Abstract:
:Diatoms are usually the major component of the algal flora in many streams, although green and blue-green algae may be present. These experiments were designed to determine if high temperature or a shift in the chemical composition of the water might bring about a dominance of blue-green algae and/or green algae rather than a dominance of diatoms in the algal flora.The results of these experiments indicate that an average temperature of 34 degrees to 38 degrees C results in a shift of dominance in the algal flora from diatoms to blue-green algae. Furthermore, a blue-green and green algal flora of species typically found in organically polluted water in favored if the manganese content is a few parts per billion. If the manganese content averaged 0.02-0.043 mg/liter in the natural stream to 0.04-0.28 mg/liter in the recycled water experiment, a diatom flora remained dominant.
journal_name
Proc Natl Acad Sci U S Aauthors
Patrick R,Crum B,Coles Jdoi
10.1073/pnas.64.2.472subject
Has Abstractpub_date
1969-10-01 00:00:00pages
472-8issue
2eissn
0027-8424issn
1091-6490journal_volume
64pub_type
杂志文章abstract::Hypermutation in immunoglobulin genes produces a high frequency of substitutions of all four bases, which are likely generated by low-fidelity DNA polymerases. Indeed, humans deficient for DNA polymerase (pol) eta have decreased substitutions of A.T base pairs in variable and switch regions. To study the role of pol e...
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.0501852102
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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.88.21.9438
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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.93.17.9270
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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.88.11.4796
更新日期:1991-06-01 00:00:00
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更新日期:1999-03-02 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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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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