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Abstract--From 2001 to 2006, 71 pop-up satellite archival tags (PSATs) were deployed on five species of pelagic shark (blue shark [Prionace glauca]; shortfin mako [Isurus oxyrinchus]; silky shark [Carcharhinus falciformis]; [...]

The pole-and-line fishery for skipjack tuna, Katsuwonus pelamis, was the largest commercial fishery in Hawaii until its decline in the 1970's and 1980's. The development and decline of the fishery were strongly affected by fish availability and marketing. A sustained drop in the availability of large fish in the mid-1970's appears to have been due in part to a sustained environmental change. Availability of largefish subsequently increased, but the fishery continued its decline owing to low profitability and lack of markets. The tuna cannery in Honolulu that fostered the fishery's expansion in the 1930's closed in 1984. Unless efforts to increase the market for skipjack tuna become effective, landings will probably remain at current levels of about 1,000 metric tons per year. The existing pole-and-line fleet may continue to decline with age, and the local market may eventually be supplied by other fishing methods (e.g., trolling), by new vessels, or by imports., Introduction Historically, the pole-and-line, live-bait fishery for skipjack tuna, Katsuwonus pelamis, was the largest commercial fishery in Hawaii. Annual pole-and-line landings of skipjack tuna exceeded 2,500 metric tons (t) or [...]

The isovalent substitution of Ca[sup 2+] for Sr[sup 2+] substitution in the recently discovered misfit cobaltite [Pb[sub 0.7]Co[sub 0.3]Sr[sub 2]O[sub 3]] [CoO[sub 2]] [sub 1.79] has been investigated for its very attractive thermopower properties. Starting from the pure Sr cobaltite with a thermopower S value at 300 K in the range from 100 to 130 µV K[sup -1], it is found that the calcium substitution enhances the thermopower value up to + 165 µVK[sup -1] for the pure calcium phase, [Pb[sub 0.4]Co[sub 0.6]Ca[sub 2]O[sub 3] [CoO[sub 2][sub 1.61]. Since these thermoelectric materials are studied for the high T applications, it should be pointed out that this S improvement induced by chemical substitution is even more pronounced for T ... 300 K with S[sub 700] K = + 210 µV K[sup -1]. This beneficial effect is interpreted in the light of the clear modification in the geometry of CoO[sub 2] layers which could play a role on the cobalt electronic configurations. [ABSTRACT FROM AUTHOR]

Ca[sub 3-χ]Sr[sub χ]Co[sub 4]O[sub 9] (χ = 0,0.5,1.0) samples were prepared by solid state reaction. As expected from the radii of Sr[sup 2+] and Ca[sup 2+], the cell parameters increase with Sr content χ. Simultaneously, the resistivity and the carrier localization at low temperature are enhanced. The thermoelectric power is not sensitive to the Sr content. Furthermore, the ferromagnetism at low temperature becomes weaker with the increase of Sr content, which shows that antiferromagnetism and ferromagnetism compete in these cobaltites. Large Sr content enhances antiferromagnetic interactions, which can be related to the extending plateau of magnetoresistance ratio of ρ(H)/ρ(0) in the low magnetic field region. [ABSTRACT FROM AUTHOR]