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141.
VERITAS Collaboration Aliu E Arlen T Aune T Beilicke M Benbow W Bouvier A Bradbury SM Buckley JH Bugaev V Byrum K Cannon A Cesarini A Christiansen JL Ciupik L Collins-Hughes E Connolly MP Cui W Dickherber R Duke C Errando M Falcone A Finley JP Finnegan G Fortson L Furniss A Galante N Gall D Gibbs K Gillanders GH Godambe S Griffin S Grube J Guenette R Gyuk G Hanna D Holder J Huan H Hughes G Hui CM Humensky TB Imran A Kaaret P Karlsson N Kertzman M Kieda D Krawczynski H Krennrich F Lang MJ 《Science (New York, N.Y.)》2011,334(6052):69-72
We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star. 相似文献
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Hoskins RA Nelson CR Berman BP Laverty TR George RA Ciesiolka L Naeemuddin M Arenson AD Durbin J David RG Tabor PE Bailey MR DeShazo DR Catanese J Mammoser A Osoegawa K de Jong PJ Celniker SE Gibbs RA Rubin GM Scherer SE 《Science (New York, N.Y.)》2000,287(5461):2271-2274
We constructed a bacterial artificial chromosome (BAC)-based physical map of chromosomes 2 and 3 of Drosophila melanogaster, which constitute 81% of the genome. Sequence tagged site (STS) content, restriction fingerprinting, and polytene chromosome in situ hybridization approaches were integrated to produce a map spanning the euchromatin. Three of five remaining gaps are in repeat-rich regions near the centromeres. A tiling path of clones spanning this map and STS maps of chromosomes X and 4 was sequenced to low coverage; the maps and tiling path sequence were used to support and verify the whole-genome sequence assembly, and tiling path BACs were used as templates in sequence finishing. 相似文献
144.
Rhesus Macaque Genome Sequencing Analysis Consortium Gibbs RA Rogers J Katze MG Bumgarner R Weinstock GM Mardis ER Remington KA Strausberg RL Venter JC Wilson RK Batzer MA Bustamante CD Eichler EE Hahn MW Hardison RC Makova KD Miller W Milosavljevic A Palermo RE Siepel A Sikela JM Attaway T Bell S Bernard KE Buhay CJ Chandrabose MN Dao M Davis C Delehaunty KD Ding Y Dinh HH Dugan-Rocha S Fulton LA Gabisi RA Garner TT Godfrey J Hawes AC Hernandez J Hines S Holder M Hume J Jhangiani SN 《Science (New York, N.Y.)》2007,316(5822):222-234
145.
Transmission of equine influenza virus to dogs 总被引:1,自引:0,他引:1
Crawford PC Dubovi EJ Castleman WL Stephenson I Gibbs EP Chen L Smith C Hill RC Ferro P Pompey J Bright RA Medina MJ Johnson CM Olsen CW Cox NJ Klimov AI Katz JM Donis RO 《Science (New York, N.Y.)》2005,310(5747):482-485
Molecular and antigenic analyses of three influenza viruses isolated from outbreaks of severe respiratory disease in racing greyhounds revealed that they are closely related to H3N8 equine influenza virus. Phylogenetic analysis indicated that the canine influenza virus genomes form a monophyletic group, consistent with a single interspecies virus transfer. Molecular changes in the hemagglutinin suggested adaptive evolution in the new host. The etiologic role of this virus in respiratory disease was supported by the temporal association of rising antibody titers with disease and by experimental inoculation studies. The geographic expansion of the infection and its persistence for several years indicate efficient transmission of canine influenza virus among greyhounds. Evidence of infection in pet dogs suggests that this infection may also become enzootic in this population. 相似文献
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Gibbs CS 《Science (New York, N.Y.)》1935,81(2101):345-346
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