Institution
Oregon State University
Education•Corvallis, Oregon, United States•
About: Oregon State University is a education organization based out in Corvallis, Oregon, United States. It is known for research contribution in the topics: Population & Climate change. The organization has 28192 authors who have published 64044 publications receiving 2634108 citations. The organization is also known as: Oregon Agricultural College & OSU.
Topics: Population, Climate change, Gene, Upwelling, Soil water
Papers published on a yearly basis
Papers
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TL;DR: Test case prioritization techniques schedule test cases for execution in an order that attempts to increase their effectiveness at meeting some performance goal as discussed by the authors, such as rate of fault detection, a measure of how quickly faults are detected within the testing process.
Abstract: Test case prioritization techniques schedule test cases for execution in an order that attempts to increase their effectiveness at meeting some performance goal. Various goals are possible; one involves rate of fault detection, a measure of how quickly faults are detected within the testing process. An improved rate of fault detection during testing can provide faster feedback on the system under test and let software engineers begin correcting faults earlier than might otherwise be possible. One application of prioritization techniques involves regression testing, the retesting of software following modifications; in this context, prioritization techniques can take advantage of information gathered about the previous execution of test cases to obtain test case orderings. We describe several techniques for using test execution information to prioritize test cases for regression testing, including: 1) techniques that order test cases based on their total coverage of code components; 2) techniques that order test cases based on their coverage of code components not previously covered; and 3) techniques that order test cases based on their estimated ability to reveal faults in the code components that they cover. We report the results of several experiments in which we applied these techniques to various test suites for various programs and measured the rates of fault detection achieved by the prioritized test suites, comparing those rates to the rates achieved by untreated, randomly ordered, and optimally ordered suites.
1,200 citations
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TL;DR: Using microarray analysis, it is shown that heterochromatin in Arabidopsis is determined by transposable elements and related tandem repeats, under the control of the chromatin remodelling ATPase DDM1 (Decrease in DNA Methylation 1).
Abstract: Heterochromatin has been defined as deeply staining chromosomal material that remains condensed in interphase, whereas euchromatin undergoes de-condensation. Heterochromatin is found near centromeres and telomeres, but interstitial sites of heterochromatin (knobs) are common in plant genomes and were first described in maize. These regions are repetitive and late-replicating. In Drosophila, heterochromatin influences gene expression, a heterochromatin phenomenon called position effect variegation. Similarities between position effect variegation in Drosophila and gene silencing in maize mediated by "controlling elements" (that is, transposable elements) led in part to the proposal that heterochromatin is composed of transposable elements, and that such elements scattered throughout the genome might regulate development. Using microarray analysis, we show that heterochromatin in Arabidopsis is determined by transposable elements and related tandem repeats, under the control of the chromatin remodelling ATPase DDM1 (Decrease in DNA Methylation 1). Small interfering RNAs (siRNAs) correspond to these sequences, suggesting a role in guiding DDM1. We also show that transposable elements can regulate genes epigenetically, but only when inserted within or very close to them. This probably accounts for the regulation by DDM1 and the DNA methyltransferase MET1 of the euchromatic, imprinted gene FWA, as its promoter is provided by transposable-element-derived tandem repeats that are associated with siRNAs.
1,199 citations
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Oregon State University1, University of Bayreuth2, University of California, Berkeley3, Climate Monitoring and Diagnostics Laboratory4, Institut national de la recherche agronomique5, University of Minnesota6, Wageningen University and Research Centre7, University of California, Davis8, University of Virginia9, Swedish University of Agricultural Sciences10, United States Department of Agriculture11, University of Antwerp12, University of Edinburgh13, Technical University of Denmark14, Duke University15, Tuscia University16, Oak Ridge National Laboratory17, University of Colorado Boulder18, Harvard University19, San Diego State University20, University of Nebraska–Lincoln21, University of Helsinki22
TL;DR: The authors compared seasonal and annual estimates of CO2 and water vapor exchange across sites in forests, grasslands, crops, and tundra that are part of an international network called FLUXNET, and investigated the responses of vegetation to environmental variables.
1,199 citations
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TL;DR: In this paper, a simple formulation of the boundary layer is developed for use in large-scale models and other situations where simplicity is required, where some resolution is possible within the boundary layers, but where the resolution is insufficient for resolving the detailed boundary-layer structure and overlying capping inversion.
Abstract: A simple formulation of the boundary layer is developed for use in large-scale models and other situations where simplicity is required. The formulation is suited for use in models where some resolution is possible within the boundary layer, but where the resolution is insufficient for resolving the detailed boundary-layer structure and overlying capping inversion. Surface fluxes are represented in terms of similarity theory while turbulent diffusivities above the surface layer are formulated in terms of bulk similarity considerations and matching conditions at the top of the surface layer. The boundary-layer depth is expressed in terms of a bulk Richardson number which is modified to include the influence of thermals. Attention is devoted to the interrelationship between predicted boundary-layer growth, the turbulent diffusivity profile, ‘countergradient’ heat flux and truncation errors. The model predicts growth of the convectively mixed layer reasonably well and is well-behaved in cases of weak surface heat flux and transitions between stable and unstable cases. The evolution of the modelled boundary layer is studied for different ratios of surface evaporation to potential evaporation. Typical variations of surface evaporation result in a much greater variation in boundary-layer depth than that caused by the choice of the boundary-layer depth formulation.
1,195 citations
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University of Tennessee1, Oak Ridge National Laboratory2, University of Georgia3, University of Wyoming4, Michigan State University5, Marine Biological Laboratory6, University of Notre Dame7, Oregon State University8, University of New Mexico9, Kansas State University10, Arizona State University11, United States Department of Agriculture12, University of New Hampshire13, Virginia Tech14, Washington State University Vancouver15, Ball State University16
TL;DR: It is demonstrated that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.
Abstract: About a quarter of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating substantial sinks for nitrogen must exist in the landscape. Data from nitrogen stable isotope tracer experiments across 72 streams suggests that the total uptake of nitrate is related to ecosystem photosynthesis, and that denitrification is related to ecosystem respiration. A stream network model demonstrates that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks. Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing1,2 and terrestrial ecosystems are becoming increasingly nitrogen-saturated3, causing more bioavailable nitrogen to enter groundwater and surface waters4,5,6. Large-scale nitrogen budgets show that an average of about 20–25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins7,8, indicating that substantial sinks for nitrogen must exist in the landscape9. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification6,10,11. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.
1,193 citations
Authors
Showing all 28447 results
Name | H-index | Papers | Citations |
---|---|---|---|
Robert Stone | 160 | 1756 | 167901 |
Menachem Elimelech | 157 | 547 | 95285 |
Thomas J. Smith | 140 | 1775 | 113919 |
Harold A. Mooney | 135 | 450 | 100404 |
Jerry M. Melillo | 134 | 383 | 68894 |
John F. Thompson | 132 | 1420 | 95894 |
Thomas N. Williams | 132 | 1145 | 95109 |
Peter M. Vitousek | 127 | 352 | 96184 |
Steven W. Running | 126 | 355 | 76265 |
Vincenzo Di Marzo | 126 | 659 | 60240 |
J. D. Hansen | 122 | 975 | 76198 |
Peter Molnar | 118 | 446 | 53480 |
Michael R. Hoffmann | 109 | 500 | 63474 |
David Pollard | 108 | 438 | 39550 |
David J. Hill | 107 | 1364 | 57746 |