Betzig and colleagues used similar molecules to view a lone membrane protein from a mammalian cell. The method, he says, could “tell us how inanimate molecules come together to create animate life.”

Researchers in neuroscience won the Nobel Prize in physiology or medicine for figuring out how a rat’s brain keeps track of the animal’s location. In 1971, John O’Keefe of University College London found that certain cells in the rat hippocampus, a brain region involved in memory, became active only when an animal was in particular spots. These “place cells” allowed an animal to form an internal map of its surroundings.

More than three decades later, May-Britt Moser and Edvard Moser, married researchers at the Norwegian University of Science and Technology, discovered what they dubbed “grid cells” in a nearby brain area, the entorhinal cortex. These cells fired off signals when a rat passed through certain locations spaced at regular intervals, becoming active in multiple locales that correspond to a hexagonal grid.

Along with other neurons, grid cells send messages to place cells, the Mosers found. This network of neurons allows an animal to know where it is.

The three laureates in physics are not physicists but engineers. They invented blue light-emitting diodes, which are central to the energy-efficient lights that illuminate homes and electronic displays.

After the discovery of red and green LEDs in the 1960s, materials emitting high-energy blue light proved difficult to create. In the late 1980s, Isamu Akasaki and Hiroshi Amano, both of Nagoya University in Japan, were studying a promising semiconductor material of gallium nitride doped with other chemicals. After dozens of engineers failed to grow high-quality gallium nitride crystals, Akasaki and Amano managed the feat in 1986 and soon made blue LEDs from them.

Shuji Nakamura, working at the same time at Nichia Chemicals, developed his own method for creating high-quality gallium nitride. That work led, by the early 1990s, to a simple and cheap way to produce blue LEDs.

The physics Nobel committee often presents awards for theories or for observing new fundamental physics phenomena. This time, the judges went for big-picture impact. Alfred Nobel “wanted his prize to be given to inventors for the benefit of mankind,” said committee member Olle Inganäs. “What we emphasize today is the usefulness of this thing.”