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Bioelectromagnetism

FIGURE 2.14 Demonstration of the Moses efect using a super-conducting magnet (From Ueno and Iwasaka)

be seen. Te water level at both ends of the chamber was raised (Ueno and Iwasaka, 1994a). Figure 2.14

shows the demonstration of the Moses efect with agarose gels which allow the formation of surface

changes in magnetic felds. Te phenomenon of Moses efect is closely in association with the Biblical

story. It describes that Moses, the most important prophet, divided the Red Sea into two parts when the

Israelites wandered through the wildness afer their Exodus from Egypt. Ueno received the d’Arsonval

Medal from the Bioelectromagnetics Society in 2010.

If a container of a paramagnetic liquid is placed in a strong magnet, a phenomenon occurs in which

the liquid rises in the center of the container. Tis phenomenon is called the inverse (reversed) Moses

efect. Tis inverse Moses efect was frst presented by Noriyuki Hirota from the University of Tokyo and

others in 1995 (Hirota et al., 1995). Tey showed the change of surface profle of aqueous solutions with

diferent magnetic susceptibility. In order to compare, they used distilled water and saturated copper

sulfate (CuSO4) aqueous solutions, the former has diamagnetic character with χ =−9.031 × 10⁻⁶ (SI) and

the latter solution is paramagnetic character with χ =+8.397 × 10⁻⁶ (SI). Under a 10 T superconducting

magnet, the changes in the surfaces of diamagnetic and paramagnetic liquids are due to diferences in

their respective magnetic susceptibilities. In the case of distilled water, the fall of the surface was shown

in the center of the magnet. On the other hand, the rise of the surface of saturated CuSO4 aqueous solu­

tion was obtained.

2.5.2.2 Magnetic Resonance Imaging

MRI was introduced as the most advanced diagnostic imaging technology in medicine in the early

1980s. MRI is based on the Nuclear Magnetic Resonance (NMR) of water molecules with the use of elec­

tromagnetic felds. Historically, NMR was frst described and measured in molecular beams by Isidor

Isaac Rabi (1898–1988), Nobel Laureate in 1944, Columbia University, with his associates Norman Foster

Ramsey (1915–2011), Nobel Laureate in 1989. In 1946, Edward Mills Purcell (1912–1997), an American

physicist at Harvard University, and Felix Bloch (1905–1983), a Swiss-American physicist at Stanford

University, invented the NMR. NMR is a physical observation method in which nuclei in a strong and