2,574 research outputs found

    Canonical interpretation of Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) in the Υ\Upsilon family

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    Inspired by the new resonance Y(10750)Y(10750), we calculate the masses and two-body OZI-allowed strong decays of the higher vector bottomonium sates within both screened and linear potential models. We discuss the possibilities of Υ(10860)\Upsilon(10860) and Y(10750)Y(10750) as mixed states via the SDS-D mixing. Our results suggest that Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) might be explained as mixed states between 5S5S- and 4D4D-wave vector bbˉb\bar{b} states. The Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) resonances may correspond to the mixed states dominated by the 4D4D- and 5S5S-wave components, respectively. The mass and the strong decay behaviors of the Υ(11020)\Upsilon(11020) resonance are consistent with the assignment of the Υ(6S)\Upsilon(6S) state in the potential models.Comment: 9 pages, 4 figures. More discussions are adde

    Cooperative three- and four- player quantum games

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    A cooperative multi-player quantum game played by 3 and 4 players has been studied. Quantum superposed operator is introduced in this work which solves the non-zero sum difficulty in previous treatment. The role of quantum entanglement of the initial state is discussed in details.Comment: 7 pages with 3 figures. To appear in Physics Letters

    Newton-Cartan Gravity and Torsion

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    We compare the gauging of the Bargmann algebra, for the case of arbitrary torsion, with the result that one obtains from a null-reduction of General Relativity. Whereas the two procedures lead to the same result for Newton-Cartan geometry with arbitrary torsion, the null-reduction of the Einstein equations necessarily leads to Newton-Cartan gravity with zero torsion. We show, for three space-time dimensions, how Newton-Cartan gravity with arbitrary torsion can be obtained by starting from a Schroedinger field theory with dynamical exponent z=2 for a complex compensating scalar and next coupling this field theory to a z=2 Schroedinger geometry with arbitrary torsion. The latter theory can be obtained from either a gauging of the Schroedinger algebra, for arbitrary torsion, or from a null-reduction of conformal gravity.Comment: 21 page

    B-vitamin consumption and the prevalence of diabetes and obesity among the US adults: population based ecological study

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    <p>Abstract</p> <p>Background</p> <p>The global increased prevalence of obesity and diabetes occurred after the worldwide spread of B-vitamins fortification, in which whether long-term exposure to high level of B vitamins plays a role is unknown. Our aim was to examine the relationships between B-vitamins consumption and the obesity and diabetes prevalence.</p> <p>Methods</p> <p>This population based ecological study was conducted to examine possible associations between the consumption of the B vitamins and macronutrients and the obesity and diabetes prevalence in the US population using the per capita consumption data from the US Economic Research Service and the prevalence data from the US Centers for Disease Control and Prevention.</p> <p>Results</p> <p>The prevalences of diabetes and adult obesity were highly correlated with per capita consumption of niacin, thiamin and riboflavin with a 26-and 10-year lag, respectively (<it>R</it><sup>2 </sup>= 0.952, 0.917 and 0.83 for diabetes, respectively, and <it>R</it><sup>2 </sup>= 0.964, 0.975 and 0.935 for obesity, respectively). The diabetes prevalence increased with the obesity prevalence with a 16-year lag (<it>R</it><sup>2 </sup>= 0.975). The relationships between the diabetes or obesity prevalence and per capita niacin consumption were similar both in different age groups and in male and female populations. The prevalence of adult obesity and diabetes was highly correlated with the grain contribution to niacin (<it>R</it><sup>2 </sup>= 0.925 and 0.901, respectively), with a 10-and 26-year lag, respectively. The prevalence of obesity in US adults during 1971-2004 increased in parallel with the increase in carbohydrate consumption with a 10-year lag. The per capita energy and protein consumptions positively correlated with the obesity prevalence with a one-year lag. Moreover, there was an 11-year lag relationship between per capita energy and protein consumption and the consumption of niacin, thiamin and riboflavin (<it>R</it><sup>2 </sup>= 0.932, 0.923 and 0.849 for energy, respectively, and <it>R</it><sup>2 </sup>= 0.922, 0.878 and 0.787 for protein, respectively).</p> <p>Conclusions</p> <p>Long-term exposure to high level of the B vitamins may be involved in the increased prevalence of obesity and diabetes in the US in the past 50 years. The possible roles of B-vitamins fortification and excess niacin consumption in the increased prevalence of obesity and diabetes were discussed.</p

    Thermal conduction of carbon nanotubes using molecular dynamics

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    The heat flux autocorrelation functions of carbon nanotubes (CNTs) with different radius and lengths is calculated using equilibrium molecular dynamics. The thermal conductance of CNTs is also calculated using the Green-Kubo relation from the linear response theory. By pointing out the ambiguity in the cross section definition of single wall CNTs, we use the thermal conductance instead of conductivity in calculations and discussions. We find that the thermal conductance of CNTs diverges with the CNT length. After the analysis of vibrational density of states, it can be concluded that more low frequency vibration modes exist in longer CNTs, and they effectively contribute to the divergence of thermal conductance.Comment: 15 pages, 6 figures, submitted to Physical Review

    Population phylogenomic analysis of mitochondrial DNA in wild boars and domestic pigs revealed multiple domestication events in East Asia

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    A fine-grained mitochondrial DNA phylogenomic analysis was conducted in domestic pigs and wild boars, revealing that pig domestication in East Asia occurred in the Mekong and the middle and downstream regions of the Yangtze river
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