Community-wide analysis of microbial genome sequence signatures (2009)
Dick, Gregory J, Andersson, Anders F, Baker, Brett J, Simmons, Sheri L, Thomas, Brian C, Yelton, A Pepper, ...
Abstract Background Analyses of DNA sequences from cultivated microorganisms have revealed genome-wide, taxa-specific nucleotide compositional characteristics, referred to as genome signatures. These...
Cometary airbursts and atmospheric chemistry: Tunguska and a candidate Younger Dryas event (2009)
Melott, Adrian L., Thomas, Brian C., Dreschhoff, Gisela, Johnson, Carey K.
We estimate atmospheric chemistry changes from ionization for the 1908 Tunguska airburst event, finding agreement with nitrate enhancement in GISP2H and GISP2 ice cores, noting an unexplained...
Gamma-Ray Bursts as a Threat to Life on Earth (2009)
Gamma-ray bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. The gamma radiation from a burst within a few kiloparsecs would quickly...
Melott, Adrian L., Thomas, Brian C.
Based on the intensity and rates of various kinds of intense ionizing radiation events such as supernovae and gamma-ray bursts, it is likely that the Earth has been subjected to one or extinction...
Thomas, Brian C., Honeyman, Michelle D.
It is known that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources...
A Lookup Table to Compute High Energy Cosmic Ray Effects on Terrestrial Atmospheric Chemistry (2008)
Melott, Adrian L., Atri, Dimitra, Thomas, Brian C., Krejci, Alex J., U), Washburn
A variety of events such as gamma-ray bursts and supernovae may expose the Earth to an increased flux of high-energy cosmic rays, with potentially important effects on the biosphere. Existing...
An In-Class Discussion Activity on the Nature of Science and Intelligent Design (2007)
In this paper I describe an in-class discussion activity aimed at helping elementary education majors in a physical science course think about issues surrounding the inclusion of "Intelligent Design"...
Superluminous supernovae: No threat from Eta Carinae (2007)
Thomas, Brian C., Melott, Adrian L., Fields, Brian D., Anthony-Twarog, Barbara J.
Recently Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of ~10^44 Joules. It was proposed that the progenitor may have been a massive evolved star similar...
Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events (2006)
Ejzak, Larissa M., Melott, Adrian L., Medvedev, Mikhail V., Thomas, Brian C.
Gamma-Ray Bursts (GRBs) directed at Earth from within a few kpc may have damaged the biosphere, primarily though changes in atmospheric chemistry which admit greatly increased Solar UV. However, GRBs...
Gamma-ray bursts and terrestrial planetary atmospheres (2006)
Thomas, Brian C., Melott, Adrian L.
We describe results of modeling the effects on Earth-like planets of long-duration gamma-ray bursts (GRBs) within a few kiloparsecs. A primary effect is generation of nitrogen oxide compounds which...
Freeling, Michael, Thomas, Brian C.
Controversy surrounds the apparent rising maximums of morphological complexity during eukaryotic evolution, with organisms increasing the number and nestedness of developmental areas as evidenced by...
Thomas, Brian C., Pedersen, Brent, Freeling, Michael
Approximately 90% of Arabidopsis’ unique gene content is found in syntenic blocks that were formed during the most recent whole-genome duplication. Within these blocks, 28.6% of the genes have a...
Thomas, Brian C., Pedersen, Brent, Freeling, Michael
Approximately 90% of Arabidopsis’ unique gene content is found in syntenic blocks that were formed during the most recent whole-genome duplication. Within these blocks, 28.6% of the genes have a...
Thomas, Brian C., Melott, Adrian L., Jackman, Charles H., Laird, Claude M., Medvedev, Mikhail V., Stolarski, Richard S., ...
Gamma-Ray Bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. We have used a two-dimensional atmospheric model to investigate the effects...
Climatic and Biogeochemical Effects of a Galactic Gamma-Ray Burst (2005)
Melott, Adrian L., Thomas, Brian C., Hogan, Daniel P., Ejzak, Larissa M., Jackman, Charles H.
It is likely that one or more gamma-ray bursts within our galaxy have strongly irradiated the Earth in the last Gy. This produces significant atmospheric ionization and dissociation, resulting in...
Terrestrial ozone depletion due to a Milky Way Gamma-Ray Burst / (2005)
Thesis (Ph. D.)--University of Kansas, Physics and Astronomy, 2005.
Terrestrial Ozone Depletion Due to a Milky Way Gamma-Ray Burst (2004)
Thomas, Brian C., Jackman, Charles H., Melott, Adrian L., Laird, Claude M., Stolarski, Richard S., Gehrels, Neil, ...
Based on cosmological rates, it is probable that at least once in the last Gy the Earth has been irradiated by a gamma-ray burst in our Galaxy from within 2 kpc. Using a two-dimensional atmospheric...
Quantifying the Bull's Eye Effect (2003)
Thomas, Brian C., Melott, Adrian L., Feldman, Hume A., Shandarin, Sergei F.
We have used N-body simulations to develop two independent methods to quantify redshift distortions known as the Bull's Eye effect (large scale infall plus small scale virial motion). This effect...
Conserved Noncoding Sequences in the Grasses (2003)
Inada, Dan Choffnes, Bashir, Ali, Lee, Chunghau, Thomas, Brian C., Ko, Cynthia, Goff, Stephen A., ...
As orthologous genes from related species diverge over time, some sequences are conserved in noncoding regions. In mammals, large phylogenetic footprints, or conserved noncoding sequences (CNSs), are...
Thesis (B.S.)--Pennsylvania State University.
Conserved Noncoding Sequences in the Grasses4
Inada, Dan Choffnes, Bashir, Ali, Lee, Chunghau, Thomas, Brian C., Ko, Cynthia, Goff, Stephen A., ...
As orthologous genes from related species diverge over time, some sequences are conserved in noncoding regions. In mammals, large phylogenetic footprints, or conserved noncoding sequences (CNSs), are...
Conserved Noncoding Sequences in the Grasses4
Inada, Dan Choffnes, Bashir, Ali, Lee, Chunghau, Thomas, Brian C., Ko, Cynthia, Goff, Stephen A., ...
As orthologous genes from related species diverge over time, some sequences are conserved in noncoding regions. In mammals, large phylogenetic footprints, or conserved noncoding sequences (CNSs), are...
Thomas, Brian C., Pedersen, Brent, Freeling, Michael
Approximately 90% of Arabidopsis’ unique gene content is found in syntenic blocks that were formed during the most recent whole-genome duplication. Within these blocks, 28.6% of the genes have a...
Arabidopsis intragenomic conserved noncoding sequence
Thomas, Brian C., Rapaka, Lakshmi, Lyons, Eric, Pedersen, Brent, Freeling, Michael
After the most recent tetraploidy in the Arabidopsis lineage, most gene pairs lost one, but not both, of their duplicates. We manually inspected the 3,179 retained gene pairs and their surrounding...
Freeling, Michael, Rapaka, Lakshmi, Lyons, Eric, Pedersen, Brent, Thomas, Brian C.
A tetraploidy left Arabidopsis thaliana with 6358 pairs of homoeologs that, when aligned, generated 14,944 intragenomic conserved noncoding sequences (CNSs). Our previous work assembled these...
Community-wide analysis of microbial genome sequence signatures
Dick, Gregory J, Andersson, Anders F, Baker, Brett J, Simmons, Sheri L, Thomas, Brian C, Yelton, A Pepper, ...
Genome signatures are used to identify and cluster sequences de novo from an acid biofilm microbial community metagenomic dataset, revealing information about the low-abundance community members.