54 research outputs found
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Seismogenic faulting in the Meruoca granite, NE Brazil, consistent with a local weak fracture zone
Influences of Domestication and Island Evolution on Dental Growth in Sheep
Funder: Department of Zoology, University of CambridgeFunder: Leverhulme Trust; doi: http://dx.doi.org/10.13039/501100000275Abstract: Domestication and island evolution can lead to changes of life history along the slow-fast gradient. Shifts of life history patterns, in turn, are potentially related to alterations of patterns and timing of tooth eruption. Schultzâs rule predicts an earlier eruption of molars relative to premolars as fecundity increases during the domestication process. On the other hand, evolution on a predator-free, resource limited island might lead to a generally slow life history and delayed tooth eruption, as in the Plio-Pleistocene Balearic caprine Myotragus. In this study, we investigate tooth eruption and its relation to life history in a unique sheep population that is an example of both domestication and island evolution: the ancient and feral Soay sheep (Ovis aries) of the St. Kilda archipelago, Scotland. Tooth eruption timing and sequence is investigated in a comparative framework featuring new data on other domestic sheep (O. aries), including European mouflon (O. a. musimon), as well as wild sheep (O. vignei, O. cycloceros, O. arkal, O. orientalis, O. ammon). These data indicate that the order of eruption is similar in wild and domestic sheep, despite the fundamental life history changes that came about with domestication. However, in contrast to other domestic sheep breeds, Soay sheep erupt their teeth at an absolute older age and also tend to grow more slowly, which resembles the evolutionary trend in island-adapted Myotragus. Despite these similarities, Soay sheep do not share the slow life history pattern inferred for Myotragus, highlighting the distinctive nature of tooth eruption in Soay sheep
Ask a Scientist Website: Trends in Chemistry Questions in Turkey
The purpose of this study was to investigate questions submitted by users of a website that is popular with Turkish students learning about chemistry and thereby to inform teachers about trends in student interest. The website contains articles and information about chemistry and encourages visitors to "Ask a Scientist" questions about the subject. Over 1,500 enquiries, submitted over a 5-year period between 2006 and 2011, were classified according to field of interest in chemistry, type of information requested in the question, and motivation for asking the question. The most popular category was basics of chemistry (27.1 %), followed by nuclear chemistry and chemistry of the elements (19.1 %). We found that 37.3 % of the questions sought factual information and 20.1 % explanatory information. Our analysis of enquirers' motivation for asking their questions indicated that 55.6 % were asked for non-applicative, while 26.8 % were asked for applicative reasons. With respect to gender, males asked 54.44 % of the questions
Integrated evaluation of the geology, aerogammaspectrometry and aeromagnetometry of the Sul-Riograndense Shield, southernmost Brazil
ContribuiçÔes do campo crĂtico do lazer para a promoção da saĂșde Contributions from the critical leisure field to the health promotion
Nos estudos do lazer para a promoção da saĂșde, ainda predomina a lĂłgica da ocupação ativa do corpo no tempo de nĂŁo-trabalho (lazer ativo), revelando a influĂȘncia do pensamento funcionalista, o qual, ao reduzir os vĂnculos entre sociedade e processo saĂșde-doença, indiscutivelmente nĂŁo condiz com o propĂłsito de promover a saĂșde da população. Em face deste quadro, e partindo da premissa de que na educação fĂsica brasileira, desde o inĂcio dos anos oitenta, proliferam diferentes concepçÔes que discutem a superação do discurso do lazer funcionalista, mas que tais formulaçÔes ainda sĂŁo praticamente desconhecidas da SaĂșde Coletiva e SaĂșde PĂșblica brasileiras, a partir de revisĂŁo bibliogrĂĄfica sobre o desenvolvimento do campo do lazer no paĂs, buscando reflexĂ”es conjunta aos pressupostos da promoção da saĂșde, este trabalho tem como objetivo apresentar concepçÔes crĂticas e alternativas do lazer em sua relação com a saĂșde, fundamentando-se numa proposta polĂtico-pedagĂłgica denominada lazerania. Em linhas gerais, esta Ă© uma concepção de lazer emancipatĂłrio que, partindo da problematização do fenĂŽmeno esportivo, proporciona o sentir, pensar e agir da população, visando Ă construção de uma sociedade fundada na solidariedade e com a participação de todos.<br>The studies about leisure for health promotion still tend to choose the active body occupation in the free-time (leisure activities), revealing the influence of the functionalist way of thinking, which trying to reduce the links between society and health-disease process, undoubtedly do not keep with the purpose of population health promotion. Focusing on this idea, and keeping in mind the premise that in the Brazilian physical training there are different opinions since the earliest 80s which try to achieve the purpose to avoid the ideas of the functionalist way of thinking. However, those opinions are almost unknown both in the Brazilian public health system and the collective health system, once the bibliography revision about leisure activities development was made in the country, looking for ideas taken in common knowledge for health promotion presuppositions, this report has the aim to show critical and alternatives concepts of leisure in the way it is linked to healthy as a real social change, using a political-pedagogical proposal called lazerania. In general, this is an emancipatory concept of leisure, which comes from the sport phenomenon as a problem and provides the feeling, thinking and behavior of the population, trying to build a society based on solidarity and consumer participation
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