coils were wound by a pair of parallel wires, outer coils 42 turns and inner coils 37 turns
Both sham and exposure coil systems were placed in the same incubator. A µ-metal foil was placed between the two systems resulting in 30% reduction of the magnetic field.
Four coaxial coils placed horizontally and thus parallel with respect to the surface of the culture well plates. The diameter of the external coils (top and bottom) was 18 cm, while that of the internal ones was 20 cm. The geometry of the coil system was calculated to optimize the extension of the magnetic field uniformity. the distances between the external and internal coils from the center of the symmetry were 9 and 3 cm, respectively. According to these conditions the uniformity was better than 2% within a cylindrical region of ca. 11 cm (along the coil axis) x 9 cm, thus allowing simultaneous exposure of 6 culture well plates.
A sham exposure was conducted.
Sham field conditions (5 µT) were achieved by configuring the coils in counter wound arrangement to cancel each others magnetic field.