Institution
Denison University
Education•Granville, Ohio, United States•
About: Denison University is a education organization based out in Granville, Ohio, United States. It is known for research contribution in the topics: Population & Politics. The organization has 921 authors who have published 1828 publications receiving 41060 citations. The organization is also known as: Denison & DU.
Papers published on a yearly basis
Papers
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TL;DR: In this paper, a rain-event driven, process-oriented model of nitrogen and carbon cycling processes in soils was used to simulate N2O and CO2 emissions from soils.
Abstract: Simulations of N2O and CO2 emissions from soils were conducted with a rain-event driven, process-oriented model (DNDC) of nitrogen and carbon cycling processes in soils. The magnitude and trends of simulated N2O (or N2O + N2) and CO2 emissions were consistent with the results obtained in field experiments. The successful simulation of these emissions from the range of soil types examined demonstrates that the DNDC will be a useful tool for the study of linkages among climate, soil-atmosphere interactions, land use, and trace gas fluxes.
1,243 citations
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TL;DR: Previous results about the classical information capacity of a noiseless quantum-mechanical communication channel are extended to situations in which the final signal states are mixed states, that is, to channels with noise.
Abstract: This paper extends previous results about the classical information capacity of a noiseless quantum-mechanical communication channel to situations in which the final signal states are mixed states, that is, to channels with noise.
1,159 citations
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Smithsonian Institution1, Sun Yat-sen University2, University of California, Berkeley3, Naturalis4, Paris-Sorbonne University5, Universidade Federal de Minas Gerais6, University of Vermont7, Federal University of Western Pará8, University of Florida9, James Cook University10, Duke University11, University of Bonn12, University of Neuchâtel13, University of Turku14, University of Alaska Fairbanks15, Missouri Botanical Garden16, National Taiwan University17, Museum of New Zealand Te Papa Tongarewa18, National University of Río Cuarto19, University of Arizona20, Council of Agriculture21, Kaohsiung Medical University22, Chongqing Normal University23, Universidade Federal de Juiz de Fora24, Nanjing Forestry University25, Iowa State University26, Complutense University of Madrid27, University of Kansas28, Denison University29, University of Zurich30
TL;DR: A modern, comprehensive classification for lycophytes and ferns, down to the genus level, utilizing a community‐based approach, that uses monophyly as the primary criterion for the recognition of taxa, but also aims to preserve existing taxa and circumscriptions that are both widely accepted and consistent with the understanding of pteridophyte phylogeny.
Abstract: Phylogeny has long informed pteridophyte classification. As our ability to infer evolutionary trees has improved, classifications aimed at recognizing natural groups have become increasingly predic ...
971 citations
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TL;DR: In this article, the jet kinematics of a complete flux-density-limited sample of 135 radio-loud active galactic nuclei (AGNs) resulting from a 13-year program to investigate the structure and evolution of parsec-scale jet phenomena are discussed.
Abstract: We discuss the jet kinematics of a complete flux-density-limited sample of 135 radio-loud active galactic nuclei (AGNs) resulting from a 13 year program to investigate the structure and evolution of parsec-scale jet phenomena. Our analysis is based on new 2 cm Very Long Baseline Array (VLBA) images obtained between 2002 and 2007, but includes our previously published observations made at the same wavelength, and is supplemented by VLBA archive data. In all, we have used 2424 images spanning the years 1994-2007 to study and determine the motions of 526 separate jet features in 127 jets. The data quality and temporal coverage (a median of 15 epochs per source) of this complete AGN jet sample represent a significant advance over previous kinematics surveys. In all but five AGNs, the jets appear one-sided, most likely the result of differential Doppler boosting. In general, the observed motions are directed along the jet ridge line, outward from the optically thick core feature. We directly observe changes in speed and/or direction in one third of the well-sampled jet components in our survey. While there is some spread in the apparent speeds of separate features within an individual jet, the dispersion is about three times smaller than the overall dispersion of speeds among all jets. This supports the idea that there is a characteristic flow that describes each jet, which we have characterized by the fastest observed component speed. The observed maximum speed distribution is peaked at ~10c, with a tail that extends out to ~50c. This requires a distribution of intrinsic Lorentz factors in the parent population that range up to ~50. We also note the presence of some rare low-pattern speeds or even stationary features in otherwise rapidly flowing jets that may be the result of standing re-collimation shocks, and/or a complex geometry and highly favorable Doppler factor.
511 citations
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TL;DR: In this article, the parsec-scale kinematics of 200 active galactic nucleus (AGN) jets based on 15 GHz Very Long Baseline Array (VLBA) data obtained between 1994 August 31 and 2011 May 1 were described.
Abstract: We describe the parsec-scale kinematics of 200 active galactic nucleus (AGN) jets based on 15 GHz Very Long Baseline Array (VLBA) data obtained between 1994 August 31 and 2011 May 1. We present new VLBA 15 GHz images of these and 59 additional AGNs from the MOJAVE and 2 cm Survey programs. Nearly all of the 60 most heavily observed jets show significant changes in their innermost position angle over a 12-16 yr interval, ranging from 10° to 150° on the sky, corresponding to intrinsic variations of ~0.°5 to ~2°. The BL Lac jets show smaller variations than quasars. Roughly half of the heavily observed jets show systematic position angle trends with time, and 20 show indications of oscillatory behavior. The time spans of the data sets are too short compared to the fitted periods (5-12 yr), however, to reliably establish periodicity. The rapid changes and large jumps in position angle seen in many cases suggest that the superluminal AGN jet features occupy only a portion of the entire jet cross section and may be energized portions of thin instability structures within the jet. We have derived vector proper motions for 887 moving features in 200 jets having at least five VLBA epochs. For 557 well-sampled features, there are sufficient data to additionally study possible accelerations. We find that the moving features are generally non-ballistic, with 70% of the well-sampled features showing either significant accelerations or non-radial motions. Inward motions are rare (2% of all features), are slow (<0.1 mas yr–1), are more prevalent in BL Lac jets, and are typically found within 1 mas of the unresolved core feature. There is a general trend of increasing apparent speed with distance down the jet for both radio galaxies and BL Lac objects. In most jets, the speeds of the features cluster around a characteristic value, yet there is a considerable dispersion in the distribution. Orientation variations within the jet cannot fully account for the dispersion, implying that the features have a range of Lorentz factor and/or pattern speed. Very slow pattern speed features are rare, comprising only 4% of the sample, and are more prevalent in radio galaxy and BL Lac jets. We confirm a previously reported upper envelope to the distribution of speed versus beamed luminosity for moving jet features. Below 1026 W Hz–1 there is a fall-off in maximum speed with decreasing 15 GHz radio luminosity. The general shape of the envelope implies that the most intrinsically powerful AGN jets have a wide range of Lorentz factors up to ~40, while intrinsically weak jets are only mildly relativistic.
461 citations
Authors
Showing all 936 results
Name | H-index | Papers | Citations |
---|---|---|---|
Mark R. Leary | 89 | 273 | 53324 |
Janet Shibley Hyde | 83 | 227 | 38440 |
Kenneth E. Schmader | 81 | 265 | 28248 |
David Goldblatt | 66 | 309 | 13408 |
David White | 61 | 369 | 12255 |
Steven D. Doty | 47 | 97 | 5784 |
Jean R. Wrathall | 41 | 81 | 6211 |
Daniel C. Homan | 40 | 91 | 7143 |
Michael S. Barker | 37 | 99 | 7893 |
Shanan E. Peters | 36 | 84 | 4160 |
C. Judson Herrick | 34 | 92 | 4147 |
Benjamin Schumacher | 29 | 65 | 10394 |
Paul A. Djupe | 27 | 113 | 2316 |
J. Michelle Kahlenberg | 26 | 95 | 3155 |
David E. Carr | 24 | 57 | 1999 |