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91.
92.
Engel E. Cayenne; Weltzin Jake F.; Norby Richard J.; Classen Aimee T. 《Journal of Plant Ecology》2009,2(1):1-11
Aims: The direct effects of atmospheric and climatic change factors—atmospheric[CO2], air temperature and changes in precipitation—canshape plant community composition and alter ecosystem function.It is essential to understand how these factors interact tomake better predictions about how ecosystems may respond tochange. We investigated the direct and interactive effects of[CO2], warming and altered soil moisture in open-top chambers(OTCs) enclosing a constructed old-field community to test howthese factors shape plant communities. Materials and methods: The experimental facility in Oak Ridge, TN, USA, made use of4-m diameter OTCs and rain shelters to manipulate [CO2] (ambient,ambient + 300 ppm), air temperature (ambient, ambient + 3.5°C)and soil moisture (wet, dry). The plant communities within thechambers comprised seven common old-field species, includinggrasses, forbs and legumes. We tracked foliar cover for eachspecies and calculated community richness, evenness and diversityfrom 2003 to 2005. Important findings: This work resulted in three main findings: (1) warming had species-specificeffects on foliar cover that varied through time and were alteredby soil moisture treatments; (2) [CO2] had little effect onindividual species or the community; (3) diversity, evennessand richness were influenced most by soil moisture, primarilyreflecting the response of one dominant species. We concludethat individualistic species responses to atmospheric and climaticchange can alter community composition and that plant populationsand communities should be considered as part of analyses ofterrestrial ecosystem response to climate change. However, predictionof plant community responses may be difficult given interactionsbetween factors and changes in response through time. 相似文献
93.
Aimee Rindoks 《Biotechnology journal》2009,4(4):456-457
The Youth Conference on European Life Science Careers News from academia: Women in Science Award for structural biologist 相似文献
94.
95.
Topp S Reynoso CM Seeliger JC Goldlust IS Desai SK Murat D Shen A Puri AW Komeili A Bertozzi CR Scott JR Gallivan JP 《Applied and environmental microbiology》2010,76(23):7881-7884
We developed a series of ligand-inducible riboswitches that control gene expression in diverse species of Gram-negative and Gram-positive bacteria, including human pathogens that have few or no previously reported inducible expression systems. We anticipate that these riboswitches will be useful tools for genetic studies in a wide range of bacteria. 相似文献
96.
97.
Labile soil carbon inputs mediate the soil microbial community composition and plant residue decomposition rates 总被引:2,自引:0,他引:2
Root carbon (C) inputs may regulate decomposition rates in soil, and in this study we ask: how do labile C inputs regulate decomposition of plant residues, and soil microbial communities? In a 14 d laboratory incubation, we added C compounds often found in root exudates in seven different concentrations (0, 0.7, 1.4, 3.6, 7.2, 14.4 and 21.7 mg C g(-1) soil) to soils amended with and without (13) C-labeled plant residue. We measured CO(2) respiration and shifts in relative fungal and bacterial rRNA gene copy numbers using quantitative polymerase chain reaction (qPCR). Increased labile C input enhanced total C respiration, but only addition of C at low concentrations (0.7 mg C g(-1)) stimulated plant residue decomposition (+2%). Intermediate concentrations (1.4, 3.6 mg C g(-1)) had no impact on plant residue decomposition, while greater concentrations of C (>7.2 mg C g(-1)) reduced decomposition (-50%). Concurrently, high exudate concentrations (>3.6 mg C g(-1)) increased fungal and bacterial gene copy numbers, whereas low exudate concentrations (<3.6 mg C g(-1)) increased metabolic activity rather than gene copy numbers. These results underscore that labile soil C inputs can regulate decomposition of more recalcitrant soil C by controlling the activity and relative abundance of fungi and bacteria. 相似文献
98.
Aimee L. Crombie Thomas M. Antrilli Brandon A. Campbell David L. Crandall Amedeo A. Failli Yanan He Jeffrey C. Kern William J. Moore Lisa M. Nogle Eugene J. Trybulski 《Bioorganic & medicinal chemistry letters》2010,20(12):3742-3745
A series of biaryl amides containing an azabicyclooctane amine headpiece were synthesized and evaluated as mixed arginine vasopressin (AVP) receptor antagonists. Several analogues, including 8g, 12g, 13d, and 13g, were shown to have excellent V1a- and good V2-receptor binding affinities. Compound 13d was further profiled for drug-like properties and for an in vitro comparison with conivaptan, the program’s mixed V1a/V2-receptor antagonist standard. 相似文献
99.
Bo-Young Lee Aimee E Howe Matthew A Conte Helena D'Cotta Elodie Pepey Jean-Francois Baroiller Federica di Palma Karen L Carleton Thomas D Kocher 《BMC genomics》2010,11(1):278
Background
Large collections of expressed sequence tags (ESTs) are a fundamental resource for analysis of gene expression and annotation of genome sequences. We generated 116,899 ESTs from 17 normalized and two non-normalized cDNA libraries representing 16 tissues from tilapia, a cichlid fish widely used in aquaculture and biological research.Results
The ESTs were assembled into 20,190 contigs and 36,028 singletons for a total of 56,218 unique sequences and a total assembled length of 35,168,415 bp. Over the whole project, a unique sequence was discovered for every 2.079 sequence reads. 17,722 (31.5%) of these unique sequences had significant BLAST hits (e-value < 10-10) to the UniProt database.Conclusion
Normalization of the cDNA pools with double-stranded nuclease allowed us to efficiently sequence a large collection of ESTs. These sequences are an important resource for studies of gene expression, comparative mapping and annotation of the forthcoming tilapia genome sequence.100.
Jessica B Spencer Aimee S Browne Susannah D Copland Donna R Session 《Reproductive biology and endocrinology : RB&E》2010,8(1):1-3