7 research outputs found

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Secondary metabolites from Gentiana cruciata L. and their anti-inflammatory and analgesic activities

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    A previously unreported secoiridoid glycoside, cruciatoside (1) was isolated from the aerial parts of Gentiana cruciata L. along with ten known compounds eustomoside (2), eustomorusside (3), gentiopicroside (4), 6'-O-beta-D-glucopyranosyl gentiopicroside (5), loganic acid (6), isoorientin (7), isovitexin (8), isovitexin 2''-(E)-ferulate (9), mangiferin (10), and 2-methyl-inositol (11). The chemical structures of the isolates were elucidated based on extensive 1 D and 2 D NMR experiments as well as HRMS analysis. All isolates were evaluated for their in vitro anti-inflammatory and analgesic activities. Compounds 9, 4, and 7 (200 mu M) showed moderate anti-inflammatory activity by inhibiting nitrite production from LPS-induced RAW 264.7 macrophage cells, with the inhibition rates of 39.5%, 25.8% and 22.9% respectively without exhibiting substantial cytotoxicity. Besides, 1, 2, 4, and 7 exerted the highest decrease in IL-6 levels. Moreover, compound 4 showed in vitro analgesic activity by decreasing the PGE(2) level comparable to the reference drugs

    Secondary metabolites from Gentiana cruciata L. and their anti-inflammatory and analgesic activities

    No full text
    A previously unreported secoiridoid glycoside, cruciatoside (1) was isolated from the aerial parts of Gentiana cruciata L. along with ten known compounds eustomoside (2), eustomorusside (3), gentiopicroside (4), 6'-O-beta-D-glucopyranosyl gentiopicroside (5), loganic acid (6), isoorientin (7), isovitexin (8), isovitexin 2''-(E)-ferulate (9), mangiferin (10), and 2-methyl-inositol (11). The chemical structures of the isolates were elucidated based on extensive 1 D and 2 D NMR experiments as well as HRMS analysis. All isolates were evaluated for their in vitro anti-inflammatory and analgesic activities. Compounds 9, 4, and 7 (200 mu M) showed moderate anti-inflammatory activity by inhibiting nitrite production from LPS-induced RAW 264.7 macrophage cells, with the inhibition rates of 39.5%, 25.8% and 22.9% respectively without exhibiting substantial cytotoxicity. Besides, 1, 2, 4, and 7 exerted the highest decrease in IL-6 levels. Moreover, compound 4 showed in vitro analgesic activity by decreasing the PGE(2) level comparable to the reference drugs

    Secondary metabolites from <i>Gentiana cruciata</i> L. and their anti-inflammatory and analgesic activities

    No full text
    A previously unreported secoiridoid glycoside, cruciatoside (1) was isolated from the aerial parts of Gentiana cruciata L. along with ten known compounds eustomoside (2), eustomorusside (3), gentiopicroside (4), 6'-O-β-D-glucopyranosyl gentiopicroside (5), loganic acid (6), isoorientin (7), isovitexin (8), isovitexin 2''-(E)-ferulate (9), mangiferin (10), and 2-methyl-inositol (11). The chemical structures of the isolates were elucidated based on extensive 1 D and 2 D NMR experiments as well as HRMS analysis. All isolates were evaluated for their in vitro anti-inflammatory and analgesic activities. Compounds 9, 4, and 7 (200 µM) showed moderate anti-inflammatory activity by inhibiting nitrite production from LPS-induced RAW 264.7 macrophage cells, with the inhibition rates of 39.5%, 25.8% and 22.9% respectively without exhibiting substantial cytotoxicity. Besides, 1, 2, 4, and 7 exerted the highest decrease in IL-6 levels. Moreover, compound 4 showed in vitro analgesic activity by decreasing the PGE2 level comparable to the reference drugs.</p

    Measurements of ttˉt\bar{t} differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in pppp collisions at s=13\sqrt{s}=13\, TeV using the ATLAS detector

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    Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and ttˉt\bar{t} system kinematic observables using proton--proton collisions at a center-of-mass energy of s=13\sqrt{s} = 13 TeV. The data set corresponds to an integrated luminosity of 36.136.1 fb1^{-1}, recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Events with two large-radius jets in the final state, one with transverse momentum pT>500p_{\rm T} > 500 GeV and a second with pT>350p_{\rm T}>350 GeV, are used for the measurement. The top-quark candidates are separated from the multijet background using jet substructure information and association with a bb-tagged jet. The measured spectra are corrected for detector effects to a particle-level fiducial phase space and a parton-level limited phase space, and are compared to several Monte Carlo simulations by means of calculated χ2\chi^2 values. The cross-section for ttˉt\bar{t} production in the fiducial phase-space region is 292±7 (stat)±76(syst)292 \pm 7 \ \rm{(stat)} \pm 76 \rm{(syst)} fb, to be compared to the theoretical prediction of 384±36384 \pm 36 fb

    Measurements of ttˉt\bar{t} differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in pppp collisions at s=13\sqrt{s}=13\, TeV using the ATLAS detector

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    Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and ttˉt\bar{t} system kinematic observables using proton--proton collisions at a center-of-mass energy of s=13\sqrt{s} = 13 TeV. The data set corresponds to an integrated luminosity of 36.136.1 fb1^{-1}, recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Events with two large-radius jets in the final state, one with transverse momentum pT>500p_{\rm T} > 500 GeV and a second with pT>350p_{\rm T}>350 GeV, are used for the measurement. The top-quark candidates are separated from the multijet background using jet substructure information and association with a bb-tagged jet. The measured spectra are corrected for detector effects to a particle-level fiducial phase space and a parton-level limited phase space, and are compared to several Monte Carlo simulations by means of calculated χ2\chi^2 values. The cross-section for ttˉt\bar{t} production in the fiducial phase-space region is 292±7 (stat)±76(syst)292 \pm 7 \ \rm{(stat)} \pm 76 \rm{(syst)} fb, to be compared to the theoretical prediction of 384±36384 \pm 36 fb
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