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71.
Recent decline in the global land evapotranspiration trend due to limited moisture supply 总被引:31,自引:0,他引:31
Jung M Reichstein M Ciais P Seneviratne SI Sheffield J Goulden ML Bonan G Cescatti A Chen J de Jeu R Dolman AJ Eugster W Gerten D Gianelle D Gobron N Heinke J Kimball J Law BE Montagnani L Mu Q Mueller B Oleson K Papale D Richardson AD Roupsard O Running S Tomelleri E Viovy N Weber U Williams C Wood E Zaehle S Zhang K 《Nature》2010,467(7318):951-954
More than half of the solar energy absorbed by land surfaces is currently used to evaporate water. Climate change is expected to intensify the hydrological cycle and to alter evapotranspiration, with implications for ecosystem services and feedback to regional and global climate. Evapotranspiration changes may already be under way, but direct observational constraints are lacking at the global scale. Until such evidence is available, changes in the water cycle on land?a key diagnostic criterion of the effects of climate change and variability?remain uncertain. Here we provide a data-driven estimate of global land evapotranspiration from 1982 to 2008, compiled using a global monitoring network, meteorological and remote-sensing observations, and a machine-learning algorithm. In addition, we have assessed evapotranspiration variations over the same time period using an ensemble of process-based land-surface models. Our results suggest that global annual evapotranspiration increased on average by 7.1?±?1.0?millimetres per year per decade from 1982 to 1997. After that, coincident with the last major El Ni?o event in 1998, the global evapotranspiration increase seems to have ceased until 2008. This change was driven primarily by moisture limitation in the Southern Hemisphere, particularly Africa and Australia. In these regions, microwave satellite observations indicate that soil moisture decreased from 1998 to 2008. Hence, increasing soil-moisture limitations on evapotranspiration largely explain the recent decline of the global land-evapotranspiration trend. Whether the changing behaviour of evapotranspiration is representative of natural climate variability or reflects a more permanent reorganization of the land water cycle is a key question for earth system science. 相似文献
72.
Markus Thamm Sabine Balfanz Ricarda Scheiner Arnd Baumann Wolfgang Blenau 《Cellular and molecular life sciences : CMLS》2010,67(14):2467-2479
Serotonin plays a key role in modulating various physiological and behavioral processes in both protostomes and deuterostomes.
The vast majority of serotonin receptors belong to the superfamily of G-protein-coupled receptors. We report the cloning of
a cDNA from the honeybee (Am5-ht1A) sharing high similarity with members of the 5-HT1 receptor class. Activation of Am5-HT1A by serotonin inhibited the production of cAMP in a dose-dependent manner (EC50 = 16.9 nM). Am5-HT1A was highly expressed in brain regions known to be involved in visual information processing. Using in vivo pharmacology,
we could demonstrate that Am5-HT1A receptor ligands had a strong impact on the phototactic behavior of individual bees. The data presented here mark the first
comprehensive study—from gene to behavior—of a 5-HT1A receptor in the honeybee, paving the way for the eventual elucidation of additional roles of this receptor subtype in the
physiology and behavior of this social insect. 相似文献
73.
Chiow KH Tan Y Chua RY Huang D Ng ML Torta F Wenk MR Wong SH 《Cellular and molecular life sciences : CMLS》2012,69(9):1505-1521
Since being introduced globally as aspirin in 1899, acetylsalicylic acid has been widely used as an analgesic, anti-inflammation,
anti-pyretic, and anti-thrombotic drug for years. Aspirin had been reported to down-regulate surface expression of CD40, CD80,
CD86, and MHCII in myeloid dendritic cells (DC), which played essential roles in regulating the immune system. We hypothesized
that the down-regulation of these surface membrane proteins is partly due to the ability of aspirin in regulating trafficking/sorting
of endocytosed surface membrane proteins. By using an established epidermoid carcinoma cell line (A-431), which overexpresses
the epidermal growth factor receptor (EGFR) and transferrin receptor (TfnR), we show that aspirin (1) reduces cell surface
expression of EGFR and (2) accumulates endocytosed-EGFR and -TfnR in the early/sorting endosome (ESE). Further elucidation
of the mechanism suggests that aspirin enhances recruitment of SNX3 and SNX5 to membranes and consistently, both SNX3 and
SNX5 play essential roles in the aspirin-mediated accumulation of endocytosed-TfnR at the ESE. This study sheds light on how
aspirin may down-regulate surface expression of EGFR by inhibiting/delaying the exit of endocytosed-EGFR from the ESE and
recycling of endocytosed-EGFR back to the cell surface. 相似文献
74.
Genome-wide association study identifies multiple loci influencing human serum metabolite levels 总被引:1,自引:0,他引:1
Kettunen J Tukiainen T Sarin AP Ortega-Alonso A Tikkanen E Lyytikäinen LP Kangas AJ Soininen P Würtz P Silander K Dick DM Rose RJ Savolainen MJ Viikari J Kähönen M Lehtimäki T Pietiläinen KH Inouye M McCarthy MI Jula A Eriksson J Raitakari OT Salomaa V Kaprio J Järvelin MR Peltonen L Perola M Freimer NB Ala-Korpela M Palotie A Ripatti S 《Nature genetics》2012,44(3):269-276
Nuclear magnetic resonance assays allow for measurement of a wide range of metabolic phenotypes. We report here the results of a GWAS on 8,330 Finnish individuals genotyped and imputed at 7.7 million SNPs for a range of 216 serum metabolic phenotypes assessed by NMR of serum samples. We identified significant associations (P < 2.31 × 10(-10)) at 31 loci, including 11 for which there have not been previous reports of associations to a metabolic trait or disorder. Analyses of Finnish twin pairs suggested that the metabolic measures reported here show higher heritability than comparable conventional metabolic phenotypes. In accordance with our expectations, SNPs at the 31 loci associated with individual metabolites account for a greater proportion of the genetic component of trait variance (up to 40%) than is typically observed for conventional serum metabolic phenotypes. The identification of such associations may provide substantial insight into cardiometabolic disorders. 相似文献
75.
Bass AJ Lawrence MS Brace LE Ramos AH Drier Y Cibulskis K Sougnez C Voet D Saksena G Sivachenko A Jing R Parkin M Pugh T Verhaak RG Stransky N Boutin AT Barretina J Solit DB Vakiani E Shao W Mishina Y Warmuth M Jimenez J Chiang DY Signoretti S Kaelin WG Spardy N Hahn WC Hoshida Y Ogino S Depinho RA Chin L Garraway LA Fuchs CS Baselga J Tabernero J Gabriel S Lander ES Getz G Meyerson M 《Nature genetics》2011,43(10):964-968
Prior studies have identified recurrent oncogenic mutations in colorectal adenocarcinoma and have surveyed exons of protein-coding genes for mutations in 11 affected individuals. Here we report whole-genome sequencing from nine individuals with colorectal cancer, including primary colorectal tumors and matched adjacent non-tumor tissues, at an average of 30.7× and 31.9× coverage, respectively. We identify an average of 75 somatic rearrangements per tumor, including complex networks of translocations between pairs of chromosomes. Eleven rearrangements encode predicted in-frame fusion proteins, including a fusion of VTI1A and TCF7L2 found in 3 out of 97 colorectal cancers. Although TCF7L2 encodes TCF4, which cooperates with β-catenin in colorectal carcinogenesis, the fusion lacks the TCF4 β-catenin-binding domain. We found a colorectal carcinoma cell line harboring the fusion gene to be dependent on VTI1A-TCF7L2 for anchorage-independent growth using RNA interference-mediated knockdown. This study shows previously unidentified levels of genomic rearrangements in colorectal carcinoma that can lead to essential gene fusions and other oncogenic events. 相似文献
76.
Shi Y Li Z Xu Q Wang T Li T Shen J Zhang F Chen J Zhou G Ji W Li B Xu Y Liu D Wang P Yang P Liu B Sun W Wan C Qin S He G Steinberg S Cichon S Werge T Sigurdsson E Tosato S Palotie A Nöthen MM Rietschel M Ophoff RA Collier DA Rujescu D Clair DS Stefansson H Stefansson K Ji J Wang Q Li W Zheng L Zhang H Feng G He L 《Nature genetics》2011,43(12):1224-1227
Schizophrenia is a severe mental disorder affecting ~1% of the world population, with heritability of up to 80%. To identify new common genetic risk factors, we performed a genome-wide association study (GWAS) in the Han Chinese population. The discovery sample set consisted of 3,750 individuals with schizophrenia and 6,468 healthy controls (1,578 cases and 1,592 controls from northern Han Chinese, 1,238 cases and 2,856 controls from central Han Chinese, and 934 cases and 2,020 controls from the southern Han Chinese). We further analyzed the strongest association signals in an additional independent cohort of 4,383 cases and 4,539 controls from the Han Chinese population. Meta-analysis identified common SNPs that associated with schizophrenia with genome-wide significance on 8p12 (rs16887244, P = 1.27 × 10(-10)) and 1q24.2 (rs10489202, P = 9.50 × 10(-9)). Our findings provide new insights into the pathogenesis of schizophrenia. 相似文献
77.
78.
Combinatorial microRNA target predictions 总被引:59,自引:0,他引:59
Krek A Grün D Poy MN Wolf R Rosenberg L Epstein EJ MacMenamin P da Piedade I Gunsalus KC Stoffel M Rajewsky N 《Nature genetics》2005,37(5):495-500
79.
Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms. 总被引:12,自引:0,他引:12
Markus Greiner Olaf Mandel Tilman Esslinger Theodor W H?nsch Immanuel Bloch 《Nature》2002,415(6867):39-44
For a system at a temperature of absolute zero, all thermal fluctuations are frozen out, while quantum fluctuations prevail. These microscopic quantum fluctuations can induce a macroscopic phase transition in the ground state of a many-body system when the relative strength of two competing energy terms is varied across a critical value. Here we observe such a quantum phase transition in a Bose-Einstein condensate with repulsive interactions, held in a three-dimensional optical lattice potential. As the potential depth of the lattice is increased, a transition is observed from a superfluid to a Mott insulator phase. In the superfluid phase, each atom is spread out over the entire lattice, with long-range phase coherence. But in the insulating phase, exact numbers of atoms are localized at individual lattice sites, with no phase coherence across the lattice; this phase is characterized by a gap in the excitation spectrum. We can induce reversible changes between the two ground states of the system. 相似文献
80.