Abstract:
:In a subtropical gyre, the convergent Ekman layer forces water downward into the geostrophic flow below. The properties and depth of the mixed layer vary considerably during the course of the year, but this variability does not penetrate into the geostrophic region. Evidently there is some process at work that selects only late winter water for actual net downward pumping. It is a process much like that performed by Maxwell's Demon. Arguing from a particular example in a North Atlantic region where Sverdrup dynamics is presumed to prevail, an elementary description is given as to how the Demon works and a sample set of profiles by season is computed. Present day mixed layer models involve a local vertical mixing process. Thermocline theories involve adiabatic flow from high latitudes. There is an intermediate depth range at which the two processes operate alternatively, according to season.
journal_name
Proc Natl Acad Sci U S Aauthors
Stommel Hdoi
10.1073/pnas.76.7.3051subject
Has Abstractpub_date
1979-07-01 00:00:00pages
3051-5issue
7eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::The spleen from a patient with adult Gaucher's disease was shown to be deficient in a beta-glucosidase (EC 3.2.1.21) isoenzyme that has optimal activity at pH 4.0-4.3, and is stimulated by 0.02% Triton X-100. A mixture of spleen homogenates from a control and from the patient contained beta-glucosidase activity equiva...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.68.11.2810
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abstract::Searches of ribosomal RNA sequences for compensatory base changes preserving Watson-Crick base pairing have led to detailed models of the conserved secondary structures of these RNAs. In principle, tertiary interactions can also be detected by searches for phylogenetically covariant bases. Within a highly conserved re...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.14.6308
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.78.11.7091
更新日期:1981-11-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.232058599
更新日期:2002-11-12 00:00:00
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更新日期:2005-03-29 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.82.23.8266
更新日期:1985-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.12.5572
更新日期:1995-06-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1004148107
更新日期:2010-06-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.2.870
更新日期:1980-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2010-12-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.17.6907
更新日期:1990-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.80.8.2201
更新日期:1983-04-01 00:00:00
abstract::The structure of respiratory cytochrome c551 of Pseudomonas aeruginosa, with 82 amino acids, has been solved by x-ray analysis and refined to a crystallographic R factor of 16.2%. It has the same basic folding pattern and hydrophobic heme environment as cytochromes c, c2, and c550, except for a large deletion at the b...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.75.6.2674
更新日期:1978-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
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更新日期:1996-11-26 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2004-11-16 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2007-12-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0408134101
更新日期:2004-12-21 00:00:00
abstract::Inhibition of eicosanoid formation in larvae of the tobacco hornworm Manduca sexta, using specific inhibitors of phospholipase A2, cyclooxygenase, and lipoxygenase, severely weakened the ability of larvae to clear the bacterium Serratia marscescens from their hemolymph. The reduced capability to remove bacteria is ass...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.3.1064
更新日期:1991-02-01 00:00:00
abstract::With the goal of developing techniques for DNA insertional mutagenesis in zebrafish, we established procedures for rapidly obtaining and injecting large numbers of fertilized eggs. Using either of two plasmid constructs, we injected uncut DNA into fertilized eggs at the one- or two-cell stage. Fish hatched from inject...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1991-09-15 00:00:00
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更新日期:2008-08-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1969-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2011-07-26 00:00:00
abstract::A glucose-responsive "closed-loop" insulin delivery system mimicking the function of pancreatic cells has tremendous potential to improve quality of life and health in diabetics. Here, we report a novel glucose-responsive insulin delivery device using a painless microneedle-array patch ("smart insulin patch") containi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2015-07-07 00:00:00