57,135 research outputs found

    The fossil record of early tetrapods: Worker effort and the end-Permian mass extinction

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    It is important to understand the quality of the fossil record of early tetrapods (Tetrapoda. minus Lissamphibia and Amniota) because of their key role in the transition of vertebrates from water to land, their dominance of terrestrial faunas for over 100 million years of the late Palaeozoic and early Mesozoic, and their variable fates during the end-Permian mass extinction. The first description of an early tetrapod dates back to 1824, and since then discoveries have occurred at a rather irregular pace, with peaks and troughs corresponding to some of the vicissitudes of human history through the past two centuries. As expected, the record is dominated by the well-sampled sedimentary basins of Europe and North America, but finds from other continents are increasing rapidly. Comparisons of snapshots of knowledge in 1900, 1950, and 2000 show that discovery of new species has changed the shape of the species-level diversification curve, contrary to earlier studies of family-level taxa. There is, however, little evidence that taxon counts relate to research effort (as counted by numbers of publications), and there are no biasing effects associated with differential study of different time intervals through the late Palaeozoic and Mesozoic. In fact, levels of effort are apparently not related to geological time, with no evidence that workers have spent more time on more recent parts of the record. In particular, the end-Permian mass extinction was investigated to determine whether diversity changes through that interval might reflect worker effort: it turns out that most records of early tetrapod taxa (when corrected for duration of geological series) occur in the Lower Triassic.</p

    1ST MEASUREMENT OF GAMMA(D(S)(+)-]MU+NU)/GAMMA(D(S)(+)-]PHI-PI+)

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    Complete Author List: ACOSTA D, ATHANAS M, MASEK G, PAAR H, BEAN A, GRONBERG J, KUTSCHKE R, MENARY S, MORRISON RJ, NAKANISHI S, NELSON HN, NELSON TK, RICHMAN JD, RYD A, TAJIMA H, SCHMIDT D, SPERKA D, WITHERELL MS, PROCARIO M, YANG S, BALEST R, CHO K, DAOUDI M, FORD WT, JOHNSON DR, LINGEL K, LOHNER M, RANKIN P, SMITH JG, ALEXANDER JP, BEBEK C, BERKELMAN K, BESSON D, BROWDER TE, CASSEL DG, CHO HA, COFFMAN DM, DRELL PS, EHRLICH R, GALIK RS, GARCIASCIVERES M, GEISER B, GITTELMAN B, GRAY SW, HARTILL DL, HELTSLEY BK, JONES CD, JONES SL, KANDASWAMY J, KATAYAMA N, KIM PC, KREINICK DL, LUDWIG GS, MASUI J, MEVISSEN J, MISTRY NB, NG CR, NORDBERG E, OGG M, PATTERSON JR, PETERSON D, RILEY D, SALMAN S, SAPPER M, WORDEN H, WURTHWEIN F, AVERY P, FREYBERGER A, RODRIGUEZ J, STEPHENS R, YELTON J, CINABRO D, HENDERSON S, KINOSHITA K, LIU T, SAULNIER M, SHEN F, WILSON R, YAMAMOTO H, ONG B, SELEN M, SADOFF AJ, AMMAR R, BALL S, BARINGER P, COPPAGE D, COPTY N, DAVIS R, HANCOCK N, KELLY M, KWAK N, LAM H, KUBOTA Y, LATTERY M, NELSON JK, PATTON S, PERTICONE D, POLING R, SAVINOV V, SCHRENK S, WANG R, ALAM MS, KIM IJ, NEMATI B, ONEILL JJ, SEVERINI H, SUN CR, ZOELLER MM, CRAWFORD G, DAUBENMIER CM, FULTON R, FUJINO D, GAN KK, HONSCHEID K, KAGAN H, KASS R, LEE J, MALCHOW R, MORROW F, SKOVPEN Y, SUNG M, WHITE C, WHITMORE J, WILSON P, BUTLER F, FU X, KALBFLEISCH G, LAMBRECHT M, ROSS WR, SKUBIC P, SNOW J, WANG PL, WOOD M, BORTOLETTO D, BROWN DN, FAST J, MCILWAIN RL, MIAO T, MILLER DH, MODESITT M, SCHAFFNER SF, SHIBATA EI, SHIPSEY IPJ, WANG PN, BATTLE M, ERNST J, KROHA H, ROBERTS S, SPARKS K, THORNDIKE EH, WANG CH, DOMINICK J, SANGHERA S, SHELKOV V, SKWARNICKI T, STROYNOWSKI R, VOLOBOUEV I, ZADOROZHNY P, ARTUSO M, HE D, GOLDBERG M, HORWITZ N, KENNETT R, MONETI GC, MUHEIM F, MUKHIN Y, PLAYFER S, ROZEN Y, STONE S, THULASIDAS M, VASSEUR G, ZHU G, BARTELT J, CSORNA SE, EGYED Z, JAIN V, SHELDON P, AKERIB DS, BARISH B, CHADHA M, CHAN S, COWEN DF, EIGEN G, MILLER JS, OGRADY C, URHEIM J, WEINSTEIN A

    Search for the decay Bs0→D*∓π±

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    A search for the decay Bs0→D*∓π± is presented using a data sample corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions collected by LHCb. This decay is expected to be mediated by a W-exchange diagram, with little contribution from rescattering processes, and therefore a measurement of the branching fraction will help us to understand the mechanism behind related decays such as Bs0→π+π- and Bs0→DD̅ . Systematic uncertainties are minimized by using B0→D*∓π± as a normalization channel. We find no evidence for a signal, and set an upper limit on the branching fraction of B(Bs0→D*∓π±)&#60;6.1(7.8)×10-6 at 90% (95%) confidence level

    Precision measurement of D meson mass differences

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    Using three- and four-body decays of D mesons produced in semileptonic b-hadron decays, precision measurements of D meson mass differences are made together with a measurement of the D 0 mass. The measurements are based on a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected in pp collisions at 7 TeV. Using the decay D 0 → K + K − K − π +, the D 0 mass is measured to be M(D0)=1864.75±0.15(stat)±0.11(syst)MeV/c2. The mass differences M(D+)−M(D0)=4.76±0.12(stat)±0.07(syst)MeV/c2,M(Ds)−M(D+)=98.68±0.03(stat)±0.04(syst)MeV/c2 are measured using the D 0 → K + K − π + π − and D+(s)→K+K−π+ mode

    Benton Lutheran Church, Crooks SD Minnehaha County

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    negative 35mm long, low addition on the side of the church with four windows, flat roof3 ring binder: N3 Page 13 N3 Black & White Minnehaha County Survey, Phase 1 August 1995 Photo RecordsMinnehaha County Survey Surveyor: M. D. Dennis August 14 1995 5062 PX Kodak Roll 13 Frame 5 Site MH-BT-03 Name Benton Lutheran Churc

    Study of DsJ decays to D+KS0 and D0K+ final states in pp collisions

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    A study of D+K0S and D0K+ final states is performed in a sample of 1.0 fb−1 of pp collision data collected at a centre-of-mass energy of s√=7 TeV with the LHCb detector. We confirm the existence of the D∗s1(2700)+ and D∗sJ(2860)+ excited states and measure their masses and widths to be m(D∗s1(2700)+) = 2709.2±1.9(stat)±4.5(syst) MeV/c2, Γ(D∗s1(2700)+) = 115.8±7.3(stat)±12.1(syst) MeV/c2, m(D∗sJ(2860)+) = 2866.1±1.0(stat)±6.3(syst) MeV/c2, Γ(D∗sJ(2860)+) = 69.9±3.2(stat)±6.6(syst) MeV/c2

    Benton Lutheran Church, Crooks SD Minnehaha County

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    negative 35mm church with a steeple on the front, arched stained glass windows on the side, raised basement with windows, steps on the back, gable roof3 ring binder: N3 Page 13 N3 Black & White Minnehaha County Survey, Phase 1 August 1995 Photo RecordsMinnehaha County Survey Surveyor: M. D. Dennis August 14 1995 5062 PX Kodak Roll 13 Frame 8 Site MH-BT-03 Name Benton Lutheran Churc

    Benton Lutheran Church, Crooks SD Minnehaha County

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    negative 35mm church with a steeple on the front, arched stained glass windows on the side, raised basement with windows, steps on the back, gable roof, long, low addition on the side of the church with four windows, flat roof3 ring binder: N3 Page 13 N3 Black & White Minnehaha County Survey, Phase 1 August 1995 Photo RecordsMinnehaha County Survey Surveyor: M. D. Dennis August 14 1995 5062 PX Kodak Roll 13 Frame 6 Site MH-BT-03 Name Benton Lutheran Churc

    Benton Lutheran Church, Crooks SD Minnehaha County

    No full text
    negative 35mm church with a steeple on the front, arched stained glass windows on the side, raised basement with windows, steps on the back, gable roof3 ring binder: N3 Page 13 N3 Black & White Minnehaha County Survey, Phase 1 August 1995 Photo RecordsMinnehaha County Survey Surveyor: M. D. Dennis August 14 1995 5062 PX Kodak Roll 13 Frame 9 Site MH-BT-03 Name Benton Lutheran Churc

    Benton Lutheran Church, Crooks SD Minnehaha County

    No full text
    negative 35mm church with a steeple on the front, arched stained glass windows on the side, raised basement with windows, steps on the back, gable roof3 ring binder: N3 Page 13 N3 Black & White Minnehaha County Survey, Phase 1 August 1995 Photo RecordsMinnehaha County Survey Surveyor: M. D. Dennis August 14 1995 5062 PX Kodak Roll 13 Frame 4 Site MH-BT-03 Name Benton Lutheran Churc
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