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Average Contributions (average + contribution)
Selected AbstractsEstimation of suspended sediment sources using 137Cs and 210Pbex in unmanaged Japanese cypress plantation watersheds in southern JapanHYDROLOGICAL PROCESSES, Issue 23 2008Shigeru Mizugaki Abstract To analyse suspended sediment sources in unmanaged Japanese cypress plantation watersheds, field measurements and fingerprinting of the suspended sediment was conducted in the Shimanto River basin in southern Japan. For sediment fingerprinting, 137Cs and 210Pbex were detected by means of gamma-ray spectrometry in the surface soil of the forest floor, stream bank and truck trail and mobilized sediment by interrill erosion. The 137Cs and 210Pbex activities associated with the forest floor materials were considerably higher than those of the stream bank and truck trail. The 137Cs and 210Pbex activities associated with the suspended sediment were found to vary with the sampling period. Evidently, the suspended sediment can comprise materials generated from the forest floor by interrill erosion and those from the truck trail and/or stream bank. The multivariate sediment-mixing model using 137Cs and 210Pbex showed that the contribution of the forest floor varied periodically, ranging from 23,56% in the Hinoki 156 subwatershed and from 18,85% in the Hinoki 155 subwatershed. The difference in the average contribution of the forest floor between Hinoki 156 (46%) and Hinoki 155 (69%) may relate to the presence of truck trail networks in the watershed. The truck trail network can play roles of sediment source and pathway for sediment from forest floor to stream channel due to the concentrated overland flow on the truck trail during heavy rainfall events. These results indicate that the forest floor should be recognized as a major source of suspended sediment in unmanaged Japanese cypress plantation watersheds. Copyright © 2008 John Wiley & Sons, Ltd. [source] DATE analysis: A general theory of biological change applied to microarray dataBIOTECHNOLOGY PROGRESS, Issue 5 2009David Rasnick Abstract In contrast to conventional data mining, which searches for specific subsets of genes (extensive variables) to correlate with specific phenotypes, DATE analysis correlates intensive state variables calculated from the same datasets. At the heart of DATE analysis are two biological equations of state not dependent on genetic pathways. This result distinguishes DATE analysis from other bioinformatics approaches. The dimensionless state variable F quantifies the relative overall cellular activity of test cells compared to well-chosen reference cells. The variable ,i is the fold-change in the expression of the ith gene of test cells relative to reference. It is the fraction , of the genome undergoing differential expression,not the magnitude ,,that controls biological change. The state variable , is equivalent to the control strength of metabolic control analysis. For tractability, DATE analysis assumes a linear system of enzyme-connected networks and exploits the small average contribution of each cellular component. This approach was validated by reproducible values of the state variables F, RNA index, and , calculated from random subsets of transcript microarray data. Using published microarray data, F, RNA index, and , were correlated with: (1) the blood-feeding cycle of the malaria parasite, (2) embryonic development of the fruit fly, (3) temperature adaptation of Killifish, (4) exponential growth of cultured S. pneumoniae, and (5) human cancers. DATE analysis was applied to aCGH data from the great apes. A good example of the power of DATE analysis is its application to genomically unstable cancers, which have been refractory to data mining strategies. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Protein,membrane interactions: blood clotting on nanoscale bilayersJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009J. H. MORRISSEY Summary., The clotting cascade requires the assembly of protease,cofactor complexes on membranes with exposed anionic phospholipids. Despite their importance, protein,membrane interactions in clotting remain relatively poorly understood. Calcium ions are known to induce anionic phospholipids to cluster, and we propose that clotting proteins assemble preferentially on such anionic lipid-rich microdomains. Until recently, there was no way to control the partitioning of clotting proteins into or out of specific membrane microdomains, so experimenters only knew the average contributions of phospholipids to blood clotting. The development of nanoscale membrane bilayers (Nanodiscs) has now allowed us to probe, with nanometer resolution, how local variations in phospholipid composition regulate the activity of key protease,cofactor complexes in blood clotting. Furthermore, exciting new progress in solid-state NMR and large-scale molecular dynamics simulations allow structural insights into interactions between proteins and membrane surfaces with atomic resolution. [source] Recognizing large donations to public goods: an experimental testMANAGERIAL AND DECISION ECONOMICS, Issue 1 2002Jeremy Clark Private charities often publicise generous individual contributions or contributors, possibly to encourage others to give. In contrast, public good experiments used to study voluntary giving commonly tell participants only of total contributions. This paper reports an experimental test of the effect on contributions of supplying additional selective information. A control treatment is run that reveals only total contributions over ten one-shot decision rounds. This is compared to a second treatment that also informs subjects of the maximum contribution made in their group after each round. In a third treatment, subjects are further given the opportunity to make costly rewards to the maximum contributor. Revealing generous contributions appears to raise average contributions slightly. Surprisingly, adding the ability to reward large contributors does little to generate further increases, though it significantly raises the variance of contributions. Copyright © 2002 John Wiley & Sons, Ltd. [source] Nutrient enrichment overwhelms diversity effects in leaf decomposition by stream fungiOIKOS, Issue 2 2003Felix Bärlocher Mass losses of oak leaves were studied in microcosms, where numbers of aquatic hyphomycete species (1,5) and nutrient concentrations (2 levels each of N, P, and Ca) were varied. Species numbers, species identities, N, P and N×P interactions all had significant effects on leaf mass loss, but the magnitude of the effect was greater for N and P than for species numbers. Mass loss in multicultures was greater than predicted from average contributions of the component species in single cultures. This may have been due to sampling effects or niche complementarity. [source] | ||||||||||