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Nobel Prizes 2014

Science Fields

Physics prize to scientists who transformed lighting

The 2014 Nobel Physics Prize was awarded to two Japanese and a Japan-born US scientists who engineered the elusive blue light-emitting diodes (LEDs) which paved the way for the development of now-ubiquitous bright white light sources , the tiny, energy saving white LEDs which have become an unseparable part of our daily lives.  

The statement issued by the Nobel Committee said  Japanese physicists Isamu Akasaki, Hiroshi Amano and (US citizen) Shuji Nakamura were honored "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources."

Being the indispensable component of myriad gadgets and applications, from television screens to liquid crystal displays of computers and hand-held devices; from car headlines to remote controls, chief advantage of LEDs are  their low and  efficient consumption of energy. In standard incandescent lamps, light is produced by a thin wire, generally of tungsten, which heats up because of its resistivity of electric current passing through it. But most of the electromagnetic energy is wasted as heat. LEDs, however, emit photons (light) via the flow of electrons on a two-head semiconductor with “p” (positive) and “n” (negative) sections, dominated, respectively, by holes and electrons. An LED, producing light equal to that produced by a 40-Watt incandescent  bulb by using a mere 4-5 Watts of power, has a life span of 50.000 hours compared to theaverage  1200 of ordinary bulbs. 

Shuji Nakamura (left)  Isamu Akasaki (center) and  Hiroshi Amano (right) were awarded Nobel Physics Prize.

White light is produced by the mixing of red, green and blue lights, each with different energies (wavelengths) . Whereas red and Green LEDs, emitting light in shorter wavelengths, had been developed in 1950s and 1960s, initial versions of the blue LEDs required to complete the trio could be developed only in late 1980s and early 1990s by the three Nobel laureates working independently. The feat was made possible by the development of gallium nitrite (GaN) based semiconductors with far larger band gaps, which were later doped with impurities  to boost their efficiency. Finally, in 1993, Nakamura who completed his education in Japan and later was employed at the UC Santa Barbara, developed the first blue LED which provided light with sufficient brightness. 

Chemistry Prize to super-resolved microscopy

2014 Nobel Chemistry Prize was shared by (left to right) Eric Betzig, Stefan W. Hell ve William E. Moerner

The statement by the Royal Swedish Academy of Sciences said the 2014 Nobel Chemistry Prize was awarded jointly to American scientists Eric Betzig (Howard Hughes Medical Institute), William E. Morner (Stanford University) and Stefan W. Hell of the Max Planck Institute for Biophysical Chemistry and German Cancer Research Center “for  the development of super-resolved fluorescence microscopy”. The technique which bagged the prestigious prize for the researchers  enables the 3-D imaging of the nano-scale individual molecules within the cells. 

Brain GPS navigates to Physiology and Medicine Prize

The Nobel Committee awarded the 2014 Physiology and Medicine Prize to researchers of two distinct generations "for their discoveries of cells that constitute a positioning system in the brain". The committee awarded half of the prize to John O’Keefe of the University College London  and the other half to a Norwegian scientist couple, who, after briefly working in his lab, moved on to Norway’s Science and Technology University to make their own discovery which completed the picture.

John O’Keefe (left) and Norwegian couple May-Britt and Edvard Moser shared the 2014 Nobel Prize for Physiology and Medicine

During his experiments with rats in 1970s, O Keefe observed that a cell at a specialized region called hippocampus in the brains of animals was getting activated whenever the rat came on the same spot as it paced the room. Some other neurons of the same type were also firing at certain spots on the rat’s path. O’Keefe named these “place cells” . After exploring a new place these groups of cells could form a mental chart of the place.

Thirty years later, Norwegian couple May-Britt and Edvard Moser discovered that another group of cells at another brain area called entorhinal cortex were activated at regular intervals during the course of the exploration. These, which the researchers dubbed “grid cells”, were seen to be forming a coordinate system together with the “place cells”. Thanks to the mental GPS chart formed by these cells , we can tell where we are and recognize when we see it again later. 

REFERENCES

  • 1. http://www.nobelprize.org/nobel_prizes/lists/year/?year=2014
  • 2. http://theconversation.com/nobel-prize-in-medicine-decades-of-work-on-the-brains-gps-recognised-32580