Abstract:
:Positive lower bounds for pseudo-differential operators with nonnegative symbols are derived; the bounds in particular yield subelliptic estimates for operators arising as sums of squares of vector fields.
journal_name
Proc Natl Acad Sci U S Aauthors
Fefferman C,Phong DHdoi
10.1073/pnas.76.12.6055subject
Has Abstractpub_date
1979-12-01 00:00:00pages
6055-6issue
12eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::A census of the biomass on Earth is key for understanding the structure and dynamics of the biosphere. However, a global, quantitative view of how the biomass of different taxa compare with one another is still lacking. Here, we assemble the overall biomass composition of the biosphere, establishing a census of the ≈5...
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.1711842115
更新日期:2018-06-19 00:00:00
abstract::Unconventional myosin 15 is a molecular motor expressed in inner ear hair cells that transports protein cargos within developing mechanosensory stereocilia. Mutations of myosin 15 cause profound hearing loss in humans and mice; however, the properties of this motor and its regulation within the stereocilia organelle a...
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.1409459111
更新日期:2014-08-26 00:00:00
abstract::Grain growth under shear annealing is crucial for controlling the properties of polycrystalline materials. However, their microscopic kinetics are not well understood because individual atomic trajectories are difficult to track. Here, we study grain growth with single-particle kinetics in colloidal polycrystals using...
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:2020-09-29 00:00:00
abstract::Using defined oligomers of IgE, our group previously studied the quantitative relationship between the aggregation of the high affinity receptors for IgE (Fc epsilonRI) and the earliest signals initiated by such aggregation: the phosphorylation of tyrosines on the receptor. Notably, at certain doses of the oligomers s...
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.94.4.1372
更新日期:1997-02-18 00:00:00
abstract::Amnesia produced by protein synthesis inhibitors such as anisomycin provides major support for the prevalent view that the formation of long-lasting memories requires de novo protein synthesis. However, inhibition of protein synthesis might disrupt other neural functions to interfere with memory formation. Intraamygda...
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.0705195104
更新日期:2007-07-24 00:00:00
abstract::Selection is usually considered to be the dominant force controlling viral variation; the large population sizes suggest that deterministic population genetic models are appropriate. To investigate their validity for HIV, samples of env gene sequences were tested for departure from neutrality because of mutation-selec...
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.94.5.1862
更新日期:1997-03-04 00:00:00
abstract::The restriction endonuclease, HindIII, gives rise to three fragments in each of the three mitochondrial DNAs isolated from the established mammalian cell lines LA9 (mouse), HeLa (human), and BSC-1 (African green monkey). The restriction endonuclease, EcoRI, gives rise to three fragments in mitochondrial DNA from HeLa ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1974-11-01 00:00:00
abstract::The poison frogs (family Dendrobatidae) are terrestrial anuran amphibians displaying a wide range of coloration and toxicity. These frogs generally have been considered to be aposematic, but relatively little research has been carried out to test the predictions of this hypothesis. Here we use a comparative approach t...
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.101134898
更新日期:2001-05-22 00:00:00
abstract::Structural symmetry is a hallmark of homomeric ion channels. Nonobligatory regulatory proteins can also critically define the precise functional role of such channels. For instance, the pore-forming subunit of the large conductance voltage and calcium-activated potassium (BK, Slo1, or KCa1.1) channels encoded by a sin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2018-10-02 00:00:00
abstract::Variation between North Korean and Latin American isolates in the circumsporozoite (CS) protein encoding gene of the human malaria parasite Plasmodium vivax was studied. Polymorphic positions are confined to the central tandemly repeated sequences. Nucleotide substitutions in the tandem repeats produce variants; these...
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.85.21.8102
更新日期:1988-11-01 00:00:00
abstract::Mouse serosal mast cells (SMCs) and Kirsten sarcoma virus-immortalized mast cells store large amounts of mast cell carboxypeptidase A and serine proteases in their secretory granules. Secretory granule proteins from 2.6 x 10(6) purified SMCs were separated by NaDodSO4/PAGE, trans-blotted to poly(vinylidine difluoride)...
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.87.8.3230
更新日期:1990-04-01 00:00:00
abstract::Transport of L-glutamine and of the chloroketone glutamine analog L-2-amino-4-oxo-5-chloropentanoate into lymphoid cells is mediated by the same system. Arginine and a number of other amino acids (e.g., glutamate, aspartate, and lysine) are transported to a much lesser extent by this system. However, after uptake of t...
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.76.10.4932
更新日期:1979-10-01 00:00:00
abstract::Signal peptides of membrane proteins are cleaved by endoplasmic reticulum-resident signal peptidase, and thus, are not present on mature membrane proteins. Here, we report that, contrary to the paradigm, the signal peptide of ruminant CD18, the beta-subunit of beta(2)-integrins, is not cleaved. Intriguingly, the intac...
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.0906775106
更新日期:2009-09-08 00:00:00
abstract::Most homeobox genes belonging to the Hox family are sequentially activated in embryonal carcinoma cells upon treatment with retinoic acid. Genes located at the 3' end of each one of the four Hox clusters are activated first, whereas upstream Hox genes are activated progressively later. This activation has been extensi...
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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abstract::The 4D organization of the interphase nucleus, or the 4D Nucleome (4DN), reflects a dynamical interaction between 3D genome structure and function and its relationship to phenotype. We present initial analyses of the human 4DN, capturing genome-wide structure using chromosome conformation capture and 3D imaging, and f...
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.1505822112
更新日期:2015-06-30 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.83.6.1827
更新日期:1986-03-01 00:00:00
abstract::The structure of the Rous sarcoma virus envelope glycoprotein complex was studied by sedimentation gradient centrifugation analyses of detergent-solubilized wild-type and mutant envelope (env) gene products. These studies show that the envelope glycoprotein forms an oligomer during biosynthesis, which is most likely a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::The [PSI+] prion is a self-propagating amyloid of the translation termination factor, Sup35p, of Saccharomyces cerevisiae. The N-terminal 253 residues (NM) of this 685-residue protein normally function in regulating mRNA turnover but spontaneously form infectious amyloid in vitro. We converted the three Ile residues i...
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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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abstract::To find the native conformation (fold), proteins sample a subspace that is typically hundreds of orders of magnitude smaller than their full conformational space. Whether such fast folding is intrinsic or the result of natural selection, and what is the longest foldable protein, are open questions. Here, we derive the...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-06-19 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-10-07 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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更新日期:2011-07-12 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:1982-11-01 00:00:00
abstract::Cytolytic pore-forming toxins are important for the virulence of many disease-causing bacteria. How target cells molecularly respond to these toxins and whether or not they can mount a defense are poorly understood. By using microarrays, we demonstrate that the nematode Caenorhabditis elegans responds robustly to Cry5...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2004-07-27 00:00:00
abstract::The liver plays a key role in the regulation of circulating levels of low density lipoproteins (LDL) because it is both the site for the production of and the major organ for the degradation of this class of lipoproteins. In this study, the effects of feeding polyunsaturated or saturated triacylglycerols on receptor-d...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1985-07-01 00:00:00