1,270 research outputs found

    Ten more years of discovery: revisiting the quality of the sauropodomorph dinosaur fossil record

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    Spatiotemporal changes in fossil specimen completeness can bias our understanding of a group's evolutionary history. The quality of the sauropodomorph fossil record was assessed a decade ago, but the number of valid species has since increased by 60%, and 17% of the taxa from that study have since undergone taxonomic revision. Here, we assess how 10 years of additional research has changed our outlook on the group's fossil record. We quantified the completeness of all 307 sauropodomorph species currently considered valid using the skeletal completeness metric, which calculates the proportion of a complete skeleton preserved for each taxon. Taxonomic and stratigraphic age revisions, rather than new species, are the drivers of the most significant differences between the current results and those of the previous assessment. No statistical differences appeared when we use our new dataset to generate temporal completeness curves based solely on taxa known in 2009 or 1999. We now observe a severe drop in mean completeness values across the Jurassic–Cretaceous boundary that never recovers to pre‐Cretaceous levels. Explaining this pattern is difficult, as we find no convincing evidence that it is related to environmental preferences or body size changes. Instead, it might result from: (1) reduction of terrestrial fossil preservation space due to sea level rise; (2) ecological specificities and relatively high diagnosability of Cretaceous species; and/or (3) increased sampling of newly explored sites with many previously unknown taxa. Revisiting patterns in this manner allows us to test the longevity of conclusions made in previous quantitative studies

    Electroweak Physics at HERA: Introduction and Summary

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    A high luminosity upgrade of HERA will allow the measurement of standard model parameters and the neutral current couplings of quarks. These results will have to be consistent with other precision measurements or indicate traces of new physics. The analysis of WW production will complement future results of LEP 2 and the Tevatron. We summarize the main results and conclusions obtained by the working group on Electroweak Physics concerning the potential of future experimentation at HERA.Comment: 12 pages (Latex), 4 figures (Postscript), to appear in the Proceedings of the Workshop on Future Physics at HERA. The complete report by the working group on electroweak physics at HERA is available from http://www.desy.de/~heraws96/proceeding

    Search for the hero: an investigation into the sports heroes of British sports fans

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    This is an initial study into British sports fans’ heroes. A questionnaire was sent to 95 students (average age ÂŒ 19.75) to identify their sporting hero, the hero’s sport and nationality and the reasons for this choice. Football was the most common source of sports heroes, identified by 49% of participants with a sporting hero. The majority (60%, N ÂŒ 48) of heroes chosen by participants were British, with David Beckham the most popular choice. Differences were observed between the gender of participants, gender of hero chosen and the reasons for choosing the hero. The most common reason for selecting a hero was a personal trait rather than skill, while in the questionnaire a category of Local Affiliation was added to those suggested by previous work. It was concluded that to become a hero athletes should combine skill with devotion to family, charity work and a place in popular culture

    Anomalous Neutrino Reactions at HERA

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    We study the sensitivity of HERA to new physics using the helicity suppressed reaction eRp→ΜXe_R p \rightarrow \nu X , where the final neutrino can be a standard model one or a heavy neutrino. The approach is model independent and is based on an effective lagrangian parametrization. It is shown that HERA will put significant bounds on the scale of new physics, though, in general, these are more modest than previously thought. If deviations from the standard model are observed in the above processes, future colliders such as the SSC and LHC will be able to directly probe the physics responsible for these discrepancies}Comment: 11 Pages + 2 figures is TOPDRAWER (included at the end or available by mail). Report UCRHEP-T113 (requires the macropackage PHYZZX). A line in the TeX file requesting an input file has been removed, it caused problem

    The holy blood and the holy grail: Myths of scientific racism and the pursuit of excellence in sport

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    Despite the continuing publication of research that suggests there is no scientific basis to 'race' as a biological category, theories of racial difference continue to be invoked within sport to explain the perceived dominance of black athletes. In the case of John Entine's controversial 'Taboo: why black athletes dominate sports and why we are afraid to talk about it' or undergraduate textbooks that suggest 'racial differences' in physique may significantly affect athletic performance, scientific racism is normalised in sport. In this article, the relationship between scientific racism and sport will be examined. Qualitative research with current sport scientists is used to investigate the socio-ethical tensions within the subject field of sport science between professionalism, scientism and the demand from external interests to produce results that help people in sport win medals. It will be shown that these tensions, combined with the history of race as a category in sport science, combine to create the discourse of scientific knowledge that reflects, rather than challenges, folk genetics of black athletic physicality
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