Abstract:
:The 2012-2015 drought has left California with severely reduced snowpack, soil moisture, ground water, and reservoir stocks, but the impact of this estimated millennial-scale event on forest health is unknown. We used airborne laser-guided spectroscopy and satellite-based models to assess losses in canopy water content of California's forests between 2011 and 2015. Approximately 10.6 million ha of forest containing up to 888 million large trees experienced measurable loss in canopy water content during this drought period. Severe canopy water losses of greater than 30% occurred over 1 million ha, affecting up to 58 million large trees. Our measurements exclude forests affected by fire between 2011 and 2015. If drought conditions continue or reoccur, even with temporary reprieves such as El Niño, we predict substantial future forest change.
journal_name
Proc Natl Acad Sci U S Aauthors
Asner GP,Brodrick PG,Anderson CB,Vaughn N,Knapp DE,Martin REdoi
10.1073/pnas.1523397113subject
Has Abstractpub_date
2016-01-12 00:00:00pages
E249-55issue
2eissn
0027-8424issn
1091-6490pii
1523397113journal_volume
113pub_type
杂志文章abstract::The precipitation and assembly of calcium carbonate skeletons by stony corals is a precisely controlled process regulated by the secretion of an ECM. Recently, it has been reported that the proteome of the skeletal organic matrix (SOM) contains a group of coral acid-rich proteins as well as an assemblage of adhesion 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.1408621111
更新日期:2014-09-02 00:00:00
abstract::Plant metabolites are crucial for both plant life and human nutrition. Despite recent advance in metabolomics, the genetic control of plant metabolome remains largely unknown. Here, we performed a genetic analysis of the rice metabolome that provided over 2,800 highly resolved metabolic quantitative trait loci for 900...
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.1319681110
更新日期:2013-12-10 00:00:00
abstract::Tephritid fruit flies belonging to the Rhagoletis pomonella sibling species complex are controversial because they have been proposed to diverge in sympatry (in the absence of geographic isolation) by shifting and adapting to new host plants. Here, we report evidence suggesting a surprising source of genetic variation...
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.1730757100
更新日期:2003-09-02 00:00:00
abstract::We quantitatively analyzed, using laser scanning confocal microscopy, the three-dimensional structure of individual senile plaques in Alzheimer disease. We carried out the quantitative analysis using statistical methods to gain insights about the processes that govern Abeta peptide deposition. Our results show that pl...
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.94.14.7612
更新日期:1997-07-08 00:00:00
abstract::Many Drosophila non-long terminal repeat (LTR) retrotransposons actively transpose into internal, gene-rich regions of chromosomes but do not transpose onto chromosome ends. HeT-A and TART are remarkable exceptions; they form telomeres of Drosophila by repeated transpositions onto the ends of chromosomes and never tra...
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.032071999
更新日期:2002-03-19 00:00:00
abstract::Several polypeptides contained in the coat and the core of adenovirus type 2 particles have been identified as virus gene products. They are synthesized in vitro by a cell-free protein-making system programmed by adenovirus type 2 messenger RNA that has been hybridized with and eluted from virus DNA. Fractionation by ...
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.71.9.3385
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abstract::Many insects are dependent on bacterial symbionts that provide essential nutrients (ex. aphid-Buchnera and tsetse-Wiglesworthia associations), wherein the symbionts are harbored in specific cells called bacteriocytes that constitute a symbiotic organ bacteriome. Facultative and parasitic bacterial symbionts like Wolba...
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.0911476107
更新日期:2010-01-12 00:00:00
abstract::Glucocorticoids (GCs) are potent anti-inflammatory agents that block cytokine production. We investigated whether GCs also block cytokine signaling via the Janus kinase (Jak)-signal transducer and activator of transcription (STAT) pathway. Dexamethasone inhibited IL-2-induced DNA binding, tyrosine phosphorylation, and...
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.160099797
更新日期:2000-08-15 00:00:00
abstract::The effect of reflex splanchnic nerve stimulation on proenkephalin A biosynthesis was investigated in the rat adrenal medulla. Tissue levels of native [Met5]enkephalin-like immunoreactivity (IR) (measured by direct RIA of tissue extracts), cryptic [Met5]enkephalin-like IR (calculated as the increase in [Met5]enkephali...
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.83.23.9245
更新日期:1986-12-01 00:00:00
abstract::Targeting the endothelial cell cycle as an antiangiogenic strategy has been difficult given the ubiquitous expression of critical cell cycle regulators. Here, we show that the antiangiogenic drug TNP-470 displays striking cell-type specificity insofar as it induces the expression of p21(CIP/WAF), a cyclin-dependent ki...
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.97.23.12782
更新日期:2000-11-07 00:00:00
abstract::A mutant (ML 308-22) was isolated from Escherichia coli ML 308, which had lost the normal capacity to accumulate lactose analogs despite an increase in the membrane carrier activity. The exit of thiomethylgalactoside was much faster than normal, accounting for the inability of the cell to maintain high intracellular c...
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.65.1.63
更新日期:1970-01-01 00:00:00
abstract::Aggregation of p53 is initiated by first-order processes that generate an aggregation-prone state with parallel pathways of major or partial unfolding. Here, we elaborate the mechanism and explore its consequences, beginning with the core domain and extending to the full-length p53 mutant Y220C. Production of large li...
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.1211557109
更新日期:2012-08-21 00:00:00
abstract::Paleoanthropologists and vertebrate paleontologists have for decades debated the etiology of tooth wear and its implications for understanding the diets of human ancestors and other extinct mammals. The debate has recently taken a twist, calling into question the efficacy of dental microwear to reveal diet. Some argue...
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.1509491112
更新日期:2015-08-25 00:00:00
abstract::Application of hydrostatic pressure shifts protein conformational equilibria in a direction to reduce the volume of the system. A current view is that the volume reduction is dominated by elimination of voids or cavities in the protein interior via cavity hydration, although an alternative mechanism wherein cavities 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.1506505112
更新日期:2015-05-12 00:00:00
abstract::The tau and gamma subunits of DNA polymerase III holoenzyme are both products of the dnaX gene. Since tau and gamma are required as stoichiometric components of the replicative complex, a mechanism must exist for the cell to coordinate their synthesis and ensure that both subunits are present in an adequate quantity 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.87.10.3713
更新日期:1990-05-01 00:00:00
abstract::We derive more than 80 embeddings of 2D hyperbolic honeycombs in Euclidean 3 space, forming 3-periodic infinite polyhedra with cubic symmetry. All embeddings are "minimally frustrated," formed by removing just enough isometries of the (regular, but unphysical) 2D hyperbolic honeycombs [Formula: see text], [Formula: se...
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.1720307115
更新日期:2018-07-03 00:00:00
abstract::Many "workers" in north temperate colonies of the eusocial paper wasp Polistes fuscatus disappear within a few days of eclosion. We provide evidence that these females are pursuing an alternative reproductive strategy, i.e., dispersing to overwinter and become nest foundresses the following spring, instead of helping ...
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.95.23.13737
更新日期:1998-11-10 00:00:00
abstract::The corticotropin-releasing factor (CRF) ligand family has diverse effects on the CNS, including the modulation of the stress response. The ligands' effects are mediated by binding to CRF G protein-coupled receptors. We have determined the 3D NMR structure of the N-terminal extracellular domain (ECD1) of the mouse CRF...
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.0404702101
更新日期:2004-08-31 00:00:00
abstract::Cyclic AMP (cAMP) and calcium are ubiquitous, interdependent second messengers that regulate a wide range of cellular processes. During development of neuronal networks they are critical for the first step of circuit formation, transducing signals required for axon pathfinding. Surprisingly, the spatial and temporal c...
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.1100247108
更新日期:2011-08-16 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.2034995100
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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.211257298
更新日期:2001-10-09 00:00:00
abstract::Isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) represent the two central intermediates in the biosynthesis of isoprenoids. The recently discovered deoxyxylulose 5-phosphate pathway generates a mixture of IPP and DMAPP in its final step by reductive dehydroxylation of 1-hydroxy-2-methyl-2-butenyl 4...
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.0913045107
更新日期:2010-01-19 00:00:00
abstract::Escherichia coli is a model laboratory bacterium, a species that is widely distributed in the environment, as well as a mutualist and pathogen in its human hosts. As such, E. coli represents an attractive organism to study how environment impacts microbial genome structure and function. Uropathogenic E. coli (UPEC) mu...
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.0600938103
更新日期:2006-04-11 00:00:00
abstract::In facultative photoperiodic flowering plants, noninductive photoperiods result in a delay in flowering, but such plants eventually flower, illustrating plasticity in an important developmental transition, flowering. The model plant, Arabidopsis, has a facultative photoperiod response. Although the inductive flowering...
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.1010834107
更新日期:2010-09-28 00:00:00
abstract::Systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes parkinsonism in humans and subhuman primates, but not in rats and many other laboratory animals; mice are intermediate in their susceptibility. Since MPTP causes selective dopaminergic neurotoxicity when infused directly into rat sub...
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.84.10.3521
更新日期:1987-05-01 00:00:00
abstract::Herpesvirus extracted from a naturally occurring frog renal carcinoma (Lucké tumor) induced virus-free Lucké tumors in developing frogs. Herpesvirus recovered from an induced tumor after incubation at low temperature of tumor fragments cultured in vitro was oncogenic when injected into developing frog embryos. With th...
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.71.3.830
更新日期:1974-03-01 00:00:00
abstract::Telomerase activity was identified in extracts from several different mouse cell lines. Addition of telomeric TTAGGG repeats was specific to telomeric oligonucleotide primers and sensitive to pretreatment with RNase A. In contrast to the hundreds of repeats synthesized by the human and Tetrahymena telomerase enzymes i...
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.90.4.1493
更新日期:1993-02-15 00:00:00
abstract::Asexual freshwater planarians reproduce by tearing themselves into two pieces by a process called binary fission. The resulting head and tail pieces regenerate within about a week, forming two new worms. Understanding this process of ripping oneself into two parts poses a challenging biomechanical problem. Because pla...
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.1700762114
更新日期:2017-10-10 00:00:00
abstract::Previously we uncovered a critical role for norepinephrine and beta(1)-adrenergic signaling in hippocampus-dependent memory retrieval. Because the beta(1) receptor couples to G(s), we examine here whether cAMP is also required for contextual memory retrieval. Using pharmacologic and genetic approaches to manipulate cA...
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.0804172105
更新日期:2008-08-19 00:00:00
abstract::We describe a new computer program, trilogy, for the automated discovery of sequence-structure patterns in proteins. trilogy implements a pattern discovery algorithm that begins with an exhaustive analysis of flexible three-residue patterns; a subset of these patterns are selected as seeds for an extension process in ...
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.112221999
更新日期:2002-06-25 00:00:00