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Discoveries and Developments: How Japan Changed the World (archive)

Volume 7: Hideo Ohno "Development of Ferromagnetic Semiconductors"

The two main properties of the electron are charge and spin. These two properties have traditionally been studied separately in the field of electronics.

Hideo Ohno merged the studies of electron charge and spin to study the two properties simultaneously, establishing the field of spintronics. He went on to create a brand new material that possesses the characteristics of both a semiconductor, related to electron charge, and a magnet, related to electron spin. This new material was the magnetic semiconductor.

The unique properties of magnetic semiconductors have made it possible to produce integrated circuit systems with zero standby power consumption. It has been shown that the principles of magnetic information storage, used in hard drives today, can be applied to semiconductor integrated circuits containing magnetic semiconductors.

Integrated circuits form the basis of the information and communication tools used in society today, as well as and various industrial products,. Magnetic semiconductors, developed by Ohno, will bring about fundamental changes to these integrated circuits, meaning that they are likely to transform society itself.


Volume 6: Seiji Ogawa ”Discovery of BOLD Contrast, the Fundamental Principle of fMRI”

Functional magnetic resonance imaging, or fMRI, is a procedure for observing how the intricate functions of the human brain are affected by external stimuli.

MRI is widely known as a procedure used in hospitals to examine the brain. It produces still images of the brain’s structure, which can then be used to identify any abnormalities of the brain from an anatomical standpoint. In contrast, fMRI produces a visual representation of blood flow activity in the brain.

fMRI could not have been developed without the Blood Oxygenation Level Dependent (BOLD) contrast principle, which was discovered by Japanese scientist Seiji Ogawa. BOLD contrast enables electromagnetic phenomena associated with functional brain activity to be detected directly, something which is difficult with MRI. This discovery allowed Ogawa to pioneer a new technique for the analysis and clinical diagnosis of human brain function.

Volume 5: Shinya Yamanaka "The Study of iPS Cells"

iPS cell technology is one of the hottest topics in the field of medical science today. It is hope that induced pluripotent stem cells, or iPS cells, will revolutionize medical science by making it possible to cure diseases currently untreatable, , and by making it easier to conduct advanced research in illnesses that are currently extremely difficult to study.

The study of iPS cells is a top priority in regenerative medicine; there is fierce competition among researchers around the world to be the first to produce breakthrough results. Dr. Shinya Yamanaka of Kyoto University is one such researcher. His work on generating a new kind of pluripotent stem cell, different from embryonic stem (ES) cells, came to fruition in 2006, when he succeeded in producing pluripotent stem cells from mouse fibroblasts. This was the world’s first generation of iPS cells, and represented a groundbreaking alternative to the generation of pluripotent stem cells from embryonic cells.


Volume 4: Sumio Iijima "The discovery of carbon nanotubes and of the structural fluctuation of ultrafine gold particles"

1991 was the year that a new “dream” material was discovered—carbon nanotubes. The man behind the discovery was Sumio Iijima, a Japanese physicist working on research in observational methods using high-resolution electron microscopy.

Today, Dr. Iijima’s name is synonymous with carbon nanotubes, such was the significance of his discovery, but this best-known achievement was in fact preceded by a considerable body of work in the field of microscopy.

It could be said, perhaps, that the carbon nanotube crystals discovered by Dr. Iijima were merely the crystallization of this outstanding researcher’s many years of cutting-edge research in microscopy.


Volume 3: Shizuo Akira "Toll-like receptors and innate immunity research"

Dr. Shizuo Akira is a formidable academic, producing some of the world’s most oft-cited research. His work boasted the highest number of total citations in 2006 and 2007, and as of 2010, his research has been cited more than 67,000 times in total (reported by Thomson Scientific Research).

Dr. Akira is a specialist research in the field of innate immunity, a previously somewhat neglected field of immunology. In particular, his research has demonstrated how macrophages, which play an important role in the innate immune system, in fact control the induction of adaptive immunity. This finding was significant enough to change the very assumptions upon which immunology as a field is based.


Volume 2: Susumu Kitagawa "Pioneering Studies on New Porous Metal Complexes—Porous Coordination Polymers"

“Porous materials” are solid matter with tiny spaces (pores). In particular, porous materials with molecular size spaces are indispensable in our daily lives and have attracted much attention as a cutting-edge research area in nanoscience technology.
A representative porous material is activated carbon.Prof. Kitagawa successfully synthesized porous materials using porous coordination polymers.
These advances in porous coordination polymers have raised expectations; it is envisioned that these polymers may be utilized in various applications, including to selectively store, release, separate, and transport molecules and ions and in the nanosynthesis of containers, catalysts, and sensors.


Volume 1: Isamu Akasaki "Establishing the Basic Technology for Blue Light-Emitting Diodes using Gallium Nitride"

Light-emitting diodes (LEDs) are lauded as the light source of the future, a fourth generation after gas lamps, incandescent lamps, and fluorescent lamps. LEDs were adapted for use in displays soon after development, but the development of the blue LED—essential for displays—was not successful for a long time. Many researchers gave up the search for the elusive blue LED, but one man, Dr. Isamu Akasaki, was unmoving in his determination to find the answer, which he did, in 1989, with his world-changing blue LED.