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The dependence of the critical current density j_c on the ferromagnetic interlayer thickness d_F was determined for Nb/Al_2O_3/Cu/Ni/Nb Josephson tunnel junctions with ferromagnetic \Ni interlayer from very thin film thicknesses (\sim 1 nm) upwards and classified into F-layer thickness regimes showing a dead magnetic layer, exchange, exchange + anisotropy and total suppression of j_c. The Josephson coupling changes from 0 to pi as function of d_F, and -very close to the crossover thickness- as function of temperature. The strong suppression of the supercurrent in comparison to non-magnetic \Nb/Al_2O_3/Cu/Nb junctions indicated that the insertion of a F-layer leads to additional interface scattering. The transport inside the dead magnetic layer was in dirty limit. For the magnetically active regime fitting with both the clean and the dirty limit theory were carried out, indicating dirty limit condition, too. The results were discussed in the framework of literature, Comment: 8 pages, 5 pictures v2: major conceptual changes

The mean intensity of Cerenkov emission from the products of K(40) decay and bioluminescence was measured at depths to 5 km. The intensity of ocean light background is found to depend upon depth and at the 5 km level is equal on averaged to 300 + or - 60 quanta/sq cms into spatial angle of 2 pi sterradian in transparency window. The amplitudes, duration and number of BL flashes were measured at various depths. The intensive flashes due to BL are shown to be observed rather seldom at depths over 4 km.