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61.
Contribution of crop model structure,parameters and climate projections to uncertainty in climate change impact assessments 总被引:2,自引:0,他引:2 下载免费PDF全文
Fulu Tao Reimund P. Rötter Taru Palosuo Carlos Gregorio Hernández Díaz‐Ambrona M. Inés Mínguez Mikhail A. Semenov Kurt Christian Kersebaum Claas Nendel Xenia Specka Holger Hoffmann Frank Ewert Anaelle Dambreville Pierre Martre Lucía Rodríguez Margarita Ruiz‐Ramos Thomas Gaiser Jukka G. Höhn Tapio Salo Roberto Ferrise Marco Bindi Davide Cammarano Alan H. Schulman 《Global Change Biology》2018,24(3):1291-1307
Climate change impact assessments are plagued with uncertainties from many sources, such as climate projections or the inadequacies in structure and parameters of the impact model. Previous studies tried to account for the uncertainty from one or two of these. Here, we developed a triple‐ensemble probabilistic assessment using seven crop models, multiple sets of model parameters and eight contrasting climate projections together to comprehensively account for uncertainties from these three important sources. We demonstrated the approach in assessing climate change impact on barley growth and yield at Jokioinen, Finland in the Boreal climatic zone and Lleida, Spain in the Mediterranean climatic zone, for the 2050s. We further quantified and compared the contribution of crop model structure, crop model parameters and climate projections to the total variance of ensemble output using Analysis of Variance (ANOVA). Based on the triple‐ensemble probabilistic assessment, the median of simulated yield change was ?4% and +16%, and the probability of decreasing yield was 63% and 31% in the 2050s, at Jokioinen and Lleida, respectively, relative to 1981–2010. The contribution of crop model structure to the total variance of ensemble output was larger than that from downscaled climate projections and model parameters. The relative contribution of crop model parameters and downscaled climate projections to the total variance of ensemble output varied greatly among the seven crop models and between the two sites. The contribution of downscaled climate projections was on average larger than that of crop model parameters. This information on the uncertainty from different sources can be quite useful for model users to decide where to put the most effort when preparing or choosing models or parameters for impact analyses. We concluded that the triple‐ensemble probabilistic approach that accounts for the uncertainties from multiple important sources provide more comprehensive information for quantifying uncertainties in climate change impact assessments as compared to the conventional approaches that are deterministic or only account for the uncertainties from one or two of the uncertainty sources. 相似文献
62.
63.
Volkov AN Ferrari D Worrall JA Bonvin AM Ubbink M 《Protein science : a publication of the Protein Society》2005,14(3):799-811
The interaction of bovine microsomal ferricytochrome b5 with yeast iso-1-ferri and ferrocytochrome c has been investigated using heteronuclear NMR techniques. Chemical-shift perturbations for 1H and 15N nuclei of both cytochromes, arising from the interactions with the unlabeled partner proteins, were used for mapping the interacting surfaces on both proteins. The similarity of the binding shifts observed for oxidized and reduced cytochrome c indicates that the complex formation is not influenced by the oxidation state of the cytochrome c. Protein-protein docking simulations have been performed for the binary cytochrome b5-cytochrome c and ternary (cytochrome b5)-(cytochrome c)2 complexes using a novel HADDOCK approach. The docking procedure, which makes use of the experimental data to drive the docking, identified a range of orientations assumed by the proteins in the complex. It is demonstrated that cytochrome c uses a confined surface patch for interaction with a much more extensive surface area of cytochrome b5. Taken together, the experimental data suggest the presence of a dynamic ensemble of conformations assumed by the proteins in the complex. 相似文献
64.
Dinsmore CJ Zartman CB Bergman JM Abrams MT Buser CA Culberson JC Davide JP Ellis-Hutchings M Fernandes C Graham SL Hartman GD Huber HE Lobell RB Mosser SD Robinson RG Williams TM 《Bioorganic & medicinal chemistry letters》2004,14(3):639-643
A series of macrocyclic piperazinone compounds with dual farnesyltransferase/geranylgeranyltransferase-I inhibitory activity was prepared. These compounds were found to be potent inhibitors of protein prenylation in cell culture. A hypothesis for the binding mode of compound 3o in FPTase is proposed. 相似文献
65.
Federica Susta Davide Chiasserini Katia Fettucciari Pier Luigi Orvietani Flavia Quotadamo Rosina Noce Andrea Bartoli Pierfrancesco Marconi Lanfranco Corazzi Luciano Binaglia 《Proteomics》2010,10(11):2099-2112
Protein expression changes induced in thioglycolate‐elicited peritoneal murine macrophages (MΦ) by infection with type III Group B Streptococcus (GBS) are described. Proteins from control MΦ and MΦ incubated 2 h with live or heat‐inactivated GBS were separated by 2‐DE. Proteins whose expression was significantly different in infected MΦ, as compared with control cells, were identified by MS/MS analysis. Changes in the expression level of proteins involved in both positive and negative modulation of phagocytic functions, stress response and cell death were induced in MΦ by GBS infection. In particular, expression of enzymes playing a key role in production of reactive oxygen species was lowered in GBS‐infected MΦ. Significant alterations in the expression of some metabolic enzymes were also observed, most of the glycolytic and of the pentose‐cycle enzymes being down‐regulated in MΦ infected with live GBS. Finally, evidence was obtained that GBS infection affects the expression of enzymes or enzyme subunits involved in ATP synthesis and in adenine nucleotides interconversion processes. 相似文献
66.
Khawar Sohail Siddiqui Don M. Parkin Paul M. G. Curmi Davide De Francisci Anne Poljak Kevin Barrow Malcolm H. Noble Jill Trewhella Ricardo Cavicchioli 《Biotechnology and bioengineering》2009,103(4):676-686
The alkaline protease, savinase was chemically modified to enhance the productivity of the enzyme at low temperatures on a complex polymeric protein (azocasein) substrate. At 5 and 15°C, savinase modified with ficol or dextran hydrolyzed fivefold more azocasein than the unmodified savinase. Kinetic studies showed that the catalytic improvements are associated with changes in uncompetitive substrate inhibition with Ki values of modified savinases sixfold higher than the unmodified savinase. Modeling of small‐angle scattering data indicates that two substrate molecules bind on opposing sides of the enzyme. The combined kinetic and structural data indicate that the polysaccharide modifier sterically blocks the allosteric site and reduces substrate inhibition. In contrast to the properties of cold‐active enzymes that generally manifest as low activation enthalpy and high flexibility, this study shows that increased activity and productivity at low temperature can be achieved by reducing uncompetitive substrate inhibition, and that this can be achieved using chemical modification with an enzyme in a commercial enzyme‐formulation. Biotechnol. Bioeng. 2009;103: 676–686. © 2009 Wiley Periodicals, Inc. 相似文献
67.
Barbara Salani Silvia Ravera Adriana Amaro Annalisa Salis Mario Passalacqua Enrico Millo Gianluca Damonte Cecilia Marini Ulrich Pfeffer Gianmario Sambuceti Renzo Cordera Davide Maggi 《Cell cycle (Georgetown, Tex.)》2015,14(10):1559-1567
Pyruvate kinase M2 (PKM2) acts at the crossroad of growth and metabolism pathways in cells. PKM2 regulation by growth factors can redirect glycolytic intermediates into key biosynthetic pathway. Here we show that IGF1 can regulate glycolysis rate, stimulate PKM2 Ser/Thr phosphorylation and decrease cellular pyruvate kinase activity. Upon IGF1 treatment we found an increase of the dimeric form of PKM2 and the enrichment of PKM2 in the nucleus. This effect was associated to a reduction of pyruvate kinase enzymatic activity and was reversed using metformin, which decreases Akt phosphorylation. IGF1 induced an increased nuclear localization of PKM2 and STAT3, which correlated with an increased HIF1α, HK2, and GLUT1 expression and glucose entrapment. Metformin inhibited HK2, GLUT1, HIF-1α expression and glucose consumption. These findings suggest a role of IGFIR/Akt axis in regulating glycolysis by Ser/Thr PKM2 phosphorylation in cancer cells. 相似文献
68.
Borcard F Godinat A Staedler D Blanco HC Dumont AL Chapuis-Bernasconi C Scaletta C Applegate LA Juillerat FK Gonzenbach UT Gerber-Lemaire S Juillerat-Jeanneret L 《Bioconjugate chemistry》2011,22(7):1422-1432
The chemical functionalization of cell-surface proteins of human primary fetal bone cells with hydrophilic bioorthogonal intermediates was investigated. Toward this goal, chemical pathways were developed for click reaction-mediated coupling of alkyne derivatives with cellular azido-expressing proteins. The incorporation via a tetraethylene glycol linker of a dipeptide and a reporter biotin allowed the proof of concept for the introduction of cell-specific peptide ligands and allowed us to follow the reaction in living cells. Tuning the conditions of the click reaction resulted in chemical functionalization of living human fetal osteoblasts with excellent cell survival. 相似文献
69.
Microbiology in the post-genomic era 总被引:1,自引:0,他引:1
Medini D Serruto D Parkhill J Relman DA Donati C Moxon R Falkow S Rappuoli R 《Nature reviews. Microbiology》2008,6(6):419-430
Genomics has revolutionized every aspect of microbiology. Now, 13 years after the first bacterial genome was sequenced, it is important to pause and consider what has changed in microbiology research as a consequence of genomics. In this article, we review the evolving field of bacterial typing and the genomic technologies that enable comparative analysis of multiple genomes and the metagenomes of complex microbial environments, and address the implications of the genomic era for the future of microbiology. 相似文献
70.
Davide Facchinelli Gessica Marchesini Gianpaolo Nadali Livio Pagano 《Current fungal infection reports》2018,12(4):179-186