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131.
Copper porphyrins in deep-sea sediments: a possible indicator of oxidized terrestrial organic matter
Copper porphyrins have been isolated from deep-sea sediments collected during six legs of the Deep Sea Drilling Project-International Program of Ocean Drilling. These pigments are present in depositional areas receiving high inputs of terrestrially derived oxidized organic matter. Such areas include the Black Sea, the Bay of Biscay, the Blake-Bahama Basin, and slumped Miocene deposits off Cape Bojador on the west coast of Africa. 相似文献
132.
The reproductive organs of some plants self-heat, release scent, and attract pollinators. The relations among these processes are not well understood, especially in the more ancient, nonflowering gymnosperm lineages. We describe the influence of plant volatiles in an obligate pollination mutualism between an Australian Macrozamia cycad (a gymnosperm with male and female individuals) and its specialist thrips pollinator, Cycadothrips chadwicki. Pollen-laden thrips leave male cycad cones en masse during the daily thermogenic phase, when cone temperatures and volatile emissions increase dramatically and thrips are repelled. As thermogenesis declines, total volatile emissions diminish and cones attract thrips, resulting in pollination of female cones. Behavioral and electrophysiological tests on thrips reveal that variations in b-myrcene and ocimene emissions by male and female cones are sufficient to explain the observed sequential thrips' repellence (push) and attraction (pull). These dynamic interactions represent complex adaptations that enhance the likelihood of pollination and may reflect an intermediate state in the evolution of biotic pollination. 相似文献
133.
Miller C 《Science (New York, N.Y.)》2007,315(5811):459
134.
Microcolonial structures have been harvested from desert rock samples for cultivation and ultrastructural examination. The results indicate that these microcolonial structures are fungi previously unrecognized as inhabitants of desert rocks. 相似文献
135.
Palmer JK 《Science (New York, N.Y.)》1957,126(3272):504-505
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Keeling PJ Archibald JM Fast NM Palmer JD 《Science (New York, N.Y.)》2004,306(5705):2191; author reply 2191
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Bartke A Wright JC Mattison JA Ingram DK Miller RA Roth GS 《Science (New York, N.Y.)》2002,296(5576):2141-2; author reply 2141-2