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Yttrium-excess Y x Ba2Cu3O y (1.00≤x≤1.25) superconductors have been fabricated by a combination process of ordinary solid-state reaction and partial melting. Sintering the yttrium-excess Y x Ba2Cu3O y results in extremely small grains, which in turn produce uniformly distributed fine Y2BaCuO5 during partial melting. Y2BaCuO5 acts as the nucleation site for peritectic reaction. The unreacted Y2BaCuO5 seems to act as a flux pinning center. Due to this flux pinning force, the yttrium-excess Y x Ba2Cu3O y superconductors have very high critical current densities of about 22,000 A/cm2 (at 77 K, 1 T).

The effective action of the radion in the Randall-Sundrum model is analysed. When one loop effects stabilize the radion field, the cosmological evolution can be derived from a simple Friedman equation. Fine tunings are still needed to obtain the observed mass hierarchy and an invisible radion. Since kinetic terms are important for determining the radion mass, the finite quantum corrections from massless conformally coupled fermions are analysed and found to vanish at one loop order.