682 research outputs found

    siRNA screen identifies QPCT as a druggable target for Huntington's disease.

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    Huntington's disease (HD) is a currently incurable neurodegenerative condition caused by an abnormally expanded polyglutamine tract in huntingtin (HTT). We identified new modifiers of mutant HTT toxicity by performing a large-scale 'druggable genome' siRNA screen in human cultured cells, followed by hit validation in Drosophila. We focused on glutaminyl cyclase (QPCT), which had one of the strongest effects on mutant HTT-induced toxicity and aggregation in the cell-based siRNA screen and also rescued these phenotypes in Drosophila. We found that QPCT inhibition induced the levels of the molecular chaperone αB-crystallin and reduced the aggregation of diverse proteins. We generated new QPCT inhibitors using in silico methods followed by in vitro screening, which rescued the HD-related phenotypes in cell, Drosophila and zebrafish HD models. Our data reveal a new HD druggable target affecting mutant HTT aggregation and provide proof of principle for a discovery pipeline from druggable genome screen to drug development

    Precise measurements of the properties of the B-1(5721)(0,+) and B-2*(5747)(0,+) states and observation of B-+,B-0 pi(-,+) mass structures

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    Invariant mass distributions of B+π− and B0π+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1 of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1(5721)0,+ and B2(5747)0,+ states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B+π− and B0π+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ (5840)0,+ and BJ (5960)0,+, whose masses and widths are obtained under different hypotheses for their quantum numbers

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

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    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    First observation and amplitude analysis of the B- -> D+K-pi(-) decay

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    The B-→D+K-π- decay is observed in a data sample corresponding to 3.0 fb-1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. Its branching fraction is measured to be B(B-→D+K-π-)=(7.31±0.19±0.22±0.39)×10-5 where the uncertainties are statistical, systematic and from the branching fraction of the normalization channel B-→D+π-π-, respectively. An amplitude analysis of the resonant structure of the B-→D+K-π- decay is used to measure the contributions from quasi-two-body B-→D0∗(2400)0K-, B-→D2∗(2460)0K-, and B-→DJ∗(2760)0K- decays, as well as from nonresonant sources. The DJ∗(2760)0 resonance is determined to have spin 1

    A study of CP violation in B-+/- -> DK +/- and B-+/- -> D pi(+/-) decays with D -> (KSK +/-)-K-0 pi(-/+) final states

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    A first study of CP violation in the decay modes B±[KS0K±π]Dh±B^\pm\to [K^0_{\rm S} K^\pm \pi^\mp]_D h^\pm and B±[KS0Kπ±]Dh±B^\pm\to [K^0_{\rm S} K^\mp \pi^\pm]_D h^\pm, where hh labels a KK or π\pi meson and DD labels a D0D^0 or D0\overline{D}^0 meson, is performed. The analysis uses the LHCb data set collected in pppp collisions, corresponding to an integrated luminosity of 3 fb1^{-1}. The analysis is sensitive to the CP-violating CKM phase γ\gamma through seven observables: one charge asymmetry in each of the four modes and three ratios of the charge-integrated yields. The results are consistent with measurements of γ\gamma using other decay modes

    Study of the rare B-s(0) and B-0 decays into the pi(+) pi(-) mu(+) mu(-) final state

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    A search for the rare decays Bs0π+πμ+μB_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0π+πμ+μB^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb1^{-1} collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/c2c^2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0π+πμ+μB_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0π+πμ+μB^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions are measured to be B(Bs0π+πμ+μ)=(8.6±1.5(stat)±0.7(syst)±0.7(norm))×108\mathcal{B}(B_s^0 \to \pi^+\pi^-\mu^+\mu^-)=(8.6\pm 1.5\,({\rm stat}) \pm 0.7\,({\rm syst})\pm 0.7\,({\rm norm}))\times 10^{-8} and B(B0π+πμ+μ)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×108\mathcal{B}(B^0 \to \pi^+\pi^-\mu^+\mu^-)=(2.11\pm 0.51\,({\rm stat}) \pm 0.15\,({\rm syst})\pm 0.16\,({\rm norm}) )\times 10^{-8}, where the third uncertainty is due to the branching fraction of the decay B0J/ψ(μ+μ)K(890)0(K+π)B^0\to J/\psi(\to \mu^+\mu^-)K^*(890)^0(\to K^+\pi^-), used as a normalisation.A search for the rare decays Bs0→π+π−μ+μ− and B0→π+π−μ+μ− is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1 collected by the LHCb detector in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5–1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−μ+μ− and the first evidence of the decay B0→π+π−μ+μ− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−μ+μ−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−μ+μ−)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×10−8 , where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→μ+μ−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0→π+π−μ+μ− and B0→π+π−μ+μ− is performed in a data set corresponding to an integrated luminosity of 3.0 fb−1 collected by the LHCb detector in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5–1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0→π+π−μ+μ− and the first evidence of the decay B0→π+π−μ+μ− are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0→π+π−μ+μ−)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))×10−8 and B(B0→π+π−μ+μ−)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×10−8 , where the third uncertainty is due to the branching fraction of the decay B0→J/ψ(→μ+μ−)K⁎(892)0(→K+π−) , used as a normalisation.A search for the rare decays Bs0π+πμ+μB_s^0 \to \pi^+\pi^-\mu^+\mu^- and B0π+πμ+μB^0 \to \pi^+\pi^-\mu^+\mu^- is performed in a data set corresponding to an integrated luminosity of 3.0 fb1^{-1} collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/c2c^2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0π+πμ+μB_s^0 \to \pi^+\pi^-\mu^+\mu^- and the first evidence of the decay B0π+πμ+μB^0 \to \pi^+\pi^-\mu^+\mu^- are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0π+πμ+μ)=(8.6±1.5(stat)±0.7(syst)±0.7(norm))×108\mathcal{B}(B_s^0 \to \pi^+\pi^-\mu^+\mu^-)=(8.6\pm 1.5\,({\rm stat}) \pm 0.7\,({\rm syst})\pm 0.7\,({\rm norm}))\times 10^{-8} and B(B0π+πμ+μ)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))×108\mathcal{B}(B^0 \to \pi^+\pi^-\mu^+\mu^-)=(2.11\pm 0.51\,({\rm stat}) \pm 0.15\,({\rm syst})\pm 0.16\,({\rm norm}) )\times 10^{-8}, where the third uncertainty is due to the branching fraction of the decay B0J/ψ(μ+μ)K(890)0(K+π)B^0\to J/\psi(\to \mu^+\mu^-)K^*(890)^0(\to K^+\pi^-), used as a normalisation

    Observation of the B0 → ρ0ρ0 decay from an amplitude analysis of B0 → (π+π−)(π+π−) decays

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    Proton–proton collision data recorded in 2011 and 2012 by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb−1 , are analysed to search for the charmless B0→ρ0ρ0 decay. More than 600 B0→(π+π−)(π+π−) signal decays are selected and used to perform an amplitude analysis, under the assumption of no CP violation in the decay, from which the B0→ρ0ρ0 decay is observed for the first time with 7.1 standard deviations significance. The fraction of B0→ρ0ρ0 decays yielding a longitudinally polarised final state is measured to be fL=0.745−0.058+0.048(stat)±0.034(syst) . The B0→ρ0ρ0 branching fraction, using the B0→ϕK⁎(892)0 decay as reference, is also reported as B(B0→ρ0ρ0)=(0.94±0.17(stat)±0.09(syst)±0.06(BF))×10−6

    Measurement of the (eta c)(1S) production cross-section in proton-proton collisions via the decay (eta c)(1S) -> p(p)over-bar

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    The production of the ηc(1S)\eta_c (1S) state in proton-proton collisions is probed via its decay to the ppˉp \bar{p} final state with the LHCb detector, in the rapidity range 2.06.52.0 6.5 GeV/c. The cross-section for prompt production of ηc(1S)\eta_c (1S) mesons relative to the prompt J/ψJ/\psi cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.74 \pm 0.29 \pm 0.28 \pm 0.18 _{B} at a centre-of-mass energy s=7\sqrt{s} = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb1^{-1}, and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{B} at s=8\sqrt{s} = 8 TeV using 2.0 fb1^{-1}. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta_c (1S) and J/ψJ/\psi decays to the ppˉp \bar{p} final state. In addition, the inclusive branching fraction of bb-hadron decays into ηc(1S)\eta_c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.25±0.67B)×103B ( b \rightarrow \eta_c X ) = (4.88 \pm 0.64 \pm 0.25 \pm 0.67 _{B}) \times 10^{-3}, where the third uncertainty includes also the uncertainty on the J/ψJ/\psi inclusive branching fraction from bb-hadron decays. The difference between the J/ψJ/\psi and ηc(1S)\eta_c (1S) meson masses is determined to be 114.7±1.5±0.1114.7 \pm 1.5 \pm 0.1 MeV/c2^2.The production of the ηc(1S)\eta _c (1S) state in proton-proton collisions is probed via its decay to the ppp\overline{p} final state with the LHCb detector, in the rapidity range 2.06.5GeV/c2.0 6.5 \mathrm{{\,GeV/}{ c}} . The cross-section for prompt production of ηc(1S)\eta _c (1S) mesons relative to the prompt J/ψ{{ J}}/{\psi } cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma _{\eta _c (1S)}/\sigma _{{{{ J}}/{\psi }}} = 1.74\, \pm \,0.29\, \pm \, 0.28\, \pm \,0.18 _{{\mathcal{B}}} at a centre-of-mass energy s=7 TeV{\sqrt{s}} = 7 {~\mathrm{TeV}} using data corresponding to an integrated luminosity of 0.7 fb1^{-1} , and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma _{\eta _c (1S)}/\sigma _{{{{ J}}/{\psi }}} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{{\mathcal{B}}} at s=8 TeV{\sqrt{s}} = 8 {~\mathrm{TeV}} using 2.0 fb1^{-1} . The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta _c (1S) and J/ψ{{ J}}/{\psi } decays to the ppp\overline{p} final state. In addition, the inclusive branching fraction of b{b} -hadron decays into ηc(1S)\eta _c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.29±0.67B)×103{\mathcal{B}}( b {\rightarrow } \eta _c X ) = (4.88\, \pm \,0.64\, \pm \,0.29\, \pm \, 0.67 _{{\mathcal{B}}}) \times 10^{-3} , where the third uncertainty includes also the uncertainty on the J/ψ{{ J}}/{\psi } inclusive branching fraction from b{b} -hadron decays. The difference between the J/ψ{{ J}}/{\psi } and ηc(1S)\eta _c (1S) meson masses is determined to be 114.7±1.5±0.1MeV ⁣/c2114.7 \pm 1.5 \pm 0.1 {\mathrm {\,MeV\!/}c^2} .The production of the ηc(1S)\eta_c (1S) state in proton-proton collisions is probed via its decay to the ppˉp \bar{p} final state with the LHCb detector, in the rapidity range 2.06.52.0 6.5 GeV/c. The cross-section for prompt production of ηc(1S)\eta_c (1S) mesons relative to the prompt J/ψJ/\psi cross-section is measured, for the first time, to be σηc(1S)/σJ/ψ=1.74±0.29±0.28±0.18B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.74 \pm 0.29 \pm 0.28 \pm 0.18 _{B} at a centre-of-mass energy s=7\sqrt{s} = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb1^{-1}, and σηc(1S)/σJ/ψ=1.60±0.29±0.25±0.17B\sigma_{\eta_c (1S)}/\sigma_{J/\psi} = 1.60 \pm 0.29 \pm 0.25 \pm 0.17 _{B} at s=8\sqrt{s} = 8 TeV using 2.0 fb1^{-1}. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the ηc(1S)\eta_c (1S) and J/ψJ/\psi decays to the ppˉp \bar{p} final state. In addition, the inclusive branching fraction of bb-hadron decays into ηc(1S)\eta_c (1S) mesons is measured, for the first time, to be B(bηcX)=(4.88±0.64±0.29±0.67B)×103B ( b \rightarrow \eta_c X ) = (4.88 \pm 0.64 \pm 0.29 \pm 0.67 _{B}) \times 10^{-3}, where the third uncertainty includes also the uncertainty on the J/ψJ/\psi inclusive branching fraction from bb-hadron decays. The difference between the J/ψJ/\psi and ηc(1S)\eta_c (1S) meson masses is determined to be 114.7±1.5±0.1114.7 \pm 1.5 \pm 0.1 MeV/c2^2

    Angular analysis of the B-0 -> K*(0) e(+) e(-) decay in the low-q(2) region

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    An angular analysis of the B0K0e+eB^0 \rightarrow K^{*0} e^+ e^- decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 {\mbox{fb}^{-1}}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2q^2) interval between 0.002 and 1.120GeV2 ⁣/c4{\mathrm{\,Ge\kern -0.1em V^2\!/}c^4}. The angular observables FLF_{\mathrm{L}} and ATReA_{\mathrm{T}}^{\mathrm{Re}} which are related to the K0K^{*0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL=0.16±0.06±0.03F_{\mathrm{L}}= 0.16 \pm 0.06 \pm0.03 and ATRe=0.10±0.18±0.05A_{\mathrm{T}}^{\mathrm{Re}} = 0.10 \pm 0.18 \pm 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)A_{\mathrm{T}}^{(2)} and ATImA_{\mathrm{T}}^{\mathrm{Im}} which are sensitive to the photon polarisation in this q2q^2 range, are found to be AT(2)=0.23±0.23±0.05A_{\mathrm{T}}^{(2)} = -0.23 \pm 0.23 \pm 0.05 and ATIm=0.14±0.22±0.05A_{\mathrm{T}}^{\mathrm{Im}} =0.14 \pm 0.22 \pm 0.05. The results are consistent with Standard Model predictions.An angular analysis of the B0^{0} → K^{*}^{0} e+^{+} e^{−} decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 fb1^{−1}, collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2^{2}) interval between 0.002 and 1.120 GeV2^{2} /c4^{4}. The angular observables FL_{L} and ATRe_{T}^{Re} which are related to the K^{*}^{0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL_{L} = 0.16 ± 0.06 ± 0.03 and ATRe_{T}^{Re}  = 0.10 ± 0.18 ± 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)_{T}^{(2)} and ATIm_{T}^{Im} which are sensitive to the photon polarisation in this q2^{2} range, are found to be AT(2)_{T}^{(2)}  = − 0.23 ± 0.23 ± 0.05 and ATIm_{T}^{Im}  = 0.14 ± 0.22 ± 0.05. The results are consistent with Standard Model predictions.An angular analysis of the B0K0e+eB^0 \rightarrow K^{*0} e^+ e^- decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 {\mbox{fb}^{-1}}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared (q2q^2) interval between 0.002 and 1.120GeV2 ⁣/c4{\mathrm{\,Ge\kern -0.1em V^2\!/}c^4}. The angular observables FLF_{\mathrm{L}} and ATReA_{\mathrm{T}}^{\mathrm{Re}} which are related to the K0K^{*0} polarisation and to the lepton forward-backward asymmetry, are measured to be FL=0.16±0.06±0.03F_{\mathrm{L}}= 0.16 \pm 0.06 \pm0.03 and ATRe=0.10±0.18±0.05A_{\mathrm{T}}^{\mathrm{Re}} = 0.10 \pm 0.18 \pm 0.05, where the first uncertainty is statistical and the second systematic. The angular observables AT(2)A_{\mathrm{T}}^{(2)} and ATImA_{\mathrm{T}}^{\mathrm{Im}} which are sensitive to the photon polarisation in this q2q^2 range, are found to be AT(2)=0.23±0.23±0.05A_{\mathrm{T}}^{(2)} = -0.23 \pm 0.23 \pm 0.05 and ATIm=0.14±0.22±0.05A_{\mathrm{T}}^{\mathrm{Im}} =0.14 \pm 0.22 \pm 0.05. The results are consistent with Standard Model predictions

    Studies of beauty baryon decays to D0ph− and Λ+ch− final states

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